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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

ARM - Measurement - Aerosol optical depth  

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

depth depth ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol optical depth A measure of how much light aerosols prevent from passing through a column of atmosphere. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments HSRL : High Spectral Resolution Lidar MPL : Micropulse Lidar MFRSR : Multifilter Rotating Shadowband Radiometer NIMFR : Normal Incidence Multifilter Radiometer Field Campaign Instruments AOS-PMFOV : Acoustical Optical Spectrometer-Photometer with Multiple

2

Hyperspectral Aerosol Optical Depths from TCAP Flights  

SciTech Connect (OSTI)

4STAR (Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research), the worlds 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 4STARs spatially-resolved high-frequency hyperspectral products as a reliable tool for climate studies and satellite validation.

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.

2013-11-13T23:59:59.000Z

3

ARM - Evaluation Product - Aerosol Optical Depths from SASHE  

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

ProductsAerosol Optical Depths from SASHE ProductsAerosol Optical Depths from SASHE Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Aerosol Optical Depths from SASHE Site(s) PVC SGP General Description The Shortwave Array Spectroradiometer Hemispheric (SASHE) is a ground-based instrument that measures both direct and diffuse shortwave irradiance. In this regard, the instrument is similar to the multifilter rotating shadowband radiometer (MFRSR)-an instrument that has been in the ARM Facility stable for more than 15 years. However, the two instruments differ significantly in wavelength resolution and range. In particular, the SASHE provides hyperspectral measurements from about 350 nm to 1700 nm at a wavelength resolution from 1 to several nanometers, while the MFRSR only

4

Correction to Hyperspectral Aerosol Optical Depths from TCAP Flights  

SciTech Connect (OSTI)

In the paper Hyperspectral aerosol optical depths from TCAP flights by Y. Shinozuka et al. (Journal of Geophysical Research: Atmospheres, 118, doi:10.1002/2013JD020596, 2013), Tables 1 and 2 were published with the column heads out of order. Tables 1 and 2 are published correctly here. The publisher regrets the error.

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.

2014-02-16T23:59:59.000Z

5

Project of Aerosol Optical Depth Change in South America  

E-Print Network [OSTI]

AerosolDepth Brazil Bolivia French Guiana Suriname Guyana Venezuela Colombia Ecuador Peru Chile Argentina Suriname Guyana Venezuela Colombia Ecuador Peru Chile Argentina Paraguay Uruguay #12;Statistics of Aerosol M ean D ec 01 to 06 Mean Month AerosolDepth Brazil Bolivia French Guiana Suriname Guyana Venezuela

Frank, Thomas D.

6

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

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

Analysis of Langley optical depth data, with aerosol and gas retrievals, Analysis of Langley optical depth data, with aerosol and gas retrievals, for the RSS 103 instrument in Barrow, Alaska Gianelli, Scott Columbia University - NASA/GISS Lacis, Andrew NASA/Goddard Institute for Space Studies Carlson, Barbara NASA/Goddard Institute for Space Studies Category: Aerosols Bimodal aerosol retrievals, and high-resolution retrevals of nitrogen dioxide, are performed on the Langley optical depth data from the RSS 103 device that was situated in Barrow, Alaska between March and August in 1999. The results show a higher fine mode aerosol optical depth on average than was retrieved by the RSS 102 at the SGP site. The seasonal cycle is also reversed with high values at Barrow occurring in the spring and low values in the summer. The fine mode effective radius also appears to

7

Climatology of aerosol optical depth in northcentral Oklahoma: 19922008  

E-Print Network [OSTI]

of aerosol models; for identification of aerosols from spe- cific events (e.g., the Central American fires Radiation Measurement Program central facility near Lamont, Oklahoma, since the fall of 1992. Most dimming; that is, the decrease in solar radiation reaching Earth's surface. Additionally, the wavelength

8

Aerosol radiative forcing and the accuracy of satellite aerosol optical depth retrieval  

E-Print Network [OSTI]

, New Mexico, USA Michael Mishchenko Goddard Institute for Space Studies, NASA, New York, New York, USA between t = 0.1 and t = 0.8. The Department of Energy research satellite instrument, the Multispectral [Hobbs et al., 1997]. The aerosols' direct effect involves their interaction with solar and terrestrial

9

Retrieval of Aerosol Optical Depth in Vicinity of Broken Clouds from Reflectance Ratios: Case Study  

SciTech Connect (OSTI)

A recently developed reflectance ratio (RR) method for the retrieval of aerosol optical depth (AOD) is evaluated using extensive airborne and ground-based data sets collected during the Cloud and Land Surface Interaction Campaign (CLASIC) and the Cumulus Humilis Aerosol Processing Study (CHAPS), which took place in June 2007 over the U.S. Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Southern Great Plains site. A detailed case study is performed for a field of single-layer shallow cumuli observed on June 12, 2007. The RR method is applied to retrieve the spectral values of AOD from the reflectance ratios measured by the MODIS Airborne Simulator (MAS) for two pairs of wavelengths (660 and 470 nm and 870 and 470 nm) collected at a spatial resolution of 0.05 km. The retrieval is compared with an independent AOD estimate from three ground-based Multi-filter Rotating Shadowband Radiometers (MFRSRs). The interpolation algorithm that is used to project MFRSR point measurements onto the aircraft flight tracks is tested using AOD derived from NASA Langley High Spectral Resolution Lidar (HSRL). The RR AOD estimates are in a good agreement (within 5%) with the MFRSR-derived AOD values for the 660-nm wavelength. The AODs obtained from MAS reflectance ratios overestimate those derived from MFRSR measurements by 15-30% for the 470-nm wavelength and underestimate the 870-nm AOD by the same amount.

Kassianov, Evgueni I.; Ovchinnikov, Mikhail; Berg, Larry K.; McFarlane, Sally A.; Flynn, Connor J.; Ferrare, Richard; Hostetler, Chris A.; Alexandrov, Mikhail

2010-10-06T23:59:59.000Z

10

Retrieval of Aerosol Optical Depth in Vicinity of Broken Clouds from Reflectance Ratios: Sensitivity Study  

SciTech Connect (OSTI)

We conducted a sensitivity study to better understand the potential of a new method for retrieving aerosol optical depth (AOD) under partly cloudy conditions. This method exploits reflectance ratios in the visible spectral range and provides an effective way to avoid three-dimensional (3D) cloud effects. The sensitivity study is performed for different observational conditions and random errors in input data. The results of the sensitivity study suggest that this ratio method has the ability to detect clear pixels even in close proximity to clouds. Such detection does not require a statistical analysis of the two-dimensional (2D) horizontal distribution of reflected solar radiation, and thus it could be customized for operational retrievals. In comparison with previously suggested approaches, the ratio method has the capability to increase the "harvest" of clear pixels. Similar to the traditional Independent Pixel Approximation (IPA), the ratio method has a low computational cost for retrieving AOD. In contrast to the IPA method, the ratio method provides much more accurate estimations of the AOD values under broken cloud conditions: pixel-based and domain-averaged estimations of errors in AOD are about 25% and 10%, respectively. Finally, both the ratio-based cloud screening and the accuracy of domain-averaged ratio-based AOD values do not suffer greatly when 5% random errors are introduced in the reflectances.

Kassianov, Evgueni I.; Ovtchinnikov, Mikhail; Berg, Larry K.; McFarlane, Sally A.; Flynn, Connor J.

2009-09-01T23:59:59.000Z

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)

Optical Depth Value-Added Product A Koontz C Flynn G Hodges J Michalsky J Barnard March 2013 DISCLAIMER This report was prepared as an account of work sponsored by the U.S....

12

Dust aerosol, clouds, and the atmospheric optical depth record over 5 Mars years of the Mars Exploration Rover mission  

E-Print Network [OSTI]

Dust aerosol plays a fundamental role in the behavior and evolution of the Martian atmosphere. The first five Mars years of Mars Exploration Rover data provide an unprecedented record of the dust load at two sites. This record is useful for characterization of the atmosphere at the sites and as ground truth for orbital observations. Atmospheric extinction optical depths have been derived from solar images after calibration and correction for time-varying dust that has accumulated on the camera windows. The record includes local, regional, and globally extensive dust storms. Comparison with contemporaneous thermal infrared data suggests significant variation in the size of the dust aerosols, with a 1 {\\mu}m effective radius during northern summer and a 2 {\\mu}m effective radius at the onset of a dust lifting event. The solar longitude (LS) 20-136{\\deg} period is also characterized by the presence of cirriform clouds at the Opportunity site, especially near LS=50 and 115{\\deg}. In addition to water ice clouds, ...

Lemmon, Mark T; Bell, James F; Smith, Michael D; Cantor, Bruce A; Smith, Peter H

2014-01-01T23:59:59.000Z

13

Atmospheric Aerosol Optical Properties in the Persian Gulf  

Science Journals Connector (OSTI)

Aerosol optical depth measurements over Bahrain acquired through the ground-based Aerosol Robotic Network (AERONET) are analyzed. Optical depths obtained from ground-based sun/sky radiometers showed a pronounced temporal trend, with a maximum ...

Alexander Smirnov; Brent N. Holben; Oleg Dubovik; Norm T. O'Neill; Thomas F. Eck; Douglas L. Westphal; Andreas K. Goroch; Christophe Pietras; Ilya Slutsker

2002-02-01T23:59:59.000Z

14

Spatial characteristics of the difference between MISR and MODIS aerosol optical depth retrievals over mainland Southeast Asia  

E-Print Network [OSTI]

autoregressive (SAR) model Spatial clustering Data assimilation Mainland Southeast Asia The difference between satellite, aerosol products generated using data from these two sensors often exhibit noticeable differences Resolution Imaging Spectroradiometer (MODIS) aboard the NASA Earth Observation System's Terra satellite

Shi, Tao

15

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

SciTech Connect (OSTI)

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, its 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.

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

2014-01-16T23:59:59.000Z

16

Geometrical Optics of Dense Aerosols  

SciTech Connect (OSTI)

Assembling a free-standing, sharp-edged slab of homogeneous material that is much denser than gas, but much more rare ed than a solid, is an outstanding technological challenge. The solution may lie in focusing a dense aerosol to assume this geometry. However, whereas the geometrical optics of dilute aerosols is a well-developed fi eld, the dense aerosol limit is mostly unexplored. Yet controlling the geometrical optics of dense aerosols is necessary in preparing such a material slab. Focusing dense aerosols is shown here to be possible, but the nite particle density reduces the eff ective Stokes number of the flow, a critical result for controlled focusing. __________________________________________________

Hay, Michael J.; Valeo, Ernest J.; Fisch, Nathaniel J.

2013-04-24T23:59:59.000Z

17

ARM - Measurement - Cloud optical depth  

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

optical depth optical depth ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Cloud optical depth Amount of light cloud droplets or ice particles prevent from passing through a column of atmosphere. Categories Cloud Properties Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. External Instruments GOES : Geostationary Operational Environmental Satellites Field Campaign Instruments EC-CONVAIR580-BULK : Environment Canada Convair 580 Bulk Parameters GOES : Geostationary Operational Environmental Satellites

18

Evolution of the optical properties of biomass-burning aerosol during the 2003 southeast Australian bushfires  

Science Journals Connector (OSTI)

During January and February 2003, drought conditions led to major bushfires across southeast Australia, causing considerable damage. We have examined aerosol optical depth (AOD) data...

Radhi, Majed; Box, Michael A; Box, Gail P; Gupta, Pawan; Christopher, Sundar A

2009-01-01T23:59:59.000Z

19

E-Print Network 3.0 - airborne aerosol prediction Sample Search...  

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

profiles of aerosol extinction and optical depth Evaluate predictions from aerosol transport... aerosol measurements. Comparison of AOT ... Source: Brookhaven National...

20

ARM - Measurement - Aerosol optical properties  

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

properties properties ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol optical properties The optical properties of aerosols, including asymmetry factor, phase-function, single-scattering albedo, refractive index, and backscatter fraction. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments CSPHOT : Cimel Sunphotometer NEPHELOMETER : Nephelometer Field Campaign Instruments AOS-PMFOV : Acoustical Optical Spectrometer-Photometer with Multiple

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

An Automated Method of MFRSR Calibration for Aerosol Optical Depth Analysis with Application to an Asian Dust Outbreak over the United States  

Science Journals Connector (OSTI)

Over the past decade, networks of Multifilter Rotating Shadowband Radiometers (MFRSR) and automated sun photometers have been established in the United States to monitor aerosol properties. The MFRSR alternately measures diffuse and global ...

John A. Augustine; Christopher R. Cornwall; Gary B. Hodges; Charles N. Long; Carlos I. Medina; John J. DeLuisi

2003-02-01T23:59:59.000Z

22

Optical, physical, and chemical properties of springtime aerosol...  

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

Optical, physical, and chemical properties of springtime aerosol over Barrow Alaska in 2008. Optical, physical, and chemical properties of springtime aerosol over Barrow Alaska in...

23

Determining Nighttime Atmospheric Optical Depth Using Mars Exploration Rover Images  

E-Print Network [OSTI]

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...

Bean, Keri Marie

2013-07-22T23:59:59.000Z

24

Tropospheric Aerosol Optical Thickness from the GOCART Model and Comparisons with Satellite and Sun Photometer Measurements  

Science Journals Connector (OSTI)

The Georgia Institute of TechnologyGoddard Global Ozone Chemistry Aerosol Radiation and Transport (GOCART) model is used to simulate the aerosol optical thickness ? for major types of tropospheric aerosols including sulfate, dust, organic carbon ...

Mian Chin; Paul Ginoux; Stefan Kinne; Omar Torres; Brent N. Holben; Bryan N. Duncan; Randall V. Martin; Jennifer A. Logan; Akiko Higurashi; Teruyuki Nakajima

2002-02-01T23:59:59.000Z

25

Assessing the Radiative Impact of Clouds of Low Optical Depth  

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

the Radiative Impact of Clouds of the Radiative Impact of Clouds of Low Optical Depth W. O'Hirok and P. Ricchiazzi Institute for Computational Earth System Science University of California Santa Barbara, California C. Gautier Department of Geography and Institute for Computational Earth System Science University of California Santa Barbara, California Introduction Analysis from the International Satellite Cloud Climatology Project (ISCCP) reveals that the global mean cloud optical depth is surprisingly low (i.e., τ = 3.8). While this value is probably dominated by extensive fields of cirrus, the average for liquid water clouds is also likely smaller than expected. It is in this regime (τ <10) where remote measurements of cloud optical thickness or liquid water path (LWP)

26

Eight-year Climatology of Dust Optical Depth on Mars  

E-Print Network [OSTI]

We have produced a multiannual climatology of airborne dust from Martian year 24 to 31 using multiple datasets of retrieved or estimated column optical depths. The datasets are based on observations of the Martian atmosphere from April 1999 to July 2013 made by different orbiting instruments: the Thermal Emission Spectrometer (TES) aboard Mars Global Surveyor, the Thermal Emission Imaging System (THEMIS) aboard Mars Odyssey, and the Mars Climate Sounder (MCS) aboard Mars Reconnaissance Orbiter (MRO). The procedure we have adopted consists of gridding the available retrievals of column dust optical depth (CDOD) from TES and THEMIS nadir observations, as well as the estimates of this quantity from MCS limb observations. Our gridding method calculates averages and uncertainties on a regularly spaced, but possibly incomplete, spatio-temporal grid, using an iterative procedure weighted in space, time, and retrieval uncertainty. In order to evaluate strengths and weaknesses of the resulting gridded maps, we validat...

Montabone, L; Millour, E; Wilson, R J; Lewis, S R; Cantor, B A; Kass, D; Kleinboehl, A; Lemmon, M; Smith, M D; Wolff, M J

2014-01-01T23:59:59.000Z

27

Magnetic Flares and the Observed Optical Depth in Seyfert Galaxies  

E-Print Network [OSTI]

We here consider the pressure equilibrium during an intense magnetic flare above the surface of a cold accretion disk. Under the assumption that the heating source for the plasma trapped within the flaring region is an influx of energy transported inwards with a group velocity close to $c$, e.g., by magnetohydrodynamic waves, this pressure equilibrium can constrain the Thomson optical depth $\\tau_T$ to be of order unity. We suggest that this may be the reason why $\\tau_T\\sim 1$ in Seyfert Galaxies. We also consider whether current data can distinguish between the spectrum produced by a single X-ray emitting region with $\\tau_T\\sim 1$ and that formed by many different flares spanning a range of $\\tau_T$. We find that the current observations do not yet have the required energy resolution to permit such a differentiation. Thus, it is possible that the entire X-ray/$\\gamma$-ray spectrum of Seyfert Galaxies is produced by many independent magnetic flares with an optical depth $0.5<\\tau_T<2$.

Sergei Nayakshin; Fulvio Melia

1997-05-30T23:59:59.000Z

28

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

E-Print Network [OSTI]

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...

Yi, Bingqi

2013-07-09T23:59:59.000Z

29

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

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

ProductsMicroPulse LIDAR Cloud Optical Depth ProductsMicroPulse LIDAR Cloud Optical Depth (MPLCOD) Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : MicroPulse LIDAR Cloud Optical Depth (MPLCOD) 1999.05.01 - 2004.05.14 Site(s) SGP General Description The MPLCOD VAP retrieves the column cloud visible optical depth using LIDAR derived backscatter from the MPLNOR (Micro Pulse Lidar Normalized Backscatter) and radiosonde thermodynamic profiles. The optical depth retrieval is derived following Comstock et al. (2001), which retrieves visible optical depth and layer average backscatter-to-extinction ratio (k) at the lidar wavelength for each backscatter profile. Data Information Data Directory Contacts Principal Investigator Jennifer Comstock (509) 372-424

30

Calibrations of filter radiometers for determination of atmospheric optical depth  

Science Journals Connector (OSTI)

Atmospheric optical depths are determined by relating ground-based measurements of direct solar radiation to the extraterrestrial value, I0, that a filter radiometer would read outside the atmosphere. Usually I0 is determined by the Langley extrapolation technique from a high-altitude site, where clear and highly stable atmospheric conditions may be found. Alternatively, I0 can be measured in situ from a stratospheric balloon experiment. We have employed both methods and found agreement to better than 1 %. Filter radiometers tend to change over time, especially when used operationally outdoors. Absolute calibrations in the laboratory are used to monitor the radiometric stability of filter radiometers at the Physikalisch-Meteorologisches Observatorium Davos (PMOD/WRC, Switzerland). A spectral calibration facility based on a calibrated trap detector from the Physikalisch-Technische Bundesanstalt (PTB, Germany) is used to relate the filter radiometer to an accurate and long-term traceable standard. An FEL-lamp-based standard, previously used for several years, was compared with the new trap standard via a filter radiometer at four wavelengths between 368 nm and 862 nm and revealed a systematic difference of the order of 5 %. The link between radiometric and I0 calibration is the value of the extraterrestrial solar spectrum at the filter radiometer wavelengths which can be determined from these two calibrations and compared with published values.

Ch Wehrli

2000-01-01T23:59:59.000Z

31

A Comparison of Cirrus Cloud Visible Optical Depth Derived from Lidar  

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

Comparison of Cirrus Cloud Visible Optical Depth Derived from Lidar Comparison of Cirrus Cloud Visible Optical Depth Derived from Lidar Lo, Chaomei Pacific Northwest National Laboratory Comstock, Jennifer Pacific Northwest National Laboratory Flynn, Connor Pacific Northwest National Laboratory Category: Cloud Properties Optically thin clouds (e.g. optical depth < 3) can have a significant impact on radiative heating in the atmosphere, particularly in the cold upper troposphere. Currently, there is no value-added product (VAP) in the Atmospheric Radiation Measurement (ARM) program archive that produces thin cloud optical depth, particularly at the Tropical Western Pacific and North Slope of Alaska sites. A VAP is under development to obtain the cirrus cloud visible optical depth from the MPLNOR (Micro Pulse Lidar Normalized

32

ARM - Publications: Science Team Meeting Documents: A decade long aerosol  

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

A decade long aerosol and cloud statistics and aerosol indirect effect at A decade long aerosol and cloud statistics and aerosol indirect effect at the ARM SGP site Min, Qilong State University of New York at Albany Duan, Minzheng State University of New York at Albany Harrison, Lee State University of New York Joseph, Everette Howard University Twelve-year data of MFRSR and MWR have been used to derive aerosol and cloud optical properties at the ARM SGP. Diurnal, monthly, seasonal and interannual variability of aerosol (optical depth and Angstrom coefficient) and cloud (optical depth and effective radius) have been analyzed. We specially focused on aerosol-cloud interactions. We found a signature of indirect aerosol effect for summer data: increased aerosol index has a statistically-significant anti-correlation with mean effective radius. No

33

Characteristics of aerosol optical properties in pollution and Asian dust episodes  

E-Print Network [OSTI]

Characteristics of aerosol optical properties in pollution and Asian dust episodes over Beijing, China Chenbo Xie,1,2 Tomoki Nishizawa,2, * Nobuo Sugimoto,2 Ichiro Matsui,2 and Zifa Wang3 1 Atmospheric for Atmospheric Optics, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei, Anhui

34

Direct Aerosol Forcing Uncertainty  

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

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.

Mccomiskey, Allison

35

Remote Sensing of Cirrus Cloud Particle Size and Optical Depth Using Polarimetric Sensor Measurements  

Science Journals Connector (OSTI)

This paper presents a conceptual approach toward the remote sensing of cirrus cloud particle size and optical depth using the degree of polarization and polarized reflectance associated with the first three Stokes parameters, I, Q, and U, for the ...

S. C. Ou; K. N. Liou; Y. Takano; R. L. Slonaker

2005-12-01T23:59:59.000Z

36

E-Print Network 3.0 - aerosol source-receptor relationships Sample...  

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

depth Summary: -continental transport Source-receptor relationships Aerosols Air quality Optical depth a b s t r a c t Our objectives... are to evaluate inter-continental...

37

Design of a Shadowband Spectral Radiometer for the Retrieval of Thin Cloud Optical Depth, Liquid Water Path, and the Effective Radius  

SciTech Connect (OSTI)

The design and operation of a Thin-Cloud Rotating Shadowband Radiometer (TCRSR) described here was used to measure the radiative intensity of the solar aureole and enable the simultaneous retrieval of cloud optical depth, drop effective radius, and liquid water path. The instrument consists of photodiode sensors positioned beneath two narrow metal bands that occult the sun by moving alternately from horizon to horizon. Measurements from the narrowband 415-nm channel were used to demonstrate a retrieval of the cloud properties of interest. With the proven operation of the relatively inexpensive TCRSR instrument, its usefulness for retrieving aerosol properties under cloud-free skies and for ship-based observations is discussed.

Bartholomew M. J.; Reynolds, R. M.; Vogelmann, A. M.; Min, Q.; Edwards, R.; Smith, S.

2011-11-01T23:59:59.000Z

38

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

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

Comparison of Cloud Top Height and Optical Depth Histograms from ISCCP, Comparison of Cloud Top Height and Optical Depth Histograms from ISCCP, MISR, and MODIS Marchand, Roger Pacific Northwest National Laboratory Ackerman, Thomas Pacific Northwest National Laboratory Category: Cloud Properties Joint histograms of Cloud Top Height (CTH) and Optical Depth (OD) derived by the International Satellite Cloud Climatology Project (ISCCP) are being widely used by the climate modeling community in evaluating global climate models. Similar joint histograms of CTH-OD are now being produced by the NASA Multi-angle Imaging Spectro-Radiometer (MISR) and Moderate Resolution Imaging Spectroradiometer (MODIS) instruments. There are notable differences in the histograms being produced by these three projects. In this poster we analyze some of the differences and discuss how the

39

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

E-Print Network [OSTI]

AND GASES EMITTED BY THE LABORATORY COMBUSTION OF WILDLAND FUELS Biomass burning is a major source of trace BY THE LABORATORY COMBUSTION OF WILDLAND FUELS Submitted by Gavin R. McMeeking Department of Atmospheric Science PROPERTIES OF AEROSOL AND GASES EMITTED BY THE LABORATORY COMBUSTION OF WILDLAND FUELS BE ACCEPTED

Pierce, Jeffrey

40

Constraints on primordial magnetic fields from the optical depth of the cosmic microwave background  

E-Print Network [OSTI]

Damping of magnetic fields via ambipolar diffusion and decay of magnetohydrodynamical (MHD) turbulence in the post decoupling era heats the intergalactic medium (IGM). Collisional ionization weakly ionizes the IGM, producing an optical depth to scattering of the cosmic microwave background (CMB). The optical depth generated at $z\\gg 10$ does not affect the "reionization bump" of the CMB polarization power spectrum at low multipoles, but affects the temperature and polarization power spectra at high multipoles. Using the Planck 2013 temperature and lensing data together with the WMAP 9-year polarization data, we constrain the present-day field strength, $B_0$, smoothed over the damping length at the decoupling epoch as a function of the spectral index, $n_B$. We find the 95% upper bounds of $B_0<0.56$, 0.31, and 0.14 nG for $n_B=-2.9$, $-2.5$, and $-1.5$, respectively. For these spectral indices, the optical depth is dominated by dissipation of the decaying MHD turbulence that occurs shortly after the decou...

Kunze, Kerstin E

2015-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Simultaneous determination of aerosol optical thickness and exponent of Junge power law from satellite measurements of two near-infrared bands over the ocean  

Science Journals Connector (OSTI)

An iterative algorithm is presented in this study for simultaneous determination of both the aerosol optical thickness and the exponent of the Junge power law from the total...

Xu, Qingshan; Wei, Heli; Rao, Ruizhong; Hu, Huanling

2007-01-01T23:59:59.000Z

42

ARM - PI Product - Direct Aerosol Forcing Uncertainty  

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

ProductsDirect Aerosol Forcing Uncertainty ProductsDirect Aerosol Forcing Uncertainty Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Direct Aerosol Forcing Uncertainty Site(s) NSA SGP TWP General Description 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

43

Measurement and Modeling of Vertically Resolved Aerosol Optical Properties and Radiative Fluxes Over the ARM SGP Site During the May 2003 Aerosol IOP  

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

Measurement and Modeling Measurement and Modeling of Vertically Resolved Aerosol Optical Properties and Radiative Fluxes Over the ARM SGP Site During the May 2003 Aerosol IOP B. Schmid and J. Redemann Bay Area Environmental Research Institute National Aeronautics and Space Administration Ames Research Center Moffett Field, California W. P. Arnott Desert Research Institute Reno, Nevada A. Bucholtz and J. Reid Naval Research Laboratory Monterey, California P. Colarco Earth System Science Interdisciplinary Center University of Maryland College Park, Maryland D. Covert and R. Elleman University of Washington Seattle, Washington J. Eilers, P. Pilewskie, and A. Strawa National Aeronautics and Space Administration Ames, Research Center Moffett Field, California R. A. Ferrare

44

Investigations of the Absorption Properties of Near-Ground Aerosol by the Methods of Optical-Acoustic Spectrometry and Diff...  

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

Investigations of the Absorption Properties of Investigations of the Absorption Properties of Near-Ground Aerosol by the Methods of Optical-Acoustic Spectrometry and Diffuse Extinction V. S. Kozlov, M. V. Panchenko, A. B. Tikhomirov, and B. A. Tikhomirov Institute of Atmospheric Optics Tomsk, Russia Introduction Aerosol absorption is an important factor in the formation of non-selective radiation extinction in the visible wavelength range, and plays a great role in solving many radiative and climatic problems. The principal absorbing substance in atmospheric aerosol is soot (crystal carbon), which strongly affects the atmospheric transparency, albedo of clouds, and snow cover. The non-selective absorption by finely dispersed soot aerosol is considered to be one of the most plausible reasons for the appearance of

45

Aerosol Optical Depth Prediction from Satellite Observations by Multiple Instance Regression  

E-Print Network [OSTI]

airborne particles that both reflect and absorb incoming solar radiation and whose effect on the Earth's radiation budget is one of the biggest challenges of current climate research. To help address requirement for the success of the ensuing scientific studies. Among the most challenging climate research

Vucetic, Slobodan

46

The use of satellite-measured aerosol optical depth to constrain biomass burning emissions source  

E-Print Network [OSTI]

Spectroradiometer (MODIS) products, effective fuel load, and species emission factors as alternative inputs and daily versions, Fire Radiative Power (FRP)-based Quick Fire Emission Data set QFED, and 11 calculated, Earth Science Directorate, NASA Goddard Space Flight Center, Code 613, Greenbelt, MD 20771, USA

Chin, Mian

47

Retrieval of Non-Spherical Dust Aerosol Properties from Satellite Observations  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 4.2 Comparison between the MODIS RGB image (left panel) and aerosol optical depth derived in the MODIS Deep Blue product (right panel) over the Sahara Desert on April 1, 2010. . . . . . . . . . . . . . . . . 85 xii 4.3 Comparison between.... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84 4.2 Comparison between the MODIS RGB image (left panel) and aerosol optical depth derived in the MODIS Deep Blue product (right panel) over the Sahara Desert on April 1, 2010. . . . . . . . . . . . . . . . . 85 xii 4.3 Comparison between...

Huang, Xin

2013-08-01T23:59:59.000Z

48

An Observed Signature of Aerosol Effect on Cloud Droplet Radii from a  

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

An Observed Signature of Aerosol Effect on Cloud Droplet Radii from a An Observed Signature of Aerosol Effect on Cloud Droplet Radii from a Decade of Observations at a Mid-Continental Site Min, Qilong State University of New York at Albany Duan, Minzheng State University of New York at Albany Harrison, Lee State University of New York Joseph, Everette Howard University Category: Aerosols Continuing observations of aerosol and cloud optical property have been made using MFRSR and MWR at the ARM SGP site since 1993. Diurnal, monthly, seasonal and interannual variability of aerosol (optical depth and Angstrom coefficient) and cloud (optical depth and effective radius) have been analyzed. We have correlated an "aerosol index" computed from clear-sky observations of MFRSR with cloud droplet mean effective radius to study the

49

AEROgui: A graphical user interface for the optical properties of aerosols  

Science Journals Connector (OSTI)

Atmospheric aerosols have an uncertain effect on climate, and serious impact on human health. The uncertainty in the aerosols role on climate has several sources. First, aerosols present a great spatial and temporal variability. The spatial variability ...

R. Pedrs; J.L. Gmez-Amo; C.R. Marcos; M.P. Utrillas; S. Ganda; F. Tena; J.A. Martinez Lozano

50

Aerosol optical and hygroscopic properties during TexAQS-GoMACCS 2006 and their impact on aerosol  

E-Print Network [OSTI]

by diesel-fueled mobile sources and from the numerous coal- fired industries and power generation stations August thru 11 September 2006) with a number of gas and aerosol instru- ments deployed to measure air and power plants, with emissions rich in reactive volatile organic compounds (VOCs) and NOX [Ryerson et al

51

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

E-Print Network [OSTI]

properties of a biomass burning aerosol generated from fires on the Yucatan Peninsula. Measured aerosol size distributions and size-resolved hygroscopicity and volatility were used to infer critical supersaturation distributions of the distinct particle types...

Lee, Yong Seob

2006-08-16T23:59:59.000Z

52

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

E-Print Network [OSTI]

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.

Kumiko Kotera; Martin Lemoine

2008-04-30T23:59:59.000Z

53

March 14, 2011 NIST Aerosol Metrology Workshop Optical Properties: The Global  

E-Print Network [OSTI]

are difficult without involving satellite measurements Correspondence with satellite measurements require. Improved regional forecasts of both weather and air quality #12;GAW Aerosol Lidar Observation Network

54

Aerosol optical properties and their radiative effects in northern Zhanqing Li,1,2,3  

E-Print Network [OSTI]

and may also affect the hydrologic cycle. By scattering and absorbing solar radiative energy, aerosols regions. The East Asian Study of Tropospheric Aerosols: An International Regional Experiment (EAST-AIRE on climate over China. This study presents some preliminary results using continuous high-quality

Dickerson, Russell R.

55

Rapid optical method for logging dust concentration versus depth in glacial ice  

E-Print Network [OSTI]

to a cable that can lower the device down a 3-in. 7.5-cm borehole filled with butyl acetate. LED photons to the attenuation by particles.6 The AMANDA collaboration recently completed a large observatory, buried in deep a hot-water drilling tech- nique, they melted cylindrical holes down to depths of 2000 m in which were

Price, P. Buford

56

The Two-Column Aerosol Project (TCAP) Science Plan  

SciTech Connect (OSTI)

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.

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

2011-07-27T23:59:59.000Z

57

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

E-Print Network [OSTI]

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 ...

Cappa, Christopher D.

58

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

E-Print Network [OSTI]

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.

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

2010-01-01T23:59:59.000Z

59

ARM - Field Campaign - 2006 MAX-Mex-Megacity Aerosol eXperiment - Mexico  

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

6 MAX-Mex-Megacity Aerosol eXperiment - Mexico City 6 MAX-Mex-Megacity Aerosol eXperiment - Mexico City Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : 2006 MAX-Mex-Megacity Aerosol eXperiment - Mexico City 2006.03.03 - 2006.03.28 Lead Scientist : Jeffrey Gaffney For data sets, see below. Description A 4-week field campaign was conducted in and downwind of Mexico City during March 2006. The Megacity Aerosol eXperiment - MEXico City (MAX-MEX) characterized aerosol formation and changes in aerosol composition, size distribution, light scattering coefficient, absorption coefficient, optical depth, soot-specific absorption, and radiative fluxes at selected vertical and horizontal locations in the outflow from a well-characterized urban core. Detailed analyses were made of the meteorological conditions during

60

E-Print Network 3.0 - aerosol chemical vapor Sample Search Results  

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

chemical and microphysical properties influence aerosol optical properties and radiative effects... distribution of aerosol extensive and intensive properties will aid ......

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

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

E-Print Network [OSTI]

.F. Hanlon,1 C.M. Hoffman,2 M.H. Holzscheiter,2 G.A. Hughes,6 P. H¨untemeyer,1 C.C.H. Jui,1 M.A. Kirn,3 BZvi,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 K. Reil,1 M.D. Roberts,8 S.R. Schnetzer,6 M. Seman,4 G. Sinnis,2 J.D. Smith,1 P. Sokolsky,1 C. Song

62

Correlations Between Optical, Chemical and Physical Properties...  

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

Biomass Burn Aerosols. Correlations Between Optical, Chemical and Physical Properties of Biomass Burn Aerosols. Abstract: Single scattering albedo (?) and Angstrom...

63

The Influence of Fog and Airmass History on Aerosol Optical, Physical and Chemical Properties at Pt. Reyes National Seashore  

SciTech Connect (OSTI)

This paper presents an analysis of the aerosol chemical composition, optical properties and size distributions for a range of conditions encountered during a field measurement campaign conducted between July 7-29, 2005 at Point Reyes National Seashore, north of San Francisco, CA. Observations are partitioned into one-hour periods when conditions were clear or foggy to identify evidence of cloud processing of aerosols. During the first half of the campaign (July 7-18), conditions at the site were largely maritime. However flow during the second half of the campaigns (July 18-29) was influenced by a thermal trough that added a cyclonic twist to the incoming marine air, bringing it from the south with a more extensive over-land trajectory. Neither flow regime was associated with air coming from the San Francisco Bay area to the south. Measurements by an Aerodyne aerosol mass spectrometer (AMS) of the equivalent molar ratio of ammonium to the sum of sulfate, nitrate and chloride made before the onset of the thermal trough on July 18th were associated with acidic or near-neutral particles. Measurements made after July 18th appear to have excess ammonium. The AMS measurements of mass loading were an order of magnitude less than those reported by a nearby IMPROVE station. However, the AMS measures only non-refractory particles between 0.1 m and 1 m, which would not include sea salt. In contrast, the IMPROVE station employs filter-based techniques to measure mass for all particles < 2.5 m. Assuming chlorine is associated with large sea salt particles at Pt. Reyes and removing this value from the IMPROVE data resulted in good agreement in the total mass fraction between these two techniques,, indicating the importance of sea salt mass in particles greater than 1 m. Model calculations of the equilibrium gas-phase mixing ratio of NH3 suggest very high values which we attribute to agricultural practices within the park. Reported as an incidental finding is evidence for the cloud droplet activation of large particles (diameter >0.2 mm) with a corresponding reduction in the single scattering albedo of the non-activated particles, followed by a return in the particle size spectrum to the pre-fog conditions immediately afterwards.

Berkowitz, Carl M.; Berg, Larry K.; Yu, Xiao-Ying; Alexander, M. L.; Laskin, Alexander; Zaveri, Rahul A.; Jobson, Bertram Thomas; Andrews, Elisabeth; Ogren, John A.

2011-04-05T23:59:59.000Z

64

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

SciTech Connect (OSTI)

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.

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

2014-05-13T23:59:59.000Z

65

E-Print Network 3.0 - aerosol optical properties Sample Search...  

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

the U.S. Department of Energy under Contract No. DE-AC02-98CH10886. Summary: ) of the solar radiation back to space, and an indirect one by determining cloud optical properties...

66

Aerosol Observing System (AOS) Handbook  

SciTech Connect (OSTI)

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 earths 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.

Jefferson, A

2011-01-17T23:59:59.000Z

67

Photoacoustic optical properties at UV, VIS, and near IR wavelengths for laboratory generated and winter time ambient urban aerosols  

SciTech Connect (OSTI)

We present the laboratory and ambient photoacoustic (PA) measurement of aerosol light absorption coefficients at ultraviolet wavelength (i.e., 355 nm) and compare with measurements at 405, 532, 870, and 1047 nm. Simultaneous measurements of aerosol light scattering coefficients were achieved by the integrating reciprocal nephelometer within the PA's acoustic resonator. Absorption and scattering measurements were carried out for various laboratory generated aerosols, including salt, incense, and kerosene soot to evaluate the instrument calibration and gain insight on the spectral dependence of aerosol light absorption and scattering. Ambient measurements were obtained in Reno, Nevada, between 18 December 2009 and 18 January 2010. The measurement period included days with and without strong ground level temperature inversions, corresponding to highly polluted (freshly emitted aerosols) and relatively clean (aged aerosols) conditions. Particulate matter (PM) concentrations were measured and analyzed with other tracers of traffic emissions. The temperature inversion episodes caused very high concentration of PM{sub 2.5} and PM{sub 10} (particulate matter with aerodynamic diameters less than 2.5 {mu}m and 10 {mu}m, respectively) and gaseous pollutants: carbon monoxide (CO), nitric oxide (NO), and nitrogen dioxide (NO{sub 2}). The diurnal change of absorption and scattering coefficients during the polluted (inversion) days increased approximately by a factor of two for all wavelengths compared to the clean days. The spectral variation in aerosol absorption coefficients indicated a significant amount of absorbing aerosol from traffic emissions and residential wood burning. The analysis of single scattering albedo (SSA), Angstrom exponent of absorption (AEA), and Angstrom exponent of scattering (AES) for clean and polluted days provides evidences that the aerosol aging and coating process is suppressed by strong temperature inversion under cloudy conditions. In general, measured UV absorption coefficients were found to be much larger for biomass burning aerosol than for typical ambient aerosols.

Gyawali, Madhu S.; Arnott, W. Patrick; Zaveri, Rahul A.; Song, Chen; Moosmuller, H.; Liu, Li; Mishchenko, M.; Chen, L-W A.; Green, M.; Watson, J. G.; Chow, J. C.

2012-03-08T23:59:59.000Z

68

ARM - PI Product - Aerosol Retrievals from ARM SGP MFRSR Data  

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

ProductsAerosol Retrievals from ARM SGP MFRSR Data ProductsAerosol Retrievals from ARM SGP MFRSR Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Aerosol Retrievals from ARM SGP MFRSR Data 2000.01.01 - 2000.12.31 Site(s) SGP General Description 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

69

aerosols | EMSL  

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

aerosols aerosols Leads No leads are available at this time. Magnesium behavior and structural defects in Mg+ ion implanted silicon carbide. Abstract: As a candidate material for...

70

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

SciTech Connect (OSTI)

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)

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

2011-10-31T23:59:59.000Z

71

Temporal Variability of Aerosol Properties during TCAP: Impact on Radiative Forcing  

SciTech Connect (OSTI)

Ground-based remote sensing and in situ observations of aerosol microphysical and optical properties have been collected during summertime (June-August, 2012) as part of the Two-Column Aerosol Project (TCAP; http://campaign.arm.gov/tcap/), which was supported by the U.S. Department of Energys (DOEs) Atmospheric Radiation Measurement (ARM) Program (http://www.arm.gov/). The overall goal of the TCAP field campaign is to study the evolution of optical and microphysical properties of atmospheric aerosol transported from North America to the Atlantic and their impact on the radiation energy budget. During TCAP, the ground-based ARM Mobile Facility (AMF) was deployed on Cape Cod, an arm-shaped peninsula situated on the easternmost portion of Massachusetts (along the east coast of the United States) and that is generally downwind of large metropolitan areas. The AMF site was equipped with numerous instruments for sampling aerosol, cloud and radiative properties, including a Multi-Filter Rotating Shadowband Radiometer (MFRSR), a Scanning Mobility Particle Sizer (SMPS), an Aerodynamic Particle Sizer (APS), and a three-wavelength nephelometer. In this study we present an analysis of diurnal and day-to-day variability of the column and near-surface aerosol properties obtained from remote sensing (MFRSR data) and ground-based in situ measurements (SMPS, APS, and nephelometer data). In particular, we show that the observed diurnal variability of the MFRSR aerosol optical depth is strong and comparable with that obtained previously from the AERONET climatology in Mexico City, which has a larger aerosol loading. Moreover, we illustrate how the variability of aerosol properties impacts the direct aerosol radiative forcing at different time scales.

Kassianov, Evgueni I.; Barnard, James C.; Pekour, Mikhail S.; Berg, Larry K.; Fast, Jerome D.; Michalsky, Joseph J.; Lantz, K.; Hodges, G. B.

2013-11-01T23:59:59.000Z

72

Direct and semidirect aerosol effects of Southern African biomass burning aerosol  

SciTech Connect (OSTI)

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.

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

2011-06-21T23:59:59.000Z

73

Polarization-dependent all-optical modulator with ultra-high modulation depth based on a stereo graphene-microfiber structure  

E-Print Network [OSTI]

We report an in-line polarization-dependent all-optical fiber modulator based on a stereo graphene-microfiber structure (GMF) by utilizing the lab-on-rod technique. Owing to the unique spring-like geometry, an ultra-long GMF interaction length can be achieved, and an ultra-high modulation depth (MD) of ~7.5 dB and a high modulation efficiency (ME) of ~0.2 dB/mW were demonstrated for one polarization state. The MD and ME are more than one order larger than those of other graphene-waveguide hybrid all-optical modulators. By further optimizing the transferring and cleaning process, the modulator can quickly switch between transparent and opaque states for both the two polarization states with a maximized MD of tens of decibels. This modulator is compatible with current fiber-optic communication systems and may be applied in the near future to meet the impending need for ultrafast optical signal processing.

Xu, Fei; Zheng, Bi-cai; Shao, Guang-hao; Ge, Shi-jun; Lu, Yan-qing

2015-01-01T23:59:59.000Z

74

Ganges Valley Aerosol Experiment: Science and Operations Plan  

SciTech Connect (OSTI)

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 912 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 612 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 abundancein 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.

Kotamarthi, VR

2010-06-21T23:59:59.000Z

75

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

SciTech Connect (OSTI)

In the recent chemistry version (v3.3) of the Weather Research and Forecasting (WRF-Chem) model, we have coupled the Morrison double-moment microphysics scheme with interactive aerosols so that full two-way aerosol-cloud interactions are included in simulations. We have used this new WRF-Chem functionality in a study focused on assessing predictions of aerosols, marine stratocumulus clouds, and their interactions over the Southeast Pacific using measurements from the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) and satellite retrievals. This study also serves as a detailed analysis of our WRF-Chem simulations contributed to the VOCALS model Assessment (VOCA) project. The WRF-Chem 31-day (October 15-November 16, 2008) simulation with aerosol-cloud interactions (AERO hereafter) is also compared to a simulation (MET hereafter) with fixed cloud droplet number concentrations assumed by the default in Morrison microphysics scheme with no interactive aerosols. The well-predicted aerosol properties such as number, mass composition, and optical depth lead to significant improvements in many features of the predicted stratocumulus clouds: cloud optical properties and microphysical properties such as cloud top effective radius, cloud water path, and cloud optical thickness, and cloud macrostructure such as cloud depth and cloud base height. These improvements in addition to the aerosol direct and semi-direct effects, in turn, feed back to the prediction of boundary-layer characteristics and energy budgets. Particularly, inclusion of interactive aerosols in AERO strengths temperature and humidity gradients within capping inversion layer and lowers the MBL depth by 150 m from that of the MET simulation. Mean top-of-the-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 over the remote ocean) and aerosol quantities (e.g., overestimations of supermicron sea salt mass) might affect simulated stratocumulus and energy fluxes over the SEP, and require further investigations. Although not perfect, the overall performance of the regional model in simulating mesoscale aerosol-cloud interactions is encouraging and suggests that the inclusion of spatially varying aerosol characteristics is important when simulating marine stratocumulus over the southeastern Pacific.

Yang, Qing; Gustafson, William I.; Fast, Jerome D.; Wang, Hailong; Easter, Richard C.; Morrison, H.; Lee, Y.- N.; Chapman, Elaine G.; Spak, S. N.; Mena-Carrasco, M. A.

2011-12-02T23:59:59.000Z

76

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

SciTech Connect (OSTI)

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.

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

2011-12-02T23:59:59.000Z

77

Multi-year Satellite and Surface Observations of AOD in support of Two-Column Aerosol Project (TCAP) Field Campaign  

SciTech Connect (OSTI)

We use combined multi-year measurements from the surface and space for assessing the spatial and temporal distribution of aerosol properties within a large (~400x400 km) region centered on Cape Cod, Massachusetts, along the East Coast of the United States. The ground-based Aerosol Robotic Network (AERONET) measurements at Marthas Vineyard Coastal Observatory (MVCO) site and Moderate Resolution Imaging Spectrometer (MODIS) sensors on board the Terra and Aqua satellites provide horizontal and temporal variations of aerosol optical depth, while the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) offers the altitudes of aerosol-layers. The combined ground-based and satellite measurements indicated several interesting features among which were the large differences in the aerosol properties observed in July and February. We applied the climatology of aerosol properties for designing the Two-Column Aerosol Project (TCAP), which is supported by the U.S. Department of Energys (DOEs) Atmospheric Radiation Measurement (ARM) Program. The TCAP field campaign involves 12-month deployment (started July 1, 2012) of the ground-based ARM Mobile Facility (AMF) and Mobile Aerosol Observing System (MAOS) on Cape Cod and complimentary aerosol observations from two research aircraft: the DOE Gulfstream-1 (G-1) and the National Aeronautics and Space Administration (NASA) B200 King Air. Using results from the coordinated G-1 and B200 flights during the recent (July, 2012) Intensive Observation Period, we demonstrated that the G-1 in situ measurements and B200 active remote sensing can provide complementary information on the temporal and spatial changes of the aerosol properties off the coast of North America.

Kassianov, Evgueni I.; Chand, Duli; Berg, Larry K.; Fast, Jerome D.; Tomlinson, Jason M.; Ferrare, R.; Hostetler, Chris A.; Hair, John

2012-11-01T23:59:59.000Z

78

ARM - Field Campaign - Fall 1997 Aerosol IOP  

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

Aerosol IOP Aerosol IOP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Fall 1997 Aerosol IOP 1997.09.15 - 1997.10.05 Lead Scientist : Stephen Schwartz For data sets, see below. Summary The Aerosol IOP was highlighted by the Gulfstream-1 aircraft flying clear-sky aerosol missions over the Central Facility to study the effect of aerosol loading on clear sky radiation fields, with weather particularly favorable for these flights during the first and third weeks of the IOP. A secondary but important goal of this IOP was to fly cloudy-sky missions over the Central Facility to study the effect of aerosol loading on cloud microphysics, and the effect of the microphysics on cloud optical properties. The Gulfstream obtained aerosol data in support of some of the

79

CARES: Carbonaceous Aerosol and Radiative Effects Study Science Plan  

SciTech Connect (OSTI)

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.

Zaveri, RA; Shaw, WJ; Cziczo, DJ

2010-05-27T23:59:59.000Z

80

Influence of local waste burning on atmospheric aerosol properties in urban environment  

Science Journals Connector (OSTI)

Aerosols affect the radiative energy budget on both the regional and global scales. The wavelength-dependent aerosol optical depth (AOD) is a fundamental determinant of the amount by which extra-terrestrial incoming sunlight and outgoing terrestrial radiation are being attenuated in the atmosphere. The present study addresses the influence of local waste burning on aerosol characteristics, black carbon (BC) aerosol mass concentration and spectral solar irradiance using ground-based measurements over the tropical urban environment of Hyderabad, India. AOD has been observed to be maximum during burning days compared to normal days. Aerosol size spectra suggest bimodal distributions during pre-and post-burning periods and trimodal distributions during burning periods. Angstrom wavelength exponent estimated from spectral variation of AOD suggested dominance of accumulation mode particle loading during burning days compared to normal days. Diurnal variation of BC on normal days showed a broad nocturnal peak during ?20:00 to ?24:00h with a maximum value of BC aerosol concentration of ?14,000ngm?3 whereas on local waste burning days enormous increases in BC concentrations have been observed with a peak at ?60,000ngm?3. Relative attenuation of global solar irradiance during burning days has been found to be of the order of 30% in the visible and 28% in the near-infrared regions. The results are discussed in detail in this paper.

K. Madhavi Latha; K.V.S. Badarinath

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Detection of internally mixed Asian dust with air pollution aerosols using a polarization optical particle counter and a polarization-sensitive two-wavelength lidar  

Science Journals Connector (OSTI)

Abstract East Asia is a unique region where mineral dust (Asian dust) sources are located near urban and industrial areas. Asian dust is often mixed with air pollution aerosols during transportation. It is important to understand the mixing states of Asian dust and other aerosols, because the effects on the environment and human health differ depending on the mixing state. We studied the mixing states of Asian dust using a polarization particle counter (POPC) that measures the forward scattering and the two polarization components of backscattering for single particles and a polarization-sensitive (532nm) two-wavelength (1064nm and 532nm) lidar. We conducted the simultaneous observations using the POPC and the lidar in Seoul from March to December 2013 and captured the characteristics of pure Asian dust and internally mixed polluted Asian dust. POPC measurements indicated that the density of large particles was lower in polluted Asian dust that transported slowly over the polluted areas than in pure Asian dust that transported quickly from the dust source region. Moreover, the backscattering depolarization ratio was smaller for all particle sizes in polluted dust. The optical characteristics measured using the lidar were consistent with the POPC measurements. The backscattering color ratio of polluted dust was comparable to that of pure dust, but the depolarization ratio was lower for polluted dust. In addition, coarse non-spherical particles (Asian dust) almost always existed in the background, and the depolarization ratio had seasonal variation with a lower depolarization ratio in the summer. These results suggest background Asian dust particles are internally mixed in the summer.

Nobuo Sugimoto; Tomoaki Nishizawa; Atsushi Shimizu; Ichiro Matsui; Hiroshi Kobayashi

2015-01-01T23:59:59.000Z

82

E-Print Network 3.0 - aerosol generation characterization Sample...  

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

Summary: , Brookhaven National Laboratory: "Characterization of Aerosol Organic Matter: Detection, Formation and Optical... : "Atmospheric Formation, Transformation, and...

83

Atmospheric Radiation Measurement (ARM) Data from Cape Cod, Massachusetts for the Two-Column Aerosol Project (TCAP)  

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

The Two-Column Aerosol Project (TCAP) was designed to 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 ARM Mobile Facility and the Mobile Aerosol Observing System were deployed 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 were supplemented by two aircraft intensive observation periods, one in the summer and a second in the winter.

84

Assessment of Aerosol Radiative Impact over Oceanic Regions Adjacent to Indian Subcontinent using Multi-Satellite Analysis  

SciTech Connect (OSTI)

Using data from Ozone Monitoring Instrument (OMI) and Moderate Resolution Imaging Spectroradiometer (MODIS) instruments, we have retrieved regional distribution of aerosol column single scattering albedo (parameter indicative of the relative dominance of aerosol absorption and scattering effects), a most important, but least understood aerosol property in assessing its climate impact. Consequently we provide improved assessment of short wave aerosol radiative forcing (ARF) (on both regional and seasonal scales) estimates over this region. Large gradients in north-south ARF were observed as a consequence of gradients in single scattering albedo as well as aerosol optical depth. The highest ARF (-37 W m-2 at the surface) was observed over the northern Arabian Sea during June to August period (JJA). In general, ARF was higher over northern Bay of Bengal (NBoB) during winter and pre-monsoon period, whereas the ARF was higher over northern Arabian Sea (NAS) during the monsoon and post- monsoon period. The largest forcing observed over NAS during JJA is the consequence of large amounts of desert dust transported from the west Asian dust sources. High as well as seasonally invariant aerosol single scattering albedos (~0.98) were observed over the southern Indian Ocean region far from continents. The ARF estimates based on direct measurements made at a remote island location, Minicoy (8.3N, 73E) in the southern Arabian Sea are in good agreement with the estimates made following multisatellite analysis.

Satheesh, S. K.; Vinoj, V.; Krishnamoorthy, K.

2010-10-01T23:59:59.000Z

85

Evaluation of the carbon content of aerosols from the burn- ing of biomass in the Brazilian Amazon using thermal, op- tical and thermal-optical analysis methods  

E-Print Network [OSTI]

from Smoldering Biomass Combustion. Atmos. Chem. Phys. , 10,aerosols emitted during biomass combustion [Robinson et al.burning samples. Combustion of biomass produces EC a and

Soto-Garcia, Lydia L.

2012-01-01T23:59:59.000Z

86

Photometric Variations as Small Perturbations in Aerosol Content  

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

Photometric Variations as Photometric Variations as Small Perturbations in Aerosol Content I. Musat Department of Meteorology University of Maryland College Park, Maryland R. G. Ellingson Department of Meteorology Florida State University Tallahassee, Florida Abstract The quality of profile fitting of resolved stars depends ultimately upon the accuracy with which spectral differences of the sources are retrievable within the data, because the radiation color of well-separated known sources can serve as an indicator of the origin of the optical depth variations one observes during the night. The particularities of the whole sky imager (WSI) detector and optical system are such that the data suffer from lack of the spatial resolution required in a common astronomical observation.

87

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

SciTech Connect (OSTI)

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.

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

2009-04-10T23:59:59.000Z

88

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

SciTech Connect (OSTI)

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.

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.

2012-03-30T23:59:59.000Z

89

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

SciTech Connect (OSTI)

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 ARMs 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 ARMs operational data processing.

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

2014-04-10T23:59:59.000Z

90

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

SciTech Connect (OSTI)

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.

D. Jui-Yuan Chiu

2010-10-19T23:59:59.000Z

91

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

SciTech Connect (OSTI)

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.

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

2009-03-05T23:59:59.000Z

92

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

SciTech Connect (OSTI)

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.

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

2014-09-23T23:59:59.000Z

93

MRO/CRISM Retrieval of Surface Lambert Albedos for Multispectral Mapping of Mars with DISORT-based Rad. Transfer Modeling: Phase 1 - Using Historical Climatology for Temperatures, Aerosol Opacities, & Atmo. Pressures  

E-Print Network [OSTI]

We discuss the DISORT-based radiative transfer pipeline ('CRISM_LambertAlb') for atmospheric and thermal correction of MRO/CRISM data acquired in multispectral mapping mode (~200 m/pixel, 72 spectral channels). Currently, in this phase-one version of the system, we use aerosol optical depths, surface temperatures, and lower-atmospheric temperatures, all from climatology derived from Mars Global Surveyor Thermal Emission Spectrometer (MGS-TES) data, and surface altimetry derived from MGS Mars Orbiter Laser Altimeter (MOLA). The DISORT-based model takes as input the dust and ice aerosol optical depths (scaled to the CRISM wavelength range), the surface pressures (computed from MOLA altimetry, MGS-TES lower-atmospheric thermometry, and Viking-based pressure climatology), the surface temperatures, the reconstructed instrumental photometric angles, and the measured I/F spectrum, and then outputs a Lambertian albedo spectrum. The Lambertian albedo spectrum is valuable geologically since it allows the mineralogical ...

McGuire, P C; Smith, M D; Arvidson, R E; Murchie, S L; Clancy, R T; Roush, T L; Cull, S C; Lichtenberg, K A; Wiseman, S M; Green, R O; Martin, T Z; Milliken, R E; Cavender, P J; Humm, D C; Seelos, F P; Seelos, K D; Taylor, H W; Ehlmann, B L; Mustard, J F; Pelkey, S M; Titus, T N; Hash, C D; Malaret, E R

2009-01-01T23:59:59.000Z

94

E-Print Network 3.0 - assessing aerosol retention Sample Search...  

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

optical properties in the vicinity of biologically active... regions of the ocean. Detection of aerosol signal associated with the ocean ecosystem will provide Source:...

95

E-Print Network 3.0 - aerosol wastes Sample Search Results  

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

Schwartz Proc. Aerosols and Atmospheric Optics Radiation Balance... and Visual Air Quality, Snowbird, UT, Sept. 26-30, pp. 403-409, Air and Waste Management Association... ,...

96

E-Print Network 3.0 - aerosol properties in-canopy Sample Search...  

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

in-canopy Page: << < 1 2 3 4 5 > >> 1 Quantitative Assessments of Radiative and Optical Properties of Marine Biogenic Aerosol PI: N. Meskhidze (NCSU) Summary: Quantitative...

97

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

E-Print Network [OSTI]

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 ...

Ridley, David Andrew

98

BNL | Two-Column Aerosol Program (TCAP)  

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

Two-Column Aerosol Project (TCAP) Two-Column Aerosol Project (TCAP) There remain many key knowledge gaps despite advances in the scientific understanding of how aerosols and clouds evolve and affect climate. Many climatically important processes depend on particles that undergo continuous changes within a size range spanning a few nanometers to a few microns, and with compositions that consist of a variety of carbonaceous materials, soluble inorganic salts and acids and insoluble mineral dust. Primary particles, which are externally-mixed when emitted, are subject to coagulation and chemical changes associated with the condensation of semi-volatile gases to their surface resulting in a spectrum of compositions or mixing-states with a range of climate-affecting optical and hygroscopic properties. The numerical treatments of aerosol transformation

99

Aerosol Best Estimate Value-Added Product  

SciTech Connect (OSTI)

The objective of the Aerosol Best Estimate (AEROSOLBE) value-added product (VAP) is to provide vertical profiles of aerosol extinction, single scatter albedo, asymmetry parameter, and Angstroem exponents for the atmospheric column above the Central Facility at the ARM Southern Great Plains (SGP) site. We expect that AEROSOLBE will provide nearly continuous estimates of aerosol optical properties under a range of conditions (clear, broken clouds, overcast clouds, etc.). The primary requirement of this VAP was to provide an aerosol data set as continuous as possible in both time and height for the Broadband Heating Rate Profile (BBHRP) VAP in order to provide a structure for the comprehensive assessment of our ability to model atmospheric radiative transfer for all conditions. Even though BBHRP has been completed, AEROSOLBE results are very valuable for environmental, atmospheric, and climate research.

Flynn, C; Turner, D; Koontz, A; Chand, D; Sivaraman, C

2012-07-19T23:59:59.000Z

100

Effects of aerosol and horizontal inhomogeneity on the broadband albedo of marine stratus: Numerical simulations  

SciTech Connect (OSTI)

Recent estimates of the effect of increasing of anthropogenic sulfate aerosol on the radiative forcing of the atmosphere have indicated that its impact may be comparable in magnitude to the effect from increases in CO{sub 2}. Much of this impact is expected from the effects of the aerosol on cloud microphysics and the subsequent impact on cloud albedo. A solar broadband version of a 2D radiative transfer model was used to quantify the impact of enhanced aerosol concentrations and horizontal inhomogeneity on the solar broadband albedo of marine stratus. The results of the radiative transfer calculations indicated that in unbroken marine stratus clouds the net horizontal transport of photons over a domain of a few kilometers was nearly zero, and the domain-average broadband albedo computed in a 2D cross section was nearly identical to the domain average calculated from a series of independent pixel approximation (IPA) calculations of the same cross section. However, the horizontal inhomogeneity does affect the cloud albedo compared to plane-parallel approximation (PPA) computations due to the nonlinear relationship between albedo and optical depth. The reduction in cloud albedo could be related to the variability of the distribution of log (cloud optical depth). These results extend the finding of Cahalan et al. to broadband solar albedos in a more realistic cloud model and suggest that accurate computation of domain-averaged broadband albedos in unbroken (or nearly unbroken) marine stratus can be made using IPA calculations with 1D radiative transfer models. Computations of the mean albedo over portions of the 3D RAMS domain show the relative increase in cloud albedo due to a 67% increase in the boundary-layer average CCN concentration was between 6% and 9%. The effects of cloud inhomogeneity on the broadband albedo as measured from the PPA bias ranged from 3% to 5%. 25 refs., 8 figs., 4 tabs.

Duda, D.P.; Stephens, G.L.; Stevens, B.; Cotton, W.R. [Colorado State Univ., Fort Collins, CO (United States)] [Colorado State Univ., Fort Collins, CO (United States)

1996-12-15T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

ARM - Field Campaign - 2007 Cumulus Humilis Aerosol Process Study (CHAPS)  

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

7 Cumulus Humilis Aerosol Process Study (CHAPS) 7 Cumulus Humilis Aerosol Process Study (CHAPS) Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : 2007 Cumulus Humilis Aerosol Process Study (CHAPS) 2007.06.04 - 2007.06.25 Lead Scientist : Carl Berkowitz For data sets, see below. Description The primary goal of this campaign was to characterize and contrast freshly emitted aerosols above, within and below fields of cumulus humilis (or fair-weather cumulus, FWC) and to use these observations to address how below-cloud and above-cloud aerosol optical and cloud nucleating properties differ downwind of a mid-size city relative to similar aerosols in air less affected by emissions. The observations from this campaign can also be used to aid in the development and evaluation of parameterizations of the

102

Do Diurnal Aerosol Changes Affect Daily Average Radiative Forcing?  

SciTech Connect (OSTI)

Strong diurnal variability of aerosol has been observed frequently for many urban/industrial regions. How this variability may alter the direct aerosol radiative forcing (DARF), however, is largely unknown. To quantify changes in the time-averaged DARF, we perform an assessment of 29 days of high temporal resolution ground-based data collected during the Two-Column Aerosol Project (TCAP) on Cape Cod, which is downwind of metropolitan areas. We demonstrate that strong diurnal changes of aerosol loading (about 20% on average) have a negligible impact on the 24-h average DARF, when daily averaged optical properties are used to find this quantity. However, when there is a sparse temporal sampling of aerosol properties, which may preclude the calculation of daily averaged optical properties, large errors (up to 100%) in the computed DARF may occur. We describe a simple way of reducing these errors, which suggests the minimal temporal sampling needed to accurately find the forcing.

Kassianov, Evgueni I.; Barnard, James C.; Pekour, Mikhail S.; Berg, Larry K.; Michalsky, Joseph J.; Lantz, K.; Hodges, G. B.

2013-06-17T23:59:59.000Z

103

Improved solid aerosol generator  

DOE Patents [OSTI]

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.

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

1988-07-19T23:59:59.000Z

104

Factors influencing the microphysics and radiative properties of liquid-dominated Arctic clouds: insight from observations of aerosol and clouds during ISDAC  

SciTech Connect (OSTI)

Aircraft measurements during the Indirect and Semi-Direct Aerosol Campaign (ISDAC) in April 2008 are used to investigate aerosol indirect effects in Arctic clouds. Two aerosol-cloud regimes are considered in this analysis: single-layer stratocumulus cloud with below-cloud aerosol concentrations (N{sub a}) below 300 cm{sup -3} on April 8 and April 26-27 (clean cases); and inhomogeneous layered cloud with N{sub a} > 500 cm{sup -3} below cloud base on April 19-20, concurrent with a biomass burning episode (polluted cases). Vertical profiles through cloud in each regime are used to determine average cloud microphysical and optical properties. Positive correlations between the cloud droplet effective radius (Re) and cloud optical depth ({tau}) are observed for both clean and polluted cases, which are characteristic of optically-thin, non-precipitating clouds. Average Re values for each case are {approx} 6.2 {mu}m, despite significantly higher droplet number concentrations (Nd) in the polluted cases. The apparent independence of Re and Nd simplifies the description of indirect effects, such that {tau} and the cloud albedo (A) can be described by relatively simple functions of the cloud liquid water path. Adiabatic cloud parcel model simulations show that the marked differences in Na between the regimes account largely for differences in droplet activation, but that the properties of precursor aerosol also play a role, particularly for polluted cases where competition for vapour amongst the more numerous particles limits activation to larger and/or more hygroscopic particles. The similarity of Re for clean and polluted cases is attributed to compensating droplet growth processes for different initial droplet size distributions.

Earle, Michael; Liu, Peter S.; Strapp, J. Walter; Zelenyuk, Alla; Imre, D.; McFarquhar, Greg; Shantz, Nicole C.; Leaitch, W. R.

2011-11-04T23:59:59.000Z

105

Experiments related to the resuspension of aerosols during hydrogen burns  

SciTech Connect (OSTI)

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.

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

1987-01-01T23:59:59.000Z

106

Optical  

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

Optical Optical fiber-based single-shot picosecond transient absorption spectroscopy Andrew R. Cook a͒ and Yuzhen Shen Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973, USA ͑Received 27 January 2009; accepted 29 May 2009; published online 17 July 2009͒ A new type of single-shot transient absorption apparatus is described based on a bundle of optical fibers. The bundle contains 100 fibers of different lengths, each successively giving ϳ15 ps longer optical delay. Data are collected by imaging light from the exit of the bundle into a sample where it is overlapped with an electron pulse or laser excitation pulse, followed by imaging onto a charge coupled device ͑CCD͒ detector where the intensity of light from each fiber is measured simultaneously. Application to both ultrafast pump-probe spectroscopy and pulse radiolysis is demonstrated. For pulse

107

Optics  

Science Journals Connector (OSTI)

Optical components such as lenses, mirrors and diffraction gratings are widely used in many inspection systems. These include not only those for visual inspection with CCD cameras, but also in areas of distanc...

C. Loughlin

1993-01-01T23:59:59.000Z

108

ARM - Measurement - Aerosol absorption  

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

absorption absorption ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol absorption The process in which radiation energy is retained by aerosols. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments AOS : Aerosol Observing System CSPHOT : Cimel Sunphotometer IAP : In-situ Aerosol Profiles (Cessna Aerosol Flights) PSAP : Particle Soot Absorption Photometer PASS : Photoacoustic Soot Spectrometer External Instruments OMI : Ozone Monitoring Instrument

109

ARM - Measurement - Aerosol concentration  

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

concentration concentration ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol concentration A measure of the amount of aerosol particles (e.g. number, mass, volume) per unit volume of air. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments AOS : Aerosol Observing System CSPHOT : Cimel Sunphotometer CPC : Condensation Particle Counter IAP : In-situ Aerosol Profiles (Cessna Aerosol Flights) TDMA : Tandem Differential Mobility Analyzer

110

Development and Characterization of a Thermodenuder for Aerosol Volatility Measurements  

SciTech Connect (OSTI)

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.

Dr. Timothy Onasch

2009-09-09T23:59:59.000Z

111

ARM - Field Campaign - MArine Stratus Radiation Aerosol and Drizzle  

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

govCampaignsMArine Stratus Radiation Aerosol and Drizzle (MASRAD) IOP govCampaignsMArine Stratus Radiation Aerosol and Drizzle (MASRAD) IOP Campaign Links Science Plan AMF Point Reyes Website AMF Point Reyes Data Plots Related Campaigns MASRAD: Pt. Reyes Stratus Cloud and Drizzle Study 2005.07.07, Coulter, AMF MASRAD: Cloud Condensate Nuclei Chemistry Measurements 2005.07.01, Berkowitz, AMF MASRAD - Aerosol Optical Properties 2005.06.29, Strawa, AMF MASRAD:Sub-Micron Aerosol Measurements 2005.06.20, Wang, AMF MASRAD: Cloud Study from the 2NFOV at Pt. Reyes Field Campaign 2005.06.02, Wiscombe, AMF Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : MArine Stratus Radiation Aerosol and Drizzle (MASRAD) IOP 2005.03.14 - 2005.09.14 Website : http://www.arm.gov/sites/amf/pye/ Lead Scientist : Mark Miller

112

Carbonaceous Aerosols and Radiative...  

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

and absorption of light by aerosols. At the ground sites, a new Humidigraph, a Cloud Condensation Nuclei Counter, a Scanning Mobility Particle Sizer, and an upgraded 915-MHz...

113

BNL | Aerosol Lifecycle IOP  

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

Program Program Aerosol Life Cycle IOP The primary objectives that make up the Aerosol Life Cycle IOP can be broken down into three categories: Scientific; Logistical; and GVAX preparation. Scientific Objectives The science goals are to conduct intensive aerosol observations in a region exposed to anthropogenic, biogenic, and marine emissions with atmospheric processing times depending on air mass trajectories and time of day. Take advantage of new instruments in the MAOS (e.g., SP2, HR-PTRMS, ACSM, Trace Gas Suite, PASS-3, Aethelometer, UHSAS). Within this broad umbrella are embedded three main foci: Aerosol light absorption: How does the aerosol mass absorption coefficient (absorption per unit mass of BC) vary with atmospheric processing? Do observations agree with a shell-core model?

114

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

SciTech Connect (OSTI)

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.

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.

2013-02-07T23:59:59.000Z

115

Aerosol Cans? -Aerosol cans use a pressurized  

E-Print Network [OSTI]

? - The waste generated in the processing of images/photos contains silver. Silver is a toxic heavy metal the product. Propellants are often flammable and/or toxic. Therefore, never store aerosol cans near ignition of this pamphlet. -Carefully transfer the old paint thinner from the one gallon closable can to the 30 gallon metal

Jia, Songtao

116

Variable depth core sampler  

DOE Patents [OSTI]

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.

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

1996-01-01T23:59:59.000Z

117

Variable depth core sampler  

DOE Patents [OSTI]

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.

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

1996-02-20T23:59:59.000Z

118

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

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

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.

Sedlacek, Art

119

ARM - Measurement - Aerosol particle size  

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

particle size particle size ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol particle size Linear size (e.g. radius or diameter) of an aerosol particle. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. Field Campaign Instruments AEROSMASSSPEC : Aerosol Mass Spectrometer CPI : Cloud Particle Imager DRI-GND : Desert Research Institute Ground-Based Aerosol Instruments DRUM-AEROSOL : Drum Aerosol Sampler AEROSOL-TOWER-EML : EML Tower based Aerosol Measurements

120

A World-wide Stratospheric Aerosol Layer  

Science Journals Connector (OSTI)

...Massachusetts An aerosol layer has been identified by a stratospheric balloon and aircraft aerosol collection program. Measurements...Abstract. An aerosol layer has been identified by a stratospheric balloon and aircraft aerosol collection program. Meas-urements...

Christian E. Junge; Charles W. Chagnon; James E. Manson

1961-05-12T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Use of Aeronet Aerosol Retrievals to Calculate Clear-Sky Irradiance at the Surface  

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

AERONET Aerosol Retrievals to AERONET Aerosol Retrievals to Calculate Clear-Sky Irradiance at the Surface G. L. Schuster National Aeronautics and Space Administration Langley Research Center Hampton, Virginia O. Dubovik National Aeronautics and Space Administration Goddard Space Flight Center Laboratory for Terrestrial Physics Greenbelt, Maryland Motivation The worldwide aerosol robotic network (AERONET) of ground-based radiometers was developed (in part) as a satellite validation tool (Holben et al. 1998). These sites utilize spectral sky-scanning radiometers, providing more information for aerosol retrievals than conventional sunphotometer measurements. The use of the almucantar sky radiance scans in conjunction with the aerosol optical thicknesses are the basis of the AERONET Dubovik retrievals, which provide the aerosol size

122

NOTES ON NEUTRON DEPTH PROFILING  

E-Print Network [OSTI]

NOTES ON NEUTRON DEPTH PROFILING by J.K. Shultis Department of Mechanical and Nuclear Engineering College of Engineering Kansas State University Manhattan, Kansas 66506 Dec. 2003 #12;Notes on Neutron Depth Profiling J. Kenneth Shultis December 2003 1 Introduction The purpose of neutron depth profiling

Shultis, J. Kenneth

123

BNL | Aerosol, Cloud, Precipitation Interactions  

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

Cloud-Aerosol-Precipitation Interactions Cloud-Aerosol-Precipitation Interactions Atmospheric aerosols exert important "indirect effects" on clouds and climate by serving as cloud condensation nuclei (CCN) and ice nuclei that affect cloud radiative and microphysical properties. For example, an increase in CCN increases the number concentration of droplets enhances cloud albedo, and suppresses precipitation that alters cloud coverage and lifetime. However, in the case of moist and strong convective clouds, increasing aerosols may increase precipitation and enhance storm development. Although aerosol-induced indirect effects on climate are believed to have a significant impact on global climate change, estimating their impact continues to be one of the most uncertain climate forcings.

124

Jankovic Aerosol Characterization.ppt  

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

Characterization, Characterization, Aerosol Characterization, Interpretation, and Interpretation, and Application of Data Application of Data NSRC Symposium NSRC Symposium July 8, 2008 John Jankovic, CIH CIH Center for Nanophase Materials Sciences Center for Nanophase Materials Sciences Aerosol Characterization, Interpretation, and Aerosol Characterization, Interpretation, and Application of Data Application of Data Department of Energy (DOE) Nanoscale Science Research Centers (NSRC) developing Approach to Nanomaterial ES&H - The CNMS Approach * Establish Exposure Control Guideline (ECG) - Characterize Aerosol * Collect and interpret data * Assign Process to a Control Band Aerosol Particle Characterization * Size distribution (geometric mean and geometric standard deviation related to either mass, surface, or number)

125

ARM Aerosol Working Group Meeting  

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

and MFRSR Measurements ARM STM 2008 Norfolk, VA Connor Flynn 1 , Annette Koontz 1 , Anne Jefferson 2 , Jim Barnard 1 , Sally McFarlane 1 1 Pacific Northwest National Laboratory 2 CIRES, University of Colorado, Boulder Progress towards ARM DOE 2008 Performance Metric 3 & 4 * Produce and make available new continuous time series of aerosol total column depth, based on results from the AMF deployment in Niger, Africa. * Produce and make available new continuous time series of retrieved dust properties, based on results from the AMF deployment in Niger, Africa. 0 100 200 300 400 0 20 40 60 80 100 ITF movement and surface RH % RH day of year (2006) 0 100 200 300 400 0 50 100 150 200 250 300 350 day of year wind direction (N = 0, E = 90) 2 4 6 8 10 12 14 Wind speed m/s 0 100 200 300 1.4 1.6 1.8 2 MFRSR Vo for filter2, Niamey

126

Optical Properties of Secondary Organic Aerosols  

E-Print Network [OSTI]

J. H. Seinfeld, T. J. Wallington, and G. Yarwood (2002), TheJ. H. Seinfeld, T. J. Wallington, and G. Yarwood (2002), The

Kim, Hwajin

2012-01-01T23:59:59.000Z

127

aerosols and climate : uncertainties  

E-Print Network [OSTI]

contributes to creating a level playing field. (BC emissions tradeble like CO2 emissions?) OUTLINE #12;size. policy measures, is even more uncertain (emissions & their chemical fingerprint are uncertain (not just aerosol emissions, not just climate impacts) OUTLINE #12;- Standardization doesn't reduce

128

Aerosols in a Changing Atmosphere: From Detailed Aerosol Microphysics to  

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

Aerosols in a Changing Atmosphere: From Detailed Aerosol Microphysics to Aerosols in a Changing Atmosphere: From Detailed Aerosol Microphysics to Policy Applications Speaker(s): Susanne Bauer Date: December 6, 2011 - 4:00pm Location: 90-4133 Seminar Host/Point of Contact: Surabi Menon The anthropogenic increase in aerosol concentrations since preindustrial times and its net cooling effect on the atmosphere is thought to mask some of the greenhouse gas induced warming. Although the overall effect of aerosols on solar radiation and clouds is most certainly negative, some individual forcing agents and feedbacks have positive forcing effects. Recent studies have tried to identify some of those positive forcing agents and their individual emission sectors, However, understanding the net effect of multi-source emitting sectors and the involved cloud feedbacks is

129

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

SciTech Connect (OSTI)

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 22N and 95 to 107E. 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.

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

2014-10-12T23:59:59.000Z

130

CHRISTINE Code for High ResolutIon Satellite mapping of optical ThIckness and Ngstrom Exponent. Part I: Algorithm and code  

Science Journals Connector (OSTI)

Previously developed DTA (Differential Textural Analysis) and SMA (Satellite Mapping of Aerosols) image processing codes address aerosol optical thickness (AOT) retrieval and mapping over urban areas by applying the contrast reduction principle to single ... Keywords: ngstrom, Aerosol optical thickness, Air pollution, Contrast reduction, High resolution

Nicolas I. Sifakis; Christos Iossifidis

2014-01-01T23:59:59.000Z

131

ARM - Mobile Aerosol Observing System  

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

FacilitiesMobile Aerosol Observing System FacilitiesMobile Aerosol Observing System AMF Information Science Architecture Baseline Instruments AMF1 AMF2 AMF3 Data Operations AMF Fact Sheet Images Contacts AMF Deployments Hyytiälä, Finland, 2014 Manacapuru, Brazil, 2014 Oliktok Point, Alaska, 2013 Los Angeles, California, to Honolulu, Hawaii, 2012 Cape Cod, Massachusetts, 2012 Gan Island, Maldives, 2011 Ganges Valley, India, 2011 Steamboat Springs, Colorado, 2010 Graciosa Island, Azores, 2009-2010 Shouxian, China, 2008 Black Forest, Germany, 2007 Niamey, Niger, 2006 Point Reyes, California, 2005 Mobile Aerosol Observing System Intensive aerosol observations conducted on the campus of Brookhaven National Laboratory on Long Island, New York, using the ARM Mobile Aerosol Observing System. Intensive aerosol observations conducted on the campus of Brookhaven

132

Experimental study of nuclear workplace aerosol samplers  

E-Print Network [OSTI]

LITERATURE REVIEW Aerosol Losses in an Inlet . Aerosol Losses in a Transport System Aerosol Losses in CAMs Critical Flow Venturi 8 13 15 16 EXPERIMENT PROCEDURE 18 CAM Evaluation Consideration FAS Evaluation Consideration Test Protocol Mixing... Chamber Setup High Speed Aerosol Wind Tunnel Setup Low Speed Aerosol Wind Tunnel Setup Critical Flow Venturi 18 19 21 22 24 25 27 RESULTS AND DISCUSSION Page 28 Aerosol Penetration through Transport Systems and CAM Areal Uniformity Deposits...

Parulian, Antony

2012-06-07T23:59:59.000Z

133

EMSL: Science: Atmospheric Aerosol Systems  

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

Atmospheric Aerosol Systems Atmospheric Aerosol Systems atmospheric logo Nighttime enhancement of nitrogen-containing organic compounds, or NOC Observed nighttime enhancement of nitrogen-containing organic compounds, or NOC, showed evidence of being formed by reactions that transform carbonyls into imines. The Atmospheric Aerosol Systems Science Theme focuses on understanding the chemistry, physics and molecular-scale dynamics of aerosols for model parameterization to improve the accuracy of climate model simulations and develop a predictive understanding of climate. By elucidating the role of natural and anthropogenic regional and global climate forcing mechanisms, EMSL can provide DOE and others with the ability to develop cost-effective strategies to monitor, control and mitigate them.

134

Two-Column Aerosol Project  

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

help find the answer, the Department of Energy's Atmospheric Radiation Measurement (ARM) Climate Research Facility is conducting the Two-Column Aerosol Project (TCAP) at Cape Cod...

135

ARM Cloud Aerosol Precipitation Experiment  

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

Satellite Observation CAS Cloud Aerosol Spectrometer CCN Cloud Condensation Nuclei CIP Cloud Imaging Probe CPC Condensation Particle Counter CSPHOT Cimel sunphotometer CVI...

136

Molecular Characterization of Biomass Burning Aerosols Using...  

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

Biomass Burning Aerosols Using High Resolution Mass Spectrometry. Molecular Characterization of Biomass Burning Aerosols Using High Resolution Mass Spectrometry. Abstract: Chemical...

137

Aerosol mass spectrometry systems and methods  

DOE Patents [OSTI]

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.

Fergenson, David P.; Gard, Eric E.

2013-08-20T23:59:59.000Z

138

CARES: Carbonaceous Aerosol and Radiative Effects Study Operations Plan  

SciTech Connect (OSTI)

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.

Zaveri, RA; Shaw, WJ; Cziczo, DJ

2010-07-12T23:59:59.000Z

139

Mapping Indigenous Depth of Place  

E-Print Network [OSTI]

AMERICAN INDIAN CULTURE AND RESEARCH JOURNAL 32:3 (2008) 107126 107 Mapping Indigenous Depth of Place MARGARET WICKENS PEARCE AND RENEE PUALANI LOUIS INTRODUCTION Indigenous communities have successfully used Western geospatial technolo- gies (GT... of geog- raphy at Ohio University in Athens, Ohio. Renee Pualani Louis is Hawaiian and recently completed her doctorate in geography at the University of Hawaii at Manoa, Honolulu, Hawaii. Published as M. Pearce and R. Louis. Mapping Indigenous depth...

Pearce, Margaret Wickens; Louis, Renee Pualani

2008-11-01T23:59:59.000Z

140

4, 58315854, 2004 Fluorescing aerosol  

E-Print Network [OSTI]

released by combustion into the atmosphere absorbs radiation and therefore heats the climate counteracting such as polycyclic aromatic hydrocarbons sticking to the aerosol particles, or bioaerosol such as bacteria, spores) or by combustion processes (soot), or they form in situ by gas to particle conversion, like sulphate aerosol. While

Paris-Sud XI, Université de

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141

Parameterizations of Cloud Microphysics and Indirect Aerosol Effects  

SciTech Connect (OSTI)

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

Tao, Wei-Kuo [NASA/GSFC] [NASA/GSFC

2014-05-19T23:59:59.000Z

142

Observations of the first aerosol indirect effect in shallow cumuli  

SciTech Connect (OSTI)

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.

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

2011-02-08T23:59:59.000Z

143

Aerosol Laboratory - Nuclear Engineering Division (Argonne)  

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

Capabilities > Engineering Capabilities > Engineering Experimentation > Aerosol Laboratory Capabilities Engineering Experimentation Reactor Safety Experimentation Aerosol Experiments System Components Laser Applications Robots Applications Other Facilities Other Capabilities Work with Argonne Contact us For Employees Site Map Help Join us on Facebook Follow us on Twitter NE on Flickr Aerosol Laboratory The Aerosol Laboratory (AL) houses equipment to measure and record the physical parameters necessary to characterize the formation and transport of aerosols. Bookmark and Share The Aerosol Laboratory (AL) has extensive analytic and experimental capabilities to characterize the formation and transport of aerosols formed from the condensation of vapors. Computer codes have been developed to

144

Airborne measurements of carbonaceous aerosols in southern Africa during  

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

Airborne measurements of carbonaceous aerosols in southern Africa during Airborne measurements of carbonaceous aerosols in southern Africa during the dry, biomass burning season Title Airborne measurements of carbonaceous aerosols in southern Africa during the dry, biomass burning season Publication Type Journal Article LBNL Report Number LBNL-50880 Year of Publication 2003 Authors Kirchstetter, Thomas W., Tihomir Novakov, and Peter V. Hobbs Journal Journal of Geophysical Research - Atmospheres Keywords black carbon, evolved gas analysis, light absorption, organic carbon, positive sampling artifact, SAFARI Abstract Particulate matter collected aboard the University of Washington's Convair-580 research aircraft over southern Africa during the dry, biomass burning season was analyzed for total carbon, organic carbon, and black carbon contents using thermal and optical methods. Samples were collected in smoke plumes of burning savanna and in regional haze. A known artifact, produced by the adsorption of organic gases on the quartz filter substrates used to collect the particulate matter samples, comprised a significant portion of the total carbon collected. Consequently, conclusions derived from the data are greatly dependent on whether or not organic carbon concentrations are corrected for this artifact. For example, the estimated aerosol co-albedo (1 - single scattering albedo), which is a measure of aerosol absorption, of the biomass smoke samples is 60% larger using corrected organic carbon concentrations. Thus, the corrected data imply that the biomass smoke is 60% more absorbing than do the uncorrected data. The black carbon to (corrected) organic carbon mass ratio (BC/OC) of smoke plume samples (0.18±0.06) is lower than that of samples collected in the regional haze (0.25±0.08). The difference may be due to mixing of biomass smoke with background air characterized by a higher BC/OC ratio. A simple source apportionment indicates that biomass smoke contributes about three-quarters of the aerosol burden in the regional haze, while other sources (e.g., fossil fuel burning) contribute the remainder.

145

Evidence that the spectral dependence of light absorption by aerosols is  

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

Evidence that the spectral dependence of light absorption by aerosols is Evidence that the spectral dependence of light absorption by aerosols is affected by organic carbon Title Evidence that the spectral dependence of light absorption by aerosols is affected by organic carbon Publication Type Journal Article LBNL Report Number LBNL-55056 Year of Publication 2004 Authors Kirchstetter, Thomas W., Tihomir Novakov, and Peter V. Hobbs Journal Journal of Geophysical Research: Atmospheres Volume 109 Issue D21 Keywords aerosol light absorption, biomass burning, organic carbon Abstract The wavelength dependence of light absorption by aerosols collected on filters is investigated throughout the near-ultraviolet to near-infrared spectral region. Measurements were made using an optical transmission method. Aerosols produced by biomass combustion, including wood and savanna burning, and by motor vehicles, including diesel trucks, are included in the analysis. These aerosol types were distinguished by different wavelength (λ) dependences in light absorption. Light absorption by the motor vehicle aerosols exhibited relatively weak wavelength dependence; absorption varied approximately as λ-1, indicating that black carbon (BC) was the dominant absorbing aerosol component. By contrast, the biomass smoke aerosols had much stronger wavelength dependence, approximately λ-2. The stronger spectral dependence was the result of enhanced light absorption at wavelengths shorter than 600 nm and was largely reduced when much of the sample organic carbon (OC) was extracted by dissolution in acetone. This indicates that OC in addition to BC in the biomass smoke aerosols contributed significantly to measured light absorption in the ultraviolet and visible spectral regions and that OC in biomass burning aerosols may appreciably absorb solar radiation. Estimated absorption efficiencies and imaginary refractive indices are presented for the OC extracted from biomass burning samples and the BC in motor vehicle-dominated aerosol samples. The uncertainty of these constants is discussed. Overall, results of this investigation show that low-temperature, incomplete combustion processes, including biomass burning, can produce light-absorbing aerosols that exhibit much stronger spectral dependence than high-temperature combustion processes, such as diesel combustion.

146

ARM - Surface Aerosol Observing System  

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

FacilitiesSurface Aerosol Observing System FacilitiesSurface Aerosol Observing System AMF Information Science Architecture Baseline Instruments AMF1 AMF2 AMF3 Data Operations AMF Fact Sheet Images Contacts AMF Deployments Hyytiälä, Finland, 2014 Manacapuru, Brazil, 2014 Oliktok Point, Alaska, 2013 Los Angeles, California, to Honolulu, Hawaii, 2012 Cape Cod, Massachusetts, 2012 Gan Island, Maldives, 2011 Ganges Valley, India, 2011 Steamboat Springs, Colorado, 2010 Graciosa Island, Azores, 2009-2010 Shouxian, China, 2008 Black Forest, Germany, 2007 Niamey, Niger, 2006 Point Reyes, California, 2005 Surface Aerosol Observing System The ARM Mobile Facility (AMF) is equipped to quantify the interaction between clouds and aerosol particles. A counter-flow virtual impactor (CVI) is used to selectively sample cloud drops. The CVI takes advantage of the

147

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

ScienceCinema (OSTI)

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.

None

2014-06-03T23:59:59.000Z

148

Atmospheric Plasma Jet Machining of Optical Surfaces  

Science Journals Connector (OSTI)

Deterministic surface machining with high spatial resolution and nanometric depth accuracy is urgently required in the fabrication of high-end optics. Thus, plasma jet tools with...

Bhm, Georg; Eichentopf, Inga-Maria; Arnold, Thomas

149

Ultrasonic material hardness depth measurement  

DOE Patents [OSTI]

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.

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

1997-01-01T23:59:59.000Z

150

About EffectiveŽ Height of the Aerosol Atmosphere in Visible and IR Wavelength Range  

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

"Effective" Height of the Aerosol Atmosphere in "Effective" Height of the Aerosol Atmosphere in Visible and IR Wavelength Range V. N. Uzhegov, D. M. Kabanov, M. V. Panchenko, Yu. A. Pkhalagov, and S. M. Sakerin Institute of Atmospheric Optics Tomsk, Russia Introduction Aerosol component of the atmosphere is one of the important factors affecting the radiation budget of the space - atmosphere - underlying surface system in visible and infrared (IR) wavelength ranges. It is extremely important to take into account the contribution of this component into the extinction of solar radiation under cloudless sky conditions. Sometimes it is important to know not only the total value of the aerosol component of extinction, but also to have the possibility to estimate the "effective" height of

151

Anisotropic poststack depth migration, eastern Venezuela  

SciTech Connect (OSTI)

It is known that in areas with significant shale content, the isotropic assumption in depth migration is not correct, and this can lead to incorrect depth positioning if not properly accounted for. In this paper, we performed isotropic and anisotropic poststack depth migrations on a dataset from Eastern Venezuela to study the influence of anisotropy over the depth migration process. When interval velocities derived from surface seismic are compared with those velocities from check shots, significant differences are observed specially for depths associated with a thick sequence of shales identified in the area. These differences in interval velocities are used to obtain estimations of the anisotropic constants used in the anisotropic depth migration process. The anisotropic depth-migrated section allows to position correctly in depth known geological markers identified in well logs, while the results in the isotropic depth-migration show some mismatch with the depths obtained from well-log information.

Uzcategui, O.J.; Mujica, D.L.

1995-12-31T23:59:59.000Z

152

Direct and semi-direct aerosol effects of Southern African1 biomass burning aerosol2  

E-Print Network [OSTI]

1 Direct and semi-direct aerosol effects of Southern African1 biomass burning aerosol2 Naoko effects of biomass burning aerosols from Southern African fires9 during July-October are investigated region the overall TOA radiative effect from the23 biomass burning aerosols is almost zero due

Wood, Robert

153

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

SciTech Connect (OSTI)

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.

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

2012-08-22T23:59:59.000Z

154

Techniques and Methods Used to Determine the Aerosol Best Estimate Value-Added Product at SGP Central Facility  

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

Determine the Aerosol Best Estimate Value-Added Product at SGP Central Facility C. Sivaraman, D. D. Turner, and C. J. Flynn Pacific Northwest National Laboratory Richland, Washington Objective Profiles of aerosol optical properties are needed for radiative closure exercises such as the broadband heating rate profile (BBHRP) project (Mlawer et al. 2002) and the Shortwave Quality Measurement Experiment (QME). Retrieving cloud microphysical properties using radiation measurements in the shortwave, such as the spectral retrieval technique described in Daniel et al. (2002), also require the optical properties of the aerosols so that they can be accounted for in the retrieval process. The objective of the aerosol best estimate (ABE) value-added procedure (VAP) is to provide profiles of

155

ARM - Evaluation Product - Organic Aerosol Component VAP  

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

ProductsOrganic Aerosol Component VAP ProductsOrganic Aerosol Component VAP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Organic Aerosol Component VAP 2011.01.08 - 2012.03.24 Site(s) SGP General Description Organic aerosol (OA, i.e., the organic fraction of particles) accounts for 10-90% of the fine aerosol mass globally and is a key determinant of aerosol radiative forcing. But atmospheric OA is poorly characterized and its life cycle insufficiently represented in models. As a result, current models are unable to simulate OA concentrations and properties. This deficiency represents a large source of uncertainty in the quantification of aerosol direct and indirect effects and the prediction of future climate change. The Organic Aerosol Component (OACOMP) value-added product (VAP) uses

156

Reflective Aerosols and the Greenhouse Effect  

Science Journals Connector (OSTI)

The contributions of atmospheric aerosols to add to either a climate-warming effect or climate-cooling effect depend on the chemical composition of the aerosol and the local environment. The best estimation is...

Kathryn E. Kautzman

2014-07-01T23:59:59.000Z

157

Antiviral therapy with small particle aerosols  

Science Journals Connector (OSTI)

The generation and use of small particle aqueous aerosols (1.23 m aerodynamic mass median diameter, GSD=2.0 m) containing ribavirin is described. Administered via aerosol, ribavirin will be deposited rather ...

V. Knight; B. Gilbert

1988-12-01T23:59:59.000Z

158

Active Spectral Nephelometry in Studies of the Condensational Activity of Submicron Aerosol  

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

Active Spectral Nephelometry in Studies of the Active Spectral Nephelometry in Studies of the Condensational Activity of Submicron Aerosol M. V. Panchenko, S. A. Terpugova, and V. S. Kozlov Institute of Atmospheric Optics Russian Academy of Sciences Tomsk, Russia M. A. Sviridenkov A. M. Obukhov Institute of Atmospheric Physics Russian Academy of Sciences Moscow, Russia A. S. Kozlov Institute of Chemical Kinetics and Combustion Russian Academy of Sciences Novosibirsk, Russia Introduction Water vapor condensation and evaporation are among the main processes of the atmospheric aerosol transformation essentially affecting its optical and radiative characteristics. Most of the known methods for investigating the aerosol condensation activity are based on measurements of only the changes in the

159

2, 20952131, 2002 Below-cloud aerosol  

E-Print Network [OSTI]

). In addition, the understanding of wet removal processes remains crucial in local and regional pollutionACPD 2, 2095­2131, 2002 Below-cloud aerosol removal C. Andronache Title Page Abstract Introduction-cloud aerosol removal by rainfall for observed aerosol size distributions C. Andronache Boston College, Chestnut

Paris-Sud XI, Université de

160

6, 93519388, 2006 Aerosol-cloud  

E-Print Network [OSTI]

ACPD 6, 9351­9388, 2006 Aerosol-cloud interaction inferred from MODIS and models G. Myhre et al Chemistry and Physics Discussions Aerosol-cloud interaction inferred from MODIS satellite data and global 6, 9351­9388, 2006 Aerosol-cloud interaction inferred from MODIS and models G. Myhre et al. Title

Paris-Sud XI, Université de

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

ARM - Measurement - Aerosol backscattered radiation  

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

backscattered radiation backscattered radiation ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol backscattered radiation The scattering of radiant energy into the hemisphere of space bounded by a plane normal to the direction of the incident radiation and lying on the same side as the incident ray. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments AOS : Aerosol Observing System MPL : Micropulse Lidar NEPHELOMETER : Nephelometer

162

Final Report for LDRD Project ''A New Era of Research in Aerosol/Cloud/Climate Interactions at LLNL''  

SciTech Connect (OSTI)

Observations of global temperature records seem to show less warming than predictions of global warming brought on by increasing concentrations of CO{sub 2} and other greenhouse gases. One of the reasonable explanations for this apparent inconsistency is that the increasing concentrations of anthropogenic aerosols may be partially counteracting the effects of greenhouse gases. Aerosols can scatter or absorb the solar radiation, directly change the planetary albedo. Aerosols, unlike CO{sub 2}, may also have a significant indirect effect by serving as cloud condensation nuclei (CCN). Increases in CCN can result in clouds with more but smaller droplets, enhancing the reflection of solar radiation. Aerosol direct and indirect effects are a strong function of the distributions of all aerosol types and the size distribution of the aerosol in question. However, the large spatial and temporal variabilities in the concentration, chemical characteristics, and size distribution of aerosols have made it difficult to assess the magnitude of aerosol effects on atmospheric radiation. These variabilities in aerosol characteristics as well as their effects on clouds are the leading sources of uncertainty in predicting future climate variation. Inventory studies have shown that the present-day anthropogenic emissions contribute more than half of fine particle mass primarily due to sulfate and carbonaceous aerosols derived from fossil fuel combustion and biomass burning. Parts of our earlier studies have been focused on developing an understanding of global sulfate and carbonaceous aerosol abundances and investigating their climate effects [Chuang et al., 1997; Penner et al., 1998]. We have also modeled aerosol optical properties to account for changes in the refractive indices with relative humidity and dry aerosol composition [Grant et al., 1999]. Moreover, we have developed parameterizations of cloud response to aerosol abundance for use in global models to evaluate the importance of aerosol/cloud interactions on climate forcing [Chuang and Penner, 1995]. Our research has been recognized as one of a few studies attempting to quantify the effects of anthropogenic aerosols on climate in the IPCC Third Assessment Report [IPCC, 2001]. Our previous assessments of aerosol climate effects were based on a general circulation model (NCAR CCM1) fully coupled to a global tropospheric chemistry model (GRANTOUR). Both models, however, were developed more than a decade ago. The lack of advanced physics representation and techniques in our current models limits us from further exploring the interrelationship between aerosol, cloud, and climate variation. Our objective is to move to a new era of aerosol/cloud/climate modeling at LLNL by coupling the most advanced chemistry and climate models and by incorporating an aerosol microphysics module. This modeling capability will enable us to identify and analyze the responsible processes in aerosol/cloud/climate interactions and therefore, to improve the level of scientific understanding for aerosol climate effects. This state-of-the-art coupled models will also be used to address the relative importance of anthropogenic and natural emissions in the spatial pattern of aerosol climate forcing in order to assess the potential of human induced climate change.

Chuang, C; Bergman, D J; Dignon, J E; Connell, P S

2002-01-31T23:59:59.000Z

163

AEROSOL DIRECT RADIATIVE EFFECTS OVER THE NORTHWEST ATLANTIC, NORTHWEST PACIFIC, AND NORTH INDIAN OCEANS  

E-Print Network [OSTI]

AEROSOL DIRECT RADIATIVE EFFECTS OVER THE NORTHWEST ATLANTIC, NORTHWEST PACIFIC, AND NORTH INDIAN, NORTHWEST PACIFIC, AND NORTH INDIAN OCEANS: ESTIMATES BASED ON IN-SITU CHEMICAL AND OPTICAL MEASUREMENTS, Y.24 , Tang, Y.25 , Weber, R. J.26 , and Wu, Y.27 1 NOAA/PMEL, 7600 Sand Point Way NE, Seattle, WA

164

Light Scattering by Ice Crystals and Mineral Dust Aerosols in the Atmosphere  

E-Print Network [OSTI]

of cirrus clouds is demonstrated and explained theoretically, which provides guidance in the calibration algorithm for 1.064-m channel on the Calipso lidar. Dust aerosols have no particular morphology. To develop an approach to modeling the optical...

Bi, Lei

2012-07-16T23:59:59.000Z

165

Atmospheric Aerosols Aging Involving Organic Compounds and Impacts on Particle Properties  

E-Print Network [OSTI]

) and chemical reactions (oxidation of particles by gas-phase oxidants and heterogeneous reactions between gas molecules and particles).5 For example, when initially formed, soot particles are hydrophobic and fractal in morphology, with low effective density... particles have a ? value of 1.0; whereas fractal ones will have ? > 1.0. Measurements of Aerosol Optical Properties The optical system consisted of a commercial integrating Nephelometer (Model 3563, TSI) and a CRDS connected in series.20 The particles...

Qiu, Chong

2013-02-01T23:59:59.000Z

166

Review of models applicable to accident aerosols  

SciTech Connect (OSTI)

Estimations of potential airborne-particle releases are essential in safety assessments of nuclear-fuel facilities. This report is a review of aerosol behavior models that have potential applications for predicting aerosol characteristics in compartments containing accident-generated aerosol sources. Such characterization of the accident-generated aerosols is a necessary step toward estimating their eventual release in any accident scenario. Existing aerosol models can predict the size distribution, concentration, and composition of aerosols as they are acted on by ventilation, diffusion, gravity, coagulation, and other phenomena. Models developed in the fields of fluid mechanics, indoor air pollution, and nuclear-reactor accidents are reviewed with this nuclear fuel facility application in mind. The various capabilities of modeling aerosol behavior are tabulated and discussed, and recommendations are made for applying the models to problems of differing complexity.

Glissmeyer, J.A.

1983-07-01T23:59:59.000Z

167

New depths with mobile rig  

SciTech Connect (OSTI)

Magee-Poole Drilling Company, a drilling contractor operating out of the south Texas drilling center of Alice, claims it operates the largest mobile drilling rig in the world. That is, it's the only wheel mounted portable rig that drills to 16,000 feet with 4 1/2-inch drill pipe - at least 3000 feet deeper than the previous mobile drilling rig ratings. The unit is designated the Ingersoll-Rand 1500 Series. What's more significant, according to co-owner Don Magee, is that the rig's portability gets the rotary table turning to the right sooner; it drills more footage per year. It rigs up in 1 1/2 days versus 3 to 4 days for a conventional skid type rig normally used at these depths. The unit's compact arrangement, with more components combined into single loads, makes possible its higher mobility. A conventional skid rig might require 25 to 30 truckloads to move the rig components, mud system, fuel and water tank, houses for utilities, storage and crew change, generators, and drill pipe. The new rig moves in anywhere from four to nine loads less. Further, the rig components weigh less without sacrificing durability.

Not Available

1982-03-01T23:59:59.000Z

168

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

E-Print Network [OSTI]

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...

Benoit, Mark David

2013-02-06T23:59:59.000Z

169

ARM - Field Campaign - Two-Column Aerosol Project (TCAP)  

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

govCampaignsTwo-Column Aerosol Project (TCAP) govCampaignsTwo-Column Aerosol Project (TCAP) Campaign Links TCAP website Related Campaigns Two-Column Aerosol Project (TCAP): Field Evaluation of Real-time Cloud OD Sensor TWST 2013.04.15, Scott, AMF Two-Column Aerosol Project (TCAP): Winter Aerosol Effects on Cloud Formation 2013.02.04, Cziczo, AMF Two-Column Aerosol Project (TCAP): CU GMAX-DOAS Deployment 2012.07.15, Volkamer, AMF Two-Column Aerosol Project (TCAP): Aerosol Light Extinction Measurements 2012.07.15, Dubey, AMF Two-Column Aerosol Project (TCAP): Aerial Campaign 2012.07.07, Berg, AAF Two-Column Aerosol Project (TCAP): Aerodynamic Particle Sizer 2012.07.01, Berg, AMF Two-Column Aerosol Project (TCAP): KASPRR Engineering Tests 2012.07.01, Mead, AMF Two-Column Aerosol Project (TCAP): Airborne HSRL and RSP Measurements

170

Direct and semidirect aerosol effects of southern African biomass burning aerosol  

E-Print Network [OSTI]

Direct and semidirect aerosol effects of southern African biomass burning aerosol Naoko Sakaeda,1 2011; published 21 June 2011. [1] Direct and semidirect radiative effects of biomass burning aerosols static stability. Over the entire region the overall TOA radiative effect from the biomass burning

Wood, Robert

171

Separating Cloud Forming Nuclei from Interstitial Aerosol  

SciTech Connect (OSTI)

It has become important to characterize the physicochemical properties of aerosol that have initiated the warm and ice clouds. The data is urgently needed to better represent the aerosol-cloud interaction mechanisms in the climate models. The laboratory and in-situ techniques to separate precisely the aerosol particles that act as cloud condensation nuclei (CCN) and ice nuclei (IN), termed as cloud nuclei (CN) henceforth, have become imperative in studying aerosol effects on clouds and the environment. This review summarizes these techniques, design considerations, associated artifacts and challenges, and briefly discusses the need for improved designs to expand the CN measurement database.

Kulkarni, Gourihar R.

2012-09-12T23:59:59.000Z

172

Carbonaceous Aerosol Study Using Advanced Particle Instrumentation  

E-Print Network [OSTI]

particles from the combustion of biomass fuels. Environ.range transport of biomass combustion aerosols. Environ.during the open combustion of biomass in the laboratory, J.

Qi, Li

2010-01-01T23:59:59.000Z

173

Comparative Analysis of Urban Atmospheric Aerosol by Particle...  

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

Analysis of Urban Atmospheric Aerosol by Particle-Induced X-ray Emission (PIXE), Proton Elastic Scattering Analysis Comparative Analysis of Urban Atmospheric Aerosol by...

174

The Two-Column Aerosol Project Definitions TCAP Educational  

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

What's the big deal about aerosols? The Two-Column Aerosol Project Definitions TCAP Educational Outreach Activity About ARM: The Atmospheric Radiation Measurement (ARM) Climate...

175

Reduction in biomass burning aerosol light absorption upon humidificat...  

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

in biomass burning aerosol light absorption upon humidification: Roles of inorganically-induced hygroscopicity, Reduction in biomass burning aerosol light absorption upon...

176

The Indirect and Semi-Direct Aerosol Campaign  

SciTech Connect (OSTI)

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

Ghan, Steve

2014-03-24T23:59:59.000Z

177

Overview of the COPS Aerosol and Cloud Microphysics (ACM) Subgroup...  

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

properties of orographically induced clouds and how do these depend on dynamics, thermodynamics, and aerosol microphysics? * What is the role of aerosols and changing cloud...

178

Molecular Chemistry of Organic Aerosols Through the Application...  

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

Chemistry of Organic Aerosols Through the Application of High Resolution Mass Spectrometry. Molecular Chemistry of Organic Aerosols Through the Application of High Resolution Mass...

179

Split image optical display  

DOE Patents [OSTI]

A video image is displayed from an optical panel by splitting the image into a plurality of image components, and then projecting the image components through corresponding portions of the panel to collectively form the image. Depth of the display is correspondingly reduced.

Veligdan, James T. (Manorville, NY)

2007-05-29T23:59:59.000Z

180

Recommended Practice: Defense-in-Depth  

Broader source: Energy.gov (indexed) [DOE]

Report # INL/EXT-06-11478 Report # INL/EXT-06-11478 Control Systems Cyber Security: Defense in Depth Strategies May 2006 Prepared by Idaho National Laboratory Recommended Best Practice: Defense in Depth 2 Table of Contents Keywords............................................................................................................................. 3 Introduction......................................................................................................................... 3 Background ......................................................................................................................... 3 Overview of Contemporary Control System Architectures................................................. 4 Security Challenges in Control Systems .............................................................................

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Source Attribution of Light Absorbing Aerosol in Arctic Snow  

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

Source Attribution of Light Absorbing Source Attribution of Light Absorbing Aerosol in Arctic Snow (Preliminary analysis of 2008-2009 data) Outline * Receptor modeling overview * Results from 2007 data set * New goals arising from analysis of 2007 data * New data for 2008 * New data for 2009 * Tentative conclusions * Future analysis i Factor profiles from 2007 analysis Source attribution of Black Carbon from 2007 analysis Goals/Issues suggested by the analysis of the 2007 data set * Are there seasonal differences in the source strengths? * Are there other LAA chemical components besides black carbon. What are their sources? * Can the various data sets available (e.g., 2007, 2008, 2009) be combined in a single large PMF analysis 2008 Data Set For Receptor Analysis * 42 samples from Eastern Siberia including 4 depth profiles

182

BNL | Mobile Aerosol Observing System (MAOS)  

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

Mobile Aerosol Observing System (MAOS) Mobile Aerosol Observing System (MAOS) The Mobile Aerosol Observing System (MAOS) is a platform and instrument suite for Intensive Operation Periods (IOPs) to conduct in situ measurements of aerosols and their precursors. MAOS is part of the ARM Climate Research Facility. Physically MAOS is contained in two 20' SeaTainers custom adapted to provide a sheltered laboratory environment for operators and instruments even under harsh conditions. The two structures are designated MAOS-A and MAOS-C for Aerosol and Chemistry respectively. Although independent, with separate data systems, inlets and power distribution, the two structures are normally a single operating unit. The two enclosures comprising MAOS are designed for rapid deployment. All components (except for the Radar Wind Profiler) are transported internally

183

The Opposed Migration Aerosol Classifier (OMAC)  

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

The Opposed Migration Aerosol Classifier (OMAC) The Opposed Migration Aerosol Classifier (OMAC) Speaker(s): Harmony Gates Date: February 22, 2007 - 12:00pm Location: 90-4133 Seminar Host/Point of Contact: Melissa Lunden A new differential mobility classifier will be described. The instrument classifies aerosol particles in a channel flow between porous (or screen) electrodes. The aerosol enters the channel parallel to the porous electrodes, while a larger, particle-free cross-flow enters through one of the porous electrode. A potential difference between electrodes causes the charged aerosol particles to migrate upstream against the cross-flow. Only particles whose upward migration velocity balances the cross flow will be transmitted along the path of the classifier. Simulations of the OMAC show that it should give the same resolution at the traditional

184

Single-scattering properties of tri-axial ellipsoidal mineral dust aerosols: A database for application to radiative transfer calculations  

E-Print Network [OSTI]

Single-scattering properties of tri-axial ellipsoidal mineral dust aerosols: A database Applications and Research, Camp Spring, MD 20746, USA a r t i c l e i n f o Article history: Received 14 Optical properties Database a b s t r a c t This paper presents a user-friendly database software package

Liou, K. N.

185

Global observations of desert dust and biomass burning aerosols  

E-Print Network [OSTI]

Global observations of desert dust and biomass burning aerosols Martin de Graaf KNMI #12; Outline · Absorbing Aerosol Index - Theory · Absorbing Aerosol Index - Reality · Biomass burning.6 Biomass burning over Angola, 09 Sep. 2004 Absorbing Aerosol Index PMD image #12;biomass burning ocean

Graaf, Martin de

186

Cathode depth sensing in CZT detectors  

E-Print Network [OSTI]

Measuring the depth of interaction in thick Cadmium-Zinc-Telluride (CZT) detectors allows improved imaging and spectroscopy for hard X-ray imaging above 100 keV. The Energetic X-ray Imaging Survey Telescope (EXIST) will employ relatively thick (5 - 10 mm) CZT detectors, which are required to perform the broad energy-band sky survey. Interaction depth information is needed to correct events to the detector "focal plane" for correct imaging and can be used to improve the energy resolution of the detector at high energies by allowing event-based corrections for incomplete charge collection. Background rejection is also improved by allowing low energy events from the rear and sides of the detector to be rejected. We present experimental results of interaction depth sensing in a 5 mm thick pixellated Au-contact IMARAD CZT detector. The depth sensing was done by making simultaneous measurements of cathode and anode signals, where the interaction depth at a given energy is proportional to the ratio of cathode/anode signals. We demonstrate how a simple empirical formula describing the event distributions in the cathode/anode signal space can dramatically improve the energy resolution. We also estimate the energy and depth resolution of the detector as a function of the energy and the interaction depth. We also show a depth-sensing prototype system currently under development for EXIST in which cathode signals from 8, 16 or 32 crystals can be read-out by a small multi-channel ASIC board that is vertically edge-mounted on the cathode electrode along every second CZT crystal boundary. This allows CZT crystals to be tiled contiguously with minimum impact on throughput of incoming photons. The robust packaging is crucial in EXIST, which will employ very large area imaging CZT detector arrays.

J. Hong; E. C. Bellm; J. E. Grindlay; T. Narita

2003-10-16T23:59:59.000Z

187

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

E-Print Network [OSTI]

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

Tilstra, Gijsbert

188

E-Print Network 3.0 - aerosol chemical composition Sample Search...  

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

Aerosol on Clouds Summary: chemical composition and mixing stateTime-Resolved Aerosol Collector CCSEMEDX (ASP) Single particle... Sizer CCN spectrum Aerosol absorptionDRI...

189

E-Print Network 3.0 - aerosol number distributions Sample Search...  

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

inorganic composition PILS-IC Summary: 3563 nephelometers Aerosol number concentration CNC (TSI 3010, 3025) Aerosol size distribution DMA... and APS Non-volatile aerosol size...

190

Indirect and Semi-Direct Aerosol Campaign: The Impact of Arctic...  

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

Aerosol Campaign: The Impact of Arctic Aerosols on Clouds . Abstract: A comprehensive dataset of microphysical and radiative properties of aerosols and clouds in the arctic...

191

E-Print Network 3.0 - aerosol jet system Sample Search Results  

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

-controlled laminar aerosol jets and their application for studying aerosol combustion processes Author(s): Shoshin Y... 2002 Times Cited: 6 48. Title: Exhaust aerosol of a...

192

Capstone Depleted Uranium Aerosols: Generation and Characterization  

SciTech Connect (OSTI)

In a study designed to provide an improved scientific basis for assessing possible health effects from inhaling depleted uranium (DU) aerosols, a series of DU penetrators was fired at an Abrams tank and a Bradley fighting vehicle. A robust sampling system was designed to collect aerosols in this difficult environment and continuously monitor the sampler flow rates. Aerosols collected were analyzed for uranium concentration and particle size distribution as a function of time. They were also analyzed for uranium oxide phases, particle morphology, and dissolution in vitro. The resulting data provide input useful in human health risk assessments.

Parkhurst, MaryAnn; Szrom, Fran; Guilmette, Ray; Holmes, Tom; Cheng, Yung-Sung; Kenoyer, Judson L.; Collins, John W.; Sanderson, T. Ellory; Fliszar, Richard W.; Gold, Kenneth; Beckman, John C.; Long, Julie

2004-10-19T23:59:59.000Z

193

Simultaneous Retrieval of Effective Refractive Index and Density from Size Distribution and Light Scattering Data: Weakly-Absorbing Aerosol  

SciTech Connect (OSTI)

We propose here a novel approach for retrieving in parallel the effective density and real refractive index of weakly absorbing aerosol from optical and size distribution measurements. Here we define weakly absorbing as aerosol single-scattering albedos that exceed 0.95 at 0.5 um.The required optical measurements are the scattering coefficient and the hemispheric backscatter fraction, obtained in this work from an integrating nephelometer. The required size spectra come from a Scanning Mobility Particle Sizer and an Aerodynamic Particle Sizer. The performance of this approach is first evaluated using a sensitivity study with synthetically generated but measurement-related inputs. The sensitivity study reveals that the proposed approach is robust to random noise; additionally the uncertainties of the retrieval are almost linearly proportional to the measurement errors, and these uncertainties are smaller for the real refractive index than for the effective density. Next, actual measurements are used to evaluate our approach. These measurements include the optical, microphysical, and chemical properties of weakly absorbing aerosol which are representative of a variety of coastal summertime conditions observed during the Two-Column Aerosol Project (TCAP; http://campaign.arm.gov/tcap/). The evaluation includes calculating the root mean square error (RMSE) between the aerosol characteristics retrieved by our approach, and the same quantities calculated using the conventional volume mixing rule for chemical constituents. For dry conditions (defined in this work as relative humidity less than 55%) and sub-micron particles, a very good (RMSE~3%) and reasonable (RMSE~28%) agreement is obtained for the retrieved real refractive index (1.490.02) and effective density (1.680.21), respectively. Our approach permits discrimination between the retrieved aerosol characteristics of sub-micron and sub-10micron particles. The evaluation results also reveal that the retrieved density and refractive index tend to decrease with an increase of the relative humidity.

Kassianov, Evgueni I.; Barnard, James C.; Pekour, Mikhail S.; Berg, Larry K.; Shilling, John E.; Flynn, Connor J.; Mei, Fan; Jefferson, Anne

2014-10-01T23:59:59.000Z

194

Absolute Approximation of Tukey Depth: Theory and Experiments  

E-Print Network [OSTI]

Absolute Approximation of Tukey Depth: Theory and Experiments Dan Chen School of Computer Science¨ur Theoretische Informatik Abstract A Monte Carlo approximation algorithm for the Tukey depth problem in high. Keywords: Tukey depth, computational geometry 1. Introduction Tukey depth is also known as location depth

Morin, Pat

195

The Influence of Fog and Airmass History on Aerosol Optical,...  

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

spectrum to the pre-fog conditions immediately afterwards. Citation: Berkowitz CM, LK Berg, XY Yu, ML Alexander, A Laskin, RA Zaveri, BT Jobson, E Andrews, and JA Ogren.2011."The...

196

Incorporation of Aerosol Optical Properties into Climate Models  

E-Print Network [OSTI]

. Measured Annual Lightning Flash Rate Data from NASA LIS/OTD Science Team Model (4ox5o resolution) calculates lightning by accounting for size-resolved bounceoffs and charge separation in clouds. Results

197

Southern hemisphere tropospheric aerosol microphysics  

SciTech Connect (OSTI)

Aerosol particle size distribution data have been obtained in the southern hemisphere from approximately 4{degree}S to 44{degree}S and between ground level and 6 km, in the vicinity of eastern Australia. The relative shape of the free-tropospheric size distribution for particles with radii larger than approximately 0.04 {mu}m was found to be remarkably stable with time, altitude, and location for the autumn-winter periods considered. This was despite some large concentration changes which were found to be typical of the southeastern Australian coastal region. The majority of free-troposphere large particles were found to have sulfuric acid or lightly ammoniated sulfate morphology. Large particles in the boundary layer almost exclusively had a sea-salt morphology.

Gras, J.L. (Commonwealth Scientific and Industrial Research Organization, Aspendale (Australia))

1991-03-20T23:59:59.000Z

198

Composition and Reactions of Atmospheric Aerosol Particles  

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

Composition and Reactions of Composition and Reactions of Atmospheric Aerosol Particles Composition and Reactions of Atmospheric Aerosol Particles Print Wednesday, 29 June 2005 00:00 Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion emissions released from around the world. How long these tiny particles remain in the atmosphere can have a huge impact on the global climate. Measurements based 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 while changing organic composition by 13 to 24% per day, an oxidation rate significantly slower than is currently used in atmospheric models. Since oxidation has a strong effect on particle lifetime in the atmosphere, these results will help climate scientists refine the computer models used to predict climate change.

199

ARM - Measurement - Aerosol particle size distribution  

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

particle size distribution particle size distribution ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol particle size distribution The number of aerosol particles present in any given volume of air within a specificied size range Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments SMPS : Scanning mobility particle sizer TDMA : Tandem Differential Mobility Analyzer UHSAS : Ultra-High Sensitivity Aerosol Spectrometer Field Campaign Instruments

200

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 Composition and Reactions of Atmospheric Aerosol Particles Print Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion emissions released from around the world. How long these tiny particles remain in the atmosphere can have a huge impact on the global climate. Measurements based 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 while changing organic composition by 13 to 24% per day, an oxidation rate significantly slower than is currently used in atmospheric models. Since oxidation has a strong effect on particle lifetime in the atmosphere, these results will help climate scientists refine the computer models used to predict climate change.

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

NASA's Aerosol-Cloud-Ecosystems (ACE) Mission  

Science Journals Connector (OSTI)

Plans for NASAs Aerosol-Cloud-Ecosystem (ACE) mission is described. Recommended by Earth Science Decadal Survey in 2007, ACE is nominally planned for a 2021 launch. ACE is...

Starr, David O'C

202

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 Composition and Reactions of Atmospheric Aerosol Particles Print Microscopic aerosol particles in the atmosphere contain carbonaceous components from mineral dust and combustion emissions released from around the world. How long these tiny particles remain in the atmosphere can have a huge impact on the global climate. Measurements based 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 while changing organic composition by 13 to 24% per day, an oxidation rate significantly slower than is currently used in atmospheric models. Since oxidation has a strong effect on particle lifetime in the atmosphere, these results will help climate scientists refine the computer models used to predict climate change.

203

Stereoscopic optical viewing system  

DOE Patents [OSTI]

An improved optical system which provides the operator with a stereoscopic viewing field and depth of vision, particularly suitable for use in various machines such as electron or laser beam welding and drilling machines. The system features two separate but independently controlled optical viewing assemblies from the eyepiece to a spot directly above the working surface. Each optical assembly comprises a combination of eye pieces, turning prisms, telephoto lenses for providing magnification, achromatic imaging relay lenses and final stage pentagonal turning prisms. Adjustment for variations in distance from the turning prisms to the workpiece, necessitated by varying part sizes and configurations and by the operator's visual accuity, is provided separately for each optical assembly by means of separate manual controls at the operator console or within easy reach of the operator.

Tallman, C.S.

1986-05-02T23:59:59.000Z

204

ARM - Field Campaign - Aerosol Life Cycle IOP at BNL  

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

govCampaignsAerosol Life Cycle IOP at BNL govCampaignsAerosol Life Cycle IOP at BNL Campaign Links Images Wiki 2011 ASR STM Presentation: Sedlacek 2011 ASR STM Presentation: Springston 2010 ASR Fall Meeting: Sedlacek News, June 14, 2011: Next-generation Aerosol-sampling Stations to Head for India Related Campaigns Aerosol Life Cycle: Chemical Ionization Mass Spectrometer - CIMS 2011.07.10, Lee, OSC Aerosol Life Cycle: HR-ToF-AMS 2011.06.15, Zhang, OSC Aerosol Life Cycle: ARM Mobile Facility 2 Aerosol Observing System 2011.06.15, Sedlacek, OSC Aerosol Life Cycle: UV-APS and Nano-SMPS 2011.06.10, Hallar, OSC Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Aerosol Life Cycle IOP at BNL 2011.06.01 - 2011.08.31 Lead Scientist : Arthur Sedlacek For data sets, see below.

205

DETERMINATION OF RADIAL MOMENTS OF AN AEROSOL  

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

DETERMINATION OF RADIAL MOMENTS OF AN AEROSOL DETERMINATION OF RADIAL MOMENTS OF AN AEROSOL SIZE DISTRIBUTION FROM MEASUREMENTS OF LIGHT TRANSMITTANCE AND SCATTERING Ernie R. Lewis and Stephen E. Schwartz Brookhaven National Laboratory, Upton, NY 11933 ses@bnl.gov elewis@bnl.gov MOMENTS FROM MEASUREMENTS As each of the measured quantities is linear in the size distribution dn/dr, it is possible to construct linear combinations of measurements that yield

206

Aerosol fabrication methods for monodisperse nanoparticles  

DOE Patents [OSTI]

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.

Jiang, Xingmao; Brinker, C Jeffrey

2014-10-21T23:59:59.000Z

207

Electrically Driven Technologies for Radioactive Aerosol Abatement  

SciTech Connect (OSTI)

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.

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

2003-01-28T23:59:59.000Z

208

Development of plutonium aerosol fractionation system  

E-Print Network [OSTI]

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...

Mekala, Malla R.

1993-01-01T23:59:59.000Z

209

Atmospheric Aerosol Chemistry Analyzer: Demonstration of feasibility  

SciTech Connect (OSTI)

This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project objective was to demonstrate the technical feasibility of an Atmospheric Aerosol Chemistry Analyzer (AACA) that will provide a continuous, real-time analysis of the elemental (major, minor and trace) composition of atmospheric aerosols. The AACA concept is based on sampling the atmospheric aerosol through a wet cyclone scrubber that produces an aqueous suspension of the particles. This suspension can then be analyzed for elemental composition by ICP/MS or collected for subsequent analysis by other methods. The key technical challenge was to develop a wet cyclone aerosol sampler suitable for respirable particles found in ambient aerosols. We adapted an ultrasonic nebulizer to a conventional, commercially available, cyclone aerosol sampler and completed collection efficiency tests for the unit, which was shown to efficiently collect particles as small as 0.2 microns. We have completed the necessary basic research and have demonstrated the feasibility of the AACA concept.

Mroz, E.J.; Olivares, J.; Kok, G.

1996-04-01T23:59:59.000Z

210

E-Print Network 3.0 - aerosol microphysical characteristics Sample...  

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

new particle formation, aerosol microphysical evolution, three-dimensional transport, and wet... of aerosol microphysical properties. Some of ... Source: Brookhaven...

211

PublicationsmailagreementNo.40014024 maximum depth  

E-Print Network [OSTI]

and a video camera to complete installation of the world's first regional cabled ocean observatory. NEPTUNE- tion systems that--using power and the internet--provide continuous, long-term monitoring of oceanPublicationsmailagreementNo.40014024 THE 2.7km maximum depth beneath the ocean surface of neptune

Pedersen, Tom

212

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.

213

In-depth survey report of Roadway Express, Inc. , Toledo, Ohio  

SciTech Connect (OSTI)

An in-depth survey was conducted at Roadway Express, Inc., Toledo, Ohio to determine relative exposures to diesel aerosols among the four major presumably exposed job groups of road drivers, local drivers, dock workers, and mechanics. Element carbon sampling results at the Roadway terminal in Toledo, Ohio, during cold weather indicated low level exposures only slightly above geometric mean ambient residential and highway background concentrations in road drivers and local drivers. Exposures were significantly above background highway concentrations in dock workers and in mechanics, with exposures of 29 and 58 micrograms/cubic meter (microg/cu m), respectively. The highest levels of exposure were to mechanics working in the shop. Exposure to nitrogen oxides and respirable particulates were far below recommended limits. The major source of exposures in dock workers appeared to be the operation of diesel powered fork lift trucks on the dock. The principal source in mechanics was the entry and egress of diesel tractors to and from the shop area, but the more enclosed environment in which they were working exacerbated concentrations of diesel aerosols.

Zaebst, D.D.; Ringenburg, V.; Sanderson, W.

1989-09-09T23:59:59.000Z

214

Optical Fibers Optics and Photonics  

E-Print Network [OSTI]

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

Palffy-Muhoray, Peter

215

The near future availability of photovoltaic energy in Europe and Africa in climate-aerosol modeling experiments  

Science Journals Connector (OSTI)

Abstract The near future change in productivity of photovoltaic energy (PVE) in Europe and Africa is assessed by using the climate variables simulated by the ECHAM5-HAM aerosol-climate model, and a model for the performance of photovoltaic systems. The climate simulations are forced by green-house gases emissions from the IPCC SRES B2 scenario. In addition, different scenarios for future anthropogenic aerosols emissions are applied. Thus, the sensitivity of the future PVE productivity to changes in aerosol atmospheric burdens between 2000 and 2030 is analyzed. The analysis indicates that reductions in aerosols emissions in the near future result in an increase of global warming, and a significant response in surface solar radiation and associated PVE productivity. A statistically significant reduction in PVE productivity up to 7% is observed in eastern Europe and northern Africa, while a significant increase up to 10% is observed in western Europe and eastern Mediterranean. The changes in surface solar radiation and PVE productivity are related to global effects of aerosols reduction on the large scale circulation and associated cloud cover pattern, rather than to local effects on the atmospheric optical properties. PVE assessment is then discussed in the frame of the present situation and next decades evolution of the photovoltaic market, highlighting that the effects on productivity induced by industrial and public policies, and technological development are comparable to climate related effects. The presented results encourage the improvement and further use of climate models in assessment of future renewable energies availability.

Marco Gaetani; Thomas Huld; Elisabetta Vignati; Fabio Monforti-Ferrario; Alessandro Dosio; Frank Raes

2014-01-01T23:59:59.000Z

216

DOE research on atmospheric aerosols  

SciTech Connect (OSTI)

Atmospheric aerosols are the subject of a significant component of research within DOE`s environmental research activities, mainly under two programs within the Department`s Environmental Sciences Division, the Atmospheric Radiation Measurement (ARM) Program and the Atmospheric Chemistry Program (ACP). Research activities conducted under these programs include laboratory experiments, field measurements, and theoretical and modeling studies. The objectives and scope of these programs are briefly summarized. The ARM Program is the Department`s major research activity focusing on atmospheric processes pertinent to understanding global climate and developing the capability of predicting global climate change in response to energy related activities. The ARM approach consists mainly of testing and improving models using long-term measurements of atmospheric radiation and controlling variables at highly instrumented sites in north central Oklahoma, in the Tropical Western Pacific, and on the North Slope of Alaska. Atmospheric chemistry research within DOE addresses primarily the issue of atmospheric response to emissions from energy-generation sources. As such this program deals with the broad topic known commonly as the atmospheric source-receptor sequence. This sequence consists of all aspects of energy-related pollutants from the time they are emitted from their sources to the time they are redeposited at the Earth`s surface.

Schwartz, S.E.

1995-11-01T23:59:59.000Z

217

ARM - Field Campaign - Carbonaceous Aerosol and Radiative Effects Study  

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

govCampaignsCarbonaceous Aerosol and Radiative Effects Study (CARES) govCampaignsCarbonaceous Aerosol and Radiative Effects Study (CARES) Campaign Links CARES Website Related Campaigns Carbonaceous Aerosol and Radiation Effects Study (CARES) - Surface Meteorological Sounding 2010.05.26, Zaveri, OSC Carbonaceous Aerosol and Radiation Effects Study (CARES) Photo-Acoustic Aerosol Light Absorption and Scattering 2010.05.26, Arnott, OSC Carbonaceous Aerosol and Radiative Effects Study (CARES): SMPS & CCN counter deployment during CARES/Cal-NEx 2010.05.04, Wang, OSC Carbonaceous Aerosol and Radiative Effects Study (CARES) Ground Based Instruments 2010.04.01, Cziczo, OSC Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Carbonaceous Aerosol and Radiative Effects Study (CARES)

218

Distinguishing Aerosol Impacts on Climate over the Past Century  

Science Journals Connector (OSTI)

Aerosol direct (DE), indirect (IE), and black carbonsnow albedo (BAE) effects on climate between 1890 and 1995 are compared using equilibrium aerosolclimate simulations in the Goddard Institute for Space Studies General Circulation Model ...

Dorothy Koch; Surabi Menon; Anthony Del Genio; Reto Ruedy; Igor Alienov; Gavin A. Schmidt

2009-05-01T23:59:59.000Z

219

Fast neutron background measurements at shallow depths  

SciTech Connect (OSTI)

We report on measurements of the neutron backgrounds for neutrino experiments at shallow depth (such as the proposed San Onofre neutrino oscillation experiment). A detector capable of pulse-shape discrimination measured the flux of fast neutrons at 20 mwe depth in the Stanford Underground Facility to be (1.07 {+-} 0.30) X 10{sup -6} cm{sup -2} s{sup -1}. An experiment, situated in the Tendon Gallery of the San Onofre Unit 2 reactor. studied spallation neutrons from muons traversing Pb and Cu. An underground experiment in the SUF, employing a detector filled with Gd-loaded liquid scintillator, is measuring the neutron production rate and multiplicity for muon spallation in low-A material (hydrocarbon-based liquid scintillator).

Chen, M.; Hertenberger, R.; Novikov, V. [Inst. of Nuclear Research, Moscow (Russian Federation); Dougherty, B.

1993-10-01T23:59:59.000Z

220

Property:Depth(m) | Open Energy Information  

Open Energy Info (EERE)

Depth(m) Depth(m) Jump to: navigation, search This is a property of type String. Pages using the property "Depth(m)" Showing 25 pages using this property. (previous 25) (next 25) 1 1.5-ft Wave Flume Facility + 0.9 + 10-ft Wave Flume Facility + 1.5 + 11-ft Wave Flume Facility + 1.8 + 2 2-ft Flume Facility + 1.8 + 3 3-ft Wave Flume Facility + 0.9 + 5 5-ft Wave Flume Facility + 1.5 + 6 6-ft Wave Flume Facility + 1.8 + A Alden Large Flume + 3.0 + Alden Small Flume + 1.8 + Alden Tow Tank + 1.2 + Alden Wave Basin + 1.2 + B Breakwater Research Facility + 0.8 + Bucknell Hydraulic Flume + 0.6 + C Carderock 2-ft Variable Pressure Cavitation Water Tunnel + 0.6 + Carderock 3-ft Variable Pressure Cavitation Water Tunnel + 0.7 + Carderock Circulating Water Channel + 2.7 +

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Emission-Induced Nonlinearities in the Global Aerosol System: Results from the ECHAM5-HAM Aerosol-Climate Model  

Science Journals Connector (OSTI)

In a series of simulations with the global ECHAM5-HAM aerosol-climate model, the response to changes in anthropogenic emissions is analyzed. Traditionally, additivity is assumed in the assessment of the aerosol climate impact, as the underlying ...

Philip Stier; Johann Feichter; Silvia Kloster; Elisabetta Vignati; Julian Wilson

2006-08-01T23:59:59.000Z

222

Toward a Minimal Representation of Aerosols in Climate Models: Comparative Decomposition of Aerosol Direct, Semidirect, and Indirect Radiative Forcing  

Science Journals Connector (OSTI)

The authors have decomposed the anthropogenic aerosol radiative forcing into direct contributions from each aerosol species to the planetary energy balance through absorption and scattering of solar radiation, indirect effects of anthropogenic ...

S. J. Ghan; X. Liu; R. C. Easter; R. Zaveri; P. J. Rasch; J.-H. Yoon; B. Eaton

2012-10-01T23:59:59.000Z

223

Nonequilibrium atmospheric secondary organic aerosol formation and growth  

Science Journals Connector (OSTI)

...Mexico City area are shown...inorganic atmospheric aerosols...2005 ) A large organic aerosol source...photochemical and thermal studies of...Characteristic Group FrequenciesTables and...particle thermal speed...phase-equilibrium in the atmospheric system: Aerosol...Support, Non-U.S...Determination by plasma-based...implications for atmospheric chemistry...2002) A thermal disso-ciation...

Vronique Perraud; Emily A. Bruns; Michael J. Ezell; Stanley N. Johnson; Yong Yu; M. Lizabeth Alexander; Alla Zelenyuk; Dan Imre; Wayne L. Chang; Donald Dabdub; James F. Pankow; Barbara J. Finlayson-Pitts

2012-01-01T23:59:59.000Z

224

Organic and Inorganic Aerosol Below-Cloud Scavenging by  

E-Print Network [OSTI]

concentrations, with an average gravimetric PM1.0 of 8.2 ( 1.6 µg m-3 and an average Fourier transform infrared-rinsing behavior was unaffected by source type. The aerosol OM was hydrophilic throughout the sampling period the description of aerosol lifetimes in global models. Introduction Wet and dry deposition of aerosol particles

Russell, Lynn

225

DO AEROSOLS CHANGE CLOUD COVER AND AFFECT CLIMATE?  

E-Print Network [OSTI]

AS SEEN FROM SPACE Fire plumes from southern Mexico transported north into Gulf of Mexico. #12;CLOUD IPCC AR4 (2007) 3210-1-2 Forcing, W m-2 CO2 CH4 CFCs N2O Long Lived Greenhouse Gases Tropospheric;AEROSOL INFLUENCES ON CLIMATE AND CLIMATE CHANGE #12;DMS #12;AEROSOL IN MEXICO CITY BASIN #12;AEROSOL

Schwartz, Stephen E.

226

Tomographic image reconstruction from optical projections in light-diffusing media  

Science Journals Connector (OSTI)

The recent developments in light generation and detection techniques have opened new possibilities for optical medical imaging, tomography, and diagnosis at tissue penetration depths...

Colak, S B; Papaioannou, D G; t Hooft, G W; van der Mark, M B; Schomberg, H; Paasschens, J C J; Melissen, J B M; van Asten, N A A J

1997-01-01T23:59:59.000Z

227

Indirect and Semi-Direct Aerosol Campaign  

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

Campaign Campaign For the month of April, researchers are descending on and above Barrow, Alaska, to obtain data from the atmosphere that will help them understand the impacts that aerosols have on Arctic clouds and climate. Scientists sponsored by the U.S. Department of Energy's Atmospheric Radiation Measurement (ARM) Climate Research Facility are using a heavily instrumented aircraft to collect data from the sky, while instruments based at surface sites in Barrow and Atqasuk, Alaska, are obtaining measurements from the ground. Information obtained during the Indirect and Semi-Direct Aerosol Campaign, or ISDAC, will help scientists analyze the role of aerosols in climate, and represents a key contribution to Arctic climate research during International Polar Year.

228

Researchers Model Impact of Aerosols Over California  

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

Researchers Model Researchers Model Impact of Aerosols Over California Researchers Model Impact of Aerosols Over California Research may clarify the effectiveness of regional pollution controls May 28, 2013 | Tags: Climate Research, Hopper Contact: Linda Vu, lvu@lbl.gov, (510) 495-2404 LosAngelesSmogv1.jpg Smog over downtown Los Angeles. Aerosols are microscopic particles-like dust, pollen and soot-that ubiquitously float around in our atmosphere. Despite their tiny stature, these particles can have a huge impact on human health, climate and the environment. So scientists from the Pacific Northwest National Laboratory (PNNL), Colorado State University and the California Air Resources Board have set out to characterize the roles of various particles as atmospheric change agents on a regional scale.

229

Characterizing the formation of secondary organic aerosols  

SciTech Connect (OSTI)

Organic aerosol is an important fraction of the fine particulate matter present in the atmosphere. This organic aerosol comes from a variety of sources; primary organic aerosol emitted directly from combustion process, and secondary aerosol formed in the atmosphere from condensable vapors. This secondary organic aerosol (SOA) can result from both anthropogenic and biogenic sources. In rural areas of the United States, organic aerosols can be a significant part of the aerosol load in the atmosphere. However, the extent to which gas-phase biogenic emissions contribute to this organic load is poorly understood. Such an understanding is crucial to properly apportion the effect of anthropogenic emissions in these rural areas that are sometimes dominated by biogenic sources. To help gain insight on the effect of biogenic emissions on particle concentrations in rural areas, we have been conducting a field measurement program at the University of California Blodgett Forest Research Facility. The field location includes has been used to acquire an extensive suite of measurements resulting in a rich data set, containing a combination of aerosol, organic, and nitrogenous species concentration and meteorological data with a long time record. The field location was established in 1997 by Allen Goldstein, a professor in the Department of Environmental Science, Policy and Management at the University of California at Berkeley to study interactions between the biosphere and the atmosphere. The Goldstein group focuses on measurements of concentrations and whole ecosystem biosphere-atmosphere fluxes for volatile organic compounds (VOC's), oxygenated volatile organic compounds (OVOC's), ozone, carbon dioxide, water vapor, and energy. Another important collaborator at the Blodgett field location is Ronald Cohen, a professor in the Chemistry Department at the University of California at Berkeley. At the Blodgett field location, his group his group performs measurements of the concentrations of important gas phase nitrogen compounds. Experiments have been ongoing at the Blodgett field site since the fall of 2000, and have included portions of the summer and fall of 2001, 2002, and 2003. Analysis of both the gas and particle phase data from the year 2000 show that the particle loading at the site correlates with both biogenic precursors emitted in the forest and anthropogenic precursors advected to the site from Sacramento and the Central Valley of California. Thus the particles at the site are affected by biogenic processing of anthropogenic emissions. Size distribution measurements show that the aerosol at the site has a geometric median diameter of approximately 100 nm. On many days, in the early afternoon, growth of nuclei mode particles (<20 nm) is also observed. These growth events tend to occur on days with lower average temperatures, but are observed throughout the summer. Analysis of the size resolved data for these growth events, combined with typical measured terpene emissions, show that the particle mass measured in these nuclei mode particles could come from oxidation products of biogenic emissions, and can serve as a significant route for SOA partitioning into the particle phase. During periods of each year, the effect of emissions for forest fires can be detected at the Blodgett field location. During the summer of 2002 emissions from the Biscuit fire, a large fire located in Southwest Oregon, was detected in the aerosol data. The results show that increases in particle scattering can be directly related to increased black carbon concentration and an appearance of a larger mode in the aerosol size distribution. These results show that emissions from fires can have significant impact on visibility over large distances. The results also reinforce the view that forest fires can be a significant source of black carbon in the atmosphere, which has important climate and visibility. Continuing work with the 2002 data set, particularly the combination of the aerosol and gas phase data, will continue to provide important information o

Lunden, Melissa; Black, Douglas; Brown, Nancy

2004-02-01T23:59:59.000Z

230

Aerodynamic Focusing Of High-Density Aerosols  

SciTech Connect (OSTI)

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.

Ruiz, D. E.; Fisch, Nathaniel

2014-02-24T23:59:59.000Z

231

The effect of Immersion oil in optical tweezers  

E-Print Network [OSTI]

In this paper, we report on theoretical investigation of the effect of refractive index of immersion oil on the position of optimal depth and optical trap quality in optical tweezers. Using simple numerical calculation presented here, one can study the optical trapping in different samples, after multi interfaces and find the best choice of immersion oil for a particular case.

Mahmoudi, Ali

2010-01-01T23:59:59.000Z

232

Reflective 'cool' roofs under aerosol-burdened skies: radiative benefits across selected Indian cities  

Science Journals Connector (OSTI)

The use of reflective surfaces offers one low-cost solution for reducing solar loading to urban environments and the Earth that should be considered as part of sustainable urban design. Here, we characterize the radiative benefits, i.e. the additional shortwave radiation leaving the atmosphere, from the installation of highly reflective 'cool' roofs in urban areas in India that face relatively large local aerosol burdens. We use a previously tested column radiative transfer model to estimate the energy per unit area reflected to space from increasing the surface albedo at six cities within India. The model is used to characterize radiative transfer each day over five years (20082012) based on mid-day satellite retrievals of MODIS aerosol depth, cloud water path, and average surface albedo and MERRA atmospheric profiles of temperature and composition. Compared against ten months of field observations in two cities, the model derived incoming surface shortwave radiation estimates relative to observations show small biases (0.5% and ?2.6%, at Pantnagar and Nainital, respectively). Despite the high levels of local aerosols we found cool roofs provided significant radiative benefits at all locations. Averaged over the five year period we found that increasing the albedo of 1 m2 of roof area by 0.5 would reflect to space 0.91.2 kWh daily from 08:3015:30 LST, depending on location. This is equivalent to a constant forcing of 3750 W m?2 (equivalent to reducing CO2 emissions by 74 to 101 kg CO2 m?2 roof area). Last, we identify a co-benefit of improving air quality, in that removing aerosols from the atmosphere could increase the radiative benefits from cool roofs by 2374%, with the largest potential increase found at Delhi and the smallest change found at Nainital.

D E Millstein; M L Fischer

2014-01-01T23:59:59.000Z

233

Near real time vapor detection and enhancement using aerosol adsorption  

SciTech Connect (OSTI)

A vapor sample detection method 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.

Novick, Vincent J.; Johnson, Stanley A.

1997-12-01T23:59:59.000Z

234

Technical Note: Estimating Aerosol Effects on Cloud Radiative Forcing  

SciTech Connect (OSTI)

Estimating anthropogenic aerosol effects on the planetary energy balance through the aerosol influence on clouds using the difference in cloud radiative forcing from simulations with and without anthropogenic emissions produces estimates that are positively biased. A more representative method is suggested using the difference in cloud radiative forcing calculated with aerosol radiative effects neglected. The method also yields an aerosol radiative forcing decomposition that includes a term quantifying the impact of changes in surface albedo. The method requires only two additional diagnostic calculations: the whole-sky and clear-sky top-of-atmosphere radiative flux with aerosol radiative effects neglected.

Ghan, Steven J.

2013-10-09T23:59:59.000Z

235

Near real time vapor detection and enhancement using aerosol adsorption  

DOE Patents [OSTI]

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.

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

1999-08-03T23:59:59.000Z

236

Near real time vapor detection and enhancement using aerosol adsorption  

DOE Patents [OSTI]

A vapor sample detection method 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.

Novick, Vincent J. (Downers Grove, IL); Johnson, Stanley A. (Countryside, IL)

1999-01-01T23:59:59.000Z

237

Aerosol Science and Technology, 41:202216, 2007 Copyright c American Association for Aerosol Research  

E-Print Network [OSTI]

processes, such as con- densation, coagulation, gas-to-particle conversion (Reid et al. 1998), and particle Aerosol size distribution is, along with particle refractive in- dex and shape, one of important

238

A balloon-borne aerosol spectrometer for high altitude low aerosol concentration measurements  

SciTech Connect (OSTI)

Funded by Air Force Wright Aeronautical Laboratory, a new balloon-borne high altitude aerosol spectrometer, for the measurement of cirrus cloud ice crystals, has been developed and successfully flown by Sandia National Laboratories and Radiance Research. This report (1) details the aerosol spectrometer design and construction, (2) discusses data transmission and decoding, (3) presents data collected on three Florida flights in tables and plots. 2 refs., 11 figs., 3 tabs.

Brown, G.S. (Sandia National Labs., Albuquerque, NM (USA)); Weiss, R.E. (Radiance Research, Seattle, WA (USA))

1990-08-01T23:59:59.000Z

239

Understanding Brown Carbon Aerosols and Their Role in Climate Change  

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

Brown Carbon Aerosols Brown Carbon Aerosols Tiny aerosol particles in the atmosphere are a possible cause of climate change. Among the many contributors to climate change are aerosols in the atmosphere. These tiny particles suspended in the air come from many sources, some natural and some man-made. Some aerosols are organic (containing carbon), while others are inorganic (such as sea salt and sulfates). Most aerosols reflect sunlight, and some also absorb it. Many of these nanoparticles have severe health effects in addition to climate effects. Human activities that produce aerosols include transportation, industry, and agriculture. Black carbon particles (a component of soot) originating from combustion processes have been known for some time to absorb sunlight and warm the

240

Response of California temperature to regional anthropogenic aerosol  

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

Response of California temperature to regional anthropogenic aerosol Response of California temperature to regional anthropogenic aerosol changes Title Response of California temperature to regional anthropogenic aerosol changes Publication Type Journal Article Year of Publication 2008 Authors Novakov, Tihomir, Thomas W. Kirchstetter, Surabi Menon, and Jeffery Aguiar Journal Geophysical Research Letters Volume 35 Issue 19 Abstract In this paper, we compare constructed records of concentrations of black carbon (BC) - an indicator of anthropogenic aerosols - with observed surface temperature trends in California. Annual average BC concentrations in major air basins in California significantly decreased after about 1990, coincident with an observed statewide surface temperature increase. Seasonal aerosol concentration trends are consistent with observed seasonal temperature trends. These data suggest that the reduction in anthropogenic aerosol concentrations contributed to the observed surface temperature increase. Conversely, high aerosol concentrations may lower surface temperature and partially offset the temperature increase of greenhouse gases.

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

The Aerosol Modeling Testbed: A community tool to objectively evaluate aerosol process modules  

SciTech Connect (OSTI)

This study describes a new modeling paradigm that significantly advances how the third activity is conducted while also fully exploiting data and findings from the first two activities. The Aerosol Modeling Testbed (AMT) is a computational framework for the atmospheric sciences community that streamlines the process of testing and evaluating aerosol process modules over a wide range of spatial and temporal scales. The AMT consists of a fully-coupled meteorology-chemistry-aerosol model, and a suite of tools to evaluate the performance of aerosol process modules via comparison with a wide range of field measurements. The philosophy of the AMT is to systematically and objectively evaluate aerosol process modules over local to regional spatial scales that are compatible with most field campaigns measurement strategies. The performance of new treatments can then be quantified and compared to existing treatments before they are incorporated into regional and global climate models. Since the AMT is a community tool, it also provides a means of enhancing collaboration and coordination among aerosol modelers.

Fast, Jerome D.; Gustafson, William I.; Chapman, Elaine G.; Easter, Richard C.; Rishel, Jeremy P.; Zaveri, Rahul A.; Grell, Georg; Barth, Mary

2011-03-02T23:59:59.000Z

242

Source Apportionment of Carbonaceous Aerosols using  

E-Print Network [OSTI]

are different than the collection of particles from water Filtration has high efficiency for all sizes Size Condensation Nuclei (CCN) Human health Carbonaceous aerosol implicated as important for toxicity and adverse of particulate matter Again, agreement between these two approaches would give a high level of confidence

Einat, Aharonov

243

Photophoretic levitation of engineered aerosols for geoengineering  

Science Journals Connector (OSTI)

...W. Keith Energy and Environmental...space-based solar scattering...The salient advantage of sulfate aerosols...instrument. Disadvantages of sulfates...concentrating solar power systems...higher energy than molecules...solving the energy balance equation...ratio of solar-spectrum to thermal-spectrum...two of the disadvantages of stratospheric...

David W. Keith

2010-01-01T23:59:59.000Z

244

Modeling Semivolatile Organic Aerosol Mass Emissions from  

E-Print Network [OSTI]

in diluted diesel and wood combustion exhaust are interpreted using a two-component absorptive with dilution of both wood smoke and diesel exhaust can be described by two lumped compounds in roughly equal. Introduction Sources of organic aerosol such as diesel engines and wood stoves emit semivolatile organic

Stanier, Charlie

245

ADEPT. aerosol deposition in cylindrical pipes  

SciTech Connect (OSTI)

ADEPT calculates the deposition of aerosols in straight cylindrical pipes during turbulent air flow. Aerosol deposition is calculated in a time-dependent manner based on empirical correlations for turbulent flow in pipes. The calculated deposition during a single time interval is cumulative with that of previous time intervals and results in a decreasing inner diameter of the pipe. The calculated deposition is assumed uniform over the length of the pipe. The entering aerosol distribution is specified by the user in the form of a log-normal distribution of accumulated mass versus particle size and may be time dependent. Entering flow conditions are also specified by the user and may also be time dependent. For simplicity and generality, the geometry implicit in the program is that of a cylindrical pipe with no bends or fittings. The flow is turbulent and monodirectional; only one set of inlet conditions may be applied at a given time. The flow parameters are not calculated along the length of pipe; therefore, the dynamic behavior of the aerosol within the pipe as well as the effects of reentrainment cannot be determined explicitly. A typical problem requires 2 minutes of CPU time.

Fazekas, P.; Tewarson, S.C (Burns and Roe, Oradell, NJ (United States))

1985-01-01T23:59:59.000Z

246

ADEPT. Aerosol Deposition in Cylindrical Pipes  

SciTech Connect (OSTI)

ADEPT calculates the deposition of aerosols in straight cylindrical pipes during turbulent air flow. Aerosol deposition is calculated in a time-dependent manner based on empirical correlations for turbulent flow in pipes. The calculated deposition during a single time interval is cumulative with that of previous time intervals and results in a decreasing inner diameter of the pipe. The calculated deposition is assumed uniform over the length of the pipe. The entering aerosol distribution is specified by the user in the form of a log-normal distribution of accumulated mass versus particle size and may be time dependent. Entering flow conditions are also specified by the user and may also be time dependent. For simplicity and generality, the geometry implicit in the program is that of a cylindrical pipe with no bends or fittings. The flow is turbulent and monodirectional; only one set of inlet conditions may be applied at a given time. The flow parameters are not calculated along the length of pipe; therefore, the dynamic behavior of the aerosol within the pipe as well as the effects of reentrainment cannot be determined explicitly. A typical problem requires 2 minutes of CPU time.

Fazekas, P.; Tewarson, S.C [Burns and Roe, Oradell, NJ (United States)

1985-01-01T23:59:59.000Z

247

3, 59195976, 2003 The nitrate aerosol  

E-Print Network [OSTI]

ACPD 3, 5919­5976, 2003 The nitrate aerosol field over Europe M. Schaap et al. Title Page Abstract of Utrecht, Institute of Marine and Atmospheric Science, PO Box 80005, 3508 TA, Utrecht, The Netherlands 2, The Netherlands 3 Netherlands Energy Research Foundation (ECN), PO Box 1, 1755 LE Petten, The Netherlands 4 Joint

Paris-Sud XI, Université de

248

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

E-Print Network [OSTI]

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

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

2012-01-01T23:59:59.000Z

249

ARM - Publications: Science Team Meeting Documents  

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

3) Characterize the measurements in terms of other parameters derived from other sensors (e. g., column water content, aerosol optical depth). 4) Promote the development...

250

UNDERSTANDING THE INFLUENCES OF ATMOSPHERIC AEROSOLS ON CLIMATE AND CLIMATE CHANGE  

E-Print Network [OSTI]

.ecd.bnl.gov/steve BOB BRAWDY / AP #12;OVERVIEW Aerosol influences on climate and climate change Earth's energy balance 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

Schwartz, Stephen E.

251

Depth profiling ambient noise in the deep ocean  

E-Print Network [OSTI]

al. , 2005). The vertical profile of wind speed over the seavertical directionality Depth-dependence of wind speedVertical noise directional density function versus depth. 93 Measured and acoustically estimated wind speeds.

Barclay, David Readshaw

2011-01-01T23:59:59.000Z

252

OPTICS5  

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

Optics5 (5.1.02) Knowledge Base Optics5 (5.1.02) Knowledge Base Last Updated: 09/11/13 Table of Contents INSTALLATION EXECUTION bullet ** Operating Systems -- Microsoft Windows 7 and Vista ** bullet ** Running Optics5 with Microsoft Windows 7 and Vista ** bullet ** Running Optics5 with Microsoft Windows 7 and Vista 64 bit ** Optics5 may not work correctly with regional/locale settings using "," as a decimal separator. bullet Which Windows operating systems can be used to run Optics? "Class Does Not Support Automation or Expected Interface" error message bullet How much hard disk space should be available to install Optics? Optics user manual bullet I receive a virus warning (nimda-virus) when installing Optics. What should I do? NFRC Procedure for Applied Films bullet I have installed Optics but I can't find the program or the icon.

253

Output-Sensitive Algorithms for Tukey Depth and Related Problems  

E-Print Network [OSTI]

Output-Sensitive Algorithms for Tukey Depth and Related Problems David Bremner University of New de Bruxelles Pat Morin Carleton University Abstract The Tukey depth (Tukey 1975) of a point p halfspace that contains p. Algorithms for computing the Tukey depth of a point in various dimensions

Morin, Pat

254

Composition analyses of size-resolved aerosol samples taken from aircraft downwind of Kuwait, Spring 1991  

SciTech Connect (OSTI)

Analyses are reported for eight aerosol samples taken from the National Center for Atmospheric Research Electra typically 200 to 250 km downwind of Kuwait between May 19 and June 1, 1991. Aerosols were separated into fine (D{sub p} < 2.5 {mu}m) and coarse (2.5 < D{sub p} 10 {mu}m) particles for optical, gravimetric, X ray and nuclear analyses, yielding information on the morphology, mass, and composition of aerosols downwind of Kuwait. The mass of coarse aerosols ranged between 60 and 1971 {mu}g/m{sup 3} and, while dominated by soil derived aerosols, contained considerable content of sulfates and salt (NaCl) and soot in the form of fluffy agglomerates. The mass of fine aerosols varied between 70 and 785 {mu}g/m{sup 3}, of which about 70% was accounted for via compositional analyses performed in vacuum. While most components varied greatly from flight to flight, organic matter and fine soils each accounted for about 1/4 of the fine mass, while salt and sulfates contributed about 10% and 7%, respectively. The Cl/S ratios were remarkably constant, 2.4 {+-} 1.2 for coarse particles and 2.0 {+-} 0.2 for fine particles, with one flight deleted in each case. Vanadium, when observed, ranged from 9 to 27 ng/m{sup 3}, while nickel ranged from 5 to 25 ng/m{sup 3}. In fact, fine sulfates, vanadium, and nickel occurred in levels typical of Los Angeles, California, during summer 1986. The V/Ni ratio, 1.7 {+-} 0.4, was very similar to the ratios measured in fine particles from combusted Kuwaiti oil, 1.4 {+-} 0.9. Bromine, copper, zinc, and arsenic/lead were also observed at levels between 2 and 190 ng/m{sup 3}. The presence of massive amounts of fine, typically alkaline soils in the Kuwaiti smoke plumes significantly modified their behavior and probably mitigated their impacts, locally and globally. 16 refs., 1 fig., 3 tabs.

Cahill, T.A.; Wilkinson, K. [Univ. of California, Davis, CA (United States); Schnell, R. [National Center for Atmospheric Research, Boulder, CO (United States)

1992-09-20T23:59:59.000Z

255

ARM - Field Campaign - Biogenic Aerosols - Effects on Clouds and Climate:  

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

govCampaignsBiogenic Aerosols - Effects on Clouds and Climate: govCampaignsBiogenic Aerosols - Effects on Clouds and Climate: FIGAERO-ToF-CIMS Instrument in Hyytiala with AMF-2 Related Campaigns Biogenic Aerosols- Effects on Clouds and Climate 2014.02.01, Petäjä, AMF Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Biogenic Aerosols - Effects on Clouds and Climate: FIGAERO-ToF-CIMS Instrument in Hyytiala with AMF-2 2014.04.01 - 2014.06.01 Lead Scientist : Joel Thornton Description The ultimate goal of this work is to connect field and laboratory observations of organic aerosol chemical and physical properties during the nascent growth stage to the diurnal and vertical distributions of aerosol abundance measured over the boreal forest by the ARM Mobile Facility 2

256

Aerosol Modeling at LLNL - Our capability, results, and perspective  

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

Aerosol Indirect Effects to Cloud Aerosol Indirect Effects to Cloud Parameterizations in Short-Range Weather Forecasts with CAM3 Over the Southern Great Plains during May 2003 IOP Lawrence Livermore National Laboratory This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 Catherine Chuang, James Boyle Shaocheng Xie and James Kelly LLNL-POST-401948 March 11, 2008 Why are aerosol/cloud interactions important? The greatest uncertainty in the assessment of radiative forcing arises from the interactions of aerosols with clouds. Radiative forcing of climate between 1750 and 2005 (IPCC, 2007) Sources of uncertainty Emissions Gas to particle conversion Aerosol size distribution Linkage between aerosols

257

Retrieval of ozone and nitrogen dioxide concentrations from Stratospheric Aerosol and Gas Experiment III (SAGE III)  

E-Print Network [OSTI]

Retrieval of ozone and nitrogen dioxide concentrations from Stratospheric Aerosol and Gas extinction. We retrieve ozone and nitrogen dioxide number densities and aerosol extinction from transmission), Retrieval of ozone and nitrogen dioxide concentrations from Stratospheric Aerosol and Gas Experiment III

258

Aerosol climate effects and air quality impacts from 1980 to 2030  

E-Print Network [OSTI]

Aerosol climate e?ects and air quality impacts from 1980 toAerosol climate e?ects and air quality impacts from 1980 toAerosol climate e?ects and air quality impacts from 1980 to

Menon, Surabi

2008-01-01T23:59:59.000Z

259

Statistical analysis of aerosol species, trace gasses, and meteorology in Chicago  

E-Print Network [OSTI]

possible pollutant sources. Keywords Atmospheric aerosols . Canonical correlation analysis . Chicago air pollution studies involve collection and anal- ysis of atmospheric aerosols and concurrent meteorol- ogy) and principal component analysis (PCA) were applied to atmospheric aerosol and trace gas concentrations

O'Brien, Timothy E.

260

Depth dependence of ambient noise in the northeastern Pacific Ocean  

Science Journals Connector (OSTI)

Omnidirectional ambient noise levels were measured at two deep?water locations in the northeastern Pacific Ocean.Hydrophones were positioned throughout the water column at depths ranging from about 200 m below the surface to about 150 m above the sea bottom. Analyses of the data over the frequencies from 15 to 800 Hz show that at low frequencies the noise levels decrease with increasing depth. The decrease with depth is greater below the critical depth than it is in the sound channel. These low?frequency noise levels and their depth dependence are independent of the wind speed. At higher frequencies the noise levels and the depth dependence are controlled by the wind?generated noise. At low wind speeds there is a decrease in levels below the critical depth but above this depth both increases and decreases in levels with depth were noted. At these high frequencies during high wind speeds the noise levels not only rise but also fill the water column to the extent that there is little decrease in level with increasing depth even for the region below the critical depth.

Gerald B. Morris

1978-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

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

SciTech Connect (OSTI)

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.

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.

2012-02-17T23:59:59.000Z

262

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

SciTech Connect (OSTI)

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.

Fast J. D.; Springston S.; GustafsonJr., 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.

2012-02-17T23:59:59.000Z

263

Priorities for In-situ Aerosol Measurements  

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

Priorities for In-situ Priorities for In-situ Aerosol Measurements Parameters * Aerosol light absorption coefficient - spectral, including UV, vis, and IR - as f(RH), and at ambient RH * Phase function - or relevant integral properties (how many?) * Ice nuclei * Scattering vs. RH, for RH>90% * CCN, as f(S, D p ) * Size distribution * Chemical composition - for determining climate forcing, vs. radiative effect Calibration * Number concentration * Size and shape * Light absorption reference method Characterization * Accuracy and precision - need well-understood error bars * Algorithm comparisons * Closure studies * Facilities for method testing - aircraft time Methods * Inlets - shattering/splashing - location on airplane - passing efficiency - inletless analyzers/samplers * Packaging - modular/portable "pods" for multiple a/c

264

Aerosol and graphitic carbon content of snow  

SciTech Connect (OSTI)

Snow samples from southern New Mexico, west Texas, Antarctica, and Greenland were analyzed for aerosol and graphitic carbon. Graphitic carbon contents were found to be between 2.2 and 25 ..mu..g L/sup -1/ of snow meltwater; water-insoluble aerosol content varied between 0.62 and 8.5 mg L/sup -1/. For comparison, two samples of Camp Century, Greenland, ice core, having approximate ages of 4,000 and 6,000 years, were also analyzed. Ice core graphitic carbon contents were found to be 2.5 and 1.1 ..mu..g L/sup -1/. copyrightAmerican Geophysical Union 1987

Chy-acute-accentlek, P.; Srivastava, V.; Cahenzli, L.; Pinnick, R.G.; Dod, R.L.; Novakov, T.; Cook, T.L.; Hinds, B.D.

1987-08-20T23:59:59.000Z

265

Implications of the UHECRs penetration depth measurements  

E-Print Network [OSTI]

The simple interpretation of PAO's UHECRs' penetration depth measurements suggests a transition at the energy range $1.1 - 35 \\cdot 10^{18} $ eV from protons to heavier nuclei. A detailed comparison of this data with air shower simulations reveals strong restrictions on the amount of light nuclei (protons and He) in the observed flux. We find a robust upper bound on the observed proton fraction of the UHECRs flux and we rule out a composition dominated by protons and He. Acceleration and propagation effects lead to an observed composition that is different from the one at the source. Using a simple toy model that take into account these effects, we show that the observations requires an extreme metallicity at the sources with metals to protons mass ratio of 1:1, a ratio that is larger by a factor of a hundred than the solar abundance. This composition imposes an almost impossible constraint on all current astrophysical models for UHECRs accelerators. This may provide a first hint towards new physics that emerges at $\\sim 100$ TeV and leads to a larger proton cross section at these energies.

Nimrod Shaham; Tsvi Piran

2012-04-06T23:59:59.000Z

266

On The Importance of Organic Oxygen for Understanding Organic Aerosol  

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

On The Importance of Organic Oxygen for Understanding Organic Aerosol On The Importance of Organic Oxygen for Understanding Organic Aerosol Particles Title On The Importance of Organic Oxygen for Understanding Organic Aerosol Particles Publication Type Journal Article Year of Publication 2006 Authors Pang, Yanbo, B. J. Turpin, and Lara A. Gundel Journal Journal of Aerosol Science and Technology Volume 40 Start Page Chapter Pagination 128-133 Abstract This study shows how aerosol organic oxygen data could provide new and independent information about organic aerosol mass, aqueous solubility of organic aerosols, formation of secondary organic aerosol (SOA) and the relative contributions of anthropogenic and biogenic sources. For more than two decades atmospheric aerosol organic mass concentration has usually been estimated by multiplying the measured carbon content by an assumed organic mass (OM)-to-organic carbon (OC ) factor of 1.4. However, this factor can vary from 1.0 to 2.5 depending on location. This great uncertainty about aerosol organic mass limits our understanding of the influence of organic aerosol on climate, visibility and health.New examination of organic aerosol speciation data shows that the oxygen content is the key factor responsible for the observed range in the OM-to-OC factor. When organic oxygen content is excluded, the ratio of non-oxygen organic mass to carbon mass varies very little across different environments (1.12 to 1.14). The non-oxygen-OM-to-non-oxygen OC factor for all studied sites (urban and non-urban) is 1.13± 0.02. The uncertainty becomes an order of magnitude smaller than the uncertainty in the best current estimates of organic mass to organic carbon ratios (1.6± 0.2 for urban and 2.1± 0.2 for non-urban areas). When aerosol organic oxygen data become available, organic aerosol mass can be quite accurately estimated using just OC and organic oxygen (OO) without the need to know whether the aerosol is fresh or aged. In addition, aerosol organic oxygen data will aid prediction of water solubility since compounds with OO-to-OC higher than 0.4 have water solubilities higher than 1g per 100 g water

267

Aerosol generation and entrainment model for cough simulations.  

E-Print Network [OSTI]

??The airborne transmission of diseases is of great concern to the public health community. The possible spread of infectious disease by aerosols is of particular (more)

Ersahin, Cem.

2007-01-01T23:59:59.000Z

268

ARM AOS Processing Status and Aerosol Intensive Properties VAP  

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

Andrews, and P. J. Sheridan National Oceanic and Atmospheric Administration Boulder, Colorado Abstract The Atmospheric Radiation Measurement (ARM) Aerosol Observing System (AOS)...

269

Method of Preparing Super-Concentrated Jets From Dense Aerosol...  

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

Michael J. Hay, Ernest J. Valeo, and Nathaniel J. Fisch This is improvement in aerodynamic focusing of dilute aerosol suspensions. All previous work on this subject has...

270

ARM - Field Campaign - Pajarito Aerosol Coupling to Ecosystems...  

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

properties during the winter-spring transition. Opportunity to investigate fire and automobile emission interactions with biogenic aerosols will also harnessed MAOS will be...

271

Heavy Duty Diesel Engine Exhaust Aerosol Particle and Ion Measurements  

Science Journals Connector (OSTI)

Heavy Duty Diesel Engine Exhaust Aerosol Particle and Ion Measurements ... diesel engines have received increasing attention due to their potential health effects. ...

Tero Lhde; Topi Rnkk; Annele Virtanen; Tanja J. Schuck; Liisa Pirjola; Kaarle Hmeri; Markku Kulmala; Frank Arnold; Dieter Rothe; Jorma Keskinen

2008-12-09T23:59:59.000Z

272

Raman Lidar Measurements of Aerosols and Water Vapor During the...  

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

modifications reduced but could not eliminate these adverse effects. The Raman lidar water vapor (aerosol extinction) measurements produced by these modified algorithms were,...

273

aerosol influenza transmission: Topics by E-print Network  

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

and Information Sciences Websites Summary: . In preliminary work, we used artificial neural networks (ANNs) to construct global aerosol predictors by learningIntegration...

274

E-Print Network 3.0 - aerosol particle size Sample Search Results  

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

Summary: of aerosol over many orders-of-magnitude of particle size range, from subcritical clusters on the molecular... to modeling aerosol dynamics under conditions of new...

275

E-Print Network 3.0 - aerosol modeling decadal Sample Search...  

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

Geosciences 8 Absorbing aerosols and pre-summer monsoon hydroclimate variability over the Indian subcontinent: The challenge in investigating links Summary: in the aerosol-monsoon...

276

E-Print Network 3.0 - aerosol radiative forcing Sample Search...  

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

No. DE- Summary: : WHY MEASUREMENTS ALONE CANNOT QUANTIFY AEROSOL RADIATIVE FORCING OF CLIMATE CHANGE Stephen E. Schwartz... of radiative forcing of climate change by aerosols,...

277

E-Print Network 3.0 - aerosols nanometriques application Sample...  

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

is studying how aerosol particles affect everything from Summary: of aerosol particles on climate change, public health, and renewable energy applications. In particular, he......

278

E-Print Network 3.0 - aerosol lung inhalation Sample Search Results  

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

aerosolized by means... is aerosolized upon inhalation by utilizing the ... Source: Groningen, Rijksuniversiteit - Centre for Ecological and Evolutionary Studies, Department of...

279

E-Print Network 3.0 - aerosol condensation model Sample Search...  

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

Applied Science Collection: Environmental Sciences and Ecology 8 DETERMINING AEROSOL RADIATIVE FORCING AT ARM SITES Summary: OF AEROSOL DIRECT FORCING By linear model and by...

280

E-Print Network 3.0 - aerosol code comparisons Sample Search...  

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

and Ecology 4 Estimates of global radiative forcing derived from the GlobAEROSOL dataset Summary: -sky direct aerosol radiative forcing. The Edwards and Slingo (1996)...

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Aerosol-Cloud-Precipitation Interactions in the Trade Wind Boundary Layer.  

E-Print Network [OSTI]

??This dissertation includes an overview of aerosol, cloud, and precipitation properties associated with shallow marine cumulus clouds observed during the Barbados Aerosol Cloud Experiment (BACEX, (more)

Jung, Eunsil

2012-01-01T23:59:59.000Z

282

E-Print Network 3.0 - aerosols harbor diverse Sample Search Results  

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

Cloud & Aerosol Process Group CSDESRLNOAA Presented at: NIST... Aerosol Metrology for Climate Workshop 15th March, 2011 12;Deposition Snow Darkens and Warms BC...

283

E-Print Network 3.0 - aerosol light absorption Sample Search...  

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

AND Summary: population centers were used to calculate the aerosol forcing due to light scattering and absorption. Directly... , NY www.bnl.gov ABSTRACT Aerosols influence...

284

Large Aerosols Play Unexpected Role in Ganges Valley | U.S. DOE...  

Office of Science (SC) Website

The data have revealed that large aerosols in this region absorb a greater amount of light than expected. The Science Aerosol particles in the atmosphere may absorb solar...

285

E-Print Network 3.0 - aerosol atmospheric interactions Sample...  

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

for Climate Summary: order estimates of aerosol-climate interaction But... only Earth System Models can include all... of the interactions (in theory at least) 12;Aerosols <>...

286

E-Print Network 3.0 - alkali sulfate aerosol Sample Search Results  

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

Aerosol Formation during... " and "Mechanism of Alkali Sulfate Aerosols Formation during Biomass Combustion" describe the development... the ... Source: Ris National Laboratory...

287

E-Print Network 3.0 - atmospheric aerosol size Sample Search...  

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

for about ten percent of all aerosols in the atmosphere. We... , can actually absorb solar energy and warm the atmosphere. Atmospheric aerosols are very important... by...

288

Nonimaging Optics  

Science Journals Connector (OSTI)

The nonimaging optical system, by definition, does not produce an image of the light source. Instead, it is designed to concentrate radiation at a density as high as theoretically possible. Nonimaging optics h...

Dr. Ralf Leutz; Dr. Akio Suzuki

2001-01-01T23:59:59.000Z

289

Optical Switch  

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

seven wonders Optical Switch A key component in the laser chain, an optical switch called a plasma electrode Pockels cell (PEPC), was invented and developed at LLNL. A Pockels cell...

290

Development of Aerosol Models for Radiative Flux Calculations at ARM Sites: Utility of Trajectory Clustering for Characterizing Aerosol Climatology  

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

Development of Aerosol Models for Radiative Flux Development of Aerosol Models for Radiative Flux Calculations at ARM Sites: Utility of Trajectory Clustering for Characterizing Aerosol Climatology E. Andrews Cooperative Institute for Research in the Environment University of Colorado Boulder, Colorado E. Andrews, J. A. Ogren, P. J. Sheridan, and J. M. Harris Climate Monitoring and Diagnostics Laboratory National Oceanic and Atmospheric Administration Boulder, Colorado P. K. Quinn Pacific Marine Environmental Laboratory National Oceanic and Atmospheric Administration Seattle, Washington Abstract The uncertainties associated with assumptions of generic aerosol properties in radiative transfer codes are unknown, which means that these uncertainties are frequently invoked when models and

291

Recovery of SIMS depth profiles with account for nonstationary effects  

Science Journals Connector (OSTI)

Abstract In this work we consider a method of accounting for the nonstationary effects in recovery of SIMS depth profiles. The depth resolution function (DRF) is described by Hofmann's nonstationary MRI (mixing-roughness-information depth) model using the depth-dependent parameters. The effects in question include the nonstationary atomic mixing and development of surface roughness. A mathematical description of the nonstationary depth profiling process by the Fredholm integral equation of the first kind is proposed. The inverse problem is solved using an algorithm based on the Tikhonov regularization method. The proposed nonstationary recovery method is tested on both model and real structures. The development of surface roughness in SIMS depth profiling of the real structure was observed. Grazing incidence x-ray reflectometry (XRR) technique was used to verify the results of SIMS profiles restoration for periodic structure containing thin Ge layers in the Si matrix. The advantages of the proposed recovery algorithm to allow for the nonstationary effects are shown.

Pavel Andreevich Yunin; Yurii Nikolaevich Drozdov; Mikhail Nikolaevich Drozdov; Dmitry Vladimirovich Yurasov

2014-01-01T23:59:59.000Z

292

Defense-in-Depth, How Department of Energy Implements Radiation...  

Office of Environmental Management (EM)

is implemented using a defense-in-depth approach taking into account the combination of natural and engineered barriers, performance objectives, long-term risk assessments,...

293

Advanced Technology Vehicle Lab Benchmarking - Level 2 (in-depth...  

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

Evaluation Meeting vss031rask2012o.pdf More Documents & Publications Advanced Technology Vehicle Lab Benchmarking - Level 2 (in-depth) Advanced Technology Vehicle Lab...

294

Are Cluster Ion Analysis Beams Good Choices for Hydrogen Depth...  

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

Cluster Ion Analysis Beams Good Choices for Hydrogen Depth Profiling Using Time-of-Flight Secondary Ion Mass Spectrometry? Are Cluster Ion Analysis Beams Good Choices for Hydrogen...

295

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

Broader source: Energy.gov (indexed) [DOE]

that use control system networks while maintaining a multi-tier information architecture. Control Systems Cyber Security: Defense in Depth Strategies More Documents &...

296

BOUDREAU, BERNARD P. Mean mixed depth of sediments: The ...  

Science Journals Connector (OSTI)

bioturbation. Bioturbation is the mixing of surficial sediments as a re- sult of the activity .... that the mixed depth is limited by the increasing energy costs of deeper

2000-10-17T23:59:59.000Z

297

Physicochemical Characterization of Capstone Depleted Uranium Aerosols I: Uranium Concentration in Aerosols as a Function of Time and Particle Size  

SciTech Connect (OSTI)

During the Capstone Depleted Uranium (DU) Aerosol Study, aerosols containing depleted uranium were produced inside unventilated armored vehicles (i.e., Abrams tanks and Bradley Fighting Vehicles) by perforation with large-caliber DU penetrators. These aerosols were collected and characterized, and the data were subsequently used to assess human health risks to personnel exposed to DU aerosols. The DU content of each aerosol sample was first quantified by radioanalytical methods, and selected samples, primarily those from the cyclone separator grit chambers, were analyzed radiochemically. Deposition occurred inside the vehicles as particles settled on interior surfaces. Settling rates of uranium from the aerosols were evaluated using filter cassette samples that collected aerosol as total mass over eight sequential time intervals. A moving filter was used to collect aerosol samples over time particularly within the first minute after the shot. The results demonstrate that the peak uranium concentration in the aerosol occurred in the first 10 s, and the concentration decreased in the Abrams tank shots to about 50% within 1 min and to less than 2% 30 min after perforation. In the Bradley vehicle, the initial (and maximum) uranium concentration was lower than those observed in the Abrams tank and decreased more slowly. Uranium mass concentrations in the aerosols as a function of particle size were evaluated using samples collected in the cyclone samplers, which collected aerosol continuously for 2 h post perforation. The percentages of uranium mass in the cyclone separator stages from the Abrams tank tests ranged from 38% to 72% and, in most cases, varied with particle size, typically with less uranium associated with the smaller particle sizes. Results with the Bradley vehicle ranged from 18% to 29% and were not specifically correlated with particle size.

Parkhurst, MaryAnn; Cheng, Yung-Sung; Kenoyer, Judson L.; Traub, Richard J.

2009-03-01T23:59:59.000Z

298

CLOUD PHYSICS From aerosol-limited to invigoration  

E-Print Network [OSTI]

CLOUD PHYSICS From aerosol-limited to invigoration of warm convective clouds Ilan Koren,1 * Guy Dagan,1 Orit Altaratz1 Among all cloud-aerosol interactions, the invigoration effect is the most elusive. Most of the studies that do suggest this effect link it to deep convective clouds with a warm base

Napp, Nils

299

Deposition of Biological Aerosols on HVAC Heat Exchangers  

E-Print Network [OSTI]

LBNL-47669 Deposition of Biological Aerosols on HVAC Heat Exchangers Jeffrey Siegel and Iain Walker of Biological Aerosols on HVAC Heat Exchangers Jeffrey A. Siegel Iain S. Walker, Ph.D. ASHRAE Student Member that are found in commercial and residential HVAC systems of 1 - 6 m/s (200 - 1200 ft/min), particle diameters

300

Determination of vertical profiles of aerosol extinction, single scatter  

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

Determination of vertical profiles of aerosol extinction, single scatter Determination of vertical profiles of aerosol extinction, single scatter albedo and asymmetry parameter at Barrow. Sivaraman, Chitra Pacific Northwest National Laboratory Flynn, Connor Pacific Northwest National Laboratory Turner, David University of Wisconsin-Madison Category: Aerosols Efforts are currently underway to run and evaluate the Broadband Heating Rate Profile project at the ARM North Slope of Alaska (NSA) Barrow site for the time period March 2004 - February 2005. The Aerosol Best-Estimate (ABE) Value-Added Procedure (VAP) is to provide continuous estimates of vertical profiles of aerosol extinction, single-scatter albedo, and asymmetry parameter above the Northern Slopes of Alaska (NSA) facility. In the interest of temporal continuity, we have developed an algorithm that

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Aerosol Retrievals under Partly Cloudy Conditions: Challenges and Perspectives  

SciTech Connect (OSTI)

There are lots of interesting and intriguing features of aerosols near clouds many of which can be quite engaging, as well being useful and climate-related. Exploring aerosol with the aid of the remote sensing, in situ observations and numerical modeling has piqued our curiosity and led to improve insights into the nature of aerosol and clouds and their complex relationship. This chapter conveys the outstanding issues of cloudy-sky aerosol retrievals of important climate properties and outlines their fruitful connections to other research areas such as in situ measurements and model simulations. The chapter focuses mostly on treating the inverse problems in the context of the passive satellite remote sensing and how they can improve our understanding of the cloud-aerosol interactions. The presentation includes a basis in the inverse problem theory, reviews available approaches and discusses their applications to partly cloudy situations. Potential synergy of observations and model simulations is described as well.

Kassianov, Evgueni I.; Ovchinnikov, Mikhail; Berg, Larry K.; Flynn, Connor J.

2011-06-01T23:59:59.000Z

302

Atmospheric aerosol monitoring at the Pierre Auger Observatory  

SciTech Connect (OSTI)

For a ground based cosmic-ray observatory the atmosphere is an integral part of the detector. Air fluorescence detectors (FDs) are particularly sensitive to the presence of aerosols in the atmosphere. These aerosols, consisting mainly of clouds and dust, can strongly affect the propagation of fluorescence and Cherenkov light from cosmic-ray induced extensive air showers. The Pierre Auger Observatory has a comprehensive program to monitor the aerosols within the atmospheric volume of the detector. In this paper the aerosol parameters that affect FD reconstruction will be discussed. The aerosol monitoring systems that have been deployed at the Pierre Auger Observatory will be briefly described along with some measurements from these systems.

Cester, R.; Chiosso, M.; Chirin, J.; Clay, R.; Dawson, B.; Fick, B.; Filipcic, A.; Garcia, B.; Grillo, A.; Horvat, M.; Iarlori, M.; Malek, M.; Matthews, J.; Matthews,; Melo, D.; Meyhandan, R.; Mostafa, M.; Mussa, R.; Prouza, M.; Raefert, B.; Rizi, V.

2005-07-01T23:59:59.000Z

303

Chemical Depth Profiling from Neutron Reflectometry  

SciTech Connect (OSTI)

The material profile of a thin film can be analyzed by placing the film on a substrate and by sending a neutron beam onto it at various angles of incidence. Technically, the scattering length density of the film needs to be determined as a function of depth. A reflectometer is used to measure the amount of reflection (reflectivity) as a function of the angle of incidence. Mathematically, this is equivalent to sending the neutron beam onto the film at every energy but at a fixed angle of incidence. The film profile needs to be recovered from the measured reflectivity data. Unfortunately, the unique recovery is impossible, and many distinct unrelated profiles may correspond to the same reflectivity data. In our DOE/EPSCoR sponsored research, we have developed an analytical method to uniquely recover the profile of a thin film from the measured reflectivity data. We have shown that by taking reflectivity measurements with two different substrates, one can uniquely determine the film profile. Previously, it was known that one could uniquely recover the profile by taking reflectivity measurements with three different substrates, and our findings indicate that the same goal can be accomplished by using fewer measurements. At Mississippi State University we started an informal weekly seminar (called ''the reflectometry meeting'') at to attract various undergraduate and graduate students into the field. There were about 3 undergraduate students, 6 graduate students, and 2 faculty members attending these seminars. The PI has collaborated with Dr. Norm Berk at National Institute of Standards and Technology (NIST) on various aspects of neutron reflectometry, from which various interesting problems of theoretical and practical importance have arisen. One of these problems is closely related to the important mathematical problem known as analytic extrapolation. Under appropriate conditions (known to hold in neutron reflectometry), the reflection data taken in a finite interval of neutron energies uniquely determines the data at all energies. Even though the uniqueness is assured mathematically, there are currently no available methods for analytic extrapolation. Currently, we are working on this problem as it arises in neutron reflectometry and looking for mathematical and numerical methods to extrapolate reflection data to higher and lower neutron energies. A solution to this problem is expected to have a big impact not only in neutron reflectometry, but in many areas of physics and engineering. The PI has collaborated with Prof. Paul Sacks of Iowa State University, Prof. Daniil Sarkissian of Mississippi State University, and Prof. Levon Babadzanjanz of St. Petersburg State University, Russia on mathematical and numerical aspects of neutron reflectometry. These researchers jointly worked with the PI towards the preparation of numerical routines to extract the film profile from the reflection data. We have prepared a Mathematica interface running Fortran 95 algorithms to produce reflection data from a given profile. These Fortran 95 algorithms have been prepared by updating and modifying Prof. Sacks' Fortran 77 routine and by updating Dr. Gian Felcher's (of Argonne National Laboratory) Fortran 77 routine. We are also preparing similar algorithms written in Mathematica so that they can be used without needing Fortran. We are also working towards preparing algorithms in Fortran 95 and in Mathematica to produce the film profile from the given sets of reflectivity data.

Tuncay Aktosun

2006-03-21T23:59:59.000Z

304

Optimization of aerosol penetration through transport lines  

E-Print Network [OSTI]

, F is the numerical reading from the fluorometer , L is the liquid volume of the measured (23) solution, 8 is the testing time for each filter, and V is the filter flow rate during the sample period. Penetration, P, of aerosol through... defined maxima on the penetration versus Reynolds number (or flow rate, since the diameter is constant for a given tube) curves for each tube size. Also, in order to observe an optimum tube diameter , a (10) fixed flow rate of 86 L/min was tested for a...

Wong Luque, Fermin Samuel

2012-06-07T23:59:59.000Z

305

A shrouded probe aerosol sampling cyclone  

E-Print Network [OSTI]

the air stream. In the present design, three concentric shrouds and a probe will be attached to the entrance of the cyclone. The shroud concept was first used in an aircraft-horne sampling device for collecting tropospheric aerosol particles... by A. R. McFarland and S. A. Batterman. College Station, Texas: 1989. 5. Strauss, W. and S. J. Nainwaring: Air Pollution. London, Baltimore, Maryland: Edward Arnold, 1984. pp. 95-96. 6. Moore, N. E. , and A. R. NcFarland: Stairmand-Type Sampling...

Little, Stewart Craig

2012-06-07T23:59:59.000Z

306

Method of dispersing particulate aerosol tracer  

DOE Patents [OSTI]

A particulate aerosol tracer which comprises a particulate carrier of sheet silicate composition having a particle size up to one micron, and a cationic dopant chemically absorbed in solid solution in the carrier. The carrier is preferably selected from the group consisting of natural mineral clays such as bentonite, and the dopant is selected from the group consisting of rare earth elements and transition elements. The tracers are dispersed by forming an aqueous salt solution with the dopant present as cations, dispersing the carriers in the solution, and then atomizing the solution under heat sufficient to superheat the solution droplets at a level sufficient to prevent reagglomeration of the carrier particles.

O'Holleran, Thomas P. (Belleville, MI)

1988-01-01T23:59:59.000Z

307

Light Absorption by Secondary Organic Aerosol from ?-Pinene: Effects of Oxidants, Seed Aerosol Acidity, and Relative Humidity  

SciTech Connect (OSTI)

It is well known that light absorption from dust and black carbon aerosols has a warming effect on climate while light scattering from sulfate, nitrate, and sea salt aerosols has a cooling effect. However, there are large uncertainties associated with light absorption and scattering by different types of organic aerosols, especially in the near-UV and UV spectral regions. In this paper, we present the results from a systematic laboratory study focused on measuring light absorption by secondary organic aerosols (SOA) generated from ozonolysis or NO3 oxidation of ?-pinene in the presence of neutral and acidic sulfate seed aerosols. Light absorption was monitored using photoacoustic spectrometers at four different wavelengths: 355, 405, 532 and 870 nm. Light absorption at 355 and 405 nm was observed by SOA generated from oxidation of ?-pinene in the presence of acidic sulfate seed aerosols, under dry conditions. No absorption was observed when the relative humidity was elevated to greater than 27%, or in the presence of neutral sulfate seed aerosols. The light-absorbing compounds are speculated to be aldol condensation oligomers with organosulfate and organic nitrate groups. The results of this study also indicate that organic nitrates from ?-pinene SOA formed in the presence of neutral sulfate seed aerosols do not appear to absorb near-UV and UV radiation.

Song, Chen; Gyawali, Madhu S.; Zaveri, Rahul A.; Shilling, John E.; Arnott, W. Patrick

2013-10-25T23:59:59.000Z

308

Sources and Formation of OrganicSources and Formation of Organic Aerosols in our AtmosphereAerosols in our Atmosphere  

E-Print Network [OSTI]

;Carnegie Mellon University Smog Chamber Air supply Computer Temperature control Clean air 10 m3 Teflon spectrometer Aerosol mass spectrometerOzone monitor Air supply Computer Temperature control Clean air 10 m3 on temperature Hevap also needed Assumes no interactions among organic aerosol species or with inorganics. #12

Einat, Aharonov

309

IMPROVED BOUSSINESQ-TYPE EQUATIONS FOR HIGHLY-VARIABLE DEPTH  

E-Print Network [OSTI]

IMPROVED BOUSSINESQ-TYPE EQUATIONS FOR HIGHLY-VARIABLE DEPTH JUAN CARLOS MU~NOZ GRAJALES AND ANDR´E NACHBIN Abstract. Intermediate depth, Boussinesq-type modeling is used to generalize previously known are extended from the analysis of KdV-type models to include the improved Boussinesq systems in contrast

Nachbin, André

310

Depth, and Motion inVision CMSC 436/636  

E-Print Network [OSTI]

, perceived depth related #12;Head Motion Parallax Bruce and Green 90, p. 231. Kinetic Depth Effect Bruce displacement) #12;Structure from Motion Bruce and Green 90, pg. 328. #12;Image Segmentation Discontinuities Representation techniques parameters #12;Experimental Findings Control necessary for development Held

Rheingans, Penny

311

SEU sensitive depth in a submicron SRAM technology  

SciTech Connect (OSTI)

This work determines experimentally and by simulation the SEU sensitive depth in a 0.6 {micro}m SRAM technology. A good correlation is obtained between the two studies in the case of heavy ions deposing energy close to the critical energy. Other simulation results complete the first investigation by studying the minimum sensitive depth for ions deposing higher energies (at greater LET).

Detcheverry, C.; Bruguier, G.; Palau, J.M.; Gasiot, J. [Univ. Montpellier II (France)] [Univ. Montpellier II (France); Ecoffet, R. [CNES, Toulouse (France)] [CNES, Toulouse (France); Duzellier, S. [DERTS, Toulouse (France)] [DERTS, Toulouse (France); Barak, J.; Lifshitz, Y. [Soreq NRC, Yahvne (Israel)] [Soreq NRC, Yahvne (Israel)

1998-06-01T23:59:59.000Z

312

On depth and deep points: a calculus Ivan Mizera  

E-Print Network [OSTI]

of Tukey's median) plays a fundamental role similar to that of linear functions in the mathematical (1929) and Chamberlin (1933). For multivariate location, the proposal of Tukey (1975) was developed halfspace or Tukey's depth; for other brands of depth in multivariate location see Liu, Parelius and Singh

Mizera, Ivan

313

Beryllium Carcinogenesis. I. Inhalation Exposure of Rats to Beryllium Sulfate Aerosol  

Science Journals Connector (OSTI)

...aerosol at a mean atmospheric concentration of...aerosol at a mean atmospheric concentration of...in the drinking water) for 2 weeks...a glass aerosol generator, with an airflow...chamber, distilled water was disseminated...aerosol generation, atmospheric concentration control...

Andrew L. Reeves; Daniel Deitch; and Arthur J. Vorwald

1967-03-01T23:59:59.000Z

314

Improving aerosol distributions below clouds by assimilating satellite-retrieved cloud droplet number  

Science Journals Connector (OSTI)

...remainder of the map to the...distributions for mass, number, composition...such as vertical velocity and aerosol composition...updated aerosol mass for each compound...aerosols in trade wind cumulus observed by...spectrum of updraft velocities and the internally...Starting from aerosol mass (M) and number...

Pablo E. Saide; Gregory R. Carmichael; Scott N. Spak; Patrick Minnis; J. Kirk Ayers

2012-01-01T23:59:59.000Z

315

spectra from size-resolved particle samples col-lected from the Southeastern Aerosol Visibility  

E-Print Network [OSTI]

and acrolein aerosols. We believe that these transformations are due to acid-catalyzed heterogeneous reac

Bishop, James K.B.

316

OPTICS 5  

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

OPTICS (Version 5.1.02) OPTICS (Version 5.1.02) Release notes NOTE: See the Optics Knowledge Base for how to run this version of Optics on the Microsoft Vista and Microsoft Windows 7 operating systems March 5, 2003: Release Maintenance Pack 2 New ! January 7, 2003: Release Maintenance Pack 1 October 23, 2002: Release Optics 5.1.01 September 27, 2002: Release Optics 5.1.00 (only released on CDs at NFRC Annual Fall Meeting) Release notes Maintenance Pack 2 Bug fixes: New features: bullet Applied films that were created could not be saved or exported. This has been fixed. bullet Exporting glazing systems generated a message that the operation failed because the glazing system type is unknown. Glazing systems can now be exported to file (e.g. to view the spectral data), but the structure information will be lost.

317

Property:AvgReservoirDepth | Open Energy Information  

Open Energy Info (EERE)

AvgReservoirDepth AvgReservoirDepth Jump to: navigation, search Property Name AvgReservoirDepth Property Type Quantity Description Average depth to reservoir Use this type to express a quantity of length. The default unit is the meter (m). Acceptable units (and their conversions) are: Meters - 1 m, meter, meters Meter, Meters, METER, METERS Kilometers - 0.001 km, kilometer, kilometers, Kilometer, Kilometers, KILOMETERS, KILOMETERS Miles - 0.000621371 mi, mile, miles, Mile, Miles, MILE, MILES Feet - 3.28084 ft, foot, feet, Foot, Feet, FOOT, FEET Yards - 1.09361 yd, yard, yards, Yard, Yards, YARD, YARDS Pages using the property "AvgReservoirDepth" Showing 24 pages using this property. A Amedee Geothermal Area + 213 m0.213 km 0.132 mi 698.819 ft 232.939 yd + B Beowawe Hot Springs Geothermal Area + 850 m0.85 km

318

Optical Magnetism  

Science Journals Connector (OSTI)

Magnetic dipole radiation one fourth as intense as electric dipole radiation, as well as a novel nonlinear magneto-optical effect are reported in dielectric media.

Oliveira, Samuel L; Rand, Stephen C

319

Sulfate aerosols and polar stratospheric cloud formation  

SciTech Connect (OSTI)

Before the discovery of the Antarctic ozone hole, it was generally assumed that gas-phase chemical reactions controlled the abundance of stratospheric ozone. However, the massive springtime ozone losses over Antarctica first reported by Farman et al in 1985 could not be explained on the basis of gas-phase chemistry alone. In 1986, Solomon et al suggested that chemical reactions occurring on the surfaces of polar stratospheric clouds (PSCs) could be important for the observed ozone losses. Since that time, an explosion of laboratory, field, and theoretical research in heterogeneous atmospheric chemistry has occurred. Recent work has indicated that the most important heterogeneous reaction on PSCs is ClONO[sub 2] + HCl [yields] Cl[sub 2] + HNO[sub 3]. This reaction converts inert chlorine into photochemically active Cl[sub 2]. Photolysis of Cl[sub 2] then leads to chlorine radicals capable of destroying ozone through very efficient catalytic chain reactions. New observations during the second Airborne Arctic Stratospheric Expedition found stoichiometric loss of ClONO[sub 2] and HCl in air processed by PSCs in accordance with reaction 1. Attention is turning toward understanding what kinds of aerosols form in the stratospheric, their formation mechanism, surface area, and specific chemical reactivity. Some of the latest findings, which underline the importance of aerosols, were presented at a recent National Aeronautics and Space Administration workshop in Boulder, Colorado.

Tolbert, M.A. (Univ. of Colorado, Boulder, CO (United States))

1994-04-22T23:59:59.000Z

320

CARES Helps Explain Secondary Organic Aerosols  

ScienceCinema (OSTI)

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.

Zaveri, Rahul

2014-06-02T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Optical Expanders with Applications in Optical Computing  

E-Print Network [OSTI]

Optical Expanders with Applications in Optical Computing John H. Reif Akitoshi Yoshida July 20, 1999 Abstract We describe and investigate an optical system which we call an optical expander. An optical expander elec- trooptically expands an optical boolean pattern encoded in d bits into an optical

Reif, John H.

322

Infrared Optical Constants of Highly Diluted Sulfuric Acid Solution Droplets at Cirrus Temperatures  

Science Journals Connector (OSTI)

The data evaluation procedure, previously developed for open-path TDLAS measurements in combustion processes,(28) water sprays,(29) and on stratospheric balloon platforms,(30) ensured a precise correction of the broadband optical scattering losses caused by the aerosol and cloud particles along the absorption path, as well as the pressure and temperature changes during the expansion. ...

Robert Wagner; Stefan Benz; Helmut Bunz; Ottmar Mhler; Harald Saathoff; Martin Schnaiter; Thomas Leisner; Volker Ebert

2008-10-22T23:59:59.000Z

323

Optical Glass  

Science Journals Connector (OSTI)

... space of time. In the forefront of such vital industries is the manufacture of optical glass. However great the other resources in men and material may be, it would be ... be, it would be quite impossible to wage successful warfare without adequate supplies of optical glass ior binocular field- ...

1919-03-27T23:59:59.000Z

324

A New Aerosol Flow System for Photochemical and Thermal Studies of Tropospheric Aerosols  

SciTech Connect (OSTI)

For studying the formation and photochemical/thermal reactions of aerosols relevant to the troposphere, a unique, high-volume, slow-flow, stainless steel aerosol flow system equipped with 5 UV lamps has been constructed and characterized experimentally. The total flow system length 6 is 8.5 m and includes a 1.2 m section used for mixing, a 6.1 m reaction section and a 1.2 m 7 transition cone at the end. The 45.7 cm diameter results in a smaller surface to volume ratio than is found in many other flow systems and thus reduces the potential contribution from wall reactions. The latter are also reduced by frequent cleaning of the flow tube walls which is made feasible by the ease of disassembly. The flow tube is equipped with ultraviolet lamps for photolysis. This flow system allows continuous sampling under stable conditions, thus increasing the amount of sample available for analysis and permitting a wide variety of analytical techniques to be applied simultaneously. The residence time is of the order of an hour, and sampling ports located along the length of the flow tube allow for time-resolved measurements of aerosol and gas-phase products. The system was characterized using both an inert gas (CO2) and particles (atomized NaNO3). Instruments interfaced directly to this flow system include a NOx analyzer, an ozone analyzer, relative humidity and temperature probes, a scanning mobility particle sizer spectrometer, an aerodynamic particle sizer spectrometer, a gas chromatograph-mass spectrometer, an integrating nephelometer, and a Fourier transform infrared spectrophotometer equipped with a long path (64 m) cell. Particles collected with impactors and filters at the various sampling ports can be analyzed subsequently by a variety of techniques. Formation of secondary organic aerosol from ?-pinene reactions (NOx photooxidation and ozonolysis) are used to demonstrate the capabilities of this new system.

Ezell, Michael J.; Johnson, Stanley N.; Yu, Yong; Perraud, Veronique; Bruns, Emily; Alexander, M. L.; Zelenyuk, Alla; Dabdub, Donald; Finlayson-Pitts, Barbara J.

2010-05-01T23:59:59.000Z

325

Fiber optic coupled optical sensor  

DOE Patents [OSTI]

A displacement sensor includes a first optical fiber for radiating light to a target, and a second optical fiber for receiving light from the target. The end of the first fiber is adjacent and not axially aligned with the second fiber end. A lens focuses light from the first fiber onto the target and light from the target onto the second fiber.

Fleming, Kevin J. (Albuquerque, NM)

2001-01-01T23:59:59.000Z

326

Understanding Fault Characteristics And Sediment Depth For Geothermal  

Open Energy Info (EERE)

Understanding Fault Characteristics And Sediment Depth For Geothermal Understanding Fault Characteristics And Sediment Depth For Geothermal Exploration Using 3D Gravity Inversion In Walker Valley, Nevada Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Understanding Fault Characteristics And Sediment Depth For Geothermal Exploration Using 3D Gravity Inversion In Walker Valley, Nevada Details Activities (2) Areas (1) Regions (0) Abstract: The Southern Walker Lake Basin, situated in the Walker Lake structural domain, consists of primarily E-W directed extension along N-NNW striking normal faults. Water well drilling on the eastern slopes of the Wassuk Range, west of the city of Hawthorne, Nevada showed elevated temperatures. Two recent drill holes reaching downhole depths of more than 4000 ft give some insight to the geologic picture, but more information

327

Extended depth secondary recovery: more coal for the 80's  

SciTech Connect (OSTI)

There are a variety of surface mining techniques presently in use which are physically or economically unable to recover all of the coal available. A new technique known as extended depth secondary recovery is presently available in the form of the Thin Seam Miner, which is able to recover 80-85% of this otherwise lost coal, to depths of 220 feet. Extended depth secondary recovery began with the auger, which has enjoyed moderate success, despite major drawbacks. Punch mining, longwall and shortwall technologies and the push-button miner all attempted to economically remine areas, with very little success. The Thin Seam Miner, on the other hand, not only recovers 80-85% of the coal in place to depths of 220 feet, but is environmentally sound, economically feasible, safe, and adapted to mine under all the seam conditions and grades of coal found in Appalachia.

Shearer, L.K.

1982-12-01T23:59:59.000Z

328

Method and apparatus to measure the depth of skin burns  

DOE Patents [OSTI]

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.

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

2002-01-01T23:59:59.000Z

329

Understanding Fault Characteristics And Sediment Depth For Geothermal...  

Open Energy Info (EERE)

Fault Characteristics And Sediment Depth For Geothermal Exploration Using 3D Gravity Inversion In Walker Valley, Nevada Jump to: navigation, search OpenEI Reference LibraryAdd to...

330

Depth-resolved cathodoluminescence spectroscopy of silicon supersaturated with sulfur  

E-Print Network [OSTI]

We investigate the luminescence of Si supersaturated with S (Si:S) using depth-resolved cathodoluminescence spectroscopy and secondary ion mass spectroscopy as the S concentration is varied over 2 orders of magnitude ...

Fabbri, Filippo

331

Next Generation Nuclear Plant Defense-in-Depth Approach  

SciTech Connect (OSTI)

The purpose of this paper is to (1) document the definition of defense-in-depth and the pproach that will be used to assure that its principles are satisfied for the NGNP project and (2) identify the specific questions proposed for preapplication discussions with the NRC. Defense-in-depth is a safety philosophy in which multiple lines of defense and conservative design and evaluation methods are applied to assure the safety of the public. The philosophy is also intended to deliver a design that is tolerant to uncertainties in knowledge of plant behavior, component reliability or operator performance that might compromise safety. This paper includes a review of the regulatory foundation for defense-in-depth, a definition of defense-in-depth that is appropriate for advanced reactor designs based on High Temperature Gas-cooled Reactor (HTGR) technology, and an explanation of how this safety philosophy is achieved in the NGNP.

Edward G. Wallace; Karl N. Fleming; Edward M. Burns

2009-12-01T23:59:59.000Z

332

Molecular Depth Profiling of Sucrose Films: A Comparative Study...  

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

Cs and O Ions. Abstract: Time-of-flight secondary ion mass spectrometry (ToF-SIMS) depth profiling of sucrose thin films were investigated using 10 keV C60+, 20 keV...

333

Property:FirstWellDepth | Open Energy Information  

Open Energy Info (EERE)

FirstWellDepth FirstWellDepth Jump to: navigation, search Property Name FirstWellDepth Property Type Quantity Use this type to express a quantity of length. The default unit is the meter (m). Acceptable units (and their conversions) are: Meters - 1 m, meter, meters Meter, Meters, METER, METERS Kilometers - 0.001 km, kilometer, kilometers, Kilometer, Kilometers, KILOMETERS, KILOMETERS Miles - 0.000621371 mi, mile, miles, Mile, Miles, MILE, MILES Feet - 3.28084 ft, foot, feet, Foot, Feet, FOOT, FEET Yards - 1.09361 yd, yard, yards, Yard, Yards, YARD, YARDS Pages using the property "FirstWellDepth" Showing 5 pages using this property. B Blue Mountain Geothermal Area + 672 m0.672 km 0.418 mi 2,204.724 ft 734.906 yd + K Kilauea East Rift Geothermal Area + 1,968 m1.968 km

334

Prediction of sinkage depth of footings on soft marine sediments  

E-Print Network [OSTI]

instability on the side walls of the cavity. Footing size and sinkage depth of prototype footings are expected to have a significant effect on side- wall instability. (6) Tests in a geotechnical centrifuge are recommended as one means of studying gravity... instability on the side walls of the cavity. Footing size and sinkage depth of prototype footings are expected to have a significant effect on side- wall instability. (6) Tests in a geotechnical centrifuge are recommended as one means of studying gravity...

Yen, Shihchieh

2012-06-07T23:59:59.000Z

335

Case depth verification of hardened samples with Barkhausen noise sweeps  

SciTech Connect (OSTI)

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.

Santa-aho, Suvi; Vippola, Minnamari; Lepist, 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; Leivisk, Kauko [University of Oulu, Control Engineering Laboratory, P.O. Box 4300, FIN-90014 University of Oulu (Finland)

2014-02-18T23:59:59.000Z

336

Aerosol-Based Duct Sealing Technology  

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

8 8 Aerosol-Based Duct Sealing Technology During the past five years, research has quantified the impacts of residential duct system leakage on HVAC energy consumption and peak electricity demand. A typical house with ducts located in the attic or crawlspace wastes approximately 20% of heating and cooling energy through duct leaks and draws approximately 0.5 KW more electricity during peak cooling periods. A 1991 study indicated that sealing leaks could save close to one Quadrillion Btus per year. (see also Commercializing a New Technology) Because the major cost of sealing leaks in existing air distribution systems is the labor for the location and sealing process, reducing the labor could greatly improve the cost-effectiveness of such a retrofit. Field studies of duct sealing programs performed by HVAC contractors show

337

Compact light-emitting-diode sun photometer for atmospheric optical depth measurements  

Science Journals Connector (OSTI)

A new compact light-emitting diode (LED) sun photometer, in which a LED is used as a spectrally selective photodetector as well as a nonlinear feedback element in the operational...

Acharya, Y B; Jayaraman, A; Ramachandran, S; Subbaraya, B H

1995-01-01T23:59:59.000Z

338

Depth-resolved optical imaging and microscopy of vascular compartment dynamics during somatosensory stimulation  

E-Print Network [OSTI]

,a Jesse Skoch,d Brian J. Bacskai,d Anders M. Dale,b and David A. Boasa a Athinoula A. Martinos Center poor specificity to neuronal events: The MRI-based blood oxygen level dependent (BOLD) signal evolves (Attwell and Iadecola, 2002; Iadecola, 2004). To date, the hemodynamic response has largely just

339

Optical depth measurements by shadow-band radiometers and their uncertainties  

E-Print Network [OSTI]

and Atmospheric Administration Surface Radiation (SURFRAD) Network, and NASA Solar Irradiance Research Network important product of Sun-photometric measurements. [According to the American Meteoro- logical Society (AMS Measurement (ARM) Program [7]. This network con- sists of 21 instruments located at the SGP Central (CF

340

Nonlinear optics  

E-Print Network [OSTI]

Nicolaas Bloembergen, recipient of the Nobel Prize for Physics (1981), wrote Nonlinear Optics in 1964, when the field of nonlinear optics was only three years old. The available literature has since grown by at least three orders of magnitude.The vitality of Nonlinear Optics is evident from the still-growing number of scientists and engineers engaged in the study of new nonlinear phenomena and in the development of new nonlinear devices in the field of opto-electronics. This monograph should be helpful in providing a historical introduction and a general background of basic ideas both for expe

Bloembergen, Nicolaas

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Discrimination between thin cirrus and and tropospheric aerosol using  

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

Discrimination between thin cirrus and and tropospheric aerosol using Discrimination between thin cirrus and and tropospheric aerosol using multiple measurements from Darwin ARCS Mitchell, Ross CSIRO Category: Aerosols Thin cirrus cloud occurs frequently in the tropics, and is often difficult to distinguish from tropospheric aerosol on the basis of temporal variations in ground based measurements, since both can be rather spatially uniform. In this study we investigate their discrimination by combining data from three instruments at the Darwin Atmospheric Radiation and Cloud Station (ARCS): the Cimel sun photometer (CSP), the micropulse lidar (MPL), and the total sky imager (TSI). The study was carried out over the dry season of 2005, with the usual widespread burning of tropical savanna leading to extensive smoke plumes. It is shown that the locus of data in

342

Mobile Climate Observatory for Atmospheric Aerosols in India  

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

Atmospheric Aerosols in India Atmospheric Aerosols in India Nainital, India, was the site chosen for deployment of a portable climate research laboratory to study how aerosols impact clouds and energy transfer in the atmosphere. The well-being of hundreds of millions of residents in northeastern India depends on the fertile land around the Ganges River, which is fed by monsoon rains and runoff from the nearby Himalayan Mountains. Any disturbance to the monsoon rains could threaten the population. In the same region, increased industrial activities due to economic growth are releasing small aerosol particles, such as soot and dust, that absorb and scatter sunlight and thus can change cloud formation processes and the heat distribution in the atmosphere. Such changes could greatly increase or

343

ARM - Field Campaign - Biogenic Aerosols - Effects on Clouds and Climate:  

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

govCampaignsBiogenic Aerosols - Effects on Clouds and Climate: Snowfall govCampaignsBiogenic Aerosols - Effects on Clouds and Climate: Snowfall Experiment Related Campaigns Biogenic Aerosols- Effects on Clouds and Climate 2014.02.01, Petäjä, AMF Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Biogenic Aerosols - Effects on Clouds and Climate: Snowfall Experiment 2014.02.01 - 2014.04.30 Lead Scientist : Dmitri Moisseev Description The snowfall measurement campaign, which will take place during AMF2 deployment in Finland, will focus on understanding snowfall microphysics and characterizing performance of surface based snowfall measurement instruments. This will be achieved by combining triple frequency (X, Ka, W -band) radar observations of vertical structure of the precipitation,

344

PNNL-MILAGRO Aerosol Modeling in Mexico | Open Energy Information  

Open Energy Info (EERE)

PNNL-MILAGRO Aerosol Modeling in Mexico PNNL-MILAGRO Aerosol Modeling in Mexico Jump to: navigation, search Name PNNL-MILAGRO Aerosol Modeling in Mexico Agency/Company /Organization Pacific Northwest National Laboratory Topics Co-benefits assessment Resource Type Dataset, Maps Website http://www.pnl.gov/atmospheric Country Mexico UN Region Latin America and the Caribbean References PNNL-MILAGRO Aerosol Modeling in Mexico[1] "MILGARO surface data includes measurements from Supersites, RAMA (Red Automatica de Monitoreo Atmosferico), Mobile, and Other sites. A description of each site type follows along with a plot of the site locations. Supersites Supersites provide detailed atmospheric chemistry and meteorological measurements; these sites included: T0 (located at the Instituto Mexicano

345

A New Assessment of the Aerosol First Indirect Effect  

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

New Assessment of the Aerosol First Indirect Effect New Assessment of the Aerosol First Indirect Effect Shao, Hongfei Florida State University Liu, Guosheng Florida State University Category: Aerosols The aerosol first indirect effect is known to cool the Earth radiatively. However, its magnitude is very uncertain; large discrepancies exist among the observed values published in the literature. In this study, we first survey the published values of those parameters used for describing the first indirect effect. By analyzing the discrepancies among these values, we show that the first indirect effect has been overestimated by many investigators due to an improper parameter being used. Therefore, we introduce a more meaningful parameter to measure this effect. We estimated the first indirect effect using the new parameter based on observational

346

Effects of operating conditions on a heat transfer fluid aerosol  

E-Print Network [OSTI]

are made over ranges of temperature, pressure and orifice diameters. Aerosol drop size distributions of a HTF are measured by a non-intrusive method of analysis using a Malvern Laser Diffraction Particle Analyzer (Malvern laser). The Malvern laser employs...

Sukmarg, Passaporn

2012-06-07T23:59:59.000Z

347

ARM - Field Campaign - Two-Column Aerosol Project (TCAP): Ground...  

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

Discovery Browse Data Related Campaigns Two-Column Aerosol Project (TCAP) 2012.07.01, Berg, AMF Comments? We would love to hear from you Send us a note below or call us at...

348

ARM - Field Campaign - Two-Column Aerosol Project (TCAP): Winter...  

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

Discovery Browse Data Related Campaigns Two-Column Aerosol Project (TCAP) 2012.07.01, Berg, AMF Comments? We would love to hear from you Send us a note below or call us at...

349

ARM - Field Campaign - Two-Column Aerosol Project (TCAP): Aerial...  

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

Discovery Browse Data Related Campaigns Two-Column Aerosol Project (TCAP) 2012.07.01, Berg, AMF Comments? We would love to hear from you Send us a note below or call us at...

350

ARM - Field Campaign - Two-Column Aerosol Project (TCAP): Airborne...  

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

Discovery Browse Data Related Campaigns Two-Column Aerosol Project (TCAP) 2012.07.01, Berg, AMF Comments? We would love to hear from you Send us a note below or call us at...

351

Application of computational fluid dynamics to aerosol sampling and concentration  

E-Print Network [OSTI]

, FLUENT 6 is used to analyze the performance of aerosol sampling and concentration devices including inlet components (impactors), cyclones, and virtual impactors. The ? ? k model was used to predict particle behavior in Inline Cone Impactor (ICI) and Jet...

Hu, Shishan

2009-05-15T23:59:59.000Z

352

Pressure-flow reducer for aerosol focusing devices  

DOE Patents [OSTI]

A pressure-flow reducer, and an aerosol focusing system incorporating such a pressure-flow reducer, for performing high-flow, atmosphere-pressure sampling while delivering a tightly focused particle beam in vacuum via an aerodynamic focusing lens stack. The pressure-flow reducer has an inlet nozzle for adjusting the sampling flow rate, a pressure-flow reduction region with a skimmer and pumping ports for reducing the pressure and flow to enable interfacing with low pressure, low flow aerosol focusing devices, and a relaxation chamber for slowing or stopping aerosol particles. In this manner, the pressure-flow reducer decouples pressure from flow, and enables aerosol sampling at atmospheric pressure and at rates greater than 1 liter per minute.

Gard, Eric (San Francisco, CA); Riot, Vincent (Oakland, CA); Coffee, Keith (Diablo Grande, CA); Woods, Bruce (Livermore, CA); Tobias, Herbert (Kensington, CA); Birch, Jim (Albany, CA); Weisgraber, Todd (Brentwood, CA)

2008-04-22T23:59:59.000Z

353

Persistent sensitivity of Asian aerosol to emissions of nitrogen oxides  

E-Print Network [OSTI]

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 ...

Kharol, S. K.

354

MELCOR 1. 8. 1 assessment: LACE aerosol experiment LA4  

SciTech Connect (OSTI)

The MELCOR code has been used to simulate LACE aerosol experiment LA4. In this test, the behavior of single- and double-component, hygroscopic and nonhygroscopic, aerosols in a condensing environment was monitored. Results are compared to experimental data, and to CONTAIN calculations. Sensitivity studies have been done on time step effects and machine dependencies; thermal/hydraulic parameters such as condensation on heat structures and on pool surface, and radiation heat transfer; and aerosol parameters such as number of MAEROS components and sections assumed, the degree to which plated aerosols are washed off heat structures by condensate film draining, and the effect of non-default values for shape factors and diameter limits. 9 refs., 50 figs., 13 tabs.

Kmetyk, L.N.

1991-09-01T23:59:59.000Z

355

Distinguishing Aerosol Impacts on Climate Over the Past Century  

E-Print Network [OSTI]

Figure 8a). The IE cooling increases snow/ice by about 10% (Their cooling e?ect on surface temperatures promotes ice androw), cooling from the aerosol DE increases snow/ice cover

Koch, Dorothy

2009-01-01T23:59:59.000Z

356

Linearity of Climate Response to Increases in Black Carbon Aerosols  

Science Journals Connector (OSTI)

The impacts of absorbing aerosols on global climate are not completely understood. This paper presents the results of idealized experiments conducted with the Community Atmosphere Model, version 4 (CAM4), coupled to a slab ocean model (CAM4SOM) ...

Salil Mahajan; Katherine J. Evans; James J. Hack; John E. Truesdale

2013-10-01T23:59:59.000Z

357

Effects of aerosols on deep convective cumulus clouds  

E-Print Network [OSTI]

This work investigates the effects of anthropogenic aerosols on deep convective clouds and the associated radiative forcing in the Houston area. The Goddard Cumulus Ensemble model (GCE) coupled with a spectral-bin microphysics is employed...

Fan, Jiwen

2009-05-15T23:59:59.000Z

358

Impact of aerosols on convective clouds and precipitation  

E-Print Network [OSTI]

: Massachusetts Institute of Technology 77 Massachusetts Avenue, E19-411 Cambridge, MA 02139 (USA) Location to form and a significant attenuator of solar radiation, aerosols affect climate in several ways. Current

359

Continuous air monitor for alpha-emitting aerosol particles  

SciTech Connect (OSTI)

A new alpha Continuous Air Monitor (CAM) sampler is being developed for use in detecting the presence of alpha-emitting aerosol particles. The effort involves design, fabrication and evaluation of systems for the collection of aerosol and for the processing of data to speciate and quantify the alpha emitters of interest. At the present time we have a prototype of the aerosol sampling system and we have performed wind tunnel tests to characterize the performance of the device for different particle sizes, wind speeds, flow rates and internal design parameters. The results presented herein deal with the aerosol sampling aspects of the new CAM sampler. Work on the data processing, display and alarm functions is being done in parallel with the particle sampling work and will be reported separately at a later date. 17 refs., 5 figs., 3 tabs.

McFarland, A.R.; Ortiz, C.A. (Texas A and M Univ., College Station, TX (USA). Dept. of Mechanical Engineering); Rodgers, J.C.; Nelson, D.C. (Los Alamos National Lab., NM (USA))

1990-01-01T23:59:59.000Z

360

Chemical Composition and Cloud Nucleation Ability of Marine Aerosol  

E-Print Network [OSTI]

This study is focused on the chemical composition and cloud nucleation ability of marine aerosol based on two cruise researches over Pacific Ocean and North Atlantic Ocean respectively. Implications of CLAW hypothesis and the factors influencing its...

Deng, Chunhua

2013-12-12T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Computational Fluid Dynamics Study of Aerosol Transport and Deposition Mechanisms  

E-Print Network [OSTI]

In this work, various aerosol particle transport and deposition mechanisms were studied through the computational fluid dynamics (CFD) modeling, including inertial impaction, gravitational effect, lift force, interception, and turbophoresis, within...

Tang, Yingjie

2012-07-16T23:59:59.000Z

362

Aerosol-Cloud interactions : a new perspective in precipitation enhancement  

E-Print Network [OSTI]

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 ...

Gunturu, Udaya Bhaskar

2010-01-01T23:59:59.000Z

363

Atmospheric Aerosol Chemistry, Climate Change, and Air Quality  

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

607 Atmospheric Aerosol Chemistry, Climate Change, and Air Quality An EMSL Science Theme Advisory Panel Workshop Workshop Date: January 30, 2013 Prepared for the U.S. Department of...

364

ARM - Field Campaign - Shortwave Radiation and Aerosol Intensive  

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

govCampaignsShortwave Radiation and Aerosol Intensive Observation govCampaignsShortwave Radiation and Aerosol Intensive Observation Periods Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Shortwave Radiation and Aerosol Intensive Observation Periods 1998.08.03 - 1998.08.28 Lead Scientist : Warren Wiscombe For data sets, see below. Summary Wednesday, August 5, 1998: IOP Opening Activities: The IOP updates for the Shortwave/Aerosol/BDRF will be composed from notes taken during briefing sessions lead by Don Cahoon and company each night at the Marland Mansion in Ponca City. IOP Status as of 8/4/98 Weather forecasts indicate that cloudy conditions will prevail for the next few days. The Helicopter is on standby for clear sky conditions. Model output indicates clear sky's may move in later this week.

365

Research Highlight  

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

Climatology of Aerosol Optical Depth in North-Central Oklahoma: Climatology of Aerosol Optical Depth in North-Central Oklahoma: 1992-2008 Download a printable PDF Submitter: Michalsky, J. J., DOC/NOAA/OAR/ESRL Area of Research: Aerosol Properties Working Group(s): Aerosol Life Cycle Journal Reference: Michalsky J, F Denn, C Flynn, G Hodges, P Kiedron, A Koontz, J Schlemmer, and SE Schwartz. 2010. "Climatology of aerosol optical depth in north-central Oklahoma: 1992-2008." Journal of Geophysical Research - Atmospheres, 115, D07203, doi: 10.1029/2009JD012197. Box plots of each complete year\'s daily averaged aerosol optical depth (AOD) at 500 nm. The dark horizontal line in each box plot is the median daily averaged AOD for the year; the top and bottom of the rectangular box spans the middle 50% of the data. The mean values for the year are plotted

366

Climate impacts of carbonaceous and other non-sulfate aerosols: A proposed study  

SciTech Connect (OSTI)

In addition to sulfate aerosols, carbonaceous and other non-sulfate aerosols are potentially significant contributors to global climate change. We present evidence that strongly suggests that current assessments of the effects of aerosols on climate may be inadequate because major aerosol components, especially carbonaceous aerosols, are not included in these assessments. Although data on the properties and distributions of anthropogenic carbonaceous aerosols are insufficient to allow quantification of their climate impacts, the existing information suggests that climate forcing by this aerosol component may be significant and comparable to that by sulfate aerosols. We propose that a research program be undertaken to support a quantitative assessment of the role in climate forcing of non-sulfate, particularly carbonaceous, aerosols.

Andreae, M.O.; Crutzen, P.J. [Max Planck Institute for Chemistry, Mainz (Germany); Cofer, W.R. III; Hollande, J.M. [NASA Langley Research Center, Hampton, VA (United States). Atmospheric Sciences Division] [and others

1995-06-01T23:59:59.000Z

367

A Numerical Sensitivity Study of Aerosol Influence on Immersion Freezing  

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

Numerical Sensitivity Study of Aerosol Influence on Immersion Freezing Numerical Sensitivity Study of Aerosol Influence on Immersion Freezing in Mixed-Phase Stratiform Clouds Gijs de Boer, Tempei Hashino, Edwin W. Eloranta and Gregory J. Tripoli The University of Wisconsin - Madison (1) Introduction (1) Introduction Mixed-phase stratiform clouds are commonly observed at high latitudes (Shupe et al., 2006; de Boer et al., 2009a). These clouds significaly impact the atmospheric radiative

368

Representing Cloud Processing of Aerosol in Numerical Models  

SciTech Connect (OSTI)

The satellite imagery in Figure 1 provides dramatic examples of how aerosol influences the cloud field. Aerosol from ship exhaust can serve as nucleation centers in otherwise cloud-free regions, forming ship tracks (top image), or can enhance the reflectance/albedo in already cloudy regions. This image is a demonstration of the first indirect effect, in which changes in aerosol modulate cloud droplet radius and concentration, which influences albedo. It is thought that, through the effects it has on precipitation (drizzle), aerosol can also affect the structure and persistence of planetary boundary layer (PBL) clouds. Regions of cellular convection, or open pockets of cloudiness (bottom image) are thought to be remnants of strongly drizzling PBL clouds. Pockets of Open Cloudiness (POCs) (Stevens et al. 2005) or Albrecht's ''rifts'' are low cloud fraction regions characterized by anomalously low aerosol concentrations, implying they result from precipitation. These features may in fact be a demonstration of the second indirect effect. To accurately represent these clouds in numerical models, we have to treat the coupled cloud-aerosol system. We present the following series of mesoscale and large eddy simulation (LES) experiments to evaluate the important aspects of treating the coupled cloud-aerosol problem. 1. Drizzling and nondrizzling simulations demonstrate the effect of drizzle on a mesoscale forecast off the California coast. 2. LES experiments with explicit (bin) microphysics gauge the relative importance of the shape of the aerosol spectrum on the 3D dynamics and cloud structure. 3. Idealized mesoscale model simulations evaluate the relative roles of various processes, sources, and sinks.

Mechem, D.B.; Kogan, Y.L.

2005-03-18T23:59:59.000Z

369

Non-intrusive characterization of heat transfer fluid aerosol formation  

E-Print Network [OSTI]

providing an ignition source for the fine aerosol droplets. TI&e Malvern Laser Diffraction Particle Analyzer RING DIODE ARRAY DETECTOR BEAM EXPANDER/ SPATIAL FILTER HE- NE LASER FOURIER TRANSFORM LENS Figure II-Z. Diffraction particle analyzer... providing an ignition source for the fine aerosol droplets. TI&e Malvern Laser Diffraction Particle Analyzer RING DIODE ARRAY DETECTOR BEAM EXPANDER/ SPATIAL FILTER HE- NE LASER FOURIER TRANSFORM LENS Figure II-Z. Diffraction particle analyzer...

Krishna, Kiran

2012-06-07T23:59:59.000Z

370

Optical Expanders with Applications in Optical Computing  

E-Print Network [OSTI]

Optical Expanders with Applications in Optical Computing John H. Reif \\Lambda Akitoshi Yoshida \\Lambda July 20, 1999 Abstract We describe and investigate an optical system which we call an optical expander. An optical expander elec­ trooptically expands an optical boolean pattern encoded in d bits

Reif, John H.

371

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

SciTech Connect (OSTI)

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

Meskhidze, Nicholas; Zhang, Yang; Kamykowski, Daniel

2012-03-28T23:59:59.000Z

372

On modification of global warming by sulfate aerosols  

SciTech Connect (OSTI)

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.

Mitchell, J.F.B.; Johns, T.C. [Hadley Centre for Climate Prediction and Research, Berkshire (United Kingdom)] [Hadley Centre for Climate Prediction and Research, Berkshire (United Kingdom)

1997-02-01T23:59:59.000Z

373

Characterisation and dissolution of depleted uranium aerosols produced during impacts of kinetic energy penetrators against a tank  

Science Journals Connector (OSTI)

......Characterisation and dissolution of depleted uranium aerosols produced during impacts...Aerosols produced during impacts of depleted uranium (DU) penetrators against the...Characterisation and dissolution of depleted uranium aerosols produced during impacts......

V. Chazel; P. Gerasimo; V. Debouis; P. Laroche; F. Paquet

2003-07-01T23:59:59.000Z

374

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

SciTech Connect (OSTI)

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.

Worsnop, Douglas R. [Principal Investigator

2014-07-28T23:59:59.000Z

375

An Aerosol Condensation Model for Sulfur Trioxide  

SciTech Connect (OSTI)

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

Grant, K E

2008-02-07T23:59:59.000Z

376

Measuring depth profiles of residual stress with Raman spectroscopy  

SciTech Connect (OSTI)

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.

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

1988-12-01T23:59:59.000Z

377

Cone Depth and the Center Vertex Theorem Gary L. Miller Todd Phillips Don Sheehy  

E-Print Network [OSTI]

Abstract We generalize the Tukey depth to use cones instead of halfspaces. We prove a generalization of the most enduring definitions of data depth is the Tukey depth, also known as the half-space depth. The Tukey depth of a point p relative to a point set S is defined as the minimum number of points on one

Miller, Gary L.

378

Direct measurements of marine aerosols to examine the influence of biological activity, anthropogenic emissions, and secondary processing on particle chemistry  

E-Print Network [OSTI]

from a low-speed marine diesel engine, Aerosol Sci. Tech. ,from a low-speed marine diesel engine, Aerosol Sci. Tech. ,

Gaston, Cassandra Jayne

2012-01-01T23:59:59.000Z

379

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

SciTech Connect (OSTI)

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.

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.

2006-10-01T23:59:59.000Z

380

Testing and Performance of Two-Dimensional Optical Array Spectrometers with Greyscale  

Science Journals Connector (OSTI)

Two laboratory optical array spectrometers with greyscale were evaluated for their sizing, depth of field and timing performance; these three factors are necessary to calculate concentrations and liquid water contents. The probes were of 10 and ...

Paul Joe; Roland List

1987-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Gulf of Mexico Proved Reserves By Water Depth, 2009  

U.S. Energy Information Administration (EIA) Indexed Site

Gulf of Mexico Proved Reserves and Production by Water Depth, 2009 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 Fed) has long been one of the Nation's principal sources of proved reserves. At the end of 2009, the GOM Fed accounted for close to one-fifth of oil proved reserves (second only to Texas) and just over four percent of natural gas proved reserves (the country's seventh largest reporting region). 1 Natural gas proved reserves from the GOM Fed have gradually diminished, both volumetrically and as a percentage of overall U.S. proved reserves. The latter is especially true in recent years as onshore additions (particularly those associated with shale gas activity) have increased considerably. Proved oil reserves from

382

Heat Flow At Standard Depth | Open Energy Information  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Heat Flow At Standard Depth Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Heat Flow At Standard Depth Details Activities (2) Areas (1) Regions (0) Abstract: Secular and long-term periodic changes in surface temperature cause perturbations to the geothermal gradient which may be significant to depths of at least 1000 m, and major corrections are required to determine absolute values of heat flow from the Earth's interior. However, detailed climatic models remain contentious and estimates of error in geothermal gradients differ widely. Consequently, regions of anomalous heat flow which

383

Penetration depth scaling for impact into wet granular packings  

E-Print Network [OSTI]

We present experimental measurements of penetration depths for the impact of spheres into wetted granular media. We observe that the penetration depth in the liquid saturated case scales with projectile density, size, and drop height in a fashion consistent with the scaling observed in the dry case, but that penetration depths into saturated packings tend to be smaller. This result suggests that, for the range of impact energies observed, the stopping force is set by static contact forces between grains within the bed, and that the presence of liquid serves, primarily, to enhance these contact forces. The enhancement to the stopping force has a complicated dependence on liquid fraction, accompanied by a change in the drop-height dependence, that must be the consequence of accompanying changes in the conformation of the liquid phase in the interstices.

Theodore A. Brzinski III; Jorin Schug; Kelly Mao; Douglas J. Durian

2015-01-25T23:59:59.000Z

384

Optical memory  

DOE Patents [OSTI]

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.

Mao, Samuel S; Zhang, Yanfeng

2013-07-02T23:59:59.000Z

385

ARM - VAP Process - aod  

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

Productsaod Productsaod Documentation & Plots Technical Report (1) Technical Report (2) Data Management Facility Plots (Quick Looks) ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send VAP : Aerosol Optical Depth (AOD) Instrument Categories Derived Quantities and Models The core purpose of the ARM Facility is to reduce uncertainties in climate model predictions. A dominant source of uncertainty in these models is the radiative impact of aerosols, which has spawned a major effort in ARM to measure aerosol properties. The Aerosol Optical Depth (AOD) value-added product (VAP) is concerned with several important aerosol radiative properties. The most important of these is the aerosol optical depth (AOD), which is a measure of the total aerosol

386

Depth of Interaction Enhanced Gamma-Ray Imaging for Medical Applications  

E-Print Network [OSTI]

A novel design for an inexpensive depth of interaction capable detector for gamma rays, suitable for nuclear medical applications, especially Positron Emission Tomography, has been developed. The design takes advantage of the strong correlation between the width of the scintillation light distribution in continuous crystals and the depth of interaction of the gamma-ray. For measuring the distribution width, an inexpensive modification of the commonly used charge dividing circuits that allows analogue and instantaneous computation of the 2nd moment has been developed and is presented in this work. The method has been tested with a detector made of a continuous LSO-scintillator of dimensions 42x42x10 cubic mm and optically coupled to the compact large area position sensitive photomultiplier H8500 from Hamamatsu. The mean resolution in all non-trivial moments was found to be smaller than 5% but their direct use as estimates for the three-dimensional photoconversion position turned out to be unsuitable. Standard polynomial interpolation in higher dimensions has been adopted to reconstruct the impact positions of the gamma-rays from the measured moments. When using the reconstructed impact positions, the intrinsic mean spatial resolution of the detector was found to be 1.9 mm for the transverse components and 3.9 mm for the depth of interaction. Using directly the bare moments as position estimate, the intrinsic mean spatial resolution of the detector was found to be 3.4 mm and 4.9 mm, respectively. The cost for the required detector improvements are essentially negligible.

Christoph W. Lerche

2006-11-01T23:59:59.000Z

387

E-Print Network 3.0 - aerosols apports du Sample Search Results  

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

Summary: Regional Impact of Inter-Continental Aerosol Transport Leona Charles*a,b , Barry Grossa, Fred... to study the interaction of aerosols in the PBL with long range...

388

Organic Aerosol Formation from Photochemical Oxidation of Diesel Exhaust in a Smog Chamber  

Science Journals Connector (OSTI)

Diluted exhaust from a diesel engine was photo-oxidized in a smog chamber to investigate secondary organic aerosol (SOA) production. Photochemical aging rapidly produces significant SOA, almost doubling the organic aerosol contribution of primary ...

Emily A. Weitkamp; Amy M. Sage; Jeffrey R. Pierce; Neil M. Donahue; Allen L. Robinson

2007-09-11T23:59:59.000Z

389

Comparison of Carbonaceous Aerosols in Tokyo before and after Implementation of Diesel Exhaust Restrictions  

Science Journals Connector (OSTI)

Comparison of Carbonaceous Aerosols in Tokyo before and after Implementation of Diesel Exhaust Restrictions ... (5)?Albert, R. E. Comparative carcinogenic potencies of particulates from diesel engine exhausts, coke oven emissions, roofing tar aerosols and cigarette smoke. ...

Naomichi Yamamoto; Atsushi Muramoto; Jun Yoshinaga; Ken Shibata; Michio Endo; Osamu Endo; Motohiro Hirabayashi; Kiyoshi Tanabe; Sumio Goto; Minoru Yoneda; Yasuyuki Shibata

2007-08-15T23:59:59.000Z

390

E-Print Network 3.0 - aerosol lidar profilometer Sample Search...  

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

CLASIC Summary: Lidar RH Changes in aerosol properties and RH near clouds Airborne NASA LaRC HSRL, ARM SGP ground... ) RamanLidar RelativeHumidityRamanLidar Aerosol Extensive...

391

The Evolution of the Physicochemical Properties of Aerosols in the Atmosphere  

E-Print Network [OSTI]

campaign investigated the evolution of the physicochemical properties of the Asian aerosol plume after 3 to 7 days of transport. The Asian aerosol within the free troposphere exhibited a bimodal growth distribution roughly 50 percent of the time. The more...

Tomlinson, Jason

2011-02-22T23:59:59.000Z

392

Aerodynamic Focusing of High-Density Aerosols D.E. Ruiza,  

E-Print Network [OSTI]

Aerodynamic Focusing of High-Density Aerosols D.E. Ruiza, , L. Gundersona , M.J. Haya , E. Merinob-density aerosol focusing for 1µm silica spheres. Preliminary results recover previous findings on aerodynamic

393

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

E-Print Network [OSTI]

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 ...

Jeong, Gill-Ran

394

E-Print Network 3.0 - aerosolized red tide Sample Search Results  

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

characteristics of desert dust and biomass burning aerosols Summary: in the right panel of Fig. 6. The aerosol scenes spectra are drawn in green, the clear sky scenes in...

395

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

E-Print Network [OSTI]

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. ...

Rosenfeld, Daniel

396

Estimating the lung burden from exposure to aerosols of depleted uranium  

Science Journals Connector (OSTI)

......from exposure to aerosols of depleted uranium Marcelo Valdes * * Corresponding...Following exposure to aerosols of depleted uranium (DU), biological samples...uranyl phosphates. INTRODUCTION Depleted uranium (DU) is a waste product of......

Marcelo Valds

2009-02-01T23:59:59.000Z

397

Elucidating secondary organic aerosol from diesel and gasoline vehicles through detailed characterization of  

E-Print Network [OSTI]

Elucidating secondary organic aerosol from diesel and gasoline vehicles through detailed 19, 2012 (received for review July 22, 2012) Emissions from gasoline and diesel vehicles composition, mass distribu- tion, and organic aerosol formation potential of emissions from gasoline

Silver, Whendee

398

Investigation of the aerosol-cloud interaction using the WRF framework  

E-Print Network [OSTI]

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 of cloud properties...

Li, Guohui

2009-05-15T23:59:59.000Z

399

E-Print Network 3.0 - aerosol flame deposition Sample Search...  

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

search results for: aerosol flame deposition Page: << < 1 2 3 4 5 > >> 1 Flame aerosol nano-technology has been developed to preparation of thin and defect-free porous membrane...

400

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

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

The Sensitivity of a Numerically Simulated Idealized Squall Line to the Vertical Distribution of Aerosols  

Science Journals Connector (OSTI)

Changes in the aerosol number concentration are reflected by changes in raindrop size and number concentration that ultimately affect the strength of cold pools via evaporation. Therefore, aerosol perturbations can potentially alter the balance ...

Zachary J. Lebo

2014-12-01T23:59:59.000Z

402

An Investigation of Hydrogen Depth Profiling Using ToF-SIMS....  

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

Investigation of Hydrogen Depth Profiling Using ToF-SIMS. An Investigation of Hydrogen Depth Profiling Using ToF-SIMS. Abstract: Hydrogen depth distributions in silicon, zinc oxide...

403

X-ray microlaminography with polycapillary optics K. M. Dbrowski, D. T. Dul, A. Wrbel, and P. Korecki  

E-Print Network [OSTI]

X-ray microlaminography with polycapillary optics K. M. Dbrowski, D. T. Dul, A. Wróbel, and P://apl.aip.org/features/most_downloaded Information for Authors: http://apl.aip.org/authors #12;X-ray microlaminography with polycapillary optics K. M demonstrate layer-by-layer x-ray microimaging using polycapillary optics. The depth resolution is achieved

Korecki, Pawe³

404

Aerosol Data Sources and Their Roles within PARAGON  

SciTech Connect (OSTI)

We briefly but systematically review major sources of aerosol data, emphasizing suites of measurements that seem most likely to contribute to assessments of global aerosol climate forcing. The strengths and limitations of existing satellite, surface, and aircraft remote-sensing systems are described, along with those of direct sampling networks and ship-based stations. It is evident that an enormous number of aerosol-related observations have been made, on a wide range of spatial and temporal sampling scales, and that many of the key gaps in this collection of data could be filled by technologies that either exist or are expected in the near future. Emphasis must be given to combining remote sensing, in situ, active and passive observations, and integrating them with aerosol chemical transport models, in order to create a more complete environmental picture having sufficient detail to address current climate-forcing questions. The Progressive Aerosol Retrieval and Assimilation Global Observing Network (PARAGON) initiative would provide an organizational framework to meet this goal.

Kahn, Ralph A.; Ogren, J. A.; Ackerman, Thomas P.; Bosenberg, Jens; Charlson, Robert J.; Diner, David J.; Holben, B. N.; Menzies, Robert T.; Miller, Mark A.; Seinfeld, John H.

2004-10-01T23:59:59.000Z

405

Calculating Capstone Depleted Uranium Aerosol Concentrations from Beta Activity Measurements  

SciTech Connect (OSTI)

Beta activity measurements were used as surrogate measurements of uranium mass in aerosol samples collected during the field testing phase of the Capstone Depleted Uranium (DU) Aerosol Study. These aerosol samples generated by the perforation of armored combat vehicles were used to characterize the depleted uranium (DU) source term for the subsequent human health risk assessment (HHRA) of Capstone aerosols. Establishing a calibration curve between beta activity measurements and uranium mass measurements is straightforward if the uranium isotopes are in equilibrium with their immediate short-lived, beta-emitting progeny. For DU samples collected during the Capstone study, it was determined that the equilibrium between the uranium isotopes and their immediate short lived, beta-emitting progeny had been disrupted when penetrators had perforated target vehicles. Adjustments were made to account for the disrupted equilibrium and for wall losses in the aerosol samplers. Correction factors for the disrupted equilibrium ranged from 0.16 to 1, and the wall loss correction factors ranged from 1 to 1.92.

Szrom, Fran; Falo, Gerald A.; Parkhurst, MaryAnn; Whicker, Jeffrey J.; Alberth, David P.

2009-03-01T23:59:59.000Z

406

Secondary Aerosol: Precursors and Formation Mechanisms. Technical Report on Grant  

SciTech Connect (OSTI)

This project focused on studying trace gases that participate in chemical reactions that form atmospheric aerosols. Ammonium sulfate is a major constituent of these tiny particles, and one important pathway to sulfate formation is oxidation of dissolved sulfur dioxide by hydrogen peroxide in cloud, fog and rainwater. Sulfate aerosols influence the number and size of cloud droplets, and since these factors determine cloud radiative properties, sulfate aerosols also influence climate. Peroxide measurements, in conjunction with those of other gaseous species, can used to distinguish the contribution of in-cloud reaction to new sulfate aerosol formation from gas-phase nucleation reactions. This will lead to more reliable global climate models. We constructed and tested a new 4-channel fluorescence detector for airborne detection of peroxides. We integrated the instrument on the G-1 in January, 2006 and took a test flight in anticipation of the MAX-Mex field program, where we planned to fly under pressurized conditions for the first time. We participated in the 2006 Megacity Initiative: Local and Global Research Observations (MILAGRO) - Megacity Aerosol EXperiment ?? Mexico City (MAX-Mex) field measurement campaign. Peroxide instrumentation was deployed on the DOE G-1 research aircraft based in Veracruz, and at the surface site at Tecamac University.

Weinstein-Lloyd, Judith B

2009-05-04T23:59:59.000Z

407

E-Print Network 3.0 - arctic aerosol burden Sample Search Results  

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

and surface... generally exhibits low aerosol ... Source: National Oceanic and Atmospheric Administration, Pacific Marine Environmental Laboratory, Atmopsheric Chemistry and...

408

E-Print Network 3.0 - aerosol biokinetics concentrations Sample...  

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

October 4, 2004 Abstract Atmospheric aerosol particles scatter and absorb shortwave (solar) radiation and Source: Brookhaven National Laboratory, Environmental Chemistry...

409

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.

410

Does footprint depth correlate with foot motion and pressure?  

Science Journals Connector (OSTI)

...correlations found across the foot by Hatala et al. [11], D'Aout...and in the heel and mid-foot, when depth was compared with...difference in the predictive power of peak pressure and the PT...applied by the trackmaker's foot during print formation is the...

2013-01-01T23:59:59.000Z

411

Continuous Snow Depth, Intensive Site 1, Barrow, Alaska  

SciTech Connect (OSTI)

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.

Cable, William; Romanovsky, Vladimir; Hinzman, Larry; Busey, Bob

2014-11-06T23:59:59.000Z

412

Steady periodic waves bifurcating for fixed-depth rotational flows  

E-Print Network [OSTI]

-current interactions [29, 37] or flows generated by wind-shear [30] (see [6] for a comprehensive discussion than the mass-flux. It is important to note that fixing the mass-flux p0 does not fix the depth d

413

Human Activities Recognition with RGB-Depth Camera using HMM  

E-Print Network [OSTI]

. In this paper, we propose a method to detect fall using a system made up of RGB-Depth cameras. The major benefit. An evaluation has been conducted within a real smart environment with 26 subjects which were performing any]), Gaussian Mixture Model [6], least median of squares [1], occupancy grid [5]. Then the second stage

Paris-Sud XI, Université de

414

Parameterised structured light imaging for depth edge detection  

E-Print Network [OSTI]

, [amin, amax], from the projector/camera', `width of horizontal stripes, w', and `minimum detectable depth difference, rmin'. As can be seen in Fig. 1a, amax and rmin are given as the input parameters of [amin, amax] are guaranteed to be detected. However, awkwardly enough, amin is found at a later step

California at Santa Barbara, University of

415

WaveCurrent Interactions in Finite Depth JEROME A. SMITH  

E-Print Network [OSTI]

Wave­Current Interactions in Finite Depth JEROME A. SMITH Scripps Institution of Oceanography, La (Longuet-Higgins 1969; Hasselmann 1971; Garrett and Smith 1976; and many others). In particular, Hassel) changes in wave momentum that absorb some of the radiation stress gradients. Garrett and Smith (1976

Smith, Jerome A.

416

Wave-current interaction in water of finite depth  

E-Print Network [OSTI]

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 ...

Huang, Zhenhua, 1967-

2004-01-01T23:59:59.000Z

417

Continuous Snow Depth, Intensive Site 1, Barrow, Alaska  

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

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.

Cable, William; Romanovsky, Vladimir; Hinzman, Larry; Busey, Bob

418

BNL-65388-AB PROPERTIES OF AMMONIATED SULFATE AEROSOLS AT LOW TEMPERATURES  

E-Print Network [OSTI]

BNL-65388-AB PROPERTIES OF AMMONIATED SULFATE AEROSOLS AT LOW TEMPERATURES: WHY ARE THE MODELS SO of Energy under Contract No. DE-AC02-98CH10886. #12;PROPERTIES OF AMMONIATED SULFATE AEROSOLS AT LOW will present a study of the properties of ammoniated sulfate aerosols ((NH4)2SO4, NH4HSO4, and in- between

419

REPRESENTING AEROSOL DYNAMICS AND PROPERTIES IN CHEMICAL TRANSPORT MODELS BY THE METHOD OF MOMENTS  

E-Print Network [OSTI]

understanding of the key processes that govern the aerosol size distribution: · Gas-to-particle conversion--conversion, suspensions of solid or liquid particles, are an important multi- phase system. Aerosols scatter and absorb retrospectively and prospectively for different emissions scenarios. Important aerosol properties and processes

420

Cloud and Aerosol Properties, Precipitable Water, and Profiles of Temperature and Water Vapor from MODIS  

E-Print Network [OSTI]

Cloud and Aerosol Properties, Precipitable Water, and Profiles of Temperature and Water Vapor from such as cloud mask, atmos- pheric profiles, aerosol properties, total precipitable water, and cloud properties vapor amount, aerosol particles, and the subsequently formed clouds [9]. Barnes et al. [2] provide

Sheridan, Jennifer

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Surface based remote sensing of aerosol-cloud interactions  

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

Surface based remote sensing of aerosol-cloud interactions Surface based remote sensing of aerosol-cloud interactions Feingold, Graham NOAA/Environmental Technology Laboratory Frisch, Shelby NOAA/Environmental Technology Laboratory Min, Qilong State University of New York at Albany Category: Cloud Properties We will present an analysis of the effect of aerosol on clouds at the Southern Great Plains ARM site. New methods for retrieving cloud droplet effective radius with radar (MMCR), multifilter rotating shadowband radiometer (MFRSR), and microwave radiometer (MWR) will be discussed. Relationships based on adiabatic clouds will be used to constrain retrievals. We will investigate the use of a range of proxies for cloud condensation nuclei, ranging from surface measurements of light scattering and accumulation mode number concentration, to lidar-measured extinction or

422

ARM - Publications: Science Team Meeting Documents: Effects of Aerosol Size  

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

Effects of Aerosol Size Distribution and Vertical Profile on the Effects of Aerosol Size Distribution and Vertical Profile on the Polarization in the Oxygen A-Band Duan, Minzheng State University of New York at Albany Min, Qilong State University of New York at Albany A vector radiative transfer code with successive order of scattering method was used to simulate the high-resolution polarization spectra in the oxygen A-band. The effects of aerosol size distribution and vertical profile on the radiance and polarization at the top and bottom of the atmosphere were analyzed. The impacts of instrument specification on information content are also analyzed. Polarized radiances were dominated (>95%) by the first and second orders of scattering. The contributions of scattering from different levels to the TOA and surface observation are analyzed. The

423

Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Particles  

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

2414 2414 1 Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Particles M. P. Modera, O. Brzozowski ** , F. R. Carrié * , D. J. Dickerhoff, W. W. Delp, W. J. Fisk, R. Levinson, D. Wang Abstract Electricity energy savings potential by eliminating air leakage from ducts in large commercial buildings is on the order of 10 kWh/m 2 per year (1 kWh/ft 2 ). We have tested, in two large commercial buildings, a new technology that simultaneously seals duct leaks and measures effective leakage area of ducts. The technology is based upon injecting a fog of aerosolized sealant particles into a pressurized duct system. In brief, this process involves blocking all of the intentional openings in a duct system (e.g., diffusers). Therefore, when the system is pressurized, the only place for the air carrying the aerosol

424

Direct Aerosol Forcing in the Infrared at the SGP Site?  

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

Direct Aerosol Forcing in the Infrared at the SGP Site? Direct Aerosol Forcing in the Infrared at the SGP Site? D. D. Turner and C. N. Long Pacific Northwest National Laboratory Richland, Washington Introduction Low level haze is often observed during the night and early morning hours in many locations. This haze is typically formed during quiescent conditions by radiative cooling of the surface, which lowers the ambient temperature and consequently increases the near-surface relative humidity (RH). Many aerosols start to deliquesce around 75% relative humidity (RH) (depending on their chemical composition), and thus if the near surface RH increases above this level, haze will form. The Atmospheric Radiation Measurement (ARM) Program's ultimate goal, stated simply, is to improve the treatment of radiative transfer in global climate models. Global climate models typically do not

425

ARM - Field Campaign - Ganges Valley Aerosol Experiment (GVAX)  

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

govCampaignsGanges Valley Aerosol Experiment (GVAX) govCampaignsGanges Valley Aerosol Experiment (GVAX) Campaign Links Science Plan AMF India Deployment Website Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Ganges Valley Aerosol Experiment (GVAX) 2011.06.13 - 2012.03.31 Website : http://www.arm.gov/sites/amf/pgh/ Lead Scientist : V. Rao Kotamarthi Description 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 monsoon. Impacts of changes in precipitation patterns, temperature, and the flow of the snow-fed rivers could be immense. Recent satellite-based measurements have indicated that

426

Lognormal Size Distribution Theory for Deposition of Polydisperse Aerosol Particles  

SciTech Connect (OSTI)

The moments method of the lognormal size distribution theory was applied to the deposition equation of a radioactive aerosol within a liquid-metal fast breeder reactor for analysis of postulated accidents. The deposition coefficient of Crump and Seinfeld was utilized to represent the Brownian and turbulent diffusions and the gravitational sedimentation. The deposition equation was converted into a set of three ordinary differential equations. This approach takes the view point that the size distribution of an aerosol is represented by a time-dependent lognormal size distribution function during the deposition process. Numerical calculations have been performed, and the results were found to be in good agreement with the exact solution. The derived model for aerosol deposition is convenient to use in a numerical general dynamic equation solution routine based on the moments method, where nucleation, condensation, coagulation, and deposition need to be solved simultaneously.

Park, S.H.; Lee, K.W. [Kwangju Institute of Science and Technology (Korea, Republic of)

2000-07-15T23:59:59.000Z

427

Aerosols and Clouds: In Cahoots to Change Climate  

ScienceCinema (OSTI)

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."

Berg, Larry

2014-06-02T23:59:59.000Z

428

Distinguishing Aerosol Impacts on Climate Over the Past Century  

SciTech Connect (OSTI)

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.

Koch, Dorothy; Menon, Surabi; Del Genio, Anthony; Ruedy, Reto; Alienov, Igor; Schmidt, Gavin A.

2008-08-22T23:59:59.000Z

429

On surface temperature, greenhouse gases, and aerosols: models and observations  

SciTech Connect (OSTI)

The effect of changes in atmospheric carbon dioxide concentrations and sulphate aerosols on near-surface temperature is investigated using a version of the Hadley Centre atmospheric model coupled to a mixed layer ocean. The scattering of sunlight by sulphate aerosols is represented by appropriately enhancing the surface albedo. On doubling atmospheric carbon dioxide concentrations, the global mean temperature increases by 5.2 K. An integration with a 39% increase in CO{sub 2}, giving the estimated change in radiative heating due to increases in greenhouse gases since 1900, produced an equilibrium warming of 2.3 K, which, even allowing for oceanic inertia, is significantly higher than the observed warming over the same period. Furthermore, the simulation suggests a substantial warming everywhere, whereas the observations indicate isolated regions of cooling, including parts of the northern midlatitude continents. The addition of an estimate of the effect of scattering by current industrial aerosols (uncertain by a factor of at least 3) leads to improved agreement with the observed pattern of changes over the northern continents and reduces the global mean warming by about 30%. Doubling the aerosol forcing produces patterns that are still compatible with the observations, but further increase leads to unrealistically extensive cooling in the midlatitudes. The diurnal range of surface temperature decreases over most of the northern extratropics on increasing CO{sub 2}, in agreement with recent observations. The addition of the current industrial aerosol had little detectable effect on the diurnal range in the model because the direct effect of reduced solar heating at the surface is approximately balanced by the indirect effects of cooling. Thus, the ratio of the reduction in diurnal range to the mean warming is increased, in closer agreement with observations. Results from further sensitivity experiments with larger increases in aerosol and CO{sub 2} are presented.

Mitchell, J.F.B.; Davis, R.A.; Ingram, W.J.; Senior, C.A. [Hadley Centre for Climate Prediction and Research, Berkshire (United Kingdom)] [Hadley Centre for Climate Prediction and Research, Berkshire (United Kingdom)

1995-10-01T23:59:59.000Z

430

Optics and Diagnostics  

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

2 14 | Next | Last Back to Index Optics Line up of optics after cleaning. Photo Number: 2013-048779...

431

Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant  

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

Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Particles Title Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Particles Publication Type Journal Article LBNL Report Number LBNL-42414 Year of Publication 2001 Authors Modera, Mark P., Olivier Brzozowski, François Rémi Carrié, Darryl J. Dickerhoff, William W. Delp, William J. Fisk, Ronnen M. Levinson, and Duo Wang Journal Energy & Buildings Volume 34 Start Page Chapter Pagination 705-714 Abstract Electricity energy savings potential by eliminating air leakage from ducts in large commercial buildings is on the order of 10 kWh/m2 per year (1 kWh/ft2). We have tested, in two large commercial buildings, a new technology that simultaneously seals duct leaks and measures effective leakage area of ducts. The technology is based upon injecting a fog of aerosolized sealant particles into a pressurized duct system. In brief, this process involves blocking all of the intentional openings in a duct system (e.g., diffusers). Therefore, when the system is pressurized, the only place for the air carrying the aerosol particles to exit the system is through the leaks. The key to the technology is to keep the particles suspended within the airstream until they reach the leaks, and then to have them leave the airstream and deposit on the leak sites. The principal finding from this field study was that the aerosol technology is capable of sealing the leaks in a large commercial building duct system within a reasonable time frame. In the first building, 66% of the leakage area was sealed within 2.5 hours of injection, and in the second building 86% of the leakage area was sealed within 5 hours. We also found that the aerosol could be blown through the VAV boxes in the second building without impacting their calibrations or performance. Some remaining questions are (1) how to achieve sealing rates comparable to those experienced in smaller residential systems; and (2) what tightness level these ducts systems can be brought to by means of aerosol sealing.

432

Thermophoretic separation of aerosol particles from a sampled gas stream  

DOE Patents [OSTI]

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.

Postma, Arlin K. (Halfway, OR)

1986-01-01T23:59:59.000Z

433

Final Project Report - ARM CLASIC CIRPAS Twin Otter Aerosol  

SciTech Connect (OSTI)

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.

John A. Ogren

2010-04-05T23:59:59.000Z

434

Flattening coefficient of aerosols collected on treated slides  

E-Print Network [OSTI]

collected from oleic acid and DOP (dioctylphthalate) aerosols, The microscope slides were made oilphobic by immersion in a widely used fluorocarbon sur- factant (NYE BAR Type CT 2X or 3' Co. Chemical FC-721). The mean value of F f' or oleic acid... 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...

Olan-Figueroa, Excel

2012-06-07T23:59:59.000Z

435

Thermophoretic separation of aerosol particles from a sampled gas stream  

DOE Patents [OSTI]

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.

Postma, A.K.

1984-09-07T23:59:59.000Z

436

Parallel optical sampler  

SciTech Connect (OSTI)

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.

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

2014-05-20T23:59:59.000Z

437

Drilling/producing depths; Two records and a revision  

SciTech Connect (OSTI)

This paper reports that record depths for natural gas or oil well drilling or producing continue to be rare occurrences, although one or two still come in each year. Records fell in Texas Railroad Commission (RRC) District 9 and in the California area of the Minerals Management Service (MMS) Pacific Outer Continental Shelf (OCS) in 1990. Deep drilling and production has traditionally been defined as well depths greater than 15,000 ft. Smith Tool reported that 9.4% of all active rotary rigs were dedicated to targets below 15,000 ft at the beginning of 1991. Deep rigs had dropped to 8.1% by year-end 1991, but remained above the 1989 and 1990 levels of 8.4 and 7.6%, respectively. In 1988 about 11% of active rigs were drilling deep at any given time.

Not Available

1992-02-01T23:59:59.000Z

438

Long-term Statistics of Continental Cumuli: Does Aerosol Trigger Cumulus Variability?  

SciTech Connect (OSTI)

Atmospheric aerosols may control the formation, maintenance, and dissipation of cumuli by changing their microphysics. Recent observational and modeling results exist both in support and against strong potential impacts of aerosol [1-3]. Typically, the aerosol impact on water clouds has been investigated for regions with high aerosol loading and/or large atmospheric moisture [4]. Can we provide observational evidence of the aerosol-cloud relationship for a relatively dry continental region with low/moderate aerosol burden? To address this question, we revisit the aerosol-cloud relationship at the Atmospheric Radiation Measurement (ARM) Climate Research Facility (ACRF) Southern Great Plains (SGP) site. In comparison with highly polluted regions, the SGP site is characterized by relatively small-to-moderate aerosol loading. Also, moisture content is small-to-moderate (compared to marine and coastal regions) for the SGP site. Because cumulus clouds have important impacts on climate forcing estimations [5] and are susceptible to aerosol effects [6], we focus on fair-weather cumuli (FWC) and their association with aerosol concentration and other potentially important factors. This association is investigated using a new 8-year aerosol and cloud climatology (2000-2007) developed with collocated and coincident surface and satellite observations.

Kassianov, Evgueni I.; Berg, Larry K.; McFarlane, Sally A.; Flynn, Connor J.; Turner, David D.

2009-02-01T23:59:59.000Z

439

Joint Depth Estimation and Camera Shake Removal from Single Blurry Image Ming-Hsuan Yang1  

E-Print Network [OSTI]

. While depth information is critical in blur removal, the blur im- age provides an additional cueJoint Depth Estimation and Camera Shake Removal from Single Blurry Image Zhe Hu1 Li Xu2 Ming contain depth information which can be exploited. We propose to jointly estimate scene depth and remove

Yang, Ming-Hsuan

440

An Optimal Randomized Algorithm for Maximum Tukey Depth Timothy M. Chan  

E-Print Network [OSTI]

An Optimal Randomized Algorithm for Maximum Tukey Depth Timothy M. Chan Abstract We present the first optimal algorithm to compute the maximum Tukey depth (also known as location or halfspace depth , the Tukey depth of a point q IRd is defined as: min{|P | : over all halfspaces containing q}. We

Chan, Timothy M.

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Ground-truth aerosol lidar observations: can the Klett solutions obtained from ground and space be equal for the same aerosol case?  

Science Journals Connector (OSTI)

Upcoming multiyear satellite lidar aerosol observations need strong support by a worldwide ground-truth lidar network. In this context the question arises as to whether the ground...

Ansmann, Albert

2006-01-01T23:59:59.000Z

442

Optical Packet Switching -1 Optical Networks  

E-Print Network [OSTI]

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

Mellia, Marco

443

Infrared cloud imaging in support of Earth-space optical communication  

E-Print Network [OSTI]

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

Shaw, Joseph A.

444

Water content and morphology of sodium chloride aerosol particles  

E-Print Network [OSTI]

to explain the H2O content. The model in which the NaCl particles contain pockets of aqueous NaCl solution was found to be most consistent with the spectroscopic observations. The relevance of salt particle morphology and water content to atmospheric aerosol...

Weis, David D.; Ewing, George E.

1999-09-20T23:59:59.000Z

445

HEMISPHERIC-SCALE CHEMICAL AND MICROPHYSICAL AEROSOL MODEL  

E-Print Network [OSTI]

Dignon Bates/Lamb DRY DEPOSITION Wesely WET DEPOSITION Berkowitz/Hales CHEMISTRY Gas Aqueous SO2 + OH [OH dependent Size Resolved Wesely WET DEPOSITION Berkowitz/Hales CHEMISTRY Gas Phase Aqueous Phase SO2 AEROSOL;Anthropogenic Anthropogenic #12;by Production Mechanism Gas phase Aqueous Phase Primary October 15, 1986 at 6 UT

Schwartz, Stephen E.

446

Soft ionization of thermally evaporated hypergolic ionic liquid aerosols  

SciTech Connect (OSTI)

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.

University of California; ERC, Incorporated, Edwards Air Force Base; Air Force Research Laboratory, Edwards Air Force Base; National Synchrotron Radiation Research Center (NSRRC); Koh, Christine J.; Liu, Chen-Lin; Harmon, Christopher W.; Strasser, Daniel; Golan, Amir; Kostko, Oleg; Chambreau, Steven D.; L.Vaghjiani, Ghanshyam; Leone, Stephen R.

2012-03-16T23:59:59.000Z

447

Building America Webinar: Sealing of Home Enclosures with Aerosol Particles  

Broader source: Energy.gov [DOE]

This webinar was presented by research team Building Industry Research Alliance (BIRA), and provided information about a project that uses existing aerosol duct sealing technology to seal the entire building enclosure in order to achieve greater airtightness and energy and cost savings.

448

LESSONS LEARNED IN AEROSOL MONITORING WITH THE RASA  

SciTech Connect (OSTI)

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.

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.

2011-09-14T23:59:59.000Z

449

An overview of geoengineering of climate using stratospheric sulphate aerosols  

Science Journals Connector (OSTI)

...prior to mixing with turbine bypass air, through...and infrastructure development effort needed to...sulphate aerosol strategy is imperfect. The...with greenhouse gases. Furthermore...reductions in greenhouse gas emissions must take...geoengineering mitigation strategy occurring in the...

2008-01-01T23:59:59.000Z

450

CLOUD DROPLET NUCLEATION AND ITS CONNECTION TO AEROSOL PROPERTIES  

E-Print Network [OSTI]

CLOUD DROPLET NUCLEATION AND ITS CONNECTION TO AEROSOL PROPERTIES STEPHEN E. SCHWARTZ Environmental in cloud-free conditions and indirectly, by increasing concentratiol1S of cloud droplets thereby enhancing cloud shortwave reflectivity. These effecls are thought to be significant in the context of changes

451

AT631, Spring 2011 Introduction to Atmospheric Aerosols  

E-Print Network [OSTI]

. Pandis, Atmospheric Chemistry and Physics: From Air Pollution to Climate Change, Wiley-Interscience, 2006AT631, Spring 2011 Introduction to Atmospheric Aerosols Tuesdays 9-9:50 AM, 212B ACRC Wednesdays, Lab, 1-4 PM, ACB 10 Instructor: Prof. Sonia Kreidenweis Atmospheric Chemistry Bldg., Room 19 491

452

Optics and Optical Engineering Program Assessment Plan Program Learning Objectives  

E-Print Network [OSTI]

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

Cantlon, Jessica F.

453

Optical sedimentation recorder  

DOE Patents [OSTI]

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.

Bishop, James K.B.

2014-05-06T23:59:59.000Z

454

Optical microphone  

DOE Patents [OSTI]

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.

Veligdan, James T. (Manorville, NY)

2000-01-11T23:59:59.000Z

455

FY 2011 Second Quarter: Demonstration of New Aerosol Measurement Verification Testbed for Present-Day Global Aerosol Simulations  

SciTech Connect (OSTI)

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 (1020 km) until 510 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).

Koch, D

2011-03-20T23:59:59.000Z

456

Average Depth of Crude Oil and Natural Gas Wells  

Gasoline and Diesel Fuel Update (EIA)

Depth of Crude Oil and Natural Gas Wells Depth of Crude Oil and Natural Gas Wells (Feet per Well) Period: Annual Download Series History Download Series History Definitions, Sources & Notes Definitions, Sources & Notes 2003 2004 2005 2006 2007 2008 View History Exploratory and Development Wells 5,426 5,547 5,508 5,613 6,064 5,964 1949-2008 Crude Oil 4,783 4,829 4,836 4,846 5,111 5,094 1949-2008 Natural Gas 5,616 5,757 5,777 5,961 6,522 6,500 1949-2008 Dry Holes 5,744 5,848 5,405 5,382 5,578 5,540 1949-2008 Exploratory Wells 6,744 6,579 6,272 6,187 6,247 6,322 1949-2008 Crude Oil 6,950 8,136 8,011 7,448 7,537 7,778 1949-2008 Natural Gas 6,589 5,948 5,732 5,770 5,901 5,899 1949-2008 Dry Holes 6,809 6,924 6,437 6,340 6,307 6,232 1949-2008

457

Optical data latch  

DOE Patents [OSTI]

An optical data latch is formed on a substrate from a pair of optical logic gates in a cross-coupled arrangement in which optical waveguides are used to couple an output of each gate to an photodetector input of the other gate. This provides an optical bi-stability which can be used to store a bit of optical information in the latch. Each optical logic gate, which can be an optical NOT gate (i.e. an optical inverter) or an optical NOR gate, includes a waveguide photodetector electrically connected in series with a waveguide electroabsorption modulator. The optical data latch can be formed on a III-V compound semiconductor substrate (e.g. an InP or GaAs substrate) from III-V compound semiconductor layers. A number of optical data latches can be cascaded to form a clocked optical data shift register.

Vawter, G. Allen (Corrales, NM)

2010-08-31T23:59:59.000Z

458

Campbell penetration depth in Fe-based superconductors  

SciTech Connect (OSTI)

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.

Prommapan, Plegchart

2011-08-15T23:59:59.000Z

459

Optics and Diagnostics  

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

1 14 | Next | Last Back to Index Optics Optics processing of Target Wedged Focus Lens into cleaningcoating frame. Photo Number: 2013-048765...

460

Optics and Diagnostics  

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

3 14 | Next | Last Back to Index Optics Alignment Conducting an optics alignment after replacement of a Pockels Cell in the clean room. Photo Number: 2013-050691...

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Optics and Diagnostics  

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

9 14 | Next | Last Back to Index Optics Processing Optics for the National Ignition Facility must be manufactured to exacting standards. To ensure quality, precise measurements...

462

1  

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

Spectral Dependences of the Atmospheric Aerosol Optical Spectral Dependences of the Atmospheric Aerosol Optical Depth in the Extended Spectral Region of 0.4-4 μm S.M. Sakerin and D.M. Kabanov Institute of Atmospheric Optics Tomsk, Russia Introduction Regular measurements of the aerosol optical depth (AOD) in different regions are important for studying the aerosol climate forcing (see Report WMO 2005; Holben 1998). To date, the majority of measurements of AOD - τ А (λ) are carried out in the relatively narrow wavelength range 0.34-1 μm, where the effect of aerosol on the radiative processes is more significant then molecular absorption. To obtain a more accurate definition of the climatic role of atmospheric aerosol, it is necessary to obtain data in different regions and in a wider wavelength range of the incoming radiation. The results in the

463

ARM - Field Campaign - Routine AAF CLOWD Optical Radiative Observations  

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

govCampaignsRoutine AAF CLOWD Optical Radiative Observations (RACORO) govCampaignsRoutine AAF CLOWD Optical Radiative Observations (RACORO) Campaign Links RACORO Website Related Campaigns Surface Radiation Comparison Transfer Measurements for RACORO 2009.01.20, Long, SGP Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Routine AAF CLOWD Optical Radiative Observations (RACORO) 2009.01.22 - 2009.06.30 Website : http://acrf-campaign.arm.gov/racoro/ Lead Scientist : Andrew Vogelmann For data sets, see below. Description The ARM Aerial Facility (AAF) supported the Routine AAF Clouds with Low Optical Water Depths (CLOWD) Optical Radiative Observations (RACORO) field campaign, led by principal investigator Andrew Vogelmann. During this long-term campaign, the AAF conducted routine flights at the ACRF Southern

464

Importance of Iron Mineralogy to Aerosol Solubility: Potential Effects of  

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

Importance of Iron Mineralogy to Importance of Iron Mineralogy to Aerosol Solubility: Potential Effects of Aerosol Source on Ocean Photosynthesis figure 1 Figure 1. Dust storm blowing glacial dusts from the Copper River Basin of southeast Alaska into the North Pacific Ocean, which depends on this and other external iron sources to support its biological communities. (Image: NASA MODIS satellite image, Nov. 1, 2006. http://earthobservatory.nasa.gov/IOTD/view.php?id=7094) Iron is one of the most important elements to life. Despite its paramount importance and relative abundance, dissolved iron concentrations are often very low, in part due to the formation of very stable iron minerals in most oxidizing environments. Since soluble iron is available to living organisms, iron deficiencies are widespread, and the factors that influence

465

Enhancement factors for resuspended aerosol radioactivity: Effects of topsoil disturbance  

SciTech Connect (OSTI)

The enhancement factor for airborne radionuclides resuspended by wind is defined as the ratio of the activity density (Bq g{sup {minus}1}) in the aerosol to the activity density in the underlying surface of contaminated soil. Enhancement factors are useful for assessment of worst-case exposure scenarios and transport conditions, and are one of the criteria for setting environmental standards for radioactivity in soil. This paper presents results of experimental studies where resuspension of {sup 239}Pu was measured when air concentrations were equilibrated to the soil surface. Enhancement factors were observed for several types of man-made disturbances (bulldozer-blading, soil raking, vacuum-cleaning) and natural disturbances (springtime thaw, soil-drying, wildfire). For some cases, enhancement factors are compared over range of geographical locations (Bikini Atoll, California, Nevada, and South Carolina). The particle-size distributions of aerosol activity are compared to particle-size distributions of the underlying soil.

Shinn, J.H.

1991-11-01T23:59:59.000Z

466

Study of formation and convective transport of aerosols using optical diagnostic technique  

E-Print Network [OSTI]

. To optimize VI performance, the characteristics of convective transport should be identified. This objective is achieved by visualization techniques. The applied visualization techniques are Mie-scattering and laser induced fluorescence (LIF). To investigate...

Kim, Tae-Kyun

2004-09-30T23:59:59.000Z

467

Variability in morphology, hygroscopicity, and optical properties of soot aerosols during atmospheric processing  

Science Journals Connector (OSTI)

...12), or engine combustion (16...mass, we draw fundamental conclusions of atmospheric...particles from diesel combustion by using combined...Properties of jet engine combustion particles...of carbon and diesel soot particles...vehicle with a diesel oxidation catalyst . J...Boubel RW ( 1994 ) Fundamentals of Air Pollution...

Renyi Zhang; Alexei F. Khalizov; Joakim Pagels; Dan Zhang; Huaxin Xue; Peter H. McMurry

2008-01-01T23:59:59.000Z

468

Satellite based retrieval of aerosol optical thickness: The effect of sun and satellite geometry  

E-Print Network [OSTI]

in the earth's energy balance by scattering and absorbing solar and terrestrial radiation [Chylek and Coakley Alamos, New Mexico, USA Michael Mishchenko Goddard Institute for Space Studies, NASA, New York, New York

469

Correlations between Optical, Chemical and Physical Properties of Biomass Burn Aerosols  

E-Print Network [OSTI]

of potassium in biomass combustion, Proceedings of thethan those from biomass combustion. In Figure 3, ? ap valuesspectral dependence for the biomass combustion particulates.

2008-01-01T23:59:59.000Z

470

Variations of aerosol optical properties during the extreme solar event in January 2005  

E-Print Network [OSTI]

to undergo nuclear reactions and produce a flux of neutrons detectable by ground-based neutron monitors. Some energy input of cosmic rays into the atmosphere is minor, they form the main source of ionization (cosmic ray induced ionization ­ CRII) of the low and middle atmosphere. Therefore, cosmic rays may, via CRII

Usoskin, Ilya G.

471

Laboratory Testing of Aerosol for Enclosure Air Sealing  

SciTech Connect (OSTI)

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.

Harrington, C.; Modera, M.

2012-05-01T23:59:59.000Z

472

Aerosol nucleation in coal-fired power-plant plumes  

Science Journals Connector (OSTI)

New-particle nucleation within coal-fired power-plant plumes can have large effects on particle number concentrations particularly near source regions with implications for human health and climate. In order to resolve the formation and growth of particles in these plumes we have integrated TwO-Moment Aerosol Sectional (TOMAS) microphysics in the System for Atmospheric Modelling (SAM) a large-eddy simulation/cloud-resolving model (LES/CRM). We have evaluated this model against aircraft observations for three case studies and the model reproduces well the major features of each case. Using this model we have shown that meteorology and background aerosol concentrations can have strong effects on new-particle formation and growth in coal-fired power-plant plumes even if emissions are held constant. We subsequently used the model to evaluate the effects of SO 2 and NOx pollution controls on newparticle formation in coal-fired power-plant plumes. We found that strong reductions in NOx emissions without concurrent reductions in SO 2 emissions may increase new-particle formation due to increases in OH formation within the plume. We predicted the change in new-particle formation due to changes in emissions between 1997 and 2010 for 330 coal-fired power plants in the US and we found a median decrease of 19% in new-particle formation. However the magnitude and sign of the aerosol changes depend greatly on the relative reductions in NOx and SO 2 emissions in each plant. More extensive plume measurements for a range of emissions of SO 2 and NOx and in varying background aerosol conditions are needed however to better quantify these effects.

2013-01-01T23:59:59.000Z

473

Research Highlights Sorted by Research Area  

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

Research Area Research Area Radiation Processes | Cloud Distributions/Characterizations | Surface Properties | General Circulation and Single Column Models/Parameterizations | Aerosol Properties | Atmospheric Thermodynamics and Vertical Structures | Clouds with Low Optical [Water] Depths (CLOWD) | Vertical Velocity | Broadband Heating Rate Profile (BBHRP) | Cloud-Aerosol-Precipitation Interactions | Cloud Processes | Aerosol Processes Radiation Processes Alexandrov, M. D. Optical Depth Measurements by Shadowband Radiometers and Their Uncertainties ARM Berg, L. Surface Summertime Radiative Forcing by Shallow Cumuli at the ARM SGP ARM Bergmann, D. The Influence of Regional Anthropogenic Emission Reductions on Aerosol Direct Radiative Forcing ASR Bhattacharya, A. Burning on the Prairies ARM

474

Vertically Loaded Anchor: Drag Coefficient, Fall Velocity, and Penetration Depth using Laboratory Measurements  

E-Print Network [OSTI]

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...

Cenac, William

2011-08-08T23:59:59.000Z

475

E-Print Network 3.0 - adjustable penetration depth Sample Search...  

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

2002; 54:365398 (DOI: 10.1002nme.427) Summary: data with the help of ash X-ray, e.g. penetration depth, rate of rod consumption, mass e ciency... conguration is the depth of...

476

Taking Oil and Gas Exploration to New Depths | GE Global Research  

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

Taking Oil and Gas Exploration to New Depths Taking Oil and Gas Exploration to New Depths Oliver Astley 2014.11.12 The challenges of offshore, deep sea drilling are, in a word,...

477

Optical NAND gate  

SciTech Connect (OSTI)

An optical NAND gate is formed from two pair of optical waveguide devices on a substrate, with each pair of the optical waveguide devices consisting of an electroabsorption modulator and a photodetector. One pair of the optical waveguide devices is electrically connected in parallel to operate as an optical AND gate; and the other pair of the optical waveguide devices is connected in series to operate as an optical NOT gate (i.e. an optical inverter). The optical NAND gate utilizes two digital optical inputs and a continuous light input to provide a NAND function output. The optical NAND 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.

Skogen, Erik J. (Albuquerque, NM); Raring, James (Goleta, CA); Tauke-Pedretti, Anna (Albuquerque, NM)

2011-08-09T23:59:59.000Z

478

Thermophoresis and its thermal parameters for aerosol collection  

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

Thermophoresis and its thermal parameters for aerosol collection Thermophoresis and its thermal parameters for aerosol collection Title Thermophoresis and its thermal parameters for aerosol collection Publication Type Journal Article Year of Publication 2007 Authors Huang, Zhuo, Michael G. Apte, and Lara A. Gundel Journal U.S. Department of Energy Journal of Undergraduate Research Volume 7 Pagination 37-42 Abstract The particle collection effi ciency of a prototype environmental tobacco smoke (ETS) sampler based on the use of thermophoresis is determined by optimizing the operational voltage that determines its thermal gradient. This sampler's heating element was made of three sets of thermophoretic (TP) wires 25µm in diameter suspended across a channel cut in a printed circuit board and mounted with collection surfaces on both sides. The separation between the heating element and the room temperature collection surface was determined in a numerical simulation based on the Brock-Talbot model. Other thermal parameters of this TP ETS sampler were predicted by the Brock-Talbot model for TP deposition. From the normalized results the optimal collection ratio was expressed in terms of operational voltage and fi lter mass. Prior to the Brock-Talbot model simulation for this sampler, 1.0V was used arbitrarily. The operational voltage was raised

479

Large historical changes of fossil-fuel black carbon aerosols  

SciTech Connect (OSTI)

Anthropogenic emissions of fine black carbon (BC) particles, the principal light-absorbing atmospheric aerosol, have varied during the past century in response to changes of fossil-fuel utilization, technology developments, and emission controls. We estimate historical trends of fossil-fuel BC emissions in six regions that represent about two-thirds of present day emissions and extrapolate these to global emissions from 1875 onward. Qualitative features in these trends show rapid increase in the latter part of the 1800s, the leveling off in the first half of the 1900s, and the re-acceleration in the past 50 years as China and India developed. We find that historical changes of fuel utilization have caused large temporal change in aerosol absorption, and thus substantial change of aerosol single scatter albedo in some regions, which suggests that BC may have contributed to global temperature changes in the past century. This implies that the BC history needs to be represented realistically in climate change assessments.

Novakov, T.; Ramanathan, V.; Hansen, J.E.; Kirchstetter, T.W.; Sato, M.; Sinton, J.E.; Sathaye, J.A.

2002-09-26T23:59:59.000Z

480

Aerosol-Derived Bimetallic Alloy Powders: Bridging the Gap  

SciTech Connect (OSTI)

We present aerosol-derived alloy powders as a uniquely useful platform for studying the contribution of the metal phase to multifunctional supported catalysts. Multimetallic heterogeneous catalysts made by traditional methods are usually nonhomogenous while UHV-based methods, such as mass selected clusters or metal vapor deposited on single crystals, lead to considerably more homogeneous, well-defined samples. However, these well-defined samples have low surface areas and do not lend themselves to catalytic activity tests in flow reactors under industrially relevant conditions. Bimetallic alloy powders derived by aerosol synthesis are homogeneous and single phase and can have surface areas ranging 1-10 m2/g, making them suitable for use in conventional flow reactors. The utility of aerosol-derived alloy powders as model catalysts is illustrated through the synthesis of single phase PdZn which was used to derive the specific reactivity of the L10 tetragonal alloy phase for methanol steam reforming. Turnover frequencies on unsupported PdZn were determined from the experimentally determined metal surface area to be 0.21 molecules of methanol reacted per surface Pd at 250 C and 0.06 molecules of CO oxidized to CO2 per surface Pd at 185 C. The experimentally measured activation energies for MSR and CO-oxidation on PdZn are 48 and 87 kJ/mol, respectively.

Halevi, Barr; Peterson, Eric; DelaRiva, Andrew; Jeroro, E.; Lebarbier, Vanessa MC; Wang, Yong; Vohs, John M.; Kiefer, Boris; Kunkes, Edward L.; Havecker , Michael; Behrens, Malte; Schlogl, Robert; Datye, Abhaya K.

2010-09-03T23:59:59.000Z

Note: This page contains sample records for the topic "aerosol optical depth" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


481

Source terms for plutonium aerosolization from nuclear weapon accidents  

SciTech Connect (OSTI)

The source term literature was reviewed to estimate aerosolized and respirable release fractions for accidents involving plutonium in high-explosive (HE) detonation and in fuel fires. For HE detonation, all estimates are based on the total amount of Pu. For fuel fires, all estimates are based on the amount of Pu oxidized. I based my estimates for HE detonation primarily upon the results from the Roller Coaster experiment. For hydrocarbon fuel fire oxidation of plutonium, I based lower bound values on laboratory experiments which represent accident scenarios with very little turbulence and updraft of a fire. Expected values for aerosolization were obtained from the Vixen A field tests, which represent a realistic case for modest turbulence and updraft, and for respirable fractions from some laboratory experiments involving large samples of Pu. Upper bound estimates for credible accidents are based on experiments involving combustion of molten plutonium droplets. In May of 1991 the DOE Pilot Safety Study Program established a group of experts to estimate the fractions of plutonium which would be aerosolized and respirable for certain nuclear weapon accident scenarios.

Stephens, D.R.

1995-07-01T23:59:59.000Z

482

Control Systems Cyber Security:Defense in Depth Strategies  

SciTech Connect (OSTI)

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.

David Kuipers; Mark Fabro

2006-05-01T23:59:59.000Z

483

Quantifying the Aerosol Indirect Effect Using Ground-Based Remote Sensors and Models  

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

Quantifying the Aerosol Indirect Effect Quantifying the Aerosol Indirect Effect Using Ground-Based Remote Sensors and Models G. Feingold National Oceanic and Atmospheric Administration Environmental Technology Laboratory Boulder, Colorado D. E. Lane Rutgers University Camden, New Jersey Q.-L. Min Atmospheric Sciences Research Center State University of New York Albany, New York Introduction The effect of aerosols on cloud microphysical and radiative properties (the "indirect effect") has the greatest uncertainty of all known climate-forcing mechanisms. Increases in aerosol concentrations result in higher concentrations of cloud condensation nuclei (CCN), increased cloud droplet concentrations, and smaller droplet sizes (Twomey 1974). A possible secondary effect is the suppression of rainfall.

484

E-Print Network 3.0 - aerosol mass spectrometry Sample Search...  

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

used in health effects studies by aerosol mass spectrometry Wingen, L... and heats of sublimation using atmospheric solids analysis probe mass spectrometry (ASAP-MS) Bruns E......

485

Ultraclean Two-Stage Aerosol Reactor for Production of Oxide-Passivated Silicon Nanoparticles for Novel  

E-Print Network [OSTI]

as an aerosol by pyrolysis of silane3 or disilane4 or by thermal evaporation of Si.5 In studies of Si

Atwater, Harry

486