National Library of Energy BETA

Sample records for aerosol optical depths

  1. Hyperspectral Aerosol Optical Depths from TCAP Flights

    SciTech Connect (OSTI)

    Shinozuka, Yohei; Johnson, Roy R.; Flynn, Connor J.; Russell, P. B.; Schmid, Beat; Redemann, Jens; Dunagan, Stephen; Kluzek, Celine D.; Hubbe, John M.; Segal-Rosenheimer, Michal; Livingston, J. M.; Eck, T.; Wagener, Richard; Gregory, L.; Chand, Duli; Berg, Larry K.; Rogers, Ray; Ferrare, R. A.; Hair, John; Hostetler, Chris A.; Burton, S. P.

    2013-11-13

    4STAR (Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research), the world’s first hyperspectral airborne tracking sunphotometer, acquired aerosol optical depths (AOD) at 1 Hz during all July 2012 flights of the Two Column Aerosol Project (TCAP). Root-mean square differences from AERONET ground-based observations were 0.01 at wavelengths between 500-1020 nm, 0.02 at 380 and 1640 nm and 0.03 at 440 nm in four clear-sky fly-over events, and similar in ground side-by-side comparisons. Changes in the above-aircraft AOD across 3-km-deep spirals were typically consistent with integrals of coincident in situ (on DOE Gulfstream 1 with 4STAR) and lidar (on NASA B200) extinction measurements within 0.01, 0.03, 0.01, 0.02, 0.02, 0.02 at 355, 450, 532, 550, 700, 1064 nm, respectively, despite atmospheric variations and combined measurement uncertainties. Finer vertical differentials of the 4STAR measurements matched the in situ ambient extinction profile within 14% for one homogeneous column. For the AOD observed between 350-1660 nm, excluding strong water vapor and oxygen absorption bands, estimated uncertainties were ~0.01 and dominated by (then) unpredictable throughput changes, up to +/-0.8%, of the fiber optic rotary joint. The favorable intercomparisons herald 4STAR’s spatially-resolved high-frequency hyperspectral products as a reliable tool for climate studies and satellite validation.

  2. Aerosol Optical Depth Value-Added Product Report

    SciTech Connect (OSTI)

    Koontz, A; Hodges, G; Barnard, J; Flynn, C; Michalsky, J

    2013-03-17

    This document describes the process applied to retrieve aerosol optical depth (AOD) from multifilter rotating shadowband radiometers (MFRSR) and normal incidence multifilter radiometers (NIMFR) operated at the ARM Climate Research Facility’s ground-based facilities.

  3. ARM: 10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    1998-03-01

    10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

  4. ARM: 10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

  5. Aerosol Optical Depth Prediction from Satellite Observations by Multiple Instance Regression

    E-Print Network [OSTI]

    Vucetic, Slobodan

    Aerosol Optical Depth Prediction from Satellite Observations by Multiple Instance Regression airborne particles that both reflect and absorb incoming solar radiation and whose effect on the Earth the satellite measure- ments, the common objective is prediction of Aerosol Opti- cal Depth (AOD). An important

  6. Quantifying Aerosol Direct Effects from Broadband Irradiance and Spectral Aerosol Optical Depth Observations

    SciTech Connect (OSTI)

    Creekmore, Torreon N.; Joseph, Everette; Long, Charles N.; Li, Siwei

    2014-05-16

    We outline a methodology using broadband and spectral irradiances to quantify aerosol direct effects on the surface diffuse shortwave (SW) irradiance. Best Estimate Flux data span a 13 year timeframe at the Department of Energy Atmospheric Radiation Measurement Program’s Southern Great Plains (SGP) site. Screened clear-sky irradiances and aerosol optical depth (AOD), for solar zenith angles ? 65°, are used to estimate clear-sky diffuse irradiances. We validate against detected clear-sky observations from SGP’s Basic Radiation System (BRS). BRS diffuse irradiances were in accordance with estimates, producing a root-mean-square error and mean bias errors of 4.0 W/m2 and -1.4 W/m2, respectively. Absolute differences show 99% of estimates within ±10 W/m2 (10%) of the mean BRS observations. Clear-sky diffuse estimates are used to derive quantitative estimates of aerosol radiative effects, represented as the aerosol diffuse irradiance (ADI). ADI is the contribution of diffuse SW to global SW, attributable to scattering of atmospheric transmission by natural plus anthropogenic aerosols. Estimated slope for the ADI as a function of AOD indicates an increase of ~22 W/m2 in diffuse SW for every 0.1 increase in AOD. Such significant increases in the diffuse fraction could possibly increase photosynthesis. Annual mean ADI is 28.2 W/m2, and heavy aerosol loading at SGP provides up to a maximum increase of 120 W/m2 in diffuse SW over background conditions. With regard to seasonal variation, the mean diffuse forcings are 17.2, 33.3, 39.0, and 23.6 W/m2 for winter, spring, summer, and fall, respectively.

  7. Determination of aerosol optical depth using a Micro Total Ozone Spectrometer II (MICROTOPS II) sunphotometer

    E-Print Network [OSTI]

    of Energy, the Office of Educational Program, the National Science Foundation and the Louis Stokes Alliances solar radiation. These effects are quantified by the aerosol optical depth (AOD), which is the exponential decrease in solar radiation, due to the presence of aerosols. We performed the retrievals of AOD

  8. Airborne Sun photometer measurements of aerosol optical depth and columnar water vapor during the Puerto Rico Dust Experiment and

    E-Print Network [OSTI]

    Christopher, Sundar A.

    Airborne Sun photometer measurements of aerosol optical depth and columnar water vapor during to within 0.004­0.030 with coincident data obtained with an AERONET Sun/ sky radiometer located on Cabras Dynamics: Remote sensing; KEYWORDS: PRIDE, airborne Sun photometer, aerosol optical depth, columnar water

  9. Relative humidity and its effect on aerosol optical depth in the vicinity of convective clouds

    E-Print Network [OSTI]

    Altaratz, O

    The hygroscopic growth of aerosols is controlled by the relative humidity (RH) and changes the aerosols' physical and hence optical properties. Observational studies of aerosol–cloud interactions evaluate the aerosol ...

  10. Mars aerosol studies with the MGS TES emission phase function observations: Optical depths, particle

    E-Print Network [OSTI]

    Whitney, Barbara A.

    aerosol properties to date. TES solar band and infrared (IR) spectral EPF sequences are analyzed to obtain and scattering of radiation; 6225 Planetology: Solar System Objects: Mars; KEYWORDS: Martian atmosphere, aerosols, radiative forcing from atmo- spheric dust solar absorption and thermal emission was recognized as a primary

  11. Aerosol Optical Depth Retrieval by Neural Networks Ensemble with Adaptive Cost Function

    E-Print Network [OSTI]

    Obradovic, Zoran

    and warming the atmosphere. Therefore, the accurate prediction of aerosols composition and their concentration (AERONET) is global remote sensing network of about 540 ground-based radiometers that retrieve AOD several as ground truth when validating retrieval quality of various satellite- based AOD retrieval algorithms [4

  12. Niamey Aerosol Optical Depths

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Flynn, Connor

    2008-10-01

    MFRSR irradiance data collected during the ACRF AMF deployment in Niamey, Niger have been used to derive AOD for five wavelength channels of the MFRSR. These data have been corrected to adjust for filter drift over the course of the campaign and contamination due to forward scattering as a result of large dust particles in the atmosphere around Niamey.

  13. How do A-train Sensors Intercompare in the Retrieval of Above-Cloud Aerosol Optical Depth? A Case Study-based Assessment

    SciTech Connect (OSTI)

    Jethva, H. T.; Torres, O.; Waquet, F.; Chand, Duli; Hu, Yong X.

    2014-01-16

    We inter-compare the above-cloud aerosol optical depth (ACAOD) of biomass burning plumes retrieved from different A-train sensors, i.e., MODIS, CALIOP, POLDER, and OMI. These sensors have shown independent capabilities to detect and retrieve aerosol loading above marine boundary layer clouds--a kind of situation often found over the Southeast Atlantic Ocean during dry burning season. A systematic one-to-one comparison reveals that, in general, all passive sensors and CALIOP-based research methods derive comparable ACAOD with differences mostly within 0.2 over homogeneous cloud fields. The 532-nm ACAOD retrieved by CALIOP operational algorithm is largely underestimated; however, it’s 1064-nm AOD when converted to 500 nm shows closer agreement to the passive sensors. Given the different types of sensor measurements processed with different algorithms, the close agreement between them is encouraging. Due to lack of adequate direct measurements above cloud, the validation of satellite-based ACAOD retrievals remains an open challenge. The inter-satellite comparison, however, can be useful for the relative evaluation and consistency check.

  14. Measurements of aerosol vertical profiles and optical properties during INDOEX

    E-Print Network [OSTI]

    , and the Kaashidhoo Climate Observatory (KCO) in the Maldives. Sun photometers were used to provide aerosol optical depths (AOD) needed to calibrate the MPL. This study focuses on the height distribution and optical trajectories, radiosonde profiles of temperature and humidity, and aerosol concentration and optical

  15. ARM - Measurement - Aerosol optical depth

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments?govInstrumentsnoaacrnBarrow, Alaska Outreach Home Room NewsgovMeasurementsAdvectiveeffective

  16. ARM: 10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    1998-03-01

    10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  17. ARM: 1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    2004-10-01

    1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  18. ARM: 10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  19. ARM: 1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  20. The spatial and temporal variability and distribution of aerosol optical depths throughout California and within its air districts and air basins

    E-Print Network [OSTI]

    Frank, Thomas D.

    , their causes, and their effects. The state of California has designated temporary air district and air basin in children (Gauderman et al., 2004), and development of asthma (Etzel, 2003). Aerosols also play an important

  1. ARM: 10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    2010-12-15

    10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  2. ARM: 10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  3. Determining Nighttime Atmospheric Optical Depth Using Mars Exploration Rover Images 

    E-Print Network [OSTI]

    Bean, Keri Marie

    2013-07-22

    was compared to the expected flux to give nighttime optical depth values. The observed nighttime optical depth was consistently similar to the daytime optical depth values on both an individual image and sol-averaged basis. Recommendations are made going...

  4. Global longterm passive microwave satellitebased retrievals of vegetation optical depth

    E-Print Network [OSTI]

    Evans, Jason

    Global longterm passive microwave satellitebased retrievals of vegetation optical depth Yi Y. Liu,1 optical depth (VOD) retrievals from three satellitebased passive microwave instruments were merged longterm passive microwave satellitebased retrievals of vegetation optical depth, Geophys. Res. Lett., 38

  5. Africa Aerosol Optical Depth Obtained From MISR

    E-Print Network [OSTI]

    Frank, Thomas D.

    Faso Cameroon Equatorial Guinea Gambia, The Ghana Guinea Guinea-Bissau Ivory Coast Liberia Mali Cameroon Equatorial Guinea Gambia, The Ghana Guinea Guinea-Bissau Ivory Coast Liberia Mali Mauritania

  6. ARM - PI Product - Niamey Aerosol Optical Depths

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments?govInstrumentsnoaacrnBarrow, Alaska OutreachCalendar NSAProductsMerged and corrected 915

  7. Aerosol control on depth of warm rain in convective clouds Mahen Konwar,1

    E-Print Network [OSTI]

    Daniel, Rosenfeld

    Aerosol control on depth of warm rain in convective clouds Mahen Konwar,1 R. S. Maheskumar,1 J. R effective radius (re) increased with distance above cloud base (D). Warm rain became detectable, i.e., rain water content >0.01 g/Kg, at the tops of growing convective clouds when re exceeded 12 mm. The re

  8. Characterizing Aerosol Distributions and Optical Properties Using the NASA Langley High Spectral Resolution Lidar

    SciTech Connect (OSTI)

    Hostetler, Chris; Ferrare, Richard

    2013-02-14

    The objective of this project was to provide vertically and horizontally resolved data on aerosol optical properties to assess and ultimately improve how models represent these aerosol properties and their impacts on atmospheric radiation. The approach was to deploy the NASA Langley Airborne High Spectral Resolution Lidar (HSRL) and other synergistic remote sensors on DOE Atmospheric Science Research (ASR) sponsored airborne field campaigns and synergistic field campaigns sponsored by other agencies to remotely measure aerosol backscattering, extinction, and optical thickness profiles. Synergistic sensors included a nadir-viewing digital camera for context imagery, and, later in the project, the NASA Goddard Institute for Space Studies (GISS) Research Scanning Polarimeter (RSP). The information from the remote sensing instruments was used to map the horizontal and vertical distribution of aerosol properties and type. The retrieved lidar parameters include profiles of aerosol extinction, backscatter, depolarization, and optical depth. Products produced in subsequent analyses included aerosol mixed layer height, aerosol type, and the partition of aerosol optical depth by type. The lidar products provided vertical context for in situ and remote sensing measurements from other airborne and ground-based platforms employed in the field campaigns and was used to assess the predictions of transport models. Also, the measurements provide a data base for future evaluation of techniques to combine active (lidar) and passive (polarimeter) measurements in advanced retrieval schemes to remotely characterize aerosol microphysical properties. The project was initiated as a 3-year project starting 1 January 2005. It was later awarded continuation funding for another 3 years (i.e., through 31 December 2010) followed by a 1-year no-cost extension (through 31 December 2011). This project supported logistical and flight costs of the NASA sensors on a dedicated aircraft, the subsequent analysis and archival of the data, and the presentation of results in conferences, workshops, and publications. DOE ASR field campaigns supported under this project included - MAX-Mex /MILAGRO (2006) - TexAQS 2006/GoMACCS (2006) - CHAPS (2007) - RACORO (2009) - CARE/CalNex (2010) In addition, data acquired on HSRL airborne field campaigns sponsored by other agencies were used extensively to fulfill the science objectives of this project and the data acquired have been made available to other DOE ASR investigators upon request.

  9. Retrievals of cloud optical depth and effective radius from Thin-Cloud Rotating Shadowband Radiometer measurements

    E-Print Network [OSTI]

    Retrievals of cloud optical depth and effective radius from Thin-Cloud Rotating Shadowband December 2011. [1] A Thin-Cloud Rotating Shadowband Radiometer (TCRSR) was developed and deployed) through an optically thin cloud (optical depth

  10. Aerosol Optical Depths In South/South East Asia

    E-Print Network [OSTI]

    Frank, Thomas D.

    Delhi Gujarat Himachal Pradesh Jammu and Kashmir Kerala Madhya Pradesh Manipur Meghalaya Karnataka Jammu and Kashmir Kerala Madhya Pradesh Manipur Meghalaya Karnataka Nagaland Orissa Punjab Rajasthan Delhi Gujarat Himachal Pradesh Jammu and Kashmir Kerala Madhya Pradesh Manipur Meghalaya Karnataka

  11. Climatology of aerosol optical depth in northcentral Oklahoma: 19922008

    E-Print Network [OSTI]

    dimming; that is, the decrease in solar radiation reaching Earth's surface. Additionally, the wavelength Radiation Measurement Program central facility near Lamont, Oklahoma, since the fall of 1992. Most of the data presented are from the multifilter rotating shadowband radiometer, a narrowband

  12. Trends in aerosol optical properties over the Bohai Rim in Northeast China from 2004 to 2010

    E-Print Network [OSTI]

    Zeng, Ning

    Trends in aerosol optical properties over the Bohai Rim in Northeast China from 2004 to 2010 al., 2004). However, the spatial and temporal contributions of aerosol optical properties and aerosol of this growth is driven by new industry that consumes substantially more coal and fossil fuel in the region

  13. Cloud-Driven Changes in Aerosol Optical Properties - Final Technical Report

    SciTech Connect (OSTI)

    Ogren, John A.; Sheridan, Patrick S.; Andrews, Elisabeth

    2007-09-30

    The optical properties of aerosol particles are the controlling factors in determining direct aerosol radiative forcing. These optical properties depend on the chemical composition and size distribution of the aerosol particles, which can change due to various processes during the particles’ lifetime in the atmosphere. Over the course of this project we have studied how cloud processing of atmospheric aerosol changes the aerosol optical properties. A counterflow virtual impactor was used to separate cloud drops from interstitial aerosol and parallel aerosol systems were used to measure the optical properties of the interstitial and cloud-scavenged aerosol. Specifically, aerosol light scattering, back-scattering and absorption were measured and used to derive radiatively significant parameters such as aerosol single scattering albedo and backscatter fraction for cloud-scavenged and interstitial aerosol. This data allows us to demonstrate that the radiative properties of cloud-processed aerosol can be quite different than pre-cloud aerosol. These differences can be used to improve the parameterization of aerosol forcing in climate models.

  14. Optical Properties of Mixed Black Carbon, Inorganic and Secondary Organic Aerosols

    SciTech Connect (OSTI)

    Paulson, S E

    2012-05-30

    Summarizes the achievements of the project, which are divided into four areas: 1) Optical properties of secondary organic aerosols; 2) Development and of a polar nephelometer to measure aerosol optical properties and theoretical approaches to several optical analysis problems, 3) Studies on the accuracy of measurements of absorbing carbon by several methods, and 4) Environmental impacts of biodiesel.

  15. Radiative Effects of Dust Aerosols, Natural Cirrus Clouds and Contrails: Broadband Optical Properties and Sensitivity Studies 

    E-Print Network [OSTI]

    Yi, Bingqi

    2013-07-09

    This dissertation aims to study the broadband optical properties and radiative effects of dust aerosols and ice clouds. It covers three main topics: the uncertainty of dust optical properties and radiative effects from the dust particle shape...

  16. Shortwave aerosol radiative forcing over cloud-free oceans from Terra: 1. Angular models for aerosols

    E-Print Network [OSTI]

    Christopher, Sundar A.

    Sensor Microwave Imager (SSM/I) data to obtain near surface wind speed. The new aerosol ADMs are built to obtain aerosol properties within a Clouds and Earth Radiant Energy System (CERES) footprint and Special as functions of near-surface ocean wind speed and MODIS aerosol optical depth at 0.55 mm (t0.55). Among the new

  17. Aerosol optical hygroscopicity measurements during the 2010 CARES campaign

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Atkinson, D. B.; Radney, J. G.; Lum, J.; Kolesar, K. R.; Cziczo, D. J.; Pekour, M. S.; Zhang, Q.; Setyan, A.; Zelenyuk, A.; Cappa, C. D.

    2015-04-17

    Measurements of the effect of water uptake on particulate light extinction or scattering made at two locations during the 2010 Carbonaceous Aerosols and Radiative Effects Study (CARES) study around Sacramento, CA are reported. The observed influence of water uptake, characterized through the dimensionless optical hygroscopicity parameter ?, is compared with calculations constrained by observed particle size distributions and size-dependent particle composition. A closure assessment has been carried out that allowed for determination of the average hygroscopic growth factors (GFs) at 85% relative humidity and the dimensionless hygroscopicity parameter ? for oxygenated organic aerosol (OA) and for supermicron particles (defined heremore »as particles with aerodynamic diameters between 1 and 2.5 microns), yielding ? = 0.1–0.15 and 0.9–1.0, respectively. The derived range of oxygenated OA ? values are in line with previous observations. The relatively large values for supermicron particles is consistent with substantial contributions of sea-salt-containing particles in this size range. Analysis of time-dependent variations in the supermicron particle hygroscopicity suggest that atmospheric processing, specifically chloride displacement by nitrate and the accumulation of secondary organics on supermicron particles, can lead to substantial depression of the observed GF.« less

  18. AERONET: The Aerosol Robotic Network

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    AERONET collaboration provides globally distributed observations of spectral aerosol optical Depth (AOD), inversion products, and precipitable water in diverse aerosol regimes. Aerosol optical depth data are computed for three data quality levels: Level 1.0 (unscreened), Level 1.5 (cloud-screened), and Level 2.0 (cloud screened and quality-assured). Inversions, precipitable water, and other AOD-dependent products are derived from these levels and may implement additional quality checks.[Copied from http://aeronet.gsfc.nasa.gov/new_web/system_descriptions.html

  19. Direct Aerosol Forcing Uncertainty

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Mccomiskey, Allison

    Understanding sources of uncertainty in aerosol direct radiative forcing (DRF), the difference in a given radiative flux component with and without aerosol, is essential to quantifying changes in Earth's radiation budget. We examine the uncertainty in DRF due to measurement uncertainty in the quantities on which it depends: aerosol optical depth, single scattering albedo, asymmetry parameter, solar geometry, and surface albedo. Direct radiative forcing at the top of the atmosphere and at the surface as well as sensitivities, the changes in DRF in response to unit changes in individual aerosol or surface properties, are calculated at three locations representing distinct aerosol types and radiative environments. The uncertainty in DRF associated with a given property is computed as the product of the sensitivity and typical measurement uncertainty in the respective aerosol or surface property. Sensitivity and uncertainty values permit estimation of total uncertainty in calculated DRF and identification of properties that most limit accuracy in estimating forcing. Total uncertainties in modeled local diurnally averaged forcing range from 0.2 to 1.3 W m-2 (42 to 20%) depending on location (from tropical to polar sites), solar zenith angle, surface reflectance, aerosol type, and aerosol optical depth. The largest contributor to total uncertainty in DRF is usually single scattering albedo; however decreasing measurement uncertainties for any property would increase accuracy in DRF. Comparison of two radiative transfer models suggests the contribution of modeling error is small compared to the total uncertainty although comparable to uncertainty arising from some individual properties.

  20. Direct Aerosol Forcing Uncertainty

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Mccomiskey, Allison

    2008-01-15

    Understanding sources of uncertainty in aerosol direct radiative forcing (DRF), the difference in a given radiative flux component with and without aerosol, is essential to quantifying changes in Earth's radiation budget. We examine the uncertainty in DRF due to measurement uncertainty in the quantities on which it depends: aerosol optical depth, single scattering albedo, asymmetry parameter, solar geometry, and surface albedo. Direct radiative forcing at the top of the atmosphere and at the surface as well as sensitivities, the changes in DRF in response to unit changes in individual aerosol or surface properties, are calculated at three locations representing distinct aerosol types and radiative environments. The uncertainty in DRF associated with a given property is computed as the product of the sensitivity and typical measurement uncertainty in the respective aerosol or surface property. Sensitivity and uncertainty values permit estimation of total uncertainty in calculated DRF and identification of properties that most limit accuracy in estimating forcing. Total uncertainties in modeled local diurnally averaged forcing range from 0.2 to 1.3 W m-2 (42 to 20%) depending on location (from tropical to polar sites), solar zenith angle, surface reflectance, aerosol type, and aerosol optical depth. The largest contributor to total uncertainty in DRF is usually single scattering albedo; however decreasing measurement uncertainties for any property would increase accuracy in DRF. Comparison of two radiative transfer models suggests the contribution of modeling error is small compared to the total uncertainty although comparable to uncertainty arising from some individual properties.

  1. Aerosol optical hygroscopicity measurements during the 2010 CARES Campaign

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Atkinson, D. B.; Radney, J. G.; Lum, J.; Kolesar, K. R.; Cziczo, D. J.; Pekour, M. S.; Zhang, Q.; Setyan, A.; Zelenyuk, A.; Cappa, C. D.

    2014-12-10

    Measurements of the effect of water uptake on particulate light extinction or scattering made at two locations during the 2010 CARES study around Sacramento, CA are reported. The observed influence of water uptake, characterized through the dimensionless optical hygroscopicity parameter ?, is compared with calculations constrained by observed particle size distributions and size-dependent particle composition. A closure assessment has been carried out that allowed for determination of the average hygroscopic growth factors (GF) at 85% relative humidity and the dimensionless hygroscopicity parameter ? for oxygenated organic aerosol (OA) and for supermicron particles, yielding ? = 0.1–0.15 and 0.9–1.0, respectively. Themore »derived range of oxygenated OA ? values are in line with previous observations. The relatively large values for supermicron particles is consistent with substantial contributions of sea salt-containing particles in this size range. Analysis of time-dependent variations in the supermicron particle hygroscopicity suggest that atmospheric processing, specifically chloride displacement by nitrate and the accumulation of secondary organics on supermicron particles, can lead to substantial depression of the observed GF.« less

  2. Aerosol optical hygroscopicity measurements during the 2010 CARES Campaign

    SciTech Connect (OSTI)

    Atkinson, D. B.; Radney, J. G.; Lum, J.; Kolesar, K. R.; Cziczo, Daniel J.; Pekour, Mikhail S.; Zhang, Qi; Setyan, Ari; Zelenyuk, Alla; Cappa, Christopher

    2015-01-01

    Measurements of the effect of water uptake on particulate light extinction or scattering made at two locations during the 2010 CARES study around Sacramento, CA are reported. The observed influence of water uptake, characterized through the dimensionless optical hygroscopicity parameter ?, is compared with calculations constrained by observed particle size distributions and size-dependent particle composition. A closure assessment has been carried out that allowed for determination of the average hygroscopic growth factors (GF) at 85% relative humidity and the dimensionless hygroscopicity parameter ? for oxygenated organic aerosol (OA) and for supermicron particles, yielding ? = 0.1–0.15 and 0.9–1.0, respectively. The derived range of oxygenated OA ? values are in line with previous observations. The relatively large values for supermicron particles is consistent with substantial contributions of sea salt-containing particles in this size range. Analysis of time-dependent variations in the supermicron particle hygroscopicity suggest that atmospheric processing, specifically chloride displacement by nitrate and the accumulation of secondary organics on supermicron particles, can lead to substantial depression of the observed GF.

  3. Aerosol optical hygroscopicity measurements during the 2010 CARES campaign

    E-Print Network [OSTI]

    Atkinson, D. B.

    Measurements of the effect of water uptake on particulate light extinction or scattering made at two locations during the 2010 Carbonaceous Aerosols and Radiative Effects Study (CARES) study around Sacramento, CA are ...

  4. LINKING Ly? AND LOW-IONIZATION TRANSITIONS AT LOW OPTICAL DEPTH

    SciTech Connect (OSTI)

    Jaskot, A. E.; Oey, M. S.

    2014-08-20

    We suggest that low optical depth in the Lyman continuum (LyC) may relate the Ly? emission, C II and Si II absorption, and C II* and Si II* emission seen in high-redshift galaxies. We base this analysis on Hubble Space Telescope Cosmic Origins Spectrograph spectra of four Green Pea (GP) galaxies, which may be analogs of z > 2 Ly? emitters (LAEs). In the two GPs with the strongest Ly? emission, the Ly? line profiles show reduced signs of resonant scattering. Instead, the Ly? profiles resemble the H? line profiles of evolved star ejecta, suggesting that the Ly? emission originates from a low column density and similar outflow geometry. The weak C II absorption and presence of non-resonant C II* emission in these GPs support this interpretation and imply a low LyC optical depth along the line of sight. In two additional GPs, weak Ly? emission and strong C II absorption suggest a higher optical depth. These two GPs differ in their Ly? profile shapes and C II* emission strengths, however, indicating different inclinations of the outflows to our line of sight. With these four GPs as examples, we explain the observed trends linking Ly?, C II, and C II* in stacked LAE spectra, in the context of optical depth and geometric effects. Specifically, in some galaxies with strong Ly? emission, a low LyC optical depth may allow Ly? to escape with reduced scattering. Furthermore, C II absorption, C II* emission, and Ly? profile shape can reveal the optical depth, constrain the orientation of neutral outflows in LAEs, and identify candidate LyC emitters.

  5. DISSERTATION THE OPTICAL, CHEMICAL, AND PHYSICAL PROPERTIES OF AEROSOLS AND

    E-Print Network [OSTI]

    Pierce, Jeffrey

    AND GASES EMITTED BY THE LABORATORY COMBUSTION OF WILDLAND FUELS Biomass burning is a major source of trace Laboratory at Missoula Experiment. Emission factors are presented as a function of modified combustion efficiency (MCE), a measure of the fire combustion conditions. The emissions of many trace gas and aerosol

  6. Variability of Aerosol Optical Properties from Long-term

    E-Print Network [OSTI]

    Delene, David J.

    aerosols and overestimates absorption due to suspended particles by about 20-30%. Green L E D Opal Glas s O Photometer · Principle of operation is to measure the change in light transmission through a filter on which light extinction and light scattering. · Instrument exhibits a significant response to nonabsorbing

  7. EVALUATING TREATMENTS OF AEROSOL OPTICAL PROPERTIES AND THEIR EFFECT ON RADIATIVE FORCING USING MILAGRO MEASUREMENTS

    E-Print Network [OSTI]

    at the American Geophysical Union Fall Meeting San Francisco, CA December 10-14, 2007 Environmental Sciences-chemistry-aerosol model, WRF-chem, to evaluate the predicted optical properties and downwind of Mexico City using both-averaging", "shell-core" and other approaches that employ Mie theory. The impact of the various approaches

  8. Smoke over haze: Comparative analysis of satellite, surface radiometer, and airborne in situ measurements of aerosol optical

    E-Print Network [OSTI]

    Zeng, Ning

    measurements of aerosol optical properties and radiative forcing over the eastern United States Brian Vant column closure between narrow and broadband measurements and calculations. Citation: Vant-Hull, B., Z. Li

  9. Lidar Measurements of the Vertical Distribution of Aerosol Optical and Physical Properties over Central Asia

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chen, Boris B.; Sverdlik, Leonid G.; Imashev, Sanjar A.; Solomon, Paul A.; Lantz, Jeffrey; Schauer, James J.; Shafer, Martin M.; Artamonova, Maria S.; Carmichael, Gregory R.

    2013-01-01

    The vertical structure of aerosol optical and physical properties was measured by Lidar in Eastern Kyrgyzstan, Central Asia, from June 2008 to May 2009. Lidar measurements were supplemented with surface-based measurements of PM 2.5 and PM 10 mass and chemical composition in both size fractions. Dust transported into the region is common, being detected 33% of the time. The maximum frequency occurred in the spring of 2009. Dust transported to Central Asia comes from regional sources, for example, Taklimakan desert and Aral Sea basin, and from long-range transport, for example, deserts of Arabia, Northeast Africa, Iran, and Pakistan. Regionalmore »sources are characterized by pollution transport with maximum values of coarse particles within the planetary boundary layer, aerosol optical thickness, extinction coefficient, integral coefficient of aerosol backscatter, and minimum values of the Ångström exponent. Pollution associated with air masses transported over long distances has different characteristics during autumn, winter, and spring. During winter, dust emissions were low resulting in high values of the Ångström exponent (about 0.51) and the fine particle mass fraction (64%). Dust storms were more frequent during spring with an increase in coarse dust particles in comparison to winter. The aerosol vertical profiles can be used to lower uncertainty in estimating radiative forcing. « less

  10. What controls the recent changes in African mineral dust aerosol across the Atlantic?

    E-Print Network [OSTI]

    Ridley, David Andrew

    Dust from Africa strongly perturbs the radiative balance over the Atlantic, with emissions that are highly variable from year to year. We show that the aerosol optical depth (AOD) of dust over the mid-Atlantic observed by ...

  11. DOE/SC-ARM/TR-129 Aerosol Optical Depth Value-Added Product

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent Bonding Low-Cost2 DOE HQSiteo n n e v i2 ARM Climate16233752502489

  12. The spatial and temporal variability of aerosol optical depths in the Mojave Desert of southern California

    E-Print Network [OSTI]

    Frank, Thomas D.

    California Thomas D. Frank a,, Larry Di Girolamo b,1 , Shannon Geegan a a Department of Geography, University of Illinois, 220 Davenport Hall, 607 S. Mathews Ave, Urbana, IL 61801, USA b Dept. of Atmospheric Sciences

  13. Aerosol Optical Depth Prediction from Satellite Observations by Multiple Instance Regression

    E-Print Network [OSTI]

    Obradovic, Zoran

    streams from multiple instruments. These instruments provide an unprecedented opportunity for long-term airborne particles that both reflect and absorb incoming solar radiation and whose effect on the Earth particles that reflect and absorb incoming solar radiation, on the global scale. The existing algorithms

  14. PREDICTING GROUND-BASED AEROSOL OPTICAL DEPTH WITH SATELLITE IMAGES VIA GAUSSIAN PROCESSES

    E-Print Network [OSTI]

    Obradovic, Zoran

    - formation is automatically determined. Experiments show that the spatio-temporal information contributes in the Earth's atmosphere, and have significant effects on human health (Baron, 2006) and climate changes incoming solar radiation. One of the biggest challenges of current climate research is to characterize

  15. Analysis of Langley optical depth data, with aerosol and gas retrievals,

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O D S TAPropaneandAn OverviewCoalAnalysisHeat Ratefor the

  16. DOE/SC-ARM/TR-133 Aerosol Optical Depth Value-Added

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home Room NewsInformation Current HAB Packet HanfordDOE ProjectREMOTE-HANDLED TRU764 The6552-013 ARM48923

  17. BIOMASS BURNING IN THE AMAZON: LINKS BETWEEN BURNING, SCIAMACHY TRACE GASES, AND AEROSOL AND SURFACE PROPERTIES FROM THE ORAC-AATSR RETRIEVAL

    E-Print Network [OSTI]

    Oxford, University of

    BIOMASS BURNING IN THE AMAZON: LINKS BETWEEN BURNING, SCIAMACHY TRACE GASES, AND AEROSOL@atm.ox.ac.uk AEROSOL AND GAS PROPERTIESSEASONALITY OF BURNING Biomass burning in the Amazon shows strong seasonal in aerosol optical depth (AOD) and effective radius, linked to biomass burning through detected fires. Use

  18. Absolute distance perception during in-depth head movement: calibrating optic flow with extra-retinal information

    E-Print Network [OSTI]

    Fah, Cheong Loong

    Absolute distance perception during in-depth head movement: calibrating optic flow with extra-retinal Processing and Application Laboratory (IPAL-CNRS), KDRL, 21 Heng Mui Keng Terrace, Singapore 119613 d reserved. Keywords: Self-motion; Object-motion; Absolute distance perception; Optic flow; Extra-retinal cue

  19. Gravitational microlensing of quasar broad line regions at large optical depths

    E-Print Network [OSTI]

    Geraint F. Lewis; Rodrigo A. Ibata

    2003-10-29

    Recent estimates of the scale of structures at the heart of quasars suggest that the region responsible for the broad line emission are smaller than previously thought. With this revision of scale, the broad line region is amenable to the influence of gravitational microlensing. This study investigates the influence on microlensing at high optical depth on a number of current models of the Broad Line Region (BLR). It is found that the BLR can be significantly magnified by the action of microlensing, although the degree of magnification is dependent upon spatial and kinematic structure of the BLR. Furthermore, while there is a correlation between the microlensing fluctuations of the continuum source and the BLR, there is substantial scatter about this relation, revealing that broadband photometric monitoring is not necessarily a guide to microlensing of the BLR. The results of this study demonstrate that the spatial and kinematic structure within the BLR may be determined via spectroscopic monitoring of microlensed quasars.

  20. Surface aerosol radiative forcing derived from collocated ground-based radiometric

    E-Print Network [OSTI]

    Liou, K. N.

    Surface aerosol radiative forcing derived from collocated ground-based radiometric observations-Filter Rotating Shadowband Radiometer data match closely with those from the Cimel sun- photometer data for two of the sunphotometer to retrieve aerosol optical depths, a, along with observed surface flux data from field campaigns

  1. A geostatistical data fusion technique for merging remote sensing and groundbased observations of aerosol optical thickness

    E-Print Network [OSTI]

    Michalak, Anna M.

    that aerosols contrib- ute significantly to reflected solar radiation (the aerosol direct effect) and modify of aerosols in climate and atmospheric chemistry. To date, however, there have been only limited attempts of the growing concentrations of CO2 and other greenhouse gases. Although the radiative forcing of aerosols

  2. Novel Technique for the CO2 Laser Fabrication of Optical Devices with Sub-Micrometer Ablation Depth Precision

    E-Print Network [OSTI]

    a strong wavelength and temperature dependence 5 . In this work a 100 W, pulse width modulated (PWM), CO2Novel Technique for the CO2 Laser Fabrication of Optical Devices with Sub-Micrometer Ablation Depth techniques for the processing of fibre end face and cladding surfaces using a 9.6 µm CO2 laser. We

  3. RETRIEVALS OF CLOUD OPTICAL DEPTH AND EFFECTIVE RADIUS FROM A THIN-CLOUD ROTATING SHADOWBAND RADIOMETER (TC-RSR)

    E-Print Network [OSTI]

    RETRIEVALS OF CLOUD OPTICAL DEPTH AND EFFECTIVE RADIUS FROM A THIN-CLOUD ROTATING SHADOWBAND Division Brookhaven National Laboratory U.S. Department of Energy Office of Science ABSTRACT A thin cloud cloud. We applied Min and Duan's retrieval algorithm to the field measurements of TC-RSR to derive cloud

  4. Optical and thermal depth profile reconstructions of inhomogeneous photopolymerization in dental resins using photothermal waves

    E-Print Network [OSTI]

    Mandelis, Andreas

    by a blue light-emitting diode, the x and x depth profiles were reconstructed from photothermal radiometric

  5. Investigation of the optical and cloud forming properties of pollution, biomass burning, and mineral dust aerosols 

    E-Print Network [OSTI]

    Lee, Yong Seob

    2006-08-16

    that were observed during this period. The predicted cloud condensation nuclei concentrations were used in a cloud model to determine the impact of the different aerosol types on the expected cloud droplet concentration. RH-dependent aerosol extinction...

  6. Optical depth measurements by shadow-band radiometers and their uncertainties

    E-Print Network [OSTI]

    derived from Aerosol Robotic Net- work (AERONET) CIMEL tracking Sun photometer data to 0 is essentially the same: 0.01 in OD [3]. Like the tracking Sun photometers, shadow-band instruments have some important product of Sun-photometric measurements. [According to the American Meteoro- logical Society (AMS

  7. The optical depth of the Universe to ultrahigh energy cosmic ray scattering in the magnetized large scale structure

    E-Print Network [OSTI]

    Kumiko Kotera; Martin Lemoine

    2008-04-30

    This paper provides an analytical description of the transport of ultrahigh energy cosmic rays in an inhomogeneously magnetized intergalactic medium. This latter is modeled as a collection of magnetized scattering centers such as radio cocoons, magnetized galactic winds, clusters or magnetized filaments of large scale structure, with negligible magnetic fields in between. Magnetic deflection is no longer a continuous process, it is rather dominated by scattering events. We study the interaction between high energy cosmic rays and the scattering agents. We then compute the optical depth of the Universe to cosmic ray scattering and discuss the phenomological consequences for various source scenarios. For typical parameters of the scattering centers, the optical depth is greater than unity at 5x10^{19}eV, but the total angular deflection is smaller than unity. One important consequence of this scenario is the possibility that the last scattering center encountered by a cosmic ray be mistaken with the source of this cosmic ray. In particular, we suggest that part of the correlation recently reported by the Pierre Auger Observatory may be affected by such delusion: this experiment may be observing in part the last scattering surface of ultrahigh energy cosmic rays rather than their source population. Since the optical depth falls rapidly with increasing energy, one should probe the arrival directions of the highest energy events beyond 10^{20}eV on an event by event basis to circumvent this effect.

  8. Near-infrared fluorescence enhanced optical imaging: an analysis of penetration depth 

    E-Print Network [OSTI]

    Houston, Jessica Perea

    2002-01-01

    , but also may facilitate cancer staging and increase our understanding of tumor progression. Frequency domain photon migration imaging (FDPM) is a maturing optical tool that is based upon the propagation of near infrared (NIR) radiation through tissue...

  9. On the Depth Information in the Point Spread Function of a Defocused Optical System

    E-Print Network [OSTI]

    Subbarao, Murali "Rao"

    is determined by paraxial geometric op­ tics. In this paper we show that oe 2 w = oe 2 g + oe 2 0 . Consequently by paraxial geometric optics. We also compare here the PSF determined by paraxial geometric op­ tics

  10. Simulated aerosol key optical properties over global scale using an aerosol transport model coupled with a new type of dynamic core

    E-Print Network [OSTI]

    Dong, Xiquan

    effects: (a) a direct effect in which aerosol particles scatter and absorb the solar and thermal radiation Atmospheric aerosols greatly impact the Earth's climate in many ways, and to date, not all of them are well

  11. Aerosol Retrievals from ARM SGP MFRSR Data

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Alexandrov, Mikhail

    2008-01-15

    The Multi-Filter Rotating Shadowband Radiometer (MFRSR) makes precise simultaneous measurements of the solar direct normal and diffuse horizontal irradiances at six wavelengths (nominally 415, 500, 615, 673, 870, and 940 nm) at short intervals (20 sec for ARM instruments) throughout the day. Time series of spectral optical depth are derived from these measurements. Besides water vapor at 940 nm, the other gaseous absorbers within the MFRSR channels are NO2 (at 415, 500, and 615 nm) and ozone (at 500, 615, and 670 nm). Aerosols and Rayleigh scattering contribute atmospheric extinction in all MFRSR channels. Our recently updated MFRSR data analysis algorithm allows us to partition the spectral aerosol optical depth into fine and coarse modes and to retrieve the fine mode effective radius. In this approach we rely on climatological amounts of NO2 from SCIAMACHY satellite retrievals and use daily ozone columns from TOMS.

  12. Aerosol Retrievals from ARM SGP MFRSR Data

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Alexandrov, Mikhail

    The Multi-Filter Rotating Shadowband Radiometer (MFRSR) makes precise simultaneous measurements of the solar direct normal and diffuse horizontal irradiances at six wavelengths (nominally 415, 500, 615, 673, 870, and 940 nm) at short intervals (20 sec for ARM instruments) throughout the day. Time series of spectral optical depth are derived from these measurements. Besides water vapor at 940 nm, the other gaseous absorbers within the MFRSR channels are NO2 (at 415, 500, and 615 nm) and ozone (at 500, 615, and 670 nm). Aerosols and Rayleigh scattering contribute atmospheric extinction in all MFRSR channels. Our recently updated MFRSR data analysis algorithm allows us to partition the spectral aerosol optical depth into fine and coarse modes and to retrieve the fine mode effective radius. In this approach we rely on climatological amounts of NO2 from SCIAMACHY satellite retrievals and use daily ozone columns from TOMS.

  13. Electromagnetically induced transparency and four-wave mixing in a cold atomic ensemble with large optical depth

    E-Print Network [OSTI]

    J. Geng; G. T. Campbell; J. Bernu; D. Higginbottom; B. M. Sparkes; S. M. Assad; W. P. Zhang; N. P. Robins; P. K. Lam; B. C. Buchler

    2014-08-11

    We report on the delay of optical pulses using electromagnetically induced transparency in an ensemble of cold atoms with an optical depth exceeding 500. To identify the regimes in which four-wave mixing impacts on EIT behaviour, we conduct the experiment in both rubidium 85 and rubidium 87. Comparison with theory shows excellent agreement in both isotopes. In rubidium 87, negligible four-wave mixing was observed and we obtained one pulse-width of delay with 50% efficiency. In rubidium 85, four-wave-mixing contributes to the output. In this regime we achieve a delay-bandwidth product of 3.7 at 50% efficiency, allowing temporally multimode delay, which we demonstrate by compressing two pulses into the memory medium.

  14. Variations in organic aerosol optical and hygroscopic properties upon heterogeneous OH oxidation

    E-Print Network [OSTI]

    Cappa, Christopher D.

    Measurements of the evolution of organic aerosol extinction cross sections (?[subscript ext]) and subsaturated hygroscopicity upon heterogeneous OH oxidation are reported for two model compounds, squalane (a C30 saturated ...

  15. WRF-Chem Simulations of Aerosols and Anthropogenic Aerosol Radiative Forcing in East Asia

    SciTech Connect (OSTI)

    Gao, Yi; Zhao, Chun; Liu, Xiaohong; Zhang, Meigen; Leung, Lai-Yung R.

    2014-08-01

    This study aims to provide a first comprehensive evaluation of WRF-Chem for modeling aerosols and anthropogenic aerosol radiative forcing (RF) over East Asia. Several numerical experiments were conducted from November 2007 to December 2008. Comparison between model results and observations shows that the model can generally reproduce the observed spatial distributions of aerosol concentration, aerosol optical depth (AOD) and single scattering albedo (SSA) from measurements at different sites, including the relatively higher aerosol concentration and AOD over East China and the relatively lower AOD over Southeast Asia, Korean, and Japan. The model also depicts the seasonal variation and transport of pollutions over East Asia. Particulate matter of 10 um or less in the aerodynamic diameter (PM10), black carbon (BC), sulfate (SO42-), nitrate (NO3-) and ammonium (NH4+) concentrations are higher in spring than other seasons in Japan due to the pollutant transport from polluted area of East Asia. AOD is high over Southwest and Central China in winter, spring and autumn and over North China in summer while is low over South China in summer due to monsoon precipitation. SSA is lowest in winter and highest in summer. The model also captures the dust events at the Zhangye site in the semi-arid region of China. Anthropogenic aerosol RF is estimated to range from -5 to -20 W m-2 over land and -20 to -40 W m-2 over ocean at the top of atmosphere (TOA), 5 to 30 W m-2 in the atmosphere (ATM) and -15 to -40 W m-2 at the bottom (BOT). The warming effect of anthropogenic aerosol in ATM results from BC aerosol while the negative aerosol RF at TOA is caused by scattering aerosols such as SO4 2-, NO3 - and NH4+. Positive BC RF at TOA compensates 40~50% of the TOA cooling associated with anthropogenic aerosol.

  16. In-depth analysis of CIGS film for solar cells, structural and optical characterization

    E-Print Network [OSTI]

    Slobodskyy, A; ~Ulyanenkova, T; ~Doyle, S; Powalla, M; ~Baumbach, T; ~Lemmer, U

    2010-01-01

    Space-resolved X-ray diffraction measurements performed on gradient-etched CuIn$_{1-x}$Ga$_x$Se$_2$ (CIGS) solar cells provide information about stress and texture depth profiles in the absorber layer. An important parameter for CIGS layer growth dynamics, the absorber thickness-dependent stress in the molybdenum back contact is analyzed. Texturing of grains and quality of the polycrystalline absorber layer are correlated with the intentional composition gradients (band gap grading). Band gap gradient is determined by space-resolved photoluminescence measurements and correlated with composition and strain profiles.

  17. The Two-Column Aerosol Project (TCAP) Science Plan

    SciTech Connect (OSTI)

    Berkowitz, CM; Berg, LK; Cziczo, DJ; Flynn, CJ; Kassianov, EI; Fast, JD; Rasch, PJ; Shilling, JE; Zaveri, RA; Zelenyuk, A; Ferrare, RA; Hostetler, CA; Cairns, B; Russell, PB; Ervens, B

    2011-07-27

    The Two-Column Aerosol Project (TCAP) field campaign will provide a detailed set of observations with which to (1) perform radiative and cloud condensation nuclei (CCN) closure studies, (2) evaluate a new retrieval algorithm for aerosol optical depth (AOD) in the presence of clouds using passive remote sensing, (3) extend a previously developed technique to investigate aerosol indirect effects, and (4) evaluate the performance of a detailed regional-scale model and a more parameterized global-scale model in simulating particle activation and AOD associated with the aging of anthropogenic aerosols. To meet these science objectives, the Atmospheric Radiation Measurement (ARM) Climate Research Facility will deploy the ARM Mobile Facility (AMF) and the Mobile Aerosol Observing System (MAOS) on Cape Cod, Massachusetts, for a 12-month period starting in the summer of 2012 in order to quantify aerosol properties, radiation, and cloud characteristics at a location subject to both clear and cloudy conditions, and clean and polluted conditions. These observations will be supplemented by two aircraft intensive observation periods (IOPs), one in the summer and a second in the winter. Each IOP will deploy one, and possibly two, aircraft depending on available resources. The first aircraft will be equipped with a suite of in situ instrumentation to provide measurements of aerosol optical properties, particle composition and direct-beam irradiance. The second aircraft will fly directly over the first and use a multi-wavelength high spectral resolution lidar (HSRL) and scanning polarimeter to provide continuous optical and cloud properties in the column below.

  18. Aerosol mobility size spectrometer

    DOE Patents [OSTI]

    Wang, Jian (Port Jefferson, NY); Kulkarni, Pramod (Port Jefferson Station, NY)

    2007-11-20

    A device for measuring aerosol size distribution within a sample containing aerosol particles. The device generally includes a spectrometer housing defining an interior chamber and a camera for recording aerosol size streams exiting the chamber. The housing includes an inlet for introducing a flow medium into the chamber in a flow direction, an aerosol injection port adjacent the inlet for introducing a charged aerosol sample into the chamber, a separation section for applying an electric field to the aerosol sample across the flow direction and an outlet opposite the inlet. In the separation section, the aerosol sample becomes entrained in the flow medium and the aerosol particles within the aerosol sample are separated by size into a plurality of aerosol flow streams under the influence of the electric field. The camera is disposed adjacent the housing outlet for optically detecting a relative position of at least one aerosol flow stream exiting the outlet and for optically detecting the number of aerosol particles within the at least one aerosol flow stream.

  19. Constraining the atmospheric composition of the day-night terminators of HD 189733b: Atmospheric retrieval with aerosols

    SciTech Connect (OSTI)

    Lee, Jae-Min; Irwin, Patrick G. J.; Fletcher, Leigh N.; Barstow, Joanna K.; Heng, Kevin

    2014-07-01

    A number of observations have shown that Rayleigh scattering by aerosols dominates the transmission spectrum of HD 189733b at wavelengths shortward of 1 ?m. In this study, we retrieve a range of aerosol distributions consistent with transmission spectroscopy between 0.3-24 ?m that were recently re-analyzed by Pont et al. To constrain the particle size and the optical depth of the aerosol layer, we investigate the degeneracies between aerosol composition, temperature, planetary radius, and molecular abundances that prevent unique solutions for transit spectroscopy. Assuming that the aerosol is composed of MgSiO{sub 3}, we suggest that a vertically uniform aerosol layer over all pressures with a monodisperse particle size smaller than about 0.1 ?m and an optical depth in the range 0.002-0.02 at 1 ?m provides statistically meaningful solutions for the day/night terminator regions of HD 189733b. Generally, we find that a uniform aerosol layer provide adequate fits to the data if the optical depth is less than 0.1 and the particle size is smaller than 0.1 ?m, irrespective of the atmospheric temperature, planetary radius, aerosol composition, and gaseous molecules. Strong constraints on the aerosol properties are provided by spectra at wavelengths shortward of 1 ?m as well as longward of 8 ?m, if the aerosol material has absorption features in this region. We show that these are the optimal wavelengths for quantifying the effects of aerosols, which may guide the design of future space observations. The present investigation indicates that the current data offer sufficient information to constrain some of the aerosol properties of HD189733b, but the chemistry in the terminator regions remains uncertain.

  20. Atmospheric optical calibration system

    DOE Patents [OSTI]

    Hulstrom, Roland L. (Bloomfield, CO); Cannon, Theodore W. (Golden, CO)

    1988-01-01

    An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions.

  1. Atmospheric optical calibration system

    DOE Patents [OSTI]

    Hulstrom, R.L.; Cannon, T.W.

    1988-10-25

    An atmospheric optical calibration system is provided to compare actual atmospheric optical conditions to standard atmospheric optical conditions on the basis of aerosol optical depth, relative air mass, and diffuse horizontal skylight to global horizontal photon flux ratio. An indicator can show the extent to which the actual conditions vary from standard conditions. Aerosol scattering and absorption properties, diffuse horizontal skylight to global horizontal photon flux ratio, and precipitable water vapor determined on a real-time basis for optical and pressure measurements are also used to generate a computer spectral model and for correcting actual performance response of a photovoltaic device to standard atmospheric optical condition response on a real-time basis as the device is being tested in actual outdoor conditions. 7 figs.

  2. Combined Daily Monitoring of Aerosol Optical Depths and Water Vapour Column Content during LACE 98 and LITFASS 98 Experiments

    E-Print Network [OSTI]

    Novikov, V V; Alekseeva, G A; Galkin, V D; Güldner, J; Naebert, T; Service, German Weather; Observatory, Meteorological; Lindenberg,; Germany,; Sciences, Russian Academy of; Observatory, Pulkovo; Petersburg, St; Russia,

    2010-01-01

    During summer of 1998 two large-scale complex campaigns, LITFASS98 (May 25th to June 22nd) and LACE98 (July 13th to August 14th), took place at the Meteorological Observatory Lindenberg (MOL). The aim of both experiments focus on the intensive daily observations of atmospheric conditions and the determination of their fundamental meteorological parameters in the vertical column over Lindenberg (Lindenberg's Column). About 20 German research institutions and addition one from the Netherlands, Austria and Russia participated at the experiments. A wide variety of ground-based instruments was operated in Lindenberg and Falkenberg, including LIDARs, microwave radiometer and radiosondes complemented by tethered balloons and aircraft measurements. For the first time the star- and sunphotometer of MOL were used together with other geophysical tools. The observations with both photometers were carried out practically every day and night except during absolutely overcast conditions. The observed data were processed imm...

  3. A Measurement of Time-Averaged Aerosol Optical Depth using Air-Showers Observed in Stereo by HiRes

    E-Print Network [OSTI]

    Res R.U. Abbasi,1 T. Abu-Zayyad,1 J.F. Amann,2 G. Archbold,1 R. Atkins,1 K. Belov,1 J.W. Belz,3 S. BenZvi,5 D.R. Bergman,6 J.H. Boyer,4 C.T. Cannon,1 Z. Cao,1 B.M. Connolly,5 Y. Fedorova,1 C.B. Finley,5 W.C. Knapp,4 E.C. Loh,1 N. Manago,7 E.J. Mannel,4 K. Martens,1 J.A.J. Matthews,8 J.N. Matthews,1 A. O'Neill,5

  4. Source Characterization from Ambient Measurements of Aerosol Optical Christopher D. Cappa1

    E-Print Network [OSTI]

    a given particle absorbs or scatters light depends explicitly on the particle composition and mixing state emissions, while light scattering aerosols are produced from both primary and secondary (gas-to-particle conversion of natural and anthropogenic gaseous precursors) sources [Ghan and Schwartz, 2007]. The chemical

  5. Variability of aerosol optical depth and aerosol forcing over India S. Sarkar, R. Chokngamwong, G. Cervone, R.P. Singh *, M. Kafatos

    E-Print Network [OSTI]

    Singh, Ramesh P.

    . Cervone, R.P. Singh *, M. Kafatos Centre for Earth Observing and Space Research, School of Computational is centrally located in the Indo-Gangetic basin. Recently, Singh et al. (2004) have discussed the annual-mail addresses: rsingh3@gmu.edu, rpalka425@gmail.com (R.P. Singh). www.elsevier.com/locate/asr Advances in Space

  6. Computing and Partitioning Cloud Feedbacks Using Cloud Property Histograms. Part II: Attribution to Changes in Cloud Amount, Altitude, and Optical Depth

    E-Print Network [OSTI]

    Hartmann, Dennis

    Computing and Partitioning Cloud Feedbacks Using Cloud Property Histograms. Part II: Attribution to Changes in Cloud Amount, Altitude, and Optical Depth MARK D. ZELINKA Department of Atmospheric Sciences received 12 May 2011, in final form 15 November 2011) ABSTRACT Cloud radiative kernels and histograms

  7. Production Mechanism, Number Concentration, Size Distribution, Chemical Composition, and Optical Properties of Sea Spray Aerosols Workshop, Summer 2012

    SciTech Connect (OSTI)

    Meskhidze, Nicholas [NCSU] [NCSU

    2013-10-21

    The objective of this workshop was to address the most urgent open science questions for improved quantification of sea spray aerosol-radiation-climate interactions. Sea spray emission and its influence on global climate remains one of the most uncertain components of the aerosol-radiation-climate problem, but has received less attention than other aerosol processes (e.g. production of terrestrial secondary organic aerosols). Thus, the special emphasis was placed on the production flux of sea spray aerosol particles, their number concentration and chemical composition and properties.

  8. Assessing the Effects of Anthropogenic Aerosols on Pacific Storm Track Using a Multiscale Global Climate Model

    SciTech Connect (OSTI)

    Wang, Yuan; Wang, Minghuai; Zhang, Renyi; Ghan, Steven J.; Lin, Yun; Hu, Jiaxi; Pan, Bowen; Levy, Misti; Jiang, Jonathan; Molina, Mario J.

    2014-05-13

    Atmospheric aerosols impact weather and global general circulation by modifying cloud and precipitation processes, but the magnitude of cloud adjustment by aerosols remains poorly quantified and represents the largest uncertainty in estimated forcing of climate change. Here we assess the impacts of anthropogenic aerosols on the Pacific storm track using a multi-scale global aerosol-climate model (GCM). Simulations of two aerosol scenarios corresponding to the present day and pre-industrial conditions reveal long-range transport of anthropogenic aerosols across the north Pacific and large resulting changes in the aerosol optical depth, cloud droplet number concentration, and cloud and ice water paths. Shortwave and longwave cloud radiative forcing at the top of atmosphere are changed by - 2.5 and + 1.3 W m-2, respectively, by emission changes from pre-industrial to present day, and an increased cloud-top height indicates invigorated mid-latitude cyclones. The overall increased precipitation and poleward heat transport reflect intensification of the Pacific storm track by anthropogenic aerosols. Hence, this work provides for the first time a global perspective of the impacts of Asian pollution outflows from GCMs. Furthermore, our results suggest that the multi-scale modeling framework is essential in producing the aerosol invigoration effect of deep convective clouds on the global scale.

  9. Science Overview Document Indirect and Semi-Direct Aerosol Campaign (ISDAC) April 2008

    SciTech Connect (OSTI)

    SJ Ghan; B Schmid; JM Hubbe; CJ Flynn; A Laskin; AA Zelenyuk; DJ Czizco; CN Long; G McFarquhar; J Verlinde; J Harrington; JW Strapp; P Liu; A Korolev; A McDonald; M Wolde; A Fridlind; T Garrett; G Mace; G Kok; S Brooks; D Collins; D Lubin; P Lawson; M Dubey; C Mazzoleni; M Shupe; S Xie; DD Turner; Q Min; EJ Mlawer; D Mitchell

    2007-11-01

    The ARM Climate Research Facility’s (ACRF) Aerial Vehicle Program (AVP) will deploy an intensive cloud and aerosol observing system to the ARM North Slope of Alaska (NSA) locale for a five week Indirect and Semi-Direct Aerosol Campaign (ISDAC) during period 29 March through 30 April 2008. The deployment period is within the International Polar Year, thus contributing to and benefiting from the many ancillary observing systems collecting data synergistically. We will deploy the Canadian National Research Council Convair 580 aircraft to measure temperature, humidity, total particle number, aerosol size distribution, single particle composition, concentrations of cloud condensation nuclei and ice nuclei, optical scattering and absorption, updraft velocity, cloud liquid water and ice contents, cloud droplet and crystal size distributions, cloud particle shape, and cloud extinction. In addition to these aircraft measurements, ISDAC will deploy two instruments at the ARM site in Barrow: a spectroradiometer to retrieve cloud optical depth and effective radius, and a tandem differential mobility analyzer to measure the aerosol size distribution and hygroscopicity. By using many of the same instruments used during Mixed-Phase Arctic Cloud Experiment (M-PACE), conducted in October 2004, we will be able to contrast the arctic aerosol and cloud properties during the fall and spring transitions. The aerosol measurements can be used in cloud models driven by objectively analyzed boundary conditions to test whether the cloud models can simulate the aerosol influence on the clouds. The influence of aerosol and boundary conditions on the simulated clouds can be separated by running the cloud models with all four combinations of M-PACE and ISDAC aerosol and boundary conditions: M-PACE aerosol and boundary conditions, M-PACE aerosol and ISDAC boundary conditions, ISDAC aerosol and M-PACE boundary conditions, and ISDAC aerosol and boundary conditions. ISDAC and M-PACE boundary conditions are likely to be very different because of the much more extensive ocean water during M-PACE. The uniformity of the surface conditions during ISDAC greatly simplifies the objective analysis (surface fluxes and precipitation are very weak), so that it can largely rely on the European Centre for Medium-Range Weather Forecasts analysis. The aerosol measurements can also be used as input to the cloud models and to evaluate the aerosol retrievals. By running the cloud models with and without solar absorption by the aerosols, we can determine the semidirect effect of the aerosol on the clouds.

  10. Effects of Ocean Ecosystem on Marine Aerosol-Cloud Interaction

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Meskhidze, Nicholas; Nenes, Athanasios

    2010-01-01

    Using satellite data for the surface ocean, aerosol optical depth (AOD), and cloud microphysical parameters, we show that statistically significant positive correlations exist between ocean ecosystem productivity, the abundance of submicron aerosols, and cloud microphysical properties over different parts of the remote oceans. The correlation coefficient for remotely sensed surface chlorophyll a concentration ([Chl- a ]) and liquid cloud effective radii over productive areas of the oceans varies between ? 0.2 and ? 0.6 . Special attention is given to identifying (and addressing) problems from correlation analysis used in the previousmore »studies that can lead to erroneous conclusions. A new approach (using the difference between retrieved AOD and predicted sea salt aerosol optical depth, AOD diff ) is developed to explore causal links between ocean physical and biological systems and the abundance of cloud condensation nuclei (CCN) in the remote marine atmosphere. We have found that over multiple time periods, 550?nm AOD diff (sensitive to accumulation mode aerosol, which is the prime contributor to CCN) correlates well with [Chl- a ] over the productive waters of the Southern Ocean. Since [Chl- a ] can be used as a proxy of ocean biological productivity, our analysis demonstrates the role of ocean ecology in contributing CCN, thus shaping the microphysical properties of low-level marine clouds. « less

  11. Aerosol Observing System (AOS) Handbook

    SciTech Connect (OSTI)

    Jefferson, A

    2011-01-17

    The Aerosol Observing System (AOS) is a suite of in situ surface measurements of aerosol optical and cloud-forming properties. The instruments measure aerosol properties that influence the earth’s radiative balance. The primary optical measurements are those of the aerosol scattering and absorption coefficients as a function of particle size and radiation wavelength and cloud condensation nuclei (CCN) measurements as a function of percent supersaturation. Additional measurements include those of the particle number concentration and scattering hygroscopic growth. Aerosol optical measurements are useful for calculating parameters used in radiative forcing calculations such as the aerosol single-scattering albedo, asymmetry parameter, mass scattering efficiency, and hygroscopic growth. CCN measurements are important in cloud microphysical models to predict droplet formation.

  12. Biomass burning and pollution aerosol over North America: Organic components and their influence on spectral optical properties and

    E-Print Network [OSTI]

    Clarke, Antony

    Biomass burning and pollution aerosol over North America: Organic components and their influence Received 11 July 2006; revised 5 April 2007; accepted 19 April 2007; published 9 June 2007. [1] Thermal and pollution plumes identified from trace gas measurements were evaluated for their aerosol physiochemical

  13. Depth-resolved monitoring of diffusion of hyperosmotic agents in normal and malignant human esophagus tissues using optical coherence tomography in-vitro

    SciTech Connect (OSTI)

    Zhao Qingliang; Guo Zhouyi; Wei Huajiang; Yang Hongqin; Xie Shusen

    2011-10-31

    Depth-resolved monitoring with differentiation and quantification of glucose diffusion in healthy and abnormal esophagus tissues has been studied in vitro. Experiments have been performed using human normal esophagus and esophageal squamous cell carcinoma (ESCC) tissues by the optical coherence tomography (OCT). The images have been continuously acquired for 120 min in the experiments, and the depth-resolved and average permeability coefficients of the 40 % glucose solution have been calculated by the OCT amplitude (OCTA) method. We demonstrate the capability of the OCT technique for depth-resolved monitoring, differentiation, and quantifying of glucose diffusion in normal esophagus and ESCC tissues. It is found that the permeability coefficients of the 40 % glucose solution are not uniform throughout the normal esophagus and ESCC tissues and increase from (3.30 {+-} 0.09) Multiplication-Sign 10{sup -6} and (1.57 {+-} 0.05) Multiplication-Sign 10{sup -5} cm s{sup -1} at the mucous membrane of normal esophagus and ESCC tissues to (1.82 {+-} 0.04) Multiplication-Sign 10{sup -5} and (3.53 {+-} 0.09) Multiplication-Sign 10{sup -5} cm s{sup -1} at the submucous layer approximately 742 {mu}m away from the epithelial surface of normal esophagus and ESCC tissues, respectively. (optical coherence tomography)

  14. Sensitivity Study of the Effects of Mineral Dust Particle Nonsphericity and Thin Cirrus Clouds on MODIS Dust Optical Depth Retrievals and Direct Radiative Forcing Calculations 

    E-Print Network [OSTI]

    Feng, Qian

    2011-10-21

    A special challenge posed by mineral dust aerosols is associated with their predominantly nonspherical particle shapes. In the present study, the scattering and radiative properties for nonspherical mineral dust aerosols at violet-to-blue (0.412, 0...

  15. Direct and semidirect aerosol effects of Southern African biomass burning aerosol

    SciTech Connect (OSTI)

    Sakaeda, Naoko; Wood, Robert; Rasch, Philip J.

    2011-06-21

    The direct and semi-direct radiative effects of biomass burning aerosols from Southern African fires during July-October are investigated using 20 year runs of the Community Atmospheric Model (CAM) coupled to a slab ocean model. The aerosol optical depth is constrained using observations in clear skies from MODIS and for aerosol layers above clouds from CALIPSO. Over the ocean, where the absorbing biomass burning aerosol layers are primarily located above cloud, negative top of atmosphere (TOA) semi-direct radiative effects associated with increased low cloud cover dominate over a weaker positive all-sky direct radiative effect (DRE). In contrast, over the land where the aerosols are often below or within cloud layers, reductions in cloud liquid water path (LWP) lead to a positive semi-direct radiative effect that dominates over a near-zero DRE. Over the ocean, the cloud response can be understood as a response to increased lower tropospheric stability (LTS) which is caused both by aerosol absorptive warming in overlying layers and surface cooling in response to direct aerosol forcing. The ocean cloud changes are robust to changes in the cloud parameterization (removal of the hard-wired dependence of clouds on LTS), suggesting that they are physically realistic. Over land where cloud cover changes are minimal, decreased LWP is consistent with weaker convection driven by increased static stability. Over the entire region the overall TOA radiative effect from the biomass burning aerosols is almost zero due to opposing effects over the land and ocean. However, the surface forcing is strongly negative requiring a reduction in precipitation. This is primarily realized through reductions in convective precipitation on both the southern and northern flanks of the convective precipitation region spanning the equatorial rainforest and the ITCZ in the southern Sahel. The changes are consistent with the low-level aerosol forced cooling pattern. The results highlight the importance of semi-direct radiative effects and precipitation responses for determining the climatic effects of aerosols in the African region.

  16. Aerosols and their influence on radiation partitioning and savanna productivity in northern Australia

    SciTech Connect (OSTI)

    Kanniah, K. D.; Beringer, J.; Tapper, N. J.; Long, Charles N.

    2010-05-01

    We investigated the effect of aerosols and clouds on the Net Ecosystem Productivity (NEP) of savannas in northern Australia using aerosol optical depth, clouds and radiation data from the Atmospheric Radiation Measurement (ARM) site in Darwin and carbon flux data measured from eddy covariance techniques from a site at Howard Springs, 35km southeast of Darwin. Generally we found that the concentration of aerosols in this region was relatively low than observed at other sites, therefore the proportion of diffuse radiation reaching the earths surface was only ~ 30%. As a result, we observed only a modest change in carbon uptake under aerosol laden skies and there was no significant difference for dry season Radiation Use Efficiency (RUE) between clear sky, aerosols or thin clouds. On the other hand thick clouds in the wet season produce much more diffuse radiation than aerosols or thin clouds and therefore the initial canopy quantum efficiency was seen to increase 45 and 2.5 times more than under thin clouds and aerosols respectively. The normalized carbon uptake under thick clouds is 57% and 50% higher than under aerosols and thin clouds respectively even though the total irradiance received under thick clouds was reduced 59% and 50% than under aerosols and thin clouds respectively. However, reduction in total irradiance decreases the mean absolute carbon uptake as much as 22% under heavy cloud cover compared to thin clouds or aerosols. Thus, any increase in aerosol concentration or cloud cover that can enhance the diffuse component may have large impacts on productivity in this region.

  17. Ganges Valley Aerosol Experiment: Science and Operations Plan

    SciTech Connect (OSTI)

    Kotamarthi, VR

    2010-06-21

    The Ganges Valley region is one of the largest and most rapidly developing sections of the Indian subcontinent. The Ganges River, which provides the region with water needed for sustaining life, is fed primarily by snow and rainfall associated with Indian summer monsoons. Impacts of changes in precipitation patterns, temperature, and the flow of the snow-fed rivers can be immense. Recent satellite-based measurements have indicated that the upper Ganges Valley has some of the highest persistently observed aerosol optical depth values. The aerosol layer covers a vast region, extending across the Indo-Gangetic Plain to the Bay of Bengal during the winter and early spring of each year. The persistent winter fog in the region is already a cause of much concern, and several studies have been proposed to understand the economic, scientific, and societal dimensions of this problem. During the INDian Ocean EXperiment (INDOEX) field studies, aerosols from this region were shown to affect cloud formation and monsoon activity over the Indian Ocean. This is one of the few regions showing a trend toward increasing surface dimming and enhanced mid-tropospheric warming. Increasing air pollution over this region could modify the radiative balance through direct, indirect, and semi-indirect effects associated with aerosols. The consequences of aerosols and associated pollution for surface insolation over the Ganges Valley and monsoons, in particular, are not well understood. The proposed field study is designed for use of (1) the ARM Mobile Facility (AMF) to measure relevant radiative, cloud, convection, and aerosol optical characteristics over mainland India during an extended period of 9–12 months and (2) the G-1 aircraft and surface sites to measure relevant aerosol chemical, physical, and optical characteristics in the Ganges Valley during a period of 6–12 weeks. The aerosols in this region have complex sources, including burning of coal, biomass, and biofuels; automobile emissions; and dust. The extended AMF deployment will enable measurements under different regimes of the climate and aerosol abundance—in the wet monsoon period with low aerosol loading; in the dry, hot summer with aerosols dispersed throughout the atmospheric column; and in the cool, dry winter with aerosols confined mostly to the boundary later and mid-troposphere. Each regime, in addition, has its own distinct radiative and atmospheric dynamic drivers. The aircraft operational phase will assist in characterizing the aerosols at times when they have been observed to be at the highest concentrations. A number of agencies in India will collaborate with the proposed field study and provide support in terms of planning, aircraft measurements, and surface sites. The high concentration of aerosols in the upper Ganges Valley, together with hypotheses involving several possible mechanisms with direct impacts on the hydrologic cycle of the region, gives us a unique opportunity to generate data sets that will be useful both in understanding the processes at work and in providing answers regarding the effects of aerosols on climate in a region where the perturbation is the highest.

  18. Assessing regional scale predictions of aerosols, marine stratocumulus, and their interactions during VOCALS-REx using WRF-Chem

    SciTech Connect (OSTI)

    Yang Q.; Lee Y.; Gustafson Jr., W. I.; Fast, J. D.; Wang, H.; Easter, R. C.; Morrison, H.; Chapman, E. G.; Spak, S. N.; Mena-Carrasco, M. A.

    2011-12-02

    This study assesses the ability of the recent chemistry version (v3.3) of the Weather Research and Forecasting (WRF-Chem) model to simulate boundary layer structure, aerosols, stratocumulus clouds, and energy fluxes over the Southeast Pacific Ocean. Measurements from the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) and satellite retrievals (i.e., products from the MODerate resolution Imaging Spectroradiometer (MODIS), Clouds and Earth's Radiant Energy System (CERES), and GOES-10) are used for this assessment. The Morrison double-moment microphysics scheme is newly coupled with interactive aerosols in the model. The 31-day (15 October-16 November 2008) WRF-Chem simulation with aerosol-cloud interactions (AERO hereafter) is also compared to a simulation (MET hereafter) with fixed cloud droplet number concentrations in the microphysics scheme and simplified cloud and aerosol treatments in the radiation scheme. The well-simulated aerosol quantities (aerosol number, mass composition and optical properties), and the inclusion of full aerosol-cloud couplings lead to significant improvements in many features of the simulated stratocumulus clouds: cloud optical properties and microphysical properties such as cloud top effective radius, cloud water path, and cloud optical thickness. In addition to accounting for the aerosol direct and semi-direct effects, these improvements feed back to the simulation of boundary-layer characteristics and energy budgets. Particularly, inclusion of interactive aerosols in AERO strengthens the temperature and humidity gradients within the capping inversion layer and lowers the marine boundary layer (MBL) depth by 130 m from that of the MET simulation. These differences are associated with weaker entrainment and stronger mean subsidence at the top of the MBL in AERO. Mean top-of-atmosphere outgoing shortwave fluxes, surface latent heat, and surface downwelling longwave fluxes are in better agreement with observations in AERO, compared to the MET simulation. Nevertheless, biases in some of the simulated meteorological quantities (e.g., MBL temperature and humidity) and aerosol quantities (e.g., underestimations of accumulation mode aerosol number) might affect simulated stratocumulus and energy fluxes over the Southeastern Pacific, and require further investigation. The well-simulated timing and outflow patterns of polluted and clean episodes demonstrate the model's ability to capture daily/synoptic scale variations of aerosol and cloud properties, and suggest that the model is suitable for studying atmospheric processes associated with pollution outflow over the ocean. The overall performance of the regional model in simulating mesoscale clouds and boundary layer properties is encouraging and suggests that reproducing gradients of aerosol and cloud droplet concentrations and coupling cloud-aerosol-radiation processes are important when simulating marine stratocumulus over the Southeast Pacific.

  19. CARES: Carbonaceous Aerosol and Radiative Effects Study Science Plan

    SciTech Connect (OSTI)

    Zaveri, RA; Shaw, WJ; Cziczo, DJ

    2010-05-27

    Carbonaceous aerosol components, which include black carbon (BC), urban primary organic aerosols (POA), biomass burning aerosols, and secondary organic aerosols (SOA) from both urban and biogenic precursors, have been previously shown to play a major role in the direct and indirect radiative forcing of climate. The primary objective of the CARES 2010 intensive field study is to investigate the evolution of carbonaceous aerosols of different types and their effects on optical and cloud formation properties.

  20. The seasonality of aerosol properties in Big Bend National Park 

    E-Print Network [OSTI]

    Allen, Christopher Lee

    2007-04-25

    ), to characterize the seasonal variability of the Big Bend regions aerosol optical properties. Mass extinction efficiencies and relative humidity scattering enhancement factors were calculated for both externally and internally mixed aerosol populations for all size...

  1. GEOPHYSICAL RESEARCH LETTERS, VOL. 26, NO. 17, PAGES 2725-2728, SEPTEMBER 1, 1999 Comparisonof AerosolOptical Depth from Four Solar

    E-Print Network [OSTI]

    Period(IOP)tostudyaerosols.Five sun-tracking radiometerswerepresentto measurethe totalcolumnaerosol opticaldepth aerosoloptical and physical propertiesusing both remote sensingand in situ techniques.Five solar tracking- channelAmesAirborneTrackingSunphotometer(AATS-6) at the SGP central facility of ARM for this IOP

  2. Marine aerosols

    E-Print Network [OSTI]

    Saltzman, ES

    2009-01-01

    proper- ties found in the marine boundary layer over theand R. E. Larson (1994), Marine boundary layer measurementsand T. Hoffmann (2002), Marine aerosol formation from

  3. ARM - Measurement - Cloud optical depth

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments?govInstrumentsnoaacrnBarrow, Alaska Outreach Home Roomparticle sizefraction ARM Data Discoveryoptical

  4. An intercomparison of lidar-derived aerosol optical properties with airborne measurements near Tokyo during ACE-Asia

    E-Print Network [OSTI]

    Clarke, Antony

    and 6 km over Sagami Bay southwest of Tokyo. The C-130 observation package included a tracking Sun extinction coefficients (sa $ 0.03 kmÀ1 ) derived from the airborne tracking Sun photometer, in situ optical

  5. CHALLENGE TO ARM AND ASP Determine aerosol radiative forcings at ARM site(s).

    E-Print Network [OSTI]

    Schwartz, Stephen E.

    aerosol optical thickness is 0.1: 3 W m-2 cooling. ~50 km Drone Radiometers AMF DIRECT DETERMINATION

  6. Developing models of aerosol representation to investigate composition, evolution, optical properties, and CCN spectra using measurements of size-resolved hygroscopicity 

    E-Print Network [OSTI]

    Gasparini, Roberto

    2006-08-16

    , size and hygroscopicity information were combined to model the aerosol as a population of multi-component particles. With this model, the aerosol hygroscopic growth factor f(RH), relating the submicron scattering at high RH to that at low RH...

  7. Aerosol indirect effects -- general circulation model intercomparison and evaluation with satellite data

    SciTech Connect (OSTI)

    Quaas, Johannes; Ming, Yi; Menon, Surabi; Takemura, Toshihiko; Wang, Minghuai; Penner, Joyce E.; Gettelman, Andrew; Lohmann, Ulrike; Bellouin, Nicolas; Boucher, Olivier; Sayer, Andrew M.; Thomas, Gareth E.; McComiskey, Allison; Feingold, Graham; Hoose, Corinna; Kristjansson, Jon Egill; Liu, Xiaohong; Balkanski, Yves; Donner, Leo J.; Ginoux, Paul A.; Stier, Philip; Feichter, Johann; Sednev, Igor; Bauer, Susanne E.; Koch, Dorothy; Grainger, Roy G.; Kirkevag, Alf; Iversen, Trond; Seland, Oyvind; Easter, Richard; Ghan, Steven J.; Rasch, Philip J.; Morrison, Hugh; Lamarque, Jean-Francois; Iacono, Michael J.; Kinne, Stefan; Schulz, Michael

    2009-04-10

    Aerosol indirect effects continue to constitute one of the most important uncertainties for anthropogenic climate perturbations. Within the international AEROCOM initiative, the representation of aerosol-cloud-radiation interactions in ten different general circulation models (GCMs) is evaluated using three satellite datasets. The focus is on stratiform liquid water clouds since most GCMs do not include ice nucleation effects, and none of the model explicitly parameterizes aerosol effects on convective clouds. We compute statistical relationships between aerosol optical depth (Ta) and various cloud and radiation quantities in a manner that is consistent between the models and the satellite data. It is found that the model-simulated influence of aerosols on cloud droplet number concentration (Nd) compares relatively well to the satellite data at least over the ocean. The relationship between Ta and liquid water path is simulated much too strongly by the models. It is shown that this is partly related to the representation of the second aerosol indirect effect in terms of autoconversion. A positive relationship between total cloud fraction (fcld) and Ta as found in the satellite data is simulated by the majority of the models, albeit less strongly than that in the satellite data in most of them. In a discussion of the hypotheses proposed in the literature to explain the satellite-derived strong fcld - Ta relationship, our results indicate that none can be identified as unique explanation. Relationships similar to the ones found in satellite data between Ta and cloud top temperature or outgoing long-wave radiation (OLR) are simulated by only a few GCMs. The GCMs that simulate a negative OLR - Ta relationship show a strong positive correlation between Ta and fcld The short-wave total aerosol radiative forcing as simulated by the GCMs is strongly influenced by the simulated anthropogenic fraction of Ta, and parameterisation assumptions such as a lower bound on Nd. Nevertheless, the strengths of the statistical relationships are good predictors for the aerosol forcings in the models. An estimate of the total short-wave aerosol forcing inferred from the combination of these predictors for the modelled forcings with the satellite-derived statistical relationships yields a global annual mean value of -1.5+-0.5 Wm-2. An alternative estimate obtained by scaling the simulated clear- and cloudy-sky forcings with estimates of anthropogenic Ta and satellite-retrieved Nd - Ta regression slopes, respectively, yields a global annual mean clear-sky (aerosol direct effect) estimate of -0.4+-0.2 Wm-2 and a cloudy-sky (aerosol indirect effect) estimate of -0.7+-0.5 Wm-2, with a total estimate of -1.2+-0.4 Wm-2.

  8. Evaluating WRF-Chem aerosol indirect effects in Southeast Pacific marine stratocumulus during VOCALS-REx

    SciTech Connect (OSTI)

    Saide P. E.; Springston S.; Spak, S. N.; Carmichael, G. R.; Mena-Carrasco, M. A.; Yang, Q.; Howell, S.; Leon, D. C.; Snider, J. R.; Bandy, A. R.; Collett, J. L.; Benedict, K. B.; de Szoeke, S. P.; Hawkins, L. N.; Allen, G.; Crawford, I.; Crosier, J.

    2012-03-29

    We evaluate a regional-scale simulation with the WRF-Chem model for the VAMOS (Variability of the American Monsoon Systems) Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx), which sampled the Southeast Pacific's persistent stratocumulus deck. Evaluation of VOCALS-REx ship-based and three aircraft observations focuses on analyzing how aerosol loading affects marine boundary layer (MBL) dynamics and cloud microphysics. We compare local time series and campaign-averaged longitudinal gradients, and highlight differences in model simulations with (W) and without (NW) wet deposition processes. The higher aerosol loadings in the NW case produce considerable changes in MBL dynamics and cloud microphysics, in accordance with the established conceptual model of aerosol indirect effects. These include increase in cloud albedo, increase in MBL and cloud heights, drizzle suppression, increase in liquid water content, and increase in cloud lifetime. Moreover, better statistical representation of aerosol mass and number concentration improves model fidelity in reproducing observed spatial and temporal variability in cloud properties, including top and base height, droplet concentration, water content, rain rate, optical depth (COD) and liquid water path (LWP). Together, these help to quantify confidence in WRF-Chem's modeled aerosol-cloud interactions, especially in the activation parameterization, while identifying structural and parametric uncertainties including: irreversibility in rain wet removal; overestimation of marine DMS and sea salt emissions, and accelerated aqueous sulfate conversion. Our findings suggest that WRF-Chem simulates marine cloud-aerosol interactions at a level sufficient for applications in forecasting weather and air quality and studying aerosol climate forcing, and may do so with the reliability required for policy analysis.

  9. Evaluating WRF-Chem aerosol indirect effects in Southeast Pacific marine stratocumulus during VOCALS-REx

    SciTech Connect (OSTI)

    Saide, Pablo; Spak, S. N.; Carmichael, Gregory; Mena-Carrasco, M. A.; Yang, Qing; Howell, S. G.; Leon, Dolislager; Snider, Jefferson R.; Bandy, Alan R.; Collett, Jeffrey L.; Benedict, K. B.; de Szoeke, S.; Hawkins, Lisa; Allen, Grant; Crawford, I.; Crosier, J.; Springston, S. R.

    2012-03-30

    We evaluate a regional-scale simulation with the WRF-Chem model for the VAMOS (Variability of the American Monsoon Systems) Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx), which sampled the Southeast Pacific's persistent stratocumulus deck. Evaluation of VOCALS-REx ship-based and aircraft observations focuses on analyzing how aerosol loading affects marine boundary layer (MBL) dynamics and cloud microphysics. We compare local time series and campaign averaged longitudinal gradients, and highlight differences in model simulations with (W) and without wet (NW) deposition processes. The higher aerosol loadings in the NW case produce considerable changes in MBL dynamics and cloud microphysics, in accordance with the established conceptual model of aerosol indirect effects. These include increase in cloud albedo, increase in MBL and cloud heights, drizzle suppression, increase in liquid water content, and increase in cloud lifetime. Moreover, better statistical representation of aerosol mass and number concentration improves model fidelity in reproducing observed spatial and temporal variability in cloud properties, including top and base height, droplet concentration, water content, rain rate, optical depth (COD) and liquid water path (LWP). Together, these help to quantify confidence in WRF-Chem's modeled aerosol-cloud interactions, while identifying structural and parametric uncertainties including: irreversibility in rain wet removal; overestimation of marine DMS and sea salt emissions and accelerated aqueous sulfate conversion. Our findings suggest that WRF-Chem simulates marine cloud-aerosol interactions at a level sufficient for applications in forecasting weather and air quality and studying aerosol climate forcing, including the reliability required for policy analysis and geo-engineering applications.

  10. Use of the ARM Measurements of Spectral Zenith Radiance for Better Understanding of 3D Cloud-Radiation Processes & Aerosol-Cloud Interaction

    SciTech Connect (OSTI)

    Chiu, Jui-Yuan Christine [University of Reading] [University of Reading

    2014-04-10

    This project focuses on cloud-radiation processes in a general three-dimensional cloud situation, with particular emphasis on cloud optical depth and effective particle size. The proposal has two main parts. Part one exploits the large number of new wavelengths offered by the Atmospheric Radiation Measurement (ARM) zenith-pointing ShortWave Spectrometer (SWS), to develop better retrievals not only of cloud optical depth but also of cloud particle size. We also take advantage of the SWS’ high sampling resolution to study the “twilight zone” around clouds where strong aerosol-cloud interactions are taking place. Part two involves continuing our cloud optical depth and cloud fraction retrieval research with ARM’s 2-channel narrow vield-of-view radiometer and sunphotometer instrument by, first, analyzing its data from the ARM Mobile Facility deployments, and second, making our algorithms part of ARM’s operational data processing.

  11. Use of the ARM Measurement of Spectral Zenith Radiance For Better Understanding Of 3D Cloud-Radiation Processes and Aerosol-Cloud Interaction

    SciTech Connect (OSTI)

    D. Jui-Yuan Chiu

    2010-10-19

    Our proposal focuses on cloud-radiation processes in a general 3D cloud situation, with particular emphasis on cloud optical depth and effective particle size. We also focus on zenith radiance measurements, both active and passive. The proposal has three main parts. Part One exploits the �¢����solar-background�¢��� mode of ARM lidars to allow them to retrieve cloud optical depth not just for thin clouds but for all clouds. This also enables the study of aerosol cloud interactions with a single instrument. Part Two exploits the large number of new wavelengths offered by ARM�¢����s zenith-pointing ShortWave Spectrometer (SWS), especially during CLASIC, to develop better retrievals not only of cloud optical depth but also of cloud particle size. We also propose to take advantage of the SWS�¢���� 1 Hz sampling to study the �¢����twilight zone�¢��� around clouds where strong aerosol-cloud interactions are taking place. Part Three involves continuing our cloud optical depth and cloud fraction retrieval research with ARM�¢����s 2NFOV instrument by, first, analyzing its data from the AMF-COPS/CLOWD deployment, and second, making our algorithms part of ARM�¢����s operational data processing.

  12. Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds

    SciTech Connect (OSTI)

    Richard A. Ferrare; David D. Turner

    2011-09-01

    Project goals: (1) Use the routine surface and airborne measurements at the ARM SGP site, and the routine surface measurements at the NSA site, to continue our evaluations of model aerosol simulations; (2) Determine the degree to which the Raman lidar measurements of water vapor and aerosol scattering and extinction can be used to remotely characterize the aerosol humidification factor; (3) Use the high temporal resolution CARL data to examine how aerosol properties vary near clouds; and (4) Use the high temporal resolution CARL and Atmospheric Emitted Radiance Interferometer (AERI) data to quantify entrainment in optically thin continental cumulus clouds.

  13. Multi-frequency optical-depth maps and the case for free-free absorption in two compact symmetric radio sources: The CSO candidate J1324 + 4048 and the CSO J0029 + 3457

    SciTech Connect (OSTI)

    Marr, J. M.; Read, J.; Morris, A. O.; Perry, T. M.; Taylor, G. B.

    2014-01-10

    We obtained dual-polarization very long baseline interferometry observations at six frequencies of the compact symmetric object J0029 + 3457 and the compact symmetric object candidate J1324 + 4048. By comparing the three lower-frequency maps with extrapolations of the high-frequency maps, we produced maps of the optical depth as a function of frequency. The morphology of the optical-depth maps of J1324 + 4048 is strikingly smooth, suggestive of a foreground screen of absorbing gas. The spectra at the intensity peaks fit a simple free-free absorption (FFA) model, with ?{sub ?}{sup 2}?2, better than a simple synchrotron self-absorption model, in which ?{sub ?}{sup 2}?3.5--5.5. We conclude that the case for FFA in J1324 + 4048 is strong. The optical-depth maps of J0029 + 3457 exhibit structure, but the morphology does not correlate with that in the intensity maps. The fit of the spectra at the peaks to a simple FFA model yields ?{sub ?}{sup 2}?1, but because the turnover is gradual, the fit is relatively insensitive to the input parameters. We find that FFA by a thin amount of gas in J0029 + 3457 is likely but not definitive. One compact feature in J0029 + 3457 has an inverted spectrum even at the highest frequencies. We infer this to be the location of the core and estimate an upper limit to the magnetic field of order 3 Gauss at a radius of order 1 pc. In comparison with maps from observations at earlier epochs, no apparent growth in either J1324 + 4048 or J0029 + 3457 is apparent, with upper limits of 0.03 and 0.02 mas yr{sup –1}, corresponding to maximum linear separation speeds of 0.6c and 0.4c.

  14. Cloud Scavenging Effects on Aerosol Radiative and Cloud-nucleating Properties - Final Technical Report

    SciTech Connect (OSTI)

    Ogren, John A.; Sheridan, Patrick S.; Andrews, Elisabeth

    2009-03-05

    The optical properties of aerosol particles are the controlling factors in determining direct aerosol radiative forcing. These optical properties depend on the chemical composition and size distribution of the aerosol particles, which can change due to various processes during the particles’ lifetime in the atmosphere. Over the course of this project we have studied how cloud processing of atmospheric aerosol changes the aerosol optical properties. A counterflow virtual impactor was used to separate cloud drops from interstitial aerosol and parallel aerosol systems were used to measure the optical properties of the interstitial and cloud-scavenged aerosol. Specifically, aerosol light scattering, back-scattering and absorption were measured and used to derive radiatively significant parameters such as aerosol single scattering albedo and backscatter fraction for cloud-scavenged and interstitial aerosol. This data allows us to demonstrate that the radiative properties of cloud-processed aerosol can be quite different than pre-cloud aerosol. These differences can be used to improve the parameterization of aerosol forcing in climate models.

  15. Climatological simulations of ozone and atmospheric aerosols in the Greater Cairo region

    SciTech Connect (OSTI)

    Steiner, A. L.; Tawfik, A. B.; Shalaby, A.; Zakey, A. S.; Abdel Wahab, M. M.; Salah, Z.; Solmon, F.; Sillman, S.; Zaveri, Rahul A.

    2014-04-16

    An integrated chemistry-climate model (RegCM4-CHEM) simulates present-day climate, ozone and tropospheric aerosols over Egypt with a focus on Greater Cairo (GC) region. The densley populated GC region is known for its severe air quality issues driven by high levels of anthropogenic pollution in conjuction with natural sources such as dust and agricultural burning events. We find that current global emission inventories underestimate key pollutants such as nitrogen oxides and anthropogenic aerosol species. In the GC region, average-ground-based NO2 observations of 40-60 ppb are substantially higher than modeled estimates (5-10 ppb), likely due to model grid resolution, improper boundary layer representation, and poor emissions inventories. Observed ozone concentrations range from 35 ppb (winter) to 80 ppb (summer). The model reproduces the seasonal cycle fairly well, but modeled summer ozone is understimated by approximately 15 ppb and exhibits little interannual variability. For aerosols, springtime dust events dominate the seasonal aerosol cycle. The chemistry-climate model captures the springtime peak aerosol optical depth (AOD) of 0.7-1 but is slightly greater than satellite-derived AOD. Observed AOD decreases in the summer and increases again in the fall due to agricultural burning events in the Nile Delta, yet the model underestimates this fall observed AOD peak, as standard emissions inventories underestimate this burning and the resulting aerosol emissions. Our comparison of modeled gas and particulate phase atmospheric chemistry in the GC region indicates that improved emissions inventories of mobile sources and other anthropogenic activities are needed to improve air quality simulations in this region.

  16. Evaluating Clouds, Aerosols, and their Interactions in Three Global Climate Models using COSP and Satellite Observations

    SciTech Connect (OSTI)

    Ban-Weiss, George; Jin, Ling; Bauer, S.; Bennartz, Ralph; Liu, Xiaohong; Zhang, Kai; Ming, Yi; Guo, Huan; Jiang, Jonathan

    2014-09-23

    Accurately representing aerosol-cloud interactions in global climate models is challenging. As parameterizations evolve, it is important to evaluate their performance with appropriate use of observations. In this work we compare aerosols, clouds, and their interactions in three climate models (AM3, CAM5, ModelE) to MODIS satellite observations. Modeled cloud properties were diagnosed using the CFMIP Observations Simulator Package (COSP). Cloud droplet number concentrations (N) were derived using the same algorithm for both satellite-simulated model values and observations. We find that aerosol optical depth tau simulated by models is similar to observations. For N, AM3 and CAM5 capture the observed spatial pattern of higher values in near-coast versus remote ocean regions, though modeled values in general are higher than observed. In contrast, ModelE simulates lower N in most near-coast versus remote regions. Aerosol- cloud interactions were computed as the sensitivity of N to tau for marine liquid clouds off the coasts of South Africa and Eastern Asia where aerosol pollution varies in time. AM3 and CAM5 are in most cases more sensitive than observations, while the sensitivity for ModelE is statistically insignificant. This widely used sensitivity could be subject to misinterpretation due to the confounding influence of meteorology on both aerosols and clouds. A simple framework for assessing the N – tau sensitivity at constant meteorology illustrates that observed sensitivity can change from positive to statistically insignificant when including the confounding influence of relative humidity. Satellite simulated values of N were compared to standard model output and found to be higher with a bias of 83 cm-3.

  17. Radiative and thermodynamic responses to aerosol extinction profiles during the pre-monsoon month over South Asia

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Feng, Y.; Kotamarthi, V. R.; Coulter, R.; Zhao, C.; Cadeddu, M.

    2015-01-01

    Aerosol radiative effects and thermodynamic responses over South Asia are examined with a version of the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) for March 2012. Model results of Aerosol Optical Depth (AOD) and extinction profiles are analyzed and compared to satellite retrievals and two ground-based lidars located in the northern India. The WRF-Chem model is found to underestimate the AOD during the simulated pre-monsoon month and about 83 % of the model low-bias is due to aerosol extinctions below ~2 km. Doubling the calculated aerosol extinctions below 850 hPa generates much better agreement with the observed AODmore »and extinction profiles averaged over South Asia. To separate the effect of absorption and scattering properties, two runs were conducted: in one run (Case I), the calculated scattering and absorption coefficients were increased proportionally, while in the second run (Case II) only the calculated aerosol scattering coefficient was increased. With the same AOD and extinction profiles, the two runs produce significantly different radiative effects over land and oceans. On the regional mean basis, Case I generates 48 % more heating in the atmosphere and 21 % more dimming at the surface than Case II. Case I also produces stronger cooling responses over the land from the longwave radiation adjustment and boundary layer mixing. These rapid adjustments offset the stronger radiative heating in Case I and lead to an overall lower-troposphere cooling up to -0.7 K day?1, which is smaller than that in Case II. Over the ocean, direct radiative effects dominate the heating rate changes in the lower atmosphere lacking such surface and lower atmosphere adjustments due to fixed sea surface temperature, and the strongest atmospheric warming is obtained in Case I. Consequently, atmospheric dynamics (boundary layer heights and meridional circulation) and thermodynamic processes (water vapor and cloudiness) are shown to respond differently between Case I and Case II underlying the importance of determining the exact portion of scattering or absorbing aerosols that lead to the underestimation of aerosol optical depth in the model. In addition, the model results suggest that both direct radiative effect and rapid thermodynamic responses need to be quantified for understanding aerosol radiative impacts.« less

  18. Radiative and thermodynamic responses to aerosol extinction profiles during the pre-monsoon month over South Asia

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Feng, Y.; Kotamarthi, V. R.; Coulter, R.; Zhao, C.; Cadeddu, M.

    2015-06-19

    Aerosol radiative effects and thermodynamic responses over South Asia are examined with a version of the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) for March 2012. Model results of Aerosol Optical Depth (AOD) and extinction profiles are analyzed and compared to satellite retrievals and two ground-based lidars located in the northern India. The WRF-Chem model is found to underestimate the AOD during the simulated pre-monsoon month and about 83 % of the model low-bias is due to aerosol extinctions below ~2 km. Doubling the calculated aerosol extinctions below 850 hPa generates much better agreement with the observed AODmore »and extinction profiles averaged over South Asia. To separate the effect of absorption and scattering properties, two runs were conducted: in one run (Case I), the calculated scattering and absorption coefficients were increased proportionally, while in the second run (Case II) only the calculated aerosol scattering coefficient was increased. With the same AOD and extinction profiles, the two runs produce significantly different radiative effects over land and oceans. On the regional mean basis, Case I generates 48 % more heating in the atmosphere and 21 % more dimming at the surface than Case II. Case I also produces stronger cooling responses over the land from the longwave radiation adjustment and boundary layer mixing. These rapid adjustments offset the stronger radiative heating in Case I and lead to an overall lower-troposphere cooling up to -0.7 K day?1, which is smaller than that in Case II. Over the ocean, direct radiative effects dominate the heating rate changes in the lower atmosphere lacking such surface and lower atmosphere adjustments due to fixed sea surface temperature, and the strongest atmospheric warming is obtained in Case I. Consequently, atmospheric dynamics (boundary layer heights and meridional circulation) and thermodynamic processes (water vapor and cloudiness) are shown to respond differently between Case I and Case II underlying the importance of determining the exact portion of scattering or absorbing aerosols that lead to the underestimation of aerosol optical depth in the model. In addition, the model results suggest that both direct radiative effect and rapid thermodynamic responses need to be quantified for understanding aerosol radiative impacts.« less

  19. ARM - Measurement - Aerosol optical properties

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments?govInstrumentsnoaacrnBarrow, Alaska Outreach Home Room NewsgovMeasurementsAdvectiveeffectiveproperties

  20. Aerosol indirect effects ? general circulation model intercomparison and evaluation with satellite data

    SciTech Connect (OSTI)

    Quaas, Johannes; Ming, Yi; Menon, Surabi; Takemura, Toshihiko; Wang, Minghuai; Penner, Joyce E.; Gettelman, Andrew; Lohmann, Ulrike; Bellouin, Nicolas; Boucher, Olivier; Sayer, Andrew M.; Thomas, Gareth E.; McComiskey, Allison; Feingold, Graham; Hoose, Corinna; Kristansson, Jon Egill; Liu, Xiaohong; Balkanski, Yves; Donner, Leo J.; Ginoux, Paul A.; Stier, Philip; Grandey, Benjamin; Feichter, Johann; Sednev, Igor; Bauer, Susanne E.; Koch, Dorothy; Grainger, Roy G.; Kirkevag, Alf; Iversen, Trond; Seland, Oyvind; Easter, Richard; Ghan, Steven J.; Rasch, Philip J.; Morrison, Hugh; Lamarque, Jean-Francois; Iacono, Michael J.; Kinne, Stefan; Schulz, Michael

    2010-03-12

    Aerosol indirect effects continue to constitute one of the most important uncertainties for anthropogenic climate perturbations. Within the international AEROCOM initiative, the representation of aerosol-cloud-radiation interactions in ten different general circulation models (GCMs) is evaluated using three satellite datasets. The focus is on stratiform liquid water clouds since most GCMs do not include ice nucleation effects, and none of the model explicitly parameterises aerosol effects on convective clouds. We compute statistical relationships between aerosol optical depth ({tau}{sub a}) and various cloud and radiation quantities in a manner that is consistent between the models and the satellite data. It is found that the model-simulated influence of aerosols on cloud droplet number concentration (N{sub d}) compares relatively well to the satellite data at least over the ocean. The relationship between {tau}{sub a} and liquid water path is simulated much too strongly by the models. This suggests that the implementation of the second aerosol indirect effect mainly in terms of an autoconversion parameterisation has to be revisited in the GCMs. A positive relationship between total cloud fraction (f{sub cld}) and {tau}{sub a} as found in the satellite data is simulated by the majority of the models, albeit less strongly than that in the satellite data in most of them. In a discussion of the hypotheses proposed in the literature to explain the satellite-derived strong f{sub cld} - {tau}{sub a} relationship, our results indicate that none can be identified as a unique explanation. Relationships similar to the ones found in satellite data between {tau}{sub a} and cloud top temperature or outgoing long-wave radiation (OLR) are simulated by only a few GCMs. The GCMs that simulate a negative OLR - {tau}{sub a} relationship show a strong positive correlation between {tau}{sub a} and f{sub cld} The short-wave total aerosol radiative forcing as simulated by the GCMs is strongly influenced by the simulated anthropogenic fraction of {tau}{sub a}, and parameterization assumptions such as a lower bound on N{sub d}. Nevertheless, the strengths of the statistical relationships are good predictors for the aerosol forcings in the models. An estimate of the total short-wave aerosol forcing inferred from the combination of these predictors for the modelled forcings with the satellite-derived statistical relationships yields a global annual mean value of -1.5 {+-} 0.5 Wm{sup -2}. In an alternative approach, the radiative flux perturbation due to anthropogenic aerosols can be broken down into a component over the cloud-free portion of the globe (approximately the aerosol direct effect) and a component over the cloudy portion of the globe (approximately the aerosol indirect effect). An estimate obtained by scaling these simulated clear- and cloudy-sky forcings with estimates of anthropogenic {tau}{sub a} and satellite-retrieved Nd - {tau}{sub a} regression slopes, respectively, yields a global, annual-mean aerosol direct effect estimate of -0.4 {+-} 0.2 Wm{sup -2} and a cloudy-sky (aerosol indirect effect) estimate of -0.7 {+-} 0.5 Wm{sup -2}, with a total estimate of -1.2 {+-} 0.4 Wm{sup -2}.

  1. Effects of sulfate aerosol on the central Pennsylvania surface shortwave radiation budget. Master's thesis

    SciTech Connect (OSTI)

    Guimond, P.W.

    1994-12-01

    Surface radiation measurements are taken simultaneously with measurements of meteorological variables including temperature, pressure, relative humidity, and visibility to evaluate the impact of sulfate haze on the surface radiation budget. A relationship is sought between flux losses due only to aerosol and relative humidity, visibility or both, with the goal of facilitating parameterization of sulfate hazes by climate modelers. At the same time, a rotating shadowband radiometer (RSR) is compared with a more costly sun photometer to determine the feasibility of substituting the former for the latter in future research. It is found that depletion of surface radiation due to aerosol is typically ten to twenty percent of initial insolation, and that the losses can be correlated with zenith angle, relative humidity and optical depth. In the case of flux loss as a function of optical depth, the two are related in a nearly linear fashion. It is also discovered that the RSR has a predictable error owing to a wider field of view than the sun photometer, and can be used as a replacement for the former by correcting for the error.

  2. GLOBAL AEROSOL EFFECT RETRIEVAL FROM PASSIVE HYPERSPECTRAL MEASUREMENTS

    E-Print Network [OSTI]

    Graaf, Martin de

    that can be detected using UV reflectance measurements. Since the aerosol extinction optical thickness any instrument, or a combination of instruments, that measures UV, visible and SWIR reflectancesGLOBAL AEROSOL EFFECT RETRIEVAL FROM PASSIVE HYPERSPECTRAL MEASUREMENTS M. de Graaf1,2 , L. G

  3. Intercomparison and evaluation of global aerosol microphysical properties among AeroCom models of a range of complexity

    E-Print Network [OSTI]

    Ridley, David Andrew

    Many of the next generation of global climate models will include aerosol schemes which explicitly simulate the microphysical processes that determine the particle size distribution. These models enable aerosol optical ...

  4. Aerosol remote sensing in polar regions

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Tomasi, Claudio; Kokhanovsky, Alexander A.; Lupi, Angelo; Ritter, Christoph; Smirnov, Alexander; O'Neill, Norman T.; Stone, Robert S.; Holben, Brent N.; Nyeki, Stephan; Wehrli, Christoph; et al

    2015-01-01

    Multi-year sets of ground-based sun-photometer measurements conducted at 12 Arctic sites and 9 Antarctic sites were examined to determine daily mean values of aerosol optical thickness ?(?) at visible and near-infrared wavelengths, from which best-fit values of Ångström's exponent ? were calculated. Analysing these data, the monthly mean values of ?(0.50 ?m) and ? and the relative frequency histograms of the daily mean values of both parameters were determined for winter–spring and summer–autumn in the Arctic and for austral summer in Antarctica. The Arctic and Antarctic covariance plots of the seasonal median values of ? versus ?(0.50 ?m) showed: (i)more »a considerable increase in ?(0.50 ?m) for the Arctic aerosol from summer to winter–spring, without marked changes in ?; and (ii) a marked increase in ?(0.50 ?m) passing from the Antarctic Plateau to coastal sites, whereas ? decreased considerably due to the larger fraction of sea-salt aerosol. Good agreement was found when comparing ground-based sun-photometer measurements of ?(?) and ? at Arctic and Antarctic coastal sites with Microtops measurements conducted during numerous AERONET/MAN cruises from 2006 to 2013 in three Arctic Ocean sectors and in coastal and off-shore regions of the Southern Atlantic, Pacific, and Indian Oceans, and the Antarctic Peninsula. Lidar measurements were also examined to characterise vertical profiles of the aerosol backscattering coefficient measured throughout the year at Ny-Ålesund. Satellite-based MODIS, MISR, and AATSR retrievals of ?(?) over large parts of the oceanic polar regions during spring and summer were in close agreement with ship-borne and coastal ground-based sun-photometer measurements. An overview of the chemical composition of mode particles is also presented, based on in-situ measurements at Arctic and Antarctic sites. Fourteen log-normal aerosol number size-distributions were defined to represent the average features of nuclei, accumulation and coarse mode particles for Arctic haze, summer background aerosol, Asian dust and boreal forest fire smoke, and for various background austral summer aerosol types at coastal and high-altitude Antarctic sites. The main columnar aerosol optical characteristics were determined for all 14 particle modes, based on in-situ measurements of the scattering and absorption coefficients. Diurnally averaged direct aerosol-induced radiative forcing and efficiency were calculated for a set of multimodal aerosol extinction models, using various Bidirectional Reflectance Distribution Function models over vegetation-covered, oceanic and snow-covered surfaces. These gave a reliable measure of the pronounced effects of aerosols on the radiation balance of the surface–atmosphere system over polar regions.« less

  5. Aerosol remote sensing in polar regions

    SciTech Connect (OSTI)

    Tomasi, Claudio; Kokhanovsky, Alexander A.; Lupi, Angelo; Ritter, Christoph; Smirnov, Alexander; O'Neill, Norman T.; Stone, Robert S.; Holben, Brent N.; Nyeki, Stephan; Mazzola, Mauro; Lanconelli, Christian; Vitale, Vito; Stebel, Kerstin; Aaltonen, Veijo; de Leeuw, Gerrit; Rodriguez, Edith; Herber, Andreas B.; Radionov, Vladimir F.; Zielinski, Tymon; Petelski, Tomasz; Sakerin, Sergey M.; Kabanov, Dmitry M.; Xue, Yong; Mei, Linlu; Istomina, Larysa; Wagener, Richard; McArthur, Bruce; Sobolewski, Piotr S.; Kivi, Rigel; Courcoux, Yann; Larouche, Pierre; Broccardo, Stephen; Piketh, Stuart J.

    2015-01-01

    Multi-year sets of ground-based sun-photometer measurements conducted at 12 Arctic sites and 9 Antarctic sites were examined to determine daily mean values of aerosol optical thickness ?(?) at visible and near-infrared wavelengths, from which best-fit values of Ångström's exponent ? were calculated. Analysing these data, the monthly mean values of ?(0.50 ?m) and ? and the relative frequency histograms of the daily mean values of both parameters were determined for winter–spring and summer–autumn in the Arctic and for austral summer in Antarctica. The Arctic and Antarctic covariance plots of the seasonal median values of ? versus ?(0.50 ?m) showed: (i) a considerable increase in ?(0.50 ?m) for the Arctic aerosol from summer to winter–spring, without marked changes in ?; and (ii) a marked increase in ?(0.50 ?m) passing from the Antarctic Plateau to coastal sites, whereas ? decreased considerably due to the larger fraction of sea-salt aerosol. Good agreement was found when comparing ground-based sun-photometer measurements of ?(?) and ? at Arctic and Antarctic coastal sites with Microtops measurements conducted during numerous AERONET/MAN cruises from 2006 to 2013 in three Arctic Ocean sectors and in coastal and off-shore regions of the Southern Atlantic, Pacific, and Indian Oceans, and the Antarctic Peninsula. Lidar measurements were also examined to characterise vertical profiles of the aerosol backscattering coefficient measured throughout the year at Ny-Ålesund. Satellite-based MODIS, MISR, and AATSR retrievals of ?(?) over large parts of the oceanic polar regions during spring and summer were in close agreement with ship-borne and coastal ground-based sun-photometer measurements. An overview of the chemical composition of mode particles is also presented, based on in-situ measurements at Arctic and Antarctic sites. Fourteen log-normal aerosol number size-distributions were defined to represent the average features of nuclei, accumulation and coarse mode particles for Arctic haze, summer background aerosol, Asian dust and boreal forest fire smoke, and for various background austral summer aerosol types at coastal and high-altitude Antarctic sites. The main columnar aerosol optical characteristics were determined for all 14 particle modes, based on in-situ measurements of the scattering and absorption coefficients. Diurnally averaged direct aerosol-induced radiative forcing and efficiency were calculated for a set of multimodal aerosol extinction models, using various Bidirectional Reflectance Distribution Function models over vegetation-covered, oceanic and snow-covered surfaces. These gave a reliable measure of the pronounced effects of aerosols on the radiation balance of the surface–atmosphere system over polar regions.

  6. Solid aerosol generator

    DOE Patents [OSTI]

    Prescott, D.S.; Schober, R.K.; Beller, J.

    1992-03-17

    An improved solid aerosol generator used to produce a gas borne stream of dry, solid particles of predetermined size and concentration is disclosed. The improved solid aerosol generator nebulizes a feed solution of known concentration with a flow of preheated gas and dries the resultant wet heated aerosol in a grounded, conical heating chamber, achieving high recovery and flow rates. 2 figs.

  7. Improved solid aerosol generator

    DOE Patents [OSTI]

    Prescott, D.S.; Schober, R.K.; Beller, J.

    1988-07-19

    An improved solid aerosol generator used to produce a gas borne stream of dry, solid particles of predetermined size and concentration. The improved solid aerosol generator nebulizes a feed solution of known concentration with a flow of preheated gas and dries the resultant wet heated aerosol in a grounded, conical heating chamber, achieving high recovery and flow rates. 2 figs.

  8. Experiments related to the resuspension of aerosols during hydrogen burns

    SciTech Connect (OSTI)

    Nelson, L.S.; Guay, K.P.

    1987-01-01

    We have performed seven ''add-on'' experiments in two large combustion facilities to investigate the capability of hydrogen burns to remove simulated structural and fission product aerosols previously deposited on small metal discs that have surfaces prototypical of those found in nuclear reactor containments. Our results suggest that hydrogen combustion provides an especially effective mechanism for removal (and, presumably, resuspension) of sedimented aerosols produced in a hypothetical nuclear reactor core-degradation or core-melting accident. The presence of condensing steam does not seem to assure adhesion of sedimented aerosols during hydrogen burns. Differences are exhibited between different surfaces as well as between types of aerosol. In-depth studies will be required to assess the impact exposure of sedimented aerosols to hydrogen burns might have on the radiological source term.

  9. Optical properties of boreal forest fire smoke derived from Sun photometry

    E-Print Network [OSTI]

    Zeng, Ning

    Optical properties of boreal forest fire smoke derived from Sun photometry N. T. O'Neill,1 T. F 2001; published 13 June 2002. [1] Aerosol optical properties derived from Sun photometry were: Aerosols (0305); KEYWORDS: aerosols, forest fire smoke, Sun photometry, optics 1. Introduction [2] Smoke

  10. Assessment of multi-decadal WRF-CMAQ simulations for understanding direct aerosol effects on radiation "brightening" in the United States

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gan, C.-M.; Pleim, J.; Mathur, R.; Hogrefe, C.; Long, C. N.; Xing, J.; Wong, D.; Gilliam, R.; Wei, C.

    2015-07-01

    Multi-decadal simulations with the coupled WRF-CMAQ model have been conducted to systematically investigate the changes in anthropogenic emissions of SO2 and NOx over the past 21 years (1990–2010) across the United States (US), their impacts on anthropogenic aerosol loading over North America, and subsequent impacts on regional radiation budgets. In particular, this study attempts to determine the consequences of the changes in tropospheric aerosol burden arising from substantial reductions in emissions of SO2 and NOx associated with control measures under the Clean Air Act (CAA) especially on trends in solar radiation. Extensive analyses conducted by Gan et al. (2014) utilizingmore »observations (e.g. SURFRAD, CASTNET, IMPROVE and ARM) over the past 16 years (1995–2010) indicate a shortwave (SW) radiation (both all-sky and clear-sky) "brightening" in the US. The relationship of the radiation brightening trend with decreases in the aerosol burden is less apparent in the western US. One of the main reasons for this is that the emission controls under the CAA were aimed primarily at reducing pollutants in areas violating national air quality standards, most of which were located in the eastern US while the relatively less populated areas in the western US were less polluted at the beginning of this study period. Comparisons of model results with observations of aerosol optical depth (AOD), aerosol concentration, and radiation demonstrate that the coupled WRF-CMAQ model is capable of replicating the trends well even through it tends to underestimate the AOD. In particular, the sulfate concentration predictions were well matched with the observations. The discrenpancies found in the clear-sky diffuse SW radiation are likely due to several factors such as potential increase of ice particles associated with increasing air traffic, the definition of "clear-sky" in the radiation retrieval methodology and aerosol semi-direct and/or indirect effects which cannot be readily isolated from the observed data.« less

  11. Development and Characterization of a Thermodenuder for Aerosol Volatility Measurements

    SciTech Connect (OSTI)

    Dr. Timothy Onasch

    2009-09-09

    This SBIR Phase I project addressed the critical need for improved characterization of carbonaceous aerosol species in the atmosphere. The proposed work focused on the development of a thermodenuder (TD) system capable of systematically measuring volatility profiles of primary and secondary organic aerosol species and providing insight into the effects of absorbing and nonabsorbing organic coatings on particle absorption properties. This work provided the fundamental framework for the generation of essential information needed for improved predictions of ambient aerosol loadings and radiative properties by atmospheric chemistry models. As part of this work, Aerodyne Research, Inc. (ARI) continued to develop and test, with the final objective of commercialization, an improved thermodenuder system that can be used in series with any aerosol instrument or suite of instruments (e.g., aerosol mass spectrometers-AMS, scanning mobility particle sizers-SMPS, photoacoustic absorption spectrometers-PAS, etc.) to obtain aerosol chemical, physical, and optical properties as a function of particle volatility. In particular, we provided the proof of concept for the direct coupling of our improved TD design with a full microphysical model to obtain volatility profiles for different organic aerosol components and to allow for meaningful comparisons between different TD-derived aerosol measurements. In a TD, particles are passed through a heated zone and a denuding (activated charcoal) zone to remove semi-volatile material. Changes in particle size, number concentration, optical absorption, and chemical composition are subsequently detected with aerosol instrumentation. The aerosol volatility profiles provided by the TD will strengthen organic aerosol emission inventories, provide further insight into secondary aerosol formation mechanisms, and provide an important measure of particle absorption (including brown carbon contributions and identification, and absorption enhancements due to coatings on soot particles). The successfully completed Phase I project included construction of a prototype design for the TD with detailed physical modeling, testing with laboratory and ambient aerosol particles, and the initiation of a detailed microphysical model of the aerosol particles passing through the TD to extract vapor pressure distributions. The objective of the microphysical model is to derive vapor pressure distributions (i.e. vapor pressure ranges, including single chemical compounds, mixtures of known compounds, and complex ‘real-world’ aerosols, such as SOA, and soot particles with absorbing and nonabsorbing coatings) from TD measurements of changes in particle size, mass, and chemical composition for known TD temperatures and flow rates (i.e. residence times). The proposed Phase II project was designed to optimize several TD systems for different instrument applications and to combine the hardware and modeling into a robust package for commercial sales.

  12. Climate implications of carbonaceous aerosols: An aerosol microphysical study using the GISS/MATRIX climate model

    SciTech Connect (OSTI)

    Bauer, Susanne E.; Menon, Surabi; Koch, Dorothy; Bond, Tami; Tsigaridis, Kostas

    2010-04-09

    Recently, attention has been drawn towards black carbon aerosols as a likely short-term climate warming mitigation candidate. However the global and regional impacts of the direct, cloud-indirect and semi-direct forcing effects are highly uncertain, due to the complex nature of aerosol evolution and its climate interactions. Black carbon is directly released as particle into the atmosphere, but then interacts with other gases and particles through condensation and coagulation processes leading to further aerosol growth, aging and internal mixing. A detailed aerosol microphysical scheme, MATRIX, embedded within the global GISS modelE includes the above processes that determine the lifecycle and climate impact of aerosols. This study presents a quantitative assessment of the impact of microphysical processes involving black carbon, such as emission size distributions and optical properties on aerosol cloud activation and radiative forcing. Our best estimate for net direct and indirect aerosol radiative forcing change is -0.56 W/m{sup 2} between 1750 and 2000. However, the direct and indirect aerosol effects are very sensitive to the black and organic carbon size distribution and consequential mixing state. The net radiative forcing change can vary between -0.32 to -0.75 W/m{sup 2} depending on these carbonaceous particle properties. Assuming that sulfates, nitrates and secondary organics form a coating shell around a black carbon core, rather than forming a uniformly mixed particles, changes the overall net radiative forcing from a negative to a positive number. Black carbon mitigation scenarios showed generally a benefit when mainly black carbon sources such as diesel emissions are reduced, reducing organic and black carbon sources such as bio-fuels, does not lead to reduced warming.

  13. Computation of Texture and Stereoscopic Depth in Humans

    E-Print Network [OSTI]

    Fahle, Manfred

    1989-10-01

    The computation of texture and of stereoscopic depth is limited by a number of factors in the design of the optical front-end and subsequent processing stages in humans and machines. A number of limiting factors in ...

  14. Source Attribution of Light Absorbing Aerosol in Arctic Snow

    E-Print Network [OSTI]

    Source Attribution of Light Absorbing Aerosol in Arctic Snow (Preliminary analysis of 2008 Biomass/poll. Factor: all data Pollution factor: depth data #12;2009 Data set for receptor modeling with limited analytes Factor 1: biomass Factor 2: pollution Factor 3: marine Factor 4: biomass #12;Factor

  15. Effect of Aerosol Humidification on the Column Aerosol Optical Thickness

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submitKansas Nuclear Profile 2010MesoscopyStaff »Vehicle automation is aover the ARM

  16. Modeling aerosols and their interactions with shallow cumuli during the 2007 CHAPS field study

    SciTech Connect (OSTI)

    Shrivastava, ManishKumar B.; Berg, Larry K.; Fast, Jerome D.; Easter, Richard C.; Laskin, Alexander; Chapman, Elaine G.; Gustafson, William I.; Liu, Ying; Berkowitz, Carl M.

    2013-02-07

    The Weather Research and Forecasting model coupled with chemistry (WRF-Chem) is used to simulate relationships between aerosols and clouds in the vicinity of Oklahoma City during the June 2007 Cumulus Humilis Aerosol Processing Study (CHAPS). The regional scale simulation completed using 2 km horizontal grid spacing evaluates four important relationships between aerosols and shallow cumulus clouds observed during CHAPS. First, the model reproduces the trends of higher nitrate volume fractions in cloud droplet residuals compared to interstitial non-activated aerosols, as measured using the Aerosol Mass Spectrometer. Comparing simulations with cloud chemistry turned on and off, we show that nitric acid vapor uptake by cloud droplets explains the higher nitrate content of cloud droplet residuals. Second, as documented using an offline code, both aerosol water and other inorganics (OIN), which are related to dust and crustal emissions, significantly affect predicted aerosol optical properties. Reducing the OIN content of wet aerosols by 50% significantly improves agreement of model predictions with measurements of aerosol optical properties. Third, the simulated hygroscopicity of aerosols is too high as compared to their hygroscopicity derived from cloud condensation nuclei and particle size distribution measurements, indicating uncertainties associated with simulating size-dependent chemical composition and treatment of aerosol mixing state within the model. Fourth, the model reasonably represents the observations of the first aerosol indirect effect where pollutants in the vicinity of Oklahoma City increase cloud droplet number concentrations and decrease the droplet effective radius. While previous studies have often focused on cloud-aerosol interactions in stratiform and deep convective clouds, this study highlights the ability of regional-scale models to represent some of the important aspects of cloud-aerosol interactions associated with fields of short-lived shallow cumuli.

  17. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, P.M.; Reger, R.J.

    1996-02-20

    A variable depth core sampler apparatus is described comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member. 7 figs.

  18. Variable depth core sampler

    DOE Patents [OSTI]

    Bourgeois, Peter M. (Hamburg, NY); Reger, Robert J. (Grand Island, NY)

    1996-01-01

    A variable depth core sampler apparatus comprising a first circular hole saw member, having longitudinal sections that collapses to form a point and capture a sample, and a second circular hole saw member residing inside said first hole saw member to support the longitudinal sections of said first hole saw member and prevent them from collapsing to form a point. The second hole saw member may be raised and lowered inside said first hole saw member.

  19. Carbonaceous Aerosols and Radiative Effects Study (CARES), g1-aircraft, sedlacek sp2

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sedlacek, Art

    The primary objective of the Carbonaceous Aerosol and Radiative Effects Study (CARES) in 2010 was to investigate the evolution of carbonaceous aerosols of different types and their optical and hygroscopic properties in central California, with a focus on the Sacramento urban plume.

  20. Carbonaceous Aerosols and Radiative Effects Study (CARES), g1-aircraft, sedlacek sp2

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sedlacek, Art

    2011-08-30

    The primary objective of the Carbonaceous Aerosol and Radiative Effects Study (CARES) in 2010 was to investigate the evolution of carbonaceous aerosols of different types and their optical and hygroscopic properties in central California, with a focus on the Sacramento urban plume.

  1. RACORO aerosol data processing

    SciTech Connect (OSTI)

    Elisabeth Andrews

    2011-10-31

    The RACORO aerosol data (cloud condensation nuclei (CCN), condensation nuclei (CN) and aerosol size distributions) need further processing to be useful for model evaluation (e.g., GCM droplet nucleation parameterizations) and other investigations. These tasks include: (1) Identification and flagging of 'splash' contaminated Twin Otter aerosol data. (2) Calculation of actual supersaturation (SS) values in the two CCN columns flown on the Twin Otter. (3) Interpolation of CCN spectra from SGP and Twin Otter to 0.2% SS. (4) Process data for spatial variability studies. (5) Provide calculated light scattering from measured aerosol size distributions. Below we first briefly describe the measurements and then describe the results of several data processing tasks that which have been completed, paving the way for the scientific analyses for which the campaign was designed. The end result of this research will be several aerosol data sets which can be used to achieve some of the goals of the RACORO mission including the enhanced understanding of cloud-aerosol interactions and improved cloud simulations in climate models.

  2. GCM parameterization of radiative forcing by Pinatubo aerosols

    SciTech Connect (OSTI)

    Lacis, A.A.; Mishchenko, M.I.

    1996-12-31

    This paper addresses the question of whether the general circulation model (GCM) parameterization of volcanic aerosol forcing can be adequately described in terms of just two physical aerosol parameters: (1) the aerosol column optical thickness and (2) the effective radius of the aerosol size distribution. Data recorded from the eruption of Mt. Pinatubo in the Philippines in June 1991 was analyzed to attempt to answer this question. The spatial distribution of the particle size showed considerable variability and was found to increase steadily following the eruption. The time evolution of the Pinatubo aerosol particle size distribution as derived from satellite data differed significantly, particularly in the early phases of the eruption, from that assumed in the initial GCM simulation of the Pinatubo eruption. A bimodal distribution was used to examine the possibility that the actual size distribution of the volcanic aerosol was multimodal. However, results suggested that in most cases the aerosol size distribution was essentially monomodal in nature. Results from the radiative model used in the calculations are also presented. 11 refs., 6 figs.

  3. IN-DEPTH REPORT: Environmental

    E-Print Network [OSTI]

    in local policy debates about fracking. This In-depth Report from Science for Environment Policy explores

  4. Aerosol collection characteristics of ambient aerosol samplers 

    E-Print Network [OSTI]

    Ortiz, Carlos A

    1978-01-01

    when the sampler is not in operation, both as functions of particle size and wind speed. Wind velocity was a major cause of bias for the four samplers when collecting aerosol particles & 10 um. Characteristic curves were very similar for the 0. 38 m... x 0. 38 m ( 15" x 15") Hi-Vol and the 0. 29 m x 0. 36 m (11&" x 14") Hi-Vol. At 28 um and wind speeds of 2, 8, and 24 km/hr, sampling effectiveness values respectively were 70, 43, and 43 percent for the 0. 38 m x 0. 38 m Hi-Vol and 81, 56, and 43...

  5. Optical Properties of Secondary Organic Aerosols

    E-Print Network [OSTI]

    Kim, Hwajin

    2012-01-01

    J. H. Journal of Atmospheric Chemistry 1997 , 26, 189-193. (induced ageing, Atmospheric Chemistry and Physics, 11(21),emerging issues, Atmospheric Chemistry and Physics, 9(14),

  6. Optical Properties of Secondary Organic Aerosols

    E-Print Network [OSTI]

    Kim, Hwajin

    2012-01-01

    two SOA precursor hydrocarbon measurements within 2% of onetwo SOA precursor hydrocarbon measurements within 2% of onetwo SOA precursor hydrocarbon measurements within 2% of one

  7. ARM - Field Campaign - MASRAD - Aerosol Optical Properties

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach HomeA Better Anode Design to Improve4AJ01)govCampaignsFIRE-Arctic-govCampaignsLower

  8. Maritime Aerosol Network as a component of Aerosol Robotic A. Smirnov,1,2

    E-Print Network [OSTI]

    Maritime Aerosol Network as a component of Aerosol Robotic Network A. Smirnov,1,2 B. N. Holben,2 I of the Maritime Aerosol Network (MAN), which has been developed as a component of the Aerosol Robotic Network), Maritime Aerosol Network as a component of Aerosol Robotic Network, J. Geophys. Res., 114, D06204, doi:10

  9. Modelling of long-range transport of Southeast Asia biomass-burning aerosols to Taiwan and their radiative forcings over East Asia

    SciTech Connect (OSTI)

    Lin, Chuan-Yao; Zhao, Chun; Liu, Xiaohong; Lin, Neng-Huei; Chen, Wei-Nei

    2014-10-12

    Biomass burning is a major source of aerosols and air pollutants during the springtime in Southeast Asia. At Lulin mountain background station (elevation 2862 m) in Taiwan, the concentrations of carbon monoxide (CO), ozone (O3) and particulate matter particles with diameter less than 10 ?m (PM10), were measured around 150-250 ppb, 40-60 ppb, and 10-30?g/m3, respectively at spring time (February-April) during 2006 and 2009, which are about 2~3 times higher than those in other seasons. Observations and simulation results indicate that the higher concentrations during the spring time are clearly related to biomass burning plumes transported from the Indochina Peninsula of Southeast Asia. The spatial distribution of high aerosols optical depth (AOD) were identified by the satellite measurement and Aerosol Robotic Network (AERONET) ground observation, and could be reasonably captured by the WRF-Chem model during the study period of 15-18 March, 2008. AOD reached as high as 0.8-1.0 in Indochina ranging from 10 to 22°N and 95 to 107°E. Organic carbon (OC) is a major contributor of AOD over Indochina according to simulation results. The contributor of AOD from black carbon (BC) is minor when compared with OC over the Indochina. However, the direct absorption radiative forcing of BC in the atmosphere could reach 35-50 W m-2, which is about 8-10 times higher than that of OC. The belt shape of radiation reduction at surface from Indochina to Taiwan could be as high 20-40 W m-2 during the study period. The implication of the radiative forcing from biomass burning aerosols and their impact on the regional climate in East Asia is our major concern.

  10. Aerosol mass spectrometry systems and methods

    DOE Patents [OSTI]

    Fergenson, David P.; Gard, Eric E.

    2013-08-20

    A system according to one embodiment includes a particle accelerator that directs a succession of polydisperse aerosol particles along a predetermined particle path; multiple tracking lasers for generating beams of light across the particle path; an optical detector positioned adjacent the particle path for detecting impingement of the beams of light on individual particles; a desorption laser for generating a beam of desorbing light across the particle path about coaxial with a beam of light produced by one of the tracking lasers; and a controller, responsive to detection of a signal produced by the optical detector, that controls the desorption laser to generate the beam of desorbing light. Additional systems and methods are also disclosed.

  11. Composition and Reactions of Atmospheric Aerosol Particles

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Composition and Reactions of Atmospheric Aerosol Particles Print Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion...

  12. Assessment of long-term WRF–CMAQ simulations for understanding direct aerosol effects on radiation "brightening" in the United States

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gan, C.-M.; Pleim, J.; Mathur, R.; Hogrefe, C.; Long, C. N.; Xing, J.; Wong, D.; Gilliam, R.; Wei, C.

    2015-11-03

    Long-term simulations with the coupled WRF–CMAQ (Weather Research and Forecasting–Community Multi-scale Air Quality) model have been conducted to systematically investigate the changes in anthropogenic emissions of SO2 and NOx over the past 16 years (1995–2010) across the United States (US), their impacts on anthropogenic aerosol loading over North America, and subsequent impacts on regional radiation budgets. In particular, this study attempts to determine the consequences of the changes in tropospheric aerosol burden arising from substantial reductions in emissions of SO2 and NOx associated with control measures under the Clean Air Act (CAA) especially on trends in solar radiation. Extensive analysesmore »conducted by Gan et al. (2014a) utilizing observations (e.g., SURFRAD, CASTNET, IMPROVE, and ARM) over the past 16 years (1995–2010) indicate a shortwave (SW) radiation (both all-sky and clear-sky) "brightening" in the US. The relationship of the radiation brightening trend with decreases in the aerosol burden is less apparent in the western US. One of the main reasons for this is that the emission controls under the CAA were aimed primarily at reducing pollutants in areas violating national air quality standards, most of which were located in the eastern US, while the relatively less populated areas in the western US were less polluted at the beginning of this study period. Comparisons of model results with observations of aerosol optical depth (AOD), aerosol concentration, and radiation demonstrate that the coupled WRF–CMAQ model is capable of replicating the trends well even though it tends to underestimate the AOD. In particular, the sulfate concentration predictions were well matched with the observations. The discrepancies found in the clear-sky diffuse SW radiation are likely due to several factors such as the potential increase of ice particles associated with increasing air traffic, the definition of "clear-sky" in the radiation retrieval methodology, and aerosol semi-direct and/or indirect effects which cannot be readily isolated from the observed data.« less

  13. CARES: Carbonaceous Aerosol and Radiative Effects Study Operations Plan

    SciTech Connect (OSTI)

    Zaveri, RA; Shaw, WJ; Cziczo, DJ

    2010-07-12

    The CARES field campaign is motivated by the scientific issues described in the CARES Science Plan. The primary objectives of this field campaign are to investigate the evolution and aging of carbonaceous aerosols and their climate-affecting properties in the urban plume of Sacramento, California, a mid-size, mid-latitude city that is located upwind of a biogenic volatile organic compound (VOC) emission region. Our basic observational strategy is to make comprehensive gas, aerosol, and meteorological measurements upwind, within, and downwind of the urban area with the DOE G-1 aircraft and at strategically located ground sites so as to study the evolution of urban aerosols as they age and mix with biogenic SOA precursors. The NASA B-200 aircraft, equipped with the High Spectral Resolution Lidar (HSRL), digital camera, and the Research Scanning Polarimeter (RSP), will be flown in coordination with the G-1 to characterize the vertical and horizontal distribution of aerosols and aerosol optical properties, and to provide the vertical context for the G-1 and ground in situ measurements.

  14. Aerosol Observing System Upgraded

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O D S TA I N P A T T E R N A NA LY S IDOE Office2 Aerosol

  15. Parameterizations of Cloud Microphysics and Indirect Aerosol Effects

    SciTech Connect (OSTI)

    Tao, Wei-Kuo

    2014-05-19

    1. OVERVIEW Aerosols and especially their effect on clouds are one of the key components of the climate system and the hydrological cycle [Ramanathan et al., 2001]. Yet, the aerosol effect on clouds remains largely unknown and the processes involved not well understood. A recent report published by the National Academy of Science states "The greatest uncertainty about the aerosol climate forcing - indeed, the largest of all the uncertainties about global climate forcing - is probably the indirect effect of aerosols on clouds [NRC, 2001]." The aerosol effect on clouds is often categorized into the traditional "first indirect (i.e., Twomey)" effect on the cloud droplet sizes for a constant liquid water path [Twomey, 1977] and the "semi-direct" effect on cloud coverage [e.g., Ackerman et al., 2000]. Enhanced aerosol concentrations can also suppress warm rain processes by producing a narrow droplet spectrum that inhibits collision and coalescence processes [e.g., Squires and Twomey, 1961; Warner and Twomey, 1967; Warner, 1968; Rosenfeld, 1999]. The aerosol effect on precipitation processes, also known as the second type of aerosol indirect effect [Albrecht, 1989], is even more complex, especially for mixed-phase convective clouds. Table 1 summarizes the key observational studies identifying the microphysical properties, cloud characteristics, thermodynamics and dynamics associated with cloud systems from high-aerosol continental environments. For example, atmospheric aerosol concentrations can influence cloud droplet size distributions, warm-rain process, cold-rain process, cloud-top height, the depth of the mixed phase region, and occurrence of lightning. In addition, high aerosol concentrations in urban environments could affect precipitation variability by providing an enhanced source of cloud condensation nuclei (CCN). Hypotheses have been developed to explain the effect of urban regions on convection and precipitation [van den Heever and Cotton, 2007 and Shepherd, 2005]. Recently, a detailed spectral-bin microphysical scheme was implemented into the Goddard Cumulus Ensemble (GCE) model. Atmospheric aerosols are also described using number density size-distribution functions. A spectral-bin microphysical model is very expensive from a computational point of view and has only been implemented into the 2D version of the GCE at the present time. The model is tested by studying the evolution of deep tropical clouds in the west Pacific warm pool region and summertime convection over a mid-latitude continent with different concentrations of CCN: a low "clean" concentration and a high "dirty" concentration. The impact of atmospheric aerosol concentration on cloud and precipitation will be investigated. 2. MODEL DESCRIPTION AND CASE STUDIES 2.1 GCE MODEL The model used in this study is the 2D version of the GCE model. Modeled flow is anelastic. Second- or higher-order advection schemes can produce negative values in the solution. Thus, a Multi-dimensional Positive Definite Advection Transport Algorithm (MPDATA) has been implemented into the model. All scalar variables (potential temperature, water vapor, turbulent coefficient and all five hydrometeor classes) use forward time differencing and the MPDATA for advection. Dynamic variables, u, v and w, use a second-order accurate advection scheme and a leapfrog time integration (kinetic energy semi-conserving method). Short-wave (solar) and long-wave radiation as well as a subgrid-scale TKE turbulence scheme are also included in the model. Details of the model can be found in Tao and Simpson (1993) and Tao et al. (2003). 2.2 Microphysics (Bin Model) The formulation of the explicit spectral-bin microphysical processes is based on solving stochastic kinetic equations for the size distribution functions of water droplets (cloud droplets and raindrops), and six types of ice particles: pristine ice crystals (columnar and plate-like), snow (dendrites and aggregates), graupel and frozen drops/hail. Each type is described by a special size distribution function containing 33 categories (bin

  16. Observations of the first aerosol indirect effect in shallow cumuli

    SciTech Connect (OSTI)

    Berg, Larry K.; Berkowitz, Carl M.; Barnard, James C.; Senum, Gunar; Springston, Stephen R.

    2011-02-08

    Data from the Cumulus Humilis Aerosol Processing Study (CHAPS) are used to estimate the impact of both aerosol indirect effects and cloud dynamics on the microphysical and optical properties of shallow cumuli observed in the vicinity of Oklahoma City, Oklahoma. Not surprisingly, we find that the amount of light scattered by the clouds is dominated by their liquid water content (LWC), which in turn is driven by cloud dynamics. However, removing the effect of cloud dynamics by examining the scattering normalized by LWC shows a strong sensitivity of scattering to pollutant loading. These results suggest that even moderately sized cities, like Oklahoma City, can have a measureable impact on the optical properties of shallow cumuli.

  17. eDPS Aerosol Collection

    SciTech Connect (OSTI)

    Venzie, J.

    2015-10-13

    The eDPS Aerosol Collection project studies the fundamental physics of electrostatic aerosol collection for national security applications. The interpretation of aerosol data requires understanding and correcting for biases introduced from particle genesis through collection and analysis. The research and development undertaken in this project provides the basis for both the statistical correction of existing equipment and techniques; as well as, the development of new collectors and analytical techniques designed to minimize unwanted biases while improving the efficiency of locating and measuring individual particles of interest.

  18. Resolution of prestack depth migration Ludek Klimes

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Resolution of prestack depth migration Ludek Klimes Department of Geophysics, Faculty inversion, seismic anisotropy. 1. Introduction A general formulation of prestack depth migration based numerical methods (Claerbout, 1971) is considered in this paper. A common­shot prestack depth migration

  19. Measurement of the Optical Proper-ties of Volcanic Ash

    E-Print Network [OSTI]

    Oxford, University of

    Measurement of the Optical Proper- ties of Volcanic Ash Daniel M. Peters and R. G. Grainger of Volcanic Ash". This project will measure vol- canic ash aerosol extinction spectra and the aerosol particle is required in the analysis of IR satellite observations of ash clouds. Dry, water ice and sulphuric acid

  20. Rotating drum variable depth sampler

    DOE Patents [OSTI]

    Nance, Thomas A. (Aiken, SC); Steeper, Timothy J. (Trenton, SC)

    2008-07-01

    A sampling device for collecting depth-specific samples in silt, sludge and granular media has three chambers separated by a pair of iris valves. Rotation of the middle chamber closes the valves and isolates a sample in a middle chamber.

  1. Practical Analysis of materials with depth varying compositions using FT-IR photoacoustic spectroscopy (PAS)

    SciTech Connect (OSTI)

    J.F. McClelland; R.W. Jones; Siquan Luo

    2004-09-30

    FT-IR photoacoustic spectroscopy (PAS) is discussed as a nondestructive method to probe the molecular composition of materials versus depth on the basis of the analysis of layers of experimentally controllable thickness, which are measured from the sample surface to depths of some tens of micrometers, depending on optical and thermal properties. Computational methods are described to process photoacoustic amplitude and phase spectra for both semi-quantitative and quantitative depth analyses. These methods are demonstrated on layered and gradient samples.

  2. Aerosol penetration through transport lines 

    E-Print Network [OSTI]

    Dileep, V.R.

    1996-01-01

    It is very important to minimize the losses in aerosol transport systems for the Continuous Air Monitors (CAM) to have a prompt and a meaningful alarm and the U.S. Environmental Protection Agency (EPA) also Currently mandates continuous emissions...

  3. X-ray Vision for Aerosol Scientists: LCLS Snapshots of Soot (Narrated)

    ScienceCinema (OSTI)

    None

    2014-06-03

    This short conceptual animation depicts how scientists can now simultaneously capture fractal morphology (structure), chemical composition and nanoscale imagery of individual aerosol particles in flight. These particles, known as "PM2.5" because they are smaller than 2.5 microns in diameter, affect climate by interacting with sunlight and impact human health by entering the lungs. The single LCLS laser pulses travel to the Atomic, Molecular and Optical Sciences (AMO) laboratory in the Near Experimental Hall. As we zoom in, we see deep inside a simplified aerosol inlet, where the complex fractal structure of the soot particles, each one completely unique, is shown. Individual soot particles are then delivered into the pulses of the LCLS beam, which destroys them. X-rays are scattered to the detector before the particle is destroyed, giving information about the morphology of the particle. Ion fragments released in the explosion are sent into a mass spectrometer, which measures their mass-to-charge ratio -- giving scientists information about the chemical composition of the particle. Many different particles are analyzed in this manner, allowing scientists to probe variations in the particles due to changes in their environment before being sent through the aerosol inlet. The final visual of aerosols emitted from a factory is representative of the goal that such LCLS aerosol dynamics experiments can provide critical feedback into modeling and understanding combustion, aerosol processes in manufacturing or aerosol effects on climate change.

  4. Nanomaterials from Aerosols Aerosols are suspensions of liquid or solid particles in a gas. Aerosol particles

    E-Print Network [OSTI]

    Beaucage, Gregory

    changes which are evidenced by changes in the temperature of the oceans and rapid melting of the polar and glacial ice packs. Of pollution sources, aerosols represent the least understood and could potentially

  5. Ultrasonic material hardness depth measurement

    DOE Patents [OSTI]

    Good, Morris S. (Richland, WA); Schuster, George J. (Kennewick, WA); Skorpik, James R. (Kennewick, WA)

    1997-01-01

    The invention is an ultrasonic surface hardness depth measurement apparatus and method permitting rapid determination of hardness depth of shafts, rods, tubes and other cylindrical parts. The apparatus of the invention has a part handler, sensor, ultrasonic electronics component, computer, computer instruction sets, and may include a display screen. The part handler has a vessel filled with a couplant, and a part rotator for rotating a cylindrical metal part with respect to the sensor. The part handler further has a surface follower upon which the sensor is mounted, thereby maintaining a constant distance between the sensor and the exterior surface of the cylindrical metal part. The sensor is mounted so that a front surface of the sensor is within the vessel with couplant between the front surface of the sensor and the part.

  6. Ultrasonic material hardness depth measurement

    DOE Patents [OSTI]

    Good, M.S.; Schuster, G.J.; Skorpik, J.R.

    1997-07-08

    The invention is an ultrasonic surface hardness depth measurement apparatus and method permitting rapid determination of hardness depth of shafts, rods, tubes and other cylindrical parts. The apparatus of the invention has a part handler, sensor, ultrasonic electronics component, computer, computer instruction sets, and may include a display screen. The part handler has a vessel filled with a couplant, and a part rotator for rotating a cylindrical metal part with respect to the sensor. The part handler further has a surface follower upon which the sensor is mounted, thereby maintaining a constant distance between the sensor and the exterior surface of the cylindrical metal part. The sensor is mounted so that a front surface of the sensor is within the vessel with couplant between the front surface of the sensor and the part. 12 figs.

  7. Chemical and Physical Characteristics of Diesel Aerosol | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    and Physical Characteristics of Diesel Aerosol Chemical and Physical Characteristics of Diesel Aerosol 2002 DEER Conference Presentation: University of Minnesota...

  8. Overview of the 2010 Carbonaceous Aerosols and Radiative Effects Study (CARES)

    SciTech Connect (OSTI)

    Zaveri, Rahul A.; Shaw, William J.; Cziczo, D. J.; Schmid, Beat; Ferrare, R.; Alexander, M. L.; Alexandrov, Mikhail; Alvarez, R. J.; Arnott, W. P.; Atkinson, D.; Baidar, Sunil; Banta, Robert M.; Barnard, James C.; Beranek, Josef; Berg, Larry K.; Brechtel, Fred J.; Brewer, W. A.; Cahill, John F.; Cairns, Brian; Cappa, Christopher D.; Chand, Duli; China, Swarup; Comstock, Jennifer M.; Dubey, Manvendra K.; Easter, Richard C.; Erickson, Matthew H.; Fast, Jerome D.; Floerchinger, Cody; Flowers, B. A.; Fortner, Edward; Gaffney, Jeffrey S.; Gilles, Mary K.; Gorkowski, K.; Gustafson, William I.; Gyawali, Madhu S.; Hair, John; Hardesty, Michael; Harworth, J. W.; Herndon, Scott C.; Hiranuma, Naruki; Hostetler, Chris A.; Hubbe, John M.; Jayne, J. T.; Jeong, H.; Jobson, Bertram T.; Kassianov, Evgueni I.; Kleinman, L. I.; Kluzek, Celine D.; Knighton, B.; Kolesar, K. R.; Kuang, Chongai; Kubatova, A.; Langford, A. O.; Laskin, Alexander; Laulainen, Nels S.; Marchbanks, R. D.; Mazzoleni, Claudio; Mei, F.; Moffet, Ryan C.; Nelson, Danny A.; Obland, Michael; Oetjen, Hilke; Onasch, Timothy B.; Ortega, Ivan; Ottaviani, M.; Pekour, Mikhail S.; Prather, Kimberly A.; Radney, J. G.; Rogers, Ray; Sandberg, S. P.; Sedlacek, Art; Senff, Christoph; Senum, Gunar; Setyan, Ari; Shilling, John E.; Shrivastava, ManishKumar B.; Song, Chen; Springston, S. R.; Subramanian, R.; Suski, Kaitlyn; Tomlinson, Jason M.; Volkamer, Rainer M.; Wallace, Hoyt A.; Wang, J.; Weickmann, A. M.; Worsnop, Douglas R.; Yu, Xiao-Ying; Zelenyuk, Alla; Zhang, Qi

    2012-08-22

    Substantial uncertainties still exist in the scientific understanding of the possible interactions between urban and natural (biogenic) emissions in the production and transformation of atmospheric aerosol and the resulting impact on climate change. The U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) program's Carbonaceous Aerosol and Radiative Effects Study (CARES) carried out in June 2010 in Central Valley, California, was a comprehensive effort designed to improve this understanding. The primary objective of the field study was to investigate the evolution of secondary organic and black carbon aerosols and their climate-related properties in the Sacramento urban plume as it was routinely transported into the forested Sierra Nevada foothills area. Urban aerosols and trace gases experienced significant physical and chemical transformations as they mixed with the reactive biogenic hydrocarbons emitted from the forest. Two heavily-instrumented ground sites - one within the Sacramento urban area and another about 40 km to the northeast in the foothills area - were set up to characterize the evolution of meteorological variables, trace gases, aerosol precursors, aerosol size, composition, and climate-related properties in freshly polluted and 'aged' urban air. On selected days, the DOE G-1 aircraft was deployed to make similar measurements upwind and across the evolving Sacramento plume in the morning and again in the afternoon. The NASA B-200 aircraft, carrying remote sensing instruments, was also deployed to characterize the vertical and horizontal distribution of aerosols and aerosol optical properties within and around the plume. This overview provides: a) the scientific background and motivation for the study, b) the operational and logistical information pertinent to the execution of the study, c) an overview of key observations and initial results from the aircraft and ground-based sampling platforms, and d) a roadmap of planned data analyses and focused modeling efforts that will facilitate the integration of new knowledge into improved representations of key aerosol processes in climate models.

  9. Swept source optical coherence microscopy for pathological assessment of cancerous tissues

    E-Print Network [OSTI]

    Ahsen, Osman Oguz

    2013-01-01

    Optical coherence microscopy (OCM) combines optical coherence tomography (OCT) with confocal microscopy and enables depth resolved visualization of biological specimens with cellular resolution. OCM offers a suitable ...

  10. Assessing the Radiative Impact of Clouds of Low Optical Depth

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O DBiomass and Biofuels BiomassAssembly of aCloud Spatialthe

  11. Toxicity of atmospheric aerosols on marine phytoplankton

    E-Print Network [OSTI]

    2009-01-01

    address: Center for Atmospheric Chemistry Study, Departmenttween phytoplankton, atmospheric chemistry, and climate areno. 12 ? 4601– 4605 CHEMISTRY Atmospheric aerosol deposition

  12. 4, 20552088, 2004 Aerosol-ozone

    E-Print Network [OSTI]

    Boyer, Edmond

    ACPD 4, 2055­2088, 2004 Aerosol-ozone correlations during dust transport episodes P. Bonasoni et al and Physics Discussions Aerosol-ozone correlations during dust transport episodes P. Bonasoni1 , P.bonasoni@isac.cnr.it) 2055 #12;ACPD 4, 2055­2088, 2004 Aerosol-ozone correlations during dust transport episodes P. Bonasoni

  13. Real time infrared aerosol analyzer

    DOE Patents [OSTI]

    Johnson, Stanley A. (Countryside, IL); Reedy, Gerald T. (Bourbonnais, IL); Kumar, Romesh (Naperville, IL)

    1990-01-01

    Apparatus for analyzing aerosols in essentially real time includes a virtual impactor which separates coarse particles from fine and ultrafine particles in an aerosol sample. The coarse and ultrafine particles are captured in PTFE filters, and the fine particles impact onto an internal light reflection element. The composition and quantity of the particles on the PTFE filter and on the internal reflection element are measured by alternately passing infrared light through the filter and the internal light reflection element, and analyzing the light through infrared spectrophotometry to identify the particles in the sample.

  14. Optical Properties of Saharan Dust and Asian Dust: Application to Radiative Transfer Simulations 

    E-Print Network [OSTI]

    Fang, Guangyang

    2012-07-16

    an important role in climate change, the majorities of aerosols are natural ones and can impact cloud properties, convective cloud dynamics, and the development of tropical storms (Jones et al. 2004). The optical properties of mineral dust aerosols... dusts from the Rayleigh regime to the geometric optics regime. A database of the optical properties of randomly oriented spheroids has been developed. 4.1 Geometry of the dust particle model The geometry of the spheroidal model used is shown...

  15. Decoupled elastic prestack depth migration Alexander Druzhinin*

    E-Print Network [OSTI]

    Edinburgh, University of

    Decoupled elastic prestack depth migration $ Alexander Druzhinin* British Geological Survey of the formula for common-shot or common-receiver amplitude-preserving elastic prestack depth migration (Pre to enhance strongly polarized wave modes prior to prestack depth migration (PreSDM) (e.g. Dillon et al., 1988

  16. Resolution of prestack depth migration Ludek Klimes

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Resolution of prestack depth migration Ludek Klimes Department of Geophysics, Faculty of a general 3­D common­shot elastic prestack depth migration in a heterogeneous anisotropic medium is studied. Geophys. AS CR, Prague 457 #12;L. Klimes 1. INTRODUCTION A general formulation of prestack depth migration

  17. Stratospheric Albedo Modification by Aerosol Injection

    E-Print Network [OSTI]

    Katz, J I

    2009-01-01

    This paper reviews and develops the proposal, widely discussed but not examined in detail, to use stratospheric aerosols to increase the Earth's albedo to Solar radiation in order to control climate change. The potential of this method has been demonstrated by the "natural experiments" of volcanic injection of sulfate aerosols into the stratosphere that led to subsequent observed global cooling. I consider several hygroscopic oxides as possible aerosol materials in addition to oxides of sulfur. Aerosol chemistry, dispersion and transport have been the subject of little study and are not understood, representing a significant scientific risk. Even the optimal altitude of injection and aerosol size distribution are poorly known. Past attention focused on guns and airplanes as means of lofting aerosols or their chemical precursors, but large sounding rockets are cheap, energetically efficient, can be designed to inject aerosols at any required altitude, and involve little technical risk. Sophisticated, mass-opti...

  18. Stratospheric Aerosol Geoengineering ALAN ROBOCK

    E-Print Network [OSTI]

    Robock, Alan

    hydrologic responses, whitening of the skies, reduction of solar power, and impacts of diffuse radiation Project, conducting climate model experiments with standard stratospheric aerosol in- jection scenarios, which stated that ``It is extremely likely that human in- fluence has been the dominant cause

  19. Characterization of the Sunset Semi-Continuous Carbon Aerosol Analyzer

    SciTech Connect (OSTI)

    Bauer, Jace J.; Yu, Xiao-Ying; Cary, R.; Laulainen, Nels S.; Berkowitz, Carl M.

    2009-07-01

    Accurate quantification of carbonaceous aerosols is essential for reducing uncertainty in climate change models and is important for long-term air quality monitoring by government agencies. The field-deployable Sunset Semi-Continuous Organic Carbon/Elemental Carbon Aerosol Analyzer (Sunset OCEC) utilizes a modified National Institute for Occupational Safety and Health thermal-optical method to determine total carbon (TC), organic carbon (OC), and elemental carbon (EC) at near real-time; however, its performance is not yet fully characterized. Two collocated Sunset OCEC Analyzers, Unit A and Unit B, were used to determine the relative standard deviation (RSD) and limit of detection (LOD) between June 23 and July 9, 2007, in Richland, Washington, USA. A high-efficiency particulate air filter was utilized to determine the LODs of both instruments. The RSDs between the two Sunset OCECs were 9.12% for TC, 13.0% for Optical OC, and 8.97% for Thermal OC, indicating good precision between the instruments, although the RSDs for Thermal and Optical EC were higher, 29.0% and 48.3%, respectively. The LOD of Unit A was approximately 0.21 µgC/m3 for TC, Optical OC, and Thermal OC, and ~0.004 µgC/m3 for Optical and Thermal EC. Similarly, Unit B had an LOD of ~0.29 µgC/m3 for TC, Optical OC, and Thermal OC, 0.018 µgC/m3 for Optical EC, and 0.004 µgC/m3 for Thermal EC. Factors that may have contributed to the poor RSDs of Thermal and Optical EC include the low EC mass loading in Richland, minor leakage in the oxygen valve of Unit B, and excessive noise from the non-dispersive infrared (NDIR) laser in Unit B, resulting in scattered Optical EC measurements. Improved RSDs of all OC and EC parameters are expected after the Unit B NDIR is tuned up. Future work should reevaluate the precision of the Sunset OCECs and investigate the differences in various thermal-optical protocols on OCEC quantification.

  20. DO AEROSOLS CHANGE CLOUD COVER AND AFFECT CLIMATE?

    E-Print Network [OSTI]

    Schwartz, Stephen E.

    IN MEXICO CITY BASIN Light scattering by aerosols decreases absorption of solar radiation. #12;AEROSOLS;AEROSOL INFLUENCES ON CLIMATE AND CLIMATE CHANGE #12;DMS #12;AEROSOL IN MEXICO CITY BASIN #12;AEROSOL AS SEEN FROM SPACE Fire plumes from southern Mexico transported north into Gulf of Mexico. #12;CLOUD

  1. Aerosol Properties from Multi-spectral and Multi-angular Aircraft 4STAR Observations: Expected Advantages and Challenges

    SciTech Connect (OSTI)

    Kassianov, Evgueni I.; Flynn, Connor J.; Redemann, Jens; Schmid, Beat; Russell, P. B.; Sinyuk, Alexander

    2012-11-01

    The airborne Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) is developed to retrieve aerosol microphysical and optical properties from multi-angular and multi-spectral measurements of sky radiance and direct-beam sun transmittance. The necessarily compact design of the 4STAR may cause noticeable apparent enhancement of sky radiance at small scattering angles. We assess the sensitivity of expected 4STAR-based aerosol retrieval to such enhancement by applying the operational AERONET retrieval code and constructed synthetic 4STARlike data. Also, we assess the sensitivity of the broadband fluxes and the direct aerosol radiative forcing to uncertainties in aerosol retrievals associated with the sky radiance enhancement. Our sensitivity study results suggest that the 4STARbased aerosol retrieval has limitations in obtaining detailed information on particle size distribution and scattering phase function. However, these limitations have small impact on the retrieved bulk optical parameters, such as the asymmetry factor (up to 4%, or ±0.02) and single-scattering albedo (up to 2%, or ±0.02), and the calculated direct aerosol radiative forcing (up to 6%, or 2 Wm-2).

  2. Examination of the Effects of Sea Salt Aerosols on Southeast Texas Ozone and Secondary Organic Aerosol 

    E-Print Network [OSTI]

    Benoit, Mark David

    2013-02-06

    of this research is to examine sea salt aerosols and their impact on polluted environments. Sea salt aerosols act as Cloud Condensation Nuclei (CCN) as well as providing a surface for heterogeneous reactions. Such reactions have implications for trace gases...

  3. OPTI 202R Geometrical and Instrumental Optics II Spring 2012

    E-Print Network [OSTI]

    Arizona, University of

    and Relay Lenses Eyepieces Microscopes Vignetting Telecentric Systems Optical Materials and Dispersion Prism Spectrometer Abbe Refractometer Rainbows Thin Prisms Achromatic Thin Prism #12;2 Achromatic Doublet Depth

  4. Measurement of the Optical Proper-ties of Volcanic Ash: Current status.

    E-Print Network [OSTI]

    Oxford, University of

    Measurement of the Optical Proper- ties of Volcanic Ash: Current status. Daniel M. Peters and R. G project "Opti- cal Properties of Volcanic ash". This project sets out to measure the extinction spectra and size distribution of volcanic ash aerosol. The measurements will allow the calculation of aerosol cross

  5. Aerosol Science and Technology, 43:641652, 2009 Copyright American Association for Aerosol Research

    E-Print Network [OSTI]

    Aerosol Science and Technology, 43:641­652, 2009 Copyright © American Association for Aerosol Differential Mobility Analyzer for Measurement of the Irreversibility of the Hygroscopic Growth Factor T is the irreversibility of the hygroscopic growth fac- tor of aerosol particles. The instrument uses the hysteresis

  6. Aerosol characterization study using multi-spectrum remote sensing measurement techniques.

    SciTech Connect (OSTI)

    Glen, Crystal Chanea; Sanchez, Andres L.; Lucero, Gabriel Anthony; Schmitt, Randal L.; Johnson, Mark S.; Tezak, Matthew Stephen; Servantes, Brandon Lee

    2013-09-01

    A unique aerosol flow chamber coupled with a bistatic LIDAR system was implemented to measure the optical scattering cross sections and depolarization ratio of common atmospheric particulates. Each of seven particle types (ammonium sulfate, ammonium nitrate, sodium chloride, potassium chloride, black carbon and Arizona road dust) was aged by three anthropogenically relevant mechanisms: 1. Sulfuric acid deposition, 2. Toluene ozonolysis reactions, and 3. m-Xylene ozonolysis reactions. The results of pure particle scattering properties were compared with their aged equivalents. Results show that as most particles age under industrial plume conditions, their scattering cross sections are similar to pure black carbon, which has significant impacts to our understanding of aerosol impacts on climate. In addition, evidence emerges that suggest chloride-containing aerosols are chemically altered during the organic aging process. Here we present the direct measured scattering cross section and depolarization ratios for pure and aged atmospheric particulates.

  7. Researchers Model Impact of Aerosols Over California

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Impact of Aerosols Over California Research may clarify the effectiveness of regional pollution controls May 28, 2013 | Tags: Climate Research, Hopper Contact: Linda Vu,...

  8. Aerosol Retrieval Using Remote-sensed Observations

    E-Print Network [OSTI]

    Wang, Yueqing

    2012-01-01

    4.1.2 Baltimore and the DRAGONaround Baltimore . . . . . . . . . . . . . . . . . . . 4.1.4component aerosol 1 for Baltimore-Washington region on June

  9. Composition and Reactions of Atmospheric Aerosol Particles

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    they can have either cooling or warming effects. Lighter-colored organic carbon particles cool regions of the planet by scattering sunlight back into space. Other aerosol particles...

  10. Composition and Reactions of Atmospheric Aerosol Particles

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    on high-resolution scanning transmission x-ray images obtained at the ALS have revealed chemical reactions on and in atmospheric aerosol particles that caused particle growth...

  11. Extending the physicochemical characterization of aerosol particles in California

    E-Print Network [OSTI]

    Zauscher, Melanie Dorothy

    2012-01-01

    Combustion Aerosol, Atmospheric Chemistry and Physics, 11 (Based Receptor Modeling, Atmospheric Chemistry and Physics,Aerosols, Journal of Atmospheric Chemistry, 22 (1-2), 19-39.

  12. Building America Webinar: Sealing of Home Enclosures with Aerosol...

    Energy Savers [EERE]

    Sealing of Home Enclosures with Aerosol Particles Building America Webinar: Sealing of Home Enclosures with Aerosol Particles This webinar was presented by research team Building...

  13. The Indirect and Semi-Direct Aerosol Campaign

    SciTech Connect (OSTI)

    Ghan, Steve

    2014-03-24

    Research projects like the Indirect and Semi-Direct Aerosol Campaign, or ISDAC, increase our knowledge of atmospheric aerosol particles and cloud physics.

  14. ARM - Field Campaign - Aerosol and Cloud Experiments in the Eastern...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    horizontal variabilities of aerosol, trace gases, cloud, drizzle, and atmospheric thermodynamics are critically needed for understanding and quantifying the budget of MBL aerosol,...

  15. The Indirect and Semi-Direct Aerosol Campaign

    ScienceCinema (OSTI)

    Ghan, Steve

    2014-06-12

    Research projects like the Indirect and Semi-Direct Aerosol Campaign, or ISDAC, increase our knowledge of atmospheric aerosol particles and cloud physics.

  16. Carbonaceous Aerosol Study Using Advanced Particle Instrumentation

    E-Print Network [OSTI]

    Qi, Li

    2010-01-01

    6 6.1 Introduction Biomass combustion emissions contributeEmissions of trace gases and aerosols during the open combustion of biomassbiomass burning work explored the evolution of organic aerosol emissions as a function of modified combustion efficiency with correlations drawn between levoglucosan emissions

  17. Optimal Estimation Retrieval Aerosol Microphysical Properties

    E-Print Network [OSTI]

    Oxford, University of

    ) the validation of this algorithm on the basis of synthetic extinction data, and (3) application of the new algorithm to SAGE II measurements of stratospheric background aerosol. The validation results indicate that the new method is able to retrieve the particle size of typical background aerosols reasonably well

  18. Atmospheric aerosol light scattering and polarization peculiarities

    E-Print Network [OSTI]

    Patlashenko, Zh I

    2015-01-01

    This paper considers environmental problems of natural and anthropogenic atmospheric aerosol pollution and its global and regional monitoring. Efficient aerosol investigations may be achieved by spectropolarimetric measurements. Specifically second and fourth Stokes parameters spectral dependencies carry information on averaged refraction and absorption indexes and on particles size distribution functions characteristics.

  19. AEROSOL PARTICLE COLLECTOR DESIGN STUDY

    SciTech Connect (OSTI)

    Lee, S; Richard Dimenna, R

    2007-09-27

    A computational evaluation of a particle collector design was performed to evaluate the behavior of aerosol particles in a fast flowing gas stream. The objective of the work was to improve the collection efficiency of the device while maintaining a minimum specified air throughput, nominal collector size, and minimal power requirements. The impact of a range of parameters was considered subject to constraints on gas flow rate, overall collector dimensions, and power limitations. Potential improvements were identified, some of which have already been implemented. Other more complex changes were identified and are described here for further consideration. In addition, fruitful areas for further study are proposed.

  20. ARM Cloud Aerosol Precipitation Experiment

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsicloudden Documentation Data Management Facility PlotsProducts (VAP) VAP38 ARM6Aerosol

  1. Control of electrode depth in electroslag remelting

    DOE Patents [OSTI]

    Melgaard, David K. (Albuquerque, NM); Shelmidine, Gregory J. (Tijeras, NM); Damkroger, Brian K. (Albuquerque, NM)

    2002-01-01

    A method of and apparatus for controlling an electroslag remelting furnace by driving the electrode at a nominal speed based upon melting rate and geometry while making minor proportional adjustments based on a measured metric of the electrode immersion depth. Electrode drive speed is increased if a measured metric of electrode immersion depth differs from a set point by a predetermined amount, indicating that the tip is too close to the surface of a slag pool. Impedance spikes are monitored to adjust the set point for the metric of electrode immersion depth based upon one or more properties of the impedance spikes.

  2. Optical coherent transients in cold atoms: From free-induction decay to optical precursors

    SciTech Connect (OSTI)

    Chen, J. F.; Wang Shuyuan; Wei Dong; Loy, M. M. T.; Wong, G. K. L.; Du Shengwang [Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)

    2010-03-15

    We report theoretical and experimental studies of the propagation of a square-modulated laser pulse through a laser-cooled atomic ensemble of two-level absorbers, as well as through a three-level system with electromagnetically induced transparency. We find that the transmission characteristics over a wide range of optical depth can be fully accounted for as optical coherent transients excited by the wide spectral content of the square-modulated optical pulse. We show that both time-domain atom-field coupled equations and frequency-domain linear dispersion theory give precisely the same description of the optical transients at a weak power limit. At low optical depth with moderate absorption, resonant excitation dominates and free-induction decay (FID) contributes mostly to the transient field. At high optical depth when absorption and propagation effects become significant, lossless optical precursors start to dominate the transient response. By varying the optical depth from 0 to 45, we observe that optical transients evolve gradually from FID to optical precursors. We thus show that FID and optical precursors, which have been considered as two different optical transients for many decades, can be unified within a single theoretical frame and they are the manifestations of the same physical process in two different regimes.

  3. AEROSOL ABSORPTION IN CLOUDY SCENES USING PASSIVE SATELLITE INSTRUMENTS

    E-Print Network [OSTI]

    Graaf, Martin de

    AEROSOL ABSORPTION IN CLOUDY SCENES USING PASSIVE SATELLITE INSTRUMENTS M. de Graaf, L.G. Tilstra information has become available from active space-based sensors and some dedicated field campaigns on aerosol-absorption, is the Absorbing Aerosol Index (AAI), which can indicate absorbing aerosols overlying clouds. The AAI is available

  4. Studying trends in biomass burning aerosol using the Absorbing Aerosol Index derived from GOME, SCIAMACHY, and GOME-2

    E-Print Network [OSTI]

    Tilstra, Gijsbert

    Studying trends in biomass burning aerosol using the Absorbing Aerosol Index derived from GOME the resulting time series, we use tropospheric NO2 data as a reference in the regions dominated by biomass sensitive to desert dust aerosols (DDA) and biomass burning aerosols (BBA). See Figure 1. The AAI

  5. Atmospheric aerosol optical property retrieval with scanning polarimeters

    E-Print Network [OSTI]

    scatter and absorb incident solar radiation and emitted infra-red radiation. Climate models simulate Mexico suspended over low altitude marine stratocumulus clouds in the Gulf of Mexico. These studies

  6. ARM - Routine AAF Clouds with Low Optical Water Depths (CLOWD) Optical

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments?govInstrumentsnoaacrnBarrow, Alaska OutreachCalendarPress ReleasesHighlightsNotableRadiative Observations

  7. Group Report: Connections between Aerosol Properties

    E-Print Network [OSTI]

    effect and causes surface warming. Absorption of solar or thermal radiation within the atmospheric column-influencing constituents (such as green- house gases) by this process, anthropogenic aerosols can contribute to climate

  8. Aerosol Condensational Growth in Cloud Formation 

    E-Print Network [OSTI]

    Geng, Jun

    2010-10-12

    A code for the quasi-stationary solution of the coupled heat and mass transport equations for aerosols in a finite volume was developed. Both mass and heat are conserved effectively in the volume, which results in a ...

  9. Aerosol fabrication methods for monodisperse nanoparticles

    DOE Patents [OSTI]

    Jiang, Xingmao; Brinker, C Jeffrey

    2014-10-21

    Exemplary embodiments provide materials and methods for forming monodisperse particles. In one embodiment, the monodisperse particles can be formed by first spraying a nanoparticle-containing dispersion into aerosol droplets and then heating the aerosol droplets in the presence of a shell precursor to form core-shell particles. By removing either the shell layer or the nanoparticle core of the core-shell particles, monodisperse nanoparticles can be formed.

  10. Electrically Driven Technologies for Radioactive Aerosol Abatement

    SciTech Connect (OSTI)

    David W. DePaoli; Ofodike A. Ezekoye; Costas Tsouris; Valmor F. de Almeida

    2003-01-28

    The purpose of this research project was to develop an improved understanding of how electriexecy driven processes, including electrocoalescence, acoustic agglomeration, and electric filtration, may be employed to efficiently treat problems caused by the formation of aerosols during DOE waste treatment operations. The production of aerosols during treatment and retrieval operations in radioactive waste tanks and during thermal treatment operations such as calcination presents a significant problem of cost, worker exposure, potential for release, and increased waste volume.

  11. Development of plutonium aerosol fractionation system 

    E-Print Network [OSTI]

    Mekala, Malla R.

    1993-01-01

    DEVELOPMENT OF A PLUTONIUM AEROSOL FRACTIONATION SYSTEM A Thesis by MALLA R. MEKALA Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE August... 1993 Major Subject: Mechanical Engineering DEVELOPMENT OP A PLUTONIUM AEROSOL FRACTIONATION SYSTEM A Thesis by MALLA R. MEKALA Approved as to style and content by: A. R. McFarland (Chair of Committee) N. K. Anand (Mer toer) (', & C. B...

  12. Optical Fibers Optics and Photonics

    E-Print Network [OSTI]

    Palffy-Muhoray, Peter

    Optical Fibers Optics and Photonics Dr. Palffy-Muhoray Ines Busuladzic Department of Theoretical and Applied Mathematics The University of Akron April 21, 2008 #12;Outline · History of optical fibers · What are optical fibers? · How are optical fibers made? · Light propagation through optical fibers · Application

  13. The Square Root Depth Wave Equations

    E-Print Network [OSTI]

    Colin C. Cotter; Darryl D. Holm; James R. Percival

    2009-12-11

    We introduce a set of coupled equations for multilayer water waves that removes the ill-posedness of the multilayer Green-Naghdi (MGN) equations in the presence of shear. The new well-posed equations are Hamiltonian and in the absence of imposed background shear they retain the same travelling wave solutions as MGN. We call the new model the Square Root Depth equations, from the modified form of their kinetic energy of vertical motion. Our numerical results show how the Square Root Depth equations model the effects of multilayer wave propagation and interaction, with and without shear.

  14. Aerosol-cloud radiative effects from passive satellite instruments Mar%n de Graaf

    E-Print Network [OSTI]

    Graaf, Martin de

    Satellite measurements of absorbing aerosols Reflectance Difference Method Cloud modelling Results Outlook Aerosol-Radiation Interac. Aerosol-Cloud Interac. Total anthropogenic Solar irradiance #12;Absorbing aerosols: SCIAMACHY Results Outlook #12;SCIAMACHY on ESA's Environmetal Satellite: ENVISAT Polar orbi

  15. Project Overview: Cumulus Humilis Aerosol Processing Study (CHAPS): Proposed Summer 2007 ASP Field Campaign

    SciTech Connect (OSTI)

    Berkowitz, Carl M.; Berg, Larry K.; Ogren, J. A.; Hostetler, Chris A.; Ferrare, Richard

    2006-05-18

    This white paper presents the scientific motivation and preliminary logistical plans for a proposed ASP field campaign to be carried out in the summer of 2007. The primary objective of this campaign is to use the DOE Gulfstream-1 aircraft to make measurements characterizing the chemical, physical and optical properties of aerosols below, within and above large fields of fair weather cumulus and to use the NASA Langley Research Center’s High Spectral Resolution Lidar (HSRL) to make independent measurements of aerosol backscatter and extinction profiles in the vicinity of these fields. Separate from the science questions to be addressed by these observations will be information to add in the development of a parameterized cumulus scheme capable of including multiple cloud fields within a regional or global scale model. We will also be able to compare and contrast the cloud and aerosol properties within and outside the Oklahoma City plume to study aerosol processes within individual clouds. Preliminary discussions with the Cloud and Land Surface Interaction Campaign (CLASIC) science team have identified overlap between the science questions posed for the CLASIC Intensive Operation Period (IOP) and the proposed ASP campaign, suggesting collaboration would benefit both teams.

  16. Depth Profiling Of Small Molecule Ingress Into Planar and Cylindrical Materials Using NRA and PIXE

    SciTech Connect (OSTI)

    Smith, Richard W.; Massingham, Gary; Clough, Anthony S. [Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH (United Kingdom)

    2003-08-26

    The use of a 3He ion micro-beam technique to study the ingress/diffusion of water into a planar fibre optic grade glass and a cylindrical drug-release polymer is described. One-dimensional concentration profiles showing the depth of water ingress were produced. The depth of penetration of water into the glass was measured by fitting a gaussian function to the concentration profile. The ingress of water into the drug-release polymer was found to be Fickian and a cylindrical diffusion model used to obtain a diffusion coefficient.

  17. Aerosol Science and Technology, 48:803812, 2014 Copyright C American Association for Aerosol Research

    E-Print Network [OSTI]

    Aerosol Science and Technology, 48:803­812, 2014 Copyright C American Association for Aerosol of particle growth in the atmosphere, and many properties of the resulting mixed particles depend on organic. In this article, analytic equations are derived p(;d) for condensational growth in a continuously mixed flow

  18. Aerosol Science and Technology, 45:244261, 2011 Copyright American Association for Aerosol Research

    E-Print Network [OSTI]

    Aerosol Science and Technology, 45:244­261, 2011 Copyright © American Association for Aerosol University, Cambridge, Massachusetts, USA The hygroscopic phase transitions and growth factors of mixed chemical composition on phase transitions. The hygroscopic growth factors of the mixed particles were

  19. Aerosol Science and Technology, 38:12061222, 2004 Copyright c American Association for Aerosol Research

    E-Print Network [OSTI]

    Jimenez, Jose-Luis

    to Combustion-Generated Soot Aerosols as a Function of Fuel Equivalence Ratio Jay G. Slowik,1 K. Stainken,1 Paul factor, size, and fractal dimension of soot aerosol particles generated in a propane/O2 flame were on the fuel equivalence ratio. Type 1: for propane/O2), dva was nearly constant and independent

  20. Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds

    SciTech Connect (OSTI)

    Turner, David, D.; Ferrare, Richard, A.

    2011-07-06

    The 'Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds' project focused extensively on the analysis and utilization of water vapor and aerosol profiles derived from the ARM Raman lidar at the Southern Great Plains ARM site. A wide range of different tasks were performed during this project, all of which improved quality of the data products derived from the lidar or advanced the understanding of atmospheric processes over the site. These activities included: upgrading the Raman lidar to improve its sensitivity; participating in field experiments to validate the lidar aerosol and water vapor retrievals; using the lidar aerosol profiles to evaluate the accuracy of the vertical distribution of aerosols in global aerosol model simulations; examining the correlation between relative humidity and aerosol extinction, and how these change, due to horizontal distance away from cumulus clouds; inferring boundary layer turbulence structure in convective boundary layers from the high-time-resolution lidar water vapor measurements; retrieving cumulus entrainment rates in boundary layer cumulus clouds; and participating in a field experiment that provided data to help validate both the entrainment rate retrievals and the turbulent profiles derived from lidar observations.

  1. Aerosol Characterization Data from the Asian Pacific Regional Aerosol Characterization Project (ACE-Asia)

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The Aerosol Characterization Experiments (ACE) were designed to increase understanding of how atmospheric aerosol particles affect the Earth's climate system. These experiments integrated in-situ measurements, satellite observations, and models to reduce the uncertainty in calculations of the climate forcing due to aerosol particles and improve the ability of models to predict the influences of aerosols on the Earth's radiation balance. ACE-Asia was the fourth in a series of experiments organized by the International Global Atmospheric Chemistry (IGAC) Program (A Core Project of the International Geosphere Biosphere Program). The Intensive Field Phase for ACE-Asia took place during the spring of 2001 (mid-March through early May) off the coast of China, Japan and Korea. ACE-Asia pursued three specific objectives: 1) Determine the physical, chemical, and radiative properties of the major aerosol types in the Eastern Asia and Northwest Pacific region and investigate the relationships among these properties. 2) Quantify the physical and chemical processes controlling the evolution of the major aerosol types and in particular their physical, chemical, and radiative properties. 3) Develop procedures to extrapolate aerosol properties and processes from local to regional and global scales, and assess the regional direct and indirect radiative forcing by aerosols in the Eastern Asia and Northwest Pacific region [Edited and shortened version of summary at http://data.eol.ucar.edu/codiac/projs?ACE-ASIA]. The Ace-Asia collection contains 174 datasets.

  2. Atmospheric Radiation Measurement (ARM) Data from Shouxian, China for the Study of Aerosol Indirect Effects in China

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    In a complex ARM Mobile Facility (AMF) deployment, monitoring data was collected at four locations in China during 2008. The various sites are located in regions with different climate regimes and with high aerosol loadings of different optical, physical, and chemical properties. Measurements obtained at all the AMF sites during the 8-month deployment in China will help scientists to validate satellite-based findings, understand the mechanisms of the aerosol indirect effects in the region, and examine the roles of aerosols in affecting regional climate and atmospheric circulation, with a special focus on the impact of the East Asian monsoon system. As with other collections from the ARM Mobile Facility, the datasets are available from the ARM Archive. The ARM Archive physically resides at the Oak Ridge National Laboratory.

  3. Exploring Virtual Depth for Automotive Instrument Cluster

    E-Print Network [OSTI]

    Exploring Virtual Depth for Automotive Instrument Cluster Concepts Nora Broy1,2,3 , Benedikt Zierer instrument cluster. Permission to make digital or hard copies of part or all of this work for personal more pronounced as auto-stereoscopic displays become available for the car. For instance, H¨akkil¨a et

  4. Saharan dust as a causal factor of hemispheric asymmetry in aerosols and cloud cover over the tropical Atlantic Ocean

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kishcha, Pavel; Da Sliva, Arlindo; Starobinets, Boris; Long, Charles N.; Kalashnikova, Olga; Alpert, Pinhas

    2015-07-09

    Meridional distribution of aerosol optical thickness (AOT) over the tropical Atlantic Ocean (30°N – 30°S) was analyzed to assess seasonal variations of meridional AOT asymmetry. Ten-year MERRA Aerosol Reanalysis (MERRAero) data (July 2002 – June 2012) confirms that the Sahara desert emits a significant amount of dust into the atmosphere over the Atlantic Ocean. Only over the Atlantic Ocean did MERRAero show that desert dust dominates other aerosol species and is responsible for meridional aerosol asymmetry between the tropical North and South Atlantic. Over the 10-year period under consideration, both MISR measurements and MERRAero data showed a pronounced meridional AOTmore »asymmetry. The meridional AOT asymmetry, characterized by the hemispheric ratio (RAOT) of AOT averaged separately over the North and over the South Atlantic, was about 1.7. Seasonally, meridional AOT asymmetry over the Atlantic was the most pronounced between March and July, when dust presence is maximal (RAOT ranged from 2 to 2.4). There was no noticeable meridional aerosol asymmetry in total AOT from September to October. During this period the contribution of carbonaceous aerosols to total AOT in the South Atlantic was comparable to the contribution of dust aerosols to total AOT in the North Atlantic. During the same 10-year period, MODIS cloud fraction (CF) data showed that there was no noticeable asymmetry in meridional CF distribution in different seasons (the hemispheric ratio of CF ranged from 1.0 to 1.2). MODIS CF data illustrated significant cloud cover (CF of 0.7 – 0.9) with limited precipitation ability along the Saharan Air Layer.« less

  5. Non-intrusive characterization of heat transfer fluid aerosol formation 

    E-Print Network [OSTI]

    Krishna, Kiran

    2001-01-01

    in process equipment. Predictive models relating the aerosol formation distances, aerosol droplet size, and volume concentrations to bulk liquid pressure, temperature, fluid properties, leak size and ambient conditions are developed. These models will be used...

  6. Apparatus for rapid measurement of aerosol bulk chemical composition

    DOE Patents [OSTI]

    Lee, Yin-Nan E.; Weber, Rodney J.; Orsini, Douglas

    2006-04-18

    An apparatus for continuous on-line measurement of chemical composition of aerosol particles with a fast time resolution is provided. The apparatus includes an enhanced particle size magnifier for producing activated aerosol particles and an enhanced collection device which collects the activated aerosol particles into a liquid stream for quantitative analysis by analytical means. Methods for on-line measurement of chemical composition of aerosol particles are also provided, the method including exposing aerosol carrying sample air to hot saturated steam thereby forming activated aerosol particles; collecting the activated aerosol particles by a collection device for delivery as a jet stream onto an impaction surface; and flushing off the activated aerosol particles from the impaction surface into a liquid stream for delivery of the collected liquid stream to an analytical instrument for quantitative measurement.

  7. Apparatus for rapid measurement of aerosol bulk chemical composition

    DOE Patents [OSTI]

    Lee, Yin-Nan E. (East Setauket, NY); Weber, Rodney J. (Atlanta, GA)

    2003-01-01

    An apparatus and method for continuous on-line measurement of chemical composition of aerosol particles with a fast time resolution are provided. The apparatus includes a modified particle size magnifier for producing activated aerosol particles and a collection device which collects the activated aerosol particles into a liquid stream for quantitative analysis by analytical methods. The method provided for on-line measurement of chemical composition of aerosol particles includes exposing aerosol carrying sample air to hot saturated steam thereby forming activated aerosol particles; collecting the activated aerosol particles by a collection device for delivery as a jet stream onto an impaction surface; flushing off the activated aerosol particles from the impaction surface into a liquid stream for delivery of the collected liquid stream to an analytical instrument for quantitative measurement.

  8. Global and regional modeling of clouds and aerosols in the marine boundary layer during VOCALS: the VOCA intercomparison

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wyant, M. C.; Bretherton, Christopher S.; Wood, Robert; Carmichael, Gregory; Clarke, A. D.; Fast, Jerome D.; George, R.; Gustafson, William I.; Hannay, Cecile; Lauer, Axel; et al

    2015-01-09

    A diverse collection of models are used to simulate the marine boundary layer in the southeast Pacific region during the period of the October–November 2008 VOCALS REx (VAMOS Ocean Cloud Atmosphere Land Study Regional Experiment) field campaign. Regional models simulate the period continuously in boundary-forced free-running mode, while global forecast models and GCMs (general circulation models) are run in forecast mode. The models are compared to extensive observations along a line at 20° S extending westward from the South American coast. Most of the models simulate cloud and aerosol characteristics and gradients across the region that are recognizably similar tomore »observations, despite the complex interaction of processes involved in the problem, many of which are parameterized or poorly resolved. Some models simulate the regional low cloud cover well, though many models underestimate MBL (marine boundary layer) depth near the coast. Most models qualitatively simulate the observed offshore gradients of SO2, sulfate aerosol, CCN (cloud condensation nuclei) concentration in the MBL as well as differences in concentration between the MBL and the free troposphere. Most models also qualitatively capture the decrease in cloud droplet number away from the coast. However, there are large quantitative intermodel differences in both means and gradients of these quantities. Many models are able to represent episodic offshore increases in cloud droplet number and aerosol concentrations associated with periods of offshore flow. Most models underestimate CCN (at 0.1% supersaturation) in the MBL and free troposphere. The GCMs also have difficulty simulating coastal gradients in CCN and cloud droplet number concentration near the coast. The overall performance of the models demonstrates their potential utility in simulating aerosol–cloud interactions in the MBL, though quantitative estimation of aerosol–cloud interactions and aerosol indirect effects of MBL clouds with these models remains uncertain.« less

  9. Global and regional modeling of clouds and aerosols in the marine boundary layer during VOCALS: the VOCA intercomparison

    SciTech Connect (OSTI)

    Wyant, M. C.; Bretherton, Christopher S.; Wood, Robert; Carmichael, Gregory; Clarke, A. D.; Fast, Jerome D.; George, R.; Gustafson, William I.; Hannay, Cecile; Lauer, Axel; Lin, Yanluan; Morcrette, J. -J.; Mulcahay, Jane; Saide, Pablo; Spak, S. N.; Yang, Qing

    2015-01-01

    A diverse collection of models are used to simulate the marine boundary layer in the southeast Pacific region during the period of the October–November 2008 VOCALS REx (VAMOS Ocean Cloud Atmosphere Land Study Regional Experiment) field campaign. Regional models simulate the period continuously in boundary-forced free-running mode, while global forecast models and GCMs (general circulation models) are run in forecast mode. The models are compared to extensive observations along a line at 20° S extending westward from the South American coast. Most of the models simulate cloud and aerosol characteristics and gradients across the region that are recognizably similar to observations, despite the complex interaction of processes involved in the problem, many of which are parameterized or poorly resolved. Some models simulate the regional low cloud cover well, though many models underestimate MBL (marine boundary layer) depth near the coast. Most models qualitatively simulate the observed offshore gradients of SO2, sulfate aerosol, CCN (cloud condensation nuclei) concentration in the MBL as well as differences in concentration between the MBL and the free troposphere. Most models also qualitatively capture the decrease in cloud droplet number away from the coast. However, there are large quantitative intermodel differences in both means and gradients of these quantities. Many models are able to represent episodic offshore increases in cloud droplet number and aerosol concentrations associated with periods of offshore flow. Most models underestimate CCN (at 0.1% supersaturation) in the MBL and free troposphere. The GCMs also have difficulty simulating coastal gradients in CCN and cloud droplet number concentration near the coast. The overall performance of the models demonstrates their potential utility in simulating aerosol–cloud interactions in the MBL, though quantitative estimation of aerosol–cloud interactions and aerosol indirect effects of MBL clouds with these models remains uncertain.

  10. Gaussian packet prestack depth migration. Part 2: Optimized Gaussian packets

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Gaussian packet prestack depth migration. Part 2: Optimized Gaussian packets V#19;aclav Bucha packet prestack depth migration consists of four basic steps: (a) preparation of a velocity model su to the Gaussian packet prestack depth migration. Keywords Gaussian packets, Gaussian beams, prestack depth

  11. Observations of Secondary Organic Aerosol Production and Soot Aging under Atmospheric Conditions Using a Novel Environmental Aerosol Chamber 

    E-Print Network [OSTI]

    Glen, Crystal

    2012-02-14

    of the processes leading to SOA production under ambient gaseous and particulate concentrations as well as the impact these aerosol types have on climate is poorly understood. Although the majority of atmospheric aerosols scatter radiation either directly...

  12. AEROSOL-PRECIPITATION INTERACTIONS IN THE SOUTHERN APPALACHIAN MOUNTAINS

    E-Print Network [OSTI]

    AEROSOL-PRECIPITATION INTERACTIONS IN THE SOUTHERN APPALACHIAN MOUNTAINS A Thesis by GINGER MARIE of the requirements for the degree of MASTER OF ARTS May 2011 Department of Geography and Planning #12;AEROSOL-PRECIPITATION and Graduate Studies #12;Copyright by Ginger Marie Kelly 2011 All Rights Reserved #12;iv ABSTRACT AEROSOL-PRECIPITATION

  13. Measuring Nighttime Atmospheric Opacity Using Images From the Mars Exploration Rovers 

    E-Print Network [OSTI]

    Bean, Keri M

    2012-07-11

    Atmospheric opacity, otherwise known as optical depth, is the measurement of the amount of radiation reaching the surface through the atmosphere. The spatial and temporal patterns in optical depth tell us about the aerosol and cloud cycles...

  14. Aerodynamic Focusing Of High-Density Aerosols

    SciTech Connect (OSTI)

    Ruiz, D. E.; Fisch, Nathaniel

    2014-02-24

    High-density micron-sized particle aerosols might form the basis for a number of applications in which a material target with a particular shape might be quickly ionized to form a cylindrical or sheet shaped plasma. A simple experimental device was built in order to study the properties of high-density aerosol focusing for 1#22; m silica spheres. Preliminary results recover previous findings on aerodynamic focusing at low densities. At higher densities, it is demonstrated that the focusing properties change in a way which is consistent with a density dependent Stokes number.

  15. Characterization of Ambient Aerosols in Mexico City during the MCMA-2003 Campaign with Aerosol Mass Spectrometry. Results from the CENICA Supersite

    SciTech Connect (OSTI)

    Salcedo, D.; Onasch, Timothy B.; Dzepina, K.; Canagaratna, M. R.; Zhang, Q.; Huffman, A. J.; DeCarlo, Peter; Jayne, J. T.; Mortimer, P.; Worsnop, Douglas R.; Kolb, C. E.; Johnson, Kirsten S.; Zuberi, Bilal M.; Marr, L.; Volkamer, Rainer M.; Molina, Luisa; Molina, Mario J.; Cardenas, B.; Bernabe, R.; Marquez, C.; Gaffney, Jeffrey S.; Marley, Nancy A.; Laskin, Alexander; Shutthanandan, V.; Xie, YuLong; Brune, W. H.; Lesher, R.; Shirley, T.; Jiminez, J. L.

    2006-03-24

    An Aerodyne Aerosol Mass Spectrometer (AMS) was deployed at the CENICA Supersite, while another was deployed in the Aerodyne Mobile Laboratory (AML) during the Mexico City Metropolitan Area field study (MCMA-2003) from March 29-May 4, 2003 to investigate particle concentrations, sources, and processes. This is the first of a series of papers reporting the AMS results from this campaign. The AMS provides real time information on mass concentration and composition of the non-refractory species in particulate matter less than 1 ?m (NR PM1) with high time and size resolution. For the first time, we report field results from a beam width probe, which was used to study the shape and mixing state of the particles and to quantify potential losses of irregular particles due to beam broadening inside the AMS. Data from this probe show that no significant amount of irregular particles was lost due to excessive beam broadening. A comparison of the CENICA and AML AMSs measurements is presented, being the first published intercomparison between two quadrupole AMSs. The speciation, and mass concentrations reported by the two AMSs compared well. In order to account for the refractory material in the aerosol, we also present measurements of Black Carbon (BC) using an aethalometer and an estimate of the aerosol soil component obtained from PIXE analysis of filters. Comparisons of (AMS + BC + soil) mass concentration with other collocated particle instruments (a LASAIR Optical Particle Counter, a Tapered Element Oscillating Microbalance (TEOM) and a DustTrack Aerosol Monitor) are also presented. The comparisons show that the (AMS + BC + soil) mass concentration during MCMC-2003 is a good approximation to the total PM??? mass concentration.

  16. Flattening coefficient of aerosols collected on treated slides 

    E-Print Network [OSTI]

    Olan-Figueroa, Excel

    1981-01-01

    was found to be 1. 338, and for DOP, 1. 354. There is no apparent variation of F with particle diameter for aerosols in the 2. 7-29. 1 um range. The slightly lower value of F for oleic acid suggests that the contact angle of oleic acid with respect... monodisoerse aerosols in the 1. 5 to 50 um diameter range, the vibratino j et monodisperse aerosol generator has been used. The monodisperse aerosols generated by this device can be considered as an "aerosol standard" since the size and concentration...

  17. Near real time vapor detection and enhancement using aerosol adsorption

    DOE Patents [OSTI]

    Novick, V.J.; Johnson, S.A.

    1999-08-03

    A vapor sample detection method is described where the vapor sample contains vapor and ambient air and surrounding natural background particles. The vapor sample detection method includes the steps of generating a supply of aerosol that have a particular effective median particle size, mixing the aerosol with the vapor sample forming aerosol and adsorbed vapor suspended in an air stream, impacting the suspended aerosol and adsorbed vapor upon a reflecting element, alternatively directing infrared light to the impacted aerosol and adsorbed vapor, detecting and analyzing the alternatively directed infrared light in essentially real time using a spectrometer and a microcomputer and identifying the vapor sample. 13 figs.

  18. Organic aerosol components observed in Northern Hemispheric datasets from Aerosol Mass Spectrometry

    E-Print Network [OSTI]

    Kroll, Jesse

    In this study we compile and present results from the factor analysis of 43 Aerosol Mass Spectrometer (AMS) datasets (27 of the datasets are reanalyzed in this work). The components from all sites, when taken together, ...

  19. Effect of Hydrophobic Primary Organic Aerosols on Secondary Organic Aerosol Formation from Ozonolysis of ?-Pinene

    SciTech Connect (OSTI)

    Song, Chen; Zaveri, Rahul A.; Alexander, M. Lizabeth; Thornton, Joel A.; Madronich, Sasha; Ortega, John V.; Zelenyuk, Alla; Yu, Xiao-Ying; Laskin, Alexander; Maughan, A. D.

    2007-10-16

    Semi-empirical secondary organic aerosol (SOA) models typically assume a well-mixed organic aerosol phase even in the presence of hydrophobic primary organic aerosols (POA). This assumption significantly enhances the modeled SOA yields as additional organic mass is made available to absorb greater amounts of oxidized secondary organic gases than otherwise. We investigate the applicability of this critical assumption by measuring SOA yields from ozonolysis of ?-pinene (a major biogenic SOA precursor) in a smog chamber in the absence and in the presence of dioctyl phthalate (DOP) and lubricating oil seed aerosol. These particles serve as surrogates for urban hydrophobic POA. The results show that these POA did not enhance the SOA yields. If these results are found to apply to other biogenic SOA precursors, then the semi-empirical models used in many global models would predict significantly less biogenic SOA mass and display reduced sensitivity to anthropogenic POA emissions than previously thought.

  20. Two Hundred Fifty Years of Aerosols and Climate: The End of the Age of Aerosols

    SciTech Connect (OSTI)

    Smith, Steven J.; Bond, Tami C.

    2014-01-20

    Carbonaceous and sulfur aerosols have a substantial global and regional influence on climate in addition to their impact on health and ecosystems. The magnitude of this influence has changed substantially over the past and is expected to continue to change into the future. An integrated picture of the changing climatic influence of black carbon, organic carbon and sulfate over the period 1850 through 2100, focusing on uncertainty, is presented using updated historical inventories and a coordinated set of emission projections. While aerosols have had a substantial impact on climate over the past century, by the end of the 21st century aerosols will likely be only a minor contributor to radiative forcing due to increases in greenhouse gas forcing and a global decrease in pollutant emissions. This outcome is even more certain under a successful implementation of a policy to limit greenhouse gas emissions as low-carbon energy technologies that do not emit appreciable aerosol or SO2 are deployed.

  1. Optical microspectrometer

    DOE Patents [OSTI]

    Sweatt, William C.; Christenson, Todd R.

    2004-05-25

    An optical microspectrometer comprises a grism to disperse the spectra in a line object. A single optical microspectrometer can be used to sequentially scan a planar object, such as a dye-tagged microchip. Because the optical microspectrometer is very compact, multiple optical microspectrometers can be arrayed to provide simultaneous readout across the width of the planar object The optical microspectrometer can be fabricated with lithographic process, such as deep X-ray lithography (DXRL), with as few as two perpendicular exposures.

  2. Results from simulated upper-plenum aerosol transport and aerosol resuspension experiments

    SciTech Connect (OSTI)

    Wright, A.L.; Pattison, W.L.

    1984-01-01

    Recent calculational results published as part of the Battelle-Columbus BMI-2104 source term study indicate that, for some LWR accident sequences, aerosol deposition in the reactor primary coolant system (PCS) can lead to significant reductions in the radionuclide source term. Aerosol transport and deposition in the PCS have been calculated in this study using the TRAP-MELT 2 computer code, which was developed at Battelle-Columbus; the status of validation of the TRAP-MELT 2 code has been described in an Oak Ridge National Laboratory (ORNL) report. The objective of the ORNL TRAP-MELT Validation Project, which is sponsored by the Fuel Systems Behavior Research Branch of the US Nuclear Regulatory Commission, is to conduct simulated reactor-vessel upper-plenum aerosol deposition and transport tests. The results from these tests will be used in the ongoing effort to validate TRAP-MELT 2. The TRAP-MELT Validation Project includes two experimental subtasks. In the Aerosol Transport Tests, aerosol transport in a vertical pipe is being studied; this geometry was chosen to simulate aerosol deposition and transport in the reactor-vessel upper-plenum. To date, four experiments have been performed; the results from these tests are presented in this paper. 7 refs., 4 figs., 4 tabs.

  3. Generalized methodology for thermal diffusivity depth profile reconstruction in semi-infinite and finitely thick inhomogeneous solids

    E-Print Network [OSTI]

    Mandelis, Andreas

    . The amplitude and phase of the thermal wave generated by an optical or other thermal energy sourceGeneralized methodology for thermal diffusivity depth profile reconstruction in semi, Canada and Manufacturing Research Corporation of Ontario, 1075 North Service Road West, Suite 201

  4. INTRODUCTION Atmospheric aerosol particles influence the Earth's

    E-Print Network [OSTI]

    Wunderle, Stefan

    , scattering, and absorbing solar electromagnetic radiation and by modifying cloud properties due to their roleINTRODUCTION Atmospheric aerosol particles influence the Earth's radiation budget by reflecting to maximum cover a region once in the daytime. In contrary, up-to-date geostationary instruments like

  5. Experimental study of nuclear workplace aerosol samplers 

    E-Print Network [OSTI]

    Parulian, Antony

    1995-01-01

    consists of an inlet-elbow, a transport line, and a EL-900 CAM prototype manufactured by EG&G. Results show that only 12% of 10 []m aerodynamic diameter (AD) aerosol particles penetrate through the complete sampling system when it is operated at flow rate...

  6. A new aerosol collector for quasi on-line analysis of particulate organic matter: the Aerosol Collection Module (ACM) and first applications with a GC/MS-FID

    E-Print Network [OSTI]

    Hohaus, T.

    In many environments organic matter significantly contributes to the composition of atmospheric aerosol particles influencing its properties. Detailed chemical characterization of ambient aerosols is critical in order to ...

  7. Tropical biomass burning smoke plume size, shape, reflectance, and age based on 2001â??2009 MISR imagery of Borneo

    E-Print Network [OSTI]

    Zender, C. S.; Krolewski, A. G.; Tosca, M. G.; Randerson, J. T.

    2012-01-01

    C. S. Zender et al. : Tropical biomass burning smoke plumeslaboratory measurements of biomass-burning emis- sions: 1.aerosol optical depth biomass burning events: a comparison

  8. Tropical biomass burning smoke plume size, shape, reflectance, and age based on 2001-2009 MISR imagery of Borneo

    E-Print Network [OSTI]

    Zender, CS; Krolewski, AG; Tosca, MG; Randerson, JT

    2012-01-01

    C. S. Zender et al. : Tropical biomass burning smoke plumeslaboratory measurements of biomass-burning emis- sions: 1.aerosol optical depth biomass burning events: a comparison

  9. Initial Assessment of the Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR)-Based Aerosol Retrieval: Sensitivity Study

    SciTech Connect (OSTI)

    Kassianov, Evgueni I.; Flynn, Connor J.; Redemann, Jens; Schmid, Beat; Russell, P. B.; Sinyuk, Alexander

    2012-10-24

    The Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) being developed for airborne measurements will offer retrievals of aerosol microphysical and optical properties from multi-angular and multi-spectral measurements of sky radiance and direct-beam sun transmittance. In this study, we assess the expected accuracy of the 4STAR-based aerosol retrieval and its sensitivity to major sources of anticipated perturbations in the 4STAR measurements by adapting a theoretical approach previously developed for the AERONET measurements. The major anticipated perturbations are (1) an apparent enhancement of sky radiance at small scattering angles associated with the necessarily compact design of the 4STAR and (2) and an offset (i.e. uncertainty) of sky radiance calibration independent of scattering angle. The assessment is performed through application of the operational AERONET aerosol retrieval and constructed synthetic 4STAR-like data. Particular attention is given to the impact of these perturbations on the upwelling and downwelling broadband fluxes and the direct aerosol radiative forcing at the bottom and top of the atmosphere. The results from this study suggest that limitations in the accuracy of 4STAR-retrieved particle size distributions and scattering phase functions have diminished impact on the accuracy of retrieved bulk microphysical parameters, permitting quite accurate retrievals of properties including the effective radius (up to 10%, or 0.03), and the radiatively important optical properties, such as the asymmetry factor (up to 4%, or ±0.02) and single-scattering albedo (up to 6%, or ±0.04). Also, the obtained results indicate that the uncertainties in the retrieved aerosol optical properties are quite small in the context of the calculated fluxes and direct aerosol radiative forcing (up to 15%, or 3 Wm-2).

  10. Integrated optical filters using Bragg gratings and resonators

    E-Print Network [OSTI]

    Khan, Mohammad Jalal

    2002-01-01

    This thesis provides an in-depth study of optical filters made using integrated Bragg gratings and Bragg resonators. Various topologies for making add/drop filters using integrated gratings are outlined. Each class of ...

  11. Electro-optical Modulation in Graphene Integrated Photonic Crystal Nanocavities

    E-Print Network [OSTI]

    Gan, Xuetao

    We demonstrate high-contrast electro-optic modulation in a graphene integrated photonic crystal nanocavity, providing a modulation depth of more than 10 dB at telecom wavelengths. This work shows the feasibility of ...

  12. Gulf of Mexico Proved Reserves By Water Depth, 2009

    Gasoline and Diesel Fuel Update (EIA)

    Gulf of Mexico Proved Reserves and Production by Water Depth, 2009 1 Gulf of Mexico Proved Reserves and Production by Water Depth The Gulf of Mexico Federal Offshore region (GOM...

  13. Ocean General Circula-on near 1000 m depth

    E-Print Network [OSTI]

    Lherminier, Pascale

    currents near 1000 m depth · Eddy Kine-c Energy near 1000 m depth · Seasonal hemisphere), Kuroshio, Oyashio, East Kamchatka, Alaska Stream, Gulf Stream, Labrador, East and West Greenland (northern hemisphere). · Alternate zonal bands

  14. Airborne aerosol in situ measurements during TCAP: A closure study of total scattering

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Kassianov, Evgueni; Sedlacek, Arthur; Berg, Larry K.; Pekour, Mikhail; Barnard, James; Chand, Duli; Flynn, Connor; Ovchinnikov, Mikhail; Schmid, Beat; Shilling, John; et al

    2015-07-31

    We present a framework for calculating the total scattering of both non-absorbing and absorbing aerosol at ambient conditions from aircraft data. Our framework is developed emphasizing the explicit use of chemical composition data for estimating the complex refractive index (RI) of particles, and thus obtaining improved ambient size spectra derived from Optical Particle Counter (OPC) measurements. The feasibility of our framework for improved calculations of total scattering is demonstrated using three types of data collected by the U.S. Department of Energy’s (DOE) aircraft during the Two-Column Aerosol Project (TCAP). Namely, these data types are: (1) size distributions measured by amore »suite of OPC’s; (2) chemical composition data measured by an Aerosol Mass Spectrometer and a Single Particle Soot Photometer; and (3) the dry total scattering coefficient measured by a integrating nephelometer and scattering enhancement factor measured with a humidification system. We demonstrate that good agreement (~10%) between the observed and calculated scattering can be obtained under ambient conditions (RH « less

  15. Kirchhoff prestack depth migration in simple models of various anisotropy

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Kirchhoff prestack depth migration in simple models of various anisotropy V´aclav Bucha Department Republic, E-mail: bucha@seis.karlov.mff.cuni.cz Summary We apply the Kirchhoff prestack depth migration anisotropy and monoclinic anisotropy. We test Kirchhoff prestack depth migration in two ways: a

  16. Kirchhoff prestack depth migration in 3-D simple models

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Kirchhoff prestack depth migration in 3-D simple models: comparison of triclinic anisotropy depth migration to calculate migrated sections in 3-D simple anisotropic homogeneous velocity models interface. The anisotropy in the upper layer is triclinic. We apply Kirch- hoff prestack depth migration

  17. Methods Note/ Net Recharge vs. Depth to Groundwater

    E-Print Network [OSTI]

    Szilagyi, Jozsef

    Methods Note/ Net Recharge vs. Depth to Groundwater Relationship in the Platte River Valley rates were correlated with depth to groundwater (d) values in the wide alluvial valley of the Platte soils with a shallow groundwater table. The transition depth (dt) between negative and positive values

  18. The Radiative Role of Free Tropospheric Aerosols and Marine Clouds over the Central North Atlantic

    SciTech Connect (OSTI)

    Mazzoleni, Claudio; Kumar, Sumit; Wright, Kendra; Kramer, Louisa; Mazzoleni, Lynn; Owen, Robert; Helmig, Detlev

    2014-12-09

    The scientific scope of the project was to exploit the unique location of the Pico Mountain Observatory (PMO) located in the summit caldera of the Pico Volcano in Pico Island in the Azores, for atmospheric studies. The observatory, located at 2225m a.s.l., typically samples free tropospheric aerosols laying above the marine low-level clouds and long-range transported from North America. The broad purpose of this research was to provide the scientific community with a better understanding of fundamental physical processes governing the effects of aerosols on radiative forcing and climate; with the ultimate goal of improving our abilities to understand past climate and to predict future changes through numerical models. The project was 'exploratory' in nature, with the plan to demonstrate the feasibility of deploying for the first time, an extensive aerosol research package at PMO. One of the primary activities was to test the deployment of these instruments at the site, to collect data during the 2012 summer season, and to further develop the infrastructure and the knowledge for performing novel research at PMO in follow-up longer-term aerosol-cloud studies. In the future, PMO could provide an elevated research outpost to support the renewed DOE effort in the Azores that was intensified in 2013 with the opening of the new sea-level ARM-DOE Eastern North Atlantic permanent facility at Graciosa Island. During the project period, extensive new data sets were collected for the planned 2012 season. Thanks to other synergistic activities and opportunities, data collection was then successfully extended to 2013 and 2014. Highlights of the scientific findings during this project include: a) biomass burning contribute significantly to the aerosol loading in the North Atlantic free troposphere; however, long-range transported black carbon concentrations decreased substantially in the last decade. b) Single black carbon particles – analyzed off-line at the electron microscope – were often very compacted, suggesting cloud processing and exhibiting different optical properties from fresh emissions. In addition, black carbon was found to be sometimes mixed with mineral dust, affecting its optical properties and potential forcing. c) Some aerosols collected at PMO acted as ice nuclei, potentially contributing to cirrus cloud formation during their transport in the upper free troposphere. Identified good ice nuclei were often mineral dust particles. d) The free tropospheric aerosols studied at PMO have relevance to low level marine clouds due, for example, to synoptic subsidence entraining free tropospheric aerosols into the marine boundary layer. This has potentially large consequences on cloud condensation nuclei concentrations and compositions in the marine boundary layer; therefore, having an effect on the marine stratus clouds, with potentially important repercussions on the radiative forcing. The scientific products of this project currently include contributions to two papers published in the Nature Publishing group (Nature Communications and Scientific Reports), one paper under revision for Atmospheric Chemistry and Physics, one in review in Geophysical Research Letters and one recently submitted to Atmospheric Chemistry and Physics Discussion. In addition, four manuscripts are in advanced state of preparation. Finally, twenty-eight presentations were given at international conferences, workshops and seminars.

  19. Intercomparison and Evaluation of Global Aerosol Microphysical Properties among AeroCom Models of a Range of Complexity

    SciTech Connect (OSTI)

    Mann, G. W.; Carslaw, K. S.; Reddington, C. L.; Pringle, K. J.; Schulz, M.; Asmi, A.; Spracklen, D. V.; Ridley, D. A.; Woodhouse, M. T.; Lee, L. A.; Zhang, Kai; Ghan, Steven J.; Easter, Richard C.; Liu, Xiaohong; Stier, P.; Lee, Y. H.; Adams, P. J.; Tost, H.; Lelieveld, J.; Bauer, S.; Tsigaridis, Kostas; van Noije, T.; Strunk, A.; Vignati, E.; Bellouin, N.; Dalvi, M.; Johnson, C. E.; Bergman, T.; Kokkola, H.; Von Salzen, Knut; Yu, Fangqun; Luo, Gan; Petzold, A.; Heintzenberg, J.; Clarke, A. D.; Ogren, J. A.; Gras, J.; Baltensperger, Urs; Kaminski, U.; Jennings, S. G.; O'Dowd, C. D.; Harrison, R. M.; Beddows, D. C.; Kulmala, M.; Viisanen, Y.; Ulevicius, V.; Mihalopoulos, Nikos; Zdimal, V.; Fiebig, M.; Hansson, H. C.; Swietlicki, E.; Henzing, J. S.

    2014-05-13

    Many of the next generation of global climate models will include aerosol schemes which explicitly simulate the microphysical processes that determine the particle size distribution. These models enable aerosol optical properties and cloud condensation nuclei (CCN) concentrations to be determined by fundamental aerosol processes, which should lead to a more physically based simulation of aerosol direct and indirect radiative forcings. This study examines the global variation in particle size distribution simulated by twelve global aerosol microphysics models to quantify model diversity and to identify any common biases against observations. Evaluation against size distribution measurements from a new European network of aerosol supersites shows that the mean model agrees quite well with the observations at many sites on the annual mean, but there are some seasonal biases common to many sites. In particular, at many of these European sites, the accumulation mode number concentration is biased low during winter and Aitken mode concentrations tend to be overestimated in winter and underestimated in summer. At high northern latitudes, the models strongly underpredict Aitken and accumulation particle concentrations compared to the measurements, consistent with previous studies that have highlighted the poor performance of global aerosol models in the Arctic. In the marine boundary layer, the models capture the observed meridional variation in the size distribution, which is dominated by the Aitken mode at high latitudes, with an increasing concentration of accumulation particles with decreasing latitude. Considering vertical profiles, the models reproduce the observed peak in total particle concentrations in the upper troposphere due to new particle formation, although modelled peak concentrations tend to be biased high over Europe. Overall, the results suggest that most global aerosol microphysics models simulate the global variation of the particle size distribution with a good degree of skill, but some models are in poor agreement with the observations. Further work is required to better constrain size-resolved primary and secondary particle number sources, and an improved understanding of nucleation and growth (e.g. the role of nitrate and secondary organics) will improve the fidelity of simulated particle size distributions.

  20. Total aerosol effect: forcing or radiative flux perturbation?

    SciTech Connect (OSTI)

    Lohmann, Ulrike; Storelvmo, Trude; Jones, Andy; Rotstayn, Leon; Menon, Surabi; Quaas, Johannes; Ekman, Annica; Koch, Dorothy; Ruedy, Reto

    2009-09-25

    Uncertainties in aerosol forcings, especially those associated with clouds, contribute to a large extent to uncertainties in the total anthropogenic forcing. The interaction of aerosols with clouds and radiation introduces feedbacks which can affect the rate of rain formation. Traditionally these feedbacks were not included in estimates of total aerosol forcing. Here we argue that they should be included because these feedbacks act quickly compared with the time scale of global warming. We show that for different forcing agents (aerosols and greenhouse gases) the radiative forcings as traditionally defined agree rather well with estimates from a method, here referred to as radiative flux perturbations (RFP), that takes these fast feedbacks and interactions into account. Thus we propose replacing the direct and indirect aerosol forcing in the IPCC forcing chart with RFP estimates. This implies that it is better to evaluate the total anthropogenic aerosol effect as a whole.

  1. Climate Engineering with Stratospheric Aerosols and Associated Engineering Parameters

    SciTech Connect (OSTI)

    Kravitz, Benjamin S.

    2013-02-12

    Climate engineering with stratospheric aerosols, an idea inspired by large volcaniceruptions, could cool the Earth’s surface and thus alleviate some of the predicted dangerous impacts of anthropogenic climate change. However, the effectiveness of climate engineering to achieve a particular climate goal, and any associated side effects, depend on certain aerosol parameters and how the aerosols are deployed in the stratosphere. Through the examples of sulfate and black carbon aerosols, this paper examines "engineering" parameters-aerosol composition, aerosol size, and spatial and temporal variations in deployment-for stratospheric climate engineering. The effects of climate engineering are sensitive to these parameters, suggesting that a particle could be found ordesigned to achieve specific desired climate outcomes. This prospect opens the possibility for discussion of societal goals for climate engineering.

  2. Design of Aerosol Face Masks for Children Using Computerized 3D Face Analysis

    E-Print Network [OSTI]

    Kimmel, Ron

    seal to the child's face, and thus may minimize aerosol leakage and dead space. Key words: inhaled supplied with valved aerosol hold- ing chambers used for aerosol therapy. (Adapted with per- mission from

  3. Transport and mixing patterns over Central California during the carbonaceous aerosol and radiative effects study (CARES)

    SciTech Connect (OSTI)

    Fast J. D.; Springston S.; Gustafson Jr., W. I.; Berg, L. K.; Shaw, W. J.; Pekour, M.; Shrivastava, M.; Barnard, J. C.; Ferrare, R. A.; Hostetler, C. A.; Hair, J. A.; Erickson, M.; Jobson, B. T.; Flowers, B.; Dubey, M. K.; Pierce, R. B.; Dolislager, L.; Pederson, J.; Zaveri, R. A.

    2012-02-17

    We describe the synoptic and regional-scale meteorological conditions that affected the transport and mixing of trace gases and aerosols in the vicinity of Sacramento, California during June 2010 when the Carbonaceous Aerosol and Radiative Effects Study (CARES) was conducted. The meteorological measurements collected by various instruments deployed during the campaign and the performance of the chemistry version of the Weather Research and Forecasting model (WRF-Chem) are both discussed. WRF-Chem was run daily during the campaign to forecast the spatial and temporal variation of carbon monoxide emitted from 20 anthropogenic source regions in California to guide aircraft sampling. The model is shown to reproduce the overall circulations and boundary-layer characteristics in the region, although errors in the upslope wind speed and boundary-layer depth contribute to differences in the observed and simulated carbon monoxide. Thermally-driven upslope flows that transported pollutants from Sacramento over the foothills of the Sierra Nevada occurred every afternoon, except during three periods when the passage of mid-tropospheric troughs disrupted the regional-scale flow patterns. The meteorological conditions after the passage of the third trough were the most favorable for photochemistry and likely formation of secondary organic aerosols. Meteorological measurements and model forecasts indicate that the Sacramento pollutant plume was likely transported over a downwind site that collected trace gas and aerosol measurements during 23 time periods; however, direct transport occurred during only eight of these periods. The model also showed that emissions from the San Francisco Bay area transported by intrusions of marine air contributed a large fraction of the carbon monoxide in the vicinity of Sacramento, suggesting that this source likely affects local chemistry. Contributions from other sources of pollutants, such as those in the Sacramento Valley and San Joaquin Valley, were relatively low. Aerosol layering in the free troposphere was observed during the morning by an airborne Lidar. WRF-Chem forecasts showed that mountain venting processes contributed to aged pollutants aloft in the valley atmosphere that are then entrained into the growing boundary layer the subsequent day.

  4. Transport and Mixing Patterns over Central California during the Carbonaceous Aerosol and Radiative Effects Study (CARES)

    SciTech Connect (OSTI)

    Fast, Jerome D.; Gustafson, William I.; Berg, Larry K.; Shaw, William J.; Pekour, Mikhail S.; Shrivastava, ManishKumar B.; Barnard, James C.; Ferrare, R.; Hostetler, Chris A.; Hair, John; Erickson, Matthew H.; Jobson, Tom; Flowers, Bradley; Dubey, Manvendra K.; Springston, Stephen R.; Pirce, Bradley R.; Dolislager, Leon; Pederson, J. R.; Zaveri, Rahul A.

    2012-02-17

    We describe the synoptic and regional-scale meteorological conditions that affected the transport and mixing of trace gases and aerosols in the vicinity of Sacramento, California during June 2010 when the Carbonaceous Aerosol and Radiative Effects Study (CARES) was conducted. The meteorological measurements collected by various instruments deployed during the campaign and the performance of the chemistry version of the Weather Research and Forecasting model (WRF-Chem) are both discussed. WRF-Chem was run daily during the campaign to forecast the spatial and temporal variation of carbon monoxide emitted from 20 anthropogenic source regions in California to guide aircraft sampling. The model is shown to reproduce the overall circulations and boundary-layer characteristics in the region, although errors in the upslope wind speed and boundary-layer depth contribute to differences in the observed and simulated carbon monoxide. Thermally-driven upslope flows that transported pollutants from Sacramento over the foothills of the Sierra Nevada occurred every afternoon, except during three periods when the passage of mid-tropospheric troughs disrupted the regional-scales flow patterns. The meteorological conditions after the passage of the third trough were the most favorable for photochemistry and likely formation of secondary organic aerosols. Meteorological measurements and model forecasts indicate that the Sacramento pollutant plume was likely transported over a downwind site that collected trace gas and aerosol measurements during 23 periods; however, direct transport occurred during only eight of these periods. The model also showed that emissions from the San Francisco Bay area transported by intrusions of marine air contributed a large fraction of the carbon monoxide in the vicinity of Sacramento, suggesting that this source likely affects local chemistry. Contributions from other sources of pollutants, such as those in the Sacramento Valley and San Joaquin Valley, were relatively low. Aerosol layering in the free troposphere was observed during the morning by an airborne Lidar; WRF-Chem forecasts showed that mountain venting processes contributed to aged pollutants aloft in the valley atmosphere which then can be entrained into the growing boundary layer the subsequent day.

  5. Formation mechanisms and quantification of organic nitrates in atmospheric aerosol

    E-Print Network [OSTI]

    Rollins, Andrew Waite

    2010-01-01

    and J. Viidanoja, Atmospheric chemistry of c 3 -c 6organic nitrates, Atmospheric Chemistry and Physics, 9 (4),organic aerosol yields, Atmospheric Chemistry and Physics

  6. Challenge the future 1 Observations of aerosol-cloud-radiation

    E-Print Network [OSTI]

    Graaf, Martin de

    -road Industrial coal Residential solid fuel Biofuel cooking Biofuel heating Coal Open Burning Agricultural fields causes Differences in: · cloud properties · cloud fraction and location · aerosol properties · smoke

  7. Extending the physicochemical characterization of aerosol particles in California

    E-Print Network [OSTI]

    Zauscher, Melanie Dorothy

    2012-01-01

    W. T. (1997).Emissions from Smoldering Combustion of BiomassCombustion generated aerosols, including emissions from diesel and gasoline engines, biomass and

  8. Climatic effects of different aerosol types in China simulated

    E-Print Network [OSTI]

    Y. GU

    2006-01-01

    P. Shettle (1991), Atmospheric Aero- sols—Global ClimatologyEffects of stratospheric aero- sols and preliminarytypes, such as volcanic aero- sols, desert aerosols, or

  9. Relating Secondary Organic Aerosol Characteristics with Cloud Condensation Nuclei Activity

    E-Print Network [OSTI]

    Tang, Xiaochen

    2013-01-01

    by V and Ni from heavy oil combustion: Anthropogenic sourcesgeneration from heavy fuel oil (HFO) as an alternative toengines operating with heavy fuel oils. Journal of Aerosol

  10. The Radiative Role of Free Tropospheric Aerosols and Marine Clouds...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: The Radiative Role of Free Tropospheric Aerosols and Marine Clouds over the Central North Atlantic Citation Details In-Document Search Title: The Radiative Role...

  11. Absorbing Aerosol Index (AAI) The residue method for the detection of aerosols

    E-Print Network [OSTI]

    Graaf, Martin de

    and calculation Main sensitivities of residue Problems with the residue Conclusions and outlook #12;#12;o = 380 scattering and absorption #12;#12;#12;Nadir View Solar zenith angle = 45o Residue = 3.5 Rayleigh atmosphere View Solar zenith angle = 45o Residue = -1.0 Rayleigh atmosphere, As = 0.16 Scattering aerosol layer

  12. AEROSOL CHEMICAL COMPOSITION CHARACTERIZATION AT THE ARM SOUTHERN GREAT PLAINS (SGP) SITE USING AN AEROSOL CHEMICAL

    E-Print Network [OSTI]

    ) was integrated into the Aerosol Observing System (AOS) at the Atmospheric Radiation Measurement (ARM) SGP site in Oklahoma in Nov 2010. This instrument has been measuring concentrations of sulfate, ammonium, nitrate of oxygenated OA with minor contributions from hydrocarbon-like OA, indicating that the OA at the SGP site

  13. Aerosol Science and Technology, 39:6883, 2005 Copyright c American Association for Aerosol Research

    E-Print Network [OSTI]

    . Coffman5 1 Finnish Meteorological Institute, Air Quality Research, Sahaajankatu, Helsinki, Finland 2¨ais¨al¨a Foundation (Finland), and the 100th Anniversary Foundation of Helsingin Sanomat (Finland). Address, 00880 Helsinki, Finland. E-mail: aki.virkkula@fmi.fi properties of aerosols depend on the wavelength

  14. Aerosol Science and Technology, 38:555573, 2004 Copyright c American Association for Aerosol Research

    E-Print Network [OSTI]

    Jimenez, Jose-Luis

    from motor vehicles are a significant source of fine particulate matter (PM) and gaseous pollutants of their emission. This work uses an Aero- dyne aerosol mass spectrometer (AMS) to provide size instrumentation, was deployed on the Aero- dyne Research Inc. (ARI) mobile laboratory, which was used to "chase

  15. Techniques for Minimizing Aerosols (aerosols are a common source of laboratoryacquired infections)

    E-Print Network [OSTI]

    Chan, Hue Sun

    " pipettes to avoid blowing out the last drop Drain pipettes gently with the tip against the inner wall glass rod to crack the glass, allow time for air to seep into the ampoule and gently remove the top than glass (less likely to break which generates aerosols) Source: Adapted from

  16. Role of ammonia chemistry and coarse mode aerosols in global climatological inorganic aerosol distributions

    E-Print Network [OSTI]

    Moore, Keith

    , the aerosolassociated water depends on the composition of the #12;3 particles, which is determined by gas in a three dimensional chemical transport model to understand the roles of ammonia chemistry and natural precursors among modeled aerosol species selfconsistently with ambient relative humidity and natural

  17. Aerosol Science and Technology, 43:486501, 2009 Copyright American Association for Aerosol Research

    E-Print Network [OSTI]

    a NOAA research vessel during the Texas Air Quality Study 2006/Gulf of Mexico Atmospheric Composition for glutaric acid in mixed glutaric acid/NH4HSO4 test aerosols was 0.22 ng collected mass, which corresponds min­1. During TexAQS 2006/GoMACCS, signals well above the detection limit were observed at a number

  18. Control Systems Cyber Security: Defense in Depth Strategies ...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Cyber Security: Defense in Depth Strategies More Documents & Publications Good Practice Guide on Firewall Deployment for SCADA and Process Control Networks Mitigations for...

  19. Bouguer gravity anomalies, depth to bedrock, and shallow temperature...

    Open Energy Info (EERE)

    Bouguer gravity anomalies, depth to bedrock, and shallow temperature in the Humboldt House geothermal area, Pershing County, Nevada Jump to: navigation, search OpenEI Reference...

  20. SCIAMACHY'S ABSORBING AEROSOL INDEX AND THE CONSEQUENCES OF INSTRUMENT DEGRADATION

    E-Print Network [OSTI]

    Graaf, Martin de

    SCIAMACHY'S ABSORBING AEROSOL INDEX AND THE CONSEQUENCES OF INSTRUMENT DEGRADATION L. G. Tilstra1- itoring the Absorbing Aerosol Index (AAI) [1] measured by the satellite instrument SCIAMACHY [2]. We find. This we conclude from straightforward calculation of the effect of instrument degradation based

  1. Global observations of desert dust and biomass burning aerosols

    E-Print Network [OSTI]

    Graaf, Martin de

    and desert dust observations from GOME and SCIAMACHY · Conclusions and Outlook #12; · Absorbing Aerosol Transfer Model Solar zenith angle = 30° Viewing zenith angle = 0° Surface albedo = 5% #12;Reflectance at TOA with absorbing aerosols Doubling-Adding KNMI Radiative Transfer Model Solar zenith angle = 30

  2. Organic Aerosol Formation Downwind from the Deepwater Horizon Oil Spill

    E-Print Network [OSTI]

    Toohey, Darin W.

    Organic Aerosol Formation Downwind from the Deepwater Horizon Oil Spill Nicole ONeill - ATOC 3500 and aerosol composition of air over the Deepwater Horizon oil spill in the Gulf of Mexico. · The lightest chemicals in the oil evaporated within hours, as scientists expected them to do. What they didn't expect

  3. Carbonaceous aerosol particles from common vegetation in the Grand Canyon

    SciTech Connect (OSTI)

    Hallock, K.A.; Mazurek, M.A. (Brookhaven National Lab., Upton, NY (United States)); Cass, G.R. (California Inst. of Tech., Pasadena, CA (United States). Dept. of Environmental Engineering Science)

    1992-05-01

    The problem of visibility reduction in the Grand Canyon due to fine organic aerosol particles in the atmosphere has become an area of increased environmental concern. Aerosol particles can be derived from many emission sources. In this report, we focus on identifying organic aerosols derived from common vegetation in the Grand Canyon. These aerosols are expected to be significant contributors to the total atmospheric organic aerosol content. Aerosol samples from living vegetation were collected by resuspension of surface wax and resin components liberated from the leaves of vegetation common to areas of the Grand Canyon. The samples were analyzed using high-resolution gas chromatography/mass spectrometry (GC/MS). Probable identification of compounds was made by comparison of sample spectra with National Institute of Standards and Technology (NIST) mass spectral references and positive identification of compounds was made when possible by comparison with authentic standards as well as NIST references. Using these references, we have been able to positively identify the presence of n-alkane and n-alkanoic acid homolog series in the surface waxes of the vegetation sampled. Several monoterpenes, sesquiterpenes, and diterpenes were identified also as possible biogenic aerosols which may contribute to the total organic aerosol abundance leading to visibility reduction in the Grand Canyon.

  4. Supplementary Material1 Characterization of Organic Aerosol Produced during2

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    mass spectra of a dominant type (coal) of ambient aerosol in Shanghai using2 ATOFMS (m/z from 1501 Supplementary Material1 Characterization of Organic Aerosol Produced during2 Pulverized Coal diagram of combustion process of a single coal particle5 6 #12;3 10 100 10 3 10 4 10 5 Oxygen/coal ratio

  5. Effects of operating conditions on a heat transfer fluid aerosol 

    E-Print Network [OSTI]

    Sukmarg, Passaporn

    2000-01-01

    fluids are used as hot liquids at elevated pressures. If loss of containment does occur, the liquid will leak under pressure and may disperse as a fine aerosol mist. Though it has been recognized that aerosol mists can explode, very little is known about...

  6. Effects of aerosols on deep convective cumulus clouds 

    E-Print Network [OSTI]

    Fan, Jiwen

    2009-05-15

    in the droplet size. Ice processes are more sensitive to the changes of aerosol chemical properties than the warm rain processes. The most noticeable effect of increasing aerosol number concentrations is an increase of CDNC and cloud water content but a decrease...

  7. Flood or Drought: How Do Aerosols Affect Precipitation?

    E-Print Network [OSTI]

    Daniel, Rosenfeld

    Flood or Drought: How Do Aerosols Affect Precipitation? Daniel Rosenfeld,1 * Ulrike Lohmann,2 and the initiation of precipitation. Large concentrations of human-made aerosols have been reported to both decrease hand, heavily polluted clouds evaporate much of their water before precipitation can occur, if they can

  8. Study of Aerosol Indirect Effects in China

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effect PhotovoltaicsStructure andChallenge | Department,Aerosol Indirect Effects in

  9. Chemical distribution in high-solids paint overspray aerosols

    SciTech Connect (OSTI)

    D'Arcy, J.B.; Chan, T.L. )

    1990-03-01

    The chemical composition of high-solids basecoat paint overspray aerosols was determined as a function of particle size. Detailed information on the chemical composition of the overspray aerosols is important in health hazard evaluation since the composition and distribution within the airborne particles may differ significantly from the bulk paint material. This study was conducted in a typical down-draft paint booth equipped with air-atomized spray painting equipment. A fixed paint target was used to simulate typical overspray generation conditions and the aerosols were collected isokinetically with a seven-stage cascade impactor for size-fractionated analysis. The overspray aerosol from six paints consisted of organic paint binders with varying amounts of inorganic species as pigments or luster enhancers. These overspray aerosols had mass median aerodynamic diameters (MMAD) ranging from 2.9 to 9.7 microns. The size-fractionated paint samples collected on the impaction stages were analyzed by energy dispersive X-ray spectrometry on a scanning electron microscope (SEM-EDXRS) to identify the metallic elements. Atomic absorption spectrometry was used to determine the mass distribution of aluminum and iron as indicators of nonuniform distribution. Three of the aerosols containing aluminum were found to have bimodal distributions with most aluminum distributions having cumulative MMADs larger than the total aerosol. Iron in the aerosols was bimodal for three of the paints with all samples having an overall iron MMAD less than or equal to the overspray aerosol MMAD. Analysis using ultraviolet spectrometry revealed that the organic compounds present in the size-fractionated particulate samples consisted of a single, polydispersed mode with an MMAD similar to that of the total overspray aerosol.

  10. Seasonal and diurnal variations of submicron organic aerosol in Tokyo observed using the Aerodyne aerosol mass spectrometer

    E-Print Network [OSTI]

    Jimenez, Jose-Luis

    with carbon monoxide (CO) and fragments of aliphatic and oxygenated organic compounds in the AMS mass spectra. Combustion-related organic aerosol (combustion OA) is defined as the primary organic aerosol (POA) fraction the combustion OA and the background OA from the total OA. The combustion OA and excess OA show good correlation

  11. Effects of particle size and velocity on burial depth of airborne particles in glass fiber filters

    SciTech Connect (OSTI)

    Higby, D.P.

    1984-11-01

    Air sampling for particulate radioactive material involves collecting airborne particles on a filter and then determining the amount of radioactivity collected per unit volume of air drawn through the filter. The amount of radioactivity collected is frequently determined by directly measuring the radiation emitted from the particles collected on the filter. Counting losses caused by the particle becoming buried in the filter matrix may cause concentrations of airborne particulate radioactive materials to be underestimated by as much as 50%. Furthermore, the dose calculation for inhaled radionuclides will also be affected. The present study was designed to evaluate the extent to which particle size and sampling velocity influence burial depth in glass-fiber filters. Aerosols of high-fired /sup 239/PuO/sub 2/ were collected at various sampling velocities on glass-fiber filters. The fraction of alpha counts lost due to burial was determined as the ratio of activity detected by direct alpha count to the quantity determined by photon spectrometry. The results show that burial of airborne particles collected on glass-fiber filters appears to be a weak function of sampling velocity and particle size. Counting losses ranged from 0 to 25%. A correction that assumes losses of 10 to 15% would ensure that the concentration of airborne alpha-emitting radionuclides would not be underestimated when glass-fiber filters are used. 32 references, 21 figures, 11 tables.

  12. Real Time Head Pose Estimation from Consumer Depth Cameras

    E-Print Network [OSTI]

    Wolberg, George

    for estimating location and orientation of a person's head, from depth data acquired by a low quality device. OurReal Time Head Pose Estimation from Consumer Depth Cameras Gabriele Fanelli1 , Thibaut Weise2 and the variance of the head position and orientation. We evaluate three different approaches to jointly take

  13. Instrument for Determining Depth of Dehydration of Frozen Fish

    E-Print Network [OSTI]

    . This report describes the design, construction, and operation of a de- hydration depth gauge to measure the degree of dehydration in frozen seafoods. Design The dehydration depth gauge adopts the principle was modified by using a heavier gauge blade having a narrow cutting edge extending I mm below the plane's flat

  14. Electrode immersion depth determination and control in electroslag remelting furnace

    DOE Patents [OSTI]

    Melgaard, David K. (Albuquerque, NM); Beaman, Joseph J. (Austin, TX); Shelmidine, Gregory J. (Tijeras, NM)

    2007-02-20

    An apparatus and method for controlling an electroslag remelting furnace comprising adjusting electrode drive speed by an amount proportional to a difference between a metric of electrode immersion and a set point, monitoring impedance or voltage, and calculating the metric of electrode immersion depth based upon a predetermined characterization of electrode immersion depth as a function of impedance or voltage.

  15. Imaging wave-penetrable objects in a finite depth ocean

    E-Print Network [OSTI]

    Zou, Jun

    Imaging wave-penetrable objects in a finite depth ocean Keji Liu Yongzhi Xu Jun Zou Abstract. We- penetrable inhomogeneous medium in a 3D finite depth ocean. The method is based on a scat- tering analysis extend the direct sampling method proposed in [13] to image a wave- penetrable inhomogeneous medium

  16. ARM: 10-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Newsom, Rob; Goldsmith, John

    1998-03-01

    10-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  17. ARM: 1-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    2004-10-01

    1-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  18. ARM: 2-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    2004-10-01

    2-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  19. ARM: 10-second Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    2004-10-01

    10-second Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  20. Investigation of Aerosol Sources, Lifetime and Radiative Forcing through Multi-Instrument Data Assimilation

    E-Print Network [OSTI]

    Rubin, Juli Irene

    2012-01-01

    of the various radiative mechanims associated with aerosolof the various radiative mechanims associated with aerosol

  1. Analysis of reflectance spectra of UV-absorbing aerosol scenes measured by SCIAMACHY

    E-Print Network [OSTI]

    Graaf, Martin de

    Analysis of reflectance spectra of UV-absorbing aerosol scenes measured by SCIAMACHY M. de Graaf,1 of reflectance spectra of UV-absorbing aerosol scenes measured by SCIAMACHY, J. Geophys. Res., 112, D02206, doi aerosol (DDA) and biomass burning aerosol (BBA) scenes over oceans are presented, measured by the space

  2. UNDERSTANDING THE INFLUENCES OF ATMOSPHERIC AEROSOLS ON CLIMATE AND CLIMATE CHANGE

    E-Print Network [OSTI]

    Schwartz, Stephen E.

    remarks #12;DMS #12;AEROSOL IN MEXICO CITY BASIN #12;AEROSOL IN MEXICO CITY BASIN Light scattering by aerosols decreases absorption of solar radiation. #12;AEROSOLS AS SEEN FROM SPACE Fire plumes from southern Mexico transported north into Gulf of Mexico. #12;CLOUD BRIGHTENING BY SHIP TRACKS Satellite photo off

  3. Satellite observations of the seasonal cycles of absorbing aerosols in Africa

    E-Print Network [OSTI]

    Graaf, Martin de

    Satellite observations of the seasonal cycles of absorbing aerosols in Africa related to monsoon of aerosol emissions from the wet surface. 1. Introduction The main aerosol types occurring over Africa Africa can be characterized using Absorbing Aerosol Index (AAI) data from Global Ozone Monitoring

  4. ARM: 10-second Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    10-second Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  5. ARM: 10-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    10-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  6. ARM: 2-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    2-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  7. ARM: 1-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    1-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  8. CARES Helps Explain Secondary Organic Aerosols

    ScienceCinema (OSTI)

    Zaveri, Rahul

    2014-06-02

    What happens when urban man-made pollution mixes with what we think of as pristine forest air? To know more about what this interaction means for the climate, the Carbonaceous Aerosol and Radiative Effects Study, or CARES, field campaign was designed in 2010. The sampling strategy during CARES was coordinated with CalNex 2010, another major field campaign that was planned in California in 2010 by the California Air Resources Board (CARB), the National Oceanic and Atmospheric Administration (NOAA), and the California Energy Commission (CEC). "We found two things. When urban pollution mixes with forest pollutions we get more secondary organic aerosols," said Rahul Zaveri, FCSD scientist and project lead on CARES. "SOAs are thought to be formed primarily from forest emissions but only when they interact with urban emissions. The data is saying that there will be climate cooling over the central California valley because of these interactions." Knowledge gained from detailed analyses of data gathered during the CARES campaign, together with laboratory experiments, is being used to improve existing climate models.

  9. Asthmatic responses to airborne acid aerosols

    SciTech Connect (OSTI)

    Ostro, B.D.; Lipsett, M.J.; Wiener, M.B.; Selner, J.C. )

    1991-06-01

    Controlled exposure studies suggest that asthmatics may be more sensitive to the respiratory effects of acidic aerosols than individuals without asthma. This study investigates whether acidic aerosols and other air pollutants are associated with respiratory symptoms in free-living asthmatics. Daily concentrations of hydrogen ion (H+), nitric acid, fine particulates, sulfates and nitrates were obtained during an intensive air monitoring effort in Denver, Colorado, in the winter of 1987-88. A panel of 207 asthmatics recorded respiratory symptoms, frequency of medication use, and related information in daily diaries. We used a multiple regression time-series model to analyze which air pollutants, if any, were associated with health outcomes reported by study participants. Airborne H+ was found to be significantly associated with several indicators of asthma status, including moderate or severe cough and shortness of breath. Cough was also associated with fine particulates, and shortness of breath with sulfates. Incorporating the participants' time spent outside and exercise intensity into the daily measure of exposure strengthened the association between these pollutants and asthmatic symptoms. Nitric acid and nitrates were not significantly associated with any respiratory symptom analyzed. In this population of asthmatics, several outdoor air pollutants, particularly airborne acidity, were associated with daily respiratory symptoms.

  10. CARES Helps Explain Secondary Organic Aerosols

    SciTech Connect (OSTI)

    Zaveri, Rahul

    2014-03-28

    What happens when urban man-made pollution mixes with what we think of as pristine forest air? To know more about what this interaction means for the climate, the Carbonaceous Aerosol and Radiative Effects Study, or CARES, field campaign was designed in 2010. The sampling strategy during CARES was coordinated with CalNex 2010, another major field campaign that was planned in California in 2010 by the California Air Resources Board (CARB), the National Oceanic and Atmospheric Administration (NOAA), and the California Energy Commission (CEC). "We found two things. When urban pollution mixes with forest pollutions we get more secondary organic aerosols," said Rahul Zaveri, FCSD scientist and project lead on CARES. "SOAs are thought to be formed primarily from forest emissions but only when they interact with urban emissions. The data is saying that there will be climate cooling over the central California valley because of these interactions." Knowledge gained from detailed analyses of data gathered during the CARES campaign, together with laboratory experiments, is being used to improve existing climate models.

  11. ENCAPSULATION EFFECTS ON CARBONACEOUS AEROSOL LIGHT ABSORPTION

    E-Print Network [OSTI]

    of interest, soot, exhibits complex aging behavior that alters its optical properties. The consequences, wood-burning kitchen stoves, and coal-fired power plants) will increase black carbon (BC) radiative optical properties on particle mixing state and aggregate morphology, each of which changes

  12. Optical detection dental disease using polarized light

    DOE Patents [OSTI]

    Everett, Matthew J. (Livermore, CA); Colston, Jr., Billy W. (Livermore, CA); Sathyam, Ujwal S. (Livermore, CA); Da Silva, Luiz B. (Danville, CA); Fried, Daniel (San Francisco, CA)

    2003-01-01

    A polarization sensitive optical imaging system is used to detect changes in polarization in dental tissues to aid the diagnosis of dental disease such as caries. The degree of depolarization is measured by illuminating the dental tissue with polarized light and measuring the polarization state of the backscattered light. The polarization state of this reflected light is analyzed using optical polarimetric imaging techniques. A hand-held fiber optic dental probe is used in vivo to direct the incident beam to the dental tissue and collect the reflected light. To provide depth-resolved characterization of the dental tissue, the polarization diagnostics may be incorporated into optical coherence domain reflectometry and optical coherence tomography (OCDR/OCT) systems, which enables identification of subsurface depolarization sites associated with demineralization of enamel or bone.

  13. A five year global aerosol and cloud properties database from ATSR-2 data1 1 1 1 2 3

    E-Print Network [OSTI]

    Oxford, University of

    angle !Satellite zenith angle !Relative (satellite to Sun) azimuth angle !Value of the cost function !Cloud optical depth 1 !Cloud droplet effective radius 1 !Cloud top temperature 1 !Cloud top pressure 1 provides uncertainty estimates, and level 3 data provides variances, for all relevant parameters. Contact

  14. Fire aerosol experiment and comparisons with computer code predictions

    SciTech Connect (OSTI)

    Gregory, W.S.; Nichols, B.D.; White, B.W.; Smith, P.R.; Leslie, I.H.; Corkran, J.R.

    1988-01-01

    Los Alamos National Laboratory, in cooperation with New Mexico State University, has carried on a series of tests to provide experimental data on fire-generated aerosol transport. These data will be used to verify the aerosol transport capabilities of the FIRAC computer code. FIRAC was developed by Los Alamos for the US Nuclear Regulatory Commission. It is intended to be used by safety analysts to evaluate the effects of hypothetical fires on nuclear plants. One of the most significant aspects of this analysis deals with smoke and radioactive material movement throughout the plant. The tests have been carried out using an industrial furnace that can generate gas temperatures to 300/degree/C. To date, we have used quartz aerosol with a median diameter of about 10 ..mu..m as the fire aerosol simulant. We also plan to use fire-generated aerosols of polystyrene and polymethyl methacrylate (PMMA). The test variables include two nominal gas flow rates (150 and 300 ft/sup 3//min) and three nominal gas temperatures (ambient, 150/degree/C, and 300/degree/C). The test results are presented in the form of plots of aerosol deposition vs length of duct. In addition, the mass of aerosol caught in a high-efficiency particulate air (HEPA) filter during the tests is reported. The tests are simulated with the FIRAC code, and the results are compared with the experimental data. 3 refs., 10 figs., 1 tab.

  15. Implementing marine organic aerosols into the GEOS-Chem model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gantt, B.; Johnson, M. S.; Crippa, M.; Prévôt, A. S. H.; Meskhidze, N.

    2015-03-17

    Marine-sourced organic aerosols (MOAs) have been shown to play an important role in tropospheric chemistry by impacting surface mass, cloud condensation nuclei, and ice nuclei concentrations over remote marine and coastal regions. In this work, an online marine primary organic aerosol emission parameterization, designed to be used for both global and regional models, was implemented into the GEOS-Chem (Global Earth Observing System Chemistry) model. The implemented emission scheme improved the large underprediction of organic aerosol concentrations in clean marine regions (normalized mean bias decreases from -79% when using the default settings to -12% when marine organic aerosols are added). Modelmore »predictions were also in good agreement (correlation coefficient of 0.62 and normalized mean bias of -36%) with hourly surface concentrations of MOAs observed during the summertime at an inland site near Paris, France. Our study shows that MOAs have weaker coastal-to-inland concentration gradients than sea-salt aerosols, leading to several inland European cities having >10% of their surface submicron organic aerosol mass concentration with a marine source. The addition of MOA tracers to GEOS-Chem enabled us to identify the regions with large contributions of freshly emitted or aged aerosol having distinct physicochemical properties, potentially indicating optimal locations for future field studies.« less

  16. Implementing marine organic aerosols into the GEOS-Chem model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gantt, B.; Johnson, M. S.; Crippa, M.; Prévôt, A. S. H.; Meskhidze, N.

    2014-09-09

    Marine organic aerosols (MOA) have been shown to play an important role in tropospheric chemistry by impacting surface mass, cloud condensation nuclei, and ice nuclei concentrations over remote marine and coastal regions. In this work, an online marine primary organic aerosol emission parameterization, designed to be used for both global and regional models, was implemented into the GEOS-Chem model. The implemented emission scheme improved the large underprediction of organic aerosol concentrations in clean marine regions (normalized mean bias decreases from -79% when using the default settings to -12% when marine organic aerosols are added). Model predictions were also in goodmore »agreement (correlation coefficient of 0.62 and normalized mean bias of -36%) with hourly surface concentrations of MOA observed during the summertime at an inland site near Paris, France. Our study shows that MOA have weaker coastal-to-inland concentration gradients than sea-salt aerosols, leading to several inland European cities having > 10% of their surface submicron organic aerosol mass concentration with a marine source. The addition of MOA tracers to GEOS-Chem enabled us to identify the regions with large contributions of freshly-emitted or aged aerosol having distinct physicochemical properties, potentially indicating optimal locations for future field studies.« less

  17. Inverse modelling of cloud-aerosol interactions - Part 2: Sensitivity tests on liquid phase clouds using a Markov chain Monte Carlo based simulation approach

    E-Print Network [OSTI]

    Partridge, D. G; Vrugt, J. A; Tunved, P.; Ekman, A. M. L; Struthers, H.; Sorooshian, A.

    2012-01-01

    Seinfeld, J. H. : Aerosol, cloud drop concentration closureof aerosol composition on cloud droplet size distribution –aerosol properties on warm cloud droplet activation, At-

  18. Fiber Optics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    said Todd Eckman, vice president of Information Management for MSA. "This new fiber optics will benefit DOE, Benton PUD and NoaNet (Northwest Open Access Network) users. This,...

  19. Aerosol penetration through a seismically loaded shear wall

    SciTech Connect (OSTI)

    Farrar, C.R.; Girrens, S.P.

    1992-05-01

    An experimental study was performed to measure the aerosol penetration through a reinforced concrete shear wall after simulated seismic damage. Static load-cycle testing, to stress levels sufficient to induce visible shear cracking, was used to simulate the earthquake loading. Air permeability tests were performed both before and after the simulated seismic loading damaged the structure. Aerosol penetration measurements were conducted on the cracked shear wall structure using 0.10 {mu}m monodisperse particles. The measured aerosol number penetration through the cracked shear wall was 0.5%. 7 refs.

  20. Aerosol penetration through a seismically loaded shear wall

    SciTech Connect (OSTI)

    Farrar, C.R.; Girrens, S.P.

    1992-01-01

    An experimental study was performed to measure the aerosol penetration through a reinforced concrete shear wall after simulated seismic damage. Static load-cycle testing, to stress levels sufficient to induce visible shear cracking, was used to simulate the earthquake loading. Air permeability tests were performed both before and after the simulated seismic loading damaged the structure. Aerosol penetration measurements were conducted on the cracked shear wall structure using 0.10 {mu}m monodisperse particles. The measured aerosol number penetration through the cracked shear wall was 0.5%. 7 refs.

  1. Aerosol source term in high pressure melt ejection

    SciTech Connect (OSTI)

    Brockmann, J.E.; Tarbell, W.W.

    1984-11-01

    Pressurized ejection of melt from a reactor pressure vessel has been identified as an important element of a severe reactor accident. Copious aerosol production is observed when thermitically generated melts pressurized with nitrogen or carbon dioxide to 1.3 to 17 MPa are ejected into an air atmosphere. Aerosol particle size distributions measured in the tests have modes of about 0.5, 5, and > 10 ..mu..m. Mechanisms leading to formation of these multimodal size distributions are suggested. This aerosol is a potentially important fission product source term that has not been considered in previous severe accident analyses.

  2. Mexico City Aerosol Analysis During Milagro Using High Resolution Aerosol Mass Spectrometry at the Urban Supersite (T0) - Part 1: Fine Particle Composition and Organic Source Apportionment.

    E-Print Network [OSTI]

    Aiken, A. C.

    Submicron aerosol was analyzed during the MILAGRO field campaign in March 2006 at the T0 urban supersite in Mexico City with a High-Resolution Aerosol Mass Spectrometer (AMS) and complementary instrumentation. Positive ...

  3. Stress map for ion irradiation: Depth-resolved dynamic competition between radiation-induced viscoelastic phenomena in SiO2

    E-Print Network [OSTI]

    Polman, Albert

    doping technology in integrated circuit manufacturing and is used to locally modify and tailor optical of the highly anisotropic ion-induced thermal spike, causes anisotropic strain that freezes in as the thermal or electronic energy loss (stopping), which are both highly depth dependent. In this letter we evaluate

  4. Comparison of Cloud Top Height and Optical Depth Histograms from ISCCP,

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit the following commentsMethods for Estimating Short-Term Extremeposter,MISR,

  5. A Comparison of Cirrus Cloud Visible Optical Depth Derived from Lidar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach HomeA Better Anode Design to Improve Lithium-Ion Batteries Print Lithium-ion batteries arePlasmaARM

  6. ARM - Evaluation Product - MicroPulse LIDAR Cloud Optical Depth (MPLCOD)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Comments? WeDatastreamstps DocumentationAtlanticENA Contacts ENAProductsHSRL

  7. Selective light sintering of Aerosol-Jet printed silver nanoparticle inks on polymer substrates

    SciTech Connect (OSTI)

    Schuetz, K., E-mail: klaus.schuetz1@gmx.de, E-mail: hoerber@faps.uni-erlangen.de, E-mail: franke@faps.uni-erlangen.de; Hoerber, J., E-mail: klaus.schuetz1@gmx.de, E-mail: hoerber@faps.uni-erlangen.de, E-mail: franke@faps.uni-erlangen.de; Franke, J., E-mail: klaus.schuetz1@gmx.de, E-mail: hoerber@faps.uni-erlangen.de, E-mail: franke@faps.uni-erlangen.de [Institute for Factory Automation and Production Systems, University of Erlangen-Nuremberg (Germany)

    2014-05-15

    Printing silver nanoparticle inks to generate conductive structures for electronics on polymer substrates has gained increasing relevance in recent years. In this context, the Aerosol-Jet Technology is well suited to print silver ink on 3D-Molded Interconnect Devices (MID). The deposited ink requires thermal post-treatment to obtain sufficient electrical conductivity and adhesion. However, commonly used oven sintering cannot be applied for many thermoplastic substrates due to low melting temperatures. In this study a new sintering technology, selective light sintering, is presented, based on the focused, continuous light beam of a xenon lamp. Sintering experiments were conducted with Aerosol-Jet printed structures on various polycarbonate (PC) substrates. Especially on neat, light transparent PC, silver tracks were evenly sintered with marginal impact to the substrate. Electrical conductivities significantly exceed the values obtained with conventional oven sintering. Adhesive strength is sufficient for conductive tracks. Experiments with non-transparent PC substrates led to substrate damage due to increased light absorption. Therefore a concept for a variation of light sintering was developed, using optical filters. First experiments showed significant reduction of substrate damage and good sintering qualities. The highly promising results of the conducted experiments provide a base for further investigations to increase adhesion and qualifying the technology for MID applications and a broad spectrum of thermoplastic substrates.

  8. Diesel Aerosol Sampling in the Atmosphere

    SciTech Connect (OSTI)

    David Kittelson; Jason Johnson; Winthrop Watts; Qiang Wei; Marcus Drayton; Dwane Paulsen; Nicolas Bukowiecki

    2000-06-19

    The University of Minnesota Center for Diesel Research along with a research team including Caterpillar, Cummins, Carnegie Mellon University, West Virginia University (WVU), Paul Scherrer Institute in Switzerland, and Tampere University in Finland have performed measurements of Diesel exhaust particle size distributions under real-world dilution conditions. A mobile aerosol emission laboratory (MEL) equipped to measure particle size distributions, number concentrations, surface area concentrations, particle bound PAHs, as well as CO 2 and NO x concentrations in real time was built and will be described. The MEL was used to follow two different Cummins powered tractors, one with an older engine (L10) and one with a state-of-the-art engine (ISM), on rural highways and measure particles in their exhaust plumes. This paper will describe the goals and objectives of the study and will describe representative particle size distributions observed in roadway experiments with the truck powered by the ISM engine.

  9. In-Depth Temperature Profiles in Pyrolyzing Wood 

    E-Print Network [OSTI]

    Reszka, Pedro

    The move towards performance-based design of the fire resistance of structures requires more accurate design methods. An important variable in the fire performance of timber structures is the in-depth temperature distribution, as wood is weakened...

  10. Method and apparatus to measure the depth of skin burns

    DOE Patents [OSTI]

    Dickey, Fred M. (Albuquerque, NM); Holswade, Scott C. (Albuquerque, NM)

    2002-01-01

    A new device for measuring the depth of surface tissue burns based on the rate at which the skin temperature responds to a sudden differential temperature stimulus. This technique can be performed without physical contact with the burned tissue. In one implementation, time-dependent surface temperature data is taken from subsequent frames of a video signal from an infrared-sensitive video camera. When a thermal transient is created, e.g., by turning off a heat lamp directed at the skin surface, the following time-dependent surface temperature data can be used to determine the skin burn depth. Imaging and non-imaging versions of this device can be implemented, thereby enabling laboratory-quality skin burn depth imagers for hospitals as well as hand-held skin burn depth sensors the size of a small pocket flashlight for field use and triage.

  11. Optical penetration sensor for pulsed laser welding

    DOE Patents [OSTI]

    Essien, Marcelino (Albuquerque, NM); Keicher, David M. (Albuquerque, NM); Schlienger, M. Eric (Albuquerque, NM); Jellison, James L. (Albuquerque, NM)

    2000-01-01

    An apparatus and method for determining the penetration of the weld pool created from pulsed laser welding and more particularly to an apparatus and method of utilizing an optical technique to monitor the weld vaporization plume velocity to determine the depth of penetration. A light source directs a beam through a vaporization plume above a weld pool, wherein the plume changes the intensity of the beam, allowing determination of the velocity of the plume. From the velocity of the plume, the depth of the weld is determined.

  12. Observational Insights into Aerosol Formation from Isoprene David R. Worton,*,,

    E-Print Network [OSTI]

    Goldstein, Allen

    , Ronald C. Cohen, John H. Seinfeld, and Allen H. Goldstein,$ Department of Environmental Science, Policy and Management, Department of Chemistry, University of California, Berkeley, California 94720, United States Aerosol Dynamics Inc., Berkeley, California 94710, United States § Department of Environmental Sciences

  13. A review of Secondary Organic Aerosol (SOA) formation from isoprene

    E-Print Network [OSTI]

    Kroll, Jesse

    Recent field and laboratory evidence indicates that the oxidation of isoprene, (2-methyl-1,3-butadiene, C[subscript 5]H[subscript 8]) forms secondary organic aerosol (SOA). Global biogenic emissions of isoprene (600 Tg ...

  14. Toward a Minimal Representation of Aerosols in Climate Models...

    Office of Scientific and Technical Information (OSTI)

    carbon (BC) with other aerosol components, merging of the MAM7 fine dust and fine sea salt modes into the accumulation mode, merging of the MAM7 coarse dust and coarse sea salt...

  15. ris-r-1075(en) Quantitative Measurement of Aerosol

    E-Print Network [OSTI]

    and implications of deposition of potentially hazardous aerosol directly onto hu- mans. This state, beta doses from skin deposition to individuals in areas of Russia, where dry deposition of Chernobyl

  16. Experimental and numerical studies of aerosol penetration through screens 

    E-Print Network [OSTI]

    Han, Tae Won

    2009-05-15

    for one particular type of screen would collapse to a single curve if the collection efficiency is expressed in terms of non-dimensional parameters. Correlations characterizing the aerosol deposition process on different types of screens were developed...

  17. Aerosol-Cloud interactions : a new perspective in precipitation enhancement

    E-Print Network [OSTI]

    Gunturu, Udaya Bhaskar

    2010-01-01

    Increased industrialization and human activity modified the atmospheric aerosol composition and size-distribution during the last several decades. This has affected the structure and evolution of clouds, and precipitation ...

  18. On the relationship between stratospheric aerosols and nitrogen dioxide

    SciTech Connect (OSTI)

    Mills, M.J.; Langford, A.O.; O'Leary, T.J.; Arpag, K.; Miller, H.L.; Proffitt, M.H.; Sanders, R.W.; Solomon, S. (Aeronomy Laboratory, NOAA, Boulder, CO (United States) Univ. of Colorado, Boulder (United States))

    1993-06-18

    The authors report measurements of stratospheric column abundances of nitrogen dioxide above the Colorado mountains during Jan, Feb, and Mar 1992, following the arrival of the aerosol loading injected by Mt. Pinatubo. The column abundance data was correlated with concurrent lidar measurements which provided vertical aerosol profiles at the same site. Chemical reactions within polar stratospheric clouds have been shown to play a major role in ozone chemistry in the polar regions, and one could ask whether such clouds at mid latitudes could play a similar role. The sulfur dioxide loading due to the volcanic eruption provides an abrupt increase in sulfuric acid aerosol surface area in mid latitude areas, providing a convenient test of this question. Column NO[sub 2] densities are observed to fall, but also found to saturate at a certain stratospheric aerosol density.

  19. Persistent sensitivity of Asian aerosol to emissions of nitrogen oxides

    E-Print Network [OSTI]

    Kharol, S. K.

    We use a chemical transport model and its adjoint to examine the sensitivity of secondary inorganic aerosol formation to emissions of precursor trace gases from Asia. Sensitivity simulations indicate that secondary inorganic ...

  20. REPRESENTING AEROSOLS IN GLOBAL MODELS: FROM MICROMETERS TO MEGAMETERS

    E-Print Network [OSTI]

    Schwartz, Stephen E.

    mainly from gas-to- particle conversion of low-volatility gaseous species, mainly sulfuric acid to represent aerosol processes and forcing "on-line" in climate models in order to capture the feedbacks

  1. Case depth verification of hardened samples with Barkhausen noise sweeps

    SciTech Connect (OSTI)

    Santa-aho, Suvi; Vippola, Minnamari; Lepistö, Toivo [Tampere University of Technology, Department of Materials Science, P.O. Box 589, 33101 Tampere (Finland); Hakanen, Merja [Stresstech Oy, Tikkutehtaantie 1, 40800 Vaajakoski (Finland); Sorsa, Aki; Leiviskä, Kauko [University of Oulu, Control Engineering Laboratory, P.O. Box 4300, FIN-90014 University of Oulu (Finland)

    2014-02-18

    An interesting topic of recent Barkhausen noise (BN) method studies is the application of the method to case depth evaluation of hardened components. The utilization of BN method for this purpose is based on the difference in the magnetic properties between the hardened case and the soft core. Thus, the detection of case depth with BN can be achieved. The measurements typically have been carried out by using low magnetizing frequencies which have deeper penetration to the ferromagnetic samples than the conventional BN measurement. However, the penetration depth is limited due to eddy current damping of the signal. We introduce here a newly found sweep measurement concept for the case depth evaluation. In this study sweep measurements were carried out with various magnetizing frequencies and magnetizing voltages to detect the effect of different frequency and voltage and their correspondence to the actual case depth values verified from destructive characterization. Also a BN measurement device that has an implemented sweep analysis option was utilised. The samples were either induction or case-hardened samples and sample geometry contained both rod samples and gear axle samples with different case depth values. Samples were also further characterized with Xray diffraction to study the residual stress state of the surface. The detailed data processing revealed that also other calculated features than the maximum slope division of the 1st derivative of the BN signal could hold the information about the case depth value of the samples. The sweep method was able to arrange the axles into correct order according to the case depth value even though the axles were used.

  2. Organic Aerosol Component (OACOMP) Value-Added Product Report

    SciTech Connect (OSTI)

    Fast, J; Zhang, Q; Tilp, A; Shippert, T; Parworth, C; Mei, F

    2013-08-23

    Significantly improved returns in their aerosol chemistry data can be achieved via the development of a value-added product (VAP) of deriving OA components, called Organic Aerosol Components (OACOMP). OACOMP is primarily based on multivariate analysis of the measured organic mass spectral matrix. The key outputs of OACOMP are the concentration time series and the mass spectra of OA factors that are associated with distinct sources, formation and evolution processes, and physicochemical properties.

  3. Transport of anthropogenic and biomass burning aerosols from Europe to the Arctic during spring 2008

    SciTech Connect (OSTI)

    Marelle, L.; Raut, Jean-Christophe; Thomas, J. L.; Law, K. S.; Quennehen, Boris; Ancellet, G.; Pelon, J.; Schwarzenboeck, A.; Fast, Jerome D.

    2015-04-10

    During the POLARCAT-France airborne campaign in April 2008, pollution originating from anthropogenic and biomass burning emissions was measured in the European Arctic. We compare these aircraft measurements with simulations using the WRF-Chem model to investigate model representation of aerosols transported from Europe to the Arctic. Modeled PM2.5 is evaluated using European Monitoring and Evaluation Programme (EMEP) measurements in source regions and POLARCAT aircraft measurements in the Scandinavian Arctic. Total PM2.5 agrees well with the measurements, although the model overestimates nitrate and underestimates organic carbon in source regions. Using WRF-Chem in combination with the Lagrangian model FLEXPART-WRF, we find that during the campaign the research aircraft sampled two different types of European plumes: mixed anthropogenic and fire plumes from eastern Europe and Russia transported below 2 km, and anthropogenic plumes from central Europe uplifted by warm conveyor belt circulations to 5–6 km. Both modeled plume types had undergone significant wet scavenging (> 50% PM10) during transport. Modeled aerosol vertical distributions and optical properties below the aircraft are evaluated in the Arctic using airborne lidar measurements. Model results show that the pollution event transported aerosols into the Arctic (> 66.6° N) for a 4-day period. During this 4-day period, biomass burning emissions have the strongest influence on concentrations between 2.5 and 3 km altitudes, while European anthropogenic emissions influence aerosols at both lower (~ 1.5 km) and higher altitudes (~ 4.5 km). As a proportion of PM2.5, modeled black carbon and SO4= concentrations are more enhanced near the surface in anthropogenic plumes. The European plumes sampled during the POLARCAT-France campaign were transported over the region of springtime snow cover in northern Scandinavia, where they had a significant local atmospheric warming effect. We find that, during this transport event, the average modeled top-of-atmosphere (TOA) shortwave direct and semi-direct radiative effect (DSRE) north of 60° N over snow and ice-covered surfaces reaches +0.58 W m?2, peaking at +3.3 W m?2 at noon over Scandinavia and Finland.

  4. Transport of anthropogenic and biomass burning aerosols from Europe to the Arctic during spring 2008

    SciTech Connect (OSTI)

    Marelle, L.; Raut, Jean-Christophe; Thomas, J. L.; Law, K. S.; Quennehen, Boris; Ancellet, G.; Pelon, J.; Schwarzenboeck, A.; Fast, Jerome D.

    2015-01-01

    During the POLARCAT-France airborne campaign in April 2008, pollution originating from anthropogenic and biomass burning emissions was measured in the European Arctic. We compare these aircraft measurements with simulations using the WRF-Chem model to investigate model representation of aerosols transported from Europe to the Arctic. Modeled PM2.5 is evaluated using European Monitoring and Evaluation Programme (EMEP) measurements in source regions and POLARCAT aircraft measurements in the Scandinavian Arctic. Total PM2.5 agrees well with the measurements, although the model overestimates nitrate and underestimates organic carbon in source regions. Using WRF-Chem in combination with the Lagrangian model FLEXPART-WRF, we find that during the campaign the research aircraft sampled two different types of European plumes: mixed anthropogenic and fire plumes from eastern Europe and Russia transported below 2 km, and anthropogenic plumes from central Europe uplifted by warm conveyor belt circulations to 5–6 km. Both modeled plume types had undergone significant wet scavenging (> 50% PM10) during transport. Modeled aerosol vertical distributions and optical properties below the aircraft are evaluated in the Arctic using airborne lidar measurements. Model results show that the pollution event transported aerosols into the Arctic (> 66.6° N) for a 4-day period. During this 4-day period, biomass burning emissions have the strongest influence on concentrations between 2.5 and 3 km altitudes, while European anthropogenic emissions influence aerosols at both lower (~ 1.5 km) and higher altitudes (~ 4.5 km). As a proportion of PM2.5, modeled black carbon and SO4= concentrations are more enhanced near the surface in anthropogenic plumes. The European plumes sampled during the POLARCAT-France campaign were transported over the region of springtime snow cover in northern Scandinavia, where they had a significant local atmospheric warming effect. We find that, during this transport event, the average modeled top-of-atmosphere (TOA) shortwave direct and semi-direct radiative effect (DSRE) north of 60° N over snow and ice-covered surfaces reaches +0.58 W m?2, peaking at +3.3 W m?2 at noon over Scandinavia and Finland.

  5. Transport of anthropogenic and biomass burning aerosols from Europe to the Arctic during spring 2008

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Marelle, L.; Raut, Jean-Christophe; Thomas, J. L.; Law, K. S.; Quennehen, Boris; Ancellet, G.; Pelon, J.; Schwarzenboeck, A.; Fast, Jerome D.

    2015-04-10

    During the POLARCAT-France airborne campaign in April 2008, pollution originating from anthropogenic and biomass burning emissions was measured in the European Arctic. We compare these aircraft measurements with simulations using the WRF-Chem model to investigate model representation of aerosols transported from Europe to the Arctic. Modeled PM2.5 is evaluated using European Monitoring and Evaluation Programme (EMEP) measurements in source regions and POLARCAT aircraft measurements in the Scandinavian Arctic. Total PM2.5 agrees well with the measurements, although the model overestimates nitrate and underestimates organic carbon in source regions. Using WRF-Chem in combination with the Lagrangian model FLEXPART-WRF, we find that duringmore »the campaign the research aircraft sampled two different types of European plumes: mixed anthropogenic and fire plumes from eastern Europe and Russia transported below 2 km, and anthropogenic plumes from central Europe uplifted by warm conveyor belt circulations to 5–6 km. Both modeled plume types had undergone significant wet scavenging (> 50% PM10) during transport. Modeled aerosol vertical distributions and optical properties below the aircraft are evaluated in the Arctic using airborne lidar measurements. Model results show that the pollution event transported aerosols into the Arctic (> 66.6° N) for a 4-day period. During this 4-day period, biomass burning emissions have the strongest influence on concentrations between 2.5 and 3 km altitudes, while European anthropogenic emissions influence aerosols at both lower (~ 1.5 km) and higher altitudes (~ 4.5 km). As a proportion of PM2.5, modeled black carbon and SO4= concentrations are more enhanced near the surface in anthropogenic plumes. The European plumes sampled during the POLARCAT-France campaign were transported over the region of springtime snow cover in northern Scandinavia, where they had a significant local atmospheric warming effect. We find that, during this transport event, the average modeled top-of-atmosphere (TOA) shortwave direct and semi-direct radiative effect (DSRE) north of 60° N over snow and ice-covered surfaces reaches +0.58 W m?2, peaking at +3.3 W m?2 at noon over Scandinavia and Finland.« less

  6. Optical coupler

    DOE Patents [OSTI]

    Majewski, Stanislaw; Weisenberger, Andrew G.

    2004-06-15

    In a camera or similar radiation sensitive device comprising a pixilated scintillation layer, a light guide and an array of position sensitive photomultiplier tubes, wherein there exists so-called dead space between adjacent photomultiplier tubes the improvement comprising a two part light guide comprising a first planar light spreading layer or portion having a first surface that addresses the scintillation layer and optically coupled thereto at a second surface that addresses the photomultiplier tubes, a second layer or portion comprising an array of trapezoidal light collectors defining gaps that span said dead space and are individually optically coupled to individual position sensitive photomultiplier tubes. According to a preferred embodiment, coupling of the trapezoidal light collectors to the position sensitive photomultiplier tubes is accomplished using an optical grease having about the same refractive index as the material of construction of the two part light guide.

  7. Optical memory

    DOE Patents [OSTI]

    Mao, Samuel S; Zhang, Yanfeng

    2013-07-02

    Optical memory comprising: a semiconductor wire, a first electrode, a second electrode, a light source, a means for producing a first voltage at the first electrode, a means for producing a second voltage at the second electrode, and a means for determining the presence of an electrical voltage across the first electrode and the second electrode exceeding a predefined voltage. The first voltage, preferably less than 0 volts, different from said second voltage. The semiconductor wire is optically transparent and has a bandgap less than the energy produced by the light source. The light source is optically connected to the semiconductor wire. The first electrode and the second electrode are electrically insulated from each other and said semiconductor wire.

  8. Optical analyzer

    DOE Patents [OSTI]

    Hansen, A.D.

    1987-09-28

    An optical analyzer wherein a sample of particulate matter, and particularly of organic matter, which has been collected on a quartz fiber filter is placed in a combustion tube, and light from a light source is passed through the sample. The temperature of the sample is raised at a controlled rate and in a controlled atmosphere. The magnitude of the transmission of light through the sample is detected as the temperature is raised. A data processor, differentiator and a two pen recorder provide a chart of the optical transmission versus temperature and the rate of change of optical transmission versus temperature signatures (T and D) of the sample. These signatures provide information as to physical and chemical processes and a variety of quantitative and qualitative information about the sample. Additional information is obtained by repeating the run in different atmospheres and/or different rates or heating with other samples of the same particulate material collected on other filters. 7 figs.

  9. On modification of global warming by sulfate aerosols

    SciTech Connect (OSTI)

    Mitchell, J.F.B.; Johns, T.C.

    1997-02-01

    There is increasing evidence that the response of climate to increasing greenhouse gases may be modified by accompanying increases in sulfate aerosols. In this study, the patterns of response in the surface climatology of a coupled ocean-atmosphere general circulation model forced by increases in carbon dioxide alone is compared with those obtained by increasing carbon dioxide and aerosol forcing. The simulations are run from early industrial times using the estimated historical forcing and continued to the end of the twenty-first century assuming a nonintervention emissions scenario for greenhouse gases and aerosols. The comparison is made for the period 2030-2050 when the aerosol forcing is a maximum. In winter, the cooling due to aerosols merely tends to reduce the response to carbon dioxide, whereas in summer, it weakens the monsoon circulations and reverses some of the changes in the hydrological cycle on increasing carbon dioxide. This response is in some respects similar to that found in simulations with changed orbital parameters, as between today and the middle Holocene. The hydrological response in the palaeosimulations is supported by palaeoclimatic reconstructions. The results of changes in aerosol concentrations of the magnetic projected in the scenarios would have a major effect on regional climate, especially over Europe and Southeast Asia. 74 refs., 12 figs., 6 tabs.

  10. Effect of Terrestrial and Marine Organic Aerosol on Regional and Global Climate: Model Development, Application, and Verification with Satellite Data

    SciTech Connect (OSTI)

    Meskhidze, Nicholas; Zhang, Yang; Kamykowski, Daniel

    2012-03-28

    In this DOE project the improvements to parameterization of marine primary organic matter (POM) emissions, hygroscopic properties of marine POM, marine isoprene derived secondary organic aerosol (SOA) emissions, surfactant effects, new cloud droplet activation parameterization have been implemented into Community Atmosphere Model (CAM 5.0), with a seven mode aerosol module from the Pacific Northwest National Laboratory (PNNL)���¢��������s Modal Aerosol Model (MAM7). The effects of marine aerosols derived from sea spray and ocean emitted biogenic volatile organic compounds (BVOCs) on microphysical properties of clouds were explored by conducting 10 year CAM5.0-MAM7 model simulations at a grid resolution 1.9�������°��������2.5�������° with 30 vertical layers. Model-predicted relationship between ocean physical and biological systems and the abundance of CCN in remote marine atmosphere was compared to data from the A-Train satellites (MODIS, CALIPSO, AMSR-E). Model simulations show that on average, primary and secondary organic aerosol emissions from the ocean can yield up to 20% increase in Cloud Condensation Nuclei (CCN) at 0.2% Supersaturation, and up to 5% increases in droplet number concentration of global maritime shallow clouds. Marine organics were treated as internally or externally mixed with sea salt. Changes associated with cloud properties reduced (absolute value) the model-predicted short wave cloud forcing from -1.35 Wm-2 to -0.25 Wm-2. By using different emission scenarios, and droplet activation parameterizations, this study suggests that addition of marine primary aerosols and biologically generated reactive gases makes an important difference in radiative forcing assessments. All baseline and sensitivity simulations for 2001 and 2050 using global-through-urban WRF/Chem (GU-WRF) were completed. The main objective of these simulations was to evaluate the capability of GU-WRF for an accurate representation of the global atmosphere by exploring the most accurate configuration of physics options in GWRF for global scale modeling in 2001 at a horizontal grid resolution of 1�������° x 1�������°. GU-WRF model output was evaluated using observational datasets from a variety of sources including surface based observations (NCDC and BSRN), model reanalysis (NCEP/ NCAR Reanalysis and CMAP), and remotely-sensed data (TRMM) to evaluate the ability of GU-WRF to simulate atmospheric variables at the surface as well as aloft. Explicit treatment of nanoparticles produced from new particle formation in GU-WRF/Chem-MADRID was achieved by expanding particle size sections from 8 to 12 to cover particles with the size range of 1.16 nm to 11.6 �������µm. Simulations with two different nucleation parameterizations were conducted for August 2002 over a global domain at a 4�������º by 5�������º horizontal resolution. The results are evaluated against field measurement data from the 2002 Aerosol Nucleation and Real Time Characterization Experiment (ANARChE) in Atlanta, Georgia, as well as satellite and reanalysis data. We have also explored the relationship between ���¢��������clean marine���¢������� aerosol optical properties and ocean surface wind speed using remotely sensed data from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) on board the CALIPSO satellite and the Advanced Microwave Scanning Radiometer (AMSR-E) on board the AQUA satellite. Detailed data analyses

  11. Investigations of cloud altering effects of atmospheric aerosols using a new mixed Eulerian-Lagrangian aerosol model

    E-Print Network [OSTI]

    Steele, Henry Donnan, 1974-

    2004-01-01

    Industry, urban development, and other anthropogenic influences have substantially altered the composition and size-distribution of atmospheric aerosol particles over the last century. This, in turn, has altered cloud ...

  12. Climatic effects of 1950–2050 changes in US anthropogenic aerosols – Part 1: Aerosol trends and radiative forcing

    E-Print Network [OSTI]

    Leibensperger, Eric Michael

    We use the GEOS-Chem chemical transport model combined with the GISS general circulation model to calculate the aerosol direct and indirect (warm cloud) radiative forcings from US anthropogenic sources over the 1950–2050 ...

  13. COLLABORATIVE RESEARCH: Study of Aerosol Sources and Processing at the GVAX Pantnagar Supersite

    SciTech Connect (OSTI)

    Worsnop, Douglas R.

    2014-07-28

    This project funded the participation of scientists from seven research groups, running more than thirty instruments, in the Winter Intensive Operating Period (January-February 2012) of the Clean Air for London (ClearfLo) campaign at a rural site in Detling, UK, 45 km southeast of central London. The primary science questions for the ClearfLo Winter IOP were, 1) what is the urban increment of particulate matter (PM) and other pollutants in the greater London area, and, 2) what is the contribution of solid fuel use for home heating to wintertime PM? An additional motivation for the Detling measurements was the question of whether coatings on black carbon particles enhance absorption. The following four key accomplishments have been identified so far: 1) Chemical, physical and optical characterization of PM from local and regional sources (Figures 2, 4, 5 and 6). 2) Measurement of urban increment in particulate matter and gases in London (Figure 3). 3) Measurement of optical properties and chemical composition of coatings on black carbon containing particles indicates absorption enhancement. 4) First deployment of chemical ionization instrument (MOVI-CI-TOFMS) to measure both particle-phase and gas-phase organic acids. (See final report from Joel Thornton, University of Washington, for details.) Analysis of the large dataset acquired in Detling is ongoing and will yield further key accomplishments. These measurements of urban and rural aerosol properties will contribute to improved modeling of regional aerosol emissions, and of atmospheric aging and removal. The measurement of absorption enhancement by coatings on black carbon will contribute to improved modeling of the direct radiative properties of PM.

  14. An Aerosol Condensation Model for Sulfur Trioxide

    SciTech Connect (OSTI)

    Grant, K E

    2008-02-07

    This document describes a model for condensation of sulfuric acid aerosol given an initial concentration and/or source of gaseous sulfur trioxide (e.g. fuming from oleum). The model includes the thermochemical effects on aerosol condensation and air parcel buoyancy. Condensation is assumed to occur heterogeneously onto a preexisting background aerosol distribution. The model development is both a revisiting of research initially presented at the Fall 2001 American Geophysical Union Meeting [1] and a further extension to provide new capabilities for current atmospheric dispersion modeling efforts [2]. Sulfuric acid is one of the most widely used of all industrial chemicals. In 1992, world consumption of sulfuric acid was 145 million metric tons, with 42.4 Mt (mega-tons) consumed in the United States [10]. In 2001, of 37.5 Mt consumed in the U.S., 74% went into producing phosphate fertilizers [11]. Another significant use is in mining industries. Lawuyi and Fingas [7] estimate that, in 1996, 68% of use was for fertilizers and 5.8% was for mining. They note that H{sub 2}SO{sub 4} use has been and should continue to be very stable. In the United States, the elimination of MTBE (methyl tertiary-butyl ether) and the use of ethanol for gasoline production are further increasing the demand for petroleum alkylate. Alkylate producers have a choice of either a hydrofluoric acid or sulfuric acid process. Both processes are widely used today. Concerns, however, over the safety or potential regulation of hydrofluoric acid are likely to result in most of the growth being for the sulfuric acid process, further increasing demand [11]. The implication of sulfuric acid being a pervasive industrial chemical is that transport is also pervasive. Often, this is in the form of oleum tankers, having around 30% free sulfur trioxide. Although sulfuric acid itself is not a volatile substance, fuming sulfuric acid (referred to as oleum) is [7], the volatile product being sulfur trioxide. Sulfate aerosols and mist may form in the atmosphere on tank rupture. From chemical spill data from 1990-1996, Lawuyi02 and Fingas [7] prioritize sulfuric acid as sixth most serious. During this period, they note 155 spills totaling 13 Mt, out of a supply volume of 3700 Mt. Lawuyi and Fingas [7] summarize information on three major sulfuric acid spills. On 12 February 1984, 93 tons of sulfuric acid were spilled when 14 railroad cars derailed near MacTier, Parry Sound, Ontario. On 13 December 1978, 51 railroad cars derailed near Springhill, Nova Scotia. One car, containing 93% sulfuric acid, ruptured, spilling nearly its entire contents. In July 1993, 20 to 50 tons of fuming sulfuric acid spilled at the General Chemical Corp. plant in Richmond, California, a major industrial center near San Francisco. The release occurred when oleum was being loaded into a nonfuming acid railroad tank car that contained only a rupture disk as a safety device. The tank car was overheated and this rupture disk blew. The resulting cloud of sulfuric acid drifted northeast with prevailing winds over a number of populated areas. More than 3,000 people subsequently sought medical attention for burning eyes, coughing, headaches, and nausea. Almost all were treated and released on the day of the spill. By the day after the release, another 5,000 people had sought medical attention. The spill forced the closure of five freeways in the region as well as some Bay Area Rapid Transit System stations. Apart from corrosive toxicity, there is the additional hazard that the reactions of sulfur trioxide and sulfuric acid vapors with water are extremely exothermic [10, 11]. While the vapors are intrinsically denser than air, there is thus the likelihood of strong, warming-induced buoyancy from reactions with ambient water vapor, water-containing aerosol droplets, and wet environmental surface. Nordin [12] relates just such an occurrence following the Richmond, CA spill, with the plume observed to rise to 300 m. For all practical purposes, sulfur trioxide was the constituent released from the heated tank

  15. Aerosol specification in single-column CAM5

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Lebassi-Habtezion, B.; Caldwell, P.

    2014-11-17

    The ability to run a global climate model in single-column mode is very useful for testing model improvements because single-column models (SCMs) are inexpensive to run and easy to interpret. A major breakthrough in Version 5 of the Community Atmosphere Model (CAM5) is the inclusion of prognostic aerosol. Unfortunately, this improvement was not coordinated with the SCM version of CAM5 and as a result CAM5-SCM initializes aerosols to zero. In this study we explore the impact of running CAM5-SCM with aerosol initialized to zero (hereafter named Default) and test three potential fixes. The first fix is to use CAM5'smore »prescribed aerosol capability, which specifies aerosols at monthly climatological values. The second method is to prescribe aerosols at observed values. The third approach is to fix droplet and ice crystal numbers at prescribed values. We test our fixes in four different cloud regimes to ensure representativeness: subtropical drizzling stratocumulus (based on the DYCOMS RF02 case study), mixed-phase Arctic stratocumulus (using the MPACE-B case study), tropical shallow convection (using the RICO case study), and summertime mid-latitude continental convection (using the ARM95 case study). Stratiform cloud cases (DYCOMS RF02 and MPACE-B) were found to have a strong dependence on aerosol concentration, while convective cases (RICO and ARM95) were relatively insensitive to aerosol specification. This is perhaps expected because convective schemes in CAM5 do not currently use aerosol information. Adequate liquid water content in the MPACE-B case was only maintained when ice crystal number concentration was specified because the Meyers et al. (1992) deposition/condensation ice nucleation scheme used by CAM5 greatly overpredicts ice nucleation rates, causing clouds to rapidly glaciate. Surprisingly, predicted droplet concentrations for the ARM95 region in both SCM and global runs were around 25 cm?3, which is much lower than observed. This finding suggests that CAM5 has problems capturing aerosol effects in this climate regime.« less

  16. Spent fuel sabotage aerosol test program :FY 2005-06 testing and aerosol data summary.

    SciTech Connect (OSTI)

    Gregson, Michael Warren; Brockmann, John E.; Nolte, O. (Fraunhofer institut fur toxikologie und experimentelle Medizin, Germany); Loiseau, O. (Institut de radioprotection et de Surete Nucleaire, France); Koch, W. (Fraunhofer institut fur toxikologie und experimentelle Medizin, Germany); Molecke, Martin Alan; Autrusson, Bruno (Institut de radioprotection et de Surete Nucleaire, France); Pretzsch, Gunter Guido (Gesellschaft fur anlagen- und Reaktorsicherheit, Germany); Billone, M. C. (Argonne National Laboratory, USA); Lucero, Daniel A.; Burtseva, T. (Argonne National Laboratory, USA); Brucher, W (Gesellschaft fur anlagen- und Reaktorsicherheit, Germany); Steyskal, Michele D.

    2006-10-01

    This multinational, multi-phase spent fuel sabotage test program is quantifying the aerosol particles produced when the products of a high energy density device (HEDD) interact with and explosively particulate test rodlets that contain pellets of either surrogate materials or actual spent fuel. This program has been underway for several years. This program provides source-term data that are relevant to some sabotage scenarios in relation to spent fuel transport and storage casks, and associated risk assessments. This document focuses on an updated description of the test program and test components for all work and plans made, or revised, primarily during FY 2005 and about the first two-thirds of FY 2006. It also serves as a program status report as of the end of May 2006. We provide details on the significant findings on aerosol results and observations from the recently completed Phase 2 surrogate material tests using cerium oxide ceramic pellets in test rodlets plus non-radioactive fission product dopants. Results include: respirable fractions produced; amounts, nuclide content, and produced particle size distributions and morphology; status on determination of the spent fuel ratio, SFR (the ratio of respirable particles from real spent fuel/respirables from surrogate spent fuel, measured under closely matched test conditions, in a contained test chamber); and, measurements of enhanced volatile fission product species sorption onto respirable particles. We discuss progress and results for the first three, recently performed Phase 3 tests using depleted uranium oxide, DUO{sub 2}, test rodlets. We will also review the status of preparations and the final Phase 4 tests in this program, using short rodlets containing actual spent fuel from U.S. PWR reactors, with both high- and lower-burnup fuel. These data plus testing results and design are tailored to support and guide, follow-on computer modeling of aerosol dispersal hazards and radiological consequence assessments. This spent fuel sabotage--aerosol test program, performed primarily at Sandia National Laboratories, with support provided by both the U.S. Department of Energy and the Nuclear Regulatory Commission, had significant inputs from, and is strongly supported and coordinated by both the U.S. and international program participants in Germany, France, and the U.K., as part of the international Working Group for Sabotage Concerns of Transport and Storage Casks, WGSTSC.

  17. Measuring depth profiles of residual stress with Raman spectroscopy

    SciTech Connect (OSTI)

    Enloe, W.S.; Sparks, R.G.; Paesler, M.A.

    1988-12-01

    Knowledge of the variation of residual stress is a very important factor in understanding the properties of machined surfaces. The nature of the residual stress can determine a part`s susceptibility to wear deformation, and cracking. Raman spectroscopy is known to be a very useful technique for measuring residual stress in many materials. These measurements are routinely made with a lateral resolution of 1{mu}m and an accuracy of 0.1 kbar. The variation of stress with depth; however, has not received much attention in the past. A novel technique has been developed that allows quantitative measurement of the variation of the residual stress with depth with an accuracy of 10nm in the z direction. Qualitative techniques for determining whether the stress is varying with depth are presented. It is also demonstrated that when the stress is changing over the volume sampled, errors can be introduced if the variation of the stress with depth is ignored. Computer aided data analysis is used to determine the depth dependence of the residual stress.

  18. Large Enhancement in the Heterogeneous Oxidation Rate of Organic Aerosols by Hydroxyl Radicals in the Presence of Nitric Oxide.

    E-Print Network [OSTI]

    Richards-Henderson, NK; Goldstein, AH; Wilson, KR

    2015-01-01

    Heterogeneous Reaction of Hydroxyl Radicals with Sub-Micronof Organic Aerosols by Hydroxyl Radicals in the Presence ofin an aerosol exposed to hydroxyl radicals (OH) is thought

  19. Effects on precipitation, clouds, and temperature from long-range transport of idealized aerosol plumes in WRF-Chem simulations

    E-Print Network [OSTI]

    Zhao, Zhan; Pritchard, Michael S; Russell, Lynn M

    2012-01-01

    on intense convective precipitation in the northeastern US,aerosols on regional precipitation over East Asia, J.of aerosols on surface precipitation from clouds: An attempt

  20. Sandia Energy - Quantum Optics

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Quantum Optics Home Energy Research EFRCs Solid-State Lighting Science EFRC Quantum Optics Quantum OpticsTara Camacho-Lopez2015-03-30T16:37:03+00:00 Quantum Optics with a Single...

  1. Depth-resolved confocal micro-Raman spectroscopy for characterizing GaN-based light emitting diode structures

    SciTech Connect (OSTI)

    Chen, Wei-Liang; Lee, Yu-Yang; Chang, Yu-Ming, E-mail: ymchang@ntu.edu.tw [Center for Condensed Matter Sciences, National Taiwan University, 10617 Taipei, Taiwan (China)] [Center for Condensed Matter Sciences, National Taiwan University, 10617 Taipei, Taiwan (China); Chang, Chiao-Yun; Huang, Huei-Min; Lu, Tien-Chang [Department of Photonics, National Chiao Tung University, 30010 Hsinchu, Taiwan (China)] [Department of Photonics, National Chiao Tung University, 30010 Hsinchu, Taiwan (China)

    2013-11-15

    In this work, we demonstrate that depth-resolved confocal micro-Raman spectroscopy can be used to characterize the active layer of GaN-based LEDs. By taking the depth compression effect due to refraction index mismatch into account, the axial profiles of Raman peak intensities from the GaN capping layer toward the sapphire substrate can correctly match the LED structural dimension and allow the identification of unique Raman feature originated from the 0.3 ?m thick active layer of the studied LED. The strain variation in different sample depths can also be quantified by measuring the Raman shift of GaN A{sub 1}(LO) and E{sub 2}(high) phonon peaks. The capability of identifying the phonon structure of buried LED active layer and depth-resolving the strain distribution of LED structure makes this technique a potential optical and remote tool for in operando investigation of the electronic and structural properties of nitride-based LEDs.

  2. Practical application of in situ aerosol measurement

    SciTech Connect (OSTI)

    O`Hern, T.J.; Rader, D.J.

    1993-09-01

    The use of in situ, real-time measurement techniques permits the characterization of airborne droplets and particles under conditions where traditional sampling methods can fail. For example, sampling method rely on the ability to sample and transport particles without biasing the properties of interest, and often are not applicable in harsh environment. Although in situ methods offer unique opportunities in these cases, these techniques introduce new concerns and must be used carefully if accurate measurement are to be made. Several in situ measurement techniques are reviewed here. As the field is rapidly evolving, the discussion is limited to those techniques which: (1) are commercially available, (2) provide real-time output, (3) measure the aerosol size distribution. Discussion is divided between single particle counters (which provide a flux-based or temporal measurement) and ensemble techniques (which provide a concentration-based or spatial measurement). Specific techniques discussed include phase Doppler, Mie scattering, and Fraunhofer diffraction, and commercial instruments based on these techniques.

  3. Mechanisms of aerosol-forced AMOC variability in a state of the art climate model

    E-Print Network [OSTI]

    with a new state-of-the-art Earth system model. Anthropogenic aerosols have previously been highlighted anthropogenic aerosols force a strengthening of the AMOC by up to 20% in our state-of-the-art Earth system model

  4. Investigation of the aerosol-cloud interaction using the WRF framework 

    E-Print Network [OSTI]

    Li, Guohui

    2009-05-15

    In this dissertation, a two-moment bulk microphysical scheme with aerosol effects is developed and implemented into the Weather Research and Forecasting (WRF) model to investigate the aerosol-cloud interaction. Sensitivities ...

  5. CHASER: An Innovative Satellite Mission Concept to Measure the Effects of Aerosols on Clouds and Climate

    E-Print Network [OSTI]

    Rosenfeld, Daniel

    The formation of cloud droplets on aerosol particles, technically known as the activation of cloud condensation nuclei (CCN), is the fundamental process driving the interactions of aerosols with clouds and precipitation. ...

  6. Secondary organic aerosol formation from fossil fuel sources contribute majority of summertime organic mass at Bakersfield

    E-Print Network [OSTI]

    Cohen, Ronald C.

    Secondary organic aerosol formation from fossil fuel sources contribute majority of summertime organic aerosol formation from fossil fuel sources contribute majority of summertime organic mass is fossil fuel combustion from gasoline- and diesel- powered vehicles and other industrial activities (e

  7. Computational fluid dynamics (CFD) simulations of aerosol in a u-shaped steam generator tube 

    E-Print Network [OSTI]

    Longmire, Pamela

    2009-05-15

    To quantify primary side aerosol retention, an Eulerian/Lagrangian approach was used to investigate aerosol transport in a compressible, turbulent, adiabatic, internal, wall-bounded flow. The ARTIST experimental project ...

  8. Variablity among electronic cigarettes in the pressure drop, airflow rate, and aerosol production

    E-Print Network [OSTI]

    Talbot, Prue

    2013-01-01

    on the Ruyan e-cigarette cartridge and inhaled aerosol (pp.drop, length of time cartridges lasted, and production ofdevice that aerosolizes cartridge fluid which is in turn

  9. Variability of aerosol parameters over Kanpur, northern India R. P. Singh,1

    E-Print Network [OSTI]

    Singh, Ramesh P.

    Variability of aerosol parameters over Kanpur, northern India R. P. Singh,1 Sagnik Dey, S. N Dynamics: Remote sensing; KEYWORDS: aerosol, remote sensing, Ganga basin Citation: Singh, R. P., S. Dey, S

  10. The impact of pathological ventilation on aerosol deposition : imaging, insight and intervention

    E-Print Network [OSTI]

    Greenblatt, Elliot (Elliot Eliyahu)

    2015-01-01

    Aerosol therapies are often used to treat lung diseases in which ventilation is distributed heterogeneously throughout the lung. As therapeutic aerosols are transported by the inhaled air, it is likely that deposition is ...

  11. Climate effects of seasonally varying Biomass Burning emitted Carbonaceous Aerosols (BBCA)

    E-Print Network [OSTI]

    Jeong, Gill-Ran

    The climate impact of the seasonality of Biomass Burning emitted Carbonaceous Aerosols (BBCA) is studied using an aerosol-climate model coupled with a slab ocean model in a set of 60-year long simulations, driven by BBCA ...

  12. Parallel optical sampler

    DOE Patents [OSTI]

    Tauke-Pedretti, Anna; Skogen, Erik J; Vawter, Gregory A

    2014-05-20

    An optical sampler includes a first and second 1.times.n optical beam splitters splitting an input optical sampling signal and an optical analog input signal into n parallel channels, respectively, a plurality of optical delay elements providing n parallel delayed input optical sampling signals, n photodiodes converting the n parallel optical analog input signals into n respective electrical output signals, and n optical modulators modulating the input optical sampling signal or the optical analog input signal by the respective electrical output signals, and providing n successive optical samples of the optical analog input signal. A plurality of output photodiodes and eADCs convert the n successive optical samples to n successive digital samples. The optical modulator may be a photodiode interconnected Mach-Zehnder Modulator. A method of sampling the optical analog input signal is disclosed.

  13. Atmos. Chem. Phys., 9, 48114826, 2009 www.atmos-chem-phys.net/9/4811/2009/

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    aerosols influence the radiative budget of the earth directly by scattering and absorbing solar radiation and optical depth to date. The observed bias differences in ambient aerosol extinction between HSRL and other aerosol radiative effects on climate change, the Intergovernmental Panel on Climate Change concluded

  14. Characterization of Pre-Commercial Gasoline Engine Particulates Through Advanced Aerosol Methods

    Broader source: Energy.gov [DOE]

    Advanced aerosol analysis methods were used to examine particulates from single cylinder test engines running on gasoline and ethanol blends.

  15. Observed high-altitude warming and snow cover retreat over Tibet and the Himalayas enhanced by black carbon aerosols

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Xu, Y.; Ramanathan, V.; Washington, W. M.

    2015-07-10

    Himalayan mountain glaciers and the snowpack over the Tibetan Plateau provide the headwater of several major rivers in Asia. In-situ observations of snow cover fraction since the 1960s suggest that the snow pack in the region have retreated significantly, accompanied by a surface warming of 2–2.5 °C observed over the peak altitudes (5000 m). Using a high-resolution ocean–atmosphere global climate model and an observationally constrained black carbon (BC) aerosol forcing, we attribute the observed altitude dependence of the warming trends as well as the spatial pattern of reductions in snow depths and snow cover fraction to various anthropogenic factors. Atmore »the Tibetan Plateau altitudes, the increase of atmospheric CO2 concentration exerted a warming of 1.7 °C, BC 1.3 °C where as cooling aerosols cause about 0.7 °C cooling, bringing the net simulated warming consistent with the anomalously large observed warming. We therefore conclude that BC together with CO2 has contributed to the snow retreat trends. Especially, BC increase is the major factor in the strong elevation dependence of the observed surface warming. The atmospheric warming by BC as well as its surface darkening of snow are coupled with the positive snow albedo feedbacks to account for the disproportionately large role of BC in high-elevation regions. These findings reveal that BC impact needs to be properly accounted for in future regional climate projections, in particular on high-altitude cryosphere.« less

  16. Final Technical Report for "Ice nuclei relation to aerosol properties: Data analysis and model parameterization for IN in mixed-phase clouds"� (DOE/SC00002354)

    SciTech Connect (OSTI)

    Paul J. DeMott, Anthony J. Prenni; Sonia M. Kreidenweis

    2012-09-28

    Clouds play an important role in weather and climate. In addition to their key role in the hydrologic cycle, clouds scatter incoming solar radiation and trap infrared radiation from the surface and lower atmosphere. Despite their importance, feedbacks involving clouds remain as one of the largest sources of uncertainty in climate models. To better simulate cloud processes requires better characterization of cloud microphysical processes, which can affect the spatial extent, optical depth and lifetime of clouds. To this end, we developed a new parameterization to be used in numerical models that describes the variation of ice nuclei (IN) number concentrations active to form ice crystals in mixed-phase (water droplets and ice crystals co-existing) cloud conditions as these depend on existing aerosol properties and temperature. The parameterization is based on data collected using the Colorado State University continuous flow diffusion chamber in aircraft and ground-based campaigns over a 14-year period, including data from the DOE-supported Mixed-Phase Arctic Cloud Experiment. The resulting relationship is shown to more accurately represent the variability of ice nuclei distributions in the atmosphere compared to currently used parameterizations based on temperature alone. When implemented in one global climate model, the new parameterization predicted more realistic annually averaged cloud water and ice distributions, and cloud radiative properties, especially for sensitive higher latitude mixed-phase cloud regions. As a test of the new global IN scheme, it was compared to independent data collected during the 2008 DOE-sponsored Indirect and Semi-Direct Aerosol Campaign (ISDAC). Good agreement with this new data set suggests the broad applicability of the new scheme for describing general (non-chemically specific) aerosol influences on IN number concentrations feeding mixed-phase Arctic stratus clouds. Finally, the parameterization was implemented into a regional cloud-resolving model to compare predictions of ice crystal concentrations and other cloud properties to those observed in two intensive case studies of Arctic stratus during ISDAC. Our implementation included development of a prognostic scheme of ice activation using the IN parameterization so that the most realistic treatment of ice nuclei, including their budget (gains and losses), was achieved. Many cloud microphysical properties and cloud persistence were faithfully reproduced, despite a tendency to under-predict (by a few to several times) ice crystal number concentrations and cloud ice mass, in agreement with some other studies. This work serves generally as the basis for improving predictive schemes for cloud ice crystal activation in cloud and climate models, and more specifically as the basis for such a scheme to be used in a Multi-scale Modeling Format (MMF) that utilizes a connected system of cloud-resolving models on a global grid in an effort to better resolve cloud processes and their influence on climate.

  17. Noise Analysis and Synthesis for 3D Laser Depth Scanners

    E-Print Network [OSTI]

    Martin, Ralph R.

    Noise Analysis and Synthesis for 3D Laser Depth Scanners Xianfang Sun a,b,, Paul L. Rosin a , Ralph the noise present in range data measured by a Konica Minolta Vivid 910 scanner, in order to better characterise real scanner noise. Methods for denoising 3D mesh data have often assumed the noise to be Gaussian

  18. Continuous Snow Depth, Intensive Site 1, Barrow, Alaska

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Bob Busey; Larry Hinzman; Vladimir Romanovsky; William Cable

    Continuous Snow depth data are being collected at several points within four intensive study areas in Barrow, Alaska. These data are being collected to better understand the energy dynamics above the active layer and permafrost. They complement in-situ snow and soil measurements at this location. The data could also be used as supporting measurements for other research and modeling activities.

  19. Electrical Resistivity Imaging for Unknown Bridge Foundation Depth Determination 

    E-Print Network [OSTI]

    Arjwech, Rungroj

    2012-02-14

    as suitable to investigate unknown bridge foundations. The objective of the present study is to apply advanced 2D electrical resistivity imaging (ERI) in order to identify depth of unknown bridge foundations. A survey procedure is carried out in mixed terrain...

  20. Depth Energy Image for Gait Symmetry Quantification Caroline Rougier1

    E-Print Network [OSTI]

    Mignotte, Max

    Depth Energy Image for Gait Symmetry Quantification Caroline Rougier1 , Edouard Auvinet1 , Jean´erationnelle, Universit´e de Montr´eal, Canada {rougierc, auvinet, meunier, mignotte}@iro.umontreal.ca 2 Centre de recherche du Centre Hospitalier de l'Universit´e de Montr´eal, ETS, Canada jacques

  1. Wave-current interaction in water of finite depth

    E-Print Network [OSTI]

    Huang, Zhenhua, 1967-

    2004-01-01

    In this thesis, the nonlinear interaction of waves and current in water of finite depth is studied. Wind is not included. In the first part, a 2D theory for the wave effect on a turbulent current over rough or smooth bottom ...

  2. Continuous Snow Depth, Intensive Site 1, Barrow, Alaska

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Bob Busey; Larry Hinzman; Vladimir Romanovsky; William Cable

    2014-11-06

    Continuous Snow depth data are being collected at several points within four intensive study areas in Barrow, Alaska. These data are being collected to better understand the energy dynamics above the active layer and permafrost. They complement in-situ snow and soil measurements at this location. The data could also be used as supporting measurements for other research and modeling activities.

  3. Lower Bounds on Interactive Compressibility by Constant-Depth Circuits

    E-Print Network [OSTI]

    Edinburgh, University of

    Lower Bounds on Interactive Compressibility by Constant-Depth Circuits Arkadev Chattopadhyay to prove the first lower bounds on general probabilistic multi-round instance compression. We show, and strengthens results of Dubrov and Ishai [DI06]. We also show that a similar lower bound holds for Majority. We

  4. 7 Predictive Risk Mapping of Water Table Depths in

    E-Print Network [OSTI]

    Camara, Gilberto

    73 7 Predictive Risk Mapping of Water Table Depths in a Brazilian Cerrado Area R. L. Manzione, M extend from the northern margins of the Amazon rain for- ests to outliers on the southern borders metabolize throughout the year, drawing on soil water reserves, and can withstand short-lived fires. contents

  5. Dual-depth adapted irreducible formal multizeta values Leila Schneps

    E-Print Network [OSTI]

    Schneps, Leila

    , and the relations between them. Consider the following diagram, in which the four top spaces are Hopf algebras the double shuffle Lie algebra, equipped with the standard weight grading and depth filtration; we write ds = n3dsn and denote the filtration by ds1 ds2 · · ·. The double shuffle Lie algebra is dual

  6. Optical Tweezers Physics 464 Applied Optics,

    E-Print Network [OSTI]

    Optical Tweezers Physics 464 ­ Applied Optics, By Scott Cline #12;Project Topics · Brief history · Typical set-up · How they work · Common use #12;Discovery · Effects of optical scattering and gradient forces discovered by Arthur Ashkin 1970 · Method of creating an "optical trap" established in 1986

  7. Optical Packet Switching -1 Optical Networks

    E-Print Network [OSTI]

    Mellia, Marco

    Optical Packet Switching - 1 Optical Networks: from fiber transmission to photonic switching Optical Packet Switching Fabio Neri and Marco Mellia TLC Networks Group ­ Electronics Department e.mellia@polito.it ­ tel. 011 564 4173 #12;Optical Packet Switching - 2 · This work is licensed under the Creative Commons

  8. Global observations of UV-absorbing aerosols from ERS-2/GOME Data

    E-Print Network [OSTI]

    Graaf, Martin de

    Absorbing Aerosol Index ­ Theory GOME AAI results Conclusions & Outlook #12; Absorbing Aerosol Index Solar zenith angle = 30° Viewing zenith angle = 0° Surface albedo = 5% #12; Reflectance at TOA with absorbing aerosols Doubling-Adding KNMI Radiative Transfer Model Solar zenith angle = 30° Viewing zenith

  9. Uncertainty and interpretation of aerosol remote sensing due to vertical inhomogeneity

    E-Print Network [OSTI]

    , and aerosol column number density. Monomodal aerosol size distribution is assumed. The Cost Function (CF radiance data at the TOA have been created assuming either one or two layers of aerosols using the vector is affected by the radiative forcing associated with various sources, including total solar irradiance

  10. Mixtures of pollution, dust, sea salt, and volcanic aerosol during ACE-Asia: Radiative properties

    E-Print Network [OSTI]

    was dominated by marine, polluted, volcanic, and dust aerosols. Average total light scattering coefficients (sspMixtures of pollution, dust, sea salt, and volcanic aerosol during ACE-Asia: Radiative properties). Aerosol hygroscopicity ranged from deliquescent with hysteresis (marine frequently and polluted variably

  11. Experience with Aerosol Generation During Rotary Mode Core Sampling in the Hanford Single Shell Waste Tanks

    SciTech Connect (OSTI)

    SCHOFIELD, J.S.

    2000-01-24

    This document provides data on aerosol concentrations in tank head spaces, total mass of aerosols in the tank head space and mass of aerosols sent to the exhauster during Rotary Mode Core Sampling from November 1994 through June 1999. A decontamination factor for the RMCS exhauster filter housing is calculated based on operation data.

  12. Atmospheric aerosols in Amazonia and land use change: from natural biogenic to biomass

    E-Print Network [OSTI]

    Atmospheric aerosols in Amazonia and land use change: from natural biogenic to biomass burning in Central Amazonia (TT34 North of Manaus) and at a heavily biomass burning impacted site in south-refractory PM1 aerosol loading at TT34, while biomass burning aerosols at PVH shows a 93% content of organic

  13. AEROSOL-CLOUD INTERACTIONS CONTROL OF EARTH RADIATION AND LATENT HEAT RELEASE BUDGETS

    E-Print Network [OSTI]

    Daniel, Rosenfeld

    AEROSOL-CLOUD INTERACTIONS CONTROL OF EARTH RADIATION AND LATENT HEAT RELEASE BUDGETS D. ROSENFELD simulations show that cloud development is strongly mod- ulated by the impact of cloud-aerosol interactions on precipitation forming processes. New insights into the mechanisms by which aerosols dominate the cloud cover

  14. Aerosols and Clouds: In Cahoots to Change Climate

    ScienceCinema (OSTI)

    Berg, Larry

    2014-06-02

    Key knowledge gaps persist despite advances in the scientific understanding of how aerosols and clouds evolve and affect climate. The Two-Column Aerosol Project, or TCAP, was designed to provide a detailed set of observations to tackle this area of unknowns. Led by PNNL atmospheric scientist Larry Berg, ARM's Climate Research Facility was deployed in Cape Cod, Massachusetts for the 12-month duration of TCAP, which came to a close in June 2013. "We are developing new tools to look at particle chemistry, like our mass spectrometer used in TCAP that can tell us the individual chemical composition of an aerosol," said Berg. "Then, we'll run our models and compare it with the data that we have to make sure we're getting correct answers and make sure our climate models are reflecting the best information."

  15. Speciation of Fe in ambient aerosol and cloudwater

    SciTech Connect (OSTI)

    Siefert, L. [California Institute of Technology, Pasadena, CA (United States)

    1996-08-15

    Atmospheric iron (Fe) is thought to play an important role in cloudwater chemistry (e.g., S(IV) oxidation, oxidant production, etc.), and is also an important source of Fe to certain regions of the worlds oceans where Fe is believed to be a rate-limiting nutrient for primary productivity. This thesis focuses on understanding the chemistry, speciation and abundance of Fe in cloudwater and aerosol in the troposphere, through observations of Fe speciation in the cloudwater and aerosol samples collected over the continental United States and the Arabian Sea. Different chemical species of atmospheric Fe were measured in aerosol and cloudwater samples to help assess the role of Fe in cloudwater chemistry.

  16. Aerosols and Clouds: In Cahoots to Change Climate

    SciTech Connect (OSTI)

    Berg, Larry

    2014-03-29

    Key knowledge gaps persist despite advances in the scientific understanding of how aerosols and clouds evolve and affect climate. The Two-Column Aerosol Project, or TCAP, was designed to provide a detailed set of observations to tackle this area of unknowns. Led by PNNL atmospheric scientist Larry Berg, ARM's Climate Research Facility was deployed in Cape Cod, Massachusetts for the 12-month duration of TCAP, which came to a close in June 2013. "We are developing new tools to look at particle chemistry, like our mass spectrometer used in TCAP that can tell us the individual chemical composition of an aerosol," said Berg. "Then, we'll run our models and compare it with the data that we have to make sure we're getting correct answers and make sure our climate models are reflecting the best information."

  17. Distinguishing Aerosol Impacts on Climate Over the Past Century

    SciTech Connect (OSTI)

    Koch, Dorothy; Menon, Surabi; Del Genio, Anthony; Ruedy, Reto; Alienov, Igor; Schmidt, Gavin A.

    2008-08-22

    Aerosol direct (DE), indirect (IE), and black carbon-snow albedo (BAE) effects on climate between 1890 and 1995 are compared using equilibrium aerosol-climate simulations in the Goddard Institute for Space Studies General Circulation Model coupled to a mixed layer ocean. Pairs of control(1890)-perturbation(1995) with successive aerosol effects allow isolation of each effect. The experiments are conducted both with and without concurrent changes in greenhouse gases (GHG's). A new scheme allowing dependence of snow albedo on black carbon snow concentration is introduced. The fixed GHG experiments global surface air temperature (SAT) changed -0.2, -1.0 and +0.2 C from the DE, IE, and BAE. Ice and snow cover increased 1.0% from the IE and decreased 0.3% from the BAE. These changes were a factor of 4 larger in the Arctic. Global cloud cover increased by 0.5% from the IE. Net aerosol cooling effects are about half as large as the GHG warming, and their combined climate effects are smaller than the sum of their individual effects. Increasing GHG's did not affect the IE impact on cloud cover, however they decreased aerosol effects on SAT by 20% and on snow/ice cover by 50%; they also obscure the BAE on snow/ice cover. Arctic snow, ice, cloud, and shortwave forcing changes occur mostly during summer-fall, but SAT, sea level pressure, and long-wave forcing changes occur during winter. An explanation is that aerosols impact the cryosphere during the warm-season but the associated SAT effect is delayed until winter.

  18. Optics and Optical Engineering Program Assessment Plan Program Learning Objectives

    E-Print Network [OSTI]

    Cantlon, Jessica F.

    Optics and Optical Engineering Program Assessment Plan Program Learning, and processes that underlie optics and optical engineering. 2. Strong understanding of the fundamental science, mathematics, and processes that underlie optics and optical

  19. Sources and composition of submicron organic mass in marine aerosol particles: Marine Aerosol Organic Mass Composition

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Frossard, Amanda A.; Russell, Lynn M.; Burrows, Susannah M.; Elliott, Scott M.; Bates, Timothy S.; Quinn, Patricia K.

    2014-11-26

    Recent studies have proposed a variety of interpretations of the sources and composition of atmospheric marine aerosol particles (aMA) based on a range of physical and chemical measurements collected during open-ocean research cruises. To investigate the processes that affect marine organic particles, this study uses the characteristic functional group composition (from Fourier transform infrared (FTIR) spectroscopy) of aMAP from five ocean regions to show that: (i) The organic functional group composition of aMAP that can be identified as atmospheric primary marine (ocean-derived) aerosol (aPMA) is 65±12% hydroxyl, 21±9% alkane, 6±6% amine, and 7±8% carboxylic acid functional groups. Contributions from photochemicalmore »reactions add carboxylic acid groups (15%-25%), shipping effluent in seawater and ship emissions add additional alkane groups (up to 70%), and coastal emissions mix in alkane and carboxylic acid groups from coastal pollution sources. (ii) The organic composition of aPMA is nearly identical to model generated primary marine aerosol particles (gPMA) from bubbled seawater (55% hydroxyl, 32% alkane, and 13% amine functional groups), indicating that its overall functional group composition is the direct consequence of the organic constituents of the seawater source. (iii) While the seawater organic functional group composition was nearly invariant across all three ocean regions studied, the gPMA alkane group fraction increased with chlorophyll-a concentrations (r = 0.79). gPMA from productive seawater had a larger fraction of alkane functional groups (35%) compared to gPMA from non-productive seawater (16%), likely due to the presence of surfactants in productive seawater that stabilize the bubble film and lead to preferential drainage of the more soluble (lower alkane group fraction) organic components. gPMA has a hydroxyl group absorption peak location characteristic of monosaccharides and disaccharides, where the seawater OM hydroxyl group peak location is closer to that of polysaccharides. This may result from the larger saccharides preferentially remaining in the seawater during gPMA and aPMA production« less

  20. Sources and composition of submicron organic mass in marine aerosol particles: Marine Aerosol Organic Mass Composition

    SciTech Connect (OSTI)

    Frossard, Amanda A. [Univ. of California, San Diego, CA (United States). Scripps Inst. of Oceanography; Russell, Lynn M. [Univ. of California, San Diego, CA (United States). Scripps Inst. of Oceanography; Burrows, Susannah M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Atmospheric Science and Global Change Div. (ASGC); Elliott, Scott M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bates, Timothy S. [National Oceanic and Atmospheric Administration (NOAA), Seattle, WA (United States). Pacific Marine Environmental Lab. (PMEL); Quinn, Patricia K. [National Oceanic and Atmospheric Administration (NOAA), Seattle, WA (United States). Pacific Marine Environmental Lab. (PMEL)

    2014-11-26

    Recent studies have proposed a variety of interpretations of the sources and composition of atmospheric marine aerosol particles (aMA) based on a range of physical and chemical measurements collected during open-ocean research cruises. To investigate the processes that affect marine organic particles, this study uses the characteristic functional group composition (from Fourier transform infrared (FTIR) spectroscopy) of aMAP from five ocean regions to show that: (i) The organic functional group composition of aMAP that can be identified as atmospheric primary marine (ocean-derived) aerosol (aPMA) is 65±12% hydroxyl, 21±9% alkane, 6±6% amine, and 7±8% carboxylic acid functional groups. Contributions from photochemical reactions add carboxylic acid groups (15%-25%), shipping effluent in seawater and ship emissions add additional alkane groups (up to 70%), and coastal emissions mix in alkane and carboxylic acid groups from coastal pollution sources. (ii) The organic composition of aPMA is nearly identical to model generated primary marine aerosol particles (gPMA) from bubbled seawater (55% hydroxyl, 32% alkane, and 13% amine functional groups), indicating that its overall functional group composition is the direct consequence of the organic constituents of the seawater source. (iii) While the seawater organic functional group composition was nearly invariant across all three ocean regions studied, the gPMA alkane group fraction increased with chlorophyll-a concentrations (r = 0.79). gPMA from productive seawater had a larger fraction of alkane functional groups (35%) compared to gPMA from non-productive seawater (16%), likely due to the presence of surfactants in productive seawater that stabilize the bubble film and lead to preferential drainage of the more soluble (lower alkane group fraction) organic components. gPMA has a hydroxyl group absorption peak location characteristic of monosaccharides and disaccharides, where the seawater OM hydroxyl group peak location is closer to that of polysaccharides. This may result from the larger saccharides preferentially remaining in the seawater during gPMA and aPMA production

  1. Final Project Report - ARM CLASIC CIRPAS Twin Otter Aerosol

    SciTech Connect (OSTI)

    John A. Ogren

    2010-04-05

    The NOAA/ESRL/GMD aerosol group made three types of contributions related to airborne measurements of aerosol light scattering and absorption for the Cloud and Land Surface Interaction Campaign (CLASIC) in June 2007 on the Twin Otter research airplane operated by the Center for Interdisciplinary Remotely-Piloted Aircraft Studies (CIRPAS). GMD scientists served as the instrument mentor for the integrating nephelometer and particle soot absorption photometer (PSAP) on the Twin Otter during CLASIC, and were responsible for (1) instrument checks/comparisons; (2) instrument trouble shooting/repair; and (3) data quality control (QC) and submittal to the archive.

  2. Thermophoretic separation of aerosol particles from a sampled gas stream

    DOE Patents [OSTI]

    Postma, A.K.

    1984-09-07

    This disclosure relates to separation of aerosol particles from gas samples withdrawn from within a contained atmosphere, such as containment vessels for nuclear reactors or other process equipment where remote gaseous sampling is required. It is specifically directed to separation of dense aerosols including particles of any size and at high mass loadings and high corrosivity. The United States Government has rights in this invention pursuant to Contract DE-AC06-76FF02170 between the US Department of Energy and Westinghouse Electric Corporation.

  3. Thermophoretic separation of aerosol particles from a sampled gas stream

    DOE Patents [OSTI]

    Postma, Arlin K. (Halfway, OR)

    1986-01-01

    A method for separating gaseous samples from a contained atmosphere that includes aerosol particles uses the step of repelling particles from a gas permeable surface or membrane by heating the surface to a temperature greater than that of the surrounding atmosphere. The resulting thermophoretic forces maintain the gas permeable surface clear of aerosol particles. The disclosed apparatus utilizes a downwardly facing heated plate of gas permeable material to combine thermophoretic repulsion and gravity forces to prevent particles of any size from contacting the separating plate surfaces.

  4. Optical microphone

    DOE Patents [OSTI]

    Veligdan, James T. (Manorville, NY)

    2000-01-11

    An optical microphone includes a laser and beam splitter cooperating therewith for splitting a laser beam into a reference beam and a signal beam. A reflecting sensor receives the signal beam and reflects it in a plurality of reflections through sound pressure waves. A photodetector receives both the reference beam and reflected signal beam for heterodyning thereof to produce an acoustic signal for the sound waves. The sound waves vary the local refractive index in the path of the signal beam which experiences a Doppler frequency shift directly analogous with the sound waves.

  5. Optical microfluidics

    SciTech Connect (OSTI)

    Kotz, K.T.; Noble, K.A.; Faris, G.W. [Molecular Physics Laboratory, SRI International, 333 Ravenswood Avenue, Menlo Park, California 94025 (United States)

    2004-09-27

    We present a method for the control of small droplets based on the thermal Marangoni effect using laser heating. With this approach, droplets covering five orders of magnitude in volume ({approx}1.7 {mu}L to 14 pL), immersed in decanol, were moved on an unmodified polystyrene surface, with speeds of up to 3 mm/s. When two droplets were brought into contact, they spontaneously fused and rapidly mixed in less than 33 ms. This optically addressed microfluidic approach has many advantages for microfluidic transport, including exceptional reconfigurability, low intersample contamination, large volume range, extremely simple substrates, no electrical connections, and ready scaling to large arrays.

  6. Optical devices

    DOE Patents [OSTI]

    Chaves, Julio C.; Falicoff, Waqidi; Minano, Juan C.; Benitez, Pablo; Dross, Oliver; Parkyn, Jr., William A.

    2010-07-13

    An optical manifold for efficiently combining a plurality of blue LED outputs to illuminate a phosphor for a single, substantially homogeneous output, in a small, cost-effective package. Embodiments are disclosed that use a single or multiple LEDs and a remote phosphor, and an intermediate wavelength-selective filter arranged so that backscattered photoluminescence is recycled to boost the luminance and flux of the output aperture. A further aperture mask is used to boost phosphor luminance with only modest loss of luminosity. Alternative non-recycling embodiments provide blue and yellow light in collimated beams, either separately or combined into white.

  7. Optical storage with electromagnetically induced transparency in a dense cold atomic ensemble

    E-Print Network [OSTI]

    Du, Shengwang

    Optical storage with electromagnetically induced transparency in a dense cold atomic ensemble storage with electromagnetically induced transparency in a dense cold 85 Rb atomic ensemble. By varying the optical depth (OD) from 0 to 140, we observe that the optimal storage effi- ciency has a saturation value

  8. Infrared cloud imaging in support of Earth-space optical communication

    E-Print Network [OSTI]

    Shaw, Joseph A.

    Infrared cloud imaging in support of Earth- space optical communication Paul W. Nugent,1 Joseph A to the communication platform, so there is a need to measure spatial and temporal statistics of clouds at potential to provide continuous day-night cloud detection and classification according to the cloud optical depth

  9. Optical sedimentation recorder

    DOE Patents [OSTI]

    Bishop, James K.B.

    2014-05-06

    A robotic optical sedimentation recorder is described for the recordation of carbon flux in the oceans wherein both POC and PIC particles are captured at the open end of a submersible sampling platform, the captured particles allowed to drift down onto a collection plate where they can be imaged over time. The particles are imaged using three separate light sources, activated in sequence, one source being a back light, a second source being a side light to provide dark field illumination, and a third source comprising a cross polarized light source to illuminate birefringent particles. The recorder in one embodiment is attached to a buoyancy unit which is capable upon command for bringing the sedimentation recorder to a programmed depth below the ocean surface during recordation mode, and on command returning the unit to the ocean surface for transmission of recorded data and receipt of new instructions. The combined unit is provided with its own power source and is designed to operate autonomously in the ocean for extended periods of time.

  10. ARM: 10-minute TEMPORARY Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    2010-12-15

    10-minute TEMPORARY Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  11. ARM: 10-minute TEMPORARY Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    10-minute TEMPORARY Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  12. 350-?m side-view optical probe for imaging the murine brain in vivo from the cortex to the hypothalamus

    E-Print Network [OSTI]

    Kim, Jun Ki

    Miniature endoscopic probes offer a solution for deep brain imaging by overcoming the limited depth of intravital microscopy. We describe a small-diameter (350 ?m) graded-index optical probe with a side-view design for in ...

  13. RFID tag modification for full depth backscatter modulation

    DOE Patents [OSTI]

    Scott, Jeffrey Wayne [Pasco, WA; Pratt, Richard M [Richland, WA

    2010-07-20

    A modulated backscatter radio frequency identification device includes a diode detector configured to selectively modulate a reply signal onto an incoming continuous wave; communications circuitry configured to provide a modulation control signal to the diode detector, the diode detector being configured to modulate the reply signal in response to be modulation control signal; and circuitry configured to increase impedance change at the diode detector which would otherwise not occur because the diode detector rectifies the incoming continuous wave while modulating the reply signal, whereby reducing the rectified signal increases modulation depth by removing the reverse bias effects on impedance changes. Methods of improving depth of modulation in a modulated backscatter radio frequency identification device are also provided.

  14. Analysis of Proper Depth for Gaining Seawater Heat

    E-Print Network [OSTI]

    and seawater temperatures near the city. · It is impossible to get deep sea water for Busan area, since according to the season, while that of deep sea water is constant. Point 1 207 Area 0.00 5.00 10.00 15.00 20 the maximum sea water depth around Busan is about 150m. · It will be a good option to use surface layer water

  15. A depth-derived Pleistocene age model: Uncertainty estimates, sedimentation variability, and nonlinear climate change

    E-Print Network [OSTI]

    Wunsch, Carl

    A depth-derived Pleistocene age model: Uncertainty estimates, sedimentation variability. To avoid biasing this ``depth-derived'' age estimate, the depth scale is first corrected for the effects sediment accumulation rates are estimated and modeled as an autocorrelated stochastic process. Depth-derived

  16. Lubricating Oil Dominates Primary Organic Aerosol Emissions from Motor Vehicles

    E-Print Network [OSTI]

    Goldstein, Allen

    Lubricating Oil Dominates Primary Organic Aerosol Emissions from Motor Vehicles David R. Worton to "fresh" lubricating oil. The gas chromatography retention time data indicates that the cycloalkane ring with lubricating oil being the dominant source from both gasoline and diesel-powered vehicles, with an additional

  17. Reduction of photosynthetically active radiation under extreme stratospheric aerosol loads

    SciTech Connect (OSTI)

    Gerstl, S.A.W.; Zardecki, A.

    1981-08-01

    The recently published hypothesis that the Cretaceous-Tertiary extinctions might be caused by an obstruction of sunlight is tested by model calculations. First we compute the total mass of stratospheric aerosols under normal atmospheric conditions for four different (measured) aerosol size distributions and vertical profiles. For comparison, the stratospheric dust masses after four volcanic eruptions are also evaluated. Detailed solar radiative transfer calculations are then performed for artificially increased aerosol amounts until the postulated darkness scenario is obtained. Thus we find that a total stratospheric aerosol mass between 1 and 4 times 10/sup 1/ g is sufficient to reduce photosynthesis to 10/sup -3/ of normal. We also infer from this result tha the impact of a 0.4- to 3-km-diameter asteroid or a close encounter with a Halley-size comet may deposit that amount of particulates into the stratosphere. The darkness scenario of Alvarez et al. is thus shown to be a possible extinction mechanism, even with smaller size asteroids of comets than previously estimated.

  18. Detection of UV-absorbing aerosols using GOME and SCIAMACHY

    E-Print Network [OSTI]

    Graaf, Martin de

    using GOME and SCIAMACHY · Conclusions and Outlook #12;Last step: Only positive residues are considered-Adding KNMI Radiative Transfer Model Solar zenith angle = 30° Viewing zenith angle = 0° Surface albedo = 5% #12; Reflectance at TOA with absorbing aerosols Doubling-Adding KNMI Radiative Transfer Model Solar

  19. The coupling of winds, aerosols and chemistry in Titan's atmosphere

    E-Print Network [OSTI]

    Hourdin, Chez Frédéric

    REVIEW The coupling of winds, aerosols and chemistry in Titan's atmosphere BY SEBASTIEN LEBONNOIS 1'Ae´ronomie, IPSL, CNRS, BP3, 91371 Verrie`res le Buisson, France The atmosphere of Titan is a complex system, where the observed atmospheric structure of Titan's lower atmosphere (mainly in the stratosphere and troposphere

  20. Soft ionization of thermally evaporated hypergolic ionic liquid aerosols

    SciTech Connect (OSTI)

    University of California; ERC, Incorporated, Edwards Air Force Base; Air Force Research Laboratory, Edwards Air Force Base; National Synchrotron Radiation Research Center; Koh, Christine J.; Liu, Chen-Lin; Harmon, Christopher W.; Strasser, Daniel; Golan, Amir; Kostko, Oleg; Chambreau, Steven D.; L.Vaghjiani, Ghanshyam; Leone, Stephen R.

    2012-03-16

    Isolated ion pairs of a conventional ionic liquid, 1-Ethyl-3-Methyl-Imidazolium Bis(trifluoromethylsulfonyl)imide ([Emim+][Tf2N?]), and a reactive hypergolic ionic liquid, 1- Butyl-3-Methyl-Imidazolium Dicyanamide ([Bmim+][Dca?]), are generated by vaporizing ionic liquid submicron aerosol particles for the first time; the vaporized species are investigated by dissociative ionization with tunable vacuum ultraviolet (VUV) light, exhibiting clear intact cations, Emim+ and Bmim+, presumably originating from intact ion pairs. Mass spectra of ion pair vapor from an effusive source of the hypergolic ionic liquid show substantial reactive decomposition due to the internal energy of the molecules emanating from the source. Photoionization efficiency curves in the near threshold ionization region of isolated ion pairs of [Emim+][Tf2N?] ionic liquid vapor are compared for an aerosol source and an effusive source, revealing changes in the appearance energy due to the amount of internal energy in the ion pairs. The aerosol source has a shift to higher threshold energy (~;;0.3 eV), attributed to reduced internal energy of the isolated ion pairs. The method of ionic liquid submicron aerosol particle vaporization, for reactive ionic liquids such as hypergolic species, is a convenient, thermally ?cooler? source of isolated intact ion pairs in the gas phase compared to effusive sources.

  1. Soft ionization of thermally evaporated hypergolic ionic liquid aerosols

    SciTech Connect (OSTI)

    University of California; ERC, Incorporated, Edwards Air Force Base; Air Force Research Laboratory, Edwards Air Force Base; National Synchrotron Radiation Research Center; Institute of Chemistry, Hebrew University; Koh, Christine J.; Liu, Chen-Lin; Harmon, Christopher W.; Strasser, Daniel; Golan, Amir; Kostko, Oleg; Chambreau, Steven D.; Vaghjiani, Ghanshyam L.; Leone, Stephen R.

    2011-07-19

    Isolated ion pairs of a conventional ionic liquid, 1-Ethyl-3-Methyl-Imidazolium Bis(trifluoromethylsulfonyl)imide ([Emim+][Tf2N?]), and a reactive hypergolic ionic liquid, 1-Butyl-3-Methyl-Imidazolium Dicyanamide ([Bmim+][Dca?]), are generated by vaporizing ionic liquid submicron aerosol particles for the first time; the vaporized species are investigated by dissociative ionization with tunable vacuum ultraviolet (VUV) light, exhibiting clear intact cations, Emim+ and Bmim+, presumably originating from intact ion pairs. Mass spectra of ion pair vapor from an effusive source of the hypergolic ionic liquid show substantial reactive decomposition due to the internal energy of the molecules emanating from the source. Photoionization efficiency curves in the near threshold ionization region of isolated ion pairs of [Emim+][Tf2N?]ionic liquid vapor are compared for an aerosol source and an effusive source, revealing changes in the appearance energy due to the amount of internal energy in the ion pairs. The aerosol source has a shift to higher threshold energy (~;;0.3 eV), attributed to reduced internal energy of the isolated ion pairs. The method of ionic liquid submicron aerosol particle vaporization, for reactive ionic liquids such as hypergolic species, is a convenient, thermally ?cooler? source of isolated intact ion pairs in the gas phase compared to effusive sources.

  2. DIESEL AEROSOL SAMPLING METHODOLOGY -CRC E-43 EXECUTIVE SUMMARY

    E-Print Network [OSTI]

    Minnesota, University of

    ) was to develop Diesel aerosol sampling methods for the laboratory that would produce particle size distributions used to evaluate and select basic options, or to perform feasibility studies or preliminary assessments, and dilution with ambient air. A small amount of these nuclei mode particles contain solid ash from lube oil

  3. Black carbon aerosols and the third polar ice cap

    SciTech Connect (OSTI)

    Menon, Surabi; Koch, Dorothy; Beig, Gufran; Sahu, Saroj; Fasullo, John; Orlikowski, Daniel

    2010-04-15

    Recent thinning of glaciers over the Himalayas (sometimes referred to as the third polar region) have raised concern on future water supplies since these glaciers supply water to large river systems that support millions of people inhabiting the surrounding areas. Black carbon (BC) aerosols, released from incomplete combustion, have been increasingly implicated as causing large changes in the hydrology and radiative forcing over Asia and its deposition on snow is thought to increase snow melt. In India BC emissions from biofuel combustion is highly prevalent and compared to other regions, BC aerosol amounts are high. Here, we quantify the impact of BC aerosols on snow cover and precipitation from 1990 to 2010 over the Indian subcontinental region using two different BC emission inventories. New estimates indicate that Indian BC emissions from coal and biofuel are large and transport is expected to expand rapidly in coming years. We show that over the Himalayas, from 1990 to 2000, simulated snow/ice cover decreases by {approx}0.9% due to aerosols. The contribution of the enhanced Indian BC to this decline is {approx}36%, similar to that simulated for 2000 to 2010. Spatial patterns of modeled changes in snow cover and precipitation are similar to observations (from 1990 to 2000), and are mainly obtained with the newer BC estimates.

  4. Design of high efficiency blowers for future aerosol applications 

    E-Print Network [OSTI]

    Chadha, Raman

    2007-04-25

    High efficiency air blowers to meet future portable aerosol sampling applications were designed, fabricated, and evaluated. A Centrifugal blower was designed to achieve a flow rate of 100 L/min (1.67 x 10^-3 m^3/s) and a pressure rise of WC " 4...

  5. Aerosol Synthesis and Growth Mechanism of Magnetic Iron Nanoparticles

    E-Print Network [OSTI]

    rapidly over the past decades, such as mechanical milling, spray drying, sol-gel, sonochemistry, etcAerosol Synthesis and Growth Mechanism of Magnetic Iron Nanoparticles D. Kim1,a , E.S. Vasilieva2,b, evaporated and transported by carrier gas flow to the preliminary heated tubular furnace for decomposition

  6. Field Trial of an Aerosol-Based Enclosure Sealing Technology

    SciTech Connect (OSTI)

    Harrington, Curtis; Springer, David

    2015-09-01

    This report presents the results from several demonstrations of a new method for sealing building envelope air leaks using an aerosol sealing process developed by the Western Cooling Efficiency Center at UC Davis. The process involves pressurizing a building while applying an aerosol sealant to the interior. As air escapes through leaks in the building envelope, the aerosol particles are transported to the leaks where they collect and form a seal that blocks the leak. Standard blower door technology is used to facilitate the building pressurization, which allows the installer to track the sealing progress during the installation and automatically verify the final building tightness. Each aerosol envelope sealing installation was performed after drywall was installed and taped, and the process did not appear to interrupt the construction schedule or interfere with other trades working in the homes. The labor needed to physically seal bulk air leaks in typical construction will not be replaced by this technology. However, this technology is capable of bringing the air leakage of a building that was built with standard construction techniques and HERS-verified sealing down to levels that would meet DOE Zero Energy Ready Homes program requirements. When a developer is striving to meet a tighter envelope leakage specification, this technology could greatly reduce the cost to achieve that goal by providing a simple and relatively low cost method for reducing the air leakage of a building envelope with little to no change in their common building practices.

  7. AEROSOLS AND CLOUDS IN CHEMICAL TRANSPORT MODELS AND CLIMATE MODELS

    E-Print Network [OSTI]

    of Earth's climate system. Clouds are highly reflective in the solar spectrum, yet strongly absorbingAEROSOLS AND CLOUDS IN CHEMICAL TRANSPORT MODELS AND CLIMATE MODELS Ulrike Lohmann1 and Stephen E Forum: Perturbed Clouds in the Climate System, Frankfurt, Germany March 2-7, 2008 Environmental Sciences

  8. CLouds and Aerosol Radiative Interaction and Forcing Investigation

    E-Print Network [OSTI]

    Graaf, Martin de

    Radiative Interaction and Forcing Investigation Version 1.0 Date March 2012 Status Final #12;#12;CLARIFI, by absorbing and scattering solar radiation, and more importantly, by modifying cloud propertiesCLARIFI CLouds and Aerosol Radiative Interaction and Forcing Investigation M. de Graaf, L

  9. Halophilic Archaea determined from geothermal steam vent aerosols

    E-Print Network [OSTI]

    Kelley, Scott

    Halophilic Archaea determined from geothermal steam vent aerosols Dean G. Ellis, Richard W. Bizzoco Hydrothermal vents, known as `fumaroles', are ubiq- uitous features of geothermal areas. Although their geology contained halophilic Archaea closely related to the Haloarcula spp. found in non-geothermal salt mats

  10. LESSONS LEARNED IN AEROSOL MONITORING WITH THE RASA

    SciTech Connect (OSTI)

    Forrester, Joel B.; Bowyer, Ted W.; Carty, Fitz; Comes, Laura; Eslinger, Paul W.; Greenwood, Lawrence R.; Haas, Derek A.; Hayes, James C.; Kirkham, Randy R.; Lepel, Elwood A.; Litke, Kevin E.; Miley, Harry S.; Morris, Scott J.; Schrom, Brian T.; Van Davelaar, Peter; Woods, Vincent T.

    2011-09-14

    The Radionuclide Aerosol Sampler/Analyzer (RASA) is an automated aerosol collection and analysis system designed by Pacific Northwest National Laboratory (PNNL) in the 1990's and is deployed in several locations around the world as part of the International Monitoring System (IMS) required under the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The RASA operates unattended, save for regularly scheduled maintenance, iterating samples through a three-step process on a 24-hour interval. In its 15-year history, much has been learned from the operation and maintenance of the RASA that can benefit engineering updates or future aerosol systems. On 11 March 2011, a 9.0 magnitude earthquake and tsunami rocked the eastern coast of Japan, resulting in power loss and cooling failures at the Daiichi nuclear power plants in Fukushima Prefecture. Aerosol collections were conducted with the RASA in Richland, WA. We present a summary of the lessons learned over the history of the RASA, including lessons taken from the Fukushima incident, regarding the RASA IMS stations operated by the United States.

  11. Impact of anthropogenic absorbing aerosols on clouds and precipitation

    E-Print Network [OSTI]

    Impact of anthropogenic absorbing aerosols on clouds and precipitation: A review of recent and precipitation: A review of recent progresses Chien Wang Massachusetts Institute of Technology, E19-439K, 77 atmospheric circulation, and hence clouds and precipitation. Recent studies have suggested that the changes

  12. IMPACT OF AEROSOLS ON CONVECTIVE CLOUDS AND PRECIPITATION

    E-Print Network [OSTI]

    Zeng, Ning

    IMPACT OF AEROSOLS ON CONVECTIVE CLOUDS AND PRECIPITATION Wei-Kuo Tao,1 Jen-Ping Chen,2 Zhanqing Li effects on clouds could further extend to precipitation, both through the formation of cloud particles mechan- isms behind these effects, in particular, the ones connected to precipitation, are not yet well

  13. CLOUD DROPLET NUCLEATION AND ITS CONNECTION TO AEROSOL PROPERTIES

    E-Print Network [OSTI]

    influence the earth's radiation balance and climate directly, by scanering shortwave (solar) radiation in the earth radiation budget over the industrial period. exerting a radiative forcing that is of comparable. Keywords - Climate. aerosols. clouds, radiation INTRODUcnON In recent years awareness has increased

  14. Optical manifold

    DOE Patents [OSTI]

    Falicoff, Waqidi; Chaves, Julio C.; Minano, Juan Carlos; Benitez, Pablo; Dross, Oliver; Parkyn, Jr., William A.

    2010-02-23

    Optical systems are described that have at least one source of a beam of blue light with divergence under 15.degree.. A phosphor emits yellow light when excited by the blue light. A collimator is disposed with the phosphor and forms a yellow beam with divergence under 15.degree.. A dichroic filter is positioned to transmit the beam of blue light to the phosphor and to reflect the beam of yellow light to an exit aperture. In different embodiments, the beams of blue and yellow light are incident upon said filter with central angles of 15.degree., 22.degree., and 45.degree.. The filter may reflect all of one polarization and part of the other polarization, and a polarization rotating retroreflector may then be provided to return the unreflected light to the filter.

  15. The SLS optics beamline

    E-Print Network [OSTI]

    2006-01-01

    The SLS Optics Beamline U. Flechsig ? , R. Abela ? , R.in the ?eld of x-ray optics and synchrotron radiation in-radiation, beamline optics, channel cut monochromator,

  16. SURFACE NONLINEAR OPTICS

    E-Print Network [OSTI]

    Shen, Y.R.

    2010-01-01

    B. de Castro, and Y. R. Shen, Optics Lett. i, 393 See, for3, 1980 SURFACE NONLINEAR OPTICS Y.R. Shen, C.K. Chen, andde Janiero SURFRACE NONLINEAR OPTICS Y. R. Shen, C. K. Chen,

  17. NONLINEAR OPTICS AT INTERFACES

    E-Print Network [OSTI]

    Chen, Chenson K.

    2010-01-01

    N. Bloembergen, Nonlinear Optics (W. A. Benjamin, 1977) p.Research Division NONLINEAR OPTICS AT INTERFACES Chenson K.ED LBL-12084 NONLINEAR OPTICS AT INTERFACES Chenson K. Chen

  18. Chemical composition of dust storms in Beijing and implications for the mixing of mineral aerosol with pollution aerosol

    E-Print Network [OSTI]

    with pollution aerosol on the pathway Yele Sun,1 Guoshun Zhuang,1,2,3 Ying Wang,1 Xiujuan Zhao,1,4 Jie Li,5 Zifa direction could be seen as the ``polluted'' pathway and the north-northwesterly direction as the relatively ``less-polluted'' one. Dust storms not only delivered large amounts of mineral elements but also carried

  19. Chapter 2 Diffractive Optics

    E-Print Network [OSTI]

    2010-09-14

    Diffractive optics is an emerging technology with many applications. Some of the important applications include the design and fabrication of optical elements ...

  20. Advanced Optical Technologies

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    laser. Today, the optical team designs and fabricates a variety of custom diffractive optics for researchers worldwide. Included are multilayer dielectric and gold-overcoated...

  1. Planar micro-optic solar concentration

    E-Print Network [OSTI]

    Karp, Jason Harris

    2010-01-01

    Planar Micro-Optic Solar Collectors," Optics for Solarin planar micro-optic solar collectors,” Optics Express, (inin planar micro-optic solar collectors,” Optics Express (in

  2. FY 2011 Second Quarter: Demonstration of New Aerosol Measurement Verification Testbed for Present-Day Global Aerosol Simulations

    SciTech Connect (OSTI)

    Koch, D

    2011-03-20

    The regional-scale Weather Research and Forecasting (WRF) model is being used by a DOE Earth System Modeling (ESM) project titled “Improving the Characterization of Clouds, Aerosols and the Cryosphere in Climate Models” to evaluate the performance of atmospheric process modules that treat aerosols and aerosol radiative forcing in the Arctic. We are using a regional-scale modeling framework for three reasons: (1) It is easier to produce a useful comparison to observations with a high resolution model; (2) We can compare the behavior of the CAM parameterization suite with some of the more complex and computationally expensive parameterizations used in WRF; (3) we can explore the behavior of this parameterization suite at high resolution. Climate models like the Community Atmosphere Model version 5 (CAM5) being used within the Community Earth System Model (CESM) will not likely be run at mesoscale spatial resolutions (10–20 km) until 5–10 years from now. The performance of the current suite of physics modules in CAM5 at such resolutions is not known, and current computing resources do not permit high-resolution global simulations to be performed routinely. We are taking advantage of two tools recently developed under PNNL Laboratory Directed Research and Development (LDRD) projects for this activity. The first is the Aerosol Modeling Testbed (Fast et al., 2011b), a new computational framework designed to streamline the process of testing and evaluating aerosol process modules over a range of spatial and temporal scales. The second is the CAM5 suite of physics parameterizations that have been ported into WRF so that their performance and scale dependency can be quantified at mesoscale spatial resolutions (Gustafson et al., 2010; with more publications in preparation).

  3. Long-term impacts of aerosols on vertical development of cloud and precipitation

    SciTech Connect (OSTI)

    Li Z.; Liu Y.; Niu, F.; Fan, J.; Rosenfeld, D.; Ding, Y.

    2011-11-13

    Aerosols alter cloud density and the radiative balance of the atmosphere. This leads to changes in cloud microphysics and atmospheric stability, which can either suppress or foster the development of clouds and precipitation. The net effect is largely unknown, but depends on meteorological conditions and aerosol properties. Here, we examine the long-term impact of aerosols on the vertical development of clouds and rainfall frequencies, using a 10-year dataset of aerosol, cloud and meteorological variables collected in the Southern Great Plains in the United States. We show that cloud-top height and thickness increase with aerosol concentration measured near the ground in mixed-phase clouds-which contain both liquid water and ice-that have a warm, low base. We attribute the effect, which is most significant in summer, to an aerosol-induced invigoration of upward winds. In contrast, we find no change in cloud-top height and precipitation with aerosol concentration in clouds with no ice or cool bases. We further show that precipitation frequency and rain rate are altered by aerosols. Rain increases with aerosol concentration in deep clouds that have a high liquid-water content, but declines in clouds that have a low liquid-water content. Simulations using a cloud-resolving model confirm these observations. Our findings provide unprecedented insights of the long-term net impacts of aerosols on clouds and precipitation.

  4. Average Depth of Crude Oil and Natural Gas Wells

    Gasoline and Diesel Fuel Update (EIA)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustments (Billion Cubic Feet) Wyoming Dry Natural Gas ReservesAlabamaAboutTotal Energy GlossaryDepth of Crude

  5. EMSP Final Report: Electrically Driven Technologies for Radioactive Aerosol Abatement

    SciTech Connect (OSTI)

    DePaoli, D.W.

    2003-01-22

    The purpose of this research project was to develop an improved understanding of how electrically driven processes, including electrocoalescence, acoustic agglomeration, and electric filtration, may be employed to efficiently treat problems caused by the formation of aerosols during DOE waste treatment operations. The production of aerosols during treatment and retrieval operations in radioactive waste tanks and during thermal treatment operations such as calcination presents a significant problem of cost, worker exposure, potential for release, and increased waste volume. There was anecdotal evidence in the literature that acoustic agglomeration and electrical coalescence could be used together to change the size distribution of aerosol particles in such a way as to promote easier filtration and less frequent maintenance of filtration systems. As such, those electrically driven technologies could potentially be used as remote technologies for improved treatment; however, existing theoretical models are not suitable for prediction and design. To investigate the physics of such systems, and also to prototype a system for such processes, a collaborative project was undertaken between Oak Ridge National Laboratory (ORNL) and the University of Texas at Austin (UT). ORNL was responsible for the larger-scale prototyping portion of the project, while UT was primarily responsible for the detailed physics in smaller scale unit reactors. It was found that both electrical coalescence and acoustic agglomeration do in fact increase the rate of aggregation of aerosols. Electrical coalescence requires significantly less input power than acoustic agglomeration, but it is much less effective in its ability to aggregate/coalesce aerosols. The larger-scale prototype showed qualitatively similar results as the unit reactor tests, but presented more difficulty in interpretation of the results because of the complex multi-physics coupling that necessarily occur in all larger-scale system tests. An additional finding from this work is that low-amplitude oscillation may provide an alternative, non-invasive, non-contact means of controlling settling and/or suspension of solids. Further investigation would be necessary to evaluate its utility for radioactive waste treatment applications. This project did not uncover a new technology for radioactive waste treatment. While it may be possible that an efficient electrically driven technology for aerosol treatment could be developed, it appears that other technologies, such as steel and ceramic HEPA filters, can suitably solve this problem. If further studies are to be undertaken, additional fundamental experimentation and modeling is necessary to fully capture the physics; in addition, larger-scale tests are needed to demonstrate the treatment of flowing gas streams through the coupling of acoustic agglomeration with electrocoalescence.

  6. Measurements of the chemical, physical, and optical properties of single aerosol particles

    E-Print Network [OSTI]

    Moffet, Ryan Christopher

    2007-01-01

    Index and Density Analytical Chemistry 77, 6535-6541.mass spectrometer, Analytical Chemistry, 78 (24), 8281-8289,instrumentation, Analytical Chemistry, 77 (12), 3861-3885,

  7. Measurements of the chemical, physical, and optical properties of single aerosol particles

    E-Print Network [OSTI]

    Moffet, Ryan Christopher

    2007-01-01

    and M.J. Molina: Mexico City basin wind circulation duringDistinct wind convergence patterns in the Mexico City basinMexico City was strongly influenced by continually changing emission sources and strong winds

  8. Variability of aerosol optical properties derived from in situ aircraft measurements during ACE-Asia

    E-Print Network [OSTI]

    Clarke, Antony

    , and Cameron S. McNaughton Department of Oceanography, University of Hawaii, Honolulu, Hawaii, USA Received 29 and artifacts are characterized using in-flight measurements of particle-free air and measurements dominant components, fine-mode pollution and coarse-mode mineral dust, were observed to vary independently

  9. Correlations between Optical, Chemical and Physical Properties of Biomass Burn Aerosols

    E-Print Network [OSTI]

    2008-01-01

    laboratory measurements of biomass-burning emissions: 1.tar balls: Particles from biomass and biofuel burning, J.Eleuterio (2005), A review of biomass burning emissions part

  10. Study of formation and convective transport of aerosols using optical diagnostic technique 

    E-Print Network [OSTI]

    Kim, Tae-Kyun

    2004-09-30

    and commonly used in process industries. There are numerous reports stating that mist explosions formed from leakage cause disastrous accidents in process industries. For safety concerns, the characteristics of mist formation should be known in order to prevent...

  11. Preliminary Results of in-situ Measurements of Aerosol Optical and Water

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeedingProgram Guidelines This document w1.½tankSurface RadiationCashing inUptake

  12. LABORATORY I: GEOMETRIC OPTICS

    E-Print Network [OSTI]

    Minnesota, University of

    Lab I - 1 LABORATORY I: GEOMETRIC OPTICS In this lab, you will solve several problems related to the formation of optical images. Most of us have a great deal of experience with the formation of optical images this laboratory, you should be able to: · Describe features of real optical systems in terms of ray diagrams

  13. Campbell penetration depth in Fe-based superconductors

    SciTech Connect (OSTI)

    Prommapan, Plegchart

    2011-08-15

    A 'true' critical current density, j{sub c}, as opposite to commonly measured relaxed persistent (Bean) current, j{sub B}, was extracted from the Campbell penetration depth, {lambda}{sub c}(T,H) measured in single crystals of LiFeAs, and optimally electron-doped Ba(Fe{sub 0.954}Ni{sub 0.046}){sub 2}As{sub 2} (FeNi122). In LiFeAs, the effective pinning potential is nonparabolic, which follows from the magnetic field - dependent Labusch parameter {alpha}. At the equilibrium (upon field - cooling), {alpha}(H) is non-monotonic, but it is monotonic at a finite gradient of the vortex density. This behavior leads to a faster magnetic relaxation at the lower fields and provides a natural dynamic explanation for the fishtail (second peak) effect. We also find the evidence for strong pinning at the lower fields.The inferred field dependence of the pinning potential is consistent with the evolution from strong pinning, through collective pinning, and eventually to a disordered vortex lattice. The value of j{sub c}(2 K) {approx_equal} 1.22 x 10{sup 6} A/cm{sup 2} provide an upper estimate of the current carrying capability of LiFeAs. Overall, vortex behavior of almost isotropic, fully-gapped LiFeAs is very similar to highly anisotropic d-wave cuprate superconductors, the similarity that requires further studies in order to understand unconventional superconductivity in cuprates and pnictides. In addition to LiFeAs, we also report the magnetic penetration depth in BaFe{sub 2}As{sub 2} based superconductors including irradiation of FeNi122. In unirradiated FeNi122, the maximum critical current value is, j{sub c}(2K) {approx_equal} 3.3 x 10{sup 6} A/cm{sup 2}. The magnetic-dependent feature was observed near the transition temperature in FeTe{sub 0.53}Se{sub 0.47} and irradiated FeNi122. Because of this feature, further studies are required in order to properly calibrate the Campbell penetration depth. Finally, we detected the crossing between the magnetic penetration depth and London penetration depth in optimally hold-doped Ba{sub 0.6}K{sub 0.4}Fe{sub 2}As{sub 2} (BaK122) and isovalent doped BaFe{sub 2}(As{sub 0.7}P{sub 0.3}){sub 2} (BaP122). These phenomena probably coincide with anomalous Meissner effect reported in pnicitde superconductors [Prozorov et al. (2010b)] however more studies are needed in order to clarify this.

  14. Optical XOR gate

    DOE Patents [OSTI]

    Vawter, G. Allen

    2013-11-12

    An optical XOR gate is formed as a photonic integrated circuit (PIC) from two sets of optical waveguide devices on a substrate, with each set of the optical waveguide devices including an electroabsorption modulator electrically connected in series with a waveguide photodetector. The optical XOR gate utilizes two digital optical inputs to generate an XOR function digital optical output. The optical XOR gate can be formed from III-V compound semiconductor layers which are epitaxially deposited on a III-V compound semiconductor substrate, and operates at a wavelength in the range of 0.8-2.0 .mu.m.

  15. The impact of atmospheric aerosols on trace metal chemistry in open ocean surface seawater 3. Lead

    SciTech Connect (OSTI)

    Maring, H.B.; Duce, R.A. )

    1990-04-15

    Atmospheric aerosols collected at Enewetak Atoll in the tropical North Pacific were exposed to seawater in laboratory experiments to assess the impact of atmospheric aerosols on lead chemistry in surface seawater. The net atmospheric flux of soluble lead to the ocean is between 16 and 32 pmol cm{sup {minus}2}/yr at Enewetak. The stable lead isotopic composition of soluble aerosol lead indicates that it is of anthropogenic origin. Anthropogenic aerosol lead from Central and North America appears to be less soluble and/or to dissolve less rapidly than that from Asia. Dissolved organic matter and possibly lower pH appear to increase the nonaluminosilicate aerosol lead solubility and/or dissolution rate. The isotopic composition of lead in air, seawater and dry deposition suggests that after deposition in the ocean, nonaluminosilicate particulate lead can be reinjected into the atmosphere during sea salt aerosol production.

  16. Ultrathin Optical Panel And A Method Of Making An Ultrathin Optical Panel.

    DOE Patents [OSTI]

    Biscardi, Cyrus (Bellport, NY); Brewster, Calvin (North Patchoque, NY); DeSanto, Leonard (Patchoque, NY); Veligdan, James T. (Manorville, NY)

    2005-02-15

    An ultrathin optical panel, and a method of producing an ultrathin optical panel, are disclosed, including stacking a plurality of glass sheets, which sheets may be coated with a transparent cladding substance or may be uncoated, fastening together the plurality of stacked coated glass sheets using an epoxy or ultraviolet adhesive, applying uniform pressure to the stack, curing the stack, sawing the stack to form an inlet face on a side of the stack and an outlet face on an opposed side of the stack, bonding a coupler to the inlet face of the stack, and fastening the stack, having the coupler bonded thereto, within a rectangular housing having an open front which is aligned with the outlet face, the rectangular housing having therein a light generator which is optically aligned with the coupler. The light generator is preferably placed parallel to and proximate with the inlet face, thereby allowing for a reduction in the depth of the housing.

  17. Ultrathin optical panel and a method of making an ultrathin optical panel

    DOE Patents [OSTI]

    Biscardi, Cyrus (Bellport, NY); Brewster, Calvin (North Patchogue, NY); DeSanto, Leonard (Patchogue, NY); Veligdan, James T. (Manorville, NY)

    2002-01-01

    An ultrathin optical panel, and a method of producing an ultrathin optical panel, are disclosed, including stacking a plurality of glass sheets, which sheets may be coated With a transparent cladding substance or may be uncoated, fastening together the plurality of stacked coated glass sheets using an epoxy or ultraviolet adhesive, applying uniform pressure to the stack, curing the stack, sawing the stack to form an inlet face on a side of the stack and an outlet face on an opposed side of the stack, bonding a coupler to the inlet face of the stack, and fastening the stack, having the coupler bonded thereto, within a rectangular housing having an open front which is aligned with the outlet face, the rectangular housing having therein a light generator which is optically aligned with the coupler. The light generator is preferably placed parallel to and proximate with the inlet face, thereby allowing for a reduction in the depth of the housing.

  18. Ultrathin optical panel and a method of making an ultrathin optical panel

    DOE Patents [OSTI]

    Biscardi, Cyrus (Bellport, NY); Brewster, Calvin (North Patchogue, NY); DeSanto, Leonard (Patchogue, NY); Veligdan, James T. (Manorville, NY)

    2003-02-11

    An ultrathin optical panel, and a method of producing an ultrathin optical panel, are disclosed, including stacking a plurality of glass sheets, which sheets may be coated with a transparent cladding substance or may be uncoated, fastening together the plurality of stacked coated glass sheets using an epoxy or ultraviolet adhesive, applying uniform pressure to the stack, curing the stack, sawing the stack to form an inlet face on a side of the stack and an outlet face on an opposed side of the stack, bonding a coupler to the inlet face of the stack, and fastening the stack, having the coupler bonded thereto, within a rectangular housing having an open front which is aligned with the outlet face, the rectangular housing having therein a light generator which is optically aligned with the coupler. The light generator is preferably placed parallel to and proximate with the inlet face, thereby allowing for a reduction in the depth of the housing.

  19. Ultrathin optical panel and a method of making an ultrathin optical panel

    DOE Patents [OSTI]

    Biscardi, Cyrus (Bellport, NY); Brewster, Calvin (North Patchogue, NY); DeSanto, Leonard (Patchogue, NY); Veligdan, James T. (Manorville, NY)

    2001-10-09

    An ultrathin optical panel, and a method of producing an ultrathin optical panel, are disclosed, including stacking a plurality of glass sheets, which sheets may be coated with a transparent cladding substance or may be uncoated, fastening together the plurality of stacked coated glass sheets using an epoxy or ultraviolet adhesive, applying uniform pressure to the stack, curing the stack, sawing the stack to form an inlet face on a side of the stack and an outlet face on an opposed side of the stack, bonding a coupler to the inlet face of the stack, and fastening the stack, having the coupler bonded thereto, within a rectangular housing having an open front which is aligned with the outlet face, the rectangular housing having therein a light generator which is optically aligned with the coupler. The light generator is preferably placed parallel to and proximate with the inlet face, thereby allowing for a reduction in the depth of the housing.

  20. Ultrathin Optical Panel And A Method Of Making An Ultrathin Optical Panel.

    DOE Patents [OSTI]

    Biscardi, Cyrus (Bellport, NY); Brewster, Calvin (North Patchogue, NY); DeSanto, Leonard (Patchogue, NY); Veligdan, James T. (Manorville, NY)

    2005-05-17

    An ultrathin optical panel, and a method of producing an ultrathin optical panel, are disclosed, including stacking a plurality of glass sheets, which sheets may be coated with a transparent cladding substance or may be uncoated, fastening together the plurality of stacked coated glass sheets using an epoxy or ultraviolet adhesive, applying uniform pressure to the stack, curing the stack, sawing the stack to form an inlet face on a side of the stack and an outlet face on an opposed side of the stack, bonding a coupler to the inlet face of the stack, and fastening the stack, having the coupler bonded thereto, within a rectangular housing having an open front which is aligned with the outlet face, the rectangular housing having therein a light generator which is optically aligned with the coupler. The light generator is preferably placed parallel to and proximate with the inlet face, thereby allowing for a reduction in the depth of the housing.

  1. Optical characterization of gaps in directly bonded Si compound optics using infrared spectroscopy

    E-Print Network [OSTI]

    Gully-Santiago, Michael; White, Victor

    2015-01-01

    Silicon direct bonding offers flexibility in the design and development of Si optics by allowing manufacturers to combine subcomponents with a potentially lossless and mechanically stable interface. The bonding process presents challenges in meeting the requirements for optical performance because air gaps at the Si interface cause large Fresnel reflections. Even small (35 nm) gaps reduce transmission through a direct bonded Si compound optic by 4% at $\\lambda = 1.25 \\; \\mu$m at normal incidence. We describe a bond inspection method that makes use of precision slit spectroscopy to detect and measure gaps as small as 14 nm. Our method compares low finesse Fabry-P\\'{e}rot models to high precision measurements of transmission as a function of wavelength. We demonstrate the validity of the approach by measuring bond gaps of known depths produced by microlithography.

  2. Unintended consequences of atmospheric injection of sulphate aerosols.

    SciTech Connect (OSTI)

    Brady, Patrick Vane; Kobos, Peter Holmes; Goldstein, Barry

    2010-10-01

    Most climate scientists believe that climate geoengineering is best considered as a potential complement to the mitigation of CO{sub 2} emissions, rather than as an alternative to it. Strong mitigation could achieve the equivalent of up to -4Wm{sup -2} radiative forcing on the century timescale, relative to a worst case scenario for rising CO{sub 2}. However, to tackle the remaining 3Wm{sup -2}, which are likely even in a best case scenario of strongly mitigated CO{sub 2} releases, a number of geoengineering options show promise. Injecting stratospheric aerosols is one of the least expensive and, potentially, most effective approaches and for that reason an examination of the possible unintended consequences of the implementation of atmospheric injections of sulphate aerosols was made. Chief among these are: reductions in rainfall, slowing of atmospheric ozone rebound, and differential changes in weather patterns. At the same time, there will be an increase in plant productivity. Lastly, because atmospheric sulphate injection would not mitigate ocean acidification, another side effect of fossil fuel burning, it would provide only a partial solution. Future research should aim at ameliorating the possible negative unintended consequences of atmospheric injections of sulphate injection. This might include modeling the optimum rate and particle type and size of aerosol injection, as well as the latitudinal, longitudinal and altitude of injection sites, to balance radiative forcing to decrease negative regional impacts. Similarly, future research might include modeling the optimum rate of decrease and location of injection sites to be closed to reduce or slow rapid warming upon aerosol injection cessation. A fruitful area for future research might be system modeling to enhance the possible positive increases in agricultural productivity. All such modeling must be supported by data collection and laboratory and field testing to enable iterative modeling to increase the accuracy and precision of the models, while reducing epistemic uncertainties.

  3. Laboratory Testing of Aerosol for Enclosure Air Sealing

    SciTech Connect (OSTI)

    Harrington, C.; Modera, M.

    2012-05-01

    Space conditioning energy use can be significantly reduced by addressing uncontrolled infiltration and exfiltration through the envelope of a building. A process for improving the air tightness of a building envelope by sealing shell leaks with an aerosol sealing technology is presented. Both retrofit and new construction applications are possible through applying this process either in attics and crawlspaces or during rough-in stage.

  4. Characterising an Extractive Electrospray Ionisation (EESI) source for the online mass spectrometry analysis of organic aerosols

    E-Print Network [OSTI]

    Gallimore, Peter J.; Kalberer, Markus

    2013-05-28

    is dependent only on the mass of 23   aerosol and is independent of particle size. This again points to a mechanism where particles are fully 24   dissolved in the spray regardless of size. Large particles leave no undissolved “core”. Presumably 25   11... aerosol samples collected 8   onto filters or impactors.13 The disadvantage of offline techniques is that after an extended sample 9   collection period (typically hours) where the aerosol chemical composition may change due to 10   evaporation...

  5. Alveolar targeting of aerosol pentamidine. Toward a rational delivery system

    SciTech Connect (OSTI)

    Simonds, A.K.; Newman, S.P.; Johnson, M.A.; Talaee, N.; Lee, C.A.; Clarke, S.W. )

    1990-04-01

    Nebulizer systems that deposit a high proportion of aerosolized pentamidine on large airways are likely to be associated with marked adverse side effects, which may lead to premature cessation of treatment. We have measured alveolar deposition and large airway-related side effects (e.g., cough, breathlessness, and effect on pulmonary function) after aerosolization of 150 mg pentamidine isethionate labeled with {sup 99m}Tc-Sn-colloid. Nine patients with AIDS were studied using three nebulizer systems producing different droplet size profiles: the Acorn System 22, Respirgard II, and Respirgard II with the inspiratory baffle removed. Alveolar deposition was greatest and side effects least with the nebulizer producing the smallest droplet size profile (Respirgard II), whereas large airway-related side effects were prominent and alveolar deposition lowest with the nebulizer producing the largest droplet size (Acorn System 22). Values for alveolar deposition and adverse airway effects were intermediate using the Respirgard with inspiratory baffle removed, thus indicating the importance of the baffle valve in determining droplet size. Addition of a similar baffle valve to the Acorn System 22 produced a marked improvement in droplet size profile. Selection of a nebulizer that produces an optimal droplet size range offers the advantage of enhancing alveolar targeting of aerosolized pentamidine while reducing large airway-related side effects.

  6. High air volume to low liquid volume aerosol collector

    DOE Patents [OSTI]

    Masquelier, Donald A. (Tracy, CA); Milanovich, Fred P. (Lafayette, CA); Willeke, Klaus (Cincinnati, OH)

    2003-01-01

    A high air volume to low liquid volume aerosol collector. A high volume flow of aerosol particles is drawn into an annular, centripetal slot in a collector which directs the aerosol flow into a small volume of liquid pool contained is a lower center section of the collector. The annular jet of air impinges into the liquid, imbedding initially airborne particles in the liquid. The liquid in the pool continuously circulates in the lower section of the collector by moving to the center line, then upwardly, and through assistance by a rotating deflector plate passes back into the liquid at the outer area adjacent the impinging air jet which passes upwardly through the liquid pool and through a hollow center of the collector, and is discharged via a side outlet opening. Any liquid droplets escaping with the effluent air are captured by a rotating mist eliminator and moved back toward the liquid pool. The collector includes a sensor assembly for determining, controlling, and maintaining the level of the liquid pool, and includes a lower centrally located valve assembly connected to a liquid reservoir and to an analyzer for analyzing the particles which are impinged into the liquid pool.

  7. Vertically Loaded Anchor: Drag Coefficient, Fall Velocity, and Penetration Depth using Laboratory Measurements 

    E-Print Network [OSTI]

    Cenac, William

    2011-08-08

    The offshore oilfield industry is continuously developing unique and break-through technologies and systems to extract hydrocarbons from ever increasing ocean depths. Due to the extreme depths being explored presently, large anchors are being...

  8. A Convex Hull Peeling Depth Approach to Nonparametric Massive Multivariate Data

    E-Print Network [OSTI]

    Wolfe, Patrick J.

    A Convex Hull Peeling Depth Approach to Nonparametric Massive Multivariate Data Analysis) and Multivariate Data Analysis Definitions on CHP Data Depth (Ordering Multivariate Data) Quantiles and Density with CHP Multivariate Median Skewness and Kurtosis of a Multivariate Distribution Outlier Detection

  9. Seismic evidence for thermal runaway during intermediate-depth earthquake rupture

    E-Print Network [OSTI]

    Barrett, Sarah A.

    Intermediate-depth earthquakes occur at depths where temperatures and pressures exceed those at which brittle failure is expected. There are two leading candidates for the physical mechanism behind these earthquakes: ...

  10. Real time in situ detection of organic nitrates in atmospheric aerosols

    E-Print Network [OSTI]

    Rollins, Andrew W.

    2011-01-01

    +NO 3 reaction. Atmospheric Chemistry and Physics 2009, 9,radicals (NO 3 ). Atmospheric Chemistry and Physics 2008, 8,aerosol yields. Atmospheric Chemistry and Physics 2009, 9,

  11. New Chemical Aerosol Characterization Methods- Examples Using Agricultural and Urban Airborne Particulate Matter 

    E-Print Network [OSTI]

    Zhou, Lijun

    2010-10-12

    This study explored different chemical characterization methods of agricultural and urban airborne particulate matter. Three different field campaigns are discussed. For the agricultural aerosols, measurement of the chemical ...

  12. Do biomass burning aerosols intensify drought in equatorial Asia during El Niño?

    E-Print Network [OSTI]

    Tosca, M. G; Randerson, J. T; Zender, C. S; Flanner, M. G; Rasch, P. J

    2010-01-01

    fication of drought-induced biomass burning in Indonesiavariability in global biomass burning emissions from 1997 toChemistry and Physics Do biomass burning aerosols intensify

  13. X-RAY ABSORPTION SPECTROSCOPY FOR THE CHEMICAL CHARACTERIZATION OF ATMOSPHERIC AEROSOLS

    E-Print Network [OSTI]

    Jaklevic, J. M.

    2011-01-01

    aerosol samples and on fly ash samples obtained from powerMajor elements present in fly ash samples obtained both in-

  14. Atmospheric Measurements of Submicron Aerosols at the California-Mexico Border and in Houston, Texas 

    E-Print Network [OSTI]

    Levy, Misti E

    2013-04-29

    as the concentration of Mexico, the submicron aerosols are heavily influenced by vehicle emissions. We observe an average single scattering albedo of 0...

  15. Control Systems Cyber Security: Defense-in-Depth Strategies

    SciTech Connect (OSTI)

    Mark Fabro

    2007-10-01

    Information infrastructures across many public and private domains share several common attributes regarding IT deployments and data communications. This is particularly true in the control systems domain. A majority of the systems use robust architectures to enhance business and reduce costs by increasing the integration of external, business, and control system networks. However, multi-network integration strategies often lead to vulnerabilities that greatly reduce the security of an organization, and can expose mission-critical control systems to cyber threats. This document provides guidance and direction for developing ‘defense-in-depth’ strategies for organizations that use control system networks while maintaining a multi-tier information architecture that requires: • Maintenance of various field devices, telemetry collection, and/or industrial-level process systems • Access to facilities via remote data link or modem • Public facing services for customer or corporate operations • A robust business environment that requires connections among the control system domain, the external Internet, and other peer organizations.

  16. Control Systems Cyber Security:Defense in Depth Strategies

    SciTech Connect (OSTI)

    David Kuipers; Mark Fabro

    2006-05-01

    Information infrastructures across many public and private domains share several common attributes regarding IT deployments and data communications. This is particularly true in the control systems domain. A majority of the systems use robust architectures to enhance business and reduce costs by increasing the integration of external, business, and control system networks. However, multi-network integration strategies often lead to vulnerabilities that greatly reduce the security of an organization, and can expose mission-critical control systems to cyber threats. This document provides guidance and direction for developing ‘defense-in-depth’ strategies for organizations that use control system networks while maintaining a multi-tier information architecture that requires: Maintenance of various field devices, telemetry collection, and/or industrial-level process systems Access to facilities via remote data link or modem Public facing services for customer or corporate operations A robust business environment that requires connections among the control system domain, the external Internet, and other peer organizations.

  17. Gamma-ray irradiated polymer optical waveguides

    SciTech Connect (OSTI)

    Lai, C.-C.; Wei, T.-Y.; Chang, C.-Y.; Wang, W.-S.; Wei, Y.-Y.

    2008-01-14

    Optical waveguides fabricated by gamma-ray irradiation on polymer through a gold mask are presented. The gamma-ray induced index change is found almost linearly dependent on the dose of the irradiation. And the measured propagation losses are low enough for practical application. Due to the high penetrability of gamma ray, uniform refractive index change in depth can be easily achieved. Moreover, due to large-area printing, the uniformity of waveguide made by gamma-ray irradiation is much better than that by e-beam direct writing.

  18. Large-Scale Spray Releases: Additional Aerosol Test Results

    SciTech Connect (OSTI)

    Daniel, Richard C.; Gauglitz, Phillip A.; Burns, Carolyn A.; Fountain, Matthew S.; Shimskey, Rick W.; Billing, Justin M.; Bontha, Jagannadha R.; Kurath, Dean E.; Jenks, Jeromy WJ; MacFarlan, Paul J.; Mahoney, Lenna A.

    2013-08-01

    One of the events postulated in the hazard analysis for the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak event involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids that behave as a Newtonian fluid. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and in processing facilities across the DOE complex. To expand the data set upon which the WTP accident and safety analyses were based, an aerosol spray leak testing program was conducted by Pacific Northwest National Laboratory (PNNL). PNNL’s test program addressed two key technical areas to improve the WTP methodology (Larson and Allen 2010). The first technical area was to quantify the role of slurry particles in small breaches where slurry particles may plug the hole and prevent high-pressure sprays. The results from an effort to address this first technical area can be found in Mahoney et al. (2012a). The second technical area was to determine aerosol droplet size distribution and total droplet volume from prototypic breaches and fluids, including sprays from larger breaches and sprays of slurries for which literature data are mostly absent. To address the second technical area, the testing program collected aerosol generation data at two scales, commonly referred to as small-scale and large-scale testing. The small-scale testing and resultant data are described in Mahoney et al. (2012b), and the large-scale testing and resultant data are presented in Schonewill et al. (2012). In tests at both scales, simulants were used to mimic the relevant physical properties projected for actual WTP process streams.

  19. Small-Scale Spray Releases: Additional Aerosol Test Results

    SciTech Connect (OSTI)

    Schonewill, Philip P.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, G. N.; Mahoney, Lenna A.; Tran, Diana N.; Burns, Carolyn A.; Kurath, Dean E.

    2013-08-01

    One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. To expand the data set upon which the WTP accident and safety analyses were based, an aerosol spray leak testing program was conducted by Pacific Northwest National Laboratory (PNNL). PNNL’s test program addressed two key technical areas to improve the WTP methodology (Larson and Allen 2010). The first technical area was to quantify the role of slurry particles in small breaches where slurry particles may plug the hole and prevent high-pressure sprays. The results from an effort to address this first technical area can be found in Mahoney et al. (2012a). The second technical area was to determine aerosol droplet size distribution and total droplet volume from prototypic breaches and fluids, including sprays from larger breaches and sprays of slurries for which literature data are largely absent. To address the second technical area, the testing program collected aerosol generation data at two scales, commonly referred to as small-scale and large-scale. The small-scale testing and resultant data are described in Mahoney et al. (2012b) and the large-scale testing and resultant data are presented in Schonewill et al. (2012). In tests at both scales, simulants were used to mimic the relevant physical properties projected for actual WTP process streams.

  20. Improving Bulk Microphysics Parameterizations in Simulations of Aerosol Effects

    SciTech Connect (OSTI)

    Wang, Yuan; Fan, Jiwen; Zhang, Renyi; Leung, Lai-Yung R.; Franklin, Charmaine N.

    2013-06-05

    To improve the microphysical parameterizations for simulations of the aerosol indirect effect (AIE) in regional and global climate models, a double-moment bulk microphysical scheme presently implemented in the Weather Research and Forecasting (WRF) model is modified and the results are compared against atmospheric observations and simulations produced by a spectral bin microphysical scheme (SBM). Rather than using prescribed aerosols as in the original bulk scheme (Bulk-OR), a prognostic doublemoment aerosol representation is introduced to predict both the aerosol number concentration and mass mixing ratio (Bulk-2M). The impacts of the parameterizations of diffusional growth and autoconversion and the selection of the embryonic raindrop radius on the performance of the bulk microphysical scheme are also evaluated. Sensitivity modeling experiments are performed for two distinct cloud regimes, maritime warm stratocumulus clouds (SC) over southeast Pacific Ocean from the VOCALS project and continental deep convective clouds (DCC) in the southeast of China from the Department of Energy/ARM Mobile Facility (DOE/AMF) - China field campaign. The results from Bulk-2M exhibit a much better agreement in the cloud number concentration and effective droplet radius in both the SC and DCC cases with those from SBM and field measurements than those from Bulk-OR. In the SC case particularly, Bulk-2M reproduces the observed drizzle precipitation, which is largely inhibited in Bulk-OR. Bulk-2M predicts enhanced precipitation and invigorated convection with increased aerosol loading in the DCC case, consistent with the SBM simulation, while Bulk-OR predicts the opposite behaviors. Sensitivity experiments using four different types of autoconversion schemes reveal that the autoconversion parameterization is crucial in determining the raindrop number, mass concentration, and drizzle formation for warm 2 stratocumulus clouds. An embryonic raindrop size of 40 ?m is determined as a more realistic setting in the autoconversion parameterization. The saturation adjustment employed in calculating condensation/evaporation in the bulk scheme is identified as the main factor responsible for the large discrepancies in predicting cloud water in the SC case, suggesting that an explicit calculation of diffusion growth with predicted supersaturation is necessary for further improvements of the bulk microphysics scheme. Lastly, a larger rain evaporation rate below cloud is found in the bulk scheme in comparison to the SBM simulation, which could contribute to a lower surface precipitation in the bulk scheme.

  1. Kirchhoff prestack depth migration in orthorhombic velocity models with differently rotated tensors

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Kirchhoff prestack depth migration in orthorhombic velocity models with differently rotated tensors use the ray-based Kirchhoff prestack depth migration to calculate migrated sections in simple with a differently rotated tensor of elastic moduli. We apply the Kirchhoff prestack depth migration to single

  2. Kirchhoff prestack depth migration in 3-D models: Comparison of triclinic anisotropy

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Kirchhoff prestack depth migration in 3-D models: Comparison of triclinic anisotropy with simpler the Kirchhoff prestack depth migration to the calculation of migrated sections in 3-D simple anisotropic. We test Kirchhoff prestack depth migration in velocity models with different types of anisotropy

  3. Depth-domain processing of teleseismic receiver functions and generalized three-dimensional imaging

    E-Print Network [OSTI]

    Dueker, Ken

    by itself or as a part of depth migration, is usually used for noise suppression in teleseismic receiver generalize the pre-stack depth migration methodology by introducing numerous signal-enhancement schemes could be superior to record summation used in conventional depth migration. #12;3 Introduction

  4. Gaussian packet prestack depth migration Department of Geophysics, Faculty of Mathematics and Physics, Charles University,

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Gaussian packet prestack depth migration Karel #20; Z#19;a#20;cek Department of Geophysics, Faculty depth migration. The main advantage of our method over the methods based on Gaussian beams is a direct. Thus, the Gaussian packet prestack depth migration is especially suitable for a target-oriented imaging

  5. Kirchhoff prestack depth migration in velocity models with and without rotation of the tensor of

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Kirchhoff prestack depth migration in velocity models with and without rotation of the tensor the Kirchhoff prestack depth migration to calculate migrated images in simple anisotropic homogeneous velocity of the tensor of elastic moduli. We apply the Kirchhoff prestack depth migration to correct single

  6. Kirchhoff prestack depth migration in velocity models with and without vertical gradients

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Kirchhoff prestack depth migration in velocity models with and without vertical gradients-mail: bucha@seis.karlov.mff.cuni.cz Summary The Kirchhoff prestack depth migration is used to calculate. The bottom layer is isotropic and homogeneous. We apply the Kirchhoff prestack depth migration to both

  7. Kirchhoff prestack depth migration in velocity models with and without rotation of the tensor of

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Kirchhoff prestack depth migration in velocity models with and without rotation of the tensor-mail: bucha@seis.karlov.mff.cuni.cz Summary We use the Kirchhoff prestack depth migration to calculate is limited to P-waves. Keywords 3-D Kirchhoff prestack depth migration, anisotropic velocity model, rotation

  8. Kirchhoff prestack depth migration in triclinic velocity models with differently rotated tensors

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Kirchhoff prestack depth migration in triclinic velocity models with differently rotated tensors use the Kirchhoff prestack depth migration to calculate migrated sections in simple anisotropic rotations of the tensor of elastic moduli. We apply the Kirchhoff prestack depth migration to single- layer

  9. Gaussian packet pre--stack depth migration the Marmousi data Karel Zacek*, Department Geophysics, Faculty

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Gaussian packet pre--stack depth migration the Marmousi data Karel Zacek*, Department Geophysics--stack depth migration. method on Marmousi data (Versteeg & 1991). advantage over methods Gaussian beams. Thus, Gaussian packet pre--stack depth migration is especially suitable target--oriented imaging

  10. Gaussian packet prestack depth migration. Part 3: Simple 2-D models

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Gaussian packet prestack depth migration. Part 3: Simple 2-D models V#19;aclav Bucha Department Republic, E-mail: bucha@seis.karlov.m#11;.cuni.cz Summary Gaussian packet prestack depth migration is used. Keywords Gaussian packets, Gaussian beams, prestack depth migration, Gabor transform, 2-D velocity model

  11. Kirchhoff prestack depth migration in velocity models with and without gradients: Comparison

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Kirchhoff prestack depth migration in velocity models with and without gradients: Comparison@seis.karlov.mff.cuni.cz Summary We use the Kirchhoff prestack depth migration to calculate migrated sections in simple anisotropic is isotropic and homogeneous. We apply the Kirchhoff prestack depth migration to both heterogeneous

  12. Depths, migration rates and environmental associations of acoustic scattering layers in the Gulf of California

    E-Print Network [OSTI]

    Benoit-Bird, Kelly J.

    Depths, migration rates and environmental associations of acoustic scattering layers in the Gulf-surface layer with mean daytime bottom depth of 43740 m (night: 61738 m), and a main migrating layer with mean bottom depth of 333776 m (night: 54727 m). Diel vertical migration rates for dusk ascents reached

  13. EVALUATION OF ULTRASONIC SNOW DEPTH SENSORS FOR AUTOMATED SURFACE OBSERVING SYSTEMS (ASOS)

    E-Print Network [OSTI]

    i THESIS EVALUATION OF ULTRASONIC SNOW DEPTH SENSORS FOR AUTOMATED SURFACE OBSERVING SYSTEMS (ASOS PREPARED UNDER OUR SUPERVISION BY WENDY ANN BRAZENEC ENTITLED EVALUATION OF ULTRASONIC SNOW DEPTH SENSORS;iii ABSTRACT OF THESIS EVALUATION OF ULTRASONIC SNOW DEPTH SENSORS FOR AUTOMATED SURFACE OBSERVING

  14. PRACTICAL SNOW DEPTH SAMPLING AROUND SIX SNOW TELEMETRY (SNOTEL) STATIONS IN COLORADO AND WYOMING, UNITED STATES

    E-Print Network [OSTI]

    Anderson, Charles W.

    THESIS PRACTICAL SNOW DEPTH SAMPLING AROUND SIX SNOW TELEMETRY (SNOTEL) STATIONS IN COLORADO Laituri Mazdak Arabi #12;ii ABSTRACT PRACTICAL SNOW DEPTH SAMPLING AROUND SIX SNOW TELEMETRY (SNOTEL. These stations measure snow depth (SD), snow water equivalent (SWE), air temperature and precipitation. To assess

  15. Modeling soil depth from topographic and land cover attributes Teklu K. Tesfa,1

    E-Print Network [OSTI]

    Tarboton, David

    Modeling soil depth from topographic and land cover attributes Teklu K. Tesfa,1 David G. Tarboton,1 June 2009; published 29 October 2009. [1] Soil depth is an important input parameter in hydrological and ecological modeling. Presently, the soil depth data available in national soil databases (STATSGO and SSURGO

  16. Impacts of Shortwave Penetration Depth on Large-Scale Ocean Circulation and Heat Transport

    E-Print Network [OSTI]

    Gnanadesikan, Anand

    Impacts of Shortwave Penetration Depth on Large-Scale Ocean Circulation and Heat Transport COLM independent parameter- izations that use ocean color to estimate the penetration depth of shortwave radiation. This study offers a way to evaluate the changes in irradiance penetration depths in coupled ocean

  17. Chemical and Physical Properties of Atmospheric Aerosols (a) A Case Study in the Unique Properties of Agricultural Aerosols (b) The Role of Chemical Composition in Ice Nucleation during the Arctic Spring 

    E-Print Network [OSTI]

    Moon, Seong-Gi

    2011-08-08

    dataset is reported for these physical and chemical properties of agricultural aerosols appropriate for use in a site-specific emission inventory. The emission rate and transport of the aerosols are also discussed. In addition, mixing ratios of total...

  18. Latching micro optical switch

    DOE Patents [OSTI]

    Garcia, Ernest J; Polosky, Marc A

    2013-05-21

    An optical switch reliably maintains its on or off state even when subjected to environments where the switch is bumped or otherwise moved. In addition, the optical switch maintains its on or off state indefinitely without requiring external power. External power is used only to transition the switch from one state to the other. The optical switch is configured with a fixed optical fiber and a movable optical fiber. The movable optical fiber is guided by various actuators in conjunction with a latching mechanism that configure the switch in one position that corresponds to the on state and in another position that corresponds to the off state.

  19. Atmos. Chem. Phys., 11, 15811602, 2011 www.atmos-chem-phys.net/11/1581/2011/

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    processing of OA in NYC, likely involving both acid- base chemistry and photochemistry. In addition, analysis of air mass trajectories and satellite imagery of aerosol optical depth (AOD) indicates that the high

  20. Atmos. Chem. Phys., 14, 1149311523, 2014 www.atmos-chem-phys.net/14/11493/2014/

    E-Print Network [OSTI]

    Meskhidze, Nicholas

    regions and transported over oceans, and implications for satellite retrievals of aerosol optical depth A is seen in southern African savannah at Mongu (Zambia), with average midvisible SSA 0.85. Sites