Science.gov

Sample records for atmospheric pollutant modeling

  1. Atmospheric pollution

    SciTech Connect

    Pickett, E.E.

    1987-01-01

    Atmospheric pollution (AP), its causes, and measures to prevent or reduce it are examined in reviews and reports presented at a workshop held in Damascus, Syria in August 1985. Topics discussed include AP and planning studies, emission sources, pollutant formation and transformation, AP effects on man and vegetation, AP control, atmospheric dispersion mechanisms and modeling, sampling and analysis techniques, air-quality monitoring, and applications. Diagrams, graphs, and tables of numerical data are provided.

  2. Dispersion modeling of air pollutants in the atmosphere: a review

    NASA Astrophysics Data System (ADS)

    Leelőssy, Ádám; Molnár, Ferenc; Izsák, Ferenc; Havasi, Ágnes; Lagzi, István; Mészáros, Róbert

    2014-09-01

    Modeling of dispersion of air pollutants in the atmosphere is one of the most important and challenging scientific problems. There are several natural and anthropogenic events where passive or chemically active compounds are emitted into the atmosphere. The effect of these chemical species can have serious impacts on our environment and human health. Modeling the dispersion of air pollutants can predict this effect. Therefore, development of various model strategies is a key element for the governmental and scientific communities. We provide here a brief review on the mathematical modeling of the dispersion of air pollutants in the atmosphere. We discuss the advantages and drawbacks of several model tools and strategies, namely Gaussian, Lagrangian, Eulerian and CFD models. We especially focus on several recent advances in this multidisciplinary research field, like parallel computing using graphical processing units, or adaptive mesh refinement.

  3. Atmospheric modeling of air pollution. (Latest citations from the NTIS database). Published Search

    SciTech Connect

    Not Available

    1993-02-01

    The bibliography contains citations concerning the development, validation, and application of mathematical models for air pollution studies of mobile and stationary pollution sources. The models cover a wide range of mathematical complexity, utilizing factors such as terrain features, wake effects, diffusion, atmospheric stability, atmospheric wind, precipitation scavenging, gravitational deposition, atmospheric photochemistry, and urban heat islands. The models are used to support environmental impact studies and effects of proposed emission control strategies. Excluded are models of stratospheric pollution behavior, as applied to high flying aircraft. (Contains 250 citations and includes a subject term index and title list.)

  4. Atmospheric modeling of air pollution. (Latest citations from the NTIS bibliographic database). NewSearch

    SciTech Connect

    Not Available

    1994-11-01

    The bibliography contains citations concerning the development, validation, and application of mathematical models for air pollution studies of mobile and stationary pollution sources. The models cover a wide range of mathematical complexity, utilizing factors such as terrain features, wake effects, diffusion, atmospheric stability, atmospheric wind, precipitation scavenging, gravitational deposition, atmospheric photochemistry, and urban heat islands. The models are used to support environmental impact studies and effects of proposed emission control strategies. Excluded are models of stratospheric pollution behavior, as applied to high flying aircraft. (Contains 250 citations and includes a subject term index and title list.)

  5. Atmospheric modeling of air pollution. (Latest citations from the NTIS Bibliographic database). Published Search

    SciTech Connect

    Not Available

    1993-11-01

    The bibliography contains citations concerning the development, validation, and application of mathematical models for air pollution studies of mobile and stationary pollution sources. The models cover a wide range of mathematical complexity, utilizing factors such as terrain features, wake effects, diffusion, atmospheric stability, atmospheric wind, precipitation scavenging, gravitational deposition, atmospheric photochemistry, and urban heat islands. The models are used to support environmental impact studies and effects of proposed emission control strategies. Excluded are models of stratospheric pollution behavior, as applied to high flying aircraft. (Contains 250 citations and includes a subject term index and title list.)

  6. Atmospheric modeling of air pollution. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1996-03-01

    The bibliography contains citations concerning the development, validation, and application of mathematical models for air pollution studies of mobile and stationary pollution sources. The models cover a wide range of mathematical complexity, utilizing factors such as terrain features, wake effects, diffusion, atmospheric stability, atmospheric wind, precipitation scavenging, gravitational deposition, atmospheric photochemistry, and urban heat islands. The models are used to support environmental impact studies and effects of proposed emission control strategies. Excluded are models of stratospheric pollution behavior, as applied to high flying aircraft.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  7. Students 'Weigh' Atmospheric Pollution.

    ERIC Educational Resources Information Center

    Caporaloni, Marina

    1998-01-01

    Describes a procedure developed by students that measures the mass concentration of particles in a polluted urban atmosphere. Uses a portable fan and filters of various materials. Compares students' data with official data. (DDR)

  8. Appropriate line profiles for radiation modeling in the detection of atmospheric pollutants

    NASA Technical Reports Server (NTRS)

    Tiwari, S. N.

    1973-01-01

    Absorption by Lorentz, Doppler, and Voight lines are compared for a range of atmospheric parameters. It is found that, for the intermediate path lengths, the use of the combined Lorentz-Doppler (Voight) profile is essential in calculating the atmospheric transmittance. A brief review of band models, to approximate the absorption over certain frequency interval, is presented. Expressions for total radiative energy emergent from the atmosphere are given which, with appropriate line or band models, can be used to reduce the data obtained from radiation measurement by an instrument mounted on an aircraft or a satellite. By employing the inversion procedure, the concentration of atmospheric pollutants can be obtained from the measured data.

  9. REPRESENTATION OF ATMOSPHERIC MOTION IN MODELS OF REGIONAL-SCALE AIR POLLUTION

    EPA Science Inventory

    A method is developed for generating ensembles of wind fields for use in regional scale (1000 km) models of transport and diffusion. The underlying objective is a methodology for representing atmospheric motion in applied air pollution models that permits explicit treatment of th...

  10. Uncertainty Modeling of Pollutant Transport in Atmosphere and Aquatic Route Using Soft Computing

    SciTech Connect

    Datta, D.

    2010-10-26

    Hazardous radionuclides are released as pollutants in the atmospheric and aquatic environment (ATAQE) during the normal operation of nuclear power plants. Atmospheric and aquatic dispersion models are routinely used to assess the impact of release of radionuclide from any nuclear facility or hazardous chemicals from any chemical plant on the ATAQE. Effect of the exposure from the hazardous nuclides or chemicals is measured in terms of risk. Uncertainty modeling is an integral part of the risk assessment. The paper focuses the uncertainty modeling of the pollutant transport in atmospheric and aquatic environment using soft computing. Soft computing is addressed due to the lack of information on the parameters that represent the corresponding models. Soft-computing in this domain basically addresses the usage of fuzzy set theory to explore the uncertainty of the model parameters and such type of uncertainty is called as epistemic uncertainty. Each uncertain input parameters of the model is described by a triangular membership function.

  11. a Mesoscale Atmospheric Dispersion Modeling System for Simulations of Topographically Induced Atmospheric Flow and Air Pollution Dispersion.

    NASA Astrophysics Data System (ADS)

    Boybeyi, Zafer

    A mesoscale atmospheric dispersion modeling system has been developed to investigate mesoscale circulations and associated air pollution dispersion, including effects of terrain topography, large water bodies and urban areas. The system is based on a three-dimensional mesoscale meteorological model coupled with two dispersion models (an Eulerian dispersion model and a Lagrangian particle dispersion model). The mesoscale model is hydrostatic and based on primitive equations formulated in a terrain-following coordinate system with a E-varepsilon turbulence closure scheme. The Eulerian dispersion model is based on numerical solution of the advection-diffusion equation to allow one to simulate releases of non-buoyant pollutants (especially from area and volume sources). The Lagrangian particle dispersion model allows one to simulate releases of buoyant pollutants from arbitrary sources (particularly from point and line sources). The air pollution dispersion models included in the system are driven by the meteorological information provided by the mesoscale model. Mesoscale atmospheric circulations associated with sea and lake breezes have been examined using the mesoscale model. A series of model sensitivity studies were performed to investigate the effects of different environmental parameters on these circulations. It was found that the spatial and temporal variation of the sea and lake breeze convergence zones and the associated convective activities depend to a large extent on the direction and the magnitude of the ambient wind. Dispersion of methyl isocyanate gas from the Bhopal accident was investigated using the mesoscale atmospheric dispersion modeling system. A series of numerical experiments were performed to investigate the possible role of the mesoscale circulations on this industrial gas episode. The temporal and spatial variations of the wind and turbulence fields were simulated with the mesoscale model. The dispersion characteristics of the accidental

  12. Deposition of Atmospheric Pollutants

    NASA Astrophysics Data System (ADS)

    Malet, L. M.

    Deposition of Atmospheric Pollutants, containing the proceedings of a colloquium held at Oberursel/Taunus, FRG, November 9-11, 1981, is divided into three main parts: dry deposition; wet deposition; and deposition on plants and vegetation.The 20 articles in the volume permit a fair survey of present-day knowledge and will be a useful tool to all working on the topic. Pollution by deposition of either the dry or wet sort is very insidious; its importance only appears in the long range, when its effects are or are almost irreversible. That is why concern was so long in emerging from decision makers.

  13. Predicting changes of glass optical properties in polluted atmospheric environment by a neural network model

    NASA Astrophysics Data System (ADS)

    Verney-Carron, A.; Dutot, A. L.; Lombardo, T.; Chabas, A.

    2012-07-01

    Soiling results from the deposition of pollutants on materials. On glass, it leads to an alteration of its intrinsic optical properties. The nature and intensity of this phenomenon mirrors the pollution of an environment. This paper proposes a new statistical model in order to predict the evolution of haze (H) (i.e. diffuse/direct transmitted light ratio) as a function of time and major pollutant concentrations in the atmosphere (SO2, NO2, and PM10 (Particulate Matter < 10 μm)). The model was parameterized by using a large set of data collected in European cities (especially, Paris and its suburbs, Athens, Krakow, Prague, and Rome) during field exposure campaigns (French, European, and international programs). This statistical model, called NEUROPT-Glass, comes from an artificial neural network with two hidden layers and uses a non-linear parametric regression named Multilayer Perceptron (MLP). The results display a high determination coefficient (R2 = 0.88) between the measured and the predicted hazes and minimizes the dispersion of data compared to existing multilinear dose-response functions. Therefore, this model can be used with a great confidence in order to predict the soiling of glass as a function of time in world cities with different levels of pollution or to assess the effect of pollution reduction policies on glass soiling problems in urban environments.

  14. Modeling the effects of a solid barrier on pollutant dispersion under various atmospheric stability conditions

    NASA Astrophysics Data System (ADS)

    Steffens, Jonathan T.; Heist, David K.; Perry, Steven G.; Zhang, K. Max

    2013-04-01

    There is a growing need for developing mitigation strategies for near-road air pollution. Roadway design is being considered as one of the potential options. Particularly, it has been suggested that sound barriers, erected to reduce noise, may prove effective at decreasing pollutant concentrations. However, there is still a lack of mechanistic understanding of how solid barriers affect pollutant transport, especially under a variety of meteorological conditions. In this study, we utilized the Comprehensive Turbulent Aerosol Dynamics and Gas Chemistry (CTAG) model to simulate the spatial gradients of SF6 concentrations behind a solid barrier under a variety of atmospheric stability conditions collected during the Near Road Tracer Study (NRTS08). We employed two different CFD models, RANS and LES. A recirculation zone, characterized by strong mixing, forms in the wake of a barrier. It is found that this region is important for accurately predicting pollutant dispersion, but is often insufficiently resolved by the less complex RANS model. The RANS model was found to perform adequately away from the leading edge of the barrier. The LES model, however, performs consistently well at all flow locations. Therefore, the LES model will make a significant improvement compared to the RANS model in regions of strong recirculating flow or edge effects. Our study suggests that advanced simulation tools can potentially provide a variety of numerical experiments that may prove useful for roadway design communities to intelligently design roadways, making effective use of roadside barriers.

  15. The model SIRANE for atmospheric urban pollutant dispersion; part I, presentation of the model

    NASA Astrophysics Data System (ADS)

    Soulhac, Lionel; Salizzoni, Pietro; Cierco, F.-X.; Perkins, Richard

    2011-12-01

    In order to control and manage urban air quality, public authorities require an integrated approach that incorporates direct measurements and modelling of mean pollutant concentrations. These have to be performed by means of operational modelling tools, that simulate the transport of pollutants within and above the urban canopy over a large number of streets. The operational models must be able to assess rapidly a large variety of situations and with limited computing resources. SIRANE is an operational urban dispersion model based on a simplified description of the urban geometry that adopts parametric relations for the pollutant transfer phenomena within and out of the urban canopy. The streets in a city district are modelled as a network of connected street segments. The flow within each street is driven by the component of the external wind parallel to the street, and the pollutant is assumed to be uniformly mixed within the street. The model contains three main mechanisms for transport in and out of a street: advection along the street axis, diffusion across the interface between the street and the overlying air flow and exchanges with other streets at street intersections. The dispersion of pollutants advected or diffused out of the streets is taken into account using a Gaussian plume model, with the standard deviations σ y and σ z parameterised by the similarity theory. The input data for the final model are the urban geometry, the meteorological parameters, the background concentration of pollutants advected into the model domain by the wind and the emissions within each street in the network.

  16. Modeling short-term concentration fluctuations of semi-volatile pollutants in the soil-plant-atmosphere system.

    PubMed

    Bao, Zhongwen; Haberer, Christina M; Maier, Uli; Beckingham, Barbara; Amos, Richard T; Grathwohl, Peter

    2016-11-01

    Temperature changes can drive cycling of semi-volatile pollutants between different environmental compartments (e.g. atmosphere, soil, plants). To evaluate the impact of daily temperature changes on atmospheric concentration fluctuations we employed a physically based model coupling soil, plants and the atmosphere, which accounts for heat transport, effective gas diffusion, sorption and biodegradation in the soil as well as eddy diffusion and photochemical oxidation in the atmospheric boundary layer of varying heights. The model results suggest that temperature-driven re-volatilization and uptake in soils cannot fully explain significant diurnal concentration fluctuations of atmospheric pollutants as for example observed for polychlorinated biphenyls (PCBs). This holds even for relatively low water contents (high gas diffusivity) and high sorption capacity of the topsoil (high organic carbon content and high pollutant concentration in the topsoil). Observed concentration fluctuations, however, can be easily matched if a rapidly-exchanging environmental compartment, such as a plant layer, is introduced. At elevated temperatures, plants release organic pollutants, which are rapidly distributed in the atmosphere by eddy diffusion. For photosensitive compounds, e.g. some polycyclic aromatic hydrocarbons (PAHs), decreasing atmospheric concentrations would be expected during daytime for the bare soil scenario. This decline is buffered by a plant layer, which acts as a ground-level reservoir. The modeling results emphasize the importance of a rapidly-exchanging compartment above ground to explain short-term atmospheric concentration fluctuations. PMID:27341116

  17. Interception of wet deposited atmospheric pollutants by herbaceous vegetation: Data review and modelling.

    PubMed

    Gonze, M-A; Sy, M M

    2016-09-15

    Better understanding and predicting interception of wet deposited pollutants by vegetation remains a key issue in risk assessment studies of atmospheric pollution. We develop different alternative models, following either empirical or semi-mechanistic descriptions, on the basis of an exhaustive dataset consisting of 440 observations obtained in controlled experiments, from 1970 to 2014, for a wide variety of herbaceous plants, radioactive substances and rainfall conditions. The predictive performances of the models and the uncertainty/variability of the parameters are evaluated under Hierarchical Bayesian modelling framework. It is demonstrated that the variability of the interception fraction is satisfactorily explained and quite accurately modelled by a process-based alternative in which absorption of ionic substances onto the foliage surfaces is determined by their electrical valence. Under this assumption, the 95% credible interval of the predicted interception fraction encompasses 81% of the observations, including situations where either plant biomass or rainfall intensity are unknown. This novel approach is a serious candidate to challenge existing empirical relationships in radiological or chemical risk assessment tools. PMID:27156215

  18. Atmospheric modeling of air pollution. 1979-May, 1980 (a bibliography with abstracts). Report for 1979-May 80

    SciTech Connect

    Carrigan, B.

    1980-06-01

    Lower atmospheric modeling of air pollution from both mobile and stationary sources are covered in the bibliography. Models cover local diffusion, urban heat islands, precipitation washout, worldwide diffusion, climatology, and smog. Stratospheric modeling concerning supersonic aircraft are excluded. (This updated bibliography contains 130 abstracts, 88 of which are new entries to the previous edition.)

  19. Atmospheric modeling of air pollution. 1979-October 1981 (Citations from the NTIS Data Base). Report for 1979-October 1981

    SciTech Connect

    Not Available

    1981-11-01

    Lower atmospheric modeling of air pollution from both mobile and stationary sources are covered in the bibliography. Models cover local diffusion, urban heat islands, precipitation washout, worldwide diffusion, climatology, and smog. Stratospheric modeling concerning supersonic aircraft are excluded. (This updated bibliography contains 248 citations, 118 of which are new entries to the previous edition.)

  20. Atmospheric modeling of air pollution. 1977-78 (a bibliography with abstracts). Report for 1977-1978

    SciTech Connect

    Carrigan, B.

    1980-06-01

    Lower atmospheric modeling of air pollution from both mobile and stationary sources are covered in the bibliography. Models cover local diffusion, urban heat islands, precipitation washout, worldwide diffusion, climatology, and smog. Stratospheric modeling concerning supersonic aircraft are excluded. (This updated bibliography contains 216 abstracts, none of which are new entries to the previous edition.)

  1. Mobile Instruments Measure Atmospheric Pollutants

    NASA Technical Reports Server (NTRS)

    2009-01-01

    As a part of NASA's active research of the Earth s atmosphere, which has included missions such as the Atmospheric Laboratory of Applications and Science (ATLAS, launched in 1992) and the Total Ozone Mapping Spectrometer (TOMS, launched on the Earth Probe satellite in 1996), the Agency also performs ground-based air pollution research. The ability to measure trace amounts of airborne pollutants precisely and quickly is important for determining natural patterns and human effects on global warming and air pollution, but until recent advances in field-grade spectroscopic instrumentation, this rapid, accurate data collection was limited and extremely difficult. In order to understand causes of climate change and airborne pollution, NASA has supported the development of compact, low power, rapid response instruments operating in the mid-infrared "molecular fingerprint" portion of the electromagnetic spectrum. These instruments, which measure atmospheric trace gases and airborne particles, can be deployed in mobile laboratories - customized ground vehicles, typically - to map distributions of pollutants in real time. The instruments must be rugged enough to operate rapidly and accurately, despite frequent jostling that can misalign, damage, or disconnect sensitive components. By measuring quickly while moving through an environment, a mobile laboratory can correlate data and geographic points, revealing patterns in the environment s pollutants. Rapid pollutant measurements also enable direct determination of pollutant sources and sinks (mechanisms that remove greenhouse gases and pollutants), providing information critical to understanding and managing atmospheric greenhouse gas and air pollutant concentrations.

  2. Forecasting human exposure to atmospheric pollutants in Portugal - A modelling approach

    NASA Astrophysics Data System (ADS)

    Borrego, C.; Sá, E.; Monteiro, A.; Ferreira, J.; Miranda, A. I.

    2009-12-01

    Air pollution has become one main environmental concern because of its known impact on human health. Aiming to inform the population about the air they are breathing, several air quality modelling systems have been developed and tested allowing the assessment and forecast of air pollution ambient levels in many countries. However, every day, an individual is exposed to different concentrations of atmospheric pollutants as he/she moves from and to different outdoor and indoor places (the so-called microenvironments). Therefore, a more efficient way to prevent the population from the health risks caused by air pollution should be based on exposure rather than air concentrations estimations. The objective of the present study is to develop a methodology to forecast the human exposure of the Portuguese population based on the air quality forecasting system available and validated for Portugal since 2005. Besides that, a long-term evaluation of human exposure estimates aims to be obtained using one-year of this forecasting system application. Additionally, a hypothetical 50% emission reduction scenario has been designed and studied as a contribution to study emission reduction strategies impact on human exposure. To estimate the population exposure the forecasting results of the air quality modelling system MM5-CHIMERE have been combined with the population spatial distribution over Portugal and their time-activity patterns, i.e. the fraction of the day time spent in specific indoor and outdoor places. The population characterization concerning age, work, type of occupation and related time spent was obtained from national census and available enquiries performed by the National Institute of Statistics. A daily exposure estimation module has been developed gathering all these data and considering empirical indoor/outdoor relations from literature to calculate the indoor concentrations in each one of the microenvironments considered, namely home, office/school, and other

  3. Source apportionment of atmospheric mercury pollution in China using the GEOS-Chem model.

    PubMed

    Wang, Long; Wang, Shuxiao; Zhang, Lei; Wang, Yuxuan; Zhang, Yanxu; Nielsen, Chris; McElroy, Michael B; Hao, Jiming

    2014-07-01

    China is the largest atmospheric mercury (Hg) emitter in the world. Its Hg emissions and environmental impacts need to be evaluated. In this study, China's Hg emission inventory is updated to 2007 and applied in the GEOS-Chem model to simulate the Hg concentrations and depositions in China. Results indicate that simulations agree well with observed background Hg concentrations. The anthropogenic sources contributed 35-50% of THg concentration and 50-70% of total deposition in polluted regions. Sensitivity analysis was performed to assess the impacts of mercury emissions from power plants, non-ferrous metal smelters and cement plants. It is found that power plants are the most important emission sources in the North China, the Yangtze River Delta (YRD) and the Pearl River Delta (PRD) while the contribution of non-ferrous metal smelters is most significant in the Southwest China. The impacts of cement plants are significant in the YRD, PRD and Central China. PMID:24768744

  4. A new conceptual model for quantifying transboundary contribution of atmospheric pollutants in the East Asian Pacific rim region.

    PubMed

    Lai, I-Chien; Lee, Chon-Lin; Huang, Hu-Ching

    2016-03-01

    Transboundary transport of air pollution is a serious environmental concern as pollutant affects both human health and the environment. Many numerical approaches have been utilized to quantify the amounts of pollutants transported to receptor regions, based on emission inventories from possible source regions. However, sparse temporal-spatial observational data and uncertainty in emission inventories might make the transboundary transport contribution difficult to estimate. This study presents a conceptual quantitative approach that uses transport pathway classification in combination with curve fitting models to simulate an air pollutant concentration baseline for pollution background concentrations. This approach is used to investigate the transboundary transport contribution of atmospheric pollutants to a metropolitan area in the East Asian Pacific rim region. Trajectory analysis categorized pollution sources for the study area into three regions: East Asia, Southeast Asia, and Taiwan cities. The occurrence frequency and transboundary contribution results suggest the predominant source region is the East Asian continent. This study also presents an application to evaluate heavy pollution cases for health concerns. This new baseline construction model provides a useful tool for the study of the contribution of transboundary pollution delivered to receptors, especially for areas deficient in emission inventories and regulatory monitoring data for harmful air pollutants. PMID:26760713

  5. Remote measurement of atmospheric pollutants

    NASA Technical Reports Server (NTRS)

    Allario, F.; Hoell, J.; Seals, R. K.

    1979-01-01

    The concentration and vertical distribution of atmospheric ammonia and ozone are remotely sensed, using dual-C02-laser multichannel infrared Heterodyne Spectrometer (1HS). Innovation makes atmospheric pollution measurements possible with nearly-quantum-noise-limited sensitivity and ultrafine spectral resolution.

  6. Global atmospheric emissions and transport of polycyclic aromatic hydrocarbons: Evaluation of modeling and transboundary pollution

    NASA Astrophysics Data System (ADS)

    Shen, Huizhong; Tao, Shu

    2014-05-01

    Global atmospheric emissions of 16 polycyclic aromatic hydrocarbons (PAHs) from 69 major sources were estimated for a period from 1960 to 2030. Regression models and a technology split method were used to estimated country and time specific emission factors, resulting in a new estimate of PAH emission factor variation among different countries and over time. PAH emissions in 2007 were spatially resolved to 0.1° × 0.1° grids based on a newly developed global high-resolution fuel combustion inventory (PKU-FUEL-2007). MOZART-4 (The Model for Ozone and Related Chemical Tracers, version 4) was applied to simulate the global tropospheric transport of Benzo(a)pyrene, one of the high molecular weight carcinogenic PAHs, at a horizontal resolution of 1.875° (longitude) × 1.8947° (latitude). The reaction with OH radical, gas/particle partitioning, wet deposition, dry deposition, and dynamic soil/ocean-air exchange of PAHs were considered. The simulation was validated by observations at both background and non-background sites, including Alert site in Canadian High Arctic, EMEP sites in Europe, and other 254 urban/rural sites reported from literatures. Key factors effecting long-range transport of BaP were addressed, and transboundary pollution was discussed.

  7. Modeling and evaluation of urban pollution events of atmospheric heavy metals from a large Cu-smelter.

    PubMed

    Chen, Bing; Stein, Ariel F; Castell, Nuria; Gonzalez-Castanedo, Yolanda; Sanchez de la Campa, A M; de la Rosa, J D

    2016-01-01

    Metal smelting and processing are highly polluting activities that have a strong influence on the levels of heavy metals in air, soil, and crops. We employ an atmospheric transport and dispersion model to predict the pollution levels originated from the second largest Cu-smelter in Europe. The model predicts that the concentrations of copper (Cu), zinc (Zn), and arsenic (As) in an urban area close to the Cu-smelter can reach 170, 70, and 30 ng m−3, respectively. The model captures all the observed urban pollution events, but the magnitude of the elemental concentrations is predicted to be lower than that of the observed values; ~300, ~500, and ~100 ng m−3 for Cu, Zn, and As, respectively. The comparison between model and observations showed an average correlation coefficient of 0.62 ± 0.13. The simulation shows that the transport of heavy metals reaches a peak in the afternoon over the urban area. The under-prediction in the peak is explained by the simulated stronger winds compared with monitoring data. The stronger simulated winds enhance the transport and dispersion of heavy metals to the regional area, diminishing the impact of pollution events in the urban area. This model, driven by high resolution meteorology (2 km in horizontal), predicts the hourly-interval evolutions of atmospheric heavy metal pollutions in the close by urban area of industrial hotspot. PMID:26352643

  8. Atmospheric Chemistry and Air Pollution

    DOE PAGESBeta

    Gaffney, Jeffrey S.; Marley, Nancy A.

    2003-01-01

    Atmospheric chemistry is an important discipline for understanding air pollution and its impacts. This mini-review gives a brief history of air pollution and presents an overview of some of the basic photochemistry involved in the production of ozone and other oxidants in the atmosphere. Urban air quality issues are reviewed with a specific focus on ozone and other oxidants, primary and secondary aerosols, alternative fuels, and the potential for chlorine releases to amplify oxidant chemistry in industrial areas. Regional air pollution issues such as acid rain, long-range transport of aerosols and visibility loss, and the connections of aerosols to ozonemore » and peroxyacetyl nitrate chemistry are examined. Finally, the potential impacts of air pollutants on the global-scale radiative balances of gases and aerosols are discussed briefly.« less

  9. Model assessment of atmospheric pollution control schemes for critical emission regions

    NASA Astrophysics Data System (ADS)

    Zhai, Shixian; An, Xingqin; Liu, Zhao; Sun, Zhaobin; Hou, Qing

    2016-01-01

    In recent years, the atmospheric environment in portions of China has become significantly degraded and the need for emission controls has become urgent. Because more international events are being planned, it is important to implement air quality assurance targeted at significant events held over specific periods of time. This study sets Yanqihu (YQH), Beijing, the location of the 2014 Beijing APEC (Asia-Pacific Economic Cooperation) summit, as the target region. By using the atmospheric inversion model FLEXPART, we determined the sensitive source zones that had the greatest impact on the air quality of the YQH region in November 2012. We then used the air-quality model Models-3/CMAQ and a high-resolution emissions inventory of the Beijing-Tianjian-Hebei region to establish emission reduction tests for the entire source area and for specific sensitive source zones. This was achieved by initiating emission reduction schemes at different ratios and different times. The results showed that initiating a moderate reduction of emissions days prior to a potential event is more beneficial to the air quality of Beijing than initiating a high-strength reduction campaign on the day of the event. The sensitive source zone of Beijing (BJ-Sens) accounts for 54.2% of the total source area of Beijing (BJ), but its reduction effect reaches 89%-100% of the total area, with a reduction efficiency 1.6-1.9 times greater than that of the entire area. The sensitive source zone of Huabei (HuaB-Sens.) only represents 17.6% of the total area of Huabei (HuaB), but its emission reduction effect reaches 59%-97% of the entire area, with a reduction efficiency 4.2-5.5 times greater than that of the total area. The earlier that emission reduction measures are implemented, the greater the effect they have on preventing the transmission of pollutants. In addition, expanding the controlling areas to sensitive provinces and cities around Beijing (HuaB-sens) can significantly accelerate the reduction

  10. Atmospheric modeling of air pollution, January 1988-July 1991 (Citations from the NTIS Data Base). Rept. for Jan 88-Jul 91

    SciTech Connect

    Not Available

    1991-07-01

    The bibliography contains citations concerning the development, validation, and application of mathematical models for air pollution studies of mobile and stationary pollution sources. The models cover a wide range of mathematical complexity, utilizing factors such as terrain features, wake effects, diffusion, atmospheric stability, atmospheric wind, precipitation scavenging, gravitational deposition, atmospheric photochemistry, and urban heat islands. The models are used to support environmental impact studies and effects of proposed emission control strategies. Excluded are models of stratospheric pollution behavior, as applied to high flying aircraft. (Contains 159 citations with title list and subject index.)

  11. Atmospheric modeling of air pollution. September 1984-March 1988 (Citations from the NTIS data base). Report for September 1984-March 1988

    SciTech Connect

    Not Available

    1988-03-01

    This bibliography contains citations concerning the development, validation, and application of mathematical models for air-pollution studies of mobile and stationary pollution sources. The models cover a wide range of mathematical complexity, utilizing factors such as terrain features, wake effects, diffusion, atmospheric stability, atmospheric wind, precipitation scavenging, gravitational deposition, atmospheric photochemistry, and urban heat islands. The models are used to support environmental impact studies and effects of proposed emission control strategies. Excluded are models of stratospheric pollution behavior, as applied to high flying aircraft. (This updated bibliography contains 352 citations, 104 of which are new entries to the previous edition.)

  12. Atmospheric modeling of air pollution. April 1988-April 1989 (Citations from the NTIS data base). Report for April 1988-April 1989

    SciTech Connect

    Not Available

    1989-05-01

    This bibliography contains citations concerning the development, validation, and application of mathematical models for air-pollution studies of mobile and stationary pollution sources. The models cover a wide range of mathematical complexity, utilizing factors such as terrain features, wake effects, diffusion, atmospheric stability, atmospheric wind, precipitation scavenging, gravitational deposition, atmospheric photochemistry, and urban heat islands. The models are used to support environmental-impact studies and effects of proposed emission-control strategies. Excluded are models of stratospheric pollution behavior, as applied to high-flying aircraft. (This updated bibliography contains 105 citations, all of which are new entries to the previous edition.)

  13. Atmospheric modeling of air pollution. April 1988-November 1989 (Citations from the NTIS data base). Report for April 1988-November 1989

    SciTech Connect

    Not Available

    1989-12-01

    This bibliography contains citations concerning the development, validation, and application of mathematical models for air-pollution studies of mobile and stationary pollution sources. The models cover a wide range of mathematical complexity, utilizing factors such as terrain features, wake effects, diffusion, atmospheric stability, atmospheric wind, precipitation scavenging, gravitational deposition, atmospheric photochemistry, and urban heat islands. The models are used to support environmental-impact studies and effects of proposed emission-control strategies. Excluded are models of stratospheric pollution behavior, as applied to high-flying aircraft. (This updated bibliography contains 138 citations, 33 of which are new entries to the previous edition.)

  14. Atmospheric modeling of air pollution. September 1984-March 1988 (Citations from the NTIS data base). Report for September 1984-March 1988

    SciTech Connect

    Not Available

    1989-05-01

    This bibliography contains citations concerning the development, validation, and application of mathematical models for air-pollution studies of mobile and stationary pollution sources. The models cover a wide range of mathematical complexity, utilizing factors such as terrain features, wake effects, diffusion, atmospheric stability, atmospheric wind, precipitation scavenging, gravitational deposition, atmospheric photochemistry, and urban heat islands. The models are used to support environmental-impact studies and effects of proposed emission-control strategies. Excluded are models of stratospheric pollution behavior, as applied to high-flying aircraft. (This updated bibliography contains 352 citations, none of which are new entries to the previous edition.)

  15. Clean Air Slots Amid Atmospheric Pollution

    NASA Technical Reports Server (NTRS)

    Hobbs, Peter V.

    2002-01-01

    This article investigates the mechanism for those layers in the atmosphere that are free of air borne pollution even though the air above and below them carry pollutants. Atmospheric subsidence is posed as a mechanism for this phenomenon.

  16. Modelling and predicting urban atmospheric pollutants in the Aosta Valley region of Italy using a site-optimised model

    NASA Astrophysics Data System (ADS)

    Dirks, Kim N.; Nanni, Alessandro; Dirks, Vincent I.

    2006-01-01

    An effective simple site-optimised urban air pollution model for predicting CO, PM10, NO and NO2 concentrations is developed for the topographically complex region of the Aosta Valley in Italy. The good results suggest that such a model could be used to downscale mesoscale-forecasted surface conditions to give real-time site-specific pollution predictions.

  17. Atmospheric pollution and lung cancer.

    PubMed Central

    Doll, R

    1978-01-01

    Lung cancer is consistently more common in urban areas than in rural. The excess cannot be accounted for by specific occupational hazards but some of it might be due to the presence of carcinogens in urban air. The excess cannot be wholly due to such agents, because the excess in nonsmokers is small and variable. Cigarette consumption has also been greater in urban areas, but it is difficult to estimate how much of the excess it can account for. Occupational studies confirm that pollutants present in town air are capable of causing lung cancer in man and suggest that the pollutants and cigarette smoke act synergistically. The trends in the mortality from lung cancer in young and middle-aged men in England and Wales provide uncertain evidence but support the belief that atmospheric pollution has contributed to the production of the disease. In the absence of cigarette smoking, the combined effect of all atmospheric carcinogens is not responsible for more than about 5 cases of lung cancer per 100,000 persons per year in European populations. PMID:648488

  18. Archives of Atmospheric Lead Pollution

    NASA Astrophysics Data System (ADS)

    Weiss, Dominik; Shotyk, William; Kempf, Oliver

    Environmental archives such as peat bogs, sediments, corals, trees, polar ice, plant material from herbarium collections, and human tissue material have greatly helped to assess both ancient and recent atmospheric lead deposition and its sources on a regional and global scale. In Europe detectable atmospheric lead pollution began as early as 6000years ago due to enhanced soil dust and agricultural activities, as studies of peat bogs reveal. Increased lead emissions during ancient Greek and Roman times have been recorded and identified in many long-term archives such as lake sediments in Sweden, ice cores in Greenland, and peat bogs in Spain, Switzerland, the United Kingdom, and the Netherlands. For the period since the Industrial Revolution, other archives such as corals, trees, and herbarium collections provide similar chronologies of atmospheric lead pollution, with periods of enhanced lead deposition occurring at the turn of the century and since 1950. The main sources have been industry, including coal burning, ferrous and nonferrous smelting, and open waste incineration until c.1950 and leaded gasoline use since 1950. The greatest lead emissions to the atmosphere all over Europe occurred between 1950 and 1980 due to traffic exhaust. A marked drop in atmospheric lead fluxes found in most archives since the 1980s has been attributed to the phasing out of leaded gasoline. The isotope ratios of lead in the various archives show qualitatively similar temporal changes, for example, the immediate response to the introduction and phasing out of leaded gasoline. Isotope studies largely confirm source assessments based on lead emission inventories and allow the contributions of various anthropogenic sources to be calculated.

  19. [Current data on atmospheric pollutions].

    PubMed

    Festy, B; Petit-Coviaux, F; Le Moullec, Y

    1991-01-01

    Atmospheric pollutions (AP) are very important for human health and ecological equilibrium. They may be natural or anthropogenic and in this later case they can appear outdoor or indoor. Urban air pollution is the most known form of AP. Its main sources are industries, individual and collective heating and now mainly automobile traffic in most cities. Classical AP indicators are SO2, particles, NOx, CO and Pb measured in networks. Important factors of AP are amounts of pollutants emitted and local climatic and meteorological characteristics. Health effects of AP peaks and of AP background levels are not well known. But generally, mean AP levels of SO2 and particles decreased in the last years in most towns as the consequence of collective actions on the three main sources of AP and on fuels, emission and immission levels; but more is wanted about motor-cars. Progress are necessary for limitation of three major ecological risks: "acid-rain" (SO2 and NOx derivatives, ozone,...) which participates in lake and forest attacks; "green house" effects whose air CO2 concentration increase is the main responsible, and stratospheric ozone depletion mainly due to freons (CFC); the consequences of these two last phenomena are not well known but ecological and health risk exist. Besides, indoor air pollution (IAP) is very important because we live more than 20 h a day indoor. IAP may be occupational (a lot of chemical or biological agents) or not. In the later case air pollutants are very various: CO, NOx and particles from heating or cooking, formaldehyde from wood glue, plywood or urea-formol foams, radon and derivatives in some granitic countries, odd jobs products, cosmetics, aero-allergens of chemical or biological origins, microbes,... Environmental tobacco smoke (ETS) is also an important pollutant complex. Risks of IAP are real or potential: acute risk is obvious for CO, aero-allergens, formaldehyde, NOx,...); irritations are produced by ETS, formaldehyde, solvants

  20. Prognostic Modeling of Long-Range Atmospheric Pollutant Transport for ETEX

    SciTech Connect

    Griggs, D.P.

    1995-09-14

    The ability to forecast the transport and diffusion of airborne contaminants over long distances is vital when responding to nuclear emergencies. Atmospheric models used in such emergency response applications must be able to include the effects of the evolving synoptic weather systems in a timely manner. The European Tracer EXperiment (ETEX), conducted in October and November 1994, is designed to evaluate the performance of such models. In addition to the tracer experiments, concurrent real-time modeling exercises were conducted by some 24 organizations world-wide, including the Savannah River Technology Center (SRTC) of the U.S. Department of Energy`s Savannah River Site. This paper describes the forecast results obtained by atmospheric modelers at SRTC in applying an advanced three-dimensional modeling system to forecast tracer transport and diffusion during ETEX. Forecast results from the first of two tracer experiments are presented in this preprint paper. Data for the tracer gas concentrations is not yet available; however, surface and sounding data are available from the time periods of the releases. This paper will focus on the evaluation of the forecasts in light of the surface wind data, and relate the forecast evaluations to the differences in the tracer gas dispersion predicted using these forecasts. Plume transport and diffusion results were reported previously.

  1. Acid–base chemical reaction model for nucleation rates in the polluted atmospheric boundary layer

    PubMed Central

    Chen, Modi; Titcombe, Mari; Jiang, Jingkun; Jen, Coty; Kuang, Chongai; Fischer, Marc L.; Eisele, Fred L.; Siepmann, J. Ilja; Hanson, David R.; Zhao, Jun; McMurry, Peter H.

    2012-01-01

    Climate models show that particles formed by nucleation can affect cloud cover and, therefore, the earth's radiation budget. Measurements worldwide show that nucleation rates in the atmospheric boundary layer are positively correlated with concentrations of sulfuric acid vapor. However, current nucleation theories do not correctly predict either the observed nucleation rates or their functional dependence on sulfuric acid concentrations. This paper develops an alternative approach for modeling nucleation rates, based on a sequence of acid–base reactions. The model uses empirical estimates of sulfuric acid evaporation rates obtained from new measurements of neutral molecular clusters. The model predicts that nucleation rates equal the sulfuric acid vapor collision rate times a prefactor that is less than unity and that depends on the concentrations of basic gaseous compounds and preexisting particles. Predicted nucleation rates and their dependence on sulfuric acid vapor concentrations are in reasonable agreement with measurements from Mexico City and Atlanta. PMID:23091030

  2. Radon as a tool for characterising atmospheric stability effects on air pollution concentrations in model evaluation studies

    NASA Astrophysics Data System (ADS)

    Chambers, Scott; Williams, Alastair; Crawford, Jagoda; Griffiths, Alan

    2015-04-01

    A clearer understanding of the variability in near-surface concentrations of pollutants in urban regions is essential for improving the predictive abilities of chemical transport models as well as identifying the need for (and assessing the efficacy of) emission mitigation strategies. Pollutant concentrations in the atmospheric boundary layer (ABL) are a complex function of many factors, including: source strengths and distribution, local meteorology and air chemistry. On short (sub-diurnal) timescales, the extent of the vertical column within which emissions mix usually has the largest influence on measured concentrations, and the depth of this mixing volume is in turn closely related to wind speed and the thermal stability of the ABL. Continuous hourly observations of the ubiquitous, surface-emitted, passive tracer radon-222 provide a powerful alternative to contemporary meteorological techniques for assessing stability effects on urban pollutants, because radon's concentration is closely matched with pollution transport processes at the surface. Here we outline a technique by which single-height, near-surface (<20m) radon observations can be conditioned to derive a multi-category stability classification scheme for urban pollution monitoring to provide benchmarking tools for local- to regional- chemical transport model evaluations. Efficacy of the radon-based classification scheme is compared to that based on conventional Pasquil-Gifford "turbulence" and "radiation" schemes. Lastly, we apply the radon-based classification scheme to nocturnal mixing height estimates calculated from the diurnal radon accumulation time series, and provide insight to the range of nocturnal mixing depths expected for each of the stability classes.

  3. Lagrangian stochastic modeling of pollutant dispersion in the turbulent atmospheric boundary layer - application to an urban area over complex terrain

    NASA Astrophysics Data System (ADS)

    Fattal, Eyal; Gavze, Ehud

    2014-05-01

    The modeling of pollutant dispersion in the atmospheric boundary layer depends on an adequate description of the turbulent processes. Since turbulence is a multi-scale phenomenon characterized by a high degree of disorder, a statistical approach is needed. Among the statistical approaches, Lagrangian stochastic particle models provide a well established theoretical framework for the description of pollutant dispersion in different atmospheric boundary layer scenarios. Usually turbulent structure in the surface layer is described in terms of Monin-Obukhov similarity theory (MOST) using universal relationships between scaling parameters. These relationships have been shown to be valid in the case of horizontal homogeneity for stationary turbulence. The description of the turbulent processes above rough surfaces, such as over canopies, is a more complex case. For the urban canopy it was found that under developed stationary turbulence conditions MOST relations are approximately valid (in some cases, with extensions). An even more complex case is that of rough surfaces over topography, as no similarity theory has been established to properly describe the turbulence exchange over heterogeneous surfaces in complex terrain. We show Lagrangian stochastic model simulations based on MOST against measurements in urban canopy over complex terrain. Comparison gives good agreement with direct tracer measurements, in cases of neutral and convective stratifications. It is shown that in conditions of developed stationary turbulence, at most areas, there is in an agreement with MOST predictions. However, in very low wind conditions the turbulent nocturnal boundary layer is not necessarily stationary and is spatially non-homogeneous. This results in larger horizontal velocity standard deviation than expected in regular stable regime, as manifested in the pollutant pattern.

  4. KINETIC STUDIES OF SIMULATED POLLUTED ATMOSPHERES

    EPA Science Inventory

    The kinetics and reaction mechanisms of several important atmospheric contaminants - SO2, formaldehyde, nitrous acid, and the nitrosamines - were assessed to help quantify some key aspects of the chemistry of polluted atmospheres. The reactions and lifetimes of excited sulfur dio...

  5. Modeling the effects of a solid barrier on pollutant dispersion under various atmospheric stability conditions

    EPA Science Inventory

    There is a growing need for developing mitigation strategies for near-road air pollution. Roadway design is being considered as one of the potential options. Particularly, it has been suggested that sound barriers, erected to reduce noise, may prove effective at decreasing pollut...

  6. Atmospheric Modeling

    EPA Science Inventory

    Although air quality models have been applied historically to address issues specific to ambient air quality standards (i.e., one criteria pollutant at a time) or welfare (e.g.. acid deposition or visibility impairment). they are inherently multipollutant based. Therefore. in pri...

  7. Monitoring environmental pollution by atmospheric corrosion

    SciTech Connect

    Al-Kharafi, F.M.; Ismail, M.I.

    1988-01-01

    Atmospheric pollution is monitored by outdoor exposure of several commercial alloys including steel, Al, Cu, and brass (Cu-30Zu) alloys. Three districts of Kuwait were selected for this study including of residential, industrial, and marine areas. The atmospheric pollution level could be monitored directly by observation of the corrosion of the test alloys.

  8. Infrared band absorptance correlations and applications to nongray radiation. [mathematical models of absorption spectra for nongray atmospheres in order to study air pollution

    NASA Technical Reports Server (NTRS)

    Tiwari, S. N.; Manian, S. V. S.

    1976-01-01

    Various mathematical models for infrared radiation absorption spectra for atmospheric gases are reviewed, and continuous correlations for the total absorptance of a wide band are presented. Different band absorptance correlations were employed in two physically realistic problems (radiative transfer in gases with internal heat source, and heat transfer in laminar flow of absorbing-emitting gases between parallel plates) to study their influence on final radiative transfer results. This information will be applied to the study of atmospheric pollutants by infrared radiation measurement.

  9. Fire risk and air pollution assessment during the 2007 wildfire events in Greece using the COSMO-ART atmospheric model

    NASA Astrophysics Data System (ADS)

    Athanasopoulou, E.; Giannakopoulos, C.; Vogel, H.; Rieger, D.; Knote, C.; Hatzaki, M.; Vogel, B.; Karali, A.

    2012-04-01

    During 2007, Greece experienced an extreme summer and the worst natural hazard in its modern history. Soil dehydration, following a prolonged dry period in combination with hot temperatures and strong winds, yielded favorable conditions for the ignition and spread of wild fires that burnt approximately 200,000 ha of vegetated land (Founda and Gianakopoulos, 2009; Sifakis et al., 2011). The relationship between meteorology and fire potential can be provided by the Canadian Fire Weather Index (FWI), which is already found applicable in the fire activity of the Mediterranean region (Carvalho et al., 2008). However, lack of meteorological data or remote fire spots can be sources of uncertainties for fire risk estimation. In addition to the direct fire damage, these fires produced large quantities of gaseous air pollutants and particles (PM10) dispersed over the area of Greece. Indeed, PM10 concentration measurements showed two pollution episodes over Athens during late August and early September, 2007 (Liu et al., 2009). Nevertheless, these measurements neither show the large spatial extent of fire effects nor reveal its important role on atmospheric chemistry. In the current study, the application of the atmospheric model COSMO-ART is used to investigate the issues addressed above. COSMO-ART (Vogel et al. 2009) is a regional chemistry transport model (ART stands for Aerosols and Reactive Trace gases) online-coupled to the COSMO regional numerical weather prediction and climate model (Baldauf et al. 2011). The current simulations are performed between August 15 and September 15 over Greece with a horizontal resolution of 2.8 km and a vertical extend up to 20 km. The initial and boundary meteorological conditions are derived from a coarser COSMO simulation performed by the German Weather Service. Fire emissions are retrieved from the Global Fire Emissions Database version 3 (van der Werf et al., 2010). The anthropogenic emission database used is the TNO/MACC (Kuenen et

  10. Modelling pollutants dispersion and plume rise from large hydrocarbon tank fires in neutrally stratified atmosphere

    NASA Astrophysics Data System (ADS)

    Argyropoulos, C. D.; Sideris, G. M.; Christolis, M. N.; Nivolianitou, Z.; Markatos, N. C.

    2010-02-01

    Petrochemical industries normally use storage tanks containing large amounts of flammable and hazardous substances. Therefore, the occurrence of a tank fire, such as the large industrial accident on 11th December 2005 at Buncefield Oil Storage Depots, is possible and usually leads to fire and explosions. Experience has shown that the continuous production of black smoke from these fires due to the toxic gases from the combustion process, presents a potential environmental and health problem that is difficult to assess. The goals of the present effort are to estimate the height of the smoke plume, the ground-level concentrations of the toxic pollutants (smoke, SO 2, CO, PAHs, VOCs) and to characterize risk zones by comparing the ground-level concentrations with existing safety limits. For the application of the numerical procedure developed, an external floating-roof tank has been selected with dimensions of 85 m diameter and 20 m height. Results are presented and discussed. It is concluded that for all scenarios considered, the ground-level concentrations of smoke, SO 2, CO, PAHs and VOCs do not exceed the safety limit of IDLH and there are no "death zones" due to the pollutant concentrations.

  11. MODELING OF CHEMICAL TRANSFORMATIONS OF SO(X) AND NO(X) IN THE POLLUTED ATMOSPHERE. AN OVERVIEW OF APPROACHES AND CURRENT STATUS

    EPA Science Inventory

    Two principal approaches are identified in the modeling of chemical transformations of SOx and NOx in the polluted atmosphere. The fundamental approach involves simulation of the detailed chemical kinetics of the SOx-NOx-HC system; in the empirical approach, relatively simple par...

  12. Upper atmosphere pollution measurements (GASP)

    NASA Technical Reports Server (NTRS)

    Rudey, R. A.; Holdeman, J. D.

    1975-01-01

    The environmental effects are discussed of engine effluents of future large fleets of aircraft operating in the stratosphere. Topics discussed include: atmospheric properties, aircraft engine effluents, upper atmospheric measurements, global air sampling, and data reduction and analysis

  13. Advection fog formation in a polluted atmosphere

    SciTech Connect

    Hung, R.J.; Liaw, G.S.

    1981-01-01

    Large quantities of atmospheric aerosols with composition SO/sub 4//sup 2 -/, NO/sub 3//sup -/ and NH/sub 4//sup +/ have been detected in highly industrialized areas. The major portions of aerosol products are the results of energy related fuel combustion. Both microphysical and macrophysical processes are considered in investigating the time dependent evolution of the saturation spectra of condensation nuclei associated with both polluted and clean atmospheres during the time periods of advection fog formation. The results show that the condensation nuclei associated with a polluted atmosphere provide more favorable conditions than condensation nuclei associated with a clean atmosphere to produce dense advection fog, and that attaining a certain degree of supersaturation is not necessarily required for the formation of advection fog with condensation nuclei associated with a polluted atmosphere for monodisperse distribution.

  14. Regional transport and dilution during high-pollution episodes in southern France: Summary of findings from the Field Experiment to Constraint Models of Atmospheric Pollution and Emissions Transport (ESCOMPTE)

    NASA Astrophysics Data System (ADS)

    Drobinski, P.; SaïD, F.; Ancellet, G.; Arteta, J.; Augustin, P.; Bastin, S.; Brut, A.; Caccia, J. L.; Campistron, B.; Cautenet, S.; Colette, A.; Coll, I.; Corsmeier, U.; Cros, B.; Dabas, A.; Delbarre, H.; Dufour, A.; Durand, P.; GuéNard, V.; Hasel, M.; Kalthoff, N.; Kottmeier, C.; Lasry, F.; Lemonsu, A.; Lohou, F.; Masson, V.; Menut, L.; Moppert, C.; Peuch, V. H.; Puygrenier, V.; Reitebuch, O.; Vautard, R.

    2007-07-01

    In the French Mediterranean basin the large city of Marseille and its industrialized suburbs (oil plants in the Fos-Berre area) are major pollutant sources that cause frequent and hazardous pollution episodes, especially in summer when intense solar heating enhances the photochemical activity and when the sea breeze circulation redistributes pollutants farther north in the countryside. This paper summarizes the findings of 5 years of research on the sea breeze in southern France and related mesoscale transport and dilution of pollutants within the Field Experiment to Constraint Models of Atmospheric Pollution and Emissions Transport (ESCOMPTE) program held in June and July 2001. This paper provides an overview of the experimental and numerical challenges identified before the ESCOMPTE field experiment and summarizes the key findings made in observation, simulation, and theory. We specifically address the role of large-scale atmospheric circulation to local ozone vertical distribution and the mesoscale processes driving horizontal advection of pollutants and vertical transport and mixing via entrainment at the top of the sea breeze or at the front and venting along the sloped terrain. The crucial importance of the interactions between processes of various spatial and temporal scales is thus highlighted. The advances in numerical modeling and forecasting of sea breeze events and ozone pollution episodes in southern France are also underlined. Finally, we conclude and point out some open research questions needing further investigation.

  15. Modelling the impact of climate change on the atmospheric transport and the fate of persistent organic pollutants in the Arctic

    NASA Astrophysics Data System (ADS)

    Hansen, K. M.; Christensen, J. H.; Geels, C.; Silver, J. D.; Brandt, J.

    2015-06-01

    The Danish Eulerian Hemispheric Model (DEHM) was applied to investigate how projected climate changes will affect the atmospheric transport of 13 persistent organic pollutants (POPs) to the Arctic and their environmental fate within the Arctic. Three sets of simulations were performed, one with present day emissions and initial environmental concentrations from a 20-year spin-up simulation, one with present day emissions and with initial environmental concentrations set to zero and one without emissions but with initial environmental concentrations from the 20-year spin-up simulation. Each set of simulations consisted of two 10-year time slices representing the present (1990-2000) and future (2090-2100) climate conditions. DEHM was driven using meteorological input from the global circulation model, ECHAM/MPI-OM, simulating the SRES (Special Report on Emissions Scenarios) A1B climate scenario. Under the applied climate and emission scenarios, the total mass of all compounds was predicted to be up to 55 % lower across the Northern Hemisphere at the end of the 2090s than in the 1990s. The mass of HCHs within the Arctic was predicted to be up to 38 % higher, whereas the change in mass of the PCBs was predicted to range from 38 % lower to 17 % higher depending on the congener and the applied initial environmental concentrations. The results of this study also indicate that contaminants with no or a short emission history will be more rapidly transported to and build up in the arctic environment in a future warmer climate. The process that dominates the environmental behaviour of POPs in the Arctic under a future warmer climate scenario is the shift in mass of POPs from the surface media to the atmosphere induced by the higher mean temperature. This is to some degree counteracted by higher degradation rates also following the higher mean temperature. The more dominant of these two processes depends on the physical-chemical properties of the compounds. Previous model

  16. Modelling impact of climate change on atmospheric transport and fate of persistent organic pollutants in the Arctic

    NASA Astrophysics Data System (ADS)

    Hansen, K. M.; Christensen, J. H.; Geels, C.; Silver, J. D.; Brandt, J.

    2015-03-01

    The Danish Eulerian Hemispheric Model (DEHM) was applied to investigate how projected climate changes will affect the atmospheric transport of 13 persistent organic pollutants (POPs) to the Artic and their environmental fate within the Arctic. Two sets of simulations were performed, one with initial environmental concentrations from a 20 year spin-up simulation and one with initial environmental concentrations set to zero. Each set of simulations consisted of two ten-year time slices representing the present (1990-2000) and future (2090-2100) climate conditions. The same POP emissions were applied in all simulations to ensure that the difference in predicted concentrations for each set of simulations only arises from the difference in climate input. DEHM was driven using meteorological input from the global circulation model, ECHAM/MPI-OM, simulating the SRES A1B climate scenario. Under the applied climate and emission scenarios, the total mass of all compounds was predicted to be up to 20% higher across the Northern Hemisphere. The mass of HCHs within the Arctic was predicted to be up to 39% higher, whereas the change in mass of the PCBs was predicted to range from 14% lower to 17% higher depending on the congener and the applied initial environmental concentrations. The results of this study also indicate that contaminants with no or a short emission history will be more rapidly transported to and build up in the arctic environment in a future warmer climate. The process that dominates the environmental behaviour of POPs in the Arctic under a future warmer climate scenario is the shift in mass of POPs from the surface media to the atmosphere induced by the higher mean temperature. This is to some degree counteracted by higher degradation rates also following the higher mean temperature. The more dominant of these two processes depend on the physical-chemical properties of the compounds. Previous model studies have predicted that the effect of a changed climate on

  17. Application of computational fluid mechanics to atmospheric pollution problems

    NASA Technical Reports Server (NTRS)

    Hung, R. J.; Liaw, G. S.; Smith, R. E.

    1986-01-01

    One of the most noticeable effects of air pollution on the properties of the atmosphere is the reduction in visibility. This paper reports the results of investigations of the fluid dynamical and microphysical processes involved in the formation of advection fog on aerosols from combustion-related pollutants, as condensation nuclei. The effects of a polydisperse aerosol distribution, on the condensation/nucleation processes which cause the reduction in visibility are studied. This study demonstrates how computational fluid mechanics and heat transfer modeling can be applied to simulate the life cycle of the atmosphereic pollution problems.

  18. Atmospheric pollutants and trace gases

    SciTech Connect

    Ranieri, A.; Schenone, G.; Lencioni, L.; Soldatini, G.F.

    1994-03-01

    Pumpkin [Cucurbita pepo (L.) cv. Ambassador] plants were grown under either nonfiltered or filtered ambient air in open-top field chambers (OTCs) near the urban area of Milan, Northern Italy. The effects of ambient air pollution on the enzymatic detoxfication system of the leaves, both in terms of activity and isoform pattern were investigated. The data on air quality showed that ozone was the main phytotoxic pollutant present in ambient air, reaching a 7 h mean of 63 nL L{sup -1} and a maximum hourly peak of 104 nL L{sup -1} The peroxidase and catalase activities increased fourfold and twofold, respectively in the nonfiltered air plants In comparison to the filtered air ones. The peroxidase patterns were very modified in the polluted plants. In contrast no significant changes were found in the activity and isoenzyme pattern of superoxide dismutase. The data reported here suggest that in field-grown pumpkin plants exposed to ambient levels of photooxidants, a stimulation of the peroxddase-catalase detoxification system takes place. 32 refs., 3 figs., 3 tabs.

  19. A mathematical model, algorithm, and package of programs for simulation and prompt estimation of the atmospheric dispersion of radioactive pollutants

    SciTech Connect

    Nikolaev, V.I.; Yatsko, S.N.

    1995-12-01

    A mathematical model and a package of programs are presented for simulating the atmospheric turbulent diffusion of contaminating impurities from land based and other sources. Test calculations and investigations of the effect of various factors are carried out.

  20. Source apportionment of gaseous atmospheric pollutants by means of an absolute principal component scores (APCS) receptor model.

    PubMed

    Bruno, P; Caselli, M; de Gennaro, G; Traini, A

    2001-12-01

    A multivariate statistical method has been applied to apportion the atmospheric pollutant concentrations measured by automatic gas analyzers placed on a mobile laboratory for air quality monitoring in Taranto (Italy). In particular, Principal Component Analysis (PCA) followed by Absolute Principal Component Scores (APCS) technique was performed to identify the number of emission sources and their contribution to measured concentrations of CO, NOx, benzene toluene m+p-Xylene (BTX). This procedure singled out two different sources that explain about 85% of collected data variance. PMID:11798109

  1. Does toxicity of aromatic pollutants increase under remote atmospheric conditions?

    NASA Astrophysics Data System (ADS)

    Kroflič, Ana; Grilc, Miha; Grgić, Irena

    2015-03-01

    Aromatic compounds contribute significantly to the budget of atmospheric pollutants and represent considerable hazard to living organisms. However, they are only rarely included into atmospheric models which deviate substantially from field measurements. A powerful experimental-simulation tool for the assessment of the impact of low- and semi-volatile aromatic pollutants on the environment due to their atmospheric aqueous phase aging has been developed and introduced for the first time. The case study herein reveals that remote biotopes might be the most damaged by wet urban guaiacol-containing biomass burning aerosols. It is shown that only after the primary pollutant guaiacol has been consumed, its probably most toxic nitroaromatic product is largely formed. Revising the recent understanding of atmospheric aqueous phase chemistry, which is mostly concerned with the radical nitration mechanisms, the observed phenomenon is mainly attributed to the electrophilic nitrogen-containing reactive species. Here, their intriguing role is closely inspected and discussed from the ecological perspective.

  2. Does toxicity of aromatic pollutants increase under remote atmospheric conditions?

    PubMed Central

    Kroflič, Ana; Grilc, Miha; Grgić, Irena

    2015-01-01

    Aromatic compounds contribute significantly to the budget of atmospheric pollutants and represent considerable hazard to living organisms. However, they are only rarely included into atmospheric models which deviate substantially from field measurements. A powerful experimental-simulation tool for the assessment of the impact of low- and semi-volatile aromatic pollutants on the environment due to their atmospheric aqueous phase aging has been developed and introduced for the first time. The case study herein reveals that remote biotopes might be the most damaged by wet urban guaiacol-containing biomass burning aerosols. It is shown that only after the primary pollutant guaiacol has been consumed, its probably most toxic nitroaromatic product is largely formed. Revising the recent understanding of atmospheric aqueous phase chemistry, which is mostly concerned with the radical nitration mechanisms, the observed phenomenon is mainly attributed to the electrophilic nitrogen-containing reactive species. Here, their intriguing role is closely inspected and discussed from the ecological perspective. PMID:25748923

  3. Atmospheric Pollution: Its Origins and Prevention.

    ERIC Educational Resources Information Center

    Meetham, A. R.

    Although atmospheric pollution can be reduced or eliminated in many different ways, each way involves questions of economics, the time factor, availability of materials, priority over other urgent reforms, and individual and social psychology. To provide a basis for consideration of these questions, this book gives information not only about the…

  4. Clean Air Slots Amid Atmospheric Pollution

    NASA Technical Reports Server (NTRS)

    Hobbs, Peter V.

    2002-01-01

    Layering in the Earth's atmosphere is most commonly seen where parts of the atmosphere resist the incursion of air parcels from above and below - for example, when there is an increase in temperature with height over a particular altitude range. Pollutants tend to accumulate underneath the resulting stable layers. which is why visibility often increases markedly above certain altitudes. Here we describe the occurrence of an opposite effect, in which stable layers generate a layer of remarkably clean air (we refer to these layers as clean-air 'slots') sandwiched between layers of polluted air. We have observed clean-air slots in various locations around the world, but they are particularly well defined and prevalent in southern Africa during the dry season August-September). This is because at this time in this region, stable layers are common and pollution from biomass burning is widespread.

  5. Atmospheric dispersion modeling with AERMOD for comparative impact assessment of different pollutant emission sources in an Alpine context

    NASA Astrophysics Data System (ADS)

    Antonacci, Gianluca; Giovannini, Lorenzo; Tomasi, Elena; Zardi, Dino

    2015-04-01

    High-resolution simulations are performed with the AERMOD model to analyze the impact on air quality of different pollutant emission sources in the area surrounding the town of Vipiteno in the northeastern Italian Alps. In this area the environmental burden of pollutant emissions is particularly high because of both its complex terrain and the presence of specific pollutant sources. In this study the effects of the main sources are analyzed and compared: the A22 motorway, which leads to the Brenner pass, the town of Vipiteno, mainly characterized by intensive use of biomass for house heating, three major plants with high emission rates, and a parking lot located near the motorway, offering park spaces for up to 260 trucks and 50 cars. To assess the impact of these pollution sources the AERMOD model is run with a spatial resolution of 25 m and with meteorological input data obtained from different datasets, such as annual series of standard meteorological variables taken from local weather stations and a set of vertical soundings. During the simulations the sources are modeled in different ways depending on the type of the emissions: the motorway is modeled as a linear source, the village as a diffuse source, the local companies as point sources and the parking lot is modeled as a composition of a diffuse source, representing the idling vehicles inside the park, and of a linear source, representing the access routes to the parking. For each type of source, specific emission factors are chosen, and hourly and seasonal emission patterns are set with particular attention to the analysis of idling vehicle emission factors. The results of the simulations are analyzed in terms of NO2 and PM10 and the impact of each source is discussed.

  6. Some Observational and Modeling Studies of the Atmospheric Boundary Layer at Mississippi Gulf Coast for Air Pollution Dispersion Assessment

    PubMed Central

    Yerramilli, Anjaneyulu; Challa, Venkata Srinivas; Indracanti, Jayakumar; Dasari, Hariprasad; Baham, Julius; Patrick, Chuck; Young, John; Hughes, Robert; White, Lorren D.; Hardy, Mark G.; Swanier, Shelton

    2008-01-01

    Coastal atmospheric conditions widely vary from those over inland due to the land-sea interface, temperature contrast and the consequent development of local circulations. In this study a field meteorological experiment was conducted to measure vertical structure of boundary layer during the period 25–29 June, 2007 at three locations Seabee base, Harrison and Wiggins sites in the Mississippi coast. A GPS Sonde along with slow ascent helium balloon and automated weather stations equipped with slow and fast response sensors were used in the experiment. GPS sonde were launched at three specific times (0700 LT, 1300 LT and 1800 LT) during the experiment days. The observations indicate shallow boundary layer near the coast which gradually develops inland. The weather research and forecasting (WRF) meso-scale atmospheric model and a Lagrangian particle dispersion model (HYSPLIT) are used to simulate the lower atmospheric flow and dispersion in a range of 100 km from the coast for 28–30 June, 2007. The simulated meteorological parameters were compared with the experimental observations. The meso-scale model results show significant temporal and spatial variations in the meteorological fields as a result of development of sea breeze flow, its coupling with the large scale flow field and the ensuing alteration in the mixing depth across the coast. Simulated ground-level concentrations of SO2 from four elevated point sources located along the coast indicate diurnal variation and impact of the local sea-land breeze on the direction of the plume. Model concentration levels were highest during the stable morning condition and during the sea-breeze time in the afternoon. The highest concentrations were found up to 40 km inland during sea breeze time. The study illustrates the application of field meteorological observations for the validation of WRF which is coupled to HYSPLIT for dispersion assessment in the coastal region. PMID:19151446

  7. The propagation of light pollution in the atmosphere

    NASA Astrophysics Data System (ADS)

    Cinzano, P.; Falchi, F.

    2012-12-01

    Recent methods to map artificial night-sky brightness and stellar visibility across large territories or their distribution over the entire sky at any site are based on computation of the propagation of light pollution with Garstang models, a simplified solution of the radiative transfer problem in the atmosphere that allows fast computation by reducing it to a ray-tracing approach. They are accurate for a clear atmosphere, when a two-scattering approximation is acceptable, which is the most common situation. We present here up-to-date extended Garstang models (EGM), which provide a more general numerical solution for the radiative transfer problem applied to the propagation of light pollution in the atmosphere. We also present the LPTRAN software package, an application of EGM to high-resolution Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS) satellite measurements of artificial light emission and to GTOPO30 (Global 30 Arcsecond) digital elevation data, which provides an up-to-date method to predict the artificial brightness distribution of the night sky at any site in the world at any visible wavelength for a broad range of atmospheric situations and the artificial radiation density in the atmosphere across the territory. EGM account for (i) multiple scattering, (ii) wavelengths from 250 nm to infrared, (iii) the Earth's curvature and its screening effects, (iv) site and source elevation, (v) many kinds of atmosphere with the possibility of custom set-up (e.g. including thermal inversion layers), (vi) a mix of different boundary-layer aerosols and tropospheric aerosols, with the possibility of custom set-up, (vii) up to five aerosol layers in the upper atmosphere, including fresh and aged volcanic dust and meteoric dust, (viii) variations of the scattering phase function with elevation, (ix) continuum and line gas absorption from many species, ozone included, (x) up to five cloud layers, (xi) wavelength-dependent bidirectional

  8. Modelling two-way interactions between atmospheric pollution and weather using high-resolution GEM-MACH

    NASA Astrophysics Data System (ADS)

    Makar, Paul; Gong, Wanmin; Pabla, Balbir; Cheung, Philip; Milbrandt, Jason; Gravel, Sylvie; Moran, Michael; Gilbert, Samuel; Zhang, Junhua; Zheng, Qiong

    2013-04-01

    set of optical properties for extinction, single scattering albedo, and asymmetry factor. Ozone in GEM is taken from a default 2D (latitude-height) monthly climatology. We have replaced the ozone below the model top with the ozone calculated from GEM-MACH's chemistry, and the default optical parameters associated with particulate matter have been replaced by those calculated with a Mie scattering algorithm. These changes were found to have a significant local impact on both weather and air-quality predictions for short-term test runs of 24 hours duration. In that particular case, the maximum number concentration of cloud droplets decreased by an order of magnitude, while the number of raindrops increased by an order of magnitude and changed in spatial distribution, but surface rainfall was found to decrease. The differences in meteorology had a profound effect on local pollutant plume concentrations at specific locations and times. We compare results over a longer time period, using two parallel forecast systems, one with feedbacks between meteorology and chemistry, one without. Both nest GEM-MACH from a North American domain (10 km horizontal grid spacing) to a 1535 x 1360 km, 2.5 km domain. These systems will be evaluated against monitoring networks within the high resolution domain.

  9. Air pollution modeling and its application III

    SciTech Connect

    De Wispelaere, C.

    1984-01-01

    This book focuses on the Lagrangian modeling of air pollution. Modeling cooling tower and power plant plumes, modeling the dispersion of heavy gases, remote sensing as a tool for air pollution modeling, dispersion modeling including photochemistry, and the evaluation of model performances in practical applications are discussed. Specific topics considered include dispersion in the convective boundary layer, the application of personal computers to Lagrangian modeling, the dynamic interaction of cooling tower and stack plumes, the diffusion of heavy gases, correlation spectrometry as a tool for mesoscale air pollution modeling, Doppler acoustic sounding, tetroon flights, photochemical air quality simulation modeling, acid deposition of photochemical oxidation products, atmospheric diffusion modeling, applications of an integral plume rise model, and the estimation of diffuse hydrocarbon leakages from petrochemical factories. This volume constitutes the proceedings of the Thirteenth International Technical Meeting on Air Pollution Modeling and Its Application held in France in 1982.

  10. MEASUREMENT AND MODELING OF ATMOSPHERIC MERCURY SPECIES AND RELATED POLLUTANTS IN SOUTH FLORIDA FROM 2000-2005

    EPA Science Inventory

    In 2000, Florida DEP, USEPA, and Broward EPD located an atmospheric mercury monitoring site adjacent to the Everglades in southeast Florida for the purposes of field testing the Tekran mercury speciation system under long-term operational conditions and evaluating the impact of e...

  11. Frontiers in Atmospheric Chemistry Modelling

    NASA Astrophysics Data System (ADS)

    Colette, Augustin; Bessagnet, Bertrand; Meleux, Frederik; Rouïl, Laurence

    2013-04-01

    The first pan-European kilometre-scale atmospheric chemistry simulation is introduced. The continental-scale air pollution episode of January 2009 is modelled with the CHIMERE offline chemistry-transport model with a massive grid of 2 million horizontal points, performed on 2000 CPU of a high performance computing system hosted by the Research and Technology Computing Center at the French Alternative Energies and Atomic Energy Commission (CCRT/CEA). Besides the technical challenge, which demonstrated the robustness of the selected air quality model, we discuss the added value in terms of air pollution modelling and decision support. The comparison with in-situ observations shows that model biases are significantly improved despite some spurious added spatial variability attributed to shortcomings in the emission downscaling process and coarse resolution of the meteorological fields. The increased spatial resolution is clearly beneficial for the detection of exceedances and exposure modelling. We reveal small scale air pollution patterns that highlight the contribution of city plumes to background air pollution levels. Up to a factor 5 underestimation of the fraction of population exposed to detrimental levels of pollution can be obtained with a coarse simulation if subgrid scale correction such as urban increments are ignored. This experiment opens new perspectives for environmental decision making. After two decades of efforts to reduce air pollutant emissions across Europe, the challenge is now to find the optimal trade-off between national and local air quality management strategies. While the first approach is based on sectoral strategies and energy policies, the later builds upon new alternatives such as urban development. The strategies, the decision pathways and the involvement of individual citizen differ, and a compromise based on cost and efficiency must be found. We illustrated how high performance computing in atmospheric science can contribute to this

  12. Impact of pollution controls in Beijing on atmospheric oxygenated volatile organic compounds (OVOCs) during the 2008 Olympic Games: observation and modeling implications

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Yuan, B.; Li, X.; Shao, M.; Lu, S.; Li, Y.; Chang, C.-C.; Zhu, T.

    2014-10-01

    Oxygenated volatile organic compounds (OVOCs) are important products of the photo-oxidation of hydrocarbons. They influence the oxidizing capacity and the ozone forming potential of the atmosphere. In the summer of 2008 two months' emission restrictions were enforced in Beijing to improve air quality during the Olympic Games. Observation evidence has been reported in related studies that these control measures were efficient in reducing the concentrations of primary anthropogenic pollutants (CO, NOx and non-methane hydrocarbons, i.e. NMHCs) by 30-40%. In this study, the influence of the emission restrictions on ambient levels of OVOCs was explored using a neural network analysis with consideration of meteorological conditions. Statistically significant reductions in formaldehyde (HCHO), acetaldehyde (CH3CHO), methyl ethyl ketone (MEK) and methanol were found to be 12.9, 15.8, 17.1 and 19.6%, respectively, when the restrictions were in place. The effect of emission control on acetone was not detected in neural network simulations, probably due to pollution transport from surrounding areas outside Beijing. Although the ambient levels of most NMHCs were decreased by ~35% during the full control period, the emission ratios of reactive hydrocarbons attributed to vehicular emissions did not present obvious difference. A zero-dimensional box model based on Master Chemical Mechanism version 3.2 (MCM3.2) was applied to evaluate how OVOCs productions respond to the reduced precursors during the emission controlled period. On average, secondary HCHO was produced from the oxidation of anthropogenic alkenes (54%), isoprene (30%) and aromatics (15%). The importance of biogenic source for the total HCHO formation was almost on a par with that of anthropogenic alkenes during the daytime. Anthropogenic alkenes and alkanes dominated the photochemical production of other OVOCs such as acetaldehyde, acetone and MEK. The relative changes of modelled aldehydes, methyl vinyl ketone and

  13. Impact of pollution controls in Beijing on atmospheric oxygenated volatile organic compounds (OVOCs) during the 2008 Olympic Games: observation and modeling implications

    NASA Astrophysics Data System (ADS)

    Liu, Y.; Yuan, B.; Li, X.; Shao, M.; Lu, S.; Li, Y.; Chang, C.-C.; Wang, Z.; Hu, W.; Huang, X.; He, L.; Zeng, L.; Hu, M.; Zhu, T.

    2015-03-01

    Oxygenated volatile organic compounds (OVOCs) are important products of the photo-oxidation of hydrocarbons. They influence the oxidizing capacity and the ozone-forming potential of the atmosphere. In the summer of 2008, 2 months of emission restrictions were enforced in Beijing to improve air quality during the Olympic Games. Observational evidence reported in related studies that these control measures were efficient in reducing the concentrations of primary anthropogenic pollutants (CO, NOx and non-methane hydrocarbons, i.e., NMHCs) by 30-40%. In this study, the influence of the emission restrictions on ambient levels of OVOCs was explored using a neural network analysis with consideration of meteorological conditions. Statistically significant reductions in formaldehyde (HCHO), acetaldehyde (CH3CHO), methyl ethyl ketone (MEK) and methanol were found to be 12.9, 15.8, 17.1 and 19.6%, respectively, when the restrictions were in place. The effect of emission controls on acetone was not detected in neural network simulations, probably due to pollution transport from surrounding areas outside Beijing. Although the ambient levels of most NMHCs were reduced by ~35% during the full control period, the emission ratios of reactive alkenes and aromatics closely related to automobile sources did not present much difference (< 30%). A zero-dimensional box model based on the Master Chemical Mechanism version 3.2 (MCM3.2) was applied to evaluate how OVOC production responds to the reduced precursors during the emissions control period. On average, secondary HCHO was produced from the oxidation of anthropogenic alkenes (54%), isoprene (30%) and aromatics (15%). The importance of biogenic sources for the total HCHO formation was almost on par with that of anthropogenic alkenes during the daytime. Anthropogenic alkenes and alkanes dominated the photochemical production of other OVOCs such as acetaldehyde, acetone and MEK. The relative changes of modeled HCHO, CH3CHO, methyl

  14. Hybrid regional air pollution models

    SciTech Connect

    Drake, R.L.

    1980-03-01

    This discussion deals with a family of air quality models for predicting and analyzing the fine particulate loading in the atmosphere, for assessing the extent and degree of visibility impairment, and for determining the potential of pollutants for increasing the acidity of soils and water. The major horizontal scales of interest are from 400km to 2000km; and the time scales may vary from several hours, to days, weeks, and a few months or years, depending on the EPA regulations being addressed. First the role air quality models play in the general family of atmospheric simulation models is described. Then, the characteristics of a well-designed, comprehensive air quality model are discussed. Following this, the specific objectives of this workshop are outlined, and their modeling implications are summarized. There are significant modeling differences produced by the choice of the coordinate system, whether it be the fixed Eulerian system, the moving Lagrangian system, or some hybrid of the two. These three systems are briefly discussed, and a list of hybrid models that are currently in use are given. Finally, the PNL regional transport model is outlined and a number of research needs are listed.

  15. Atmospheric pollutant outflow from southern Asia: a review

    NASA Astrophysics Data System (ADS)

    Lawrence, M. G.; Lelieveld, J.

    2010-11-01

    Southern Asia, extending from Pakistan and Afghanistan to Indonesia and Papua New Guinea, is one of the most heavily populated regions of the world. Biofuel and biomass burning play a disproportionately large role in the emissions of most key pollutant gases and aerosols there, in contrast to much of the rest of the Northern Hemisphere, where fossil fuel burning and industrial processes tend to dominate. This results in polluted air masses which are enriched in carbon-containing aerosols, carbon monoxide, and hydrocarbons. The outflow and long-distance transport of these polluted air masses is characterized by three distinct seasonal circulation patterns: the winter monsoon, the summer monsoon, and the monsoon transition periods. During winter, the near-surface flow is mostly northeasterly, and the regional pollution forms a thick haze layer in the lower troposphere which spreads out over millions of square km between southern Asia and the Intertropical Convergence Zone (ITCZ), located several degrees south of the equator over the Indian Ocean during this period. During summer, the heavy monsoon rains effectively remove soluble gases and aerosols. Less soluble species, on the other hand, are lifted to the upper troposphere in deep convective clouds, and are then transported away from the region by strong upper tropospheric winds, particularly towards northern Africa and the Mediterranean in the tropical easterly jet. Part of the pollution can reach the tropical tropopause layer, the gateway to the stratosphere. During the monsoon transition periods, the flow across the Indian Ocean is primarily zonal, and strong pollution plumes originating from both southeastern Asia and from Africa spread across the central Indian Ocean. This paper provides a review of the current state of knowledge based on the many observational and modeling studies over the last decades that have examined the southern Asian atmospheric pollutant outflow and its large scale effects. An outlook

  16. Laboratory studies of sources of HONO in polluted urban atmospheres

    NASA Astrophysics Data System (ADS)

    Saliba, Najat A.; Mochida, Michihiro; Finlayson-Pitts, Barbara. J.

    2000-10-01

    Laboratory studies reported here and in previous work show that the reaction of NO(g) with surface adsorbed HNO3 may be a significant source of HONO in polluted urban atmospheres. If these laboratory studies can be extrapolated to ambient conditions, this heterogeneous reaction may generate HONO to about the same extent as the hydrolysis of NO2 on surfaces, which is greater than the heterogeneous reaction of NO, NO2 and water. It may also be involved in generating HONO in snowpacks, and important in reconciling the discrepancy between measured and modeled HNO3/NOx ratios in the troposphere.

  17. Global Atmospheric Aerosol Modeling

    NASA Technical Reports Server (NTRS)

    Hendricks, Johannes; Aquila, Valentina; Righi, Mattia

    2012-01-01

    Global aerosol models are used to study the distribution and properties of atmospheric aerosol particles as well as their effects on clouds, atmospheric chemistry, radiation, and climate. The present article provides an overview of the basic concepts of global atmospheric aerosol modeling and shows some examples from a global aerosol simulation. Particular emphasis is placed on the simulation of aerosol particles and their effects within global climate models.

  18. Community Atmosphere Model

    Energy Science and Technology Software Center (ESTSC)

    2004-10-18

    The Community Atmosphere Model (CAM) is an atmospheric general circulation model that solves equations for atmospheric dynamics and physics. CAM is an outgrowth of the Community Climate Model at the National Center for Atmospheric Research (NCAR) and was developed as a joint collaborative effort between NCAR and several DOE laboratories, including LLNL. CAM contains several alternative approaches for advancing the atmospheric dynamics. One of these approaches uses a finite-volume method originally developed by personnel atmore » NASNGSFC, We have developed a scalable version of the finite-volume solver for massively parallel computing systems. FV-CAM is meant to be used in conjunction with the Community Atmosphere Model. It is not stand-alone.« less

  19. Infrared differential absorption for atmospheric pollutant detection

    NASA Technical Reports Server (NTRS)

    Byer, R. L.

    1974-01-01

    Progress made in the generation of tunable infrared radiation and its application to remote pollutant detection by the differential absorption method are summarized. It is recognized that future remote pollutant measurements depended critically on the availability of high energy tunable transmitters. Futhermore, due to eye safety requirements, the transmitted frequency must lie in the 1.4 micron to 13 micron infrared spectral range.

  20. Nonisothermal Pluto atmosphere models

    SciTech Connect

    Hubbard, W.B.; Yelle, R.V.; Lunine, J.I. )

    1990-03-01

    The present thermal profile calculation for a Pluto atmosphere model characterized by a high number fraction of CH4 molecules encompasses atmospheric heating by solar UV flux absorption and conductive transport cooling to the surface of Pluto. The stellar occultation curve predicted for an atmosphere of several-microbar surface pressures (which entail the existence of a substantial temperature gradient close to the surface) agrees with observations and implies that the normal and tangential optical depth of the atmosphere is almost negligible. The minimum period for atmospheric methane depletion is calculated to be 30 years. 29 refs.

  1. Ideas in Practice: Studies in Atmospheric Pollution For Science Teachers

    ERIC Educational Resources Information Center

    Rowe, Donald R.

    1974-01-01

    Describes the content and structure of an enviromental course offered by the Department of Engineering Technology at Western Kentucky University. The course focuses on atmospheric pollution and is designed for science teachers currently teaching in the school system. (JR)

  2. Laboratory measurements of Photochemical Properties of Atmospheric Pollutants.

    NASA Astrophysics Data System (ADS)

    Orkin, V. L.

    2012-04-01

    One of the most important parameters in estimating the environmental impact due to emission of a compound is its residence time in the atmosphere, which is driven by the reaction of a compound with hydroxyl radicals (OH) for many atmospheric trace gases. The atmospheric lifetime is important for estimating ozone depletion potential (ODP) and global warming potential (GWP) of industrial compounds which are needed for evaluation of their environmental impact and regulatory purposes. The sources of critically evaluated photochemical data for atmospheric modeling, NASA/JPL Publications and IUPAC Publications, recommend uncertainties within 10%-60% for the majority of OH reaction rate constants with only a few cases where uncertainties lie at the low end of this range. These uncertainties can be somewhat conservative because evaluations are based on the data from various laboratories obtained during the last few decades. Nevertheless, even the authors of the original experimental works rarely estimate the total combined uncertainties of the published OH reaction rate constants to be less than ca. 10%. Thus, uncertainties in the photochemical properties of potential and current atmospheric trace gases obtained under controlled laboratory conditions still constitute a major source of uncertainty in estimating the compound's environmental impact. One of the purposes of the present work was to illustrate the potential for obtaining accurate laboratory measurements of the OH reaction rate constant over the temperature range of atmospheric interest. We provide a detailed inventory of accountable sources of instrumental uncertainties related to our FP-RF experiment to prove a total uncertainty of the OH reaction rate constant to be ca. 2%. The results of accurate measurements of photochemical properties of industrial and natural atmospheric pollutants will be presented.

  3. ATMOSPHERIC TURBULENCE AND POLLUTANT DISPERSION NEAR ROADWAYS

    EPA Science Inventory

    The major objectives of this investigation are: (1) to determine the time and space scales of the eddies generated by the traffic, (2) to study the effects of traffic-induced turbulence on the near-field dispersion of pollutants, (3) to evaluate several commonly used highway air ...

  4. Medical aspects of atmosphere pollution in Tbilisi, Georgia.

    PubMed

    Lagidze, Lamzira; Matchavariani, Lia; Tsivtsivadze, Nodar; Khidasheli, Nargiz; Paichadze, Nino; Motsonelidze, Nargiz; Vakhtangishvili, Maia

    2015-01-01

    Climate change and its impact on ecosystems is one of the main problem of 21st century. Increase in green house gas in the atmosphere was regarded as an important cause. Atmospheric composition had significantly changed due to intensive technogenic pollution. Increase in aerosol (solid, liquid and gas) concentration had serious impact on human health and raised the level of risk factors for longevity of life. Despite, global character of climatic change and its intensity in numerous ways was influenced by local specificity of regions, their geographical location and meteorological factors. A study on the atmospheric quality (quantitative and percentage estimation of aerosols) of Georgia was carried out. Also the assessment of impact of meteorological and ecological conditions on human health was made for Tbilisi city. A relation between contaminants and meteorological factors was evaluated, particularly gas pollutants were strongly correlated with each other due to their photochemical activity; positive correlation (0.65; 0.69) between air temperature and pollutants. All the contaminants showed negative correlation with relative humidity, due to hydrolyzing ability. On the basis of multi-factorial statistical analysis, correlation between ambulance call, weather type, atmosphere pollution index, change in ground ozone quantity and earth magnetic field were determined. Atmospheric pollution due to dust, carbon, sulfur and nitrogen oxides, ground ozone quantity in Tbilisi significantly exceeded maximum permissible level, that effected human health. PMID:26591888

  5. Study of organic pollutants oxidation by atmospheric plasma discharge

    NASA Astrophysics Data System (ADS)

    Gumuchian, Diane; Cavadias, Simeon; Duten, Xavier; Tatoulian, Michael; da Costa, Patrick; Ognier, Stephanie

    2013-09-01

    Ozonation is one of the usual steps in water treatment processes. However, some organic molecules (acetic acid) cannot be decomposed during ozonation. In that context, we are developing an Advanced Oxidation Process based on the use of a needle plate discharge at atmospheric pressure. The process is a reactor with a plasma discharge between a high voltage electrode and the solution in controlled atmosphere. Characterizations of the plasma obtained in different atmospheres were carried out (Optical Emission Spectroscopy, iCCD camera observations, etc). The efficiency of the process was evaluated by the percentage of degradation of the model-pollutant, measured by liquid chromatography analysis. Treatments in nitrogen lead to the formation of NOx species that decrease the efficiency of the process. Indeed, NOx lead to the consumption of actives species created. Treatments in argon are the most efficient. Two hypotheses are considered: (i) metastable argon participates to the degradation of acetic acid or to the formation of radicals (ii) discharges in argon lead to the formation of many streamers of low energy that increase the interface plasma/solution.

  6. Supplemental mathematical formulations, Atmospheric pathway: The Multimedia Environmental Pollutant Assessment System (MEPAS)

    SciTech Connect

    Droppo, J.G.; Buck, J.W.

    1996-03-01

    The Multimedia Environmental Pollutant Assessment System (MEPAS) is an integrated software implementation of physics-based fate and transport models for health and environmental risk assessments of both radioactive and hazardous pollutants. This atmospheric component report is one of a series of formulation reports that document the MEPAS mathematical models. MEPAS is a ``multimedia`` model; pollutant transport is modeled within, through, and between multiple media (air, soil, groundwater, and surface water). The estimated concentrations in the various media are used to compute exposures and impacts to the environment, to maximum individuals, and to populations.

  7. Modeling atmospheric particle deposition

    NASA Astrophysics Data System (ADS)

    Jackson, Msafiri M.

    Experimentally determined dry deposition velocities for atmospheric particles in the size range of 5-80 μm in diameter have been shown to be greater than predictions made with the current state-of-the-art (Sehmel-Hodgson) model which is based on wind tunnel experiment, particularly at higher wind speed. In this research, a model to predict the atmospheric dry deposition velocities of particles has been developed that is similar to a model developed for particle deposition in vertical pipes. The model uses a sigmoid curve to correlate nondimensional inertial deposition velocity (Vdi+) with dimensionless particle relaxation time (/tau+) and flow Reynolds number (Re). Vdi+ obtained from data collected in the atmosphere with particle size classifier system and a flat greased plate, Re, and /tau+ for particles between 1 and 100 μm diameter were fit with a sigmoid curve using the least square procedure to obtain coefficients for the sigmoid curve. Deposition velocities data for particles between 0.06 and 4 μm diameter developed by Sehmel-Hodgson model were used to introduce a Schmidt number (Sc) term to take care of Brownian diffusion. The atmospheric plate deposition velocity model is a function of Vst (Stokes settling velocity), V* (friction velocity), /tau+, Re, and Sc. Model application to 62 atmospheric data set revealed that: generated flux predictions agreed well with atmospheric measurements, and its performance is better than Sehmel-Hodgson model. By comparing the sigmoid curve coefficients developed for vertical pipe data with the coefficients developed for atmospheric data it is concluded that, the two types of deposition are similar when the effects of Re and /tau+ are properly considered. Sensitivity analysis for the model has revealed three distinct regions based on particle size. Of the three physical parameters (/tau+, Re, Sc) in the model, not more than two controls the deposition in any of the identified regions. The plate deposition model which is

  8. Sampling of Atmospheric Precipitation and Deposits for Analysis of Atmospheric Pollution

    PubMed Central

    Skarżyńska, K.; Polkowska, Ż; Namieśnik, J.

    2006-01-01

    This paper reviews techniques and equipment for collecting precipitation samples from the atmosphere (fog and cloud water) and from atmospheric deposits (dew, hoarfrost, and rime) that are suitable for the evaluation of atmospheric pollution. It discusses the storage and preparation of samples for analysis and also presents bibliographic information on the concentration ranges of inorganic and organic compounds in the precipitation and atmospheric deposit samples. PMID:17671615

  9. MODELING TRANSPORT BY CONVECTIVE CLOUDS FOR REGIONAL AIR POLLUTION MODELS

    EPA Science Inventory

    A model is developed to account for regional scale vertical transport of pollutants from the mixed layer to the overlying free troposphere by an ensemble of non-precipitating cumulus convective clouds. The model determines acceptable cloud classes for given atmospheric state repr...

  10. Solar Atmosphere Models

    NASA Astrophysics Data System (ADS)

    Rutten, R. J.

    2002-12-01

    This contribution honoring Kees de Jager's 80th birthday is a review of "one-dimensional" solar atmosphere modeling that followed on the initial "Utrecht Reference Photosphere" of Heintze, Hubenet & de Jager (1964). My starting point is the Bilderberg conference, convened by de Jager in 1967 at the time when NLTE radiative transfer theory became mature. The resulting Bilderberg model was quickly superseded by the HSRA and later by the VAL-FAL sequence of increasingly sophisticated NLTE continuum-fitting models from Harvard. They became the "standard models" of solar atmosphere physics, but Holweger's relatively simple LTE line-fitting model still persists as a favorite of solar abundance determiners. After a brief model inventory I discuss subsequent work on the major modeling issues (coherency, NLTE, dynamics) listed as to-do items by de Jager in 1968. The present conclusion is that one-dimensional modeling recovers Schwarzschild's (1906) finding that the lower solar atmosphere is grosso modo in radiative equilibrium. This is a boon for applications regarding the solar atmosphere as one-dimensional stellar example - but the real sun, including all the intricate phenomena that now constitute the mainstay of solar physics, is vastly more interesting.

  11. GUIDELINE FOR FLUID MODELING OF ATMOSPHERIC DIFFUSION

    EPA Science Inventory

    The fundamental principles for fluid modeling of flow and dispersion of pollutants in the atmospheric boundary layer are reviewed. The usefulness of fluid models are evaluated from both scientific and engineering viewpoints. Because many detailed decisions must be made during the...

  12. Study of atmospheric pollution scavenging. [Annotated bibligraphy

    SciTech Connect

    Williams, A.L.

    1990-08-01

    Atmospheric scavenging research conducted by the Illinois State Water Survey under contract with the Department of Energy has been a significant factor in the historical development of the field of precipitation scavenging. Emphasis of the work during the 1980's became focused on the problem of acid rain problem with the Survey being chosen as the Central Analytical Laboratory for sample analysis of the National Atmospheric Deposition Program National Trends Network (NADP/NTN). The DOE research was responsible for laying the groundwork from the standpoint of sampling and chemical analysis that has now become routine features of NADP/NTN. A significant aspect of the research has been the participation by the Water Survey in the MAP3S precipitation sampling network which is totally supported by DOE, is the longest continuous precipitation sampling network in existence, and maintains an event sampling protocol. The following review consists of a short description of each of the papers appearing in the Study of Atmospheric Scavenging progress reports starting with the Eighteenth Progress Report in 1980 to the Twenty- Third Progress Report in 1989. In addition a listing of the significant publications and interviews associated with the program are given in the bibliography.

  13. Atmospheric prediction model survey

    NASA Technical Reports Server (NTRS)

    Wellck, R. E.

    1976-01-01

    As part of the SEASAT Satellite program of NASA, a survey of representative primitive equation atmospheric prediction models that exist in the world today was written for the Jet Propulsion Laboratory. Seventeen models developed by eleven different operational and research centers throughout the world are included in the survey. The surveys are tutorial in nature describing the features of the various models in a systematic manner.

  14. A Regulation for the Control of Atmospheric Pollution, Amended Version.

    ERIC Educational Resources Information Center

    Puerto Rico Environmental Quality Board, San Juan.

    Nine articles, related to the preservation of the natural quality of the air, and to prevention, elimination and control of atmospheric pollution in the Commonwealth of Puerto Rico, are contained in this document. These articles were written and enacted by the Environmental Quality Board in accordance with Law No. 9, approved June 18, 1970 -…

  15. Modeling of Cometary Atmospheres

    NASA Technical Reports Server (NTRS)

    Gombosi, Tamas

    2004-01-01

    The NASA supported project 'Modeling of Cometary Atmospheres' has been quite successful in broadening our understanding of the cometary environment. We list peer reviewed publications and conference presentation that have been made as a result of studies performed under this project. Following the list we present details of a selection of the results.

  16. Study on wet scavenging of atmospheric pollutants in south Brazil

    NASA Astrophysics Data System (ADS)

    Wiegand, Flavio; Pereira, Felipe Norte; Teixeira, Elba Calesso

    2011-09-01

    The present paper presents the study of in-cloud and below-cloud SO 2 and SO 42-scavenging processes by applying numerical models in the Candiota region, located in the state of Rio Grande do Sul, South Brazil. The BRAMS (Brazilian Regional Atmospheric Modeling System) model was applied to simulate the vertical structure of the clouds, and the B.V.2 (Below-Cloud Beheng Version 2) scavenging model was applied to simulate in-cloud and below-cloud scavenging processes of the pollutants SO 2 and SO 42-. Five events in 2004 were selected for this study and were sampled at the Candiota Airport station. The concentrations of SO 2 and SO 42- sampled in the air and the simulated meteorological parameters of rainfall episodes were used as input data in the B.V.2, which simulates raindrop interactions associated with the scavenging process. Results for the Candiota region showed that in-cloud scavenging processes were more significant than below-cloud scavenging processes for two of the five events studied, with a contribution of approximately 90-100% of SO 2 and SO 42- concentrations in rainwater. A few adjustments to the original version of B.V.2 were made to allow simulation of scavenging processes in several types of clouds, not only cumulus humilis and cumulus congestus.

  17. A Review of the Effects of Major Atmospheric Pollutants on Pollen Grains, Pollen Content, and Allergenicity

    PubMed Central

    Sénéchal, Hélène; Visez, Nicolas; Charpin, Denis; Shahali, Youcef; Peltre, Gabriel; Biolley, Jean-Philippe; Lhuissier, Franck; Couderc, Rémy; Yamada, Ohri; Malrat-Domenge, Audrey; Pham-Thi, Nhân; Poncet, Pascal; Sutra, Jean-Pierre

    2015-01-01

    This review summarizes the available data related to the effects of air pollution on pollen grains from different plant species. Several studies carried out either on in situ harvested pollen or on pollen exposed in different places more or less polluted are presented and discussed. The different experimental procedures used to monitor the impact of pollution on pollen grains and on various produced external or internal subparticles are listed. Physicochemical and biological effects of artificial pollution (gaseous and particulate) on pollen from different plants, in different laboratory conditions, are considered. The effects of polluted pollen grains, subparticles, and derived aeroallergens in animal models, in in vitro cell culture, on healthy human and allergic patients are described. Combined effects of atmospheric pollutants and pollen grains-derived biological material on allergic population are specifically discussed. Within the notion of “polluen,” some methodological biases are underlined and research tracks in this field are proposed. PMID:26819967

  18. Solar flare model atmospheres

    NASA Technical Reports Server (NTRS)

    Hawley, Suzanne L.; Fisher, George H.

    1993-01-01

    Solar flare model atmospheres computed under the assumption of energetic equilibrium in the chromosphere are presented. The models use a static, one-dimensional plane parallel geometry and are designed within a physically self-consistent coronal loop. Assumed flare heating mechanisms include collisions from a flux of non-thermal electrons and x-ray heating of the chromosphere by the corona. The heating by energetic electrons accounts explicitly for variations of the ionized fraction with depth in the atmosphere. X-ray heating of the chromosphere by the corona incorporates a flare loop geometry by approximating distant portions of the loop with a series of point sources, while treating the loop leg closest to the chromospheric footpoint in the plane-parallel approximation. Coronal flare heating leads to increased heat conduction, chromospheric evaporation and subsequent changes in coronal pressure; these effects are included self-consistently in the models. Cooling in the chromosphere is computed in detail for the important optically thick HI, CaII and MgII transitions using the non-LTE prescription in the program MULTI. Hydrogen ionization rates from x-ray photo-ionization and collisional ionization by non-thermal electrons are included explicitly in the rate equations. The models are computed in the 'impulsive' and 'equilibrium' limits, and in a set of intermediate 'evolving' states. The impulsive atmospheres have the density distribution frozen in pre-flare configuration, while the equilibrium models assume the entire atmosphere is in hydrostatic and energetic equilibrium. The evolving atmospheres represent intermediate stages where hydrostatic equilibrium has been established in the chromosphere and corona, but the corona is not yet in energetic equilibrium with the flare heating source. Thus, for example, chromospheric evaporation is still in the process of occurring.

  19. Association between atmospheric pollutants and hospital admissions in Lisbon.

    PubMed

    Cruz, A M J; Sarmento, S; Almeida, S M; Silva, A V; Alves, C; Freitas, M C; Wolterbeek, H

    2015-04-01

    Ambient air pollution is recognised as one of the potential environmental risk factors causing health hazards to the exposed population, demonstrated in numerous previous studies. Several longitudinal, ecological and epidemiological studies have shown associations between outdoor levels of outdoor atmospheric pollutants and adverse health effects, especially associated with respiratory and cardiovascular hospital admissions. The aim of this work is to assess the influence of atmospheric pollutants over the hospital admissions in Lisbon, by Ordinary Least Squares Linear Regression. The pollutants (CO, NO, NO2, SO2, O3, PM10 and PM2.5) were obtained from 13 monitoring stations of the Portuguese Environmental Agency, which provide hourly observations. Hospital admission data were collected from the Central Administration of the Health System and were compiled by age: <15, 15-64, >64 years old. The study period was 2006-2008. Results showed significant positive associations between the following: (1) the pollutants CO, NO, NO2, SO2, PM10 and PM2.5 and circulatory diseases for ages between 15 and 64 years (0.5% hospital admissions (HA) increase with 10 μg m(-3) NO increase) and above 64 years (1.0% stroke admission increase with 10 μg m(-3) NO2 increase); (2) the pollutants CO, NO, NO2, SO2, PM10 and PM2.5 and respiratory diseases for ages below 15 years (up to 1.9% HA increase with 10 μg m(-3) pollutant increase); and (3) the pollutants NO, NO2 and SO2 and respiratory diseases for ages above 64 years (1.3% HA increase with 10 μg m(-3) CO increase). PMID:25471710

  20. Atmospheric Pollution over the Eastern Mediterranean during summer - A Review

    NASA Astrophysics Data System (ADS)

    Dayan, Uri; Ricaud, Philippe; Zbinden, Regina; Dulac, François

    2016-04-01

    The subsiding air aloft induced by global circulation systems affecting the EM and the depth of the Persian Trough, control the spatio-temporal distribution of the boundary layer during summer. The shallow mixed layer and weak zonal flow, leads to poor ventilation rates, inhibiting an efficient dispersion of the pollutants. Several studies pointing at specific local (e.g. ventilation rates) and regional peculiarities (long range transport) enhancing the building up of pollutant concentrations are presented. Tropospheric-ozone concentrations over the EM basin are among the highest over the Northern Hemisphere. The processes controlling its formation (i.e., long range transport from Europe, dynamic subsidence at mid-troposphere, and stratosphere-to-troposphere exchange) are reviewed. Airborne and satellite-borne initiatives have indicated that the concentration values of reactive nitrogen are 2 to 10 times higher than in the hemispheric background troposphere. Models, aircraft measurements, and satellite data, have shown that sulfate has a maximum during spring and summer. The CO seasonal cycle, mainly governed by the concentration of the hydroxyl radical demonstrates high concentrations over winter months and lowest during summer when photochemistry is active. The daily variations in CO concentration are caused by long-range CO transport from European anthropogenic sources. The spatial distribution of methane, derived from satellite identified August as the month with the highest levels over the EM. The results of a comprehensive analysis of atmospheric methane over the EM Basin as part of the ChArMEx program, using satellite data and model simulations is consistent with other previous studies.

  1. Reference and Standard Atmosphere Models

    NASA Technical Reports Server (NTRS)

    Johnson, Dale L.; Roberts, Barry C.; Vaughan, William W.; Parker, Nelson C. (Technical Monitor)

    2002-01-01

    This paper describes the development of standard and reference atmosphere models along with the history of their origin and use since the mid 19th century. The first "Standard Atmospheres" were established by international agreement in the 1920's. Later some countries, notably the United States, also developed and published "Standard Atmospheres". The term "Reference Atmospheres" is used to identify atmosphere models for specific geographical locations. Range Reference Atmosphere Models developed first during the 1960's are examples of these descriptions of the atmosphere. This paper discusses the various models, scopes, applications and limitations relative to use in aerospace industry activities.

  2. Epiphytic lichen diversity on dead and dying conifers under different levels of atmospheric pollution.

    PubMed

    Hauck, Markus

    2005-05-01

    Based on literature data, epiphytic lichen abundance was comparably studied in montane woodlands on healthy versus dead or dying conifers of Europe and North America in areas with different levels of atmospheric pollution. Study sites comprised Picea abies forests in the Harz Mountains and in the northern Alps, Germany, Picea rubens-Abies balsamea forests on Whiteface Mountain, Adirondacks, New York, U.S.A. and Picea engelmannii-Abies lasiocarpa forests in the Salish Mountains, Montana, U.S.A. Detrended correspondence analysis showed that epiphytic lichen vegetation differed more between healthy and dead or dying trees at high- versus low-polluted sites. This is attributed to greater differences in chemical habitat conditions between trees of different vitality in highly polluted areas. Based on these results, a hypothetical model of relative importance of site factors for small-scale variation of epiphytic lichen abundance versus atmospheric pollutant load is discussed. PMID:15701398

  3. Temporal and Spatial Simulation of Atmospheric Pollutant PM2.5 Changes and Risk Assessment of Population Exposure to Pollution Using Optimization Algorithms of the Back Propagation-Artificial Neural Network Model and GIS

    PubMed Central

    Zhang, Ping; Hong, Bo; He, Liang; Cheng, Fei; Zhao, Peng; Wei, Cailiang; Liu, Yunhui

    2015-01-01

    PM2.5 pollution has become of increasing public concern because of its relative importance and sensitivity to population health risks. Accurate predictions of PM2.5 pollution and population exposure risks are crucial to developing effective air pollution control strategies. We simulated and predicted the temporal and spatial changes of PM2.5 concentration and population exposure risks, by coupling optimization algorithms of the Back Propagation-Artificial Neural Network (BP-ANN) model and a geographical information system (GIS) in Xi’an, China, for 2013, 2020, and 2025. Results indicated that PM2.5 concentration was positively correlated with GDP, SO2, and NO2, while it was negatively correlated with population density, average temperature, precipitation, and wind speed. Principal component analysis of the PM2.5 concentration and its influencing factors’ variables extracted four components that accounted for 86.39% of the total variance. Correlation coefficients of the Levenberg-Marquardt (trainlm) and elastic (trainrp) algorithms were more than 0.8, the index of agreement (IA) ranged from 0.541 to 0.863 and from 0.502 to 0.803 by trainrp and trainlm algorithms, respectively; mean bias error (MBE) and Root Mean Square Error (RMSE) indicated that the predicted values were very close to the observed values, and the accuracy of trainlm algorithm was better than the trainrp. Compared to 2013, temporal and spatial variation of PM2.5 concentration and risk of population exposure to pollution decreased in 2020 and 2025. The high-risk areas of population exposure to PM2.5 were mainly distributed in the northern region, where there is downtown traffic, abundant commercial activity, and more exhaust emissions. A moderate risk zone was located in the southern region associated with some industrial pollution sources, and there were mainly low-risk areas in the western and eastern regions, which are predominantly residential and educational areas. PMID:26426030

  4. Temporal and Spatial Simulation of Atmospheric Pollutant PM2.5 Changes and Risk Assessment of Population Exposure to Pollution Using Optimization Algorithms of the Back Propagation-Artificial Neural Network Model and GIS.

    PubMed

    Zhang, Ping; Hong, Bo; He, Liang; Cheng, Fei; Zhao, Peng; Wei, Cailiang; Liu, Yunhui

    2015-10-01

    PM2.5 pollution has become of increasing public concern because of its relative importance and sensitivity to population health risks. Accurate predictions of PM2.5 pollution and population exposure risks are crucial to developing effective air pollution control strategies. We simulated and predicted the temporal and spatial changes of PM2.5 concentration and population exposure risks, by coupling optimization algorithms of the Back Propagation-Artificial Neural Network (BP-ANN) model and a geographical information system (GIS) in Xi'an, China, for 2013, 2020, and 2025. Results indicated that PM2.5 concentration was positively correlated with GDP, SO₂, and NO₂, while it was negatively correlated with population density, average temperature, precipitation, and wind speed. Principal component analysis of the PM2.5 concentration and its influencing factors' variables extracted four components that accounted for 86.39% of the total variance. Correlation coefficients of the Levenberg-Marquardt (trainlm) and elastic (trainrp) algorithms were more than 0.8, the index of agreement (IA) ranged from 0.541 to 0.863 and from 0.502 to 0.803 by trainrp and trainlm algorithms, respectively; mean bias error (MBE) and Root Mean Square Error (RMSE) indicated that the predicted values were very close to the observed values, and the accuracy of trainlm algorithm was better than the trainrp. Compared to 2013, temporal and spatial variation of PM2.5 concentration and risk of population exposure to pollution decreased in 2020 and 2025. The high-risk areas of population exposure to PM2.5 were mainly distributed in the northern region, where there is downtown traffic, abundant commercial activity, and more exhaust emissions. A moderate risk zone was located in the southern region associated with some industrial pollution sources, and there were mainly low-risk areas in the western and eastern regions, which are predominantly residential and educational areas. PMID:26426030

  5. Study of atmospheric dynamics and pollution in the coastal area of English Channel using clustering technique

    NASA Astrophysics Data System (ADS)

    Sokolov, Anton; Dmitriev, Egor; Delbarre, Hervé; Augustin, Patrick; Gengembre, Cyril; Fourmenten, Marc

    2016-04-01

    The problem of atmospheric contamination by principal air pollutants was considered in the industrialized coastal region of English Channel in Dunkirk influenced by north European metropolitan areas. MESO-NH nested models were used for the simulation of the local atmospheric dynamics and the online calculation of Lagrangian backward trajectories with 15-minute temporal resolution and the horizontal resolution down to 500 m. The one-month mesoscale numerical simulation was coupled with local pollution measurements of volatile organic components, particulate matter, ozone, sulphur dioxide and nitrogen oxides. Principal atmospheric pathways were determined by clustering technique applied to backward trajectories simulated. Six clusters were obtained which describe local atmospheric dynamics, four winds blowing through the English Channel, one coming from the south, and the biggest cluster with small wind speeds. This last cluster includes mostly sea breeze events. The analysis of meteorological data and pollution measurements allows relating the principal atmospheric pathways with local air contamination events. It was shown that contamination events are mostly connected with a channelling of pollution from local sources and low-turbulent states of the local atmosphere.

  6. Metallic corrosion in the polluted urban atmosphere of Hong Kong.

    PubMed

    Liu, Bo; Wang, Da-Wei; Guo, Hai; Ling, Zhen-Hao; Cheung, Kalam

    2015-01-01

    This study aimed to explore the relationship between air pollutants, particularly acidic particles, and metallic material corrosion. An atmospheric corrosion test was carried out in spring-summer 2012 at a polluted urban site, i.e., Tung Chung in western Hong Kong. Nine types of metallic materials, namely iron, Q235 steel, 20# steel, 16Mn steel, copper, bronze, brass, aluminum, and aluminum alloy, were selected as specimens for corrosion tests. Ten sets of the nine materials were all exposed to ambient air, and then each set was collected individually after exposure to ambient air for consecutive 6, 13, 20, 27, 35, 42, 49, 56, 63, and 70 days, respectively. After the removal of the corrosion products on the surface of the exposed specimens, the corrosion rate of each material was determined. The surface structure of materials was observed using scanning electron microscopy (SEM) before and after the corrosion tests. Environmental factors including temperature, relative humidity, concentrations of gaseous pollutants, i.e., sulfur dioxide (SO₂), nitrogen dioxide (NO₂), carbon monoxide (CO), ozone (O₃), and particulate-phase pollutants, i.e., PM₂.₅ (FSP) and PM₁₀ (RSP), were monitored. Correlation analysis between environmental factors and corrosion rate of materials indicated that iron and carbon steel were damaged by both gaseous pollutants (SO₂ and NO₂) and particles. Copper and copper alloys were mainly corroded by gaseous pollutants (SO₂ and O₃), while corrosion of aluminum and aluminum alloy was mainly attributed to NO₂ and particles. PMID:25400029

  7. Long path DOAS measurements of atmospheric pollutants concentration

    NASA Astrophysics Data System (ADS)

    Geiko, Pavel P.; Smirnov, Sergey S.; Samokhvalov, Ignatii V.

    2015-11-01

    A differential optical absorption spectroscopy gas-analyzer consisted of a coaxial telescope, a spectrometer, an analyzer and retroreflector was successfully tested. A high pressure 150-W Xe arc lamp was employed as a light source. In order to record the spectra, a monochrometer with a grating and photodiode array was used. Gas analyzer spectral data bank includes more than 35 moleculas absorbed in UV spectral region. The measured absorption spectra were evaluated by using a least-squares fit to determine the average mixing ratio of each species in the atmosphere. As a result of experiments time series of concentrations of gases polluting the atmosphere were trace measured. Minimally detected concentration on pathlength 480 m is the unit of ppb at the time of accumulation of 2 min. The results of the field test measurements of pollutants in Tomsk city are presented.

  8. Atmospheric pollutants and hospital admissions due to pneumonia in children

    PubMed Central

    Negrisoli, Juliana; Nascimento, Luiz Fernando C.

    2013-01-01

    OBJECTIVE: To analyze the relationship between exposure to air pollutants and hospitalizations due to pneumonia in children of Sorocaba, São Paulo, Brazil. METHODS: Time series ecological study, from 2007 to 2008. Daily data were obtained from the State Environmental Agency for Pollution Control for particulate matter, nitric oxide, nitrogen dioxide, ozone, besides air temperature and relative humidity. The data concerning pneumonia admissions were collected in the public health system of Sorocaba. Correlations between the variables of interest using Pearson cofficient were calculated. Models with lags from zero to five days after exposure to pollutants were performed to analyze the association between the exposure to environmental pollutants and hospital admissions. The analysis used the generalized linear model of Poisson regression, being significant p<0.05. RESULTS: There were 1,825 admissions for pneumonia, with a daily mean of 2.5±2.1. There was a strong correlation between pollutants and hospital admissions, except for ozone. Regarding the Poisson regression analysis with the multi-pollutant model, only nitrogen dioxide was statistically significant in the same day (relative risk - RR=1.016), as well as particulate matter with a lag of four days (RR=1.009) after exposure to pollutants. CONCLUSIONS: There was an acute effect of exposure to nitrogen dioxide and a later effect of exposure to particulate matter on children hospitalizations for pneumonia in Sorocaba. PMID:24473956

  9. Changes in atmospheric lead and other pollution elements at Bermuda

    NASA Astrophysics Data System (ADS)

    Huang, Suilou; Arimoto, Richard; Rahn, Kenneth A.

    1996-09-01

    Measurements of atmospheric lead at Bermuda during the Atmosphere-Ocean Chemistry Experiments (AEROCE) in 1993-1994 showed that annual-mean concentrations had decreased by an order of magnitude from the 1970s and by a factor of 4 since the 1980s. Seasonal patterns had changed as well, with lead no longer being highest during winter. Both changes are consistent with decreased use of leaded gasoline in North America. Pollution-derived zinc and antimony also decreased, probably because of reduced smelting in the United States or changed atmospheric transport to Bermuda. Lead/aluminum mass ratios depended on direction: 0.04 with western air-mass trajectories (pollution from North America) versus 0.0001 and 0.0003 with eastern trajectories. The eastern Pb/Al ratios were indistinguishable from typical crustal values of 0.0002. The lower eastern ratio probably represents pure Saharan dust, while the higher ratio may indicate minor amounts of superimposed pollution aerosol, possibly from Europe or the Mediterranean area. Crustal lead was not evident in the 1970s because more lead was emitted from gasoline and dust transport from the Sahara was weaker.

  10. Model atmospheres for Betelgeuse.

    NASA Technical Reports Server (NTRS)

    Fay, T. D.; Johnson, H. R.

    1973-01-01

    Detailed comparison of a series of stellar atmospheric models at effective temperatures of 3800 and 3500 K with scanner observations of Betelgeuse (alpha Ori, M2 Iab). The atmospheres are hydrostatic, flux-constant, LTE atmospheres which include the opacity of H2O, CO, CN, and atomic line blanketing. To reduce the flux shortward of 6000 A enough to agree with observations requires either strong atomic line blanketing (or a similar opacity source) or significant reddening, or (likely) both. The visual extinction (an estimate of which depends strongly on the line blanketing, especially in the 1- to 2-micron region) lies between 0.4 and 2.0 mag. Comparison of predicted strengths of observed CO and CN features with observations and of predicted column densities of CO, OH, NH, and H2O with published column densities suggests that C/H may be less than its solar value by about a factor of 10 and C/O may be less than 0.6 in Betelgeuse.

  11. Global Reference Atmosphere Model (GRAM)

    NASA Technical Reports Server (NTRS)

    Woodrum, A. W.

    1989-01-01

    GRAM series of four-dimensional atmospheric model validated by years of data. GRAM program, still available. More current are Gram 86, which includes atmospheric data from 1986 and runs on DEC VAX, and GRAM 88, which runs on IBM 3084. Program generates altitude profiles of atmospheric parameters along any simulated trajectory through atmosphere, and also useful for global circulation and diffusion studies.

  12. Organics in the atmosphere: From air pollution to biogeochemical cycles and climate (Vilhelm Bjerknes Medal)

    NASA Astrophysics Data System (ADS)

    Kanakidou, Maria

    2016-04-01

    Organics are key players in the biosphere-atmosphere-climate interactions. They have also a significant anthropogenic component due to primary emissions or interactions with pollution. The organic pool in the atmosphere is a complex mixture of compounds of variable reactivity and properties, variable content in C, H, O, N and other elements depending on their origin and their history in the atmosphere. Multiphase atmospheric chemistry is known to produce organic acids with high oxygen content, like oxalic acid. This water soluble organic bi-acid is used as indicator for cloud processing and can form complexes with atmospheric Iron, affecting Iron solubility. Organics are also carriers of other nutrients like nitrogen and phosphorus. They also interact with solar radiation and with atmospheric water impacting on climate. In line with this vision for the role of organics in the atmosphere, we present results from a global 3-dimensional chemistry-transport model on the role of gaseous and particulate organics in atmospheric chemistry, accounting for multiphase chemistry and aerosol ageing in the atmosphere as well as nutrients emissions, atmospheric transport and deposition. Historical simulations and projections highlight the human impact on air quality and atmospheric deposition to the oceans. The results are put in the context of climate change. Uncertainties and implications of our findings for biogeochemical and climate modeling are discussed.

  13. High altitude atmospheric modeling

    NASA Technical Reports Server (NTRS)

    Hedin, Alan E.

    1988-01-01

    Five empirical models were compared with 13 data sets, including both atmospheric drag-based data and mass spectrometer data. The most recently published model, MSIS-86, was found to be the best model overall with an accuracy around 15 percent. The excellent overall agreement of the mass spectrometer-based MSIS models with the drag data, including both the older data from orbital decay and the newer accelerometer data, suggests that the absolute calibration of the (ensemble of) mass spectrometers and the assumed drag coefficient in the atomic oxygen regime are consistent to 5 percent. This study illustrates a number of reasons for the current accuracy limit such as calibration accuracy and unmodeled trends. Nevertheless, the largest variations in total density in the thermosphere are accounted for, to a very high degree, by existing models. The greatest potential for improvements is in areas where we still have insufficient data (like the lower thermosphere or exosphere), where there are disagreements in technique (such as the exosphere) which can be resolved, or wherever generally more accurate measurements become available.

  14. Sources of Atmospheric Pollutants Impacting Air and Water Quality in the Lake Tahoe Basin

    NASA Astrophysics Data System (ADS)

    Gertler, A. W.; Cahill, T. A.; Gillies, J.; Kuhns, H.

    2008-12-01

    Starting in the second half of the 20th century, decline in Lake Tahoe's water clarity and degradation in the basin's air quality have become major concerns due to its unique scenic features. Gaseous and particulate nitrogen (N) and particulate phosphorus (P) loading via direct atmospheric deposition and sediment transport to the lake have also been implicated as responsible for its eutrophication and decline in water clarity. Estimates suggest that atmospheric N deposition contributes 55% of the total N loading to the lake, while atmospheric P deposition contributes 15% of the total P loading. In order to improve both air quality and, as a consequence, water quality, it is necessary to develop an understanding of the sources of the atmospheric pollutants. Once this is accomplished, it is possible to implement cost-effective strategies to reduce this impact. This paper summarizes the findings of a series of studies performed to determine the levels and sources of ambient air pollutants in the basin. Projects have included the development of a Tahoe-specific emissions inventory, long-term measurements of road dust resuspension, modeling to determine the fraction of pollutants coming from in-basin vs. out-of-basin sources, particulate source apportionment, and estimates of nitric acid deposition. These studies found that the pollutants most closely connected to the decline in water quality come largely from within basin sources, as opposed to those coming from the Central Valley and upwind urban areas of California. These results indicate regulators need to control pollutant emissions within the Tahoe basin in order to reduce the impact of atmospheric pollutants on both air and water quality.

  15. [Comprehensive study of lead pollution in atmospheric aerosol of Shanghai].

    PubMed

    Zhang, Gui-lin; Tan, Ming-guang; Li, Xiao-lin; Zhang, Yuan-xun; Yue, Wei-sheng; Chen, Jian-min; Wang, Yin-song; Li, Ai-guo; Li, Yan; Zhang, Yuan-mao; Shan, Zhu-ci

    2006-05-01

    The lead contamination, lead species and source assignment were studied by a combination of several analytical techniques such as Proton-induced X-ray emission analysis (PIXE), Proton microprobe (micro-PIXE), Inductively coupled plasma-mass spectrometry (ICP-MS) and extended X-ray absorption fine structure (EXAFS) techniques. The results indicate that the lead concentration in the air of Shanghai gradually decreased over the last years. The atmospheric lead concentration of PM10 in the winter of 2002 was 369 ng x m(-3), which had declined by 28% in 2001, and in the winter of 2003 it decreased further to 237 ng x m(-3). The main lead species in the samples collected in the winter of 2003 were probably PbCl2, PbSO4 and PbO. The source apportionment was calculated in terms of the combination of lead isotope ratios and lead mass balance method, assisted by single particle analysis with micro-PIXE and pattern recognition. The results suggest that the major contributors of atmospheric lead pollution in Shanghai are the coal combustion dust; the metallurgic dust and vehicle exhaust particles, with a contribution around 50%, 35% and 15%, respectively. It probably is the first time to give a city a quantitative estimation of lead pollution contribution from emission sources. The influence from leaded gasoline was still present in the atmosphere by four or five years after the phasing out of leaded gasoline. PMID:16850817

  16. Understanding global cycling of atmosphere-surface exchangeable pollutants and its implications

    NASA Astrophysics Data System (ADS)

    Selin, N. E.; Giang, A.; Song, S.; Pike-thackray, C.; Friedman, C. L.

    2014-12-01

    We combine modeling approaches with data analysis to provide quantitative constraints on the global biogeochemical cycling of pollutants such as mercury (Hg) and persistent organic pollutants (POPs). These pollutants, released by human activities, continue to cycle between land, ocean, and atmosphere surfaces, extending their effective lifetimes in the environment. Measurement data are limited for all of these substances, providing few constraints on the magnitude of surface-atmosphere fluxes and thus the timescales of their cycling. This limits our ability to trace emissions to impacts for these substances, particularly in the context of both ongoing policies and climate change. We present a suite of modeling and analysis tools, including uncertainty analysis, that can provide quantitative constraints on cycling for these data-limited problems, and we illustrate their applicability through examples of Hg and selected POPs. Specifically, we summarize recent insights from inverse modeling of mercury, polynomial chaos-based methods for PAHs. Finally, we assess how uncertainty in timescales affects the entire emissions-to-impacts pathway for atmosphere-surface exchangeable pollutants. We discuss the implications of this analysis for policies under the Stockholm and Minamata Conventions.

  17. Atmospheric Pollution and Emission Sources in South Asian Urban Region

    NASA Astrophysics Data System (ADS)

    Biswas, K. F.; Husain, Liaquat

    2009-04-01

    Rapid urbanization, and lack of efficient monitoring and control of pollution, along with phenomena like Asian Brown Haze or prolonged episodes of winter fog, makes the South Asian atmospheric chemistry a very complex one. The anthropogenic aerosols released from this region are projected to become the dominant component of anthropogenic aerosols worldwide in the next 25 years (Nakicenovic and Swart, 2000). The region is one of the most densely populated in the world, with present population densities of 100-500 persons km-2. There are six big cities, namely, Delhi, Dhaka, Karachi, Kolkata, Lahore, and Mumbai, each housing a population around or above 10 million. There is now a real concern about the sustainability of the region's ability to support the population due to air pollution, loss of biodiversity and soil degradation. Therefore, we conducted several extensive campaigns over last 10 years in Lahore, Karachi, and Islamabad in Pakistan to (1) chemically characterize the aerosols (PM2.5 mass, concentrations of trace elements, ions, black and organic carbon), and gaseous pollutants (concentrations of NH3, SO2, HONO, HNO3, HCl and (COOH)2, and (2) identify the major emission sources in this region. Exceedingly high concentrations of all species, relative to major urban areas of US and Europe, were observed. Concentrations of PM2.5, BC, Pb, SO42-, NH4+, HONO, NH3 respectively, up to 476, 110, 12, 66, 60, 19.6 and 50 μgm-3 were observed in these cities, which were far in excess of WHO and US EPA air quality standard (Biswas et al., 2008). We use air parcel back trajectories, intercomponent relationships and meteorological observations to explain chemistry and emission sources of aerosol constituents. Carbonaceous aerosols contributed up to 69% of the PM2.5 mass (Husain et al., 2007). Source apportionment was conducted using positive matrix factorization. The analysis has classified six emission sources of aerosol components, namely, industrial activities, wood

  18. [Review of urban nonpoint source pollution models].

    PubMed

    Wang, Long; Huang, Yue-Fei; Wang, Guang-Qian

    2010-10-01

    The development history of urban nonpoint source pollution models is reviewed. Features, applicability and limitations of seven popular urban nonpoint source pollution models (SWMM, STORM, SLAMM, HSPF, DR3M-QUAL, MOUSE, and HydroWorks) are discussed. The methodology and research findings of uncertainty in urban nonpoint source pollution modeling are presented. Analytical probabilistic models for estimation of urban nonpoint sources are also presented. The research achievements of urban nonpoint source pollution models in China are summarized. The shortcomings and gaps of approaches on urban nonpoint source pollution models are pointed out. Improvements in modeling of pollutants buildup and washoff, sediments and pollutants transport, and pollutants biochemical reactions are desired for those seven popular models. Most of the models developed by researchers in China are empirical models, so that they can only applied for specific small areas and have inadequate accuracy. Future approaches include improving capability in fate and transport simulation of sediments and pollutants, exploring methodologies of modeling urban nonpoint source pollution in regions with little data or incomplete information, developing stochastic models for urban nonpoint source pollution simulation, and applying GIS to facilitate urban nonpoint source pollution simulation. PMID:21229773

  19. Climate and atmospheric modeling studies

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The climate and atmosphere modeling research programs have concentrated on the development of appropriate atmospheric and upper ocean models, and preliminary applications of these models. Principal models are a one-dimensional radiative-convective model, a three-dimensional global model, and an upper ocean model. Principal applications were the study of the impact of CO2, aerosols, and the solar 'constant' on climate.

  20. RESIDENCE TIME OF ATMOSPHERIC POLLUTANTS AND LONG-RANGE TRANSPORT

    EPA Science Inventory

    The Lagrangian trajectory model which is suitable for the study of long-range transport of pollutants, is developed. The computer program is capable of calculating trajectories over the region of the U.S. using routine sounding data. The output consists of tables of locations of ...

  1. Atmosphere-surface exchange and long-range transport of persistent organic pollutants

    SciTech Connect

    Pul, W.A.J. van; Jaarsveld, J.A. van; Jacobs, C.M.J.

    1996-12-31

    Persistent Organic Pollutants (POPs) are compounds that are resistant to photolytic, biological and chemical degradation. Many POPs are semi-volatile at atmospheric conditions. Because of these characteristics POPs have a atmospheric lifetime of weeks or more and are subject to long-range atmospheric transport. During this transport POPs can be deposited as well as be re-emitted from soil and water bodies. In this study a model for the exchange of POP at the soil and sea surface is presented as well as its application in a long-range atmospheric transport model. The main goal of this study is to simulate the spatial distribution of POP deposition (accumulation) over Europe.

  2. Cluster Analysis of Atmospheric Dynamics and Pollution Transport in a Coastal Area

    NASA Astrophysics Data System (ADS)

    Sokolov, Anton; Dmitriev, Egor; Maksimovich, Elena; Delbarre, Hervé; Augustin, Patrick; Gengembre, Cyril; Fourmentin, Marc; Locoge, Nadine

    2016-06-01

    Summertime atmospheric dynamics in the coastal zone of the industrialized Dunkerque agglomeration in northern France was characterized by a cluster analysis of back trajectories in the context of pollution transport. The MESO-NH atmospheric model was used to simulate the local dynamics at multiple scales with horizontal resolution down to 500 m, and for the online calculation of the Lagrangian backward trajectories with 30-min temporal resolution. Airmass transport was performed along six principal pathways obtained by the weighted k-means clustering technique. Four of these centroids corresponded to a range of wind speeds over the English Channel: two for wind directions from the north-east and two from the south-west. Another pathway corresponded to a south-westerly continental transport. The backward trajectories of the largest and most dispersed sixth cluster contained low wind speeds, including sea-breeze circulations. Based on analyses of meteorological data and pollution measurements, the principal atmospheric pathways were related to local air-contamination events. Continuous air quality and meteorological data were collected during the Benzene-Toluene-Ethylbenzene-Xylene 2006 campaign. The sites of the pollution measurements served as the endpoints for the backward trajectories. Pollutant transport pathways corresponding to the highest air contamination were defined.

  3. Thermal atmospheric models

    NASA Technical Reports Server (NTRS)

    Johnson, Hollis Ralph

    1987-01-01

    The static thermal atmosphere is described and its predictions are compared to observations both to test the validity of the classic assumptions and to distinguish and describe those spectral features with diagnostic value.

  4. Models of Mars' atmosphere (1974)

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Atmospheric models for support of design and mission planning of space vehicles that are to orbit the planet Mars, enter its atmosphere, or land on the surface are presented. Quantitative data for the Martian atmosphere were obtained from Earth-base observations and from spacecraft that have orbited Mars or passed within several planetary radii. These data were used in conjunction with existing theories of planetary atmospheres to predict other characteristics of the Martian atmosphere. Earth-based observations provided information on the composition, temperature, and optical properties of Mars with rather coarse spatial resolution, whereas spacecraft measurements yielded data on composition, temperature, pressure, density, and atmospheric structure with moderately good spatial resolution. The models provide the temperature, pressure, and density profiles required to perform basic aerodynamic analyses. The profiles are supplemented by computed values of viscosity, specific heat, and speed of sound.

  5. ON THE USE OF NEXRAD STAGE IV DATA IN THE MULTIMEDIA MODELING OF POLLUTANT TRANSPORT

    EPA Science Inventory

    The Environmental Protection Agency (EPA) is designing the Multimedia Integrated Modeling System (MIMS) to model the cycling of pollutants and nutrients between the atmosphere and the earth's surface, including water bodies and groundwater. Our ability to accurately model both ...

  6. An advanced open path atmospheric pollution monitor for large areas

    SciTech Connect

    Taylor, L.; Suhre, D.; Mani, S.

    1996-12-31

    Over 100 million gallons of radioactive and toxic waste materials generated in weapon materials production are stored in 322 tanks buried within large areas at DOE sites. Toxic vapors occur in the tank headspace due to the solvents used and chemical reactions within the tanks. To prevent flammable or explosive concentration of volatile vapors, the headspace are vented, either manually or automatically, to the atmosphere when the headspace pressure exceeds preset values. Furthermore, 67 of the 177 tanks at the DOE Hanford Site are suspected or are known to be leaking into the ground. These underground storage tanks are grouped into tank farms which contain closely spaced tanks in areas as large as 1 km{sup 2}. The objective of this program is to protect DOE personnel and the public by monitoring the air above these tank farms for toxic air pollutants without the monitor entering the tanks farms, which can be radioactive. A secondary objective is to protect personnel by monitoring the air above buried 50 gallon drums containing moderately low radioactive materials but which could also emit toxic air pollutants.

  7. Modeling of Atmosphere Revitalization

    NASA Technical Reports Server (NTRS)

    Coker, Robert; Knox, James; Kittredge, Kenneth

    2012-01-01

    NASA's AES is pioneering new approaches for future human missions beyond Earth orbit. All spacecraft systems must be minimized with respect to mass, power, and volume. Here, we show work related to improving system efficiency and reliability for water separation systems on crewed vehicles and the initial development of COMSOL simulations in support of the Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project

  8. Laser-excited fluorescence for measuring atmospheric pollution

    NASA Technical Reports Server (NTRS)

    Menzies, R. T.

    1975-01-01

    System measures amount of given pollutant at specific location. Infrared laser aimed at location has wavelength that will cause molecules of pollutant to fluoresce. Detector separates fluorescence from other radiation and measures its intensity to indicate concentration of pollutant.

  9. Modeling atmospheric concentrations and deposition of Hg

    SciTech Connect

    Shannon, J.D.

    1994-06-01

    The deleterious effects on ecosystems of mercury pollution are well established and fish advisories are in effect for many lakes in North America. Because methylation and other transformation processes in ecosystems can alter the original speciation of deposited Hg, a decrease in atmospheric loading of Hg in all forms is highly desirable. The contribution to Hg deposition by emissions from current anthropogenic activities relative to the deposition contribution by emissions from natural processes must be estimated to establish what fraction of atmospheric loading to watersheds and ecosystems is at least potentially amenable to control actions. Additional modeling questions concern source-receptor relationships (SRR) for major point sources and for emissions aggregated over geopolitical regions or emission sectors, because of the usefulness of SRR in comparing effectiveness of alternate control strategies. Modeling of atmospheric Hg is less advanced than that of some other widespread air pollution problems such as acid deposition. Nonetheless, several promising studies have been made for northern Europe and North America. For this study of Hg deposition in eastern North America we extend modeling techniques used extensively and successfully during the last 15 years for concentrations and deposition of SO{sub x} and NO{sub x} over regional scales, with parameterization rates adjusted to suitable values for Hg transformation and removal.

  10. Global Reference Atmosphere Model (GRAM)

    NASA Technical Reports Server (NTRS)

    Johnson, D. L.; Blocker, Rhonda; Justus, C. G.

    1993-01-01

    4D model provides atmospheric parameter values either automatically at positions along linear path or along any set of connected positions specified by user. Based on actual data, GRAM provides thermal wind shear for monthly mean winds, percent deviation from standard atmosphere, mean vertical wind, and perturbation data for each position.

  11. PC - POLLUTANT ROUTING MODEL (PC-PROUTE)

    EPA Science Inventory

    The PC - Pollutant Routing Model (PC-Proute) is a simple first order decay routing model that estimates aqueous pollutant concentrations on a reach by reach stream flow basis. PC-Proute is similar to the RGDS model; however it utilizes an improved method of estimating average rea...

  12. Lagrangian Modeling of the Atmosphere

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2013-08-01

    Like watching a balloon borne by the breeze, a Lagrangian model tracks a parcel of air as it flows through the atmosphere. Whether running forward or backward in time, Lagrangian models offer a powerful tool for tracking and understanding the fates, or origins, of atmospheric flows. In the AGU monograph Lagrangian Modeling of the Atmosphere, editors John Lin, Dominik Brunner, Christoph Gerbig, Andreas Stohl, Ashok Luhar, and Peter Webley explore the nuances of the modeling technique. In this interview Eos talks to Lin about the growing importance of Lagrangian modeling as the world settles on climate change mitigation strategies, the societal value of operational modeling, and how recent advances are making it possible to run these complex calculations at home.

  13. Titan atmospheric models intercomparison

    NASA Astrophysics Data System (ADS)

    Pernot, P.

    2008-09-01

    Several groups over the world have developed independently models of the photochemistry of Titan. The Cassini mission reveals daily that the chemical complexity is beyond our expectations e. g. observation of heavy positive and negative ions..., and the models are updated accordingly. At this stage, there is no consensus on the various input parameters, and it becomes increasingly difficult to compare outputs form different models. An ISSI team of experts of those models will be gathered shortly to proceed to an intercomparison, i.e. to assess how the models behave, given identical sets of inputs (collectively defined). Expected discrepancies will have to be elucidated and reduced. This intercomparison will also be an occasion to estimate explicitly the importance of various physicalchemical processes on model predictions versus observations. More robust and validated models are expected from this study for the interpretation of Titanrelated data.

  14. Numerical study of the effects of local atmospheric circulations on a pollution event over Beijing-Tianjin-Hebei, China.

    PubMed

    Miao, Yucong; Liu, Shuhua; Zheng, Yijia; Wang, Shu; Chen, Bicheng; Zheng, Hui; Zhao, Jingchuan

    2015-04-01

    Currently, the Chinese central government is considering plans to build a trilateral economic sphere in the Bohai Bay area, including Beijing, Tianjin and Hebei (BTH), where haze pollution frequently occurs. To achieve sustainable development, it is necessary to understand the physical mechanism of the haze pollution there. Therefore, the pollutant transport mechanisms of a haze event over the BTH region from 23 to 24 September 2011 were studied using the Weather Research and Forecasting model and the FLEXible-PARTicle dispersion model to understand the effects of the local atmospheric circulations and atmospheric boundary layer structure. Results suggested that the penetration by sea-breeze could strengthen the vertical dispersion by lifting up the planetary boundary layer height (PBLH) and carry the local pollutants to the downstream areas; in the early night, two elevated pollution layers (EPLs) may be generated over the mountain areas: the pollutants in the upper EPL at the altitude of 2-2.5 km were favored to disperse by long-range transport, while the lower EPL at the altitude of 1 km may serve as a reservoir, and the pollutants there could be transported downward and contribute to the surface air pollution. The intensity of the sea-land and mountain-valley breeze circulations played an important role in the vertical transport and distribution of pollutants. It was also found that the diurnal evolution of the PBLH is important for the vertical dispersion of the pollutants, which is strongly affected by the local atmospheric circulations and the distribution of urban areas. PMID:25872705

  15. Transport of pollutants; Summary review of physical dispersion models

    SciTech Connect

    Yadigaroglu, G. ); Munera, H.A. )

    1987-05-01

    The physical processes taking place during the dispersion of releases of pollutants into the atmosphere and the hydrosphere (surface as well as groundwaters) can be mathematically modeled. The analytical methods available for tracking pollutants in the atmosphere include local and mesoscale models (mostly based on Gaussian-plume dispersion), as well as regional and global models, where either more sophisticated numerical techniques or box modeling is used. Various removal processes such as physicochemical transformations, wet and dry deposition, resuspension, and plume rise affect aerial dispersion. The mechanisms of transport in surface waters include mass transport by the waters themselves, dispersion, sedimentation, boundary exchange processes, and various forms of depletion. The models vary according to the type of surface waters considered: rivers, estuaries and tidal rivers, small lakes, open-coast water bodies, etc.

  16. ATMOSPHERIC MODEL DEVELOPMENT

    EPA Science Inventory

    This task provides credible state of the art air quality models and guidance for use in implementation of National Ambient Air Quality Standards for ozone and PM. This research effort is to develop and improve air quality models, such as the Community Multiscale Air Quality (CMA...

  17. [Pollution Evaluation and Risk Assessment of Heavy Metals from Atmospheric Deposition in the Parks of Nanjing].

    PubMed

    Wang, Cheng; Qian, Xin; Li, Hui-ming; Sun, Yi-xuan; Wang, Jin-hua

    2016-05-15

    Contents of heavy metals involving As, Cd, Cr, Cu, Ni, Pb and Zn from atmospheric deposition in 10 parks of Nanjing were analyzed. The pollution level, ecological risk and health risk were evaluated using Geoaccumulation Index, Potential Ecological Risk Index and the US EPA Health Risk Assessment Model, respectively. The results showed that the pollution levels of heavy metals in Swallow Rock Park, Swallow Rock Park and Mochou Lake Park were higher than the others. Compared to other cities such as Changchun, Wuhan and Beijing, the contents of heavy metals in atmospheric deposition of parks in Nanjing were higher. The evaluation results of Geoaccumulation Index showed that Pb was at moderate pollution level, Zn and Cu were between moderate and serious levels, while Cd was between serious and extreme levels. The ecological risk level of Cd was high. The assessment results of Health Risk Assessment Model indicated that there was no non-carcinogenic risk for all the seven heavy metals. For carcinogenic risk, the risks of Cd, Cr and Ni were all negligible (Risk < 1 x 10⁻⁶), whereas As had carcinogenic risk possibility but was considered to be acceptable (10⁻⁶ < Risk < 10⁻⁴). PMID:27506017

  18. Tracking of atmospheric release of pollution using unmanned aerial vehicles

    NASA Astrophysics Data System (ADS)

    Šmídl, Václav; Hofman, Radek

    2013-03-01

    Tracking of an atmospheric release of pollution is usually based on measurements provided by stationary networks, occasionally complemented with deployment of mobile sensors. In this paper, we extend the existing concept to the case where the sensors are carried onboard of unmanned aerial vehicles (UAVs). The decision theoretic framework is used to design an unsupervised algorithm that navigates the UAVs to minimize the selected loss function. A particle filter with a problem-tailored proposal function was used as the underlying data assimilation procedure. A range of simulated twin experiments was performed on the problem of tracking an accidental release of radiation from a nuclear power plant in realistic settings. The main uncertainty was in the released activity and in parametric bias of the numerical weather forecast. It was shown that the UAVs can complement the existing stationary network to improve the accuracy of data assimilation. Moreover, two autonomously navigated UAVs alone were shown to provide assimilation results comparable to those obtained using the stationary network with more than thirty sensors.

  19. Range reference atmosphere models

    NASA Technical Reports Server (NTRS)

    Smith, O. E.; Galusha, B. W.

    1983-01-01

    A description is given of the methods used to establish the statistical parameters and models for wind and various thermodynamic quantities at an altitude of 0-70 km for nine geographical locations. It is noted that wind is modeled as a vector quantity using the bivariate normal probability function. With the five parameters of the bivariate normal distribution, the distribution for wind speed is derived as a generalized Rayleigh distribution. In addition, the frequency of wind direction is derived, and the conditional distribution of wind speed given the wind direction is derived. It is pointed out that these and other wind models are consistent with the rigorous mathematical properties of the bivariate normal probability theory. The thermodynamic quantities are consistent with the hydrostatic equation and the equation of state for the mean values. With these methods, many statistical relationships can be derived.

  20. Investigation of chemical properties and transport phenomena associated with pollutants in the atmospheric boundary layer

    NASA Astrophysics Data System (ADS)

    Holmes, Heather A.

    Under the Clean Air Act, the U.S. Environmental Protection Agency is required to determine which air pollutants are harmful to human health, then regulate, monitor and establish criteria levels for these pollutants. To accomplish this and for scientific advancement, integration of knowledge from several disciplines is required including: engineering, atmospheric science, chemistry and public health. Recently, a shift has been made to establish interdisciplinary research groups to better understand the atmospheric processes that govern the transport of pollutants and chemical reactions of species in the atmospheric boundary layer (ABL). The primary reason for interdisciplinary collaboration is the need for atmospheric processes to be treated as a coupled system, and to design experiments that measure meteorological, chemical and physical variables simultaneously so forecasting models can be improved (i.e., meteorological and chemical process models). This dissertation focuses on integrating research disciplines to provide a more complete framework to study pollutants in the ABL. For example, chemical characterization of particulate matter (PM) and the physical processes governing PM distribution and mixing are combined to provide more comprehensive data for source apportionment. Data from three field experiments were utilized to study turbulence, meteorological and chemical parameters in the ABL. Two air quality field studies were conducted on the U.S./Mexico border. The first was located in Yuma, AZ to investigate the spatial and temporal variability of PM in an urban environment and relate chemical properties of ambient aerosols to physical findings. The second border air quality study was conducted in Nogales, Sonora, Mexico to investigate the relationship between indoor and outdoor air quality in order to better correlate cooking fuel types and home activities to elevated indoor PM concentrations. The final study was executed in southern Idaho and focused on

  1. ATMOSPHERIC MODEL EVALUATION

    EPA Science Inventory

    Evaluation of the Models-3/CMAQ is conducted in this task. The focus is on evaluation of ozone, other photochemical oxidants, and fine particles using data from both routine monitoring networks and special, intensive field programs. Two types of evaluations are performed here: pe...

  2. NEAR ROADWAY RESEARCH IN THE ATMOSPHERIC MODELING DIVISION

    EPA Science Inventory

    This is a presentation to the CRC Mobile Source Air Toxics Workshop in Phoenix, AZ, on 23 October 2006. The presentation provides an overview of air quality modeling research in the USEPA/ORD/NERL's Atmospheric Modeling Division, with an emphasis on near-road pollutant character...

  3. Source regions of some persistent organic pollutants measured in the atmosphere at Birkenes, Norway

    NASA Astrophysics Data System (ADS)

    Eckhardt, S.; Breivik, K.; Li, Y. F.; Manø, S.; Stohl, A.

    2009-09-01

    A key feature of POPs (Persistent Organic Pollutants) is their potential for long-range atmospheric transport. In order to better understand and predict atmospheric source-receptor relationships of POPs, we have modified an existing Lagrangian transport model (FLEXPART) to include some of the key processes that control the atmospheric fate of POPs. We also present four years (2004-2007) of new atmospheric measurement data for polychlorinated biphenyls (PCBs) and hexachlorocyclohexanes (HCHs) obtained at Birkenes, an EMEP (European Monitoring and Evaluation Programme) site in southern Norway. The model overestimates measured PCB-28 and γ-HCH concentrations by factors of 2 and 8, respectively, which is most likely because the emissions used as input to the model are overestimated. FLEXPART captures the temporal variability in the measurements very well and, depending on season, explains 31-67% (14-62%) of the variance of measured PCB-28 (γ-HCH) concentrations. FLEXPART, run in a time-reversed (adjoint) mode, was used to identify the source regions responsible for the POP loading at the Birkenes station. Emissions in Central Europe and Eastern Europe contributed 32% and 24%, respectively, to PCB-28 at Birkenes, while Western Europe was found to be the dominant source (50%) for γ-HCH. Intercontinental transport from North America contributed 13% γ-HCH. While FLEXPART has no treatment of the partitioning of POPs between different surface media, it was found a very useful tool for studying atmospheric source-receptor relationships for POPs and POP-like chemicals that do not sorb strongly to atmospheric particles and whose atmospheric levels are believed to be mainly controlled by primary sources.

  4. Models for infrared atmospheric radiation

    NASA Technical Reports Server (NTRS)

    Tiwari, S. N.

    1976-01-01

    Line and band models for infrared spectral absorption are discussed. Radiative transmittance and integrated absorptance of Lorentz, Doppler, and voigt line profiles were compared for a range of parameters. It was found that, for the intermediate path lengths, the combined Lorentz-Doppler (Voigt) profile is essential in calculating the atmospheric transmittance. Narrow band model relations for absorptance were used to develop exact formulations for total absorption by four wide band models. Several continuous correlations for the absorption of a wide band model were compared with the numerical solutions of the wide band models. By employing the line-by-line and quasi-random band model formulations, computational procedures were developed for evaluating transmittance and upwelling atmospheric radiance. Homogeneous path transmittances were calculated for selected bands of CO, CO2, and N2O and compared with experimental measurements. The upwelling radiance and signal change in the wave number interval of the CO fundamental band were also calculated.

  5. The influence of scales of atmospheric motion on air pollution over Portugal

    NASA Astrophysics Data System (ADS)

    Russo, Ana; Trigo, Ricardo; Mendes, Manuel; Jerez, Sonia; Gouveia, Célia Marina

    2014-05-01

    sustainable management of environmental risks. [1] Demuzere, M., Trigo, R.M., Vila-Guerau de Arellano, van Lipzig, N.P.M., 2009. The impact of weather and atmospheric circulation on O3 and PM10 levels at a rural mid-latitude site. Atmos. Chem. Phys., 9, 2695-2714. [2] Levy, I., Dayan, U., Mahrer, Y., 2009. Differing atmospheric scales of motion and their impact on air pollutants. Int. J. Climatol. [3] Pearce, J., Beringer, J., Nicholls, N., Hyndman, R.J., Uotila, P., Tapper, N.J., 2011. Investigating the influence of synoptic-scale meteorology on air quality using self-organizing maps and generalized additive modeling. Atmospheric Environment, 45, 1, 128 - 136, doi 10.1016/j.atmosenv.2010.09.032. [4 Trigo, R.M., DaCamara, C.C., 2000. Circulation Weather Types and their impact on the precipitation regime in Portugal. Int. J. Climat., 20, 1559-1581. [5] Carvalho, A., Monteiro, A., Ribeiro, I., Tchepel, O., Miranda, A.I., Borrego, C., Saavedra, S., Souto, J.A., Casares, J.J., 2010. High ozone levels in the Northeast of Portugal: analysis and characterization. Atmospheric Environment, 44, 1020 - 1031. [6] Saavedra, S., Rodríguez, A., Taboada, J.J., Souto, J.A., Casares, J.J., 2012. Synoptic patterns and air mass transport during ozone episodes in northwestern Iberia. Sci Total Environ., 441, 97-110. doi: 10.1016/j.scitotenv.2012.09.014.

  6. Mathematical Modeling of Photochemical Air Pollution.

    NASA Astrophysics Data System (ADS)

    McRae, Gregory John

    Air pollution is an environmental problem that is both pervasive and difficult to control. An important element of any rational control approach is a reliable means for evaluating the air quality impact of alternative abatement measures. This work presents such a capability, in the form of a mathematical description of the production and transport of photochemical oxidants within an urban airshed. The combined influences of advection, turbulent diffusion, chemical reaction, emissions and surface removal processes are all incorporated into a series of models that are based on the species continuity equations. A delineation of the essential assumptions underlying the formulation of a three-dimensional, a Lagrangian trajectory, a vertically integrated and single cell air quality model is presented. Since each model employs common components and input data the simpler forms can be used for rapid screening calculations and the more complex ones for detailed evaluations. The flow fields, needed for species transport, are constructed using inverse distance weighted polynomial interpolation techniques that map routine monitoring data onto a regular computational mesh. Variational analysis procedures are then employed to adjust the field so that mass is conserved. Initial concentration and mixing height distributions can be established with the same interpolation algorithms. Subgrid scale turbulent transport is characterized by a gradient diffusion hypothesis. Similarity solutions are used to model the surface layer fluxes. Above this layer different treatments of turbulent diffusivity are required to account for variations in atmospheric stability. Convective velocity scaling is utilized to develop eddy diffusivities for unstable conditions. The predicted mixing times are in accord with results obtained during sulfur hexafluoride (SF(,6)) tracer experiments. Conventional models are employed for neutral and stable conditions. A new formulation for gaseous deposition fluxes

  7. Impact of a future H2 transportation on atmospheric pollution in Europe

    NASA Astrophysics Data System (ADS)

    Popa, Maria Elena; Segers, Arjo; Denier van der Gon, Hugo; Schaap, Martijn; Krol, Maarten; Visschedijk, Antoon; Röckmann, Thomas

    2014-05-01

    Traditionally fuelled road traffic is a major source of greenhouse gases and pollutants. Greenhouse gases (e.g. CO2 and CH4) affect the global atmosphere and contribute to global warming. The pollutants emitted by vehicles (e.g. CO, NOx, SO2, particulate matter, volatile organic compounds) are toxic for man and environment and decrease air quality especially in highly populated areas. Burning H2 produces only water, thus H2-powered vehicles are seen as a possibility to reduce greenhouse gas emissions and improve air quality; because of this, H2 usage as a fuel is foreseen to significantly increase in the future. Large scale usage of H2 as a fuel has the potential to affect the atmospheric composition in different ways. On one hand, emissions associated to fossil fuel burning will decrease. On the other hand, large quantities of H2 used will likely lead to increased H2 emissions from leakages during production, transport and storage. Additional H2 in the atmosphere will affect the chemistry of many species, in principal by decreasing the availability of OH radicals, with the result of increasing the lifetime of greenhouse gases and pollutants. Thus the net effect of H2 vehicles on the atmospheric composition depends on the relative strength of these two contrary effects. In order to evaluate the potential influence of a future H2 road transportation on local and regional air quality, we implemented H2 in the atmospheric transport and chemistry model LOTOS-EUROS. We simulated the future (2020) using emission scenarios with different proportions of H2 vehicles and different H2 leakage rates. The reference future scenario does not include H2 vehicles, and assumes that all present and planned European regulations for emissions are fully implemented. We find that in general the air quality in 2020 will be significantly better than at present in all scenarios, with and without H2 cars. In the future scenario without H2 cars, the pollution is reduced due to the strict

  8. Variational approach to direct and inverse problems of atmospheric pollution studies

    NASA Astrophysics Data System (ADS)

    Penenko, Vladimir; Tsvetova, Elena; Penenko, Alexey

    2016-04-01

    We present the development of a variational approach for solving interrelated problems of atmospheric hydrodynamics and chemistry concerning air pollution transport and transformations. The proposed approach allows us to carry out complex studies of different-scale physical and chemical processes using the methods of direct and inverse modeling [1-3]. We formulate the problems of risk/vulnerability and uncertainty assessment, sensitivity studies, variational data assimilation procedures [4], etc. A computational technology of constructing consistent mathematical models and methods of their numerical implementation is based on the variational principle in the weak constraint formulation specifically designed to account for uncertainties in models and observations. Algorithms for direct and inverse modeling are designed with the use of global and local adjoint problems. Implementing the idea of adjoint integrating factors provides unconditionally monotone and stable discrete-analytic approximations for convection-diffusion-reaction problems [5,6]. The general framework is applied to the direct and inverse problems for the models of transport and transformation of pollutants in Siberian and Arctic regions. The work has been partially supported by the RFBR grant 14-01-00125 and RAS Presidium Program I.33P. References: 1. V. Penenko, A.Baklanov, E. Tsvetova and A. Mahura . Direct and inverse problems in a variational concept of environmental modeling //Pure and Applied Geoph.(2012) v.169: 447-465. 2. V. V. Penenko, E. A. Tsvetova, and A. V. Penenko Development of variational approach for direct and inverse problems of atmospheric hydrodynamics and chemistry, Izvestiya, Atmospheric and Oceanic Physics, 2015, Vol. 51, No. 3, p. 311-319, DOI: 10.1134/S0001433815030093. 3. V.V. Penenko, E.A. Tsvetova, A.V. Penenko. Methods based on the joint use of models and observational data in the framework of variational approach to forecasting weather and atmospheric composition

  9. Pollutant Plume Dispersion in the Atmospheric Boundary Layer over Idealized Urban Roughness

    NASA Astrophysics Data System (ADS)

    Wong, Colman C. C.; Liu, Chun-Ho

    2013-05-01

    The Gaussian model of plume dispersion is commonly used for pollutant concentration estimates. However, its major parameters, dispersion coefficients, barely account for terrain configuration and surface roughness. Large-scale roughness elements (e.g. buildings in urban areas) can substantially modify the ground features together with the pollutant transport in the atmospheric boundary layer over urban roughness (also known as the urban boundary layer, UBL). This study is thus conceived to investigate how urban roughness affects the flow structure and vertical dispersion coefficient in the UBL. Large-eddy simulation (LES) is carried out to examine the plume dispersion from a ground-level pollutant (area) source over idealized street canyons for cross flows in neutral stratification. A range of building-height-to-street-width (aspect) ratios, covering the regimes of skimming flow, wake interference, and isolated roughness, is employed to control the surface roughness. Apart from the widely used aerodynamic resistance or roughness function, the friction factor is another suitable parameter that measures the drag imposed by urban roughness quantitatively. Previous results from laboratory experiments and mathematical modelling also support the aforementioned approach for both two- and three-dimensional roughness elements. Comparing the UBL plume behaviour, the LES results show that the pollutant dispersion strongly depends on the friction factor. Empirical studies reveal that the vertical dispersion coefficient increases with increasing friction factor in the skimming flow regime (lower resistance) but is more uniform in the regimes of wake interference and isolated roughness (higher resistance). Hence, it is proposed that the friction factor and flow regimes could be adopted concurrently for pollutant concentration estimate in the UBL over urban street canyons of different roughness.

  10. GREENHOUSE GAS RESEARCH AREAS (ATMOSPHERIC PROTECTION BRANCH, AIR POLLUTION PREVENTION AND CONTROL DIVISION, NRMRL)

    EPA Science Inventory

    The emissions programs in the Atmospheric Protection Branch (APB) of NRMRL's Air Pollution Prevention and Control Division are primarily dedicated to anthropogenic (human-influenced) sources of methane and high-global-warming refrigerants, though some work addresses carbon dioxid...

  11. GREENHOUSE GASES (ATMOSPHERIC PROTECTION BRANCH, AIR POLLUTION PREVENTION AND CONTROL DIVISION, NRMRL)

    EPA Science Inventory

    Greenhouse gas (GHG) emissions are projected for various scenarios and the most appropriate approaches and technologies for mitigation are identified by NRMRL's Air Pollution Prevention and Control Division's Atmospheric Protection Branch (APB). These methods contribute to reduct...

  12. Computational Modeling of Pollution Transmission in Rivers

    NASA Astrophysics Data System (ADS)

    Parsaie, Abbas; Haghiabi, Amir Hamzeh

    2015-08-01

    Modeling of river pollution contributes to better management of water quality and this will lead to the improvement of human health. The advection dispersion equation (ADE) is the government equation on pollutant transmission in the river. Modeling the pollution transmission includes numerical solution of the ADE and estimating the longitudinal dispersion coefficient (LDC). In this paper, a novel approach is proposed for numerical modeling of the pollution transmission in rivers. It is related to use both finite volume method as numerical method and artificial neural network (ANN) as soft computing technique together in simulation. In this approach, the result of the ANN for predicting the LDC was considered as input parameter for the numerical solution of the ADE. To validate the model performance in real engineering problems, the pollutant transmission in Severn River has been simulated. Comparison of the final model results with measured data of the Severn River showed that the model has good performance. Predicting the LDC by ANN model significantly improved the accuracy of computer simulation of the pollution transmission in river.

  13. ECONOMICS AND PERFORMANCE MODELING (AIR POLLUTION TECHNOLOGY BRANCH, AIR POLLUTION PREVENTION AND CONTROL DIVISION, NRMRL)

    EPA Science Inventory

    NRMRL's Air Pollution Prevention and Control Division's Air Pollution Technology Branch (APTB) is active in the development, refinement, and maintenance of economic and performance evaluation models that provide agency-wide support for estimating costs for air pollution preventio...

  14. ATMOSPHERIC MEASUREMENTS OF TRACE POLLUTANTS; LONG PATH FOURIER TRANSFORM INFRARED SPECTROSCOPY

    EPA Science Inventory

    Described are the results of a four-year study to measure trace pollutant concentrations in polluted atmospheres by kilometer pathlength Fourier transform infrared (FT-IR) absorption spectroscopy. The study covers selected smog episodes during the years 1976 to 1979. During 1976 ...

  15. Urban Climate Effects on Air Pollution and Atmospheric Chemistry

    NASA Astrophysics Data System (ADS)

    Rasoul, Tara; Bloss, William; Pope, Francis

    2016-04-01

    Tropospheric ozone, adversely affects the environment and human health. The presence of chlorine nitrate (ClNO2) in the troposphere can enhance ozone (O3) formation as it undergoes photolysis, releasing chlorine reactive atoms (Cl) and nitrogen dioxide (NO2), both of which enhance tropospheric ozone formation. The importance of new sources of tropospheric ClNO2 via heterogeneous processes has recently been highlighted. This study employed a box model, using the Master Chemical Mechanism (MCM version 3.2) to assess the effect of ClNO2 on air quality in urban areas within the UK. The model updated to include ClNO2 production, photolysis, a comprehensive parameterisation of dinitrogen pentoxide (N2O5) uptake, and ClNO2 production calculated from bulk aerosol composition. The model simulation revealed the presence of ClNO2 enhances the formation of NO2, organic peroxy radical (CH3O2), O3, and hydroxyl radicals (OH) when compared with simulations excluding ClNO2. In addition, the study examined the effect of temperature variation upon ClNO2 formation. The response of ClNO2 to temperature was analysed to identify the underlying drivers, of particular importance when assessing the response of atmospheric chemistry processes under potential future climates.

  16. Chemical modeling of exoplanet atmospheres

    NASA Astrophysics Data System (ADS)

    Venot, O.; Agúndez, M.

    2015-12-01

    The past twenty years have revealed the diversity of planets that exist in the Universe. It turned out that most of exoplanets are different from the planets of our Solar System and thus, everything about them needs to be explored. Thanks to current observational technologies, we are able to determine some information about the atmospheric composition the thermal structure and the dynamics of these exoplanets, but many questions remain still unanswered. To improve our knowledge about exoplanetary systems, more accurate observations are needed and that is why the Exoplanet Characterisation Observatory (EChO) is an essential space mission. Thanks to its large spectral coverage and high spectral resolution, EChO will provide exoplanetary spectra with an unprecedented accuracy, allowing to improve our understanding of exoplanets. In this work, we review what has been done to date concerning the chemical modeling of exoplanet atmospheres and what are the main characteristics of warm exoplanet atmospheres, which are one of the main targets of EChO. Finally we will present the ongoing developments that are necessary for the chemical modeling of exoplanet atmospheres.

  17. A spatial multicriteria model for determining air pollution at sample locations.

    PubMed

    Réquia Júnior, Weeberb João; Roig, Henrique Llacer; Koutrakis, Petros

    2015-02-01

    Atmospheric pollution in urban centers has been one of the main causes of human illness related to the respiratory and circulatory system. Efficient monitoring of air quality is a source of information for environmental management and public health. This study investigates the spatial patterns of atmospheric pollution using a spatial multicriteria model that helps target locations for air pollution monitoring sites. The main objective was to identify high-priority areas for measuring human exposures to air pollutants as they relate to emission sources. The method proved to be viable and flexible in its application to various areas. PMID:25947058

  18. Fluid mechanics simulation of fog formation associated with polluted atmosphere produced by energy related fuel combustion

    NASA Technical Reports Server (NTRS)

    Hung, R. J.; Liaw, G. S.

    1980-01-01

    It is noted that large quantities of atmospheric aerosols with composition SO4(-2), NO3(-1), and NH4(+1) have been detected in highly industrialized areas. Most aerosol products come from energy-related fuel combustion. Fluid mechanics simulation of both microphysical and macrophysical processes is considered in studying the time dependent evolution of the saturation spectra of condensation nuclei associated with polluted and clean atmospheres during the time periods of advection fog formation. The results demonstrate that the condensation nuclei associated with a polluted atmosphere provide more favorable conditions than condensation nuclei associated with a clean atmosphere to produce dense advection fog, and that attaining a certain degree of supersaturation is not necessarily required for the formation of advection fog having condensation nuclei associated with a polluted atmosphere.

  19. EFFECTS OF ATMOSPHERIC POLLUTANTS ON HUMAN PHYSIOLOGIC FUNCTION

    EPA Science Inventory

    Short-term health effects of common ambient air pollutants, particularly photochemical oxidants, were investigated under controlled conditions simulating typical ambient exposures. Volunteer subjects were exposed, in an environmental control chamber providing highly purified back...

  20. Atmospheric chemistry: Ozone pollution from near and far

    NASA Astrophysics Data System (ADS)

    Doherty, Ruth M.

    2015-09-01

    Tropospheric ozone is generated from precursor pollutants, but can be blown far afield. Satellite observations show rising ozone levels over China -- and almost stable levels over western North America despite stricter regulations.

  1. ONE ATMOSPHERE MODELING FOR AIR QUALITY: BUILDING PARTNERSHIPS THAT TRANSITION RESEARCH INTO APPLICATIONS

    EPA Science Inventory

    The Community Miultiscale Air Quality (CMAQ) modeling system is a "one atmosphere" chemical transport model that simulates the transport and fate of air pollutants from urban to continental scales and from daily to annual time intervals.

  2. Atmospheric emissions and pollution from the coal-fired thermal power plants in India

    NASA Astrophysics Data System (ADS)

    Guttikunda, Sarath K.; Jawahar, Puja

    2014-08-01

    In India, of the 210 GW electricity generation capacity, 66% is derived from coal, with planned additions of 76 GW and 93 GW during the 12th and the 13th five year plans, respectively. Atmospheric emissions from the coal-fired power plants are responsible for a large burden on human health. In 2010-11, 111 plants with an installed capacity of 121 GW, consumed 503 million tons of coal, and generated an estimated 580 ktons of particulates with diameter less than 2.5 μm (PM2.5), 2100 ktons of sulfur dioxides, 2000 ktons of nitrogen oxides, 1100 ktons of carbon monoxide, 100 ktons of volatile organic compounds, and 665 million tons of carbon dioxide. These emissions resulted in an estimated 80,000 to 115,000 premature deaths and 20.0 million asthma cases from exposure to PM2.5 pollution, which cost the public and the government an estimated INR 16,000 to 23,000 crores (USD 3.2 to 4.6 billion). The emissions were estimated for the individual plants and the atmospheric modeling was conducted using CAMx chemical transport model, coupled with plume rise functions and hourly meteorology. The analysis shows that aggressive pollution control regulations such as mandating flue gas desulfurization, introduction and tightening of emission standards for all criteria pollutants, and updating procedures for environment impact assessments, are imperative for regional clean air and to reduce health impacts. For example, a mandate for installation of flue gas desulfurization systems for the operational 111 plants could reduce the PM2.5 concentrations by 30-40% by eliminating the formation of the secondary sulfates and nitrates.

  3. Usefulness of the infrared heterodyne radiometer in remote sensing of atmospheric pollutants.

    NASA Technical Reports Server (NTRS)

    Menzies, R. T.; Shumate, M. S.

    1971-01-01

    The application of narrow-band optical receivers to the problem of sensing atmospheric pollution is discussed. The emission/absorption lines of many major atmospheric pollutant molecules overlap the operating frequency bands of CO2 laser and CO laser heterodyne receivers. Several remote pollution sensing systems which are based upon utilization of these spectral overlaps are described, and an analysis of their potential is presented. The possibility of using other lasers (e.g.: the PbSnTe tunable diode laser) as local oscillators is also considered. Results of laboratory experiments with a CO2 laser heterodyne radiometer are presented.

  4. The magnetic way of quantifying road traffic pollution in atmospheric particulate matter

    NASA Astrophysics Data System (ADS)

    Spassov, S.; Egli, R.; Heller, F.

    2003-12-01

    The steadily increasing number of motor vehicles requires continuous air quality monitoring in large urban and sub-urban areas. We present a fast and simple method for analysing samples of atmospheric particulate matter (PM) based on magnetic measurements, which is suitable for systematic pollution monitoring of extensive areas at low costs. Representative samples have been collected in Switzerland at sites with variable exposure to pollution sources. Atmospheric PM consists of natural and of anthropogenic components which both contain magnetic mineral fractions with specific magnetic properties. Our method relies on the analysis of the remanent magnetisation of PM samples. Detailed demagnetisation curves of anhysteretic remanent magnetisation (ARM) of these samples have been modelled using a linear combination of appropriate model functions, which represent the contribution of different magnetic mineral sources to the total magnetisation. Two magnetic components C1 and C2 with well-defined magnetic properties have been identified in all samples. The low-coercivity component C1 predominates in less polluted sites, whereas the concentration of the higher coercivity component C2 is large in urban areas. Once the coercivity distributions of C1 and C2 have been characterised, a simple method has been developed to quantify C1 and C2. This method is based on four-step demagnetisation curves, which can be measured in 12 minutes using a 2G cryogenic magnetometer with an in-line AF degausser. Our results are confirmed by independent chemical investigations at the same sites. The magnetic contribution of C2 is shown to be proportional to the chemically estimated total PM10 mass contribution of exhaust emissions. The mass concentration of traffic related elements in PM10 such as Fe, Ba, Cu, Mo, Br and elemental carbon also correlates with our results. Traffic is the most important PM pollution source in Switzerland: it includes exhaust emissions and abrasion products released

  5. Atmospheric transport of persistent pollutants governs uptake by holarctic terrestrial biota

    SciTech Connect

    Larsson, P.; Okla, L.; Woin, Per )

    1990-10-01

    The atmospheric deposition of PCBs, DDT, and lindane, governed uptake in terrestrial biota in the Scandinavian peninsula. Mammalian herbivores and predators as well as predatory insects contained higher levels of pollutants at locations where the fallout load was high than at stations where atmospheric deposition was lower, and the two variables were significantly correlated.

  6. Effects of atmospheric deposition of energy-related pollutants on water quality: a review and assessment

    SciTech Connect

    Davis, M.J.

    1981-05-01

    The effects on surface-water quality of atmospheric pollutants that are generated during energy production are reviewed and evaluated. Atmospheric inputs from such sources to the aquatic environment may include trace elements, organic compounds, radionuclides, and acids. Combustion is the largest energy-related source of trace-element emissions to the atmosphere. This report reviews the nature of these emissions from coal-fired power plants and discusses their terrestrial and aquatic effects following deposition. Several simple models for lakes and streams are developed and are applied to assess the potential for adverse effects on surface-water quality of trace-element emissions from coal combustion. The probability of acute impacts on the aquatic environment appears to be low; however, more subtle, chronic effects are possible. The character of acid precipitation is reviewed, with emphasis on aquatic effects, and the nature of existing or potential effects on water quality, aquatic biota, and water supply is considered. The response of the aquatic environment to acid precipitation depends on the type of soils and bedrock in a watershed and the chemical characteristics of the water bodies in question. Methods for identifying regions sensitive to acid inputs are reviewed. The observed impact of acid precipitation ranges from no effects to elimination of fish populations. Coal-fired power plants and various stages of the nuclear fuel cycle release radionuclides to the atmosphere. Radioactive releases to the atmosphere from these sources and the possible aquatic effects of such releases are examined. For the nuclear fuel cycle, the major releases are from reactors and reprocessing. Although aquatic effects of atmospheric releases have not been fully quantified, there seems little reason for concern for man or aquatic biota.

  7. VALMET-A valley air pollution model

    SciTech Connect

    Whiteman, C.D.; Allwine, K.J.

    1983-09-01

    Following a thorough analysis of meteorological data obtained from deep valleys of western Colorado, a modular air-pollution model has been developed to simulate the transport and diffusion of pollutants released from an elevated point source in a well-defined mountain valley during the nighttime and morning transition periods. This initial version of the model, named VALMET, operates on a valley cross section at an arbitrary distance down-valley from a continuous point source. The model has been constructed to include parameterizations of the major physical processes that act to disperse pollution during these time periods. The model has not been fully evaluated. Further testing, evaluations, and development of the model are needed. Priorities for further development and testing are provided.

  8. Significant atmospheric aerosol pollution caused by world food cultivation

    NASA Astrophysics Data System (ADS)

    Bauer, Susanne E.; Tsigaridis, Kostas; Miller, Ron

    2016-05-01

    Particulate matter is a major concern for public health, causing cancer and cardiopulmonary mortality. Therefore, governments in most industrialized countries monitor and set limits for particulate matter. To assist policy makers, it is important to connect the chemical composition and severity of particulate pollution to its sources. Here we show how agricultural practices, livestock production, and the use of nitrogen fertilizers impact near-surface air quality. In many densely populated areas, aerosols formed from gases that are released by fertilizer application and animal husbandry dominate over the combined contributions from all other anthropogenic pollution. Here we test reduction scenarios of combustion-based and agricultural emissions that could lower air pollution. For a future scenario, we find opposite trends, decreasing nitrate aerosol formation near the surface while total tropospheric loads increase. This suggests that food production could be increased to match the growing global population without sacrificing air quality if combustion emission is decreased.

  9. Significant Atmospheric Aerosol Pollution Caused by World Food Cultivation

    NASA Technical Reports Server (NTRS)

    Bauer, Susanne E.; Tsigaridis, Kostas; Miller, Ron

    2016-01-01

    Particulate matter is a major concern for public health, causing cancer and cardiopulmonary mortality. Therefore, governments in most industrialized countries monitor and set limits for particulate matter. To assist policy makers, it is important to connect the chemical composition and severity of particulate pollution to its sources. Here we show how agricultural practices, livestock production, and the use of nitrogen fertilizers impact near-surface air quality. In many densely populated areas, aerosols formed from gases that are released by fertilizer application and animal husbandry dominate over the combined contributions from all other anthropogenic pollution. Here we test reduction scenarios of combustion-based and agricultural emissions that could lower air pollution. For a future scenario, we find opposite trends, decreasing nitrate aerosol formation near the surface while total tropospheric loads increase. This suggests that food production could be increased to match the growing global population without sacrificing air quality if combustion emission is decreased.

  10. Low level atmospheric sulfur dioxide pollution and childhood asthma

    SciTech Connect

    Tseng, R.Y.; Li, C.K. )

    1990-11-01

    Quarterly analysis (1983-1987) of childhood asthma in Hong Kong from 13,620 hospitalization episodes in relation to levels of pollutants (SO{sub 2}, NO{sub 2}, NO, O{sub 3}, TSP, and RSP) revealed a seasonal pattern of attack rates that correlates inversely with exposure to sulfur dioxide (r = -.52, P less than .05). The same cannot be found with other pollutants. Many factors may contribute to the seasonal variation of asthma attacks. We speculate that prolonged exposure (in terms of months) to low level SO{sub 2} is one factor that might induce airway inflammation and bronchial hyperreactivity and predispose to episodes of asthma.

  11. Multiwavelength Modeling of Nove Atmospheres

    NASA Technical Reports Server (NTRS)

    Huschildt, P. H.

    2001-01-01

    LMC 1988 #1 was a slow, CO type, dust forming classical nova. It was the first extragalactic nova to be observed with the IUE satellite. We have successfully fitted observed ultraviolet and optical spectra of LMC 1988 #1 taken within the first two months of its outburst (when the atmosphere was still optically thick) with synthetic spectra computed using PHOENIX nova model atmospheres. The synthetic spectra reproduce most of the features seen in the spectra and provide V band magnitudes consistent with the observed light curve. The fits are improved by increasing the CNO abundances to 10 times the solar values. The bolometric luminosity of LMC 1988 #1 was approximately constant at 2 x 10(exp 38) ergs per second at a distance of 47.3 kpc for the first 2 months of the outburst until the formation of the dust shell.

  12. Evaluation of satellites and remote sensors for atmospheric pollution measurements

    NASA Technical Reports Server (NTRS)

    Carmichael, J.; Eldridge, R.; Friedman, E.; Keitz, E.

    1976-01-01

    An approach to the development of a prioritized list of scientific goals in atmospheric research is provided. The results of the analysis are used to estimate the contribution of various spacecraft/remote sensor combinations for each of several important constituents of the stratosphere. The evaluation of the combinations includes both single-instrument and multiple-instrument payloads. Attention was turned to the physical and chemical features of the atmosphere as well as the performance capability of a number of atmospheric remote sensors. In addition, various orbit considerations were reviewed along with detailed information on stratospheric aerosols and the impact of spacecraft environment on the operation of the sensors.

  13. POLLUTANT SAMPLER FOR MEASUREMENTS OF ATMOSPHERIC ACIDIC DRY DEPOSITION

    EPA Science Inventory

    An acidic pollutant sampler for dry deposition monitoring has been designed and evaluated in laboratory and field studies. The system, which is modular and simple to operate, samples gaseous HNO3, NH3, SO2 and NO2 and particulate SO4(-2), NO3(1-) and NH4(1+) and is made of Teflon...

  14. Atmospheric transport of persistent organic pollutants (POPs) to Bjørnøya (Bear island).

    PubMed

    Kallenborn, Roland; Christensen, Guttorm; Evenset, Anita; Schlabach, Martin; Stohl, Andreas

    2007-10-01

    A first medium term monitoring of atmospheric transport and distribution for persistent organic pollutants (POPs) in Bjørnøya (Bear island) air samples has been performed in the period between week 51/1999 and week 28/2003. A total of 50 single compounds consisting of polychlorinated biphenyls (33 congeners), hexachlorobenzene (HCB), hexachlorocyclohexane isomers (alpha-, beta-, gamma-HCH), alpha-endosulfan, cyclodiene pesticides (chlordanes, nonachlor-isomers, oxy-chlordane, heptachlor and chlordane) as well as dichlorodiphenyltrichloroethane (DDT) derivatives were analysed and quantified. Atmospheric transport of POPs was identified as an important contamination source for the island. PCBs, HCB and HCH isomers were the predominant POP groups, contributing with 70-90% to the overall POP burden quantified in the Bjørnøya air samples. The highest concentration levels for a single compound were found for HCB (25-35 pg m(-3)). However, the sum of 33 PCB congeners was found to be in the same concentration range (annual means between 15 and 30 pg m(-3)). Cyclodiene pesticides, DDT derivatives and alpha-endosulfan were identified as minor contaminants. Several atmospheric long-range transport episodes were identified and characterised. Indications for industrial emissions as well as agricultural sources were found for the respective atmospheric transport episodes. A first simple statistical correlation assessment showed that for long-range transport of pollution, the local meteorological situation is not as important as the air mass properties integrated over the time period of the transport event. The local weather situation, on the other hand, is important when investigating deposition rates and up-take/accumulation properties in the local ecosystem. Based upon chemical data interpretation, valuable information about the influence of primary and secondary sources on the air mass contamination with chlorinated insecticides (e.g., HCHs) was found and discussed. The

  15. Photochemical modeling of Titan's atmosphere

    PubMed

    Toublanc, D; Parisot, J P; Brillet, J; Gautier, D; Raulin, F; McKay, C P

    1995-01-01

    We have developed a new photochemical model of Titan's atmosphere which includes all the important compounds and reactions in spherical geometry from the surface to 1240 km. Compared to the previous model of Yung et al. (1984, Astrophys. J. Suppl. 55, 465-506), the most significant recent change in the reactions used is the updated methane photodissociation scheme (Mordaunt et al. 1993, J. Chem. Phys. 98(3), 2054-2065). Moreover, the transfer of the solar radiation in the atmosphere and the photolysis rates have been calculated by using a Monte Carlo code. Finally, the eddy diffusion coefficient profile is adjusted in order to fit the mean vertical distribution of HCN retrieved from millimeter groundbased observations of Tanguy et al. (1990, Icarus, 85, 43-57) using new values for the boundary flux of atomic nitrogen (Strobel et al. 1992, Icarus 100, 512-526). We have run the model in both steady-state and diurnal modes, with 62 speices involved in 249 reactions. There is little difference between diurnal and steady-state results. Overall our results are in a closer agreement with the abundances inferred from the Voyager infrared measurements at the equator than the Yung et al. results. We find that the catalytic scheme for H recombination invoked by Yung et al. only slightly improves the model results and we conclude that this scheme is not essential to fit observations. PMID:11538950

  16. Export of arsenic from forested catchments under easing atmospheric pollution

    SciTech Connect

    Lucie Erbanova; Martin Novak; Daniela Fottova; Barbora Dousova

    2008-10-01

    Massive lignite burning in Central European power plants peaked in the 1980s. Dissolved arsenic in runoff from upland forest ecosystems is one of the ecotoxicological risks resulting from power plant emissions. Maxima in As concentrations in runoff from four forest catchments have increased 2-5 times between 1995 and 2006, and approach the drinking water limit (10 {mu}g L{sup -1}). To assess the fate of anthropogenic As, we constructed input/output mass balances for three polluted and one relatively unpolluted forest catchment in the Czech Republic, and evaluated the pool size of soil As. The observation period was 11 years, and the sites spanned a 6-fold As pollution gradient. Two of the polluted sites exhibit large net As export via runoff solutes (mean of 4-5 g As ha{sup -1} yr{sup -1} for the 11-year period; up to 28 g As ha{sup -1} yr{sup -1} in 2005). This contrasts with previous studies which concluded that forest catchments are a net sink for atmogenic arsenic both at times of increasing and decreasing pollution. The amount of exported As is not correlated with the total As soil pool size, which is over 78% geogenic in origin, but correlates closely with water fluxes via runoff. Net arsenic release is caused by an interplay of hydrological conditions and retreating acidification which may mobilize arsenic by competitive ligand exchange. The effects of droughts and other aspects of climate change on subsequent As release from soil were not investigated. Between-site comparisons indicate that most pollutant As may be released from humus. 24 refs., 7 figs., 1 tab.

  17. Method for protecting plant life from acidic atmospheric pollutants

    SciTech Connect

    Lengyel, A.D.

    1986-10-14

    A method is described for treating a stand of coniferous trees growing by natural processes and exposed to an atmosphere containing inorganic nitric acid or nitrate compounds to improve the resistance of the trees to damage by acid rain. The method consists of foliarly applying at least one sugar selected from the group consisting of monosaccharides and disaccharides to the coniferous trees naturally growing in the stand exposed to the atmosphere.

  18. AICE Survey of USSR Air Pollution Literature, Volume 12: Technical Papers from the Leningrad International Symposium on the Meteorological Aspects of Atmospheric Pollution, Part I.

    ERIC Educational Resources Information Center

    Nuttonson, M. Y.

    Twelve papers dealing with the meteorological aspects of air pollution were translated. These papers were initially presented at an international symposium held in Leningrad during July 1968. The papers are: Status and prospective development of meteorological studies of atmospheric pollution, Effect of the stability of the atmosphere on the…

  19. Detection of atmospheric pollutants by pulsed photoacoustic spectroscopy

    NASA Astrophysics Data System (ADS)

    Roman, Miruna; Pascu, Mihail-Lucian; Staicu, Angela

    1998-07-01

    Pulsed laser photoacoustic detection of NO2 and SO2 is reported. The laser source is a pulsed molecular nitrogen laser emitting at 337.1 nm. The average energy per pulse is about 350 (mu) J and the pulse duration 10 nsec. For detection we used a piezoelectric transducer (TUSIM-N.I.M.P., resonance frequency 4 MHz) and an electret condenser microphone (Trevi EM 27). The photoacoustic cell was a nonresonant one, with a cylindrical shape. The laser beam was centered along the cylinder axis. Linear dependence of the photoacoustic signal on pollutant pressure was obtained. This linearity is in a good agreement with theoretical considerations. The photoacoustic signal was measured for pollutants pressure between 1 torr and 100 torr for NO2 and between 35 torr and 100 torr for SO2.

  20. Effects of atmospheric pollutants on forests, wetlands, and agricultural ecosystems

    SciTech Connect

    Hutchinson, T.C.; Meema, K.M.

    1987-01-01

    This book reports on the knowledge of the sensitivities and responses of forests, wetlands and crops to airborne pollutants. Pollutants examined include: acidic depositions, heavy metal particulates, sulphur dioxide, ozone, nitrogen oxides, acid fogs, and mixtures of these. Various types of ecosystem stresses and physiological mechanisms pertinent to acid deposition are also discussed. Related subjects, such as the effects of ethylene on vegetation, the physiology of drought in trees, the ability of soils to generate acidity naturally, the role of Sphagnum moss in natural peatland acidity, the use of lichens as indicators of changing air quality, and the magnitude of natural emissions of reduced sulphur gases from tropical rainforests and temperate deciduous forests, are covered.

  1. Modeling pollutant transport using a meshless-lagrangian particle model

    SciTech Connect

    Carrington, D. B.; Pepper, D. W.

    2002-01-01

    A combined meshless-Lagrangian particle transport model is used to predict pollutant transport over irregular terrain. The numerical model for initializing the velocity field is based on a meshless approach utilizing multiquadrics established by Kansa. The Lagrangian particle transport technique uses a random walk procedure to depict the advection and dispersion of pollutants over any type of surface, including street and city canyons

  2. Spectral Optical Properties of the Polluted Atmosphere of Mexico City (Spring-Summer 1992)

    NASA Technical Reports Server (NTRS)

    Vasilyev, O. B.; Contreras, A. Leyva; Valazquez, A. Muhlia; Peralta-Fabi, R.; Ivlev, L. S.; Kovalenko, A. P.; Vasilyev, A. V.; Jukov, V. M.; Welch, Ronald M.

    1995-01-01

    A joint Mexican, Russian, and American research effort has been initiated to develop new methods to remotely sense atmospheric parameters using ground-based, aircraft, and satellite observations. As a first step in this program, ground-based spectrophotometric measurements of the direct solar radiation have been obtained for the extremely polluted Mexico City atmosphere for the period of April-June 1992. These observations were made at more than 1300 channels in the spectral range of 0.35-0.95 microns. In the UltraViolet (UV) portions of the spectrum (e.g., 0.35 microns), aerosol optical thicknesses were found to range between 0.6 and 1.2; in the visible portion of the spectrum (e. g., 0.5 microns) they ranged from 0.5 to 0.8; and in the Near-Infrared (NIR) spectra (e.g., 0.85 micron), values of 0.3 - 0.5 were found. Applying a Spectral Optical Depth (SOD) model of tau(lambda) = C + A(lambda(sup -varies as), values of 1.55 less than varies as less than 1.85 were obtained for polluted, cloudless days, with values of 1.25 less than varies as less than 1.60 on days with haze. The aerosol particles in the polluted Mexico City atmosphere were found to be strongly absorbing, with a single-scattering albedo of 0.7 - 0.9 in the UV, 0.6 - 0.8 in the visible portion of the spectrum, and 0.4 - 0.7 in the NIR. These values are possibly consistent with a high soot concentration, contributed both by vehicular traffic and heavy industry. Analysis of the measured aerosol SOD using the optical parameters of an urban aerosol model pemiits the concentration of aerosol particles to be estimated in the vertical column; a maximum value of 3 x 10(exp 9) 1/sq cm was found. This concentration of aerosol particles exceeds that found in most other regions of the globe by at least an order of magnitude. Near the ground the aerosol size distributions measured using an optical particle counter were found to be strongly multimodal.

  3. Atmospheric Dispersion Model Validation in Low Wind Conditions

    SciTech Connect

    Sawyer, Patrick

    2007-11-01

    Atmospheric plume dispersion models are used for a variety of purposes including emergency planning and response to hazardous material releases, determining force protection actions in the event of a Weapons of Mass Destruction (WMD) attack and for locating sources of pollution. This study provides a review of previous studies that examine the accuracy of atmospheric plume dispersion models for chemical releases. It considers the principles used to derive air dispersion plume models and looks at three specific models currently in use: Aerial Location of Hazardous Atmospheres (ALOHA), Emergency Prediction Information Code (EPIcode) and Second Order Closure Integrated Puff (SCIPUFF). Results from this study indicate over-prediction bias by the EPIcode and SCIPUFF models and under-prediction bias by the ALOHA model. The experiment parameters were for near field dispersion (less than 100 meters) in low wind speed conditions (less than 2 meters per second).

  4. Lithosphere - Atmosphere - Ionosphere Circuit Model

    NASA Astrophysics Data System (ADS)

    Kereselidze, Z.; Kachakhidze, N.; Kachakhidze, M.

    2012-04-01

    There are offered possibilities of original LAI circuit model. The problem concerns of existence of self-generated electromagnetic oscillations in the segment of LAI system, which are results of tectonic stress developing in the focus area of expected earthquake. By this model the main (lowest) frequency of these electromagnetic oscillations frequency spectrum is expressed analytically by following formula: ω = β c l where β(ω) is the coefficient depended on the frequency and geological characteristics of the medium and approximate to one, c-is the speed of light, and l- the length of the fault in the focus of the expected earthquake. On the base of relevant diagnosis of experimental data, the model gives us possibility to discuss the problem about location, time of occurrence and intensity of an expected earthquake with certain accuracy. In addition to it, considered model does not block the fall-unstable model of earthquake preparing and electromagnetic phenomena accompanied earthquake preparing process. On the contrary, the imagination of physical picture may be simplified in the separate stage of earthquakes preparing. Namely, it is possible to reliably separate series of foreshocks and aftershocks. By this point of view, the certain optimism about using of EM emission as earthquake precursor of full value may be expressed. The base of such optimism is developing of various phenomena connected to VLF emission many times fixed in the surroundings of epicentral area and cosmic space (changing of intensity of electro-telluric current, perturbations of geomagnetic field in forms of irregular pulsations or regular short-period pulsations, perturbations of atmospheric electric field, perturbations of ionosphere critical frequency and TEC, variations of height of lower ionosphere, parameters of ionospheric medium: changing of specific dielectric conductivity and spectrum of MGD waves in it, atmospheric-ionospheric discharging and etc.).

  5. Multiwavelength Modeling of Nova Atmospheres

    NASA Technical Reports Server (NTRS)

    Hauschildt, P. H.; Starrfield, S.

    1997-01-01

    We have analyzed the early optically thick ultraviolet spectra of Nova OS And 1986 using a grid of spherically symmetric, non-LTE, line-blanketed, expanding model atmospheres and synthetic spectra with the following set of parameters: 5,000 less than or equal to T(sub model) less than or equal to 60,000K, solar abundances, (rho)(alpha) r(sup -3), v(sub max) = 2000 km/s, L = 6 x 10(exp 4) solar luminosity, and a statistical or microturbulent velocity of 50 km/s. We used the synthetic spectra to estimate the model parameters corresponding to the observed IUE spectra. The fits to the observations were then iteratively improved by changing the parameters of the model atmospheres, in particular T(sub model) and the abundances, to arrive at the best fits to the optically thick pseudo-continuum and the features found in the IUE spectra. The IUE spectra show two different optically thick subphases. The earliest spectra, taken a few days after maximum optical light, show a pseudo-continuum created by overlapping absorption lines. The later observations, taken approximately 3 weeks after maximum light, show the simultaneous presence of allowed, semi-forbidden, and forbidden lines in the observed spectra. Analysis of these phases indicate that OS And 86 had solar metallicities except for Mg which showed evidence of being underabundant by as much as a factor of 10. We determine a distance of 5.1 kpc to OS And 86 and derive a peak bolometric luminosity of approximately 5 x 10(exp 4) solar luminosity. The computed nova parameters provide insights into the physics of the early outburst and explain the spectra seen by IUE. Lastly, we find evidence in the later observations for large non-LTE effects of Fe II which, when included, lead to much better agreement with the observations.

  6. Atmospheric pollutants in peri-urban forests of Quercus ilex: evidence of pollution abatement and threats for vegetation.

    PubMed

    García-Gómez, Héctor; Aguillaume, Laura; Izquieta-Rojano, Sheila; Valiño, Fernando; Àvila, Anna; Elustondo, David; Santamaría, Jesús M; Alastuey, Andrés; Calvete-Sogo, Héctor; González-Fernández, Ignacio; Alonso, Rocío

    2016-04-01

    Peri-urban vegetation is generally accepted as a significant remover of atmospheric pollutants, but it could also be threatened by these compounds, with origin in both urban and non-urban areas. To characterize the seasonal and geographical variation of pollutant concentrations and to improve the empirical understanding of the influence of Mediterranean broadleaf evergreen forests on air quality, four forests of Quercus ilex (three peri-urban and one remote) were monitored in different areas in Spain. Concentrations of nitrogen dioxide (NO2), ammonia (NH3), nitric acid (HNO3) and ozone (O3) were measured during 2 years in open areas and inside the forests and aerosols (PM10) were monitored in open areas during 1 year. Ozone was the only air pollutant expected to have direct phytotoxic effects on vegetation according to current thresholds for the protection of vegetation. The concentrations of N compounds were not high enough to directly affect vegetation but could be contributing through atmospheric N deposition to the eutrophization of these ecosystems. Peri-urban forests of Q. ilex showed a significant below-canopy reduction of gaseous concentrations (particularly NH3, with a mean reduction of 29-38%), which indicated the feasibility of these forests to provide an ecosystem service of air quality improvement. Well-designed monitoring programs are needed to further investigate air quality improvement by peri-urban ecosystems while assessing the threat that air pollution can pose to vegetation. PMID:26620865

  7. Atmospheric mercury pollution around a chlor-alkali plant in Flix (NE Spain): an integrated analysis.

    PubMed

    Esbrí, José M; López-Berdonces, Miguel Angel; Fernández-Calderón, Sergio; Higueras, Pablo; Díez, Sergi

    2015-04-01

    An integrated analysis approach has been applied to a mercury (Hg) case study on a chlor-alkali plant located in the Ebro River basin, close to the town of Flix (NE Spain). The study focused on atmospheric Hg and its incorporation in soils and lichens close to a mercury cell chlor-alkali plant (CAP), which has been operating since the end of the 19th century. Atmospheric Hg present in the area was characterized by means of seven total gaseous mercury (TGM) surveys carried out from 2007 to 2012. Surveys were carried out by car, walking, and at fixed locations, and covered an area of some 12 km(2) (including the CAP area, the village in which workers live, Flix town, and the Sebes Wildlife Reserve). Finally, an atmospheric Hg dispersion model was developed with ISC-AERMOD software validated by a lichen survey of the area. The results for the atmospheric compartment seem to indicate that the Flix area currently has the highest levels of Hg pollution in Spain on the basis of the extremely high average concentrations in the vicinity of the CAP (229 ng m(-3)). Moreover, the Hg(0) plume affects Flix town center to some extent, with values well above the international thresholds for residential areas. Wet and dry Hg deposition reached its highest values on the banks of the Ebro River, and this contributes to increased soil contamination (range 44-12,900 ng g(-1), average 775 ng g(-1)). A good fit was obtained between anomalous areas indicated by lichens and the dispersion model for 1 year. PMID:25035055

  8. An index for estimating the potential metal pollution contribution to atmospheric particulate matter from road dust in Beijing.

    PubMed

    Zhao, Hongtao; Shao, Yaping; Yin, Chengqing; Jiang, Yan; Li, Xuyong

    2016-04-15

    The resuspension of road dust from street surfaces could be a big contributor to atmospheric particulate pollution in the rapid urbanization context in the world. However, to date what its potential contribution to the spatial pattern is little known. Here we developed an innovative index model called the road dust index (RI<105μm) and it combines source and transport factors for road dust particles <105μm in diameter. It could quantify and differentiate the impact of the spatial distribution of the potential risks posed by metals associated with road dust on atmospheric suspended particles. The factors were ranked and weighted based on road dust characteristics (the amounts, grain sizes, and mobilities of the road dust, and the concentrations and toxicities of metals in the road dust). We then applied the RI<105μm in the Beijing region to assess the spatial distribution of the potential risks posed by metals associated with road dust on atmospheric suspended particles. The results demonstrated that the road dust in urban areas has higher potential risk of metal to atmospheric particles than that in rural areas. The RI<105μm method offers a new and useful tool for assessing the potential risks posed by metals associated with road dust on atmospheric suspended particles and for controlling atmospheric particulate pollution caused by road dust emissions. PMID:26815293

  9. A study of atmospheric diffusion from the LANDSAT imagery. [pollution transport over the ocean

    NASA Technical Reports Server (NTRS)

    Dejesusparada, N. (Principal Investigator); Viswanadham, Y.; Torsani, J. A.

    1981-01-01

    LANDSAT multispectral scanner data of the smoke plumes which originated in eastern Cabo Frio, Brazil and crossed over into the Atlantic Ocean, are analyzed to illustrate how high resolution LANDSAT imagery can aid meteorologists in evaluating specific air pollution events. The eleven LANDSAT images selected are for different months and years. The results show that diffusion is governed primarily by water and air temperature differences. With colder water, low level air is very stable and the vertical diffusion is minimal; but water warmer than the air induces vigorous diffusion. The applicability of three empirical methods for determining the horizontal eddy diffusivity coefficient in the Gaussian plume formula was evaluated with the estimated standard deviation of the crosswind distribution of material in the plume from the LANDSAT imagery. The vertical diffusion coefficient in stable conditions is estimated using Weinstock's formulation. These results form a data base for use in the development and validation of meso scale atmospheric diffusion models.

  10. The etymological role of the main atmosphere pollutants in development of human diseases.

    PubMed

    Lomtatidze, N; Kiknadze, N; Khakhnalidze, R; Tusishvili, Kh; Alasania, N; Kiknadze, M

    2013-04-01

    The aim of research was monitoring of the main atmospheric air pollutants concentration on Adjara Autonomous Republic territory in order to determine their role in causing different diseases. The following atmospheric air pollutants have been determined in Batumi: dust, carbon monoxide, sulfur and nitrogen dioxide. The number of diseases registered in Adjara Autonomous Republic, which may be linked to the air pollution, has been studied. These are the following: chronic and nonspecific bronchitis, asthma and asthma status diseases, allergic rhinitis, trachea-, bronchi- and lung malignant tumor. In order to reduce the number of risk-factors significant attention should be paid to the proper functionality of the vehicles and systematic observations should continue on the chemical pollution of the air to make proper decisions to reduce the number of diseases. PMID:23676494

  11. Is atmospheric phosphorus pollution altering global alpine Lake stoichiometry?

    NASA Astrophysics Data System (ADS)

    Brahney, Janice; Mahowald, Natalie; Ward, Daniel S.; Ballantyne, Ashley P.; Neff, Jason C.

    2015-09-01

    Anthropogenic activities have significantly altered atmospheric chemistry and changed the global mobility of key macronutrients. Here we show that contemporary global patterns in nitrogen (N) and phosphorus (P) emissions drive large hemispheric variation in precipitation chemistry. These global patterns of nutrient emission and deposition (N:P) are in turn closely reflected in the water chemistry of naturally oligotrophic lakes (r2 = 0.81, p < 0.0001). Observed increases in anthropogenic N deposition play a role in nutrient concentrations (r2 = 0.20, p < 0.05) however, atmospheric deposition of P appears to be major contributor to this pattern (r2 = 0.65, p < 0.0001). Atmospheric simulations indicate a global increase in P deposition by 1.4 times the preindustrial rate largely due to increased dust and biomass burning emissions. Although changes in the mass flux of global P deposition are smaller than for N, the impacts on primary productivity may be greater because, on average, one unit of increased P deposition has 16 times the influence of one unit of N deposition. These stoichiometric considerations, combined with the evidence presented here, suggest that increases in P deposition may be a major driver of alpine Lake trophic status, particularly in the Southern Hemisphere. These results underscore the need for the broader scientific community to consider the impact of atmospheric phosphorus deposition on the water quality of naturally oligotrophic lakes.

  12. Study of atmospheric pollution scavenging. Eighteenth progress report

    SciTech Connect

    Semonin, R.G.; Bartlett, J.D.; Bowersox, V.C.; Gatz, D.F.; Naiman, D.Q.; Peden, M.E.; Stahlhut, R.K.; Stensland, G.J.

    1980-07-01

    The analysis of aerosol samples obtained in rural east-central Illinois reveals a seasonal maximum in SO/sub 4/ during May to July and a similar pattern for NH/sub 4/. The annual median SO/sub 4/ is about 1 to 1.5 ..mu..g/m/sup 3/. In contrast to these ions, NO/sub 3/ displays highest values in the cold season. Soil-related species (Ca, K) seem to maximize in relation to farm tillage and harvesting practices. The NO/sub 3/ in recent precipitation samples over the northeast US increased between 1 and 2 times the values observed in the mid-1950's. A case study from SCORE-78 suggests that all ion concentrations analyzed from sequentially collected samples decreased from the onset of rain to a minimum corresponding to the heaviest rain rates. Four groups of elements in 10 event rain samples were identified using factor analysis. The groups include soluble and insoluble crustal elements, soluble pollutant metals and sulfate, and insoluble pollutant metals. Utilizing the factor analysis approach, the St. Louis METROMEX precipitation chemistry data showed that the SO/sub 4/ deposition patterns group consistently with those of other soluble pollutants. Additional factor analysis efforts on the St. Louis rainwater data set revealed that soluble and insoluble concentrations of a given element have different deposition patterns suggesting that scavenging and/or precipitation formation processes dictate the patterns. An approach to managing the vast data base of rain chemistry used in the above studies is described. The software also examines the data for certain aspects of quality assurance. The procedures used to analyze ambient air filter samples are discussed.

  13. Possible influence of atmospheric circulations on winter hazy pollution in Beijing-Tianjin-Hebei region, northern China

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Zhang, X.; Gong, D.; Kim, S.-J.; Mao, R.; Zhao, X.

    2015-08-01

    Using the daily records derived from the synoptic weather stations and the NCEP/NCAR and ERA-Interim reanalysis data, the variability of the winter hazy pollutions (indicated by the mean visibility and number of hazy days) in Beijing-Tianjin-Hebei (BTH) region during the period 1981 to 2015 and its relationship to the atmospheric circulations in middle-high latitude were analyzed in this study. The winter hazy pollution in BTH had distinct inter-annual and inter-decadal variabilities without a significant long-term trend. According to the spatial distribution of correlation coefficients, six atmospheric circulation indices (I1 to I6) were defined from the key areas in sea level pressure (SLP), zonal and meridional winds at 850 hPa (U850, V850), geopotential height field at 500 hPa (H500), zonal wind at 200 hPa (U200), and air temperature at 200 hPa (T200), respectively. All of the six indices have significant and stable correlations with the winter visibility and number of hazy days in BTH. Both the visibility and number of hazy days can be estimated well by using the six indices and fitting and the cross-validation with leave-N-out method, respectively. The high level of the prediction statistics and the reasonable mechanism suggested that the winter hazy pollutions in BTH can be forecasted or estimated credibly based on the optimized atmospheric circulation indices. However, we also noted that the statistic estimation models would be largely influenced by the artificial control of a pollutant discharge. Thus it is helpful for government decision-making departments to take actions in advance in dealing with probably severe hazy pollutions in BTH indicated by the atmospheric circulation conditions.

  14. Means of atmospheric air pollution reduction during drilling wells

    NASA Astrophysics Data System (ADS)

    Shkitsa, L.; Yatsyshyn, T.; Lyakh, M.; Sydorenko, O.

    2016-08-01

    The process of drilling oil and gas wells is the source of air pollution through drilling mud evaporation containing hazardous chemical substances. The constructive solution for cleaning device of downhole tool that contains elements covering tube and clean the surface from the mud in the process of rising from the well is offered. Inside the device is filled with magnetic fluid containing the substance neutralizing hazardous substances. The use of the equipment proposed will make it possible to avoid penetration of harmful substances into the environment and to escape the harmful effects of aggressive substances for staff health and increase rig's fire safety.

  15. Clean Air Slots Amid Dense Atmospheric Pollution in Southern Africa

    NASA Technical Reports Server (NTRS)

    Hobbs, Peter V.

    2003-01-01

    During the flights of the University of Washington's Convair-580 in the Southern African Regional Science Initiative (SAFARI 2000) in southern Africa, a phenomenon was observed that has not been reported previously. This was the occurrence of thin layers of remarkably clean air, sandwiched between heavily polluted air, which persisted for many hours during the day. Photographs are shown of these clean air slots (CAS), and particle concentrations and light scattering coefficients in and around such slot are presented. An explanation is proposed for the propensity of CAS to form in southern Africa during the dry season.

  16. Atmospheric transport and dispersion of pollutants and related meteorological studies. Progress report, FY 1982

    SciTech Connect

    Draxler, R.R.; Ferber, G.J.; Heffter, J.L.; Cordella, R.H. Jr.; Miller, J.M.

    1982-09-01

    Research emphasizes model simulation and experimental verification of the transport and dispersion of atmospheric pollutants. Field experiments of mechanisms affecting long-range transport which provide dispersion data for verification of regional and continental models are stressed. A multi-layer trajectory-dispersion model that incorporates the effects of wind shear was tested against long-range concentration data. Models for prognostic trajectory calculations, using wind fields, have been recoded to permit operational procedures on interactive terminals; and will be used in tracer experiments and emergencies. A new tracer system, using perfluorocarbons, has been developed to provide for long-range dispersion experiments and model validation studies. The tracer system was used in the DOE-ASCOT studies of nocturnal drainage flows in the Geysers geothermal development area. A long-range dispersion study, the Cross-Appalachian Tracer Experiments (CAPTEX) is planned. There will be a series of perfluorocarbon tracer releases in the Ohio Valley with tracer concentration measurements from Ohio to the East Coast. A trial run is planned for September 1982 and a full-scale program in the summer of 1983. A high voluem version of the automatic sequential sampler and an inexpensive adsorption tube sampler were developed. Another tracer experiment is being carried out in collaboration with the DOE Savnnah River Laboratory to provide long-term, regional-scale transport and diffusion data for air pollution model verification. Krypton-85, is sampled at five stations from 300 to 1000 km to the northeast. This one-year twice daily sampling program may be extended to 18 months.

  17. Investigating Nitrogen Pollution: Activities and Models.

    ERIC Educational Resources Information Center

    Green Teacher, 2000

    2000-01-01

    Introduces activities on nitrogen, nitrogen pollution from school commuters, nitrogen response in native and introduced species, and nutrient loading models. These activities help students determine the nitrogen contribution from their parents' cars, test native plant responses to nitrogen, and experiment with the results of removing water from…

  18. Integrated pollutant removal: modeling and experimentation

    SciTech Connect

    Ochs, Thomas L.; Oryshchyn, Danylo B.; Summers, Cathy A.

    2005-01-01

    Experimental and computational work at the Albany Research Center, USDOE is investigating an integrated pollutant removal (IPR) process which removes all pollutants from flue gas, including SOX, NOX, particulates, CO2, and Hg. In combination with flue gas recirculation, heat recovery, and oxy-fuel combustion, the process produces solid, gas, and liquid waste streams. The gas exhaust stream comprises O2 and N2. Liquid streams contain H2O, SOX, NOX, and CO2. Computer modeling and low to moderate pressure experimentation are defining system chemistry with respect to SOX and H2O as well as heat and mass transfer for the IPR process.

  19. Atmospheric Models for Mars Aerocapture

    NASA Technical Reports Server (NTRS)

    Justus, C. G.; Duvall, Aleta; Keller, Vernon W.

    2005-01-01

    level Mars atmospheric model. Applications include systems design, performance analysis, and operations planning for aerobraking, entry descent and landing, and aerocapture. Typical Mars aerocapture periapsis altitudes (for systems with rigid- aeroshell heat shields) are about 50 km. This altitude is above the 0-40 km height range covered by Mars Global Surveyor Thermal Emission Spectrometer (TES) nadir observations. Recently, TES limb sounding data have been made available, spanning more than two Mars years (more than 200,000 data profiles) with altitude coverage up to about 60 km, well within the height range of interest for aerocapture. Results are presented comparing Mars-GRAM atmospheric density with densities from TES nadir and limb sounding observations. A new Mars-GRAM feature is described which allows individual TES nadir or limb profiles to be extracted from the large TES databases, and to be used as an optional replacement for standard Mars-GRAM background (climatology) conditions. For Monte-Carlo applications such as aerocapture guidance and control studies, Mars-GRAM perturbations are available using these TES profile background conditions.

  20. Effect of typhoon on atmospheric aerosol particle pollutants accumulation over Xiamen, China.

    PubMed

    Yan, Jinpei; Chen, Liqi; Lin, Qi; Zhao, Shuhui; Zhang, Miming

    2016-09-01

    Great influence of typhoon on air quality has been confirmed, however, rare data especially high time resolved aerosol particle data could be used to establish the behavior of typhoon on air pollution. A single particle aerosol spectrometer (SPAMS) was employed to characterize the particles with particle number count in high time resolution for two typhoons of Soulik (2013) and Soudelor (2015) with similar tracks. Three periods with five events were classified during the whole observation time, including pre - typhoon (event 1 and event 2), typhoon (event 3 and event 4) and post - typhoon (event 5) based on the meteorological parameters and particle pollutant properties. First pollutant group appeared during pre-typhoon (event 2) with high relative contributions of V - Ni rich particles. Pollution from the ship emissions and accumulated by local processes with stagnant meteorological atmosphere dominated the formation of the pollutant group before typhoon. The second pollutant group was present during typhoon (event 3), while typhoon began to change the local wind direction and increase wind speed. Particle number count reached up to the maximum value. High relative contributions of V - Ni rich and dust particles with low value of NO3(-)/SO4(2-) was observed during this period, indicating that the pollutant group was governed by the combined effect of local pollutant emissions and long-term transports. The analysis of this study sheds a deep insight into understand the relationship between the air pollution and typhoon. PMID:27295441

  1. Atmospheric Models for Aeroentry and Aeroassist

    NASA Technical Reports Server (NTRS)

    Justus, C. G.; Duvall, Aleta; Keller, Vernon W.

    2004-01-01

    Eight destinations in the Solar System have sufficient atmosphere for aeroentry, aeroassist, or aerobraking/aerocapture: Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, plus Saturn's moon Titan. Engineering-level atmospheric models for Earth, Mars, Titan, and Neptune have been developed for use in NASA s systems analysis studies of aerocapture applications. Development has begun on a similar atmospheric model for Venus. An important capability of these models is simulation of quasi-random perturbations for Monte Carlo analyses in developing guidance, navigation and control algorithms, and for thermal systems design. Characteristics of these atmospheric models are compared, and example applications for aerocapture are presented. Recent Titan atmospheric model updates are discussed, in anticipation of applications for trajectory and atmospheric reconstruct of Huygens Probe entry at Titan. Recent and planned updates to the Mars atmospheric model, in support of future Mars aerocapture systems analysis studies, are also presented.

  2. Atmospheric Models for Aeroentry and Aeroassist

    NASA Technical Reports Server (NTRS)

    Justus, C. G.; Duvall, Aleta; Keller, Vernon W.

    2005-01-01

    Eight destinations in the Solar System have sufficient atmosphere for aeroentry, aeroassist, or aerobraking/aerocapture: Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, plus Saturn's moon Titan. Engineering-level atmospheric models for Earth, Mars, Titan, and Neptune have been developed for use in NASA's systems analysis studies of aerocapture applications. Development has begun on a similar atmospheric model for Venus. An important capability of these models is simulation of quasi-random perturbations for Monte Carlo analyses in developing guidance, navigation and control algorithms, and for thermal systems design. Characteristics of these atmospheric models are compared, and example applications for aerocapture are presented. Recent Titan atmospheric model updates are discussed, in anticipation of applications for trajectory and atmospheric reconstruct of Huygens Probe entry at Titan. Recent and planned updates to the Mars atmospheric model, in support of future Mars aerocapture systems analysis studies, are also presented.

  3. Study of atmospheric pollution scavenging. Twenty-fourth progress report

    SciTech Connect

    Williams, A.L.

    1990-08-01

    Atmospheric scavenging research conducted by the Illinois State Water Survey under contract with the Department of Energy has been a significant factor in the historical development of the field of precipitation scavenging. Emphasis of the work during the 1980`s became focused on the problem of acid rain problem with the Survey being chosen as the Central Analytical Laboratory for sample analysis of the National Atmospheric Deposition Program National Trends Network (NADP/NTN). The DOE research was responsible for laying the groundwork from the standpoint of sampling and chemical analysis that has now become routine features of NADP/NTN. A significant aspect of the research has been the participation by the Water Survey in the MAP3S precipitation sampling network which is totally supported by DOE, is the longest continuous precipitation sampling network in existence, and maintains an event sampling protocol. The following review consists of a short description of each of the papers appearing in the Study of Atmospheric Scavenging progress reports starting with the Eighteenth Progress Report in 1980 to the Twenty- Third Progress Report in 1989. In addition a listing of the significant publications and interviews associated with the program are given in the bibliography.

  4. Estimation of Biomass Burning Influence on Air Pollution around Beijing from an Aerosol Retrieval Model

    PubMed Central

    Mukai, Sonoyo; Nakata, Makiko

    2014-01-01

    We investigate heavy haze episodes (with dense concentrations of atmospheric aerosols) occurring around Beijing in June, when serious air pollution was detected by both satellite and ground measurements. Aerosol retrieval is achieved by radiative transfer simulation in an Earth atmosphere model. We solve the radiative transfer problem in the case of haze episodes by successive order of scattering. We conclude that air pollution around Beijing in June is mainly due to increased emissions of anthropogenic aerosols and that carbonaceous aerosols from agriculture biomass burning in Southeast Asia also contribute to pollution. PMID:25250383

  5. The washout effects of rainfall on atmospheric particulate pollution in two Chinese cities.

    PubMed

    Guo, Ling-Chuan; Zhang, Yonghui; Lin, Hualiang; Zeng, Weilin; Liu, Tao; Xiao, Jianpeng; Rutherford, Shannon; You, Jing; Ma, Wenjun

    2016-08-01

    Though rainfall is recognized as one of the main mechanisms to reduce atmospheric particulate pollution, few studies have quantified this effect, particularly the corresponding lag effect and threshold. This study aimed to investigate the association between rainfall and air quality using a distributed lag non-linear model. Daily data on ambient PM2.5 and PM2.5-10 (particulate matter with an aerodynamic diameter less than 2.5 μm and from 2.5 to 10 μm) and meteorological factors were collected in Guangzhou and Xi'an from 2013 to 2014. A better washout effect was found for PM2.5-10 than for PM2.5, and the rainfall thresholds for both particle fractions were 7 mm in Guangzhou and 1 mm in Xi'an. The decrease in PM2.5 levels following rain lasted for 3 and 6 days in Guangzhou and Xi'an, respectively. Rainfall had a better washout effect in Xi'an compared with that in Guangzhou. Findings from this study contribute to a better understanding of the washout effects of rainfall on particulate pollution, which may help to understand the category and sustainability of dust-haze and enforce anthropogenic control measures in time. PMID:27203467

  6. An evaluation of atmospheric Nr pollution and deposition in North China after the Beijing Olympics

    NASA Astrophysics Data System (ADS)

    Luo, X. S.; Liu, P.; Tang, A. H.; Liu, J. Y.; Zong, X. Y.; Zhang, Q.; Kou, C. L.; Zhang, L. J.; Fowler, D.; Fangmeier, A.; Christie, P.; Zhang, F. S.; Liu, X. J.

    2013-08-01

    North China is known for its large population densities and rapid development of industry and agriculture. Air quality around Beijing improved substantially during the 2008 Summer Olympics. We measured atmospheric concentrations of various Nr compounds at three urban sites and three rural sites in North China from 2010 to 2012 and estimated N dry and wet deposition by inferential models and the rain gauge method to determine current air conditions with respect to reactive nitrogen (Nr) compounds and nitrogen (N) deposition in Beijing and the surrounding area. NH3, NO2, and HNO3 and particulate NH4+ and NO3-, and NH4+-N and NO3--N in precipitation averaged 8.2, 11.5, 1.6, 8.2 and 4.6 μg N m-3, and 2.9 and 1.9 mg N L-1, respectively, with large seasonal and spatial variability. Atmospheric Nr (especially oxidized N) concentrations were highest at urban sites. Dry deposition of Nr ranged from 35.2 to 60.0 kg N ha-1 yr-1, with wet deposition of Nr of 16.3 to 43.2 kg N ha-1 yr-1 and total deposition of 54.4-103.2 kg N ha-1 yr-1. The rates of Nr dry and wet deposition were 36.4 and 33.2% higher, respectively, at the urban sites than at the rural sites. These high levels reflect the occurrence of a wide range of Nr pollution in North China and suggest that further strict air pollution control measures are required.

  7. Assessing the polycyclic aromatic hydrocarbon (PAH) pollution of urban stormwater runoff: a dynamic modeling approach.

    PubMed

    Zheng, Yi; Lin, Zhongrong; Li, Hao; Ge, Yan; Zhang, Wei; Ye, Youbin; Wang, Xuejun

    2014-05-15

    Urban stormwater runoff delivers a significant amount of polycyclic aromatic hydrocarbons (PAHs), mostly of atmospheric origin, to receiving water bodies. The PAH pollution of urban stormwater runoff poses serious risk to aquatic life and human health, but has been overlooked by environmental modeling and management. This study proposed a dynamic modeling approach for assessing the PAH pollution and its associated environmental risk. A variable time-step model was developed to simulate the continuous cycles of pollutant buildup and washoff. To reflect the complex interaction among different environmental media (i.e. atmosphere, dust and stormwater), the dependence of the pollution level on antecedent weather conditions was investigated and embodied in the model. Long-term simulations of the model can be efficiently performed, and probabilistic features of the pollution level and its risk can be easily determined. The applicability of this approach and its value to environmental management was demonstrated by a case study in Beijing, China. The results showed that Beijing's PAH pollution of road runoff is relatively severe, and its associated risk exhibits notable seasonal variation. The current sweeping practice is effective in mitigating the pollution, but the effectiveness is both weather-dependent and compound-dependent. The proposed modeling approach can help identify critical timing and major pollutants for monitoring, assessing and controlling efforts to be focused on. The approach is extendable to other urban areas, as well as to other contaminants with similar fate and transport as PAHs. PMID:24631618

  8. Theory and modeling of stellar atmospheres

    NASA Astrophysics Data System (ADS)

    Hubeny, Ivan

    2010-08-01

    I will briefly outline basic concepts of the stellar atmospheres theory. After summarizing basic structural equations describing a stellar atmospheres, an emphasis is given to describing efficient numerical methods developed to deal with the stellar atmosphere problem, namely the method of complete linearization ant its recent variants, and the whole class of methods known by name Accelerated Lambda Iteration. In the next part of the lectures I will briefly summarize existing computer codes, with an emphasis on our code TLUSTY, and list some of the most useful grids of model atmospheres that are publicly available. Next, I will show how the model atmospheres and synthetic spectra are used in quantitative stellar spectroscopy in order to determine basic stellar parameters and chemical abundances. Finally, I will briefly describe an application of model atmosphere theory and models to related objects, such as accretion disks around various accretors, and atmospheres of substellar-mass objects-extrasolar giant planets and brown dwarfs.

  9. Titan atmosphere models, 1973. [Saturn satellite

    NASA Technical Reports Server (NTRS)

    Divine, N.

    1974-01-01

    The composition and structure of the atmosphere of Titan, based on theory and on spectroscopic and infrared data, is reviewed for the development of numerical engineering models. Light, nominal, and heavy atmospheres are described and tabulated, and their profiles of radius, temperature, pressure, and density are illustrated. Corresponding descriptions of atmospheric dynamics, condensates and surfaces are outlined.

  10. POINTS-OF-CONTACT (ATMOSPHERIC PROTECTION BRANCH, AIR POLLUTION PREVENTION AND CONTROL DIVISION, NRMRL)

    EPA Science Inventory

    The Atmospheric Protection Branch's (APB's) Points-of-Contact page lists APB's research areas along with the name, phone number and e-mail address of the responsible person. APB is part of NRMRL's Air Pollution Prevention and Control Division in Research Triangle Park, NC. The ...

  11. The laser absorption spectrometer - A new remote sensing instrument for atmospheric pollution monitoring

    NASA Technical Reports Server (NTRS)

    Shumate, M. S.

    1974-01-01

    An instrument capable of remotely monitoring trace atmospheric constituents is described. The instrument, called a laser absorption spectrometer, can be operated from an aircraft or spacecraft to measure the concentration of selected gases in three dimensions. This device will be particularly useful for rapid determination of pollutant levels in urban areas.

  12. Critical Evaluation of Air-Liquid Interface Exposure Devices for In Vitro Assessment of Atmospheric Pollutants

    EPA Science Inventory

    Exposure of cells to atmospheric pollutants at the air-liquid interface (ALI) is a more realistic approach than exposures of attached cells submerged in liquid medium. However, there is still limited understanding of the ideal ALI device design features that permit reproducible a...

  13. ASSESSMENT OF CROP LOSS FROM AIR POLLUTANTS: METEOROLOGY-ATMOSPHERIC CHEMISTRY AND LONG RANGE TRANSPORT

    EPA Science Inventory

    Ozone is a secondary pollutant with many distinctive characteristics in respect to its sources and modes of formation within regions of the troposphere and in the stratosphere. The scales of intermediate and longer range transport influencing the atmospheric distribution of O3 wi...

  14. Laser systems for stand-off detection of contamination and pollution of atmosphere

    NASA Astrophysics Data System (ADS)

    Mierczyk, Zygmunt

    2007-02-01

    The paper presents selected laser systems used for remote detection of contamination and pollution of atmosphere. Having in view a way of taking samples for analysis, the methods used for atmosphere monitoring can be divided into two groups: sampling at the place of existing pollution and remote detection, identification, and measurement of concentration. "Stand-off" and "remote" systems of atmosphere monitoring are described here. The "stand-off" systems provide detection of pollution (gas, aerosol, smoke, dust) at long distances, without the contact with a contaminated area. These systems are active laser systems (lidars) or passive thermal systems with narrow filters matched to the bands of gas absorption and imaging the transmission changes of radiation absorbed along the path of gas presence. A single "stand-off" station can cover significant area, the size of which depends on the range of sampling radiation, field of view, and scanning speed. "Remote" systems employ various types of small point sensors and the data from these sensors are transmitted by wire or wireless connections to alarm centres. It should be pointed out that in this case, a contact between sensor and analysed area is necessary and remote detection is performed by the transmission systems of measurement data. The paper presents construction, principle of operation, and basic analytical characteristics of the chosen "standoff" and "remote" measuring systems developed at Military University of Technology, devoted to continuous monitoring of contaminations and pollution of atmosphere.

  15. Atmospheric pollution in an urban environment by tree bark biomonitoring--part I: trace element analysis.

    PubMed

    Guéguen, Florence; Stille, Peter; Lahd Geagea, Majdi; Boutin, René

    2012-03-01

    Tree bark has been shown to be a useful biomonitor of past air quality because it accumulates atmospheric particulate matter (PM) in its outermost structure. Trace element concentrations of tree bark of more than 73 trees allow to elucidate the impact of past atmospheric pollution on the urban environment of the cities of Strasbourg and Kehl in the Rhine Valley. Compared to the upper continental crust (UCC) tree barks are strongly enriched in Mn, Ni, Cu, Zn, Cd and Pb. To assess the degree of pollution of the different sites in the cities, a geoaccumulation index I(geo) was applied. Global pollution by V, Ni, Cr, Sb, Sn and Pb was observed in barks sampled close to traffic axes. Cr, Mo, Cd pollution principally occurred in the industrial area. A total geoaccumulation index I(GEO-tot) was defined; it is based on the total of the investigated elements and allows to evaluate the global pollution of the studied environment by assembling the I(geo) indices on a pollution map. PMID:22169208

  16. Gas-aerosol partitioning of semi volatile carbonyls in polluted atmosphere in Hachioji, Tokyo

    NASA Astrophysics Data System (ADS)

    Matsunaga, Sou N.; Kato, Shungo; Yoshino, Ayako; Greenberg, Jim P.; Kajii, Yoshizumi; Guenther, Alex B.

    2005-06-01

    Gaseous and particulate semi volatile carbonyls have been measured in urban air using an annular denuder sampling system. Three dicarbonyls, five aliphatic aldehydes and two hydroxy carbonyls were observed. Concentrations of other biogenic and anthropogenic volatile organic compounds (VOCs), SO2, CO, NO2 and particle concentration were also measured. Estimated gas-aerosol equilibrium constants for the carbonyls showed an inverse correlation with the concentrations of anthropogenic pollutants such as benzene, isopentane and SO2. This suggests that the increase in the fraction of non-polar anthropogenic particles in the atmosphere could change the average property of the ambient aerosols and drive the gas particle equilibrium of the carbonyls to the gas phase. This trend is uncommon in remote forest air. In this study, we examined the factors controlling the equilibrium in the polluted atmosphere and show that there is a difference in gas-aerosol partition between polluted and clean air.

  17. Atmospheric transport of pollutants from North America to the North Atlantic Ocean

    NASA Technical Reports Server (NTRS)

    Harriss, R. C.; Browell, E. V.; Sebacher, D. I.; Gregory, G. L.; Hinton, R. R.; Beck, S. M.; Mcdougal, D. S.; Shipley, S. T.

    1984-01-01

    Ground-based measurements strongly support the hypothesis that pollutant materials of anthropogenic origin are being transported over long distances in the midtroposphere and are a significant source of acid rain, acid snow, trace metal deposition, ozone and visibility-reducing aerosols in remote oceanic and polar regions of the Norhern Hemisphere. Atmospheric sulphur budget calculations and studies of acid rain on Bermuda indicate that a large fraction of pollutant materials emitted into the atmosphere in eastern North America are advected eastwards over the North Atlantic Ocean. The first direct airborne measurements of the vertical distribution of tropospheric aerosols over the western North Atlantic is reported here. A newly developed airborne differential adsorption lidar system was used to obtain continuous, remotely sensed aerosol distributions along its flight path. The data document two episodes of long-distance transport of pollutant materials from North America over the North Atlantic Ocean.

  18. Composition of atmospheric suspensions of Ussuriisk City according to snow pollution

    NASA Astrophysics Data System (ADS)

    Golokhvast, Kirill S.; Soboleva, Elena V.; Borisovsky, Andrey O.; Khristoforova, Nadezhda K.

    2014-11-01

    The results of the study by scanning electron microscopy with energy dispersive analysis of microparticles of atmospheric suspensions contained in Ussuriysk winter snows (2012/2013) are presented. Particles of rocks and technogenic (mainly metal and soot) formations to prevail in the atmospheric suspensions of Ussuriysk are shown. There is a large amount of metal particles of automobile and industrial - Fe, Au, Pt, Pd, Cu, Sn, Pb, Ti, W. The analysis of the qualitative composition of atmospheric suspensions Ussuriysk confirms its status as a city with a strong impact of automobile transportation and high levels of air pollution.

  19. Trajectory Software With Upper Atmosphere Model

    NASA Technical Reports Server (NTRS)

    Barrett, Charles

    2012-01-01

    The Trajectory Software Applications 6.0 for the Dec Alpha platform has an implementation of the Jacchia-Lineberry Upper Atmosphere Density Model used in the Mission Control Center for International Space Station support. Previous trajectory software required an upper atmosphere to support atmosphere drag calculations in the Mission Control Center. The Functional operation will differ depending on the end-use of the module. In general, the calling routine will use function-calling arguments to specify input to the processor. The atmosphere model will then compute and return atmospheric density at the time of interest.

  20. The medieval metal industry was the cradle of modern large-scale atmospheric lead pollution in northern Europe

    SciTech Connect

    Braennvall, M.L.; Bindler, R.; Renberg, I.; Emteryd, O.; Bartnicki, J.; Billstroem, K.

    1999-12-15

    There is great concern for contamination of sensitive ecosystems in high latitudes by long-range transport of heavy metals and other pollutants derived from industrial areas in lower latitudes. Atmospheric pollution of heavy metals has a very long history, and since metals accumulate in the environment, understanding of present-day pollution conditions requires knowledge of past atmospheric deposition. The authors use analyses of lead concentrations and stable lead isotopes ({sup 206}Pb/{sup 207}Pb ratios) of annually laminated sediments from four lakes in northern Sweden to provide a decadal record of atmospheric lead pollution for the last 3000 years. There is a clear signal in the sediments of airborne pollution from Greek and Roman cultures 2000 years ago, followed by a period of clean conditions 400--900 A.D. From 900 A.D. there was a conspicuous, permanent increase in atmospheric lead pollution fallout, The sediments reveal peaks in atmospheric lead pollution at 1200 and 1530 A.D. comparable to present-day levels. These peaks match the history of metal production in Europe. This study indicates that the contemporary atmospheric pollution climate in northern Europe was established in Medieval time, rather than in the industrial period. Atmospheric lead pollution deposition did not, when seen in a historical perspective, increase as much as usually assumed with the Industrial Revolution.

  1. The IPAC-NC field campaign: a pollution and oxidization pool in the lower atmosphere over Huabei, China

    NASA Astrophysics Data System (ADS)

    Ma, J. Z.; Wang, W.; Chen, Y.; Liu, H. J.; Yan, P.; Ding, G. A.; Wang, M. L.; Sun, J.; Lelieveld, J.

    2012-05-01

    In the past decades, regional air pollution characterized by photochemical smog and grey haze-fog has become a severe environmental problem in China. To investigate this, a field measurement campaign was performed in the Huabei region, located between 32-42° N latitude in eastern China, during the period 2 April-16 May 2006 as part of the project "Influence of Pollution on Aerosols and Cloud Microphysics in North China" (IPAC-NC). It appeared that strong pollution emissions from urban and industrial centers tend to accumulate in the lower atmosphere over the central area of Huabei. We observed widespread, very high SO2 mixing ratios, about 20-40 ppbv at 0.5-1.5 km altitude and 10-30 ppbv at 1.5-3.0 km altitude. Average CO mixing ratios were 0.65-0.7 ppmv at 0.5-1.5 km altitude, and very high CO around 1 ppmv was observed during some flights, and even higher levels at the surface. We find the high pollution concentrations to be associated with enhanced levels of OH and HO2 radicals, calculated with a chemical box model constrained by the measurements. In the upper part of the boundary layer and in the lower free troposphere, high CO and SO2 compete with relatively less NO2 in reacting with OH, being efficiently recycled through HO2, preventing a net loss of HOx radicals. In addition to reactive hydrocarbons and CO, the oxidation of SO2 causes significant ozone production over Huabei (up to ~13% or 2.0 ppbv h-1 at 0.8 km altitude). Our results indicate that the lower atmosphere over Huabei is not only strongly polluted but also acts as an oxidation pool, with pollutants undergoing very active photochemistry over this part of China.

  2. Uncertainty characterization and quantification in air pollution models. Application to the ADMS-Urban model.

    NASA Astrophysics Data System (ADS)

    Debry, E.; Malherbe, L.; Schillinger, C.; Bessagnet, B.; Rouil, L.

    2009-04-01

    Evaluation of human exposure to atmospheric pollution usually requires the knowledge of pollutants concentrations in ambient air. In the framework of PAISA project, which studies the influence of socio-economical status on relationships between air pollution and short term health effects, the concentrations of gas and particle pollutants are computed over Strasbourg with the ADMS-Urban model. As for any modeling result, simulated concentrations come with uncertainties which have to be characterized and quantified. There are several sources of uncertainties related to input data and parameters, i.e. fields used to execute the model like meteorological fields, boundary conditions and emissions, related to the model formulation because of incomplete or inaccurate treatment of dynamical and chemical processes, and inherent to the stochastic behavior of atmosphere and human activities [1]. Our aim is here to assess the uncertainties of the simulated concentrations with respect to input data and model parameters. In this scope the first step consisted in bringing out the input data and model parameters that contribute most effectively to space and time variability of predicted concentrations. Concentrations of several pollutants were simulated for two months in winter 2004 and two months in summer 2004 over five areas of Strasbourg. The sensitivity analysis shows the dominating influence of boundary conditions and emissions. Among model parameters, the roughness and Monin-Obukhov lengths appear to have non neglectable local effects. Dry deposition is also an important dynamic process. The second step of the characterization and quantification of uncertainties consists in attributing a probability distribution to each input data and model parameter and in propagating the joint distribution of all data and parameters into the model so as to associate a probability distribution to the modeled concentrations. Several analytical and numerical methods exist to perform an

  3. Inorganic nitrogenous air pollutants, atmospheric nitrogen deposition and their potential ecological impacts in remote areas of western North America (Invited)

    NASA Astrophysics Data System (ADS)

    Bytnerowicz, A.; Fenn, M. E.; Fraczek, W.; Johnson, R.; Allen, E. B.

    2013-12-01

    Dry deposition of gaseous inorganic nitrogenous (N) air pollutants plays an important role in total atmospheric N deposition and its ecological effects in the arid and semi-arid ecosystems. Passive samplers and denuder/ filter pack systems have been used for determining ambient concentrations of ammonia (NH3), nitric oxide (NO), nitrogen dioxide (NO2), and nitric acid vapor (HNO3) in the topographically complex remote areas of the western United States and Canada. Concentrations of the measured pollutants varied significantly between the monitoring areas. Highest NH3, NO2 and HNO3 levels occurred in southern California areas downwind of the Los Angeles Basin and in the western Sierra Nevada impacted by emissions from the California Central Valley and the San Francisco Bay area. Strong spatial gradients of N pollutants were also present in southeastern Alaska due to cruise ship emissions and in the Athabasca Oil Sands Region in Canada affected by oil exploitation. Distribution of these pollutants has been depicted by maps generated by several geostatistical methodologies within the ArcGIS Geostatistical Analyst (ESRI, USA). Such maps help to understand spatial and temporal changes of air pollutants caused by various anthropogenic activities and locally-generated vs. long range-transported air pollutants. Pollution distribution maps for individual N species and gaseous inorganic reactive nitrogen (Nr) have been developed for the southern portion of the Sierra Nevada, Lake Tahoe Basin, San Bernardino Mountains, Joshua Tree National Park and the Athabasca Oil Sands Region. The N air pollution data have been utilized for estimates of dry and total N deposition by a GIS-based inferential method specifically developed for understanding potential ecological impacts in arid and semi-arid areas. The method is based on spatial and temporal distribution of concentrations of major drivers of N dry deposition, their surface deposition velocities and stomatal conductance values

  4. Seasonal comparison of moss bag technique against vertical snow samples for monitoring atmospheric pollution.

    PubMed

    Salo, Hanna; Berisha, Anna-Kaisa; Mäkinen, Joni

    2016-03-01

    This is the first study seasonally applying Sphagnum papillosum moss bags and vertical snow samples for monitoring atmospheric pollution. Moss bags, exposed in January, were collected together with snow samples by early March 2012 near the Harjavalta Industrial Park in southwest Finland. Magnetic, chemical, scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), K-means clustering, and Tomlinson pollution load index (PLI) data showed parallel spatial trends of pollution dispersal for both materials. Results strengthen previous findings that concentrate and slag handling activities were important (dust) emission sources while the impact from Cu-Ni smelter's pipe remained secondary at closer distances. Statistically significant correlations existed between the variables of snow and moss bags. As a summary, both methods work well for sampling and are efficient pollutant accumulators. Moss bags can be used also in winter conditions and they provide more homogeneous and better controlled sampling method than snow samples. PMID:26969058

  5. Effects of point-source atmospheric pollution on boreal-forest vegetation of northwestern Siberia

    SciTech Connect

    Vlasova, T.M.; Kovalev, B.I.; Filipchuk, A.N.

    1992-03-01

    Atmospheric pollution from the Noril'sk Mining-Metallurgical Complex, in the form of heavy metals and sulfur components, has resulted in damage to plant communities in the area. Vegetation on over 550,000 ha has been detrimentally affected by the pollution fallout, primarily sulfur dioxide. Forests (mainly Larix sibirica) and most lichens have been killed within a 300,000-ha zone around Noril'sk and extending about 50 km to the south and southeast. Less severe damage to lichens and vascular plants extends 170 km to the south and 80 km to the east of the pollution source consistent with prevailing winds during the period of plant growth. Terricolous lichens are particularly vulnerable to the pollution products and among vascular plants Larix gmelinii, Picea obovata, Ledum palustre, Calamagrostis sp., and Salix lanata show least resistance.

  6. Heavy pollution suppresses light rain in China: observations and modeling

    SciTech Connect

    Qian, Yun; Gong, Daoyi; Fan, Jiwen; Leung, Lai R.; Bennartz, Ralph; Chen, Deliang; Wang, Weiguo

    2009-08-15

    Long-term observational data reveal that both the frequency and amount of light rain have decreased in eastern China (EC) for 1956-2005 with high spatial coherency. This is different from the trend of total rainfall observed in EC, which decreases in northern EC and increases in southern EC. To examine the cause of the light rain trends, we analyzed the long-term variability of atmospheric water vapor and its correlation with light rain events. Results show very weak relationships between large-scale moisture transport and light rain in EC. This suggests that light rain trend in EC is not driven by large-scale circulation changes. Because of human activities, pollutant emission has increased dramatically in China for the last few decades, leading to significant reductions in visibility between 1960 and 2000. Cloud-resolving model simulations show that aerosols corresponding to heavily polluted conditions can significantly increase the cloud droplet number concentration (CDNC) and reduce droplet sizes compared to pristine conditions. This can lead to a significant decline in raindrop concentration and delay raindrop formation because smaller cloud droplets are less efficient in the collision and coalescence processes. Together with weaker convection, the precipitation frequency and amount are significantly reduced in the polluted case. Satellite data also reveal higher CDNC and smaller droplet size over polluted land in EC relative to pristine regions, which is consistent with the model results. This evidence suggests that the significantly increased aerosol particles produced by air pollution are at least partly responsible for the decreased light rain events observed in China over the past fifty years.

  7. Transboundary air pollution in Asia: Model development and policy implications

    NASA Astrophysics Data System (ADS)

    Holloway, Tracey

    2001-12-01

    This work investigates transboundary air pollution in Asia through atmospheric modeling and public policy analysis. As an example of models actively shaping environmental policy, the Convention on Long-Range Transboundary Air Pollution in Europe (LRTAP) is selected as a case study. The LRTAP Convention is the only mulit- lateral air pollution agreement to date, and results from the RAINS integrated assessment model were heavily used to calculate nationally differentiated emission ceilings. Atmospheric chemistry and transport are included in RAINS through the use of transfer coefficients (or ``source-receptor relationships'') relating pollutant transfer among European nations. Following past work with ATMOS to simulate sulfur species in Asia, here ATMOS is developed to include odd-nitrogen. Fitting with the linear structure of ATMOS and the emphasis on computational efficiency, a simplified chemical scheme developed for use in the NOAA Geophysical Fluid Dynamics Laboratory Global Chemical Transport Model (GFDL GCTM) is adopted. The method solves for the interconversions between NOx, HNO3, and PAN based on five reaction rates stored in look-up tables. ATMOS is used to calculate source-receptor relationships for Asia. Significant exchange of NOy occurs among China, North and South Korea, and Japan. On an annual average basis, China contributes 18% to Japan's total nitrate deposition, 46% to North Korea, and 26% to South Korea. Nitrate deposition is an important component of acidification (along with sulfate deposition), contributing 30-50% to the acid burden over most of Japan, and more than 50% to acid deposition in southeast Asia, where biomass burning emits high levels of NOx. In evaluating the policy-relevance of results from the ATMOS model, four factors are taken into account: the uncertainty and limitations of ATMOS, the environmental concerns facing Asia, the current status of the scientific community in relation to regional air pollution in the region, and

  8. Particle size effect for metal pollution analysis of atmospherically deposited dust

    NASA Astrophysics Data System (ADS)

    Al-Rajhi, M. A.; Al-Shayeb, S. M.; Seaward, M. R. D.; Edwards, H. G. M.

    The metallic compositions of 231 atmospherically deposited dust samples obtained from widely-differing environments in Riyadh city, Saudi Arabia, have been investigated in relation to the particle size distributions. Sample data are presented which show that particle size classification is very important when analysing dust samples for atmospheric metal pollution studies. By cross-correlation and comparison, it was found that the best way to express the results of the metal concentration trend was as an average of particle ratios. Correlations between the six metals studied, namely Pb, Cr, Ni, Cu, Zn and Li, were found for every particle size (eight categories) and reveal that the metal concentrations increased as the particle size decreased. On the basis of this work, it is strongly recommended that future international standards for metal pollutants in atmospherically deposited dusts should be based on particle size fractions.

  9. Variation of atmospheric air pollution under conditions of rapid economic change—Estonia 1994-1999

    NASA Astrophysics Data System (ADS)

    Kimmel, V.; Tammet, H.; Truuts, T.

    Estonia is an example of a country with economy in transition whose atmospheric air pollution has been remarkably influenced by economic changes. During the period of 1994-1999 GDP increased by one-fourth, while agricultural production, electricity and heat production dropped by one-sixths during the studied period. These processes are reflected in the quantity of emissions and structure of air pollution. The study is based on the measurements of concentrations of pollutants at six Estonian Euroairnet monitoring stations—at three sites in the capital city and at three sites in remote areas. The pollutants concerned are the first-priority pollutants in the European Union legislation—nitrogen oxides, SO 2, O 3, particulate matter, and additionally CO. The study reveals that concentrations of gaseous pollutants in Estonia remain within the EU limit values except for ozone in remote areas. The main trend during the studied period was a significant, up to several times, decrease in concentrations of SO 2 and CO while the decrease of nitrogen oxides was less remarkable. The paper propose ratio of NO x/SO 2 as an index describing increasing transport loads and drop in use of sulphur-rich fuels—thus of structure of economy. The annual variation of pollutants is explained by seasonal variations of anthropogenic activity in conditions where local fuels are widely used for heating during winter. Air pollution in Estonian rural stations mostly originated from transboundary fluxes. The 1-3 day delay of the weekly minimum of pollutant concentrations and the wind roses allow to conclude that essential part of pollutants is imported from West Europe.

  10. Modeling air pollution in the Tracking and Analysis Framework (TAF)

    SciTech Connect

    Shannon, J.D.

    1998-12-31

    The Tracking and Analysis Framework (TAF) is a set of interactive computer models for integrated assessment of the Acid Rain Provisions (Title IV) of the 1990 Clean Air Act Amendments. TAF is designed to execute in minutes on a personal computer, thereby making it feasible for a researcher or policy analyst to examine quickly the effects of alternate modeling assumptions or policy scenarios. Because the development of TAF involves researchers in many different disciplines, TAF has been given a modular structure. In most cases, the modules contain reduced-form models that are based on more complete models exercised off-line. The structure of TAF as of December 1996 is shown. Both the Atmospheric Pathways Module produce estimates for regional air pollution variables.

  11. Optical models of the molecular atmosphere

    NASA Technical Reports Server (NTRS)

    Zuev, V. E.; Makushkin, Y. S.; Mitsel, A. A.; Ponomarev, Y. N.; Rudenko, V. P.; Firsov, K. M.

    1986-01-01

    The use of optical and laser methods for performing atmospheric investigations has stimulated the development of the optical models of the atmosphere. The principles of constructing the optical models of molecular atmosphere for radiation with different spectral composition (wideband, narrowband, and monochromatic) are considered in the case of linear and nonlinear absorptions. The example of the development of a system which provides for the modeling of the processes of optical-wave energy transfer in the atmosphere is presented. Its physical foundations, structure, programming software, and functioning were considered.

  12. INTEGRATED AIR POLLUTION CONTROL SYSTEM (IAPCS) COST MODEL (AIR POLLUTION TECHNOLOGY BRANCH, AIR POLLUTION PREVENTION AND CONTROL DIVISION, NRMRL)

    EPA Science Inventory

    The Air Pollution Technology Branch's (APPCD, NRMRL) Integrated Air Pollution Control System Cost Model is a compiled model written in FORTRAN and C language that is designed to be used on an IBM or compatible PC with 640K or lower RAM and at least 1.5 Mb of hard drive space. It ...

  13. Source reconciliation of atmospheric gas-phase and particle-phase pollutants during a severe photochemical smog episode.

    PubMed

    Schauer, James J; Fraser, Matthew P; Cass, Glen R; Simoneit, Bernd R T

    2002-09-01

    A comprehensive organic compound-based receptor model is developed that can simultaneously apportion the source contributions to atmospheric gas-phase organic compounds, semivolatile organic compounds, fine particle organic compounds, and fine particle mass. The model is applied to ambient data collected at four sites in the south coast region of California during a severe summertime photochemical smog episode, where the model determines the direct primary contributions to atmospheric pollutants from 11 distinct air pollution source types. The 11 sources included in the model are gasoline-powered motor vehicle exhaust, diesel engine exhaust, whole gasoline vapors, gasoline headspace vapors, organic solvent vapors, whole diesel fuel, paved road dust, tire wear debris, meat cooking exhaust, natural gas leakage, and vegetative detritus. Gasoline engine exhaust plus whole gasoline vapors are the predominant sources of volatile organic gases, while gasoline and diesel engine exhaust plus diesel fuel vapors dominate the emissions of semivolatile organic compounds from these sources during the episode studied at all four air monitoring sites. The atmospheric fine particle organic compound mass was composed of noticeable contributions from gasoline-powered motor vehicle exhaust, diesel engine exhaust, meat cooking, and paved road dust with smaller but quantifiable contributions from vegetative detritus and tire wear debris. In addition, secondary organic aerosol, which is formed from the low-vapor pressure products of gas-phase chemical reactions, is found to be a major source of fine particle organic compound mass under the severe photochemical smog conditions studied here. The concentrations of secondary organic aerosol calculated in the present study are compared with previous fine particle source apportionment results for less intense photochemical smog conditions. It is shown that estimated secondary organic aerosol concentrations correlate fairly well with the

  14. Modeling pollutant dispersion within a tornadic thunderstorm

    SciTech Connect

    Pepper, D.W.

    1981-01-01

    A three-dimensional numerical model was developed to calculate ground-level air concentration and deposition of particles entrained in a tornadic thunderstorm. The rotational characteristics of the tornadic storm are within the larger mesoscale flow of the storm system and transported with the vortex. Turbulence exchange coefficients are based on empirical values. The quasi-Lagrangian method of moments is used to model the transport of concentration within a grid cell volume. Results indicate that updrafts and downdrafts, coupled with scavenging of particles by precipitation, account for most of the material being deposited closer to the site than anticipated. Approximately 5% of the pollutant is dispersed into the stratosphere.

  15. Development of mathematical techniques for the assimilation of remote sensing data into atmospheric models

    NASA Technical Reports Server (NTRS)

    Seinfeld, J. H. (Principal Investigator)

    1982-01-01

    The problem of the assimilation of remote sensing data into mathematical models of atmospheric pollutant species was investigated. The problem is posed in terms of the matching of spatially integrated species burden measurements to the predicted three dimensional concentration fields from atmospheric diffusion models. General conditions are derived for the "reconstructability' of atmospheric concentration distributions from data typical of remote sensing applications, and a computational algorithm (filter) for the processing of remote sensing data is developed.

  16. Development of mathematical techniques for the assimilation of remote sensing data into atmospheric models

    NASA Technical Reports Server (NTRS)

    Seinfeld, J. H. (Principal Investigator)

    1982-01-01

    The problem of the assimilation of remote sensing data into mathematical models of atmospheric pollutant species was investigated. The data assimilation problem is posed in terms of the matching of spatially integrated species burden measurements to the predicted three-dimensional concentration fields from atmospheric diffusion models. General conditions were derived for the reconstructability of atmospheric concentration distributions from data typical of remote sensing applications, and a computational algorithm (filter) for the processing of remote sensing data was developed.

  17. Polybromobenzene pollutants in the atmosphere of North China: levels, distribution, and sources.

    PubMed

    Lin, Yan; Qiu, Xinghua; Zhao, Yifan; Ma, Jin; Yang, Qiaoyun; Zhu, Tong

    2013-11-19

    Brominated flame retardants (BFRs) are important persistent organic pollutants. Analysis of BFRs in atmospheric samples in a previous study led us to suspect the presence of unidentified organic bromides, other than polybrominated diphenyl ethers (PBDEs), in the atmosphere. In this study, we identified and quantified polybromobenzenes, a group of organic bromides, in air samples collected through passive sampling in gridded observations in North China. We investigated their concentrations and spatial distribution, and estimated the proportion due to different sources. We detected seven species of polybromobenzenes, including hexabromobenzene (HBB), pentabromotoluene (PBT), pentabromoethylbenzene (PBEB), pentabromobenzene (PeBB), tetrabromobenzenes (TeBBs), and tribromotoluene (TrBT), in all or most of the field samples, indicating widespread occurrence of this class of pollutants. The median concentrations of each pollutant ranged from 20.0 to 144 pg/sample (or from 0.07 to 1.16 pg/m(3)), with relatively high concentrations found near e-waste recycling sites, BFR manufacturing sites, and areas of high population density. Positive matrix factorization (PMF) analysis revealed that ∼70% of HBB, PBT, PBEB, and PeBB was from commercial products, while ∼80% of 1,2,3,5-TeBB, 1,2,4,5-TeBB, and 2,4,5-TrBT was linked with BFR manufacturing. This study provides essential information on widespread polybromobenzene pollutants in the atmosphere, particularly TeBBs and TrBT, for which this is the first report of their presence as atmospheric pollutants. PMID:24144297

  18. Performance Engineering in the Community Atmosphere Model

    SciTech Connect

    Worley, P; Mirin, A; Drake, J; Sawyer, W

    2006-05-30

    The Community Atmosphere Model (CAM) is the atmospheric component of the Community Climate System Model (CCSM) and is the primary consumer of computer resources in typical CCSM simulations. Performance engineering has been an important aspect of CAM development throughout its existence. This paper briefly summarizes these efforts and their impacts over the past five years.

  19. Some results of CO and aerosols atmospheric pollution investigations in Moscow and Beijing

    NASA Astrophysics Data System (ADS)

    Rakitin, Vadim; Wang, Gengchen; Wang, Pusai; Grechko, Evgeny; Dzhola, Anatoly; Emilenko, Alexander; Fokeeva, Ekaterina; Kopeikin, Vladimir; Safronov, Alexander

    2014-05-01

    Results of the CO total column (TC) and submicron (sbm) and soot concentrations measurements in Moscow and Beijing for period from 1992 to 2013 years are presented. The rate of decrease of CO TC Moscow anthropogenic portion is 1.4 % per year for 1992-2013 years in spite of multiple increase of the motor vehicles number. There are no significant changes in CO TC over Beijing for whole period of measurements (1992-2013 years). Soot concentration in Beijing has decreased while sbm aerosol has increased since 2006 year. Level of atmospheric CO and aerosols pollution in Beijing is 2-5 times stronger in comparison with Moscow ones. Reasonably typical of atmospheric pollution events for Beijing with extreme values of CO TC and aerosols concentrations were observed in Moscow during wild fires of 2002 and 2010 years only. Trajectory cluster analysis using has allowed studying the location of sources of CO and aerosols emissions. Relatively stronger atmospheric pollution of Beijing partially due to the atmospheric transportation from industry regions of China located to south, south-east and east from the city.

  20. Accurate astronomical atmospheric dispersion models in ZEMAX

    NASA Astrophysics Data System (ADS)

    Spanò, P.

    2014-07-01

    ZEMAX provides a standard built-in atmospheric model to simulate atmospheric refraction and dispersion. This model has been compared with other ones to assess its intrinsic accuracy, critical for very demanding application like ADCs for AO-assisted extremely large telescopes. A revised simple model, based on updated published data of the air refractivity, is proposed by using the "Gradient 5" surface of Zemax. At large zenith angles (65 deg), discrepancies up to 100 mas in the differential refraction are expected near the UV atmospheric transmission cutoff. When high-accuracy modeling is required, the latter model should be preferred.

  1. Assessment of the spatial and temporal distribution of persistent organic pollutants (POPs) in the Nordic atmosphere

    NASA Astrophysics Data System (ADS)

    Anttila, Pia; Brorström-Lundén, Eva; Hansson, Katarina; Hakola, Hannele; Vestenius, Mika

    2016-09-01

    Long-term atmospheric monitoring data (1994-2011) of persistent organic pollutants (POPs) were assembled from a rural site in southern Sweden, Råö, and a remote, sub-Arctic site in Finland, Pallas. The concentration levels, congener profiles, seasonal and temporal trends, and projections were evaluated in order to assess the status of POPs in the Scandinavian atmosphere. Our data include atmospheric concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs), altogether comprising a selection of 27 different compounds. The atmospheric POP levels were generally higher in the south, closer to the sources (primary emissions) of the pollutants. The levels of low-chlorinated PCBs and chlordanes were equal at the two sites, and one of the studied POPs, α-HCH, showed higher levels in the north than in the south. Declining temporal trends in the atmospheric concentrations for the legacy POPs - PCBs (2-4% per year), HCHs (6-7% per year), chlordanes (3-4% per year) and DTTs (2-5% per year) - were identified both along Sweden's west coast and in the sub-Arctic area of northern Finland. Most of PAHs did not show any significant long-term trends. The future projections for POP concentrations suggest that in Scandinavia, low-chlorinated PCBs and p,p‧-DDE will remain in the atmospheric compartment the longest (beyond 2030). HCH's and PCB180 will be depleted from the Nordic atmosphere first, before 2020, whereas chlordanes and rest of the PCBs will be depleted between the years 2020 and 2025. PCBs tend to deplete sooner and chlordanes later from the sub-Arctic compared to the south of Sweden. This study demonstrates that the international bans on legacy POPs have successfully reduced the concentrations of these particular substances in the Nordic atmosphere. However, the most long-lived compounds may continue in the atmospheric cycle for another couple of decades.

  2. Comparison of laser methods for the remote detection of atmospheric pollutants.

    NASA Technical Reports Server (NTRS)

    Kildal, H.; Byer, R. L.

    1971-01-01

    Three methods of remote air pollution detection - Raman backscattering, resonance backscattering, and resonance absorption - are discussed and compared. Theoretical expressions are derived for the minimum detectable pollutant concentration, and in each case the depth resolution and the problems of interference, pump depletion, and background noise are discussed. A brief discussion of possible laser sources is included, numerical examples of the detectabilities based on present technology are given. The atmospheric transparency limits the useful range to a few kilometers for the Raman and resonance backscattering schemes. F or the resonance absorption technique the useful range can be as great as 50 kilometers.

  3. The Role of Urban Landscape Green in Urban Atmospheric Pollution Prevention

    NASA Astrophysics Data System (ADS)

    Wang, S. Y.; Kong, H.

    Through the investigation to understand the different nature of the city, the scale of the different planning and design, different varieties of seedlings of different plant configurations, different green hard landscape materials and air quality within the respective plots, find out toxic and harmful substances in the atmosphere absorb absorption, resistance stagnation, degradation of the strongest, least amount of dust generated dust, improving urban air quality best green landscape design, ideas and principles, and thus adjust and optimize the urban landscape, the landscape green purifying improve urban air quality, improve the urban environment repair of air pollution, urban centers in urban air pollution prevention role.

  4. USER'S GUIDE FOR PEM-2: POLLUTION EPISODIC MODEL (VERSION 2)

    EPA Science Inventory

    The Pollution Episodic Model Version 2 (PEM-2) is an urban-scale model designed to predict short term average ground-level concentrations and deposition fluxes of one or two gaseous or particulate pollutants at multiple receptors. The two pollutants may be non-reactive, or chemic...

  5. Modeling pollutant penetration across building envelopes

    SciTech Connect

    Liu, De-Ling; Nazaroff, William W.

    2001-04-01

    As air infiltrates through unintentional openings in building envelopes, pollutants may interact with adjacent surfaces. Such interactions can alter human exposure to air pollutants of outdoor origin. We present modeling explorations of the proportion of particles and reactive gases (e.g., ozone) that penetrate building envelopes as air enters through cracks and wall cavities. Calculations were performed for idealized rectangular cracks, assuming regular geometry, smooth inner crack surface and steady airflow. Particles of 0.1-1.0 {micro}m diameter are predicted to have the highest penetration efficiency, nearly unity for crack heights of 0.25 mm or larger, assuming a pressure difference of 4 Pa or greater and a flow path length of 3 cm or less. Supermicron and ultrafine particles are significantly removed by means of gravitational settling and Brownian diffusion, respectively. In addition to crack geometry, ozone penetration depends on its reactivity with crack surfaces, as parameterized by the reaction probability. For reaction probabilities less than {approx}10{sup -5}, penetration is complete for cracks heights greater than 1 mm. However, penetration through mm scale cracks is small if the reaction probability is {approx}10{sup -4} or greater. For wall cavities, fiberglass insulation is an efficient particle filter, but particles would penetrate efficiently through uninsulated wall cavities or through insulated cavities with significant airflow bypass. The ozone reaction probability on fiberglass fibers was measured to be 10{sup -7} for fibers previously exposed to high ozone levels and 6 x 10{sup -6} for unexposed fibers. Over this range, ozone penetration through fiberglass insulation would vary from >90% to {approx}10-40%. Thus, under many conditions penetration is high; however, there are realistic circumstances in which building envelopes can provide substantial pollutant removal. Not enough is yet known about the detailed nature of pollutant penetration

  6. Concentrations and δ13C values of atmospheric CO2 from oceanic atmosphere through time: polluted and non-polluted areas

    NASA Astrophysics Data System (ADS)

    Longinelli, Antonio; Lenaz, Renzo; Ori, Carlo; Selmo, Enrico

    2005-11-01

    CO2 is one of the primary agents of global climate changes. The increase of atmospheric CO2 concentration is essentially related to human-induced emissions and, particularly, to the burning of fossil fuel whose δ13C values are quite negative. Consequently, an increase of the CO2 concentration in the atmosphere should be paralleled by a decrease of its δ13C. Continuous and/or spot measurements of CO2 concentrations were repeatedly carried out during the last decade and in the same period of the year along hemispheric courses from Italy to Antarctica on a vessel of the Italian National Research Program in Antarctica. During these expeditions, discrete air samples were also collected in 4-l Pyrex flasks in order to carry out precise carbon isotope analyses on atmospheric CO2 from different areas, including theoretically 'clean' open ocean areas, with the main purpose of comparing these open ocean results with the results obtained by the National Oceanic and Atmospheric Administration/World Meteorological Organization (NOAA/WMO) at land-based stations. According to the data obtained for these two variables, a relatively large atmospheric pollution is apparent in the Mediterranean area where the CO2 concentration has reached the value of 384 ppmv while quite negative δ13C values have been measured only occasionally. In this area, southerly winds probably help to reduce the effect of atmospheric pollution even though, despite a large variability of CO2 concentrations, these values are consistently higher than those measured in open ocean areas by a few ppmv to about 10 ppmv. A marked, though non-continuous, pollution is apparent in the area of the Bab-el-Mandeb strait where δ13C values considerably more negative than in the Central and Southern Red Sea were measured. The concentration of atmospheric CO2 over the Central Indian Ocean increased from about 361 ppmv at the end of 1996 to about 373 ppmv at the end of 2003 (mean growth rate of about 1.7 ppmv yr

  7. Modelling of air pollution on a military airfield

    NASA Astrophysics Data System (ADS)

    Brzozowski, Krzysztof; Kotlarz, Wojciech

    The paper presents a numerical study of exhaust emission and pollutant dispersion of carbon monoxide on a military airfield. Investigations have been carried out for typical conditions of aircraft usage in the Polish Air Force Academy in Dęblin. Two different types of aircraft have been taken into account. One of them is an MI-2 helicopter, the second is a TS-11 plane. Both are used in military pilot education in Poland. Exhaust emission of CO from those aircrafts has been obtained in an experiment carried out on an engine test stand. CO concentrations have been calculated for different meteorological conditions (averaged from 5 years observations) and selected conditions of aircraft use. The finite volume method has been used to discretise the equation describing the process of pollutant dispersion. In addition, the two-cycle decomposition method has been employed to solve the set of ordinary differential equations of the first order obtained after discretisation of the advection-diffusion equation. A meteorological pre-processor, based on relationships resulting from the Monin-Obukhov theory, is used to define eddy diffusivity and the profile of air speed in the lower layer of the atmosphere. In the paper, the computer model and calculated average concentration of CO in the Dęblin airfield during typical flights are presented. The goal of the computational analysis is to predict CO pollution level in the workplace of aircraft service personnel.

  8. Moisture dynamics in the cloudy and polluted tropical atmosphere: The Cloud Aerosol Radiative Forcing Dynamics Experiment (CARDEX)

    NASA Astrophysics Data System (ADS)

    Wilcox, E. M.; Thomas, R. M.; Praveen, P. S.; Pistone, K.; Bender, F.; Feng, Y.; Ramanathan, V.

    2012-12-01

    Aerosols are well known to modify the microphysical properties of clouds. This modification is expected to yield brighter clouds that cover a greater area. However, observations from satellites show little inter-hemispheric difference in cloud optical thickness and liquid water path in spite of the clear inter-hemispheric difference in aerosol optical thickness. Furthermore, comparisons of observations with global atmospheric models suggest that models that parameterize the mechanisms of aerosol nucleation of cloud drops but do not resolve cloud-scale dynamics may be overestimating the magnitude of aerosol effects on cloud radiative forcing. Resolving these discrepancies requires a deeper understanding of the factors determining the transport of moisture to the cloud layer and the effects of aerosols on that transport. Towards this goal, we have conducted a new field experiment to study the moisture dynamics in the boundary layer and lower troposphere of the polluted and cloudy tropical atmosphere. The Cloud Aerosol Radiative Forcing Dynamics Experiment (CARDEX) was conducted during the winter of 2012 at the Maldives Climate Observatory - Hanimaadhoo in the tropical northern Indian Ocean during the period of extensive outflow of the South Asian pollution. Pollution in the CARDEX region has been well documented to both modify the microphysical properties of low clouds and strongly absorb solar radiation with significant consequences for the lower atmosphere and surface radiative energy budgets. Three unmanned aerial vehicles (UAVs) flew nearly 60 research flights instrumented to measure turbulent latent and sensible heat fluxes, aerosol concentrations, and cloud microphysical properties. Airborne measurements were enhanced with continuous surface monitoring of surface turbulent heat fluxes, aerosol concentrations and physical properties, surface remote sensing of cloud water amount and aerosol profiles, and model analyses of aerosols and dynamics with WRFchem. This

  9. Influence of meteorological parameters on particulates and atmospheric pollutants at Taichung harbor sampling site.

    PubMed

    Fang, Guor-Cheng; Wu, Yuh-Shen; Wen, Chih-Chung; Lee, Wen-Jhy; Chang, Shih-Yu

    2007-05-01

    Atmospheric aerosol particles and metallic concentrations, ionic species were monitored at the Experimental harbor of Taichung sampling site in this study. This work attempted to characterize metallic elements and ionic species associated with meteorological conditions variation on atmospheric particulate matter in TSP, PM2.5, PM2.5-10. The concentration distribution trend between TSP, PM2.5, PM2.5-10 particle concentration at the TH (Taichung harbor) sampling site were also displayed in this study. Besides, the meteorological conditions variation of metallic elements (Fe, Mg, Cr, Cu, Zn, Mn and Pb) and ions species (Cl(-), NO3 (-), SO4 (2-), NH4+, Mg2+, Ca2+ and Na+) concentrations attached with those particulate were also analyzed in this study. On non-parametric (Spearman) correlation analysis, the results indicated that the meteorological conditions have high correlation at largest particulate concentrations for TSP at TH sampling site in this study. In addition, the temperature and relative humidity of meteorological conditions that played a key role to affect particulate matter (PM) and have higher correlations then other meteorological conditions such as wind speed and atmospheric pressure. The parameter temperature and relative humidity also have high correlations with atmospheric pollutants compared with those of the other meteorological variables (wind speed, atmospheric pressure and prevalent wind direction). In addition, relative statistical equations between pollutants and meteorological variables were also characterized in this study. PMID:17057996

  10. [Pollution characteristics and health risk assessment of atmospheric volatile organic compounds (VOCs) in pesticide factory].

    PubMed

    Tan, Bing; Wang, Tie-Yu; Pang, Bo; Zhu, Zhao-Yun; Wang, Dao-Han; Lü, Yong-Long

    2013-12-01

    A method for determining volatile organic compounds (VOCs) in air by summa canister collecting and gas chromatography/ mass spectroscopy detecting was adopted. Pollution condition and characteristics of VOCs were discussed in three representative pesticide factories in Zhangjiakou City, Hebei Province. Meanwhile, an internationally recognized four-step evaluation model of health risk assessment was applied to preliminarily assess the health risk caused by atmospheric VOCs in different exposure ways, inhalation and dermal exposure. Results showed that serious total VOCs pollution existed in all factories. Concentrations of n-hexane (6161.90-6910.00 microg x m(-3)), benzene (126.00-179.30 microg x m(-3)) and 1,3-butadiene (115.00-177.30 microg x m(-3)) exceeded the Chronic Inhalation Reference Concentrations recommended by USEPA, corresponding to 700, 30 and 2 microg x m(-3), respectively. Concentration of dichloromethane (724.00 microg x m(-3)) in factory B was also higher than the reference concentration (600 microg x m(-3)). Results of health risk assessment indicated that non-carcinogenic risk indexes of VOCs ranged from 1.00E-04 to 1.00E + 00 by inhalation exposure, and 1.00E-09 to 1.00E-05 by dermal exposure. Risk indexes of n-hexane and dichloromethane by inhalation exposure in all factories exceeded 1, and risk index of benzene by inhalation in factory B was also higher than 1. Carcinogenic risk indexes exposed to VOCs ranged from 1.00E-08 to 1.00E-03 by inhalation exposure and 1. oo00E -13 to 1.00E-08 by dermal exposure. Cancer risk of 1,3-butadiene by inhalation exceeded 1.0E-04, which lead to definite risk, and those of benzene by inhalation also exceeded the maximum allowable level recommended by International Commission on Radiological Protection (5.0E-05). The risks of dermal exposure presented the same trend as inhalation exposure, but the level was much lower than that of inhalation exposure. Thus, inhalation exposure of atmospheric VOCs was the