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1

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

NLE Websites -- All DOE Office Websites (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

2

ARM - Campaign Instrument - aerosmassspec  

NLE Websites -- All DOE Office Websites (Extended Search)

govInstrumentsaerosmassspec govInstrumentsaerosmassspec Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign Instrument : Aerosol Mass Spectrometer (AEROSMASSSPEC) Instrument Categories Aerosols, Atmospheric Carbon, Airborne Observations Campaigns 2006 MAX-Mex-Megacity Aerosol eXperiment - Mexico City [ Download Data ] Off Site Campaign : various, including non-ARM sites, 2006.03.03 - 2006.03.28 2007 Cumulus Humilis Aerosol Process Study (CHAPS) [ Download Data ] Off Site Campaign : various, including non-ARM sites, 2007.06.04 - 2007.06.25 2008 VAMOS Ocean-Cloud-Atmos-Land Study (VOCALS) [ Download Data ] Off Site Campaign : various, including non-ARM sites, 2008.10.14 - 2008.11.13 Carbonaceous Aerosol and Radiative Effects Study (CARES) [ Download Data ]

3

ARM Cloud Aerosol Precipitation Experiment  

NLE Websites -- All DOE Office Websites (Extended Search)

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

4

Experiments related to the resuspension of aerosols during hydrogen burns  

SciTech Connect

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

5

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

6

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

SciTech Connect

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

7

ARM - Field Campaign - Ganges Valley Aerosol Experiment (GVAX)  

NLE Websites -- All DOE Office Websites (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

8

Ganges Valley Aerosol Experiment: Science and Operations Plan  

SciTech Connect

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

9

MELCOR 1.8.2 assessment: Aerosol experiments ABCOVE AB5, AB6, AB7, and LACE LA2  

SciTech Connect

The MELCOR computer code has been used to model four of the large-scale aerosol behavior experiments conducted in the Containment System Test Facility (CSTF) vessel. Tests AB5, AB6 and AB7 of the ABCOVE program simulate the dry aerosol conditions during a hypothetical severe accident in an LMFBR. Test LA2 of the LACE program simulates aerosol behavior in a condensing steam environment during a postulated severe accident in an LWR with failure to isolate the containment. The comparison of code results to experimental data show that MELCOR is able to correctly predict most of the thermal-hydraulic results in the four tests. MELCOR predicts reasonably well the dry aerosol behavior of the ABCOVE tests, but significant disagreements are found in the aerosol behavior modelling for the LA2 experiment. These results tend to support some of the concerns about the MELCOR modelling of steam condensation onto aerosols expressed in previous works. During these analyses, a limitation in the MELCOR input was detected for the specification of the aerosol parameters for more than one component. A Latin Hypercube Sampling (LHS) sensitivity study of the aerosol dynamic constants is presented for test AB6. The study shows the importance of the aerosol shape factors in the aerosol deposition behavior, and reveals that MELCOR input/output processing is highly labor intensive for uncertainty and sensitivity analyses based on LHS.

Souto, F.J.; Haskin, F.E. [Univ. of New Mexico, Albuquerque, NM (United States). Dept. of Chemical and Nuclear Engineering; Kmetyk, L.N. [Sandia National Labs., Albuquerque, NM (United States)

1994-10-01T23:59:59.000Z

10

Atmospheric Radiation Measurment (ARM) Data from the Ganges Valley, India for the Ganges Valley Aerosol Experiment (GVAX)  

DOE Data Explorer (OSTI)

In 2011 and 2012, the Ganges Valley Aerosol Experiment (GVAX) began in the Ganges Valley region of India. The objective was to obtain measurements of clouds, precipitation, and complex aerosols to study their impact on cloud formation and monsoon activity in the region. During the Indian Ocean Experiment (INDOEX) field studies, aerosols from the Ganges Valley region were shown to affect cloud formation and monsoon activity over the Indian Ocean. The complex field study used the ARM Mobile Facility (AMF) to measure radiative, cloud, convection, and aerosol characteristics over the mainland. The resulting data set captured pre-monsoon to post-monsoon conditions to establish a comprehensive baseline for advancements in the study of the effects of atmospheric conditions of the Ganges Valley.

11

DOE/SC-ARM-10-019 Ganges Valley Aerosol Experiment: Science and  

NLE Websites -- All DOE Office Websites (Extended Search)

9 9 Ganges Valley Aerosol Experiment: Science and Operations Plan VR Kotamarthi, Argonne National Laboratory June 2010 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or

12

The Joint AerosolMonsoon Experiment: A New Challenge for Monsoon Climate Research  

Science Journals Connector (OSTI)

Aerosol- and moonsoon-related droughts and floods are two of the most serious environmental hazards confronting more than 60% of the population of the world living in the Asian monsoon countries. In recent years, thanks to improved satellite and ...

K-M. Lau; S. C. Tsay; C. Hsu; M. Chin; V. Ramanathan; G-X. Wu; Z. Li; R. Sikka; B. Holben; D. Lu; H. Chen; G. Tartari; P. Koudelova; Y. Ma; J. Huang; K. Taniguchi; R. Zhang

2008-03-01T23:59:59.000Z

13

The technical basis for air pathway assessment of resuspended radioactive aerosols: LLNL experiences at seven sites around the world  

SciTech Connect

There is a large uncertainty in quantifying the inhalation pathway and the aerosol emission rate in human health assessments of radioactive-contamination sites. The need for site-specific assessments led to formation of our team of specialists at LLNL, who have participated in numerous field campaigns around the world. Our goal was to obtain all the information necessary for determining potential human exposures and to estimate source terms for turbulent transport of the emissions during both normal and disturbed soil conditions. That is, measurements were made of the key variables to quantify the suspended aerosols at the actual contamination sites, but different scenarios for habitation, site management, and site cleanup were included. The most notable locations of these site-investigations were the Marshall Islands (Bikini, Enewetak, and Rongelap), Nevada Test Site (GMX, Little Feller, Palanquin, and Plutonium Valley), Tonopah (Nevada--site of Roller Coaster), Savannah River Lab (South Carolina--H-Area site), Johnston Island (cleanup of rocket-impact site), Chernobyl (Ukraine--grass field end sandy beach sites near Nuclear Power Plant Unit 4), and Palomares (Spain--site of aircraft accident). This discussion will review the variables quantified, methods developed, general results, uncertainty of estimations, and recommendations for future research that are a result of our experience in these field studies.

Shinn, J.H.

1993-09-01T23:59:59.000Z

14

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

15

aerosols | EMSL  

NLE Websites -- All DOE Office Websites (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...

16

Aerosol Laboratory - Nuclear Engineering Division (Argonne)  

NLE Websites -- All DOE Office Websites (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

17

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

18

Preface to special section on East Asian Studies of Tropospheric Aerosols: An International Regional Experiment (EAST-AIRE)  

E-Print Network (OSTI)

that reduced daily mean surface solar radiation by $30­40 W m?2 , but barely changed solar reflection second highest in the world next to Africa (Table 1). Coexistence of dust, industrial pollutants Asia. [3] Increasing evidence suggests that the influence of aerosols on the energy and water cycles

Li, Zhanqing

19

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

20

Measurements of NO2 and Analysis of Submicron Aerosol Composition in the ARM-Related Experiment at Zvenigorod in March-April 2002 and During Forest and Peatbog Fires in July-September 2002  

NLE Websites -- All DOE Office Websites (Extended Search)

Measurements of NO Measurements of NO 2 and Analysis of Submicron Aerosol Composition in the ARM-Related Experiment at Zvenigorod in March-April 2002 and During Forest and Peatbog Fires in July-September 2002 L. M. Shukurova, A. S. Elokhov, K. A. Shukurov, A. N. Gruzdev, and G. S. Golitsyn A.M. Obukhov Institute of Atmospheric Physics Russian Academy of Sciences Moscow, Russia Introduction One insufficiently explored problem is the effect of pollution of the lower troposphere by nitrogen oxides on the chemical composition and microphysical properties of atmospheric aerosol. Earlier experimental studies showed that submicron aerosol collected during anthropogenic pollution episodes in winter could contain the nitric acid component (Shukurova et al. 2001). In this study, we present

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

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

22

ARM - Measurement - Aerosol absorption  

NLE Websites -- All DOE Office Websites (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

23

ARM - Measurement - Aerosol concentration  

NLE Websites -- All DOE Office Websites (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

24

Carbonaceous Aerosols and Radiative...  

NLE Websites -- All DOE Office Websites (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...

25

Integrating biomass, sulphate and sea-salt aerosol responses into a microphysical chemical parcel model: implications for climate studies  

Science Journals Connector (OSTI)

...John Schellnhuber Integrating biomass, sulphate and sea-salt aerosol...biomass burning. In Global biomass burning: atmospheric, climatic...particles from African savanna combustion experiments. Atmos. Res...99)00329-5 . Integrating biomass, sulphate and sea-salt aerosol...

2007-01-01T23:59:59.000Z

26

Direct Aerosol Forcing Uncertainty  

DOE Data Explorer (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

27

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

28

BNL | Aerosol Lifecycle IOP  

NLE Websites -- All DOE Office Websites (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?

29

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

30

ARM - Measurement - Aerosol particle size  

NLE Websites -- All DOE Office Websites (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

31

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

32

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

NLE Websites -- All DOE Office Websites (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,

33

Experiences  

NLE Websites -- All DOE Office Websites (Extended Search)

Experiences Experiences with 100Gbps Network Applications Mehmet Balman, Eric Pouyoul, Yushu Yao, E. Wes Bethel Burlen Loring, Prabhat, John Shalf, Alex Sim, and Brian L. Tierney Lawrence Berkeley National Laboratory One Cyclotron Road Berkeley, CA, 94720, USA {mbalman,epouyoul,yyao,ewbethel,bloring,prabhat,jshalf,asim,btierney}@lbl.gov ABSTRACT 100Gbps networking has finally arrived, and many research and educational institutions have begun to deploy 100Gbps routers and services. ESnet and Internet2 worked together to make 100Gbps networks available to researchers at the Supercomputing 2011 con- ference in Seattle Washington. In this paper, we describe two of the first applications to take advantage of this network. We demon- strate a visualization application that enables remotely located sci- entists to gain insights from large datasets. We also demonstrate climate

34

Characterizing the formation of secondary organic aerosols  

SciTech Connect

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

35

Geometrical Optics of Dense Aerosols  

SciTech Connect

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

36

BNL | Aerosol, Cloud, Precipitation Interactions  

NLE Websites -- All DOE Office Websites (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.

37

Jankovic Aerosol Characterization.ppt  

NLE Websites -- All DOE Office Websites (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)

38

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

39

Representing Cloud Processing of Aerosol in Numerical Models  

SciTech Connect

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

40

Aerosols in a Changing Atmosphere: From Detailed Aerosol Microphysics to  

NLE Websites -- All DOE Office Websites (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

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

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.

42

ARM - Mobile Aerosol Observing System  

NLE Websites -- All DOE Office Websites (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

43

Aerosol Observing System (AOS) Handbook  

SciTech Connect

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

44

EMSL: Science: Atmospheric Aerosol Systems  

NLE Websites -- All DOE Office Websites (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.

45

Two-Column Aerosol Project  

NLE Websites -- All DOE Office Websites (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...

46

Molecular Characterization of Biomass Burning Aerosols Using...  

NLE Websites -- All DOE Office Websites (Extended Search)

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

47

SAGE II long-term measurements of stratospheric and upper tropospheric aerosols  

SciTech Connect

The Stratospheric Aerosol and Gas Experiment (SAGE) II solar occultation instrument has been making measurements on stratospheric aerosols and gases continually since October 1984. Observations from the SAGE II instrument provide a valuable long-term data set for study of the aerosol in the stratosphere and aerosol and cloud in the upper troposphere. The period of observation covers the decay phase of material injected by the El Chichon volcanic eruption in 1982, the years 1988--1990 when stratospheric aerosol levels approached background levels, and the period after the eruption of Mount Pinatubo in 1991. The Mount Pinatubo eruption caused the largest perturbation in stratospheric aerosol loading in this century, with effects on stratospheric dynamics and chemistry. The SAGE II data sequence shows the global dispersion of aerosols following the Mount Pinatubo eruption, as well as the changes occurring in stratospheric aerosol mass and surface area. The downward transfer of stratospheric aerosols into the upper troposphere following the earlier eruption of El Chichon is clearly visible. Estimates have been made of the amount of volcanic material lying in the upper troposphere and the way in which this varies with latitude and season.

Wang, P.H.; Kent, G.S. [Science and Technology Corp., Hampton, VA (United States); McCormick, M.P.; Thomason, L.W. [NASA Langley Research Center, Hampton, VA (United States). Atmospheric Sciences Div.

1995-12-31T23:59:59.000Z

48

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

49

Heterogeneous Surface-Based Freezing of Atmospheric Aerosols Containing Ash, Soot, and Soil  

E-Print Network (OSTI)

nucleation will occur through one of several mechanisms including the contact and immersion freezing mechanisms. Through a series of contact freezing experiments, we have characterized the ability of aerosols composed of volcanic ash, soot, and peat soil...

Fornea, Adam P.

2010-07-14T23:59:59.000Z

50

DOE research on atmospheric aerosols  

SciTech Connect

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

51

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

SciTech Connect

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

52

Evolution of Asian aerosols during transpacific transport in INTEX-B  

SciTech Connect

Measurements of aerosol composition were made with an Aerodyne High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) on board the NSF/NCAR C-130 aircraft as part of the Intercontinental Chemical Transport Experiment Phase B 5 (INTEX-B) field campaign over the Eastern Pacific Ocean. The HR-ToF-AMS measurements of non-refractory submicron aerosol mass are shown to compare well with other aerosol instrumentation in the INTEX-B field study. Two case studies are described for pollution layers transported across the Pacific from the Asian continent, intercepted 34 days and 710 days downwind of Asia, respectively. Aerosol chemistry is shown to 10 be a robust tracer for air masses originating in Asia, specifically the presence of sulfate dominated aerosol is a distinguishing feature of Asian pollution layers that have been transported to the Eastern Pacific. We examine the time scales of processing for sulfate and organic aerosol in the atmosphere and show that our observations confirm a conceptual model for transpacific transport from Asia proposed by Brock et al. (2004). 15 Our observations of both sulfate and organic aerosol in aged Asian pollution layers are consistent with fast formation near the Asian continent, followed by washout during lofting and subsequent transformation during transport across the Pacific. Our observations are the first atmospheric measurements to indicate that although secondary organic aerosol (SOA) formation from pollution happens on the timescale of one day, 20 the oxidation of organic aerosol continues at longer timescales in the atmosphere. Comparisons with chemical transport models of data from the entire campaign reveal an under-prediction of SOA mass in the MOZART model, but much smaller discrepancies with the GEOS-Chem model than found in previous studies over the Western Pacific. No evidence is found to support a previous hypothesis for significant secondary 25 organic aerosol formation in the free troposphere.

Dunlea, E. J.; DeCarlo, Peter; Aiken, Allison; Kimmel, Joel; Peltier, R. E.; Weber, R. J.; Tomlinson, Jason M.; Collins, Donald R.; Shinozuka, Yohei; McNaughton, C. S.; Howell, S. G.; Clarke, A. D.; Emmons, L.; Apel, Eric; Pfister, G. G.; van Donkelaar, A.; Martin, R. V.; Millet, D. B.; Heald, C. L.; Jimenez, J. L.

2009-10-01T23:59:59.000Z

53

Distinguishing Aerosol Impacts on Climate Over the Past Century  

SciTech Connect

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

54

ARM - Surface Aerosol Observing System  

NLE Websites -- All DOE Office Websites (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

55

On surface temperature, greenhouse gases, and aerosols: models and observations  

SciTech Connect

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

56

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

57

ARM - Evaluation Product - Organic Aerosol Component VAP  

NLE Websites -- All DOE Office Websites (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

58

ARM - Field Campaign - Fall 1997 Aerosol IOP  

NLE Websites -- All DOE Office Websites (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

59

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

60

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

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

62

Source terms for plutonium aerosolization from nuclear weapon accidents  

SciTech Connect

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

63

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

64

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

65

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

66

ARM - Measurement - Aerosol optical depth  

NLE Websites -- All DOE Office Websites (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

67

ARM - Measurement - Aerosol optical properties  

NLE Websites -- All DOE Office Websites (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

68

ARM - Measurement - Aerosol backscattered radiation  

NLE Websites -- All DOE Office Websites (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

69

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

70

Review of models applicable to accident aerosols  

SciTech Connect

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

71

Particles and People: Aerosol Movement Into and Around the Human Body  

NLE Websites -- All DOE Office Websites (Extended Search)

Particles and People: Aerosol Movement Into and Around the Human Body Particles and People: Aerosol Movement Into and Around the Human Body Speaker(s): Miriam Byrne Date: April 14, 2006 - 12:00pm Location: Bldg. 90 Miriam Byrne is a participating guest in the Airflow and Pollutant Transport Group at LBL. She is an academic member of staff in the Physics Department at the National University of Galway, Ireland. Her research interests, primarily funded by European Commission radiation protection programs, focus on the mechanisms of aerosol transport to and from human body surfaces. Over the last ten years, she has been involved in tracer aerosol experiments to determine rates of particle deposition and resuspension from skin, hair and clothing, as well as studying particle transport into skin pores and hair follicles, and contact transfer from

72

Investigation of Aerosol Indirect Effects using a Cumulus Microphysics Parameterization in a Regional Climate Model  

SciTech Connect

A new Zhang and McFarlane (ZM) cumulus scheme includes a two-moment cloud microphysics parameterization for convective clouds. This allows aerosol effects to be investigated more comprehensively by linking aerosols with microphysical processes in both stratiform clouds that are explicitly resolved and convective clouds that are parameterized in climate models. This new scheme is implemented in the Weather Research and Forecasting (WRF) model, which is coupled with the physics and aerosol packages from the Community Atmospheric Model version 5 (CAM5). A test case of July 2008 during the East Asian summer monsoon is selected to evaluate the performance of the new ZM scheme and to investigate aerosol effects on monsoon precipitation. The precipitation and radiative fluxes simulated by the new ZM scheme show a better agreement with observations compared to simulations with the original ZM scheme that does not include convective cloud microphysics and aerosol convective cloud interactions. Detailed analysis suggests that an increase in detrained cloud water and ice mass by the new ZM scheme is responsible for this improvement. To investigate precipitation response to increased anthropogenic aerosols, a sensitivity experiment is performed that mimics a clean environment by reducing the primary aerosols and anthropogenic emissions to 30% of that used in the control simulation of a polluted environment. The simulated surface precipitation is reduced by 9.8% from clean to polluted environment and the reduction is less significant when microphysics processes are excluded from the cumulus clouds. Ensemble experiments with ten members under each condition (i.e., clean and polluted) indicate similar response of the monsoon precipitation to increasing aerosols.

Lim, Kyo-Sun; Fan, Jiwen; Leung, Lai-Yung R.; Ma, Po-Lun; Singh, Balwinder; Zhao, Chun; Zhang, Yang; Zhang, Guang; Song, Xiaoliang

2014-01-29T23:59:59.000Z

73

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

74

ARM - PI Product - Direct Aerosol Forcing Uncertainty  

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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

75

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

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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

76

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

77

Separating Cloud Forming Nuclei from Interstitial Aerosol  

SciTech Connect

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

78

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

79

Ash aerosol formation from oxy-coal combustion and its relation to ash deposit chemistry  

Science Journals Connector (OSTI)

Abstract Ash aerosol and ash deposit formation during oxy-coal combustion were explored through experiments in a self-sustained 100kW rated down-fired oxy-fuel combustor. Inlet oxidant conditions consisted of 50% inlet oxygen with CO2 (hereafter denoted as OXY50 conditions). A Berner low pressure impactor (BLPI), a scanning mobility particle sizer (SMPS), and an aerodynamic particle sizer (APS) were used to obtain size segregated ash aerosol samples and to determine the particle size distributions (PSD). A novel surface temperature controlled ash deposition probe system that allowed inside and outside deposits to be separated was used to collect the ash deposits. The ash aerosol \\{PSDs\\} given by the BLPI and those produced by SMPS/APS were consistent with each other. Data suggested that oxy-coal combustion under these conditions did not change the formation mechanisms controlling the bulk ash aerosol composition, but it did increase the formation of ultra-fine particles initially formed through metal vaporization, due to increased vaporization of silicon at the higher combustion temperature. The smaller particles contained within the deposits had higher Si and lower Na and S concentrations under OXY50 conditions than for air combustion. Moreover, the ash aerosol composition for particle sizes less than 2.4?m was related to the composition of the inside deposits. A higher Na in the ash aerosol resulted in higher Na in inside deposits with comparable absolute Na concentrations in both those aerosol particles and those inside deposits particles. The contribution of S and Si to the inside deposits showed that S in the vaporization modes together with Si in the ultrafine vaporization mode, contributed significantly to the composition of the inside deposits. These results provided direct evidence that prediction of the chemistry of the initial deposit layer (but not of the bulk deposits) required knowledge of the size segregated chemistry of the ash aerosol.

Zhonghua Zhan; Andrew Fry; Yanwei Zhang; Jost O.L. Wendt

2014-01-01T23:59:59.000Z

80

Comparative Analysis of Urban Atmospheric Aerosol by Particle...  

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

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

The Two-Column Aerosol Project Definitions TCAP Educational  

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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...

82

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

83

The Indirect and Semi-Direct Aerosol Campaign  

SciTech Connect

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

84

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

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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...

85

Molecular Chemistry of Organic Aerosols Through the Application...  

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

86

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

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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...

87

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

SciTech Connect

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

88

Laboratory and field testing of an aerosol-based duct-sealing technology  

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Laboratory and field testing of an aerosol-based duct-sealing technology Laboratory and field testing of an aerosol-based duct-sealing technology for large commercial buildings. Title Laboratory and field testing of an aerosol-based duct-sealing technology for large commercial buildings. Publication Type Journal Article LBNL Report Number LBNL-44220 Year of Publication 2002 Authors Carrié, François Rémi, Ronnen M. Levinson, Tengfang T. Xu, Darryl J. Dickerhoff, William J. Fisk, Jennifer A. McWilliams, Mark P. Modera, and Duo Wang Journal ASHRAE Transactions Start Page Chapter Date Published January 2002 Abstract Laboratory and field experiments were performed to evaluate the feasibility of sealing leaks in commercial duct systems with an aerosol sealant. The method involves blowing an aerosol through the duct system to seal the leaks from the inside, the principle being that the aerosol particles deposit in the cracks as they try to escape under pressure. It was shown that the seals created with the current sealant material can withstand pressures far in excess of what is found in commercial-building duct systems. We also performed two field experiments in two large-commercial buildings. The ASHRAE leakage classes of the systems were reduced from 653 down to 103, and from 40 down to 3. Methods and devices specifically devised for this application proved to be very efficient at (a) increasing the sealing rate and (b) attaining state-of-the-art duct leakage classes. Additional research is needed to improve the aerosol injection and delivery processes.

89

Aerosol plume transport and transformation in high spectral resolution lidar measurements and WRF-Flexpart simulations during the MILAGRO Field Campaign  

E-Print Network (OSTI)

The Mexico City Metropolitan Area (MCMA) experiences high loadings of atmospheric aerosols from anthropogenic sources, biomass burning and wind-blown dust. This paper uses a combination of measurements and numerical ...

de Foy, B.

90

BNL | Mobile Aerosol Observing System (MAOS)  

NLE Websites -- All DOE Office Websites (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

91

The Opposed Migration Aerosol Classifier (OMAC)  

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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

92

Improving Bulk Microphysics Parameterizations in Simulations of Aerosol Effects  

SciTech Connect

To improve the microphysical parameterizations for simulations of the aerosol indirect effect (AIE) in regional and global climate models, a double-moment bulk microphysical scheme presently implemented in the Weather Research and Forecasting (WRF) model is modified and the results are compared against atmospheric observations and simulations produced by a spectral bin microphysical scheme (SBM). Rather than using prescribed aerosols as in the original bulk scheme (Bulk-OR), a prognostic doublemoment aerosol representation is introduced to predict both the aerosol number concentration and mass mixing ratio (Bulk-2M). The impacts of the parameterizations of diffusional growth and autoconversion and the selection of the embryonic raindrop radius on the performance of the bulk microphysical scheme are also evaluated. Sensitivity modeling experiments are performed for two distinct cloud regimes, maritime warm stratocumulus clouds (SC) over southeast Pacific Ocean from the VOCALS project and continental deep convective clouds (DCC) in the southeast of China from the Department of Energy/ARM Mobile Facility (DOE/AMF) - China field campaign. The results from Bulk-2M exhibit a much better agreement in the cloud number concentration and effective droplet radius in both the SC and DCC cases with those from SBM and field measurements than those from Bulk-OR. In the SC case particularly, Bulk-2M reproduces the observed drizzle precipitation, which is largely inhibited in Bulk-OR. Bulk-2M predicts enhanced precipitation and invigorated convection with increased aerosol loading in the DCC case, consistent with the SBM simulation, while Bulk-OR predicts the opposite behaviors. Sensitivity experiments using four different types of autoconversion schemes reveal that the autoconversion parameterization is crucial in determining the raindrop number, mass concentration, and drizzle formation for warm 2 stratocumulus clouds. An embryonic raindrop size of 40 ?m is determined as a more realistic setting in the autoconversion parameterization. The saturation adjustment employed in calculating condensation/evaporation in the bulk scheme is identified as the main factor responsible for the large discrepancies in predicting cloud water in the SC case, suggesting that an explicit calculation of diffusion growth with predicted supersaturation is necessary for further improvements of the bulk microphysics scheme. Lastly, a larger rain evaporation rate below cloud is found in the bulk scheme in comparison to the SBM simulation, which could contribute to a lower surface precipitation in the bulk scheme.

Wang, Yuan; Fan, Jiwen; Zhang, Renyi; Leung, Lai-Yung R.; Franklin, Charmaine N.

2013-06-05T23:59:59.000Z

93

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

94

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

95

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

96

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

NLE Websites -- All DOE Office Websites (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...

97

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

NLE Websites -- All DOE Office Websites (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...

98

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

NLE Websites -- All DOE Office Websites (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...

99

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

SciTech Connect

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

100

CARES: Carbonaceous Aerosol and Radiative Effects Study Science Plan  

SciTech Connect

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

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

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

NLE Websites -- All DOE Office Websites (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

102

Aerosol Radiative Forcing Under Cloudless Conditions.in Winter ZCAREX-2001  

NLE Websites -- All DOE Office Websites (Extended Search)

Forcing Under Cloudless Conditions Forcing Under Cloudless Conditions in Winter ZCAREX-2001 G. S. Golitsyn, I. A. Gorchakova, and I. I. Mokhov Institute of Atmospheric Physic Moscow, Russia Introduction Aerosol radiative forcing (ARF) is estimated for winter clear-sky conditions from measurements during ZCAREX-2001-Cloud-Aerosol-Radiation Experiment in February-March, 2001 at the Zvenigorod Scientific Station (ZSS) of the A.M. Obukhov Institute of Atmospheric Physics RAS. ARF in the shortwave range is determined by the difference between the net fluxes of the solar radiation, calculated with and without the aerosol component of the atmosphere. The estimates of ARF are made for conditions with high surface albedo. Data Used The following data of atmospheric characteristics observed during winter are used for the

103

Capstone Depleted Uranium Aerosols: Generation and Characterization  

SciTech Connect

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

104

Emission Controls Versus Meteorological Conditions in Determining Aerosol Concentrations in Beijing during the 2008 Olympic Games  

SciTech Connect

A series of emission control measures were undertaken in Beijing and the adjacent provinces in China during the 2008 Beijing Olympic Games on August 8th-24th, 2008. This provides a unique opportunity for investigating the effectiveness of emission controls on air pollution in Beijing. We conducted a series of numerical experiments over East Asia for the period of July to September 2008 using a coupled meteorology-chemistry model (WRF-Chem). Model can generally reproduce the observed variation of aerosol concentrations. Consistent with observations, modeled concentrations of aerosol species (sulfate, nitrate, ammonium, black carbon, organic carbon, total particulate matter) in Beijing were decreased by 30-50% during the Olympic period compared to the other periods in July and August in 2008 and the same period in 2007. Model results indicate that emission controls were effective in reducing the aerosol concentrations by comparing simulations with and without emission controls. However, our analysis suggests that meteorological conditions (e.g., wind direction and precipitation) are at least as important as emission controls in producing the low aerosol concentrations appearing during the Olympic period. Transport from the regions surrounding Beijing determines the temporal variation of aerosol concentrations in Beijing. Based on the budget analysis, we suggest that emission control strategy should focus on the regional scale instead of the local scale to improve the air quality over Beijing.

Gao, Yi; Liu, Xiaohong; Zhao, Chun; Zhang, Meigen

2011-12-12T23:59:59.000Z

105

Southern hemisphere tropospheric aerosol microphysics  

SciTech Connect

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

106

Composition and Reactions of Atmospheric Aerosol Particles  

NLE Websites -- All DOE Office Websites (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.

107

ARM - Measurement - Aerosol particle size distribution  

NLE Websites -- All DOE Office Websites (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

108

Composition and Reactions of Atmospheric Aerosol Particles  

NLE Websites -- All DOE Office Websites (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.

109

BNL | Two-Column Aerosol Program (TCAP)  

NLE Websites -- All DOE Office Websites (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

110

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

111

Aerosol Best Estimate Value-Added Product  

SciTech Connect

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

112

Composition and Reactions of Atmospheric Aerosol Particles  

NLE Websites -- All DOE Office Websites (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.

113

ARM - Field Campaign - Aerosol Life Cycle IOP at BNL  

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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.

114

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

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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

115

DETERMINATION OF RADIAL MOMENTS OF AN AEROSOL  

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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

116

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

117

Electrically Driven Technologies for Radioactive Aerosol Abatement  

SciTech Connect

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

118

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

119

ARM - Field Campaign - ARM Cloud Aerosol Precipitation Experiment...  

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receives precipitation predominantly during the cold season when storms approach from the Pacific Ocean. The snowpack that accumulates during winter storms provides about 70-90% of...

120

Atmospheric Aerosol Chemistry Analyzer: Demonstration of feasibility  

SciTech Connect

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

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

Chemical Composition and Sources of Coastal Marine Aerosol Particles during the 2008 VOCALS-REx Campaign  

SciTech Connect

The chemical composition of aerosol particles (Dp 1.5 ?m) was measured over the southeast Pacific Ocean during the VAMOS (Variability of the American Monsoon Systems) Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-Rex) between 16 October and 15 November 2008 using the US Department of Energy (DOE) G-1 aircraft. The objective of these flights was to gain an understanding of the sources and evolution of these aerosols, and of how they interact with the marine stratus cloud layer that prevails in this region of the globe. Our measurements showed that the marine boundary layer (MBL) aerosol mass was dominated by non-sea-salt SO2?4, followed by Na+, Cl?, Org (total organics), NH+4 , and NO?3 , in decreasing order of importance; CH3SO?3 (MSA), Ca2+, and K+ rarely exceeded their limits of detection. Aerosols were strongly acidic with a NH+4 to SO2?4 equivalents ratio typically < 0.3. Sea-salt aerosol (SSA) particles, represented by NaCl, exhibited Cl? deficits caused by both HNO3 and H2SO4, but for the most part were externally mixed with particles, mainly SO2?4. SSA contributed only a small fraction of the total accumulation mode particle number concentration. It was inferred that all aerosol species (except SSA) were of predominantly continental origin because of their strong land-to-sea concentration gradient. Comparison of relative changes in median values suggests that (1) an oceanic source of NH3 is present between 72 W and 76 W, (2) additional organic aerosols from biomass burns or biogenic precursors were emitted from coastal regions south of 31 S, with possible cloud processing, and (3) free tropospheric (FT) contributions to MBL gas and aerosol concentrations were negligible. The very low levels of CH3SO?3 observed as well as the correlation between SO2?4 and NO?3 (which is thought primarily anthropogenic) suggest a limited contribution of DMS to SO2?4 aerosol production during VOCALS.

Lee, Y.- N.; Springston, S.; Jayne, John T.; Wang, Jian; Hubbe, John M.; Senum, Gunnar I.; Kleinman, Lawrence I.; Daum, Peter H.

2014-05-23T23:59:59.000Z

122

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

123

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

124

Linearity of Climate Response to Increases in Black Carbon Aerosols  

SciTech Connect

The impact of absorbing aerosols on global climate are not completely understood. Here, we present results of idealized experiments conducted with the Community Atmosphere Model (CAM4) coupled to a slab ocean model (CAM4-SOM) to simulate the climate response to increases in tropospheric black carbon aerosols (BC) by direct and semi-direct effects. CAM4-SOM was forced with 0, 1x, 2x, 5x and 10x an estimate of the present day concentration of BC while maintaining their estimated present day global spatial and vertical distribution. The top of the atmosphere (TOA) radiative forcing of BC in these experiments is positive (warming) and increases linearly as the BC burden increases. The total semi-direct effect for the 1x experiment is positive but becomes increasingly negative for higher BC concentrations. The global average surface temperature response is found to be a linear function of the TOA radiative forcing. The climate sensitivity to BC from these experiments is estimated to be 0.42 K $\\textnormal W^{-1} m^{2}$ when the semi-direct effects are accounted for and 0.22 K $\\textnormal W^{-1} m^{2}$ with only the direct effects considered. Global average precipitation decreases linearly as BC increases, with a precipitation sensitivity to atmospheric absorption of 0.4 $\\%$ $\\textnormal W^{-1} \\textnormal m^{2}$ . The hemispheric asymmetry of BC also causes an increase in southward cross-equatorial heat transport and a resulting northward shift of the inter-tropical convergence zone in the simulations at a rate of 4$^{\\circ}$N $\\textnormal PW^{-1}$. Global average mid- and high-level clouds decrease, whereas the low-level clouds increase linearly with BC. The increase in marine stratocumulus cloud fraction over the south tropical Atlantic is caused by increased BC-induced diabatic heating of the free troposphere.

Mahajan, Salil [ORNL; Evans, Katherine J [ORNL; Hack, James J [ORNL; Truesdale, John [National Center for Atmospheric Research (NCAR)

2013-01-01T23:59:59.000Z

125

Study of Mechanisms of Aerosol Indirect Effects on Glaciated Clouds: Progress during the Project Final Technical Report  

SciTech Connect

This 3-year project has studied how aerosol pollution influences glaciated clouds. The tool applied has been an 'aerosol-cloud model'. It is a type of Cloud-System Resolving Model (CSRM) modified to include 2-moment bulk microphysics and 7 aerosol species, as described by Phillips et al. (2009, 2013). The study has been done by, first, improving the model and then performing sensitivity studies with validated simulations of a couple of observed cases from ARM. These are namely the Tropical Warm Pool International Cloud Experiment (TWP-ICE) over the tropical west Pacific and the Cloud and Land Surface Interaction Campaign (CLASIC) over Oklahoma. During the project, sensitivity tests with the model showed that in continental clouds, extra liquid aerosols (soluble aerosol material) from pollution inhibited warm rain processes for precipitation production. This promoted homogeneous freezing of cloud droplets and aerosols. Mass and number concentrations of cloud-ice particles were boosted. The mean sizes of cloud-ice particles were reduced by the pollution. Hence, the lifetime of glaciated clouds, especially ice-only clouds, was augmented due to inhibition of sedimentation and ice-ice aggregation. Latent heat released from extra homogeneous freezing invigorated convective updrafts, and raised their maximum cloud-tops, when aerosol pollution was included. In the particular cases simulated in the project, the aerosol indirect effect of glaciated clouds was twice than of (warm) water clouds. This was because glaciated clouds are higher in the troposphere than water clouds and have the first interaction with incoming solar radiation. Ice-only clouds caused solar cooling by becoming more extensive as a result of aerosol pollution. This 'lifetime indirect effect' of ice-only clouds was due to higher numbers of homogeneously nucleated ice crystals causing a reduction in their mean size, slowing the ice-crystal process of snow production and slowing sedimentation. In addition to the known indirect effects (glaciation, riming and thermodynamic), new indirect effects were discovered and quantified due to responses of sedimentation, aggregation and coalescence in glaciated clouds to changing aerosol conditions. In summary, the change in horizontal extent of the glaciated clouds ('lifetime indirect effects'), especially of ice-only clouds, was seen to be of higher importance in regulating aerosol indirect effects than changes in cloud properties ('cloud albedo indirect effects').

Phillips, Vaughan T. J.

2013-10-18T23:59:59.000Z

126

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

SciTech Connect

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

127

ARM Aerosol Working Group Meeting  

NLE Websites -- All DOE Office Websites (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

128

ARM - Field Campaign - Carbonaceous Aerosol and Radiative Effects Study  

NLE Websites -- All DOE Office Websites (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)

129

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

130

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

131

Nuclear Reactor Severe Accident Experiments  

NLE Websites -- All DOE Office Websites (Extended Search)

Nuclear Reactor Severe Accident Experiments Nuclear Reactor Severe Accident Experiments Capabilities Engineering Experimentation Reactor Safety Testing and Analysis Overview Nuclear Reactor Severe Accident Experiments MAX NSTF SNAKE 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 Nuclear Reactor Severe Accident Experiments 1 2 3 4 5 6 7 We perform experiments simulating reactor core melt phenomena in which molten core debris ("corium") erodes the concrete floor of a containment building. This occurred during the Fukushima nuclear power plant accident though the extent of concrete damage is yet unknown. This video shows the top view of a churning molten pool of uranium oxide at 2000°C (3600°F) seen during an experiment at Argonne. Corium behaves much like lava.

132

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

133

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

134

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

135

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

136

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.

137

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.

138

Indirect and Semi-Direct Aerosol Campaign  

NLE Websites -- All DOE Office Websites (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.

139

Researchers Model Impact of Aerosols Over California  

NLE Websites -- All DOE Office Websites (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.

140

Aerodynamic Focusing Of High-Density Aerosols  

SciTech Connect

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

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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.


141

Modeling LIDAR Detection of Biological Aerosols to Determine Optimum Implementation Strategy  

SciTech Connect

This report summarizes work performed for a larger multi-laboratory project named the Background Interferent Measurement and Standards project. While originally tasked to develop algorithms to optimize biological warfare agent detection using UV fluorescence LIDAR, the current uncertainties in the reported fluorescence profiles and cross sections the development of any meaningful models. It was decided that a better approach would be to model the wavelength-dependent elastic backscattering from a number of ambient background aerosol types, and compare this with that generated from representative sporulated and vegetative bacterial systems. Calculations in this report show that a 266, 355, 532 and 1064 nm elastic backscatter LIDAR experiment will allow an operator to immediately recognize when sulfate, VOC-based or road dust (silicate) aerosols are approaching, independent of humidity changes. It will be more difficult to distinguish soot aerosols from biological aerosols, or vegetative bacteria from sporulated bacteria. In these latter cases, the elastic scattering data will most likely have to be combined with UV fluorescence data to enable a more robust categorization.

Sheen, David M.; Aker, Pam M.

2007-09-19T23:59:59.000Z

142

Spent fuel sabotage test program, characterization of aerosol dispersal : technical review and analysis supplement.  

SciTech Connect

This project seeks to provide vital data required to assess the consequences of a terrorist attack on a spent fuel transportation cask. One such attack scenario involves the use of conical shaped charges (CSC), which are capable of damaging a spent fuel transportation cask. In the event of such an attack, the amount of radioactivity that may be released as respirable aerosols is not known with great certainty. Research to date has focused on measuring the aerosol release from single short surrogate fuel rodlets subjected to attack by a small CSC device in various aerosol chamber designs. The last series of three experiments tested surrogate fuel rodlets made with depleted uranium oxide ceramic pellets in a specially designed double chamber aerosol containment apparatus. This robust testing apparatus was designed to prevent any radioactive release and allow high level radioactive waste disposal of the entire apparatus following testing of actual spent fuel rodlets as proposed. DOE and Sandia reviews of the project to date identified a number of issues. The purpose of this supplemental report is to address and document the DOE review comments and to resolve the issues identified in the Sandia technical review.

Durbin, Samuel G.; Lindgren, Eric Richard

2009-07-01T23:59:59.000Z

143

Near real time vapor detection and enhancement using aerosol adsorption  

SciTech Connect

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

144

Technical Note: Estimating Aerosol Effects on Cloud Radiative Forcing  

SciTech Connect

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

145

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

146

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

147

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

148

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

SciTech Connect

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

149

Understanding Brown Carbon Aerosols and Their Role in Climate Change  

NLE Websites -- All DOE Office Websites (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

150

Response of California temperature to regional anthropogenic aerosol  

NLE Websites -- All DOE Office Websites (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.

151

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

SciTech Connect

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

152

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

153

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

154

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

155

ADEPT. aerosol deposition in cylindrical pipes  

SciTech Connect

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

156

ADEPT. Aerosol Deposition in Cylindrical Pipes  

SciTech Connect

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

157

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

158

Inter-Comparison and Synergy Between the Two Long-Term Gloval Aerosol Products Derived from AVHRR and TOMS  

NLE Websites -- All DOE Office Websites (Extended Search)

Inter-Comparison and Synergy Between the Inter-Comparison and Synergy Between the Two Long-Term Global Aerosol Products Derived from AVHRR and TOMS M.-J. Jeong and Z. Li Department of Meteorology University of Maryland College Park, Maryland D. A. Chu and S.-C. Tsay National Aeronautics and Space Administration Goddard Flight Center Greenbelt, Maryland Introduction Eighteen years of satellite-based monthly aerosol products have been derived from the advanced very high resolution radiometer (AVHRR) and total ozone mapping experiment spectrometer (TOMS) sensors. The two products differ in many regards rendering a great potential for developing an integrated product for climate studies. Presented here are some preliminary results of inter-comparison and synergy analyses. Global Aerosol Climatology

159

Inter-annual Tropospheric Aerosol Variability in Late Twentieth Century and its Impact on Tropical Atlantic and West African Climate by Direct and Semi-direct Effects  

SciTech Connect

A new high-resolution (0.9$^{\\circ}$x1.25$^{\\circ}$ in the horizontal) global tropospheric aerosol dataset with monthly resolution is generated using the finite-volume configuration of Community Atmosphere Model (CAM4) coupled to a bulk aerosol model and forced with recent estimates of surface emissions for the latter part of twentieth century. The surface emissions dataset is constructed from Coupled Model Inter-comparison Project (CMIP5) decadal-resolution surface emissions dataset to include REanalysis of TROpospheric chemical composition (RETRO) wildfire monthly emissions dataset. Experiments forced with the new tropospheric aerosol dataset and conducted using the spectral configuration of CAM4 with a T85 truncation (1.4$^{\\circ}$x1.4$^{\\circ}$) with prescribed twentieth century observed sea surface temperature, sea-ice and greenhouse gases reveal that variations in tropospheric aerosol levels can induce significant regional climate variability on the inter-annual timescales. Regression analyses over tropical Atlantic and Africa reveal that increasing dust aerosols can cool the North African landmass and shift convection southwards from West Africa into the Gulf of Guinea in the spring season in the simulations. Further, we find that increasing carbonaceous aerosols emanating from the southwestern African savannas can cool the region significantly and increase the marine stratocumulus cloud cover over the southeast tropical Atlantic ocean by aerosol-induced diabatic heating of the free troposphere above the low clouds. Experiments conducted with CAM4 coupled to a slab ocean model suggest that present day aerosols can shift the ITCZ southwards over the tropical Atlantic and can reduce the ocean mixed layer temperature beneath the increased marine stratocumulus clouds in the southeastern tropical Atlantic.

Evans, Katherine J [ORNL; Hack, James J [ORNL; Truesdale, John [National Center for Atmospheric Research (NCAR); Mahajan, Salil [ORNL; Lamarque, J-F [University Center for Atmospheric Research

2012-01-01T23:59:59.000Z

160

Direct and semidirect aerosol effects of Southern African biomass burning aerosol  

SciTech Connect

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

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

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.

162

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

NLE Websites -- All DOE Office Websites (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

163

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

NLE Websites -- All DOE Office Websites (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

164

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

NLE Websites -- All DOE Office Websites (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

165

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

166

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

167

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

168

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.

169

Priorities for In-situ Aerosol Measurements  

NLE Websites -- All DOE Office Websites (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

170

Aerosol and graphitic carbon content of snow  

SciTech Connect

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

171

On The Importance of Organic Oxygen for Understanding Organic Aerosol  

NLE Websites -- All DOE Office Websites (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

172

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

173

ARM AOS Processing Status and Aerosol Intensive Properties VAP  

NLE Websites -- All DOE Office Websites (Extended Search)

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

174

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

NLE Websites -- All DOE Office Websites (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...

175

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

NLE Websites -- All DOE Office Websites (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...

176

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

177

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

NLE Websites -- All DOE Office Websites (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,...

178

aerosol influenza transmission: Topics by E-print Network  

NLE Websites -- All DOE Office Websites (Extended Search)

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

179

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

NLE Websites -- All DOE Office Websites (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...

180

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

NLE Websites -- All DOE Office Websites (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...

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

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

NLE Websites -- All DOE Office Websites (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,...

182

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

NLE Websites -- All DOE Office Websites (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......

183

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

184

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

NLE Websites -- All DOE Office Websites (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...

185

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

NLE Websites -- All DOE Office Websites (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)...

186

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

NLE Websites -- All DOE Office Websites (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...

187

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

NLE Websites -- All DOE Office Websites (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...

188

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...

189

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

NLE Websites -- All DOE Office Websites (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 <>...

190

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

191

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

NLE Websites -- All DOE Office Websites (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...

192

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

NLE Websites -- All DOE Office Websites (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

193

Development and Characterization of a Thermodenuder for Aerosol Volatility Measurements  

SciTech Connect

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

194

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

SciTech Connect

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

195

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

196

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

197

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

198

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

199

Determination of vertical profiles of aerosol extinction, single scatter  

NLE Websites -- All DOE Office Websites (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

200

ARM - Field Campaign - MArine Stratus Radiation Aerosol and Drizzle  

NLE Websites -- All DOE Office Websites (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

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201

Aerosol Retrievals under Partly Cloudy Conditions: Challenges and Perspectives  

SciTech Connect

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

202

Do Diurnal Aerosol Changes Affect Daily Average Radiative Forcing?  

SciTech Connect

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

203

Atmospheric aerosol monitoring at the Pierre Auger Observatory  

SciTech Connect

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

204

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

205

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

206

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

207

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

SciTech Connect

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

208

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

209

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

210

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

211

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.

212

Hyperspectral Aerosol Optical Depths from TCAP Flights  

SciTech Connect

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

213

Sulfate aerosols and polar stratospheric cloud formation  

SciTech Connect

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

214

The dependence of ice microphysics on aerosol concentration in arctic mixed-phase stratus clouds during ISDAC and M-PACE  

SciTech Connect

Cloud and aerosol data acquired by the National Research Council of Canada (NRC) Convair-580 aircraft in, above, and below single-layer arctic stratocumulus cloud during the Indirect and Semi-Direct Aerosol Campaign (ISDAC) in April 2008 were used to test three aerosol indirect effects hypothesized to act in mixed-phase clouds: the riming indirect effect, the glaciation indirect effect, and the cold second indirect effect. The data showed a correlation of R= 0.75 between liquid drop number concentration, Nliq, inside cloud and ambient aerosol number concentration NPCASP below cloud. This, combined with increasing liquid water content LWC with height above cloud base and the nearly constant profile of Nliq, suggested that liquid drops were nucleated from aerosol at cloud base. No strong evidence of a riming indirect effect was observed, but a strong correlation of R = 0.69 between ice crystal number concentration Ni and NPCASP above cloud was noted. Increases in ice nuclei (IN) concentration with NPCASP above cloud combined with the subadiabatic LWC profiles suggest possible mixing of IN from cloud top consistent with the glaciation indirect effect. The higher Nice and lower effective radius rel for the more polluted ISDAC cases compared to data collected in cleaner single-layer stratocumulus conditions during the Mixed-Phase Arctic Cloud Experiment is consistent with the operation of the cold second indirect effect. However, more data in a wider variety of meteorological and surface conditions, with greater variations in aerosol forcing, are required to identify the dominant aerosol forcing mechanisms in mixed-phase arctic clouds.

Jackson, Robert C.; McFarquhar, Greg; Korolev, Alexei; Earle, Michael; Liu, Peter S.; Lawson, R. P.; Brooks, Sarah D.; Wolde, Mengistu; Laskin, Alexander; Freer, Matthew

2012-08-14T23:59:59.000Z

215

The Two-Column Aerosol Project (TCAP) Science Plan  

SciTech Connect

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

216

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

SciTech Connect

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

217

Resuspension studies at Bikini Atoll. [Pulmonary exposure from dust-borne plutonium aerosols  

SciTech Connect

The following experiments were conducted on Bikini Atoll to provide key parameters for an assessment of inhalation exposure from plutonium-contaminated dust aerosols: (1) a characterization of background (plutonium activity, dust, plutonium, sea spray, and organic aerosol concentrations); (2) a study of plutonium resuspension from a bare field; (3) a study of plutonium resuspension by traffic; and (4) a study of personal inhalation exposure. Dust concentrations of 21 ..mu..g m/sup -3/ and sea spray of 34 ..mu..g m/sup -3/ were the background throughout the Bikini Island except within 50 m of the windward beach. Background concentrations of /sup 239 +240/Pu were 60 aCi m/sup -3/ in the coconut grove and 264 aCi m/sup -3/ over rain-stabilized bare soil. The ratio of plutonium activity in aerosols relative to the activity in underlying soil, defined as the enhancement factor, EF, was typically less than one. Enhancement factors increased about 3.8 as a result of tilling. Plutonium resuspension flux was estimated at 0.49 pCi m/sup -2/ year/sup -1/ over most of Bikini Island. Aerosol size distributions associated with mass and with plutonium activity were typically log-normal with median aerodynamic diameter 2.44 ..mu..m, which decreased to 2.0 ..mu..m above freshly tilled soil. The Pu concentration in aerosols collected over disturbed soil increased by a factor of 19.1. Vehicular traffic produced dust pulses typically of 10 s duration, 28 ..mu..g m/sup -3/ average concentration, and plutonium enhancement factor 2.5. Personal dosimetry showed that enhancement of dust by a worker was a factor of 2.64 for heavy work outdoors and 1.86 for light work in and around houses. Pulmonary deposition of plutonium was calculated for various exposure conditions. The pulmonary deposition ranged from 1476 aCi h/sup -1/ to 12 aCi h/sup -1/ with intermediate values for heavy outdoor work and for light work in and around houses.

Shinn, J.H.; Homan, D.N.; Robison, W.L.

1980-02-01T23:59:59.000Z

218

Impact of natural and anthropogenic aerosols on stratocumulus and precipitation in the Southeast Pacific: A regional modeling study using WRF-Chem  

SciTech Connect

Cloud-system resolving simulations with the chemistry version of the Weather Research and Forecasting (WRF-Chem) model are used to quantify the impacts of regional anthropogenic and oceanic emissions on changes in aerosol properties, cloud macro- and microphysics, and cloud radiative forcing over the Southeast Pacific (SEP) during the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) (15 OctNov 16, 2008). The effects of oceanic aerosols on cloud properties, precipitation, and the shortwave forcing counteract those of anthropogenic aerosols. Despite the relatively small changes in Na concentrations (2-12%) from regional oceanic emissions, their net effect (direct and indirect) on the surface shortwave forcing is opposite and comparable or even larger in magnitude compared to those of regional anthropogenic emissions over the SEP. Two distinct regions are identified in the VOCALS-REx domain. The near-coast polluted region is characterized with strong droplet activation suppression of small particles by sea-salt particles, the more important role of the first than the second indirect effect, low surface precipitation rate, and low aerosol-cloud interaction strength associated with anthropogenic emissions. The relatively clean remote region is characterized with large contributions of Cloud Condensation Nuclei (CCN, number concentration denoted by NCCN) and droplet number concentrations (Nd) from non-local sources (lateral boundaries), a significant amount of surface precipitation, and high aerosol-cloud interactions under a scenario of five-fold increase in anthropogenic emissions. In the clean region, cloud properties have high sensitivity (e.g., 13% increase in cloud-top height and a 9% surface albedo increase) to the moderate increase in CCN concentration (?Nccn = 13 cm-3; 25%) produced by a five-fold increase in regional anthropogenic emissions. The increased anthropogenic aerosols reduce the precipitation amount over the relatively clean remote ocean. The reduction of precipitation (as a cloud water sink) more than doubles the wet scavenging timescale, resulting in an increased aerosol lifetime in the marine boundary layer. Therefore, the aerosol impacts on precipitation are amplified by the positive feedback of precipitation on aerosol. The positive feedback ultimately alters the cloud micro- and macro-properties, leading to strong aerosol-cloud-precipitation interactions. The higher sensitivity of clouds to anthropogenic aerosols over this region is also related to a 16% entrainment rate increase due to anthropogenic aerosols. The simulated aerosol-cloud-precipitation interactions are stronger at night over the clean marine region, while during the day, solar heating results in more frequent decoupling, thinner clouds, reduced precipitation, and reduced sensitivity to anthropogenic emissions. The simulated high sensitivity to the increased anthropogenic emissions over the clean region suggests that the perturbation of the clean marine environment with anthropogenic aerosols may have a larger effect on climate than that of already polluted marine environments.

Yang, Qing; Gustafson, William I.; Fast, Jerome D.; Wang, Hailong; Easter, Richard C.; Wang, Minghuai; Ghan, Steven J.; Berg, Larry K.; Leung, Lai-Yung R.; Morrison, H.

2012-09-28T23:59:59.000Z

219

Aerosol-Based Duct Sealing Technology  

NLE Websites -- All DOE Office Websites (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

220

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

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

Discrimination between thin cirrus and and tropospheric aerosol using  

NLE Websites -- All DOE Office Websites (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

222

Mobile Climate Observatory for Atmospheric Aerosols in India  

NLE Websites -- All DOE Office Websites (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

223

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

224

A New Assessment of the Aerosol First Indirect Effect  

NLE Websites -- All DOE Office Websites (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

225

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

226

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

NLE Websites -- All DOE Office Websites (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...

227

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

NLE Websites -- All DOE Office Websites (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...

228

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

NLE Websites -- All DOE Office Websites (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...

229

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

NLE Websites -- All DOE Office Websites (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...

230

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

231

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

232

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.

233

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

234

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

235

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

236

Continuous air monitor for alpha-emitting aerosol particles  

SciTech Connect

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

237

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

238

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

239

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

240

Atmospheric Aerosol Chemistry, Climate Change, and Air Quality  

NLE Websites -- All DOE Office Websites (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...

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

ARM - Field Campaign - Shortwave Radiation and Aerosol Intensive  

NLE Websites -- All DOE Office Websites (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.

242

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

SciTech Connect

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

243

A Numerical Sensitivity Study of Aerosol Influence on Immersion Freezing  

NLE Websites -- All DOE Office Websites (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

244

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

245

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

SciTech Connect

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

246

On modification of global warming by sulfate aerosols  

SciTech Connect

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

247

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

248

An Aerosol Condensation Model for Sulfur Trioxide  

SciTech Connect

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

249

Combustion aerosols formed during burning of radioactively contaminated materials: Experimental results  

SciTech Connect

Safety assessments and environmental impact statements for nuclear fuel cycle facilities require an estimate of potential airborne releases. Radioactive aerosols generated by fires were investigated in experiments in which combustible solids and liquids were contaminated with radioactive materials and burned. Uranium in powder and liquid form was used to contaminate five fuel types: polychloroprene, polystyrene, polymethylmethacrylate, cellulose, and a mixture of 30% tributylphosphate (TBP) in kerosene. Heat flux, oxygen concentration, air flow, contaminant concentration, and type of ignition were varied in the experiments. The highest release (7.1 wt %) came from burning TBP/kerosene over contaminated nitric acid. Burning cellulose contaminated with uranyl nitrate hexahydrate liquid gave the lowest release (0.01 wt %). Rate of release and particle size distribution of airborne radioactive particles were highly dependent on the type of fuel burned.

Halverson, M.A.; Ballinger, M.Y.; Dennis, G.W.

1987-03-01T23:59:59.000Z

250

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

251

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

SciTech Connect

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

252

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

NLE Websites -- All DOE Office Websites (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...

253

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

254

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

255

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

NLE Websites -- All DOE Office Websites (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...

256

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

257

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

258

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

259

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

260

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

NLE Websites -- All DOE Office Websites (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...

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

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

262

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

263

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

264

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

265

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

NLE Websites -- All DOE Office Websites (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...

266

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

267

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

268

Parameterizations of Cloud Microphysics and Indirect Aerosol Effects  

SciTech Connect

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

269

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

SciTech Connect

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

270

Ignition Experiments  

NLE Websites -- All DOE Office Websites (Extended Search)

Ignition Experiments The goal of many NIF experiments is to create a self-sustaining "burn" of fusion fuel (the hydrogen isotopes deuterium and tritium) that produces as much or...

271

CARES: Carbonaceous Aerosol and Radiative Effects Study Operations Plan  

SciTech Connect

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

272

Aerosol Data Sources and Their Roles within PARAGON  

SciTech Connect

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

273

Calculating Capstone Depleted Uranium Aerosol Concentrations from Beta Activity Measurements  

SciTech Connect

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

274

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

275

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

276

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

NLE Websites -- All DOE Office Websites (Extended Search)

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

277

Characterization of Pre-Commercial Gasoline Engine Particulates Through Advanced Aerosol Methods  

Energy.gov (U.S. Department of Energy (DOE))

Advanced aerosol analysis methods were used to examine particulates from single cylinder test engines running on gasoline and ethanol blends.

278

Emissions of trace gases and aerosols during the open combustion of biomass  

NLE Websites -- All DOE Office Websites (Extended Search)

Emissions of trace gases and aerosols during the open combustion of biomass Emissions of trace gases and aerosols during the open combustion of biomass in the laboratory Title Emissions of trace gases and aerosols during the open combustion of biomass in the laboratory Publication Type Journal Article Year of Publication 2009 Authors McMeeking, Gavin R., Sonia M. Kreidenweis, Stephen Baker, Christian M. Carrico, Judith C. Chow, Jeffrey Collett L. Jr., Wei Min Hao, Amanda S. Holden, Thomas W. Kirchstetter, William C. Malm, Hans Moosmuller, Amy P. Sullivan, and Cyle E. Wold Journal Journal of Geophysical Research Volume 114 Abstract We characterized the gas- and speciated aerosol-phase emissions from the open combustion of 33 different plant species during a series of 255 controlled laboratory burns during the Fire Laboratory at Missoula Experiments (FLAME). The plant species we tested were chosen to improve the existing database for U.S. domestic fuels: laboratory-based emission factors have not previously been reported for many commonly burned species that are frequently consumed by fires near populated regions and protected scenic areas. The plants we tested included the chaparral species chamise, manzanita, and ceanothus, and species common to the southeastern United States (common reed, hickory, kudzu, needlegrass rush, rhododendron, cord grass, sawgrass, titi, and wax myrtle). Fire-integrated emission factors for gas-phase CO2, CO, CH4, C2-4 hydrocarbons, NH3, SO2, NO, NO2, HNO3, and particle-phase organic carbon (OC), elemental carbon (EC), SO4 2, NO3, Cl, Na+, K+, and NH4 + generally varied with both fuel type and with the fire-integrated modified combustion efficiency (MCE), a measure of the relative importance of flaming- and smoldering-phase combustion to the total emissions during the burn. Chaparral fuels tended to emit less particulate OC per unit mass of dry fuel than did other fuel types, whereas southeastern species had some of the largest observed emission factors for total fine particulate matter. Our measurements spanned a larger range of MCE than prior studies, and thus help to improve estimates of the variation of emissions with combustion conditions for individual fuels.

279

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

280

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

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
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We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

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

282

Surface based remote sensing of aerosol-cloud interactions  

NLE Websites -- All DOE Office Websites (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

283

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

NLE Websites -- All DOE Office Websites (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

284

ARM - Evaluation Product - Aerosol Optical Depths from SASHE  

NLE Websites -- All DOE Office Websites (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

285

Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant Particles  

NLE Websites -- All DOE Office Websites (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

286

Direct Aerosol Forcing in the Infrared at the SGP Site?  

NLE Websites -- All DOE Office Websites (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

287

Lognormal Size Distribution Theory for Deposition of Polydisperse Aerosol Particles  

SciTech Connect

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

288

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

289

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

NLE Websites -- All DOE Office Websites (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

290

Airborne measurements of carbonaceous aerosols in southern Africa during  

NLE Websites -- All DOE Office Websites (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.

291

Sealing Ducts in Large Commercial Buildings with Aerosolized Sealant  

NLE Websites -- All DOE Office Websites (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.

292

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

293

Final Project Report - ARM CLASIC CIRPAS Twin Otter Aerosol  

SciTech Connect

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

294

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

295

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

296

Digestion Experiments  

E-Print Network (OSTI)

Blank in Bulletin] BULLETIN NO. 291 FEBRUARY, 1922 DIGESTION EXPERIMENTS This is the sixth bulletin in a series whose object is to ascertain the Aceding value of Texas feeding stuffs by means of digestion experiments. Previous bulletins... The productive values and the values for digestible protein in t Bulletin have been calculated from the results of digestion esperiine? with sheep. The method of conducting the experiments is described Bulletins Nos. 147 and 166 of this Station. The production...

Fraps, G. S. (George Stronach)

1922-01-01T23:59:59.000Z

297

Long-term Statistics of Continental Cumuli: Does Aerosol Trigger Cumulus Variability?  

SciTech Connect

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

298

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

299

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

SciTech Connect

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

300

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

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

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.

302

Soft ionization of thermally evaporated hypergolic ionic liquid aerosols  

SciTech Connect

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

303

Building America Webinar: Sealing of Home Enclosures with Aerosol Particles  

Energy.gov (U.S. Department of Energy (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.

304

LESSONS LEARNED IN AEROSOL MONITORING WITH THE RASA  

SciTech Connect

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

305

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

306

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

307

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

308

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

309

Correction to Hyperspectral Aerosol Optical Depths from TCAP Flights  

SciTech Connect

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

310

Hydronuclear experiments  

SciTech Connect

Hydronuclear experiments, a method for assessing some aspects of nuclear weapon safety, were conducted at Los Alamos during the 1958 to 1961 moratorium on nuclear testing. The experiments resulted in subcritical multiplying assemblies or a very slight degree of supercriticality and, in some cases, involved a slight, but insignificant, fission energy release. These experiments helped to identify so-called one-point safety problems associated with some of the nuclear weapons systems of that time. The need for remedial action was demonstrated, although some of the necessary design changes could not be made until after the resumption of weapons testing at the end of 1961.

Thorn, R.N.; Westervelt, D.R.

1987-02-01T23:59:59.000Z

311

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

312

A Physically Based Framework for Modelling the Organic Fractionation of Sea Spray Aerosol from Bubble Film Langmuir Equilibria  

SciTech Connect

The presence of a large fraction of organic matter in primary sea spray aerosol (SSA) can strongly affect its cloud condensation nuclei activity and interactions with marine clouds. Global climate models require new parameterizations of the SSA composition in order to improve the representation of these processes. Existing proposals for such a parameterization use remotely-sensed chlorophyll-a concentrations as a proxy for the biogenic contribution to the aerosol. However, both observations and theoretical considerations suggest that existing relationships with chlorophyll-a, derived from observations at only a few locations, may not be representative for all ocean regions. We introduce a novel framework for parameterizing the fractionation of marine organic matter into SSA based on a competitive Langmuir adsorption equilibrium at bubble surfaces. Marine organic matter is partitioned into classes with differing molecular weights, surface excesses, and Langmuir adsorption parameters. The classes include a lipid-like mixture associated with labile dissolved organic carbon (DOC), a polysaccharide-like mixture associated primarily with semi-labile DOC, a protein-like mixture with concentrations intermediate between lipids and polysaccharides, a processed mixture associated with recalcitrant surface DOC, and a deep abyssal humic-like mixture. Box model calculations have been performed for several cases of organic adsorption to illustrate the underlying concepts. We then apply the framework to output from a global marine biogeochemistry model, by partitioning total dissolved organic carbon into several classes of macromolecule. Each class is represented by model compounds with physical and chemical properties based on existing laboratory data. This allows us to globally map the predicted organic mass fraction of the nascent submicron sea spray aerosol. Predicted relationships between chlorophyll-\\textit{a} and organic fraction are similar to existing empirical parameterizations, but can vary between biologically productive and non-productive regions, and seasonally within a given region. Major uncertainties include the bubble film thickness at bursting and the variability of organic surfactant activity in the ocean, which is poorly constrained. In addition, marine colloids and cooperative adsorption of polysaccharides may make important contributions to the aerosol, but are not included here. This organic fractionation framework is an initial step towards a closer linking of ocean biogeochemistry and aerosol chemical composition in Earth system models. Future work should focus on improving constraints on model parameters through new laboratory experiments or through empirical fitting to observed relationships in the real ocean and atmosphere, as well as on atmospheric implications of the variable composition of organic matter in sea spray.

Burrows, Susannah M.; Ogunro, O.; Frossard, Amanda; Russell, Lynn M.; Rasch, Philip J.; Elliott, S.

2014-12-19T23:59:59.000Z

313

FY 2011 Second Quarter: Demonstration of New Aerosol Measurement Verification Testbed for Present-Day Global Aerosol Simulations  

SciTech Connect

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

314

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

NLE Websites -- All DOE Office Websites (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

315

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

NLE Websites -- All DOE Office Websites (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

316

Importance of Iron Mineralogy to Aerosol Solubility: Potential Effects of  

NLE Websites -- All DOE Office Websites (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

317

Observations of the first aerosol indirect effect in shallow cumuli  

SciTech Connect

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

318

Enhancement factors for resuspended aerosol radioactivity: Effects of topsoil disturbance  

SciTech Connect

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

319

Laboratory Testing of Aerosol for Enclosure Air Sealing  

SciTech Connect

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

320

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

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

Emplacing experience  

Science Journals Connector (OSTI)

We propose that understandings of the role of space and place in everyday life are of value to designing the environment of Role Playing Games (RPGs). We compare aspects of space and place in spatial experiences while moving through terrains in physical ... Keywords: place, space, video games

David Browning; Steven Stanley; Michael Fryer; Nicola J Bidwell

2006-12-01T23:59:59.000Z

322

Thermophoresis and its thermal parameters for aerosol collection  

NLE Websites -- All DOE Office Websites (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

323

Large historical changes of fossil-fuel black carbon aerosols  

SciTech Connect

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

324

Aerosol-Derived Bimetallic Alloy Powders: Bridging the Gap  

SciTech Connect

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

325

Quantifying the Aerosol Indirect Effect Using Ground-Based Remote Sensors and Models  

NLE Websites -- All DOE Office Websites (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.

326

E-Print Network 3.0 - aerosol mass spectrometry Sample Search...  

NLE Websites -- All DOE Office Websites (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......

327

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

328

E-Print Network 3.0 - aerosol measurements importance Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

38 Absorbing aerosols and pre-summer monsoon hydroclimate variability over the Indian subcontinent: The challenge in investigating links Summary: for the importance of...

329

Single particle characterization, source apportionment, and aging effects of ambient aerosols in Southern California  

E-Print Network (OSTI)

of scale, in Air Pollution and Health in Rapidly Developingfor particulate air pollution health standards, Aerosolfor particulate air pollution health standards, Aerosol

Shields, Laura Grace

2008-01-01T23:59:59.000Z

330

NASA multipurpose airborne DIAL system and measurements of ozone and aerosol profiles  

Science Journals Connector (OSTI)

An airborne differential absorption lidar (DIAL) system has been developed for the remote measurement of gas and aerosol profiles in the troposphere and lower stratosphere. The...

Browell, E V; Carter, A F; Shipley, S T; Allen, R J; Butler, C F; Mayo, M N; Siviter, J H; Hall, W M

1983-01-01T23:59:59.000Z

331

E-Print Network 3.0 - aerosol program program Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

CHAPSCLASIC Summary: Observations of Cloud-Aerosol Halos During CHAPSCLASIC Funded by NASA HQ Science Mission... Directorate Radiation Sciences Program Funded by Department of...

332

E-Print Network 3.0 - ammonium nitrate aerosols Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

ON MINERAL DUSTS: CRYSTALLINE OR AQUEOUS? Summary: 02138, USA Keywords: Phase transition; Atmospheric Aerosols; Ammonium sulfate; Ammonium nitrate... that of ammonium...

333

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

334

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

NLE Websites -- All DOE Office Websites (Extended Search)

Big Influence... Aerosols play an important role in our planet's dynamic ... Source: Jet Propulsion Laboratory, Machine Learning Systems Group Collection: Computer Technologies...

335

Do biomass burning aerosols intensify drought in equatorial Asia during El Nio?  

E-Print Network (OSTI)

fication of drought-induced biomass burning in Indonesiavariability in global biomass burning emissions from 1997 toChemistry and Physics Do biomass burning aerosols intensify

Tosca, M. G; Randerson, J. T; Zender, C. S; Flanner, M. G; Rasch, P. J

2010-01-01T23:59:59.000Z

336

E-Print Network 3.0 - aerosol features biomass Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

features biomass Search Powered by Explorit Topic List Advanced Search Sample search results for: aerosol features biomass Page: << < 1 2 3 4 5 > >> 1 Global observations and...

337

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

NLE Websites -- All DOE Office Websites (Extended Search)

of Applied Science Collection: Environmental Sciences and Ecology 3 Arctic-Winter Climatology and Radiative Effects of Clouds and Aerosols Based on Lidar and Radar Measurements...

338

E-Print Network 3.0 - aerosol detection equipment Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

<< < 1 2 3 4 5 > >> 1 Assessing Goddard Institute for Space Studies ModelE aerosol climatology using satellite and ground-based measurements Summary: Assessing Goddard Institute...

339

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

NLE Websites -- All DOE Office Websites (Extended Search)

the ocean and the dynamic nature of aerosol inputs, this topic... alteration during transport). Before we can reliably model ... Source: Paytan, Adina - Department of Earth...

340

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

NLE Websites -- All DOE Office Websites (Extended Search)

are also directly associated with reduction in visibility and with long-range transport... for atmospheric aerosols is their association ... Source: Brookhaven National...

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

E-Print Network 3.0 - aerosol depletion test Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

depletion test Search Powered by Explorit Topic List Advanced Search Sample search results for: aerosol depletion test Page: << < 1 2 3 4 5 > >> 1 Supervolcanoes General feedback...

342

E-Print Network 3.0 - aerosolized brain natriuretic Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

brain natriuretic Search Powered by Explorit Topic List Advanced Search Sample search results for: aerosolized brain natriuretic Page: << < 1 2 3 4 5 > >> 1 JOURNAL OF EXPERIMENTAL...

343

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

NLE Websites -- All DOE Office Websites (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:...

344

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

SciTech Connect

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

345

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

346

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

NLE Websites -- All DOE Office Websites (Extended Search)

American Chemical... Element Methods, Aerosols, Air Pollution Modeling, ... Source: Consortium for Fossil Fuel Science, C1 Chemistry Program Collection: Fossil Fuels 36...

347

E-Print Network 3.0 - annually occurring aerosol Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

in Radiative Transfer Encyclopedia of Atmospheric Science Summary: system. Naturally occurring aerosols reflect some of the incident solar radiation back to space before... in...

348

Strong radiative heating due to the mixing state of black carbon in atmospheric aerosols  

Science Journals Connector (OSTI)

... The global model that I used was GATOR-GCMM, which treated gas, aerosol, radiative, meteorological and transport processes (see Supplementary ...

Mark Z. Jacobson

2001-02-08T23:59:59.000Z

349

Year Report (FY 2000) Evaluation of uncertainties in satellite retrievals of aerosol  

E-Print Network (OSTI)

. Third Year Statement of Work 1. Construct clean aerosol data sets for the Mauna Loa (Hawaii), and Cheeka retrievals to the observed variability of ae

350

E-Print Network 3.0 - aerosol wastes Sample Search Results  

NLE Websites -- All DOE Office Websites (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... ,...

351

Single particle characterization, source apportionment, and aging effects of ambient aerosols in Southern California  

E-Print Network (OSTI)

of levoglucosan in biomass combustion aerosol by high-and differences in biomass combustion smoke under differentwere unique to biomass combustion. Finally, the relative

Shields, Laura Grace

2008-01-01T23:59:59.000Z

352

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

NLE Websites -- All DOE Office Websites (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...

353

E-Print Network 3.0 - aerosol monitoring Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Dodd Way, Atlanta, GA, 30332, U.S.A. Abstract. Atmospheric aerosols scatter and absorb solar Source: Bergin, Mike - Schools of Civil and Environmental Engineering & Earth and...

354

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

NLE Websites -- All DOE Office Websites (Extended Search)

Imaging Spectroradiometer observations: Top-of-atmosphere albedo change Summary: Panel on Climate Change, 2007. Aerosol particles have a variety of shapes, sizes, and...

355

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

NLE Websites -- All DOE Office Websites (Extended Search)

October 4, 2004 Abstract Atmospheric aerosol particles scatter and absorb shortwave (solar) radiation and... of the U.S. Department of Energy under Contract No....

356

E-Print Network 3.0 - atmospheric aerosols basic Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

SIZE DISTRIBUTION Brookhaven National Laboratory is a multi... analyzers due to its speed and ability to detect aerosol particles smaller than 100 nm in diameter ... Source:...

357

Turbulent mixing in ducts, theory and experiment application to aerosol single point sampling  

E-Print Network (OSTI)

straight duct, 900 elbow, 450 lateral and a generic mixer are incorporated into a correlation model for predicting the mixing quality for both the velocity and contaminant concentration as functions of such flow geometry, scale, pressure drop and fluid...

Langari, Abdolreza

2012-06-07T23:59:59.000Z

358

DOE/SC-ARM-14-011 Ganges Valley Aerosol Experiment (GVAX) Final...  

NLE Websites -- All DOE Office Websites (Extended Search)

KK Moorthy, and VR Kotamarthi. 2013. "Validation of the online chemistry transport model WRF-CHEM over Indian region." Journal of Geophysical Research. Submitted. Kotamarthi, VR,...

359

Impact of aerosols present in Titan's atmosphere on the CASSINI radar experiment  

E-Print Network (OSTI)

of interest for Titan: liquid methane, liquid mixture of methane-ethane, water ice and light hydrocarbon ices. This chemistry results in the production of a great diversity of hydrocarbons and nitriles in the stratosphere-visible-NIR wavelengths. It is also possible that lighter hydrocarbons or nitriles diffuse downwards and condense

Boyer, Edmond

360

Fire-protection research for energy technology: FY 80 year-end report. [For fusion energy experiments and other energy research  

SciTech Connect

This continuing research program was initiated in 1977 in order to advance fire protection strategies for Fusion Energy Experiments (FEE). The program has since been expanded to encompass other forms of energy research. Accomplishments for fiscal year 1980 were: finalization of the fault-tree analysis of the Shiva fire management system; development of a second-generation, fire-growth analysis using an alternate moel and new LLNL combustion dynamics data; improvements of techniques for chemical smoke aerosol analysis; development and test of a simple method to assess the corrosive potential of smoke aerosols; development of an initial aerosol dilution system; completion of primary small-scale tests for measurements of the dynamics of cable fires; finalization of primary survey format for non-LLNL energy technology facilities; and studies of fire dynamics and aerosol production from electrical insulation and computer tape cassettes.

Hasegawa, H.K.; Alvares, N.J.; Lipska, A.E.; Ford, H.; Priante, S.; Beason, D.G.

1981-05-26T23:59:59.000Z

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

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

E-Print Network (OSTI)

, heterogeneous surface reactions, cloud processing, and gas-to-particle partitioning through the formation of secondary organic aerosol (SOA) by organic gases (Pankow 1994). Moreover, SOA has been linked to adverse health effects as they typically contain... 1985; Ng et al. 2006; Presto et al. 2005; Saathoff et al. 2003). Such classes include cycloalkenes, aromatic hydrocarbons, and terpenes, most of which are cyclic compounds. When these compounds undergo atmospheric oxidation, 3 they produce first-generation...

Glen, Crystal

2012-02-14T23:59:59.000Z

362

Chemical and Physical Properties of Atmospheric Aerosols (a) A Case Study in the Unique Properties of Agricultural Aerosols (b) The Role of Chemical Composition in Ice Nucleation during the Arctic Spring  

E-Print Network (OSTI)

dataset is reported for these physical and chemical properties of agricultural aerosols appropriate for use in a site-specific emission inventory. The emission rate and transport of the aerosols are also discussed. In addition, mixing ratios of total...

Moon, Seong-Gi

363

The impact of biogenic carbon emissions on aerosol absorption inMexico City  

SciTech Connect

In order to determine the wavelength dependence of atmospheric aerosol absorption in the Mexico City area, the absorption angstrom exponents (AAEs) were calculated from aerosol absorption measurements at seven wavelengths obtained with a seven-channel aethalometer during two field campaigns, the Mexico City Metropolitan Area study in April 2003 (MCMA 2003) and the Megacity Initiative: Local and Global Research Observations in March 2006 (MILAGRO). The AAEs varied from 0.76 to 1.56 in 2003 and from 0.54 to 1.52 in 2006. The AAE values determined in the afternoon were consistently higher than the corresponding morning values, suggesting the photochemical formation of absorbing secondary organic aerosols (SOA) in the afternoon. The AAE values were compared to stable and radiocarbon isotopic measurements of aerosol samples collected at the same time to determine the sources of the aerosol carbon. The fraction of modern carbon (fM) in the aerosol samples, as determined from {sup 14}C analysis, showed that 70% of the carbonaceous aerosols in Mexico City were from modern sources, indicating a significant impact from biomass burning during both field campaigns. The {sup 13}C/{sup 12}C ratios of the aerosol samples illustrate the significant impact of Yucatan forest fires (C-3 plants) in 2003 and local grass fires (C-4 plants) at site T1 in 2006. A direct comparison of the fM values, stable carbon isotope ratios, and calculated aerosol AAEs suggested that the wavelength dependence of the aerosol absorption was controlled by the biogenically derived aerosol components.

Marley, N; Gaffney, J; Tackett, M J; Sturchio, N; Hearty, L; Martinez, N; Hardy, K D; Machany-Rivera, A; Guilderson, T P; MacMillan, A; Steelman, K

2009-02-24T23:59:59.000Z

364

Importance of aerosol composition, mixing state, and morphology for heterogeneous ice nucleation: A combined field and laboratory approach  

E-Print Network (OSTI)

In this study chemical compositions of background aerosol and ice nuclei were examined through laboratory investigations using Raman spectroscopy and field measurements by single-particle mass spectrometry. Aerosol sampling ...

Baustian, Kelly J.

365

Formation of ozone and growth of aerosols in young smoke plumes from biomass burning: 1. Lagrangian parcel studies  

E-Print Network (OSTI)

We have developed a new model of the gas- and aerosol-phase chemistry of biomass burning smoke plumes called Aerosol Simulation Program (ASP). Here we use ASP combined with a Lagrangian parcel model to simulate the chemistry ...

Alvarado, Matthew James

366

Coupled Aerosol-ChemistryClimate Twentieth-Century Transient Model Investigation: Trends in Short-Lived Species and Climate Responses  

Science Journals Connector (OSTI)

The authors simulate transient twentieth-century climate in the Goddard Institute for Space Studies (GISS) GCM, with aerosol and ozone chemistry fully coupled to one another and to climate including a full dynamic ocean. Aerosols include sulfate, ...

Dorothy Koch; Susanne E. Bauer; Anthony Del Genio; Greg Faluvegi; Joseph R. McConnell; Surabi Menon; Ronald L. Miller; David Rind; Reto Ruedy; Gavin A. Schmidt; Drew Shindell

2011-06-01T23:59:59.000Z

367

Emerging Issues in Nanoparticle Aerosol Science and Technology Workshop report sponsored by: NSF, Southern California Particle Center and UCLA  

E-Print Network (OSTI)

has responsibility for nuclear reactor safety which includes emissions of radioactive particles pollution sources, (2) industrial production of nanoparticle reinforcing fillers such as carbon black nanoparticle products by aerosol processes, (4) atmospheric dynamics of fractal-like nanoparticle aerosols (e

Jimenez, Jose-Luis

368

Response of the NCAR Community Climate Model to the Radiative Forcing by the Naturally Occurring Tropospheric Aerosol  

Science Journals Connector (OSTI)

We insert the effect of naturally occurring tropospheric aerosols on solar radiation into the NCAR Community Climate Model (CCM). The effect of the aerosol depends on concentration and type (continental, maritime), surface albedo, solar zenith ...

James A. Coakley Jr.; Robert D. Cess

1985-08-01T23:59:59.000Z

369

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

370

Analysis of the causes of heavy aerosol pollution in Beijing, China: A case study with the WRF-Chem model  

Science Journals Connector (OSTI)

Abstract The causes and variability of a heavy haze episode in the Beijing region was analyzed. During the episode, the PM2.5 concentration reached a peak value of 450?g/kg on January 18, 2013 and rapidly decreased to 100?g/kg on January 19, 2013, characterizing a large variability in a very short period. This strong variability provides a good opportunity to study the causes of the haze formation. The in situ measurements (including surface meteorological data and vertical structures of the winds, temperature, humidity, and planetary boundary layer (PBL)) together with a chemical/dynamical regional model (WRF-Chem) were used for the analysis. In order to understand the rapid variability of the PM2.5 concentration in the episode, the correlation between the measured meteorological data (including wind speed, PBL height, relative humidity, etc.) and the measured particle concentration (PM2.5 concentration) was studied. In addition, two sensitive model experiments were performed to study the effect of individual contribution from local emissions and regional surrounding emissions to the heavy haze formation. The results suggest that there were two major meteorological factors in controlling the variability of the PM2.5 concentration, namely, surface wind speed and PBL height. During high wind periods, the horizontal transport of aerosol particles played an important role, and the heavy haze was formed when the wind speeds were very weak (less than 1m/s). Under weak wind conditions, the horizontal transport of aerosol particles was also weak, and the vertical mixing of aerosol particles played an important role. As a result, the PBL height was a major factor in controlling the variability of the PM2.5 concentration. Under the shallow PBL height, aerosol particles were strongly confined near the surface, producing a high surface PM2.5 concentration. The sensitivity model study suggests that the local emissions (emissions from the Beijing region only) were the major cause for the heavy haze events. With only local emissions, the calculated peak value of the PM2.5 concentration was 350?g/kg, which accounted for 78% of the measured peak value (450?g/kg). In contrast, without the local emissions, the calculated peak value of the PM2.5 concentration was only 100?g/kg, which accounted for 22% of the measured peak value.

Hui He; Xuexi Tie; Qiang Zhang; Xiange Liu; Qian Gao; Xia Li; Yang Gao

2014-01-01T23:59:59.000Z

371

AO02 -Aerosol Inlet Design Candidate 44263 Supervisor: Dr. Daniel Peters Word Count:3812  

E-Print Network (OSTI)

are suggested. A field test investigating the size distribution of tyre smoke aerosols from airplane landings is conducted using the suggested designs. No significant tyre smoke is observed despite the designs being of the aerosol must be drawn through an inlet and transported to the collection or mea- surement device

Oxford, University of

372

Direct and semi-direct radiative effects of anthropogenic aerosols in the Western United States: Seasonal  

E-Print Network (OSTI)

a regional climate model (RCM) in conjunction with the aerosol fields from a GEOS-Chem chemical- transport emissions and the seasonal low-level winds. The RCM-simulated anthropogenic aerosol radiative effects vary, respectively, following the seasonal AOD. In Arizona-New Mexico (AZNM), the effect of anthropogenic sulfates

Liou, K. N.

373

A Scalable Turbulent Mixing Aerosol Reactor for Oxide-Coated Silicon Nanoparticles  

E-Print Network (OSTI)

of Technology, 391 South Holliston Avenue, Pasadena, California 91125 A new, turbulent flow aerosol reactor. These composite nanoparticles were synthesized under clean conditions, deposited on 200 mm diameter silicon wafers aerosol technology is routinely integrated into microelectronics processing. Foremost is reluctance

Atwater, Harry

374

Comparison of coliphage and bacterial aerosols at a wastewater spray irrigation site.  

Science Journals Connector (OSTI)

...replaced by distilled water plus 0.1% Tween 80...tained 30 ml of distilled water for sampling of dye aerosols...spinning-disk aerosol generator (Environmental Re...ground level. Seeding of water with f2 virus and fluorescein...at the Fort Huachuca Atmospheric Sciences Laboratory...

H T Bausum; S A Schaub; K F Kenyon; M J Small

1982-01-01T23:59:59.000Z

375

Aerodynamic focusing of high-density aerosols D.E. Ruiz a,n  

E-Print Network (OSTI)

Aerodynamic focusing of high-density aerosols D.E. Ruiz a,n , L.M. Gunderson a , M.J. Hay a , E Accepted 24 May 2014 Available online 17 June 2014 Keywords: Aerodynamic lens High-density aerosol beam recover previous findings on aerodynamic focusing at low densities. At higher densities

376

Evidence for the role of organics in aerosol particle formation under atmospheric conditions  

Science Journals Connector (OSTI)

...used to simulate the solar light spectrum and start...denuder--aerosol collector (WEDD-AC) coupled...measured in the aerosol collector. The...ratio of the projected horizontal surface area to the total...run the model with a horizontal resolution of 2.8...

Axel Metzger; Bart Verheggen; Josef Dommen; Jonathan Duplissy; Andre S. H. Prevot; Ernest Weingartner; Ilona Riipinen; Markku Kulmala; Dominick V. Spracklen; Kenneth S. Carslaw; Urs Baltensperger

2010-01-01T23:59:59.000Z

377

Organic Aerosols in the Earth's J O O S T D E G O U W *  

E-Print Network (OSTI)

, and indirectly through their role as cloud-condensation nuclei. A large fraction (50%) of the submicron aerosol(primaryorganicaerosolorPOA) are distinguished from secondary organic aerosol (SOA) formed in the atmosphere from gas-phase precursors. Both POA scales of minutes: particle-into-liquid sampling combined with total organic carbon analysis for measure

Jimenez, Jose-Luis

378

Effective Henry's Law Partitioning and the Salting Constant of Glyoxal in Aerosols Containing Sulfate  

E-Print Network (OSTI)

-resolved measurements of gas-phase and particle-phase concentrations in sulfate- containing aerosols. Two complementary utilizing filter sampling of chamber aerosols followed by HPLC-MS/MS analysis and (2) positive matrix and irreversible condensed-phase reactions of these compounds yield products of lower volatility; e.g. acetal

379

Direct radiative effect of aerosols emitted by transport from road, shipping and  

E-Print Network (OSTI)

Direct radiative effect of aerosols emitted by transport from road, shipping and aviation 1234567.0 License. Atmospheric Chemistry and Physics Direct radiative effect of aerosols emitted by transport: from road, shipping and aviation Y. Balkanski1, G. Myhre2,3, M. Gauss2,*, G. R�adel4, E. J. Highwood4, and K

Wirosoetisno, Djoko

380

Cloud/Aerosol Parameterizations: Application and Improvement of General Circulation Models  

SciTech Connect

One of the biggest uncertainties associated with climate models and climate forcing is the treatment of aerosols and their effects on clouds. The effect of aerosols on clouds can be divided into two components: The first indirect effect is the forcing associated with increases in droplet concentrations; the second indirect effect is the forcing associated with changes in liquid water path, cloud morphology, and cloud lifetime. Both are highly uncertain. This project applied a cloud-resolving model to understand the response of clouds under a variety of conditions to changes in aerosols. These responses are categorized according to the large-scale meteorological conditions that lead to the response. Meteorological conditions were sampled from various fields, which, together with a global aerosol model determination of the change in aerosols from present day to pre-industrial conditions, was used to determine a first order estimate of the response of global cloud fields to changes in aerosols. The response of the clouds in the NCAR CAM3 GCM coupled to our global aerosol model were tested by examining whether the response is similar to that of the cloud resolving model and methods for improving the representation of clouds and cloud/aerosol interactions were examined.

Penner, Joyce

2012-06-30T23:59:59.000Z

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

Evolution of biomass burning aerosol properties from an agricultural fire in southern Africa  

E-Print Network (OSTI)

Evolution of biomass burning aerosol properties from an agricultural fire in southern Africa Steven Met Office C-130 within a distinct biomass burning plume during the Southern AFricAn Regional science, and P. R. Buseck, Evolution of biomass burning aerosol properties from an agricultural fire in southern

Highwood, Ellie

382

Global observations and spectral characteristics of desert dust and biomass burning aerosols  

E-Print Network (OSTI)

quantity, but a radiation difference in the UV. Its main advantages are its insensitivity to scattering in climate physics today is the effect of aerosols on the global energy budget. The amount and sign of the effect of aerosols on the incoming solar radiation are unknown and produce a large uncertainty

Graaf, Martin de

383

Infection of mice by aerosols of Klebsiella pneumoniae under hyperbaric conditions.  

Science Journals Connector (OSTI)

...equipment, and aerosol generation. Each small chamber...Mechanical Engineers Un- fired Pressure Vessel Code...or other mixed-gas atmospheres. The...gauges, electric power feed-through...of aerosol. Air (gas) in the central...of bacteriocidal power of the blood. J...

R J Heckly; M A Chatigny; R L Dimmick

1980-07-01T23:59:59.000Z

384

Cloud seeding as a technique for studying aerosol-cloud interactions in marine stratocumulus  

E-Print Network (OSTI)

Cloud seeding as a technique for studying aerosol-cloud interactions in marine stratocumulus hygroscopic aerosols were introduced into a solid marine stratocumulus cloud (200 m thick) by burning hygroscopic flares mounted on an aircraft. The cloud microphysical response in two parallel seeding plumes

Miami, University of

385

A new cloud and aerosol layer detection method based on micropulse lidar measurements  

E-Print Network (OSTI)

A new cloud and aerosol layer detection method based on micropulse lidar measurements Chuanfeng algorithm to detect aerosols and clouds based on micropulse lidar measurements. A semidiscretization is then introduced. Combined with empirical threshold values, we determine if the signal waves indicate clouds

Li, Zhanqing

386

Aging of biogenic secondary organic aerosol via gas-phase OH radical reactions  

Science Journals Connector (OSTI)

...common model that reproduces the general features of all...throughout the aerosol life cycle in the atmosphere. Aging can significantly...gas-particle interactionspart 1: General equations, parameters, and terminology . Atmos Chem...steranes) in motor oil and diesel primary organic aerosols with...

Neil M. Donahue; Kaytlin M. Henry; Thomas F. Mentel; Astrid Kiendler-Scharr; Christian Spindler; Birger Bohn; Theo Brauers; Hans P. Dorn; Hendrik Fuchs; Ralf Tillmann; Andreas Wahner; Harald Saathoff; Karl-Heinz Naumann; Ottmar Mhler; Thomas Leisner; Lars Mller; Marc-Christopher Reinnig; Thorsten Hoffmann; Kent Salo; Mattias Hallquist; Mia Frosch; Merete Bilde; Torsten Tritscher; Peter Barmet; Arnaud P. Praplan; Peter F. DeCarlo; Josef Dommen; Andre S.H. Prvt; Urs Baltensperger

2012-01-01T23:59:59.000Z

387

Sensitivity of stratospheric geoengineering with black carbon to aerosol size and altitude of injection  

E-Print Network (OSTI)

geoengineering with black carbon (BC) aerosols using a general circulation model with fixed sea surface would enhance the Arctic ozone hole. Using diesel fuel to produce the aerosols is likely prohibitively. Engineered particles, such as resonant scatterers or self-levitating particles, have been proposed

388

ENVISAT Symposium 2007 Montreux, 26 April 2007 The Relationship Between Absorbing Aerosols And Clouds  

E-Print Network (OSTI)

: aerosols over cloud #12;Solar irradiance I [W m-2 nm-1 ] Absorbed energy 25.6 Wm-2 Reflectance R I . 0E0 R aerosol / cloud layer #12; SCIAMACHY sees smoke in cloudy scene biomass burning in SW Africa, 09

Graaf, Martin de

389

BSL3 Protocols #501 Dr. Jacobs Lab Title: Aerosol Infection Procedures Date: 02/11/2005  

E-Print Network (OSTI)

. 6. Air-seal chamber door was closed, all meters were monitored to ensure proper air flow rate on the external lines and the back door O-ring seal( see Inspection Protocol) . 1. Mice to be aerosol infected containing mice were passed through air-tight tunnel to Baker Class III glove box in aerosol room. 5. Inside

390

Formation of Ozone and Growth of Aerosols in Young Smoke Plumes from Biomass Burning  

E-Print Network (OSTI)

Physics and Chemistry Abstract The combustion of biomass is a major source of atmospheric trace gasesFormation of Ozone and Growth of Aerosols in Young Smoke Plumes from Biomass Burning by Matthew and Planetary Sciences #12;Formation of Ozone and Growth of Aerosols in Young Smoke Plumes from Biomass Burning

391

Assessing the effects of anthropogenic aerosols on Pacific storm track using a multiscale global climate model  

Science Journals Connector (OSTI)

...The first MMF model was built at the Colorado State University, replacing the cloud...microphysics of clouds. As an extension to the Colorado State University MMF, an aerosol version...715 737 . 4 Rosenfeld D ( 2008 ) Flood or drought: How do aerosols affect precipitation...

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

2014-01-01T23:59:59.000Z

392

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

DOE Data Explorer (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

393

Evidence that the spectral dependence of light absorption by aerosols is  

NLE Websites -- All DOE Office Websites (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.

394

Small-Scale Spray Releases: Initial Aerosol Test Results  

SciTech Connect

One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents was assessed with most of the simulants. Orifices included round holes and rectangular slots. The round holes ranged in size from 0.2 to 4.46 mm. The slots ranged from (width length) 0.3 5 to 2.74 76.2 mm. Most slots were oriented longitudinally along the pipe, but some were oriented circumferentially. In addition, a limited number of multi-hole test pieces were tested in an attempt to assess the impact of a more complex breach. Much of the testing was conducted at pressures of 200 and 380 psi, but some tests were conducted at 100 psi. Testing the largest postulated breaches was deemed impractical because of the large size of some of the WTP equipment. This report presents the experimental results and analyses for the aerosol measurements obtained in the small-scale test stand. It includes a description of the simulants used and their properties, equipment and operations, data analysis methodologies, and test results. The results of tests investigating the role of slurry particles in plugging small breaches are reported in Mahoney et al. (2012). The results of the aerosol measurements in the large-scale test stand are reported in Schonewill et al. (2012) along with an analysis of the combined results from both test scales.

Mahoney, Lenna A.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, Garrett N.; Kurath, Dean E.; Buchmiller, William C.; Smith, Dennese M.; Blanchard, Jeremy; Song, Chen; Daniel, Richard C.; Wells, Beric E.; Tran, Diana N.; Burns, Carolyn A.

2012-11-01T23:59:59.000Z

395

Small-Scale Spray Releases: Initial Aerosol Test Results  

SciTech Connect

One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and net generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of antifoam agents was assessed with most of the simulants. Orifices included round holes and rectangular slots. For the combination of both test stands, the round holes ranged in size from 0.2 to 4.46 mm. The slots ranged from (width length) 0.3 5 to 2.74 76.2 mm. Most slots were oriented longitudinally along the pipe, but some were oriented circumferentially. In addition, a limited number of multi-hole test pieces were tested in an attempt to assess the impact of a more complex breach. Much of the testing was conducted at pressures of 200 and 380 psi, but some tests were conducted at 100 psi. Testing the largest postulated breaches was deemed impractical because of the much larger flow rates and equipment that would be required. This report presents the experimental results and analyses for the aerosol measurements obtained in the small-scale test stand. It includes a description of the simulants used and their properties, equipment and operations, data analysis methodologies, and test results. The results of tests investigating the role of slurry particles in plugging small breaches are reported in Mahoney et al. (2012). The results of the aerosol measurements in the large-scale test stand are reported in Schonewill et al. (2012) along with an analysis of the combined results from both test scales.

Mahoney, Lenna A.; Gauglitz, Phillip A.; Kimura, Marcia L.; Brown, Garrett N.; Kurath, Dean E.; Buchmiller, William C.; Smith, Dennese M.; Blanchard, Jeremy; Song, Chen; Daniel, Richard C.; Wells, Beric E.; Tran, Diana N.; Burns, Carolyn A.

2013-05-29T23:59:59.000Z

396

Large-Scale Spray Releases: Initial Aerosol Test Results  

SciTech Connect

One of the events postulated in the hazard analysis at the Waste Treatment and Immobilization Plant (WTP) and other U.S. Department of Energy (DOE) nuclear facilities is a breach in process piping that produces aerosols with droplet sizes in the respirable range. The current approach for predicting the size and concentration of aerosols produced in a spray leak involves extrapolating from correlations reported in the literature. These correlations are based on results obtained from small engineered spray nozzles using pure liquids with Newtonian fluid behavior. The narrow ranges of physical properties on which the correlations are based do not cover the wide range of slurries and viscous materials that will be processed in the WTP and across processing facilities in the DOE complex. Two key technical areas were identified where testing results were needed to improve the technical basis by reducing the uncertainty due to extrapolating existing literature results. The first technical need was to quantify the role of slurry particles in small breaches where the slurry particles may plug and result in substantially reduced, or even negligible, respirable fraction formed by high-pressure sprays. The second technical need was to determine the aerosol droplet size distribution and volume from prototypic breaches and fluids, specifically including sprays from larger breaches with slurries where data from the literature are scarce. To address these technical areas, small- and large-scale test stands were constructed and operated with simulants to determine aerosol release fractions and generation rates from a range of breach sizes and geometries. The properties of the simulants represented the range of properties expected in the WTP process streams and included water, sodium salt solutions, slurries containing boehmite or gibbsite, and a hazardous chemical simulant. The effect of anti-foam agents was assessed with most of the simulants. Orifices included round holes and rectangular slots. The round holes ranged in size from 0.2 to 4.46 mm. The slots ranged from (width length) 0.3 5 to 2.74 76.2 mm. Most slots were oriented longitudinally along the pipe, but some were oriented circumferentially. In addition, a limited number of multi-hole test pieces were tested in an attempt to assess the impact of a more complex breach. Much of the testing was conducted at pressures of 200 and 380 psi, but some tests were conducted at 100 psi. Testing the largest postulated breaches was deemed impractical because of the large size of some of the WTP equipment. The purpose of this report is to present the experimental results and analyses for the aerosol measurements obtained in the large-scale test stand. The report includes a description of the simulants used and their properties, equipment and operations, data analysis methodology, and test results. The results of tests investigating the role of slurry particles in plugging of small breaches are reported in Mahoney et al. 2012a. The results of the aerosol measurements in the small-scale test stand are reported in Mahoney et al. (2012b).

Schonewill, Philip P.; Gauglitz, Phillip A.; Bontha, Jagannadha R.; Daniel, Richard C.; Kurath, Dean E.; Adkins, Harold E.; Billing, Justin M.; Burns, Carolyn A.; Davis, James M.; Enderlin, Carl W.; Fischer, Christopher M.; Jenks, Jeromy WJ; Lukins, Craig D.; MacFarlan, Paul J.; Shutthanandan, Janani I.; Smith, Dennese M.

2012-12-01T23:59:59.000Z

397

The dependence of cloud particle size and precipitation probability on non-aerosol-loading related variables  

NLE Websites -- All DOE Office Websites (Extended Search)

Explaining and reducing the uncertainties in the first aerosol i Explaining and reducing the uncertainties in the first aerosol i Explaining and reducing the uncertainties in the first aerosol indirect effect ndirect effect Hongfei Shao and Guosheng Liu Meteorology Department, Florida State University INTRODUCTION INTRODUCTION Anthropogenic aerosols enhance cloud reflectance of solar radiation by increasing the cloud droplet number concentrations. This so-called first Aerosol Indirect Effect (AIE) has a potentially large cooling tendency on our planet. However, discrepancies of more than a factor of 2 have been reported among observations 1 as well as model simulations 2 of the AIE. Our recent study 3 shows that the discrepancies will be reduced greatly if the entrainment-mixing evaporation of cloud drops is taken into account.

398

One ARM, Two Columns and a Whole Lot of Aerosols | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

ARM, Two Columns and a Whole Lot of Aerosols ARM, Two Columns and a Whole Lot of Aerosols One ARM, Two Columns and a Whole Lot of Aerosols July 25, 2012 - 5:49pm Addthis This observatory is part of an air particles research initiative at Cape Cod National Seashore in Massachusetts, and includes dozens of sophisticated instruments that take continuous ground-based measurements of clouds, aerosols, and other atmospheric properties. | Photo courtesy of the ARM Climate Research Facility. This observatory is part of an air particles research initiative at Cape Cod National Seashore in Massachusetts, and includes dozens of sophisticated instruments that take continuous ground-based measurements of clouds, aerosols, and other atmospheric properties. | Photo courtesy of the ARM Climate Research Facility.

399

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

NLE Websites -- All DOE Office Websites (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

400

Measuring Aerosols Generated Inside Armoured Vehicles Perforated by Depleted Uranium Ammunition  

SciTech Connect

In response to questions raised after the Gulf War about the health significance of exposure to depleted uranium (DU), a study was initiated to provide an improved scientific basis for assessment of possible health effects of soldiers in vehicles struck by these munitions. As part of this experimental study, a series of DU penetrators were fired at an Abrams tank and a Bradley fighting vehicle, and the aerosols generated by vehicle perforation were collected and characterized. The aerosol sampling system designed for these tests consisted of filter cassettes, cascade impactors, a five-stage cyclone, and a moving filter. Aerosols collected were analyzed for uranium concentration and particle size distribution as a function of time. The aerosol samples were also analyzed for uranium oxide phases, particle morphology, and in vitro solubility. These data will provide input for use in future prospective and retrospective dose and health risk assessments of DU aerosols.

Parkhurst, MaryAnn

2003-01-01T23:59:59.000Z

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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.


401

The Uncertainty of Dosimetry of Radioactive and Non-Radiactive Aerosols  

NLE Websites -- All DOE Office Websites (Extended Search)

The Uncertainty of Dosimetry of Radioactive and Non-Radiactive Aerosols The Uncertainty of Dosimetry of Radioactive and Non-Radiactive Aerosols Speaker(s): Lev Ruzer Date: September 27, 2001 - 12:00pm Location: Bldg. 90 Seminar Host/Point of Contact: David Faulkner Radioactive aerosols are a substantial risk factor in radiation safety in the atomic industry, mining industry, nuclear warhead depository and nuclear waste storage, as well as the natural radioactivity in houses. Assessment of the exposure, dose and health effect is very important for workers and the general population. In the last 5-10 years the problem of dosimetry of non-radioactive aerosols has become a "hot" topic in environmental health science with emphasis on submicron and even nanometer-sized particles. Both radioactive and non-radioactive aerosols

402

Aerosol Impacts on California Winter Clouds and Precipitation during CalWater 2011: Local Pollution versus Long-Range Transported Dust  

SciTech Connect

Mineral dust aerosols often observed over California in winter and spring, associated with long-range transport from Asia and Sahara, have been linked to enhanced precipitation based on observations. Local anthropogenic pollution, on the other hand, was shown in previous observational and modeling studies to reduce precipitation. Here we incorporate recent developments in ice nucleation parameterizations to link aerosols with ice crystal formation in a spectral-bin cloud microphysical model coupled with the Weather Research and Forecasting (WRF) model, to examine the relative and combined impacts of dust and local pollution particles on cloud properties and precipitation type and intensity. Simulations are carried out for two cloud cases with contrasting meteorology and cloud dynamics that occurred on February 16 (FEB16) and March 02 (MAR02) from the CalWater 2011 field campaign. In both cases, observations show the presence of dust and biological particles in a relative pristine environment. The simulated cloud microphysical properties and precipitation show reasonable agreement with aircraft and surface measurements. Model sensitivity experiments indicate that in the pristine environment, the dust and biological aerosol layers increase the accumulated precipitation by 10-20% from the Central Valley to the Sierra Nevada Mountains for both FEB16 and MAR02 due to a ~40% increase in snow formation, validating the observational hypothesis. Model results show that local pollution increases precipitation over the windward slope of the mountains by few percent due to increased snow formation when dust is present but reduces precipitation by 5-8% if dust is removed on FEB16. The effects of local pollution on cloud microphysics and precipitation strongly depend on meteorology including the strength of the Sierra Barrier Jet, and cloud dynamics. This study further underscores the importance of the interactions between local pollution, dust, and environmental conditions for assessing aerosol effects on cold season precipitation in California.

Fan, Jiwen; Leung, Lai-Yung R.; DeMott, Paul J.; Comstock, Jennifer M.; Singh, Balwinder; Rosenfeld, Daniel; Tomlinson, Jason M.; White, Allen B.; Prather, Kimberly; Minnis, Patrick; Ayers, J. K.; Min, Qilong

2014-01-03T23:59:59.000Z

403

Capstone Depleted Uranium Aerosol Biokinetics, Concentrations, and Doses  

SciTech Connect

One of the principal goals of the Capstone Depleted Uranium (DU) Aerosol Study was to quantify and characterize DU aerosols generated inside armored vehicles by perforation with a DU penetrator. This study consequently produced a database in which the DU aerosol source terms were specified both physically and chemically for a variety of penetrator-impact geometries and conditions. These source terms were used to calculate radiation doses and uranium concentrations for various scenarios as part of the Capstone DU Human Health Risk Assessment (HHRA). This paper describes the scenario-related biokinetics of uranium, and summarizes intakes, chemical concentrations to the organs, and E(50) and HT(50) for organs and tissues based on exposure scenarios for personnel in vehicles at the time of perforation as well as for first responders. For a given exposure scenario (duration time and breathing rates), the range of DU intakes among the target vehicles and shots was not large, about a factor of 10, with the lowest being from a ventilated operational Abrams tank and the highest being for an unventilated Abrams with DU penetrator perforating DU armor. The ranges of committed effective doses were more scenario-dependent than were intakes. For example, the largest range, a factor of 20, was shown for scenario A, a 1-min exposure, whereas, the range was only a factor of two for the first-responder scenario (E). In general, the committed effective doses were found to be in the tens of mSv. The risks ascribed to these doses are discussed separately.

Guilmette, Raymond A.; Miller, Guthrie; Parkhurst, MaryAnn

2009-02-26T23:59:59.000Z

404

Radiological Risk Assessment of Capstone Depleted Uranium Aerosols  

SciTech Connect

Assessment of the health risk from exposure to aerosols of depleted uranium (DU) is an important outcome of the Capstone aerosol studies that established exposure ranges to personnel in armored combat vehicles perforated by DU munitions. Although the radiation exposure from DU is low, there is concern that DU deposited in the body may increase cancer rates. Radiation doses to various organs of the body resulting from the inhalation of DU aerosols measured in the Capstone studies were calculated using International Commission on Radiological Protection (ICRP) models. Organs and tissues with the highest calculated committed equivalent 50-yr doses were lung and extrathoracic tissues (nose and nasal passages, pharynx, larynx, mouth and thoracic lymph nodes). Doses to the bone surface and kidney were about 5 to 10% of the doses to the extrathoracic tissues. The methodologies of the ICRP International Steering Committee on Radiation Standards (ISCORS) were used for determining the whole body cancer risk. Organ-specific risks were estimated using ICRP and U.S. Environmental Protection Agency (EPA) methodologies. Risks for crewmembers and first responders were determined for selected scenarios based on the time interval of exposure and for vehicle and armor type. The lung was the organ with the highest cancer mortality risk, accounting for about 97% of the risks summed from all organs. The highest mean lifetime risk for lung cancer for the scenario with the longest exposure time interval (2 h) was 0.42%. This risk is low compared with the natural or background risk of 7.35%. These risks can be significantly reduced by using an existing ventilation system (if operable) and by reducing personnel time in the vehicle immediately after perforation.

Hahn, Fletcher; Roszell, Laurie E.; Daxon, Eric G.; Guilmette, Ray A.; Parkhurst, MaryAnn

2009-02-26T23:59:59.000Z

405

Modeling aerosol growth by aqueous chemistry in nonprecipitating stratiform cloud  

SciTech Connect

A new microphysics module based on a two-dimensional (2D) joint size distribution function representing both interstitial and cloud particles is developed and applied to studying aerosol processing in non-precipitating stratocumulus clouds. The module is implemented in a three-dimensional dynamical framework of a large-eddy simulation (LES) model and in a trajectory ensemble model (TEM). Both models are used to study the modification of sulfate aerosol by the activation - aqueous chemistry - resuspension cycle in shallow marine stratocumulus clouds. The effect of particle mixing and different size-distribution representations on modeled aerosol processing are studied in a comparison of the LES and TEM simulations with the identical microphysics treatment exposes and a comparison of TEM simulations with a 2D fixed and moving bin microphysics. Particle mixing which is represented in LES and neglected in the TEM leads to the mean relative per particle dry mass change in the TEM simulations being about 30% lower than in analogous subsample of LES domain. Particles in the final LES spectrum are mixed in from different parcels, some of which have experienced longer in-cloud residence times than the TEM parcels, all of which originated in the subcloud layer, have. The mean relative per particle dry mass change differs by 14% between TEM simulations with fixed and moving bin microphysics. Finally, the TEM model with the moving bin microphysics is used to evaluate assumptions about liquid water mass partitioning among activated cloud condensation nuclei (CCN) of different dry sizes. These assumptions are used in large-scale models to map the bulk aqueous chemistry sulfate production, which is largely proportional to the liquid water mass, to the changes in aerosol size distribution. It is shown that the commonly used assumptions that the droplet mass is independent of CCN size or that the droplet mass is proportional to the CCN size to the third power do not perform well in the considered case. The explicitly predicted water partitioning indicates that the mean mass of droplets participating in the models aqueous chemistry calculations is proportional to the dry CCN size.

Ovchinnikov, Mikhail; Easter, Richard C.

2010-07-29T23:59:59.000Z

406

DUAL ORIGIN OF AEROSOLS IN TITAN'S DETACHED HAZE LAYER  

SciTech Connect

We have analyzed scattered light profiles from the Cassini Imaging Science Subsystem, taken at the limb and at several large phase angles. We also used results from an occultation observed by Ultraviolet Imaging Spectrograph in the ultraviolet. We found that particles responsible for the scattering in the detached haze have an effective radius around 0.15 {mu}m and the aerosol size distribution follows a power law (exponent about -4.5). We discuss these results along with microphysical constraints and thermal equilibrium of the detached haze, and we conclude that only a strong interaction with atmospheric dynamics can explain such a structure.

Cours, T.; Burgalat, J.; Rannou, P. [Groupe de Spectrometrie Moleculaire et Atmospherique (GSMA), CNRS UMR-6089, Universite de Reims Champagne-Ardenne, 51687 Reims Cedex 2 (France); Rodriguez, S.; Brahic, A. [Laboratoire AIM, Universite Paris 7, CNRS UMR-7158, CEA-Saclay/DSM/IRFU/SAp, 91191 Gif/Yvette (France); West, R. A., E-mail: thibaud.cours@univ-reims.fr [Jet Propulsion Laboratory M/S 169-237, Pasadena, CA 91109 (United States)

2011-11-10T23:59:59.000Z

407

The seasonality of aerosol properties in Big Bend National Park  

E-Print Network (OSTI)

growth cycle present in the daily averaged 32 Day (December 2003) Dp (um) Day (December 2003) Dp (um) Day (January 2004) Dp (um) Day (January 2004) Dp (um) Day (June 2003) Dp (um) Day (June 2003) Dp (um) Day (April 2003) Dp (um) Day (April 2003) Dp... (um) Day (December 2003) Dp (um) Day (December 2003) Dp (um) Day (January 2004) Dp (um) Day (January 2004) Dp (um) Day (June 2003) Dp (um) Day (June 2003) Dp (um) Day (April 2003) Dp (um) Day (April 2003) Dp (um) Fig. 12. Seasonal aerosol number...

Allen, Christopher Lee

2007-04-25T23:59:59.000Z

408

Dosimeter for monitoring vapors and aerosols of organic compounds  

DOE Patents (OSTI)

A dosimeter is provided for collecting and detecting vapors and aerosols of organic compounds. The dosimeter comprises a lightweight, passive device that can be conveniently worn by a person as a badge or placed at a stationary location. The dosimeter includes a sample collector comprising a porous web treated with a chemical for inducing molecular displacement and enhancing phosphorescence. Compounds are collected onto the web by molecular diffusion. The web also serves as the sample medium for detecting the compounds by a room temperature phosphorescence technique. 7 figs.

Vo-Dinh, T.

1987-07-14T23:59:59.000Z

409

Climate response of the South Asian monsoon system to anthropogenic aerosols  

SciTech Connect

The equilibrium climate response to the total effects (direct, indirect and semi-direct effects) of aerosols arising from anthropogenic and biomass burning emissions on the South Asian summer monsoon system is studied using a coupled atmosphere-slab ocean model. Our results suggest that anthropogenic and biomass burning aerosols generally induce a reduction in mean summer monsoon precipitation over most parts of the Indian subcontinent, strongest along the western coastline of the Indian peninsula and eastern Nepal region, but modest increases also occur over the north western part of the subcontinent. While most of the noted reduction in precipitation is triggered by increased emissions of aerosols from anthropogenic activities, modest increases in the north west are mostly associated with decreases in local emissions of aerosols from forest fire and grass fire sources. Anthropogenic aerosols from outside Asia also contribute to the overall reduction in precipitation but the dominant contribution comes from aerosol sources within Asia. Local emissions play a more important role in the total rainfall response to anthropogenic aerosol sources during the early monsoon period, whereas both local as well as remote emissions of aerosols play almost equally important roles during the later part of the monsoon period. While precipitation responses are primarily driven by local aerosol forcing, regional surface temperature changes over the region are strongly influenced by anthropogenic aerosols from sources further away (non-local changes). Changes in local anthropogenic organic and black carbon emissions by as much as a factor of two (preserving their ratio) produce the same basic signatures in the model's summer monsoon temperature and precipitation responses.

Ganguly, Dilip; Rasch, Philip J.; Wang, Hailong; Yoon, Jin-Ho

2012-07-13T23:59:59.000Z

410

Deposition of biological aerosols on HVAC heat exchangers  

SciTech Connect

Many biologically active materials are transported as bioaerosols 1-10 {micro}m in diameter. These particles can deposit on cooling and heating coils and lead to serious indoor air quality problems. This paper investigates several of the mechanisms that lead to aerosol deposition on fin and tube heat exchangers. A model has been developed that incorporates the effects of several deposition mechanisms, including impaction, Brownian and turbulent diffusion, turbophoresis, thermophoresis, diffusiophoresis, and gravitational settling. The model is applied to a typical range of air velocities that are found in commercial and residential HVAC systems 1 - 6 m/s (200 - 1200 ft/min), particle diameters from 1 - 8 {micro}m, and fin spacings from 3.2 - 7.9 fins/cm (8 - 16 fins/inch or FPI). The results from the model are compared to results from an experimental apparatus that directly measures deposition on a 4.7 fins/cm (12 FPI) coil. The model agrees reasonably well with this measured data and suggests that cooling coils are an important sink for biological aerosols and consequently a potential source of indoor air quality problems.

Siegel, Jeffrey; Walker, Ian

2001-09-01T23:59:59.000Z

411

Aerosol analysis for the regional air pollution study. Final report  

SciTech Connect

The design and operation of an aerosol sampling and analysis program implemented during the 1975 to 1977 St. Louis Regional Air Pollution Study is described. A network of ten samplers were operated at selected sites in the St. Louis area and the total mass and elemental composition of the collected particulates were determined. Sampling periods of 2 to 24 hours were employed. The samplers were capable of collecting aerosol particles in two distinct size ranges corresponding to fine (< 2.4 ..mu..m diameter) and coarse (> 2.4 ..mu..m diameter) particles. This unique feature allowed the separation of the particulate samples into two distinct fractions with differing chemical origins and health effects. The analysis methods were also newly developed for use in the St. Louis RAPS study. Total particulate mass was measured by a beta-particle attenuation method in which a precision of +- 5 ..mu..m/cm/sup 2/ could be obtained in a one minute measurement time. Elemental compositions of the samples were determined using an energy dispersive x-ray fluorescence method in which detectable limits of 5 ng/cm/sup 2/ or less were routinely achieved for elements ranging in atomic number from Al to Pb. The advantages of these analytical methods over more conventional techniques arise from the ability to automate the measurements. During the course of the two year study, a total of more than 35,000 individual samples were processed and a total of 28 concentrations measured for each sample.

Jaklevic, J.M.; Gatti, R.C.; Goulding, F.S.; Loo, B.W.; Thompson, A.C.

1980-05-01T23:59:59.000Z

412

Aerosol chemical vapor deposition of metal oxide films  

DOE Patents (OSTI)

A process of preparing a film of a multicomponent metal oxide including: forming an aerosol from a solution comprised of a suitable solvent and at least two precursor compounds capable of volatilizing at temperatures lower than the decomposition temperature of said precursor compounds; passing said aerosol in combination with a suitable oxygen-containing carrier gas into a heated zone, said heated zone having a temperature sufficient to evaporate the solvent and volatilize said precursor compounds; and passing said volatilized precursor compounds against the surface of a substrate, said substrate having a sufficient temperature to decompose said volatilized precursor compounds whereby metal atoms contained within said volatilized precursor compounds are deposited as a metal oxide film upon the substrate is disclosed. In addition, a coated article comprising a multicomponent metal oxide film conforming to the surface of a substrate selected from the group consisting of silicon, magnesium oxide, yttrium-stabilized zirconium oxide, sapphire, or lanthanum gallate, said multicomponent metal oxide film characterized as having a substantially uniform thickness upon said substrate.

Ott, K.C.; Kodas, T.T.

1994-01-11T23:59:59.000Z

413

A numerical study of the effect of different aerosol types on East Asian summer clouds and precipitation  

SciTech Connect

The impact of anthropogenic aerosol on the East Asian summer monsoon (EASM) is investigated with NCAR CAM5, a state-of-the-art climate model with aerosols direct and indirect effects. Results indicate that anthropogenic aerosol tends to cause a weakened EASM with a southward shift of precipitation in East Asia mostly by its radiative effect. Anthropogenic aerosol induced surface cooling stabilizes the boundary layer, suppresses the convection and latent heat release in northern China, and reduces the tropospheric temperature over land and land-sea thermal contrast, thus leading to a weakened EASM. Meanwhile, acting as cloud condensation nuclei (CCN), anthropogenic aerosol can significantly increase the cloud droplet number concentration but decrease the cloud droplet effective radius over Indochina and Indian Peninsulas as well as over southwestern and northern China, inhibiting the precipitation in these regions. Thus, anthropogenic aerosol tends to reduce Southeast and South Asian summer monsoon precipitation by its indirect effect.

Jiang, Yiquan; Liu, Xiaohong; Yang, Xiuqun; Wang, Minghuai

2013-05-01T23:59:59.000Z

414

A Simple Apparatus for the Injection of Lithium Aerosol into the Scrape-Off Layer of Fusion Research Devices  

SciTech Connect

A simple device has been developed to deposit elemental lithium onto plasma facing components in the National Spherical Torus Experiment. Deposition is accomplished by dropping lithium powder into the plasma column. Once introduced, lithium particles quickly become entrained in scrape-off layer flow as an evaporating aerosol. Particles are delivered through a small central aperture in a computer-controlled resonating piezoelectric disk on which the powder is supported. The device has been used to deposit lithium both during discharges as well as prior to plasma breakdown. Clear improvements to plasma performance have been demonstrated. The use of this apparatus provides flexibility in the amount and timing of lithium deposition and, therefore, may benefit future fusion research devices.

D. K. Mansfield, A.L Roquemore, H. Schneider, J. Timberlake, H. Kugel, M.G. Bell and the NSTX Research Team

2010-10-11T23:59:59.000Z

415

Factors affecting the indoor concentrations of carbonaceous aerosols of outdoor origin  

SciTech Connect

A field study was conducted in an unoccupied single story residence in Clovis, California to provide data to address issues important to assess the indoor exposure to particles of outdoor origin. Measurements of black and organic carbonaceous aerosols were performed using a variety of methods, resulting in both near real-time measurements as well as integrated filter based measurements. Comparisons of the different measurement methods show that it is crucial to account for gas phase adsorption artifacts when measuring organic carbon (OC). Measured concentrations affected by the emissions of organic compounds sorbed to indoor surfaces imply a higher degree of infiltration of outdoor organic carbon aerosols into the indoor environment for our unoccupied house. Analysis of the indoor and outdoor data for black carbon (BC) aerosols show that, on average, the indoor concentration of black carbon aerosols behaves in a similar manner to sulfate aerosols. In contrast, organic carbon aerosols are subject to chemical transformations indoors that, for our unoccupied home, resulted in lower indoor OC concentrations than would be expected by physical loss mechanisms alone. These results show that gas to particle partitioning of organic compounds, as well as gas to surface interactions within the residence, are an important process governing the indoor concentration to OC aerosols of outdoor origin.

Lunden, Melissa M.; Kirchstetter, Thomas W.; Thatcher, Tracy L.; Hering, Susanne V.; Brown, Nancy J.

2007-06-25T23:59:59.000Z

416

Constraining cloud lifetime effects of aerosols using A-Train satellite observations  

SciTech Connect

Aerosol indirect effects have remained the largest uncertainty in estimates of the radiative forcing of past and future climate change. Observational constraints on cloud lifetime effects are particularly challenging since it is difficult to separate aerosol effects from meteorological influences. Here we use three global climate models, including a multi-scale aerosol-climate model PNNL-MMF, to show that the dependence of the probability of precipitation on aerosol loading, termed the precipitation frequency susceptibility (S{sub pop}), is a good measure of the liquid water path response to aerosol perturbation ({lambda}), as both Spop and {lambda} strongly depend on the magnitude of autoconversion, a model representation of precipitation formation via collisions among cloud droplets. This provides a method to use satellite observations to constrain cloud lifetime effects in global climate models. S{sub pop} in marine clouds estimated from CloudSat, MODIS and AMSR-E observations is substantially lower than that from global climate models and suggests a liquid water path increase of less than 5% from doubled cloud condensation nuclei concentrations. This implies a substantially smaller impact on shortwave cloud radiative forcing (SWCF) over ocean due to aerosol indirect effects than simulated by current global climate models (a reduction by one-third for one of the conventional aerosol-climate models). Further work is needed to quantify the uncertainties in satellite-derived estimates of S{sub pop} and to examine S{sub pop} in high-resolution models.

Wang, Minghuai; Ghan, Steven J.; Liu, Xiaohong; Ecuyer, Tristan L.; Zhang, Kai; Morrison, H.; Ovchinnikov, Mikhail; Easter, Richard C.; Marchand, Roger; Chand, Duli; Qian, Yun; Penner, Joyce E.

2012-08-15T23:59:59.000Z

417

Fast and Slow Responses of the South Asian Monsoon System to Anthropogenic Aerosols  

SciTech Connect

Using a global climate model with fully predictive aerosol life cycle, we investigate the fast and slow responses of the South Asian monsoon system to anthropogenic aerosol forcing. Our results show that the feedbacks associated with sea surface temperature (SST) change caused by aerosols play a more important role than the aerosol's direct impact on radiation, clouds and land surface (rapid adjustments) in shaping the total equilibrium climate response of the monsoon system to aerosol forcing. Inhomogeneous SST cooling caused by anthropogenic aerosols eventually reduces the meridional tropospheric temperature gradient and the easterly shear of zonal winds over the region, slowing down the local Hadley cell circulation, decreasing the northward moisture transport, and causing a reduction in precipitation over South Asia. Although total responses in precipitation are closer to the slow responses in general, the fast component dominates over land areas north of 25N. Our results also show an east-west asymmetry in the fast responses to anthropogenic aerosols causing increases in precipitation west of 80E but decreases east of it.

Ganguly, Dilip; Rasch, Philip J.; Wang, Hailong; Yoon, Jin-Ho

2012-09-25T23:59:59.000Z

418

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

SciTech Connect

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

419

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

SciTech Connect

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

420

The AeroCom Evaluation and Intercomparison of Organic Aerosol in Global Models  

This paper evaluates the current status of global modeling of the organic aerosol (OA) occurrence in the troposphere and analyzes the differences calculated between models as well as between models and observations. Thirty-one global chemistry/transport and general circulation models have participated in this intercomparison, in the framework of AeroCom phase II. The simulation of OA varies greatly between models in terms of the magnitude of primary emissions, secondary OA (SOA) formation, the number of OA species used (2 to 62), the complexity of OA parameterizations (gas-particle partitioning, chemical aging, multiphase chemistry, aerosol microphysics), and the OA physical, chemical and optical properties. The diversity of the global OA simulation results has increased since earlier AeroCom experiments, mainly due to the increasing complexity of the SOA parameterization in models, and the implementation of new, highly uncertain, OA sources. Diversity of over an order of magnitude exists in the modeled vertical distribution of OA that deserves a dedicated future study. Furthermore, although the OA/OC ratio depends on OA sources and atmospheric processing and is important for model evaluation against OA and OC observations, it is resolved only by few global models. The median global primary OA source strength is 56 Tg a 1 (range 34 - 144 Tg a-1) and the median secondary OA source strength (natural and anthropogenic) is 19 Tg a-1 (range 13-121 Tg a-1). Among the models that take into account the semi-volatile SOA nature, the median source is calculated to be 51 Tg a-1 (range 16-121 Tg a-1), much larger than the median value of the models that calculate SOA in a more simplistic way (19 Tg a-1; range 13-20 Tg a-1, with one model at 37 Tg a-1). The median atmospheric burden of OA is 1.4 Tg (24 models in the range of 0.6-2.0 Tg and 4 between 2.4-3.8 Tg) with a median OA lifetime of 5.4 days (range 3.8-9.6 days). In models that reported both OA and sulfate burdens, the median value of the OA/sulfate burden ratio of is calculated to be 0.77; 13 models calculate a ratio lower than 1, and 9 models higher than 1. For 26 models that reported OA deposition fluxes, the median wet removal is 70 Tg a-1 (range 28-209 Tg a-1), which is on average 85% of the total OA deposition.

Tsigaridis, Kostas; Daskalakis, N.; Kanakidou, M.; Adams, P. J.; Artaxo, Paulo; Bahadur, R.; Balkanski, Y.; Bauer, S.; Bellouin, N.; Benedetti, Angela; Bergman, T.; Berntsen, T.; Beukes, J. P.; Bian, Huisheng; Carslaw, K. S.; Chin, M.; Curci, Gabriele; Diehl, Thomas; Easter, Richard C.; Ghan, Steven J.; Gong, S.; Hodzic, Alma; Hoyle, Christopher R.; Iversen, T.; Jathar, S.; Jimenez, J. L.; Kaiser, J. W.; Kirkevag, A.; Koch, Dorothy; Kokkola, H.; Lee, Y. H.; Lin, G.; Liu, Xiaohong; Luo, Gan; Ma, Xiaoyan; Mann, G. W.; Mihalopoulos, Nikos; Morcrette, J. -J.; Muller, J. F.; Myhre, G.; Myriokefalitakis, S.; Ng, Nga L.; O'Donell, D.; Penner, J. E.; Pozzoli, L.; Pringle, K. J.; Russell, Lynn; Schulz, M.; Sciare, J.; Seland, O.; Shindell, Drew; Sillman, S.; Skeie, R. B.; Spracklen, D. V.; Stavrakou, T.; Steenrod, Stephen D.; Takemura, T.; Tiitta, P.; Tilmes, S.; Tost, H.; van Noije, T.; van Zyl, P. G.; von Salzen, Knut; Yu, Fangqun; Wang, Zaizi; Wang, Zhilli; Zaveri, Rahul A.; Zhang, Hua; Zhang, Kai; Zhang, Qi; Zhang, Xiaoye

2014-10-15T23:59:59.000Z

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

Overview of the Capstone Depleted Uranium Study of Aerosols from Impact with Armored Vehicles: Test Setup and Aerosol Generation, Characterization, and Application in Assessing Dose and Risk  

SciTech Connect

The Capstone Depleted Uranium (DU) Aerosol Characterization and Risk Assessment Study was conducted to generate data about DU aerosols generated during the perforation of armored combat vehicles with large-caliber DU penetrators, and to apply the data in assessments of human health risks to personnel exposed to these aerosols, primarily through inhalation, during the 1991 Gulf War or in future military operations. The Capstone study consisted of two components: 1) generating, sampling and characterizing DU aerosols by firing at and perforating combat vehicles and 2) applying the source-term quantities and characteristics of the aerosols to the evaluation of doses and risks. This paper reviews the background of the study including the bases for the study, previous reviews of DU particles and health assessments from DU used by the U.S. military, the objectives of the study components, the participants and oversight teams, and the types of exposures it was intended to evaluate. It then discusses exposure scenarios used in the dose and risk assessment and provides an overview of how the field tests and dose and risk assessments were conducted.

Parkhurst, MaryAnn; Guilmette, Raymond A.

2009-03-01T23:59:59.000Z

422

Automated Sealing of Home Enclosures with Aerosol Particles  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

October 14, 2011 October 14, 2011 Automated Sealing of Home Enclosures with Aerosol Particles Welcome to the Webinar! We will start at 11:00 AM Eastern Time Be sure that you are also dialed into the telephone conference call: Dial-in number: 888-989-7679; Pass code: 3599368 Download the presentation at: www.buildingamerica.gov/meetings.html Building Technologies Program eere.energy.gov Building America: Introduction October 14, 2011 Chuck Booten Chuck.booten@nrel.gov Building Technologies Program Building Technologies Program eere.energy.gov * Reduce energy use in new and existing residential buildings * Promote building science and systems engineering / integration approach * "Do no harm": Ensure safety, health and durability are maintained or improved

423

Source Attribution of Light Absorbing Aerosol in Arctic Snow  

NLE Websites -- All DOE Office Websites (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

424

Photometric Variations as Small Perturbations in Aerosol Content  

NLE Websites -- All DOE Office Websites (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.

425

Sensitive glow discharge ion source for aerosol and gas analysis  

DOE Patents (OSTI)

A high sensitivity glow discharge ion source system for analyzing particles includes an aerodynamic lens having a plurality of constrictions for receiving an aerosol including at least one analyte particle in a carrier gas and focusing the analyte particles into a collimated particle beam. A separator separates the carrier gas from the analyte particle beam, wherein the analyte particle beam or vapors derived from the analyte particle beam are selectively transmitted out of from the separator. A glow discharge ionization source includes a discharge chamber having an entrance orifice for receiving the analyte particle beam or analyte vapors, and a target electrode and discharge electrode therein. An electric field applied between the target electrode and discharge electrode generates an analyte ion stream from the analyte vapors, which is directed out of the discharge chamber through an exit orifice, such as to a mass spectrometer. High analyte sensitivity is obtained by pumping the discharge chamber exclusively through the exit orifice and the entrance orifice.

Reilly, Peter T. A. (Knoxville, TN)

2007-08-14T23:59:59.000Z

426

A numerical model of aerosol scavenging: Part 1, Microphysics parameterization  

SciTech Connect

We have developed a three-dimensional numerical model (OCTET) to simulate the dynamics and microphysics of clouds and the transport, diffusion and precipitation scavenging of aerosol particles. In this paper we describe the cloud microphysics and scavenging parameterizations. The representation of cloud microphysics is a bulk- water parameterization which includes water vapor and five types of hydrometeors (cloud droplets, rain drops, ice crystals, snow, and graupel). A parallel parameterization represents the scavenging interactions between pollutant particles and hydrometeors including collection of particles because of condensation nucleation, Brownian and phoretic attachment, and inertial capture, resuspension because of evaporation and sublimation; and transfer interactions where particles collected by one type of hydrometeor are transferred to another type of freezing, melting, accretion, riming and autoconversion.

Molenkamp, C.R.; Bradley, M.M.

1991-09-01T23:59:59.000Z

427

Options for controlling condensation aerosols to meet opacity standards  

SciTech Connect

The article gives results of an analysis of the condensing aerosol problem and an evaluation of possible control approaches to reduce the downwind detached plume opacity. The opacity of such plumes may be reduced by reducing the concentration of condensible vapors, the in-stack concentration of fine particles, or both. Results of the analysis indicate that, for low concentrations of condensible vapors, the detached-plume opacity may be adequately controlled by reducing the in-stack fine-particulate concentration alone. For high concentrations of condensible vapors, however, reduction of in-stack fine particulate concentration alone may not be effective: reduction of vapor concentration may be necessary along with particulate removal for adequate reduction of plume opacity. Different combinations of levels of reduction of vapor concentration and particulate-phase concentration are possible to achieve a desired result; and thus may be optimized to obtain a cost-effective combination.

Damle, A.S.; Ensor, D.S.; Sparks, L.E.

1987-01-01T23:59:59.000Z

428

Indirect radiative forcing by ion-mediated nucleation of aerosol  

SciTech Connect

A clear understanding of particle formation mechanisms is critical for assessing aerosol indirect radiative forcing and associated climate feedback processes. Recent studies reveal the importance of ion-mediated nucleation (IMN) in generating new particles and cloud condensation nuclei (CCN) in the atmosphere. Here we implement for the first time a physically based treatment of IMN into the Community Atmosphere Model version 5. Our simulations show that, compared to globally averaged results based on binary homogeneous nucleation (BHN), the presence of ionization (i.e., IMN) halves H2SO4 column burden, but increases the column integrated nucleation rate by around one order of magnitude, total particle number burden by a factor of ~ 3, CCN burden by ~ 10% (at 0.2% supersaturation) to 65% (at 1.0% supersaturation), and cloud droplet number burden by ~ 18%. Compared to BHN, IMN increases cloud liquid water path by 7.5%, decreases precipitation by 1.1%, and increases total cloud cover by 1.9%. This leads to an increase of total shortwave cloud radiative forcing by 3.67 W/m2 (more negative) and longwave cloud forcing by 1.78 W/m2 (more positive), resulting in a -1.9 W/m2 net change in cloud radiative forcing associated with IMN. The significant impacts of ionization on global aerosol formation, CCN abundance, and cloud radiative forcing may provide an important physical mechanism linking the global energy balance to various processes affecting atmospheric ionization, which should be properly represented in climate models.

Yu, Fangqun; Luo, Gan; Liu, Xiaohong; Easter, Richard C.; Ma, Xiaoyan; Ghan, Steven J.

2012-12-03T23:59:59.000Z

429

Aerodyne Develops an Aircraft-Deployable Precision Aerosol Analyzer | U.S.  

Office of Science (SC) Website

Aerodyne Develops an Aircraft-Deployable Precision Aerosol Aerodyne Develops an Aircraft-Deployable Precision Aerosol Analyzer Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) SBIR/STTR Home About Funding Opportunity Announcements (FOAs) Applicant and Awardee Resources Commercialization Assistance Other Resources Awards SBIR/STTR Highlights Reporting Fraud Contact Information Small Business Innovation Research and Small Business Technology Transfer U.S. Department of Energy SC-29/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-5707 F: (301) 903-5488 E: sbir-sttr@science.doe.gov More Information » January 2013 Aerodyne Develops an Aircraft-Deployable Precision Aerosol Analyzer Aerodyne Research Inc. develops an aerosol mass spectrometer (AMS) that fills a critical need for size-resolved, quantitative chemical composition

430

Surface-Based Remote Sensing of the Aerosol Indirect Effect at Southern Great Plains  

NLE Websites -- All DOE Office Websites (Extended Search)

Surface-Based Remote Sensing of the Surface-Based Remote Sensing of the Aerosol Indirect Effect at Southern Great Plains G. Feingold and W. L. Eberhard National Oceanic and Atmospheric Administration Environmental Technology Laboratory Boulder, Colorado D. E. Vernon and M. Previdi Rutgers University New Brunswick, New Jersey Abstract We have demonstrated first measurements of the aerosol indirect effect using ground-based remote sensors at the Southern Great Plains (SGP) site. The response of non-precipitating, ice-free clouds to changes in aerosol loading is quantified in terms of a relative change in cloud-drop effective radius (r e ) for a relative change in aerosol extinction under conditions of equivalent cloud liquid water path (LWP). This is done in a single column of air at a temporal resolution of 20 s (spatial resolution of ~100 m).

431

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

NLE Websites -- All DOE Office Websites (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

432

Factors affecting the indoor concentrations of carbonaceous aerosols of outdoor origin  

NLE Websites -- All DOE Office Websites (Extended Search)

Factors affecting the indoor concentrations of carbonaceous aerosols of Factors affecting the indoor concentrations of carbonaceous aerosols of outdoor origin Melissa M. Lunden 1 ∗ , Thomas W. Kirchstetter 1 , Tracy L. Thatcher 2 , Susanne V. Hering 3 , and Nancy J. Brown 1 1 Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720, USA 2 Department of Civil and Environmental Engineering, California Polytechnic State University, San Luis Obispo, CA 93407, USA 2 Aerosol Dynamics Inc., 2329 4th Street, Berkeley, CA 94710, USA Abstract A field study was conducted in an unoccupied single story residence in Clovis, California to provide data to address issues important to assess the indoor exposure to particles of outdoor origin. Measurements of black and organic carbonaceous aerosols were performed using a

433

E-Print Network 3.0 - aerosol particle formation Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

of aerosol over many orders-of-magnitude of particle size range, from subcritical clusters on the molecular... of Energy under Contract No. DE-AC02-98CH10886....

434

The Airborne CloudAerosol Transport System: Overview and Description of the Instrument and Retrieval Algorithms  

Science Journals Connector (OSTI)

The Airborne CloudAerosol Transport System (ACATS) is a Doppler wind lidar system that has recently been developed for atmospheric science capabilities at the NASA Goddard Space Flight Center (GSFC). ACATS is also a high-spectral-resolution lidar ...

John E. Yorks; Matthew J. McGill; V. Stanley Scott; Shane W. Wake; Andrew Kupchock; Dennis L. Hlavka; William D. Hart; Patrick A. Selmer

2014-11-01T23:59:59.000Z

435

Computational Fluid Dynamics (CFD) simulations of dilute fluid-particle flows in aerosol concentrators  

E-Print Network (OSTI)

's turbulent dispersion model. A detailed literature survey revealed the inherent technical deficiencies in the model, even for particle dispersion. Based on the results of this study, it was determined that while the code can be used for simulating aerosol...

Hari, Sridhar

2005-02-17T23:59:59.000Z

436

Aerosol number concentrations and visibility during dense fog over a subtropical urban site  

Science Journals Connector (OSTI)

There is now enough evidence of greater frequencies and extent of fog formation in urban areas. These could easily be linked to rapid increase in aerosol number concentration (ANC) peculiar to polluted urban environments. It is therefore pertinent to ...

Manju Mohan, Swagata Payra

2014-01-01T23:59:59.000Z

437

E-Print Network 3.0 - aerosol monitor development Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

monitor development Page: << < 1 2 3 4 5 > >> 1 The Way Forward2 Authors: David Rind, NASA GISS; Ralph A. Kahn, NASA GSFC; Mian Chin, NASA3 Summary: the future satellite aerosol...

438

E-Print Network 3.0 - aerosol polarimetry sensor Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

sensor Page: << < 1 2 3 4 5 > >> 1 National Aeronautics and Space Administration. www.nasa.gov. Summary: energy that strikes the top of the atmosphere. Meanwhile, Glory's Aerosol...

439

Urban Aerosol Impacts on Downwind Convective Storms SUSAN C. VAN DEN HEEVER AND WILLIAM R. COTTON  

E-Print Network (OSTI)

Urban Aerosol Impacts on Downwind Convective Storms SUSAN C. VAN DEN HEEVER AND WILLIAM R. COTTON. 2004; Givati and Rosenfeld 2004; Molders and Olson 2004; Jirak and Cotton 2006); 2) increased surface

Collett Jr., Jeffrey L.

440

Resuspension of Powders and Deposition of Aerosol Particles in the Upper Human Airways  

Science Journals Connector (OSTI)

Aerosols for therapy are produced by ultrasonic nebulizers, pneumatic nebulizers, pressurized metered dose inhalers (pMDI) and dry powder inhalers (DPI). Each method of generation has its own characteristic wi...

Prof. Leon Grado?; Dr Tomasz R. Sosnowski

2003-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

Aerosol Resuspension Model for MELCOR for Fusion and Very High Temperature Reactor Applications  

SciTech Connect

Dust is generated in fusion reactors from plasma erosion of plasma facing components within the reactors vacuum vessel (VV) during reactor operation. This dust collects in cooler regions on interior surfaces of the VV. Because this dust can be radioactive, toxic, and/or chemically reactive, it poses a safety concern, especially if mobilized by the process of resuspension during an accident and then transported as an aerosol though out the reactor confinement building, and possibly released to the environment. A computer code used at the Idaho National Laboratory (INL) to model aerosol transport for safety consequence analysis is the MELCOR code. A primary reason for selecting MELCOR for this application is its aerosol transport capabilities. The INL Fusion Safety Program (FSP) organization has made fusion specific modifications to MELCOR. Recent modifications include the implementation of aerosol resuspension models in MELCOR 1.8.5 for Fusion. This paper presents the resuspension models adopted and the initial benchmarking of these models.

B.J. Merrill

2011-01-01T23:59:59.000Z

442

E-Print Network 3.0 - aerosols teresa application Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

results for: aerosols teresa application Page: << < 1 2 3 4 5 > >> 1 UC San Diego Foundation Teresa T. Young, 74 Summary: UC San Diego Foundation Trustee Teresa T. Young, 74...

443

Chemistry of carbonaceous aerosols : studies of atmospheric processing and OH-initiated oxidation  

E-Print Network (OSTI)

Carbonaceous aerosols are among the most prevalent yet least understood constituents of the atmosphere, particularly in urban environments. We have performed analyses of field samples and laboratory studies to probe the ...

Johnson, Kirsten S. (Kirsten Sue)

2008-01-01T23:59:59.000Z

444

Aerosol-nutrient-induced picoplankton growth in Lake Tahoe Katherine R. M. Mackey,1,2  

E-Print Network (OSTI)

Aerosol-nutrient-induced picoplankton growth in Lake Tahoe Katherine R. M. Mackey,1,2 Deborah been observed in Lake Tahoe in the last several decades and, in particular, following the Wheeler

Paytan, Adina

445

Quantifying the Hygroscopic Growth of Marine Boundary Layer Aerosols by Satellite-base and Buoy Observations  

Science Journals Connector (OSTI)

In this study, collocated satellite and buoy observations as well as satellite observations over an extended region during 2006-2010 were used to quantify the humidity effects on marine boundary layer (MBL) aerosols. Although the near-surface ...

Tao Luo; Renmin Yuan; Zhien Wang; Damao Zhang

446

The Campaign on atmospheric Aerosol REsearch network of China: CARE-China  

Science Journals Connector (OSTI)

Based on a network of field stations belonging to the Chinese Academy of Sciences (CAS), the Campaign on atmospheric Aerosol REsearch network of China (CARE-China) was recently established as the country's first monitoring network for the study ...

Yuesi Wang; Jinyuan Xin; Yuepeng Pan; Dongsheng Ji; Zirui Liu; Tianxue Wen; Yinghong Wang; Xingru Li; Yang Sun; Jie Sun; Pucai Wang; Gehui Wang; Xinming Wang; Zhiyuan Cong; Tao Song; Bo Hu; Lili Wang; Guiqian Tang; Wenkang Gao; Yuhong Guo; Hongyan Miao; Shili Tian; Lu Wang

447

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

448

A two-dimensional volatility basis set Part 2: Diagnostics of organic-aerosol evolution  

E-Print Network (OSTI)

We discuss the use of a two-dimensional volatility-oxidation space (2-D-VBS) to describe organic-aerosol chemical evolution. The space is built around two coordinates, volatility and the degree of oxidation, both of which ...

Donahue, N. M.

449

New Chemical Aerosol Characterization Methods- Examples Using Agricultural and Urban Airborne Particulate Matter  

E-Print Network (OSTI)

quality (Sweeten et al., 1998). However, accurate data for a number of regulated pollutants is lacking, and more measurements of agricultural aerosols are needed. A better understanding of the chemical composition of PM is also necessary for a complete...

Zhou, Lijun

2010-10-12T23:59:59.000Z

450

A Study of Aerosol Impacts on Clouds and Precipitation Development in a Large Winter Cyclone  

Science Journals Connector (OSTI)

Aerosols influence cloud and precipitation development in complex ways due to myriad feedbacks at a variety of scales from individual clouds through entire storm systems. This paper describes the implementation, testing, and results of a newly ...

Gregory Thompson; Trude Eidhammer

2014-10-01T23:59:59.000Z

451

Atmospheric aerosols and possibilities of their analysis for elemental content at the IBR-2 reactor  

Science Journals Connector (OSTI)

Possibilities of neutron activation analysis for studying the elemental content of atmospheric aerosols at the IBR-2 reactor are discussed on the bases of the ... contents on the sensitivity of NAA, the reliability

V. F. Peresedov

1997-10-01T23:59:59.000Z

452

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.

453

Studying Clouds and Aerosols with Lidar Depolarization Ratio and Backscatter Relationships  

E-Print Network (OSTI)

comparison of mineral dust aerosol retrievals from two instruments, MODIS and CALIPSO lidar. And, we implement and evaluate a new mineral dust detection algorithm based on the analysis of thin dust radiative signature. In comparison, three commonly used...

Cho, Hyoun-Myoung

2012-02-14T23:59:59.000Z

454

E-Print Network 3.0 - aerosol content monitoring Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

carbonaceous aerosols according to their organic carbon, elemental carbon and carbonate content... of Energy under Contract No. DE-AC02-98CH10886. BNL-61626 Visibility-reducing...

455

Conclusions of the Capstone Depleted Uranium Aerosol Characterization and Risk Assessment Study  

SciTech Connect

The rationale for the Capstone Depleted Uranium (DU) Aerosol Characterization and Risk Assessment Program and its results and applications have been examined in the previous 13 articles of this special issue. This paper summarizes the results and discusses its successes and lessons learned. The robust data from the Capstone DU Aerosol Study have provided a sound basis for assessing the inhalation exposure to DU aerosols and the dose and risk to personnel in combat vehicles at the time of perforation and to those entering immediately after perforation. The Human Health Risk Assessment provided a technically sound process for evaluating chemical and radiological doses and risks from DU aerosol exposure using well-accepted biokinetic and dosimetric models innovatively applied. An independent review of the study process and results is summarized, and recommendations for possible avenues of future study by the authors and by other major reviews of DU health hazards are provided.

Parkhurst, MaryAnn; Guilmette, Raymond A.

2009-02-26T23:59:59.000Z

456

Teratogenicity of depleted uranium aerosols: A review from an epidemiological perspective  

Science Journals Connector (OSTI)

Depleted uranium is being used increasingly often as a component of munitions in military conflicts. Military personnel, civilians and the DU munitions producers are being exposed to the DU aerosols that are g...

Rita Hindin; Doug Brugge; Bindu Panikkar

2005-08-01T23:59:59.000Z

457

Methods Used to Calculate Doses Resulting from Inhalation of Capstone Depleted Uranium Aerosols  

SciTech Connect

The methods used to calculate radiological and toxicological doses to hypothetical persons inside either a United States Army Abrams tank or Bradley Fighting Vehicle that has been perforated by depleted uranium munitions is described. Data from time- and particle-size-resolved measurements of depleted uranium aerosol as well as particle-size resolved measurements of aerosol solubility in lung fluids for aerosol produced in the breathing zones of the hypothetical occupants were used. The aerosol was approximated as a mixture of nine monodisperse (single particle size) components corresponding to particle size increments measured by the eight stages plus backup filter of the cascade impactors used. A Markov Chain Monte Carlo Bayesian analysis technique was employed, which straightforwardly calculates the uncertainties in doses. Extensive quality control checking of the various computer codes used is described.

Miller, Guthrie; Cheng, Yung-Sung; Traub, Richard J.; Little, Thomas T.; Guilmette, Ray A.

2009-02-26T23:59:59.000Z

458

Transport of Atmospheric Aerosol by Gap Winds in the Columbia River Gorge  

Science Journals Connector (OSTI)

Typical diurnal wind patterns and their relationship to transport of atmospheric aerosol in the Columbia River gorge of Oregon and Washington are addressed in this paper. The measurement program included measurements of light scattering by ...

Mark C. Green; Jin Xu; Narendra Adhikari

2008-01-01T23:59:59.000Z

459

FY 2011 Third Quarter Report Estimate of Historical Aerosol Direct and Indirect Effects  

SciTech Connect

The global and annual mean aerosol direct and indirect effects estimated from Community Earth System Model (CESM) simulations are -0.06 W m-2 and -1.39 W m-2, respectively.

Koch, D

2011-06-22T23:59:59.000Z

460

Determination of particulate lead using aerosol mass spectrometry: MILAGRO/MCMA-2006 observations  

E-Print Network (OSTI)

We report the first measurements of particulate lead (Pb) from Aerodyne Aerosol Mass Spectrometers, which were deployed in and around Mexico City during the Megacity Initiative: Local and Global Research Observations ...

Salcedo, D.

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

Chapter 3: Evaluating the impacts of carbonaceous aerosols on clouds and climate  

E-Print Network (OSTI)

aerosols from fossil fuel, bio fuel and biomass sources) andof natural gas to replace bio fuels, etc. ) than that forTotal (fossil- and bio fuel, biomass) Direct forcing (W m )

Menon, Surabi

2008-01-01T23:59:59.000Z

462

Association of Non-Marine Sulfate Aerosol with Sea Breeze Circulation in Tampa Bay  

Science Journals Connector (OSTI)

Peak concentrations of aerosol sulfur in Tampa, Florida may be the result of either regional-scale transformation and transport processes or local-scale transport from nearby air pollution sources. The existence of the latter has been ...

George S. Young; John W. Winchester

1980-04-01T23:59:59.000Z

463

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

NLE Websites -- All DOE Office Websites (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...

464

A Satellite-Based Parameter to Monitor the Aerosol Impact on Convective Clouds  

Science Journals Connector (OSTI)

A method to monitor the aerosol impact on convective clouds using satellite data is presented. The impacts of forest fires and highly polluting megacities on cloud precipitation formation processes are quantified by the vertical extent above ...

Itamar M. Lensky; Ron Drori

2007-05-01T23:59:59.000Z

465

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

E-Print Network (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 ...

Cziczo, Daniel James

466

Culture-Independent Analysis of Aerosol Microbiology in a Metropolitan Subway System  

Science Journals Connector (OSTI)

...Cellular, and Developmental Biology, University of Colorado, Boulder, Colorado, USA a Department of Pediatrics, University of...Ambient bioaerosol indices for indoor air quality assessments of flood reclamation.J. Aerosol Sci. 36 :763-783. 31. Kuczynski...

Charles E. Robertson; Laura K. Baumgartner; J. Kirk Harris; Kristen L. Peterson; Mark J. Stevens; Daniel N. Frank; Norman R. Pace

2013-03-29T23:59:59.000Z

467

Emission and Chemistry of Organic Carbon in the Gas and Aerosol...  

NLE Websites -- All DOE Office Websites (Extended Search)

and Chemistry of Organic Carbon in the Gas and Aerosol Phase at a Sub-Urban Site Near Mexico City in March 2006 During Emission and Chemistry of Organic Carbon in the Gas and...

468

E-Print Network 3.0 - aerosols dans le Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

AN ADVECTIVE HYPOTHESIS FOR THE FORMATION OF THE STRATOSPHERIC AEROSOL LAYER M. KRITZ Abstract... . -- In earlier work we concluded that the large ( 0.3 u rad) particles of...

469

E-Print Network 3.0 - aerosol particle concentration Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

and absorb shortwave (solar) radiation and... of the U.S. Department of Energy under Contract No. DE-AC02-98CH10886. AEROSOLS AND CLIMATE CHANGE... -5000 October 2004 Presented at...

470

E-Print Network 3.0 - ambient aerosol concentrations Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

investigators was performed under the auspices of the U.S. Department of Energy under Contract No. DE-AC02-98CH10886. Summary: organic aerosol concentrations and individual organic...

471

E-Print Network 3.0 - aerosol particles originating Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

the U.S. Department of Energy under Contract No. DE-AC02-98CH10886. Summary: incoming solar radiation, either directly or indirectly as cloud particles, aerosols exert a cooling...

472

E-Print Network 3.0 - affect atmospheric aerosols Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

and absorb shortwave (solar) radiation and... of the U.S. Department of Energy under Contract No. DE-AC02-98CH10886. AEROSOLS AND CLIMATE CHANGE... : A TUTORIAL S. E. Schwartz...

473

E-Print Network 3.0 - aerosol flow reactor Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

Materials Science 5 7, 40354064, 2007 Light induced Summary: than in the aerosol flow tube and its travel time through the reactor increases with pH. It appears... different...

474

DETERMINATION OF LOW-Z ELEMENTS IN ATMOSPHERIC AEROSOLS BY CHARGED-PARTICLE-INDUCED NUCLEAR REACTIONS  

E-Print Network (OSTI)

the nuclear reaction N14 (p,a)c 11 with low-energy protonsLOW-Z ELEMENTS IN ATMOSPHERIC AEROSOLS BY CHARGED-PARTICLE-INDUCED NUCLEAR REACTIONS Mark Steven Clemenson Energy

Clemenson, Mark Steven

2013-01-01T23:59:59.000Z

475

Contrasting the direct radiative effect and direct radiative forcing of aerosols  

E-Print Network (OSTI)

The direct radiative effect (DRE) of aerosols, which is the instantaneous radiative impact of all atmospheric particles on the Earth's energy balance, is sometimes confused with the direct radiative forcing (DRF), which ...

Heald, Colette L.

476

Climatic effects of 19502050 changes in US anthropogenic aerosols Part 2: Climate response  

E-Print Network (OSTI)

We investigate the climate response to changing US anthropogenic aerosol sources over the 19502050 period by using the NASA GISS general circulation model (GCM) and comparing to observed US temperature trends. Time-dependent ...

Leibensperger, Eric Michael

477

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

SciTech Connect

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

478

Global distribution and climate forcing of marine organic aerosol: 1. Model improvements and evaluation  

SciTech Connect

Marine organic aerosol emissions have been implemented and evaluated within the National Center of Atmospheric Research (NCAR)'s Community Atmosphere Model (CAM5) with the Pacific Northwest National Laboratory's 7-mode Modal Aerosol Module (MAM-7). Emissions of marine primary organic aerosols (POA), phytoplanktonproduced isoprene- and monoterpenes-derived secondary organic aerosols (SOA) and methane sulfonate (MS{sup -}) are shown to affect surface concentrations of organic aerosols in remote marine regions. Global emissions of submicron marine POA is estimated to be 7.9 and 9.4 Tg yr{sup -1}, for the Gantt et al. (2011) and Vignati et al. (2010) emission parameterizations, respectively. Marine sources of SOA and particulate MS{sup -} (containing both sulfur and carbon atoms) contribute an additional 0.2 and 5.1 Tg yr{sup -1}, respectively. Widespread areas over productive waters of the Northern Atlantic, Northern Pacific, and the Southern Ocean show marine-source submicron organic aerosol surface concentrations of 100 ngm{sup -3}, with values up to 400 ngm{sup -3} over biologically productive areas. Comparison of long-term surface observations of water insoluble organic matter (WIOM) with POA concentrations from the two emission parameterizations shows that despite revealed discrepancies (often more than a factor of 2), both Gantt et al. (2011) and Vignati et al. (2010) formulations are able to capture the magnitude of marine organic aerosol concentrations, with the Gantt et al. (2011) parameterization attaining better seasonality. Model simulations show that the mixing state of the marine POA can impact the surface number concentration of cloud condensation nuclei (CCN). The largest increases (up to 20 %) in CCN (at a supersaturation (S) of 0.2 %) number concentration are obtained over biologically productive ocean waters when marine organic aerosol is assumed to be externally mixed with sea-salt. Assuming marine organics are internally-mixed with sea-salt provides diverse results with increases and decreases in the concentration of CCN over different parts of the ocean. The sign of the CCN change due to the addition of marine organics to seasalt aerosol is determined by the relative significance of the increase in mean modal diameter due to addition of mass, and the decrease in particle hygroscopicity due to compositional changes in marine aerosol. Based on emerging evidence for increased CCN concentration over biologically active surface ocean areas/periods, our study suggests that treatment of sea spray in global climate models (GCMs) as an internal mixture of marine organic aerosols and sea-salt will likely lead to an underestimation in CCN number concentration.

Meskhidze, N.; Xu, J.; Gantt, Brett; Zhang, Yang; Nenes, Athanasios; Ghan, Steven J.; Liu, Xiaohong; Easter, Richard C.; Zaveri, Rahul A.

2011-11-23T23:59:59.000Z

479

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

480

Atmospheric Measurements of Submicron Aerosols at the California-Mexico Border and in Houston, Texas  

E-Print Network (OSTI)

Pacific Northwest National Laboratory POAs Primary Organic Aerosols SEMARNAT Secretaria del Medio Ambiente Recursos Naturales SHARP Study of Houston Atmospheric Radical Precursors SSA Single Scattering Albedo SOAs Secondary Organic Aerosols... quality and climate. Historically, the region has exceeded both the US EPA National Ambient Air Quality (NAAQS) and Mexico?s Secretaria del Medio Ambiente Recursos Naturales (SEMARNAT) air standards, stimulating a united interest. When comparing...

Levy, Misti E

2013-04-29T23:59:59.000Z

Note: This page contains sample records for the topic "max-mex-megacity aerosol experiment" 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

Measurements of Aerosol Charge and Size Distribution for Graphite, Gold, Palladium, and Silver Nanoparticles  

SciTech Connect

The role of charge on aerosol evolution and hence the nuclear source term has been an issue of interest, and there is a need for both experimental techniques and modeling for quantifying this role. Our focus here is on further exploration of a tandem differential mobility analyzer (TDMA) technique to simultaneously measure both the size and charge (positive, negative and neutral) dependent aerosol distributions. We have generated graphite, gold, silver, and palladium nanoparticles (aerosol) using a spark generator. We measure the electrical mobility-size distributions for these aerosols using a TDMA, and from these data we deduce the full charge-size distributions. We observe asymmetry in the particle size distributions for negative and positive charges. This asymmetry could have a bearing on the dynamics of charged aerosols, indicating that the assumption of symmetry for size distributions of negatively and positively charged particles in source term simulations may not be always appropriate. Also, the experimental technique should find applications in measurements of aerosol rate processes that are affected by both particle charge and size (e.g. coagulation, deposition, resuspension), and hence in modeling and simulation of the nuclear source term.

Simones, Matthew P.; Gutti, Veera R.; Meyer, Ryan M.; Loyalka, Sudarshan K.

2011-11-01T23:59:59.000Z

482

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

483

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

NLE Websites -- All DOE Office Websites (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

484

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

SciTech Connect

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