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. Atmospheric pollution

    SciTech Connect

    Schlesinger, R.B. )

    1992-06-01

    Air pollution has been directly responsible for increases in mortality and morbidity in the general population during periods known as episodes, when pollutant levels were elevated well above those that occur on a regular basis. The major concern today regarding pollution and health is, however, more subtle--namely, whether the lower levels of pollution to which we are exposed daily are harmful to health. It is extremely difficult to relate specific health problems to specific pollutants, because other environmental and lifestyle factors may contribute to decrements in health. Furthermore, people are generally exposed to mixtures of pollutants, making it difficult to extract the effects caused by individual components, or to determine which combinations are the most hazardous. Community air pollution results from various sources: mobile sources, such as vehicles; stationary sources, such as power plants and factories; and indoor sources, such as building material. Complicating the picture is the fact that many chemicals released into the air may react, producing additional secondary pollutants. This article provides an overview of the major air pollutants that may be of concern in terms of public health.

  3. Atmospheric pollution.

    PubMed

    Schlesinger, R B

    1992-06-01

    Air pollution has been directly responsible for increases in mortality and morbidity in the general population during periods known as episodes, when pollutant levels were elevated well above those that occur on a regular basis. The major concern today regarding pollution and health is, however, more subtle--namely, whether the lower levels of pollution to which we are exposed daily are harmful to health. It is extremely difficult to relate specific health problems to specific pollutants, because other environmental and lifestyle factors may contribute to decrements in health. Furthermore, people are generally exposed to mixtures of pollutants, making it difficult to extract the effects caused by individual components, or to determine which combinations are the most hazardous. Community air pollution results from various sources: mobile sources, such as vehicles; stationary sources, such as power plants and factories; and indoor sources, such as building material. Complicating the picture is the fact that many chemicals released into the air may react, producing additional secondary pollutants. This article provides an overview of the major air pollutants that may be of concern in terms of public health.

  4. Geoinformation modeling system for analysis of atmosphere pollution impact on vegetable biosystems using space images

    NASA Astrophysics Data System (ADS)

    Polichtchouk, Yuri; Ryukhko, Viatcheslav; Tokareva, Olga; Alexeeva, Mary

    2002-02-01

    Geoinformation modeling system structure for assessment of the environmental impact of atmospheric pollution on forest- swamp ecosystems of West Siberia is considered. Complex approach to the assessment of man-caused impact based on the combination of sanitary-hygienic and landscape-geochemical approaches is reported. Methodical problems of analysis of atmosphere pollution impact on vegetable biosystems using geoinformation systems and remote sensing data are developed. Landscape structure of oil production territories in southern part of West Siberia are determined on base of processing of space images from spaceborn Resource-O. Particularities of atmosphere pollution zones modeling caused by gas burning in torches in territories of oil fields are considered. For instance, a pollution zones were revealed modeling of contaminants dispersal in atmosphere by standard model. Polluted landscapes areas are calculated depending on oil production volume. It is shown calculated data is well approximated by polynomial models.

  5. 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)

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. On the modeling of atmospheric pollutant dispersion during a diurnal cycle: A finite element study

    NASA Astrophysics Data System (ADS)

    Albani, Roseane A. S.; Duda, Fernando P.; Pimentel, Luiz Cláudio G.

    2015-10-01

    In this paper, we present a numerical model to study pollutant dispersion in the atmospheric boundary layer (ABL). The model accounts for the mechanisms of advection by the mean wind in the horizontal direction, turbulent diffusion in the vertical direction to ground surface, dry deposition, and radioactive decay. More importantly, the model is capable of accounting for the evolution of the ABL structure over a diurnal cycle by considering parameterizations for the wind-speed and eddy-diffusivity profiles that depend on the atmospheric stability condition, which in turn undergoes dramatic changes throughout the day. To solve the resulting advection-diffusion equation, we propose a numerical method based on a stabilized finite element formulation. After validating the numerical model by simulating classical experiments and comparing its predictions with those available in literature, we study the dispersion of a pollutant during a full diurnal ABL cycle with the meteorological parameters generated by AERMET for a 24-h period on a 1-h basis.

  12. 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.

  13. Impact of two chemistry mechanisms fully coupled with mesoscale model on the atmospheric pollutants distribution

    NASA Astrophysics Data System (ADS)

    Arteta, J.; Cautenet, S.; Taghavi, M.; Audiffren, N.

    Air quality models (AQM) consist of many modules (meteorology, emission, chemistry, deposition), and in some conditions such as: vicinity of clouds or aerosols plumes, complex local circulations (mountains, sea breezes), fully coupled models (online method) are necessary. In order to study the impact of lumped chemical mechanisms in AQM simulations, we examine the ability of both different chemical mechanisms: (i) simplified: Condensed Version of the MOdèle de Chimie Atmosphérique 2.2 (CV-MOCA2.2), and (ii) reference: Regional Atmospheric Chemistry Model (RACM), which are coupled online with the Regional Atmospheric Modeling Systems (RAMS) model, on the distribution of pollutants. During the ESCOMPTE experiment (Expérience sur Site pour COntraindre les Modèles de Pollution et de Transport d'Emissions) conducted over Southern France (including urban and industrial zones), Intensive observation periods (IOP) characterized by various meteorological and mixed chemical conditions are simulated. For both configurations of modeling, numerical results are compared with surface measurements (75 stations) for primary (NO x) and secondary (O 3) species. We point out the impact of the two different chemical mechanisms on the production of species involved in the oxidizing capacity such as ozone and radicals within urban and industrial areas. We highlight that both chemical mechanisms produce very similar results for the main pollutants (NO x and O 3) in three-dimensional (3D) distribution, despite large discrepancies in 0D modeling. For ozone concentration, we found sometimes small differences (5-10 ppb) between the mechanisms under study according to the cases (polluted or not). The relative difference between the two mechanisms over the whole domain is only -7% for ozone from CV-MOCA 2.2 versus RACM. When the order of magnitude is needed rather than an accurate estimate, a reduced mechanism is satisfactory. It has the advantage of running faster (four times less than CPU

  14. 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.

  15. 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

  16. 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.

  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. 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.

  19. 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

  20. 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

  1. 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.

  2. 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.

  3. Megacities and atmospheric pollution.

    PubMed

    Molina, Mario J; Molina, Luisa T

    2004-06-01

    About half of the world's population now lives in urban areas because of the opportunity for a better quality of life. Many of these urban centers are expanding rapidly, leading to the growth of megacities, which are defined as metropolitan areas with populations exceeding 10 million inhabitants. These concentrations of people and activity are exerting increasing stress on the natural environment, with impacts at urban, regional and global levels. In recent decades, air pollution has become one of the most important problems of megacities. Initially, the main air pollutants of concern were sulfur compounds, which were generated mostly by burning coal. Today, photochemical smog--induced primarily from traffic, but also from industrial activities, power generation, and solvents--has become the main source of concern for air quality, while sulfur is still a major problem in many cities of the developing world. Air pollution has serious impacts on public health, causes urban and regional haze, and has the potential to contribute significantly to climate change. Yet, with appropriate planning, megacities can efficiently address their air quality problems through measures such as application of new emission control technologies and development of mass transit systems. This review is focused on nine urban centers, chosen as case studies to assess air quality from distinct perspectives: from cities in the industrialized nations to cities in the developing world. While each city--its problems, resources, and outlook--is unique, the need for a holistic approach to the complex environmental problems is the same. There is no single strategy in reducing air pollution in megacities; a mix of policy measures will be needed to improve air quality. Experience shows that strong political will coupled with public dialog is essential to effectively implement the regulations required to address air quality problems.

  4. 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

  5. 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.

  6. United States: Canada memorandum of intent on transboundary air pollution. Atmospheric modeling, Work Group 2

    SciTech Connect

    Machta, L.

    1981-03-01

    The transport of air pollution from their sources to final deposition was investigated. Depositions in sensitive ecological areas are outlined. Several models were developed in both Canada and the U.S. for application in long range transport studies. The models describe sulfur deposition on an annual basis. A transfer matrix is adopted to establish a quantitative relationship between pollution emission and deposition in sensitive areas.

  7. Atmospheric Chemistry and Air Pollution

    DOE PAGES

    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

  8. Atmospheric chemistry and air pollution.

    PubMed

    Gaffney, Jeffrey S; Marley, Nancy A

    2003-04-07

    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 ozone 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.

  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. 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.

  11. 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

  12. Integrated assessment modeling of atmospheric pollutants in the Southern Appalachian Mountains. Part I: hourly and seasonal ozone.

    PubMed

    Boylan, James W; Odman, Mehmet T; Wilkinson, James G; Russell, Armistead G; Doty, Kevin G; Norris, William B; McNider, Richard T

    2005-07-01

    Recently, a comprehensive air quality modeling system was developed as part of the Southern Appalachians Mountains Initiative (SAMI) with the ability to simulate meteorology, emissions, ozone, size- and composition-resolved particulate matter, and pollutant deposition fluxes. As part of SAMI, the RAMS/EMS-95/URM-1ATM modeling system was used to evaluate potential emission control strategies to reduce atmospheric pollutant levels at Class I areas located in the Southern Appalachians Mountains. This article discusses the details of the ozone model performance and the methodology that was used to scale discrete episodic pollutant levels to seasonal and annual averages. The daily mean normalized bias and error for 1-hr and 8-hr ozone were within U.S. Environment Protection Agency guidance criteria for urban-scale modeling. The model typically showed a systematic overestimation for low ozone levels and an underestimation for high levels. Because SAMI was primarily interested in simulating the growing season ozone levels in Class I areas, daily and seasonal cumulative ozone exposure, as characterized by the W126 index, were also evaluated. The daily ozone W126 performance was not as good as the hourly ozone performance; however, the seasonal ozone W126 scaled up from daily values was within 17% of the observations at two typical Class I areas of the SAMI region. The overall ozone performance of the model was deemed acceptable for the purposes of SAMI's assessment. PMID:16111143

  13. [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

  14. Acid-base chemical reaction model for nucleation rates in the polluted atmospheric boundary layer.

    PubMed

    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

    2012-11-13

    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

  15. Acid-base chemical reaction model for nucleation rates in the polluted atmospheric boundary layer.

    PubMed

    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

    2012-11-13

    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.

  16. Acid-base chemical reaction model for nucleation rates in the polluted atmospheric boundary layer

    NASA Astrophysics Data System (ADS)

    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.

    2013-05-01

    Measurements of aerosol number distributions down to one molecule have provided information that we've used to develop a new approach for modeling atmospheric nucleation rates. Measurements were carried out with the Cluster Chemical Ionization Mass Spectrometer (Cluster CIMS), the scanning mobility spectrometer using a diethylene glycol condensation particle counter as detector (DEG SMPS), and an ambient pressure proton transfer mass spectrometer for ammonia and amines (AmPMS). The model explains nucleation as a result of cluster evolution due to a sequence of acid-base reactions. We conclude that the smallest stable cluster contains four sulfuric acid molecules. The model leads to a simple analytic expression for nucleation rates that is reasonably consistent (i.e., ± 10x) with atmospheric observations. The model predicts that nucleation rates are equal to a prefactor, P<1, times the sulfuric acid vapor collision rate, (i.e., J=Pṡ0.5ṡk11 *[H2SO4]2).

  17. Critical levels of atmospheric pollution: criteria and concepts for operational modelling of mercury in forest and lake ecosystems.

    PubMed

    Meili, Markus; Bishop, Kevin; Bringmark, Lage; Johansson, Kjell; Munthe, John; Sverdrup, Harald; de Vries, Wim

    2003-03-20

    Mercury (Hg) is regarded as a major environmental concern in many regions, traditionally because of high concentrations in freshwater fish, and now also because of potential toxic effects on soil microflora. The predominant source of Hg in most watersheds is atmospheric deposition, which has increased 2- to >20-fold over the past centuries. A promising approach for supporting current European efforts to limit transboundary air pollution is the development of emission-exposure-effect relationships, with the aim of determining the critical level of atmospheric pollution (CLAP, cf. critical load) causing harm or concern in sensitive elements of the environment. This requires a quantification of slow ecosystem dynamics from short-term collections of data. Aiming at an operational tool for assessing the past and future metal contamination of terrestrial and aquatic ecosystems, we present a simple and flexible modelling concept, including ways of minimizing requirements for computation and data collection, focusing on the exposure of biota in forest soils and lakes to Hg. Issues related to the complexity of Hg biogeochemistry are addressed by (1) a model design that allows independent validation of each model unit with readily available data, (2) a process- and scale-independent model formulation based on concentration ratios and transfer factors without requiring loads and mass balance, and (3) an equilibration concept that accounts for relevant dynamics in ecosystems without long-term data collection or advanced calculations. Based on data accumulated in Sweden over the past decades, we present a model to determine the CLAP-Hg from standardized values of region- or site-specific synoptic concentrations in four key matrices of boreal watersheds: precipitation (atmospheric source), large lacustrine fish (aquatic receptor and vector), organic soil layers (terrestrial receptor proxy and temporary reservoir), as well as new and old lake sediments (archives of response

  18. Atmospheric pollution in Lisbon urban atmosphere

    NASA Astrophysics Data System (ADS)

    Oliveira, C.

    2009-04-01

    Lisbon is the capital city of Portugal with about 565,000 residents in 2008 and a population density of 6,600 inhabitants per square kilometre. Like several other major metropolis, the town is surrounded by satellite cities, forming together a region known as "Lisbon Metropolitan Area" with about 3 million inhabitants, a quarter of the overall Portuguese population. Besides their local residents, it is estimated that more than one million citizens come into the Lisbon area every day from the outskirts, leading to elevated traffic densities and intense traffic jams, with important consequences on air pollution levels and obvious negative impacts on human health. Airborne particulate matter limit values are frequently exceeded, making urgent the existence of consistent programs to monitor and help taking measures to control them. Within the Portuguese project PAHLIS (Polycyclic Aromatic Hydrocarbons Contamination in Lisbon Urban Atmosphere) financed by the Portuguese Science Foundation ("Fundação para a Ciência e a Tecnologia"), an aerosol and vapour phase sampling program is being implemented in the city of Lisbon at two selected contrasting zones, namely a typically busy area with intense road traffic and frequent exceedences of the particulate matter standard for the maximum allowable concentration, and a residential quieter area, thus with a cleaner atmosphere characterised as an urban background site. An one month-long sampling campaign was performed during the summer of 2008, where particulate matter was collected in two fractions (coarse 2.5µm

  19. PLATIN (plant-atmosphere interaction) I: A model of plant-atmosphere interaction for estimating absorbed doses of gaseous air pollutants.

    PubMed

    Grünhage, L; Haenel, H D

    1997-01-01

    A PLant-ATmosphere INteraction model (PLATIN) was developed for estimating air pollutant absorbed doses under ambient conditions. PLATIN is based on the canopy energy balance combined with a gas transport submodel. The model has three major resistance components: (1) a turbulent atmospheric resistance Rah(zm) that describes the atmospheric transport properties between a measurement height above the canopy and the conceptual height z=d+z0m which represents the sink for momentum according to the big-leaf concept; (2) a quasilaminar layer resistance R(b,A) that quantifies the way in which the transfer of sensible heat and matter (e.g. latent heat, ozone) differs from momentum transfer; (3) a canopy or surface resistance R(c,A) that describes the influences of the plant/soil system on the exchange processes. Soil water content is simulated by a Force-Restore model. By a simple interception submodel precipitation and dew are partitioned into intercepted water and water reaching the soil surface. PLATIN can be run in a prognostic or a diagnostic mode. It is also intended for on-line use in air quality monitoring networks.

  20. 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...

  1. 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...

  2. 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

  3. 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.

  4. 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.

  5. 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

  6. 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

  7. 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

  8. 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.

  9. 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.

  10. Influence of synoptic and local atmospheric patterns on PM10 air pollution levels: a model application to Naples (Italy)

    NASA Astrophysics Data System (ADS)

    Fortelli, Alberto; Scafetta, Nicola; Mazzarella, Adriano

    2016-10-01

    We investigate the relationship between synoptic/local meteorological patterns and PM10 air pollution levels in the metropolitan area of Naples, Italy. We found that severe air pollution crises occurred when the 850 and 500 hpa geopotential heights and their relative temperatures present maximum values above the city. The most relevant synoptic parameter was the 850 hPa geopotential height, which is located about 1500 m of altitude. We compared local meteorological conditions (specifically wind stress, rain amount and thermal inversion) against the urban air pollution levels from 2009 to 2013. We found several empirical criteria for forecasting high daily PM10 air pollution levels in Naples. Pollution crises occurred when (a) the wind stress was between 1 and 2 m/s, (b) the thermal inversion between two strategic locations was at least 3°C/200 m and (c) it did not significantly rain for at least 7 days. Beside these meteorological conditions, severe pollution crises occurred also during festivals when fireworks and bonfires are lighted, and during anomalous breeze conditions and severe fire accidents. Finally, we propose a basic model to predict PM10 concentration levels from local meteorological conditions that can be easily forecast a few days in advance. The synthetic PM10 record predicted by the model was found to correlate with the PM10 observations with a correlation coefficient close to 0.80 with a confidence level greater than 99%. The proposed model is expected to provide reliable information to city officials to carry out practical strategies to mitigate air pollution effects. Although the proposed model equation is calibrated on the topographical and meteorological conditions of Naples, it should be easily adaptable to alternative locations.

  11. 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.

  12. 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

  13. 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…

  14. 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.

  15. 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.

  16. 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

  17. Some observational and modeling studies of the atmospheric boundary layer at Mississippi gulf coast for air pollution dispersion assessment.

    PubMed

    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

    2008-12-01

    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.

  18. Filtering effect of wind flow turbulence on atmospheric pollutant dispersion.

    PubMed

    Yassin, Mohamed F

    2012-06-01

    This paper presents a model for coupling the statistics of wind velocity distribution and atmospheric pollutant dispersion. The effect of wind velocity distribution is modeled as a three-dimensional finite-impulse response (3D-FIR) filter. A phase space representation of the 3D-FIR filter window is discussed. The resulting pollutant dispersion is the multiplication in the phase space of the 3-D Fourier transform of the pollutant concentration and the volume described by the filter window coefficients. The shape of the filter window in the phase space enables representing such effects as vortex shedding thermal currents, etc. The impact of spatial distribution of the sensors on the resulting pollutant spatial distribution and the 3-D FIR filter model employed also discuss. The case of a neutrally buoyant plume emitted from an elevated point source in a turbulent boundary layer considers. The results show that wind turbulence is an important factor in the pollutant dispersion and introduces expected random fluctuations in pollutant distribution and leads to spreading the distribution due to wind mixing.

  19. 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.

  20. Chemical Processing in a Polluted Forest Canopy: a Model Comparison of the Regional Atmospheric Chemistry Mechanism, Version 2 and SAPRC07

    NASA Astrophysics Data System (ADS)

    Goliff, W.; Stockwell, W. R.; Fuentes, J. D.

    2007-12-01

    In this study, we present a comparison of modeled chemical processing in polluted forest canopies using the Regional Atmospheric Chemistry Mechanism, Version 2 and SAPRC07. The comparison involves a number of field studies, one, for example, was conducted at a forested site near Oak Ridge, TN during the summer of 1999. The sites were under the influence of nitrogen oxide and hydrocarbon emissions from suburban automobile traffic. Air chemistry measurements (e.g., ozone, NOx and VOC) and meteorological measurements were collected within and above the forest canopies. A comparison of the degree of chemical processing by HO and NO3 radicals and O3 for biogenic compounds, and the amount of HOx formation between the two mechanisms is presented.

  1. 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.

  2. 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

  3. 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...

  4. Identifing Atmospheric Pollutant Sources Using Artificial Neural Networks

    NASA Astrophysics Data System (ADS)

    Paes, F. F.; Campos, H. F.; Luz, E. P.; Carvalho, A. R.

    2008-05-01

    The estimation of the area source pollutant strength is a relevant issue for atmospheric environment. This characterizes an inverse problem in the atmospheric pollution dispersion. In the inverse analysis, an area source domain is considered, where the strength of such area source term is assumed unknown. The inverse problem is solved by using a supervised artificial neural network: multi-layer perceptron. The conection weights of the neural network are computed from delta rule - learning process. The neural network inversion is compared with results from standard inverse analysis (regularized inverse solution). In the regularization method, the inverse problem is formulated as a non-linear optimization approach, whose the objective function is given by the square difference between the measured pollutant concentration and the mathematical models, associated with a regularization operator. In our numerical experiments, the forward problem is addressed by a source-receptor scheme, where a regressive Lagrangian model is applied to compute the transition matrix. The second order maximum entropy regularization is used, and the regularization parameter is calculated by the L-curve technique. The objective function is minimized employing a deterministic scheme (a quasi-Newton algorithm) [1] and a stochastic technique (PSO: particle swarm optimization) [2]. The inverse problem methodology is tested with synthetic observational data, from six measurement points in the physical domain. The best inverse solutions were obtained with neural networks. References: [1] D. R. Roberti, D. Anfossi, H. F. Campos Velho, G. A. Degrazia (2005): Estimating Emission Rate and Pollutant Source Location, Ciencia e Natura, p. 131-134. [2] E.F.P. da Luz, H.F. de Campos Velho, J.C. Becceneri, D.R. Roberti (2007): Estimating Atmospheric Area Source Strength Through Particle Swarm Optimization. Inverse Problems, Desing and Optimization Symposium IPDO-2007, April 16-18, Miami (FL), USA, vol 1, p

  5. Urban air pollution and atmospheric diffusion research in China

    NASA Astrophysics Data System (ADS)

    Ning, Datong; Whitney, Joseph B.; Yap, David

    1987-11-01

    Air pollution has become a serious problem in China as a result of that country's efforts in the last 30 years to become a great industrial power. The burning of coal, which currently provides over 70% of all China's energy needs, is a major source of air pollution. Because Chinese coal is high in sulfur and ash content and because most combustion devices in China have low efficiencies, SO2 and particulate emissions are a serious problem and are comparable to or exceed those found in many countries that are much more industrialized. Although most coal is burned in North China, acid precipitation is most severe in South China because of the lack of buffering loess dust found in the former region. The Chinese government has already taken major steps to mitigate air pollution, such as relocating polluting industries, supplying coal with lower sulfur content, using gas instead of coal for residential heating, and levying fines on industries that exceed pollution standards. Atmospheric environmental impact assessment (AEIA) is also required for all major new projects. This article describes three types of mathematical diffusion models and field and wind-tunnel experiments that are used in such assessments. The Chinese authorities believe that a range of technological, managerial, locational, and behavioral changes must be effected before the air of Chinese cities can be significantly improved.

  6. 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.

  7. 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

  8. 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

  9. 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.

  10. 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

  11. Community Atmosphere Model

    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

  12. Ensemble Atmospheric Dispersion Modeling

    SciTech Connect

    Addis, R.P.

    2002-06-24

    Prognostic atmospheric dispersion models are used to generate consequence assessments, which assist decision-makers in the event of a release from a nuclear facility. Differences in the forecast wind fields generated by various meteorological agencies, differences in the transport and diffusion models, as well as differences in the way these models treat the release source term, result in differences in the resulting plumes. Even dispersion models using the same wind fields may produce substantially different plumes. This talk will address how ensemble techniques may be used to enable atmospheric modelers to provide decision-makers with a more realistic understanding of how both the atmosphere and the models behave.

  13. 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.

  14. 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.

  15. 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)

  16. A GRAPHICAL DIAGNOSTIC METHOD FOR ASSESSING THE ROTATION IN FACTOR ANALYTICAL MODELS OF ATMOSPHERIC POLLUTION. (R831078)

    EPA Science Inventory

    Factor analytic tools such as principal component analysis (PCA) and positive matrix factorization (PMF), suffer from rotational ambiguity in the results: different solutions (factors) provide equally good fits to the measured data. The PMF model imposes non-negativity of both...

  17. Adaptation of plants to atmospheric pollutants.

    PubMed

    Hutchinson, T C

    1984-01-01

    Man-made air pollutants are a recent phenomenon in the evolutionary experience of plants and animals although natural air pollutants from volcanic eruptions, forest fires and dust storms have accompanied evolution for geological eras. Plants have responded to increasing concentrations of such pollutants as sulphur dioxide, fluorides, photochemical oxidants and acid rain at the community, species, population and individual levels. The lichens and bryophytes have shown particularly dramatic changes in urban and industrial areas. Many species have had their distribution severely limited. Tolerances to sulphur dioxide have evolved in populations of a number of grasses and herbs, and some sulphur dioxide-tolerant lichens have invaded inner city areas. Sensitivity to pollutants is partly a function of substrate chemistry. Synergistic interactions occur between various pollutants and also between pollutants and pathogens. A good deal of genetic variation occurs within crops, and this allows for selection of pollution-tolerant varieties. The nature of specific adaptations is not generally well known although, for sulphur dioxide, recent studies in poplar and spinach strongly suggest that increased production of the enzyme superoxide dismutase may be a key factor. In other adaptations, morphological and anatomical features play a part.

  18. Atmospheric Models for Aerocapture

    NASA Technical Reports Server (NTRS)

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

    2004-01-01

    There are eight destinations in the solar System with sufficient atmosphere for aerocapture to be a viable aeroassist option - Venus, Earth, Mars, Jupiter, Saturn and its moon Titan, Uranus, and Neptune. Engineering-level atmospheric models for four of these targets (Earth, Mars, Titan, and Neptune) have been developed for NASA to support systems analysis studies of potential future aerocapture missions. Development of a similar atmospheric model for Venus has recently commenced. An important capability of all of these models is their ability to simulate quasi-random density perturbations for Monte Carlo analyses in developing guidance, navigation and control algorithm, and for thermal systems design. Similarities and differences among these atmospheric models are presented, with emphasis on the recently developed Neptune model and on planned characteristics of the Venus model. Example applications for aerocapture are also presented and illustrated. Recent updates to the Titan atmospheric model are discussed, in anticipation of applications for trajectory and atmospheric reconstruct of Huygens Probe entry at Titan.

  19. Plants as bioassay systems for monitoring atmospheric pollutants

    PubMed Central

    Feder, William A.

    1978-01-01

    Plant species act as natural bioindicators of atmospheric pollutants. Plants can be used as bioassay systems for monitoring atmospheric pollutants. Plant injury symptoms, altered growth and reproductive pattern, changes in yield and/or productivity, and changes in species distribution can be used singly or in combination as monitoring devices. The results must be accepted as semiquantitative, but within that constraint, air quality can be sufficiently well defined to enable the setting of air quality standards. Genetic variability of higher plant species has yielded cultivars which display a range of tolerance to gaseous and particulate atmospheric pollutants. Asexual propagation of these cultivars provides pollutant-sensitive and pollutant-tolerant plant material which can be grown on selected sites for observation. Gymnosperm and Angiosperm species as well as species of lichens and mosses have been used to establish field monitoring networks in Europe, Canada, and the United States. White pine, shade tobacco, mosses, and lichens have proven particularly useful as bioassay tools. Pollen from pollutant-sensitive and pollutant-tolerant plant cultivars has also been used as a sensitive laboratory bioassay tool for studying air quality. Epiphytic mosses are particularly efficient as monitors of particulate pollutants, especially heavy metals, some of which may act as chemical mutagens. The cost, complexity, and lack of reliability of instrumented systems for air quality monitoring make imperative the need to develop successful plant bioassay systems for monitoring air quality. PMID:738233

  20. 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.

  1. 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.

  2. 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

  3. 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.

  4. Effects of pollutant atmospheres on surface receptors of pulmonary macrophages

    SciTech Connect

    Prasad, S.B.; Rao, V.S.; Mannix, R.C.; Phalen, R.F.

    1988-01-01

    The effects of two multicomponent pollutant atmospheres on the surface receptors (FcR) and phagocytic activity of rat pulmonary alveolar macrophages have been studied. FcR are crucial for the macrophages to become cytotoxic against target cells. The atmospheres were composed of pollutants that are prevalent in the South Coast Air Basin of southern California. Rats were exposed nose-only to a 7-component oxidant-and sulfate-containing atmosphere for 4 h/d for either 7 or 21 consecutive days. In another experiment rats were exposed 5 h/d for 5 consecutive days to another pollutant combination--acid droplets plus carbon-containing dilute diesel engine exhaust. In both experiments matched rats were exposed nose-only to purified air to be used as controls. Each of the atmospheres studied significantly reduced FcR activity for at least 3 d following the exposure, with the group of rats exposed to the 7-component atmosphere for 21 d exhibiting the most pronounced effect. Macrophages from rats exposed to the diesel exhaust plus acid atmosphere and the 7-component atmosphere for 7 d had significantly reduced phagocytic activity for at least 3 d postexposure, while the macrophages from rats exposed to the latter atmosphere for 21 d had phagocytic activity near control values. The decrease in phagocytosis and inhibition of FcR of macrophages suggests an impairment of macrophage function that probably renders the host vulnerable to bacterial and/or viral infections.

  5. Atmospheric ozone and man-made pollution.

    PubMed

    Fabian, P

    1976-06-01

    Atmospheric photochemistry and transport processes, related to the ozone layer, are discussed. Natural or man-made changes of the biosphere, variations of radiation, or general circulation as well as anthropogenic release of ozone-destroying catalysts are likely to alter the earth's ozone shield. The possible effects of ozone depletion caused by supersonic aircraft, nuclear weapons, nitrogen fertilizers, and chlorofluoromethanes are discussed.

  6. 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

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. Global Monitoring of Atmospheric Pollutants from the Aura Satellite

    NASA Astrophysics Data System (ADS)

    Ahmad, S.; Leptoukh, G.; Johnson, J.; Farley, J.; Kempler, S.

    2007-12-01

    Atmospheric measurements of O3, CO, NO2, SO2, HCHO, Aerosol and other pollutants are routinely made by the OMI, MLS, HIRDLS and TES instruments flown on the EOS Aura satellite since its launch in July 2004. These measurements provide information on the vertical and horizontal distribution of atmospheric pollutants. High concentrations of these pollutants come principally from motor vehicle exhaust, coal and oil combustion, refineries, and biomass burning. These gases play a major role in the formation of unhealthy ground level ozone (or smog) and can trigger serious respiratory problems. The convective transport of these gases, smoke and dust also pollute the upper troposphere and lower stratosphere where the residence time of these pollutants is relatively long and atmospheric winds transport these pollutants to far distances across the oceans and continents. This presentation provides some examples of how Aura data can be used in monitoring air quality by identifying sources of air pollution and understanding the distribution of these pollutants as they get transported extensive distances from their source. In this study we have also used the Aerosol Index data from TOMS, CO data from MOPITT and AIRS, Aerosol data from MODIS, Aerosol layer height information from CALIPSO, and wind information from the NCEP/NCAR reanalysis. This study uses the web based data exploration and analysis tool Giovanni developed at the NASA Goddard Earth Sciences Data Services and Information Center (GES DSIC). Giovanni provides easy access to satellite data, eliminating the need to download large data sets and thus saving the user time. Giovanni capabilities include on- line animations of 2D maps, time-series plots (including statistics), several combinations of 2D cross-section maps (latitude/longitude/height/time), scatter plots, correlation maps, and collocated subsets of the data along CALIPSO tracks.

  12. 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 -…

  13. Nonlinear dynamics of the atmospheric pollutants in Mexico City

    NASA Astrophysics Data System (ADS)

    Muñoz-Diosdado, Alejandro; Barrera-Ferrer, Amilcar; Angulo-Brown, Fernando

    2014-05-01

    The atmospheric pollution in the Metropolitan Zone of Mexico City (MZMC) is a serious problem with social, economical and political consequences, in virtue that it is the region which concentrates both the greatest country population and a great part of commercial and industrial activities. According to the World Health Organization, maximum permissible concentrations of atmospheric pollutants are exceeded frequently. In the MZMC, the environmental monitoring has been limited to criteria pollutants, named in this way due to when their levels are measured in the atmosphere, they indicate in a precise way the air quality. The Automatic Atmospheric Monitoring Network monitors and registers the values of pollutants concentration in air in the MZMC. Actually, it is integrated by approximately 35 automatic-equipped remote stations, which report an every-hour register. Local and global invariant quantities have been widely used to describe the fractal properties of diverse time series. In the study of certain time series, many times it is assumed that they are monofractal, which means that they can be described only with one fractal dimension. But this hypothesis is unrealistic because a lot of time series are heterogeneous and non stationary, so their scaling properties are not the same throughout time and therefore they may require more fractal dimensions for their description. Complexity of the atmospheric pollutants dynamics suggests us to analyze its time series of hourly concentration registers with the multifractal formalism. So, in this work, air concentration time series of MZMC criteria pollutants were studied with the proposed method. The chosen pollutants to perform this analysis are ozone, sulfur dioxide, carbon monoxide, nitrogen dioxide and PM10 (particles less than 10 micrometers). We found that pollutants air concentration time series are multifractal. When we calculate the degree of multifractality for each time series we know that while more

  14. Terrestrial mosses as biomonitors of atmospheric POPs pollution: a review.

    PubMed

    Harmens, H; Foan, L; Simon, V; Mills, G

    2013-02-01

    Worldwide there is concern about the continuing release of persistent organic pollutants (POPs) into the environment. In this study we review the application of mosses as biomonitors of atmospheric deposition of POPs. Examples in the literature show that mosses are suitable organisms to monitor spatial patterns and temporal trends of atmospheric concentrations or deposition of POPs. These examples include polycyclic aromatic hydrocarbons (PAHs), polychlorobiphenyls (PCBs), dioxins and furans (PCDD/Fs), and polybrominated diphenyl ethers (PBDEs). The majority of studies report on PAHs concentrations in mosses and relative few studies have been conducted on other POPs. So far, many studies have focused on spatial patterns around pollution sources or the concentration in mosses in remote areas such as the polar regions, as an indication of long-range transport of POPs. Very few studies have determined temporal trends or have directly related the concentrations in mosses with measured atmospheric concentrations and/or deposition fluxes.

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

    PubMed

    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

  16. 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

  17. 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.

  18. [Influence of atmospheric transport on air pollutant levels at a mountain background site of East China].

    PubMed

    Su, Bin-Bin; Xu, Ju-Yang; Zhang, Ruo-Yu; Ji, Xian-Xin

    2014-08-01

    Transport characteristics of air pollutants transported to the background atmosphere of East China were investigated using HYSPLIT (Hybrid Single Particle Lagrangian Integrated Trajectory) 4.8 model driven by NCEP reanalysis data during June 2011 to May 2012. Based on the air pollutants monitoring data collected at the National atmospheric background monitoring station (Wuyishan station) in Fujian Province, characteristics of different clustered air masses as well as the origins of highly polluted air masses were further examined. The results showed that 65% of all the trajectories, in which air masses mainly passed over highly polluted area of East China, Jiangxi province and upper air in desert areas of Northwest China, carried polluted air to the station, while the rest of trajectories (35%) with air masses originated from ocean could effectively remove air pollutants at the Wuyishan station. However, the impact on the air pollutants for each air mass group varied with seasons. Elevated SO2 concentrations observed at the background station were mainly influenced by coal burning activities in Northern China during heating season. The high CO concentrations were likely associated with the pollutants emission in the process of coal production and consumption in Anhui province. The elevated NO(x), O3, PM10 and PM2.5 concentrations were mostly impacted by East China with high levels of air pollutants.

  19. 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.

  20. Atmospheric pollution originating from the interaction of different gaseous effluents.

    PubMed

    Bartùli, C; Botrè, C; Botrè, F; Pecci, G

    1997-01-01

    During the last few years, several episodes of atmospheric pollution have been reported in a limited area near Guidonia, Rome. The area contains a disposal plant, Inviolata, for the collection of municipal solid waste (MSW) and a famous thermal water resort, the Acque Albule spring, which is a source of water rich in H2S. We conducted a multiparametric study in the areas surrounding the solid waste disposal plant and the Acque Albule spring. The concentration of main gaseous effluent was continuously monitored over a period of 4 months and the data relating to the meteorologic conditions in the area during the last few decades were examined. Our results suggest that most of the atmospheric pollution is due to the interaction of different gaseous effluents. Specifically, the presence of relatively high levels of hydrogen sulfide in the atmosphere, constantly released in large amounts by the Acque Albule springs, and of biogases (mainly hydrocarbons) from the organic matter present in the solid waste continuously unloaded and stored at the disposal plant, lead to mixing and photochemical interactions between these chemical compounds, which in turn are responsible for most of the polluting effects. Such interactions are promoted by the strong solar irradiation in the area that is enhanced by the peculiar local meteorological features that do not allow the pollutants to disperse.

  1. Trans boundary transport of pollutants by atmospheric mineral dust.

    PubMed

    Erel, Yigal; Dayan, Uri; Rabi, Reut; Rudich, Yinon; Stein, Mordechai

    2006-05-01

    The transport of anthropogenic pollution by desert dust in the Eastern Mediterranean region was studied by analyzing major and trace element composition, organic species, and Pb isotope ratios in suspended dust samples collected in Jerusalem, Israel. Dust storms in this region are associated with four distinct synoptic conditions (Red Sea Trough (RS), Eastern High (EH), Sharav Cyclone (SC), and Cold Depression (Cyprus low, CD)) that carry dust mostly from North African (SC, CD, EH) and Arabian and Syrian (RS, EH) deserts. Substantial contamination of dust particles by Pb, Cu, Zn, and Ni is observed, while other elements (Na, Ca, Mg, Mn, Sr, Rb, REE, U, and Th) display natural concentrations. Sequential extraction of the abovementioned elements from the dust samples shows that the carbonate and sorbed fractions contain most of the pollution, yet the Al-silicate fraction is also contaminated, implying that soils and sediments in the source terrains of the dust are already polluted. We identified the pollutant sources by using Pb isotopes. It appears that before the beginning of the dust storm, the pollutants in the collected samples are dominated by local sources but with the arrival of dust from North Africa, the proportion of foreign pollutants increases. Organic pollutants exhibit behavior similar and complementary to that of the inorganic tracers, attesting to the importance of anthropogenic-pollutant addition en route of the dust from its remote sources. Pollution of suspended dust is observed under all synoptic conditions, yet it appears that easterly winds carry higher proportions of local pollution and westerly winds carry pollution emitted in the Cairo basin. Therefore, pollution transport by mineral dust should be accounted for in environmental models and in assessing the health-related effects of mineral dust.

  2. 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.

  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. 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.

  5. Prediction of asthma exacerbations among children through integrating air pollution, upper atmosphere, and school health surveillances.

    PubMed

    Jayawardene, Wasantha Parakrama; Youssefagha, Ahmed Hassan; Lohrmann, David Kurt; El Afandi, Gamal Salah

    2013-01-01

    Climatic factors and air pollution are important in predicting asthma exacerbations among children. This study was designed to determine if a relationship exists between asthma exacerbations among elementary school children and the combined effect of daily upper atmosphere observations (temperature, relative humidity, dew point, and mixing ratio) and daily air pollution (particulate matter, sulfur dioxide, nitrogen dioxide, carbon monoxide, and ozone) and, if so, to predict asthma exacerbations among children using a mathematical model. Using an ecological study design, school health records of 168,825 students in elementary schools enrolled in "Health eTools for Schools" within 49 Pennsylvania counties were analyzed. Data representing asthma exacerbations were originally recorded by school nurses as the type of treatment given to a student during a clinic visit on a particular day. Daily upper atmosphere measurements from ground level to the 850-mb pressure level and air pollution measurements were obtained. A generalized estimating equation model was used to predict the occurrence of >48 asthma exacerbations, the daily mean for 2008-2010. The greatest occurrence of asthma among school children was in the fall, followed by summer, spring, and winter. Upper atmosphere temperature, dew point, mixing ratio, and six air pollutants as well as their interactions predicted the probability of asthma exacerbations occurring among children. Monitoring of upper atmosphere observation data and air pollutants over time can be a reliable means for predicting increases of asthma exacerbations among elementary school children. Such predictions could help parents and school officials implement effective precautionary measures.

  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.

  7. 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.

  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. 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.

  10. 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.

  11. MARCS model atmospheres

    NASA Astrophysics Data System (ADS)

    Plez, B.

    2008-12-01

    In this review presented at the Symposium A Stellar Journey in Uppsala, June 2008, I give an account of the historical development of the MARCS code, and its premises from the first version published in 1975 to the 2008 grid. The primary driver for the development team who constantly strive to include the best possible physical data, is the science that can be done with the models. A few preliminary comparisons of M star model spectra to spectrophotometric observations are presented. Particular results related to opacity effects are discussed. The size of errors in spectral energy distribution (SED) and model thermal stratification is estimated for different densities of wavelength sampling. The number of points used in the MARCS 2008 grid (108 000) is large enough to ensure errors of only a few K in all models of the grid, except the optically very thin layers of metal-poor stars. Errors in SEDs may reach about 10% locally in the UV. The published sampled SEDs are thus adequate to compute synthetic broadband photometry, but higher resolution spectra will be computed in the near future and published as well on the MARCS site (marcs.astro.uu.se). Test model calculations with TiO line opacity accounted for in scattering show significant cooling of the upper atmospheric layers of red giants. Rough estimates of radiative and collisional time scales for electronic transitions of TiO indicate that scattering may well be the dominant mechanism in these lines. However, models constructed with this hypothesis are incompatible with optical observations of TiO (Arcturus) or IR observations of OH (Betelgeuse), although they may succeed in explaining H2O line observations. More work is needed in that direction.

  12. [Observation on atmospheric pollution in Xianghe during Beijing 2008 Olympic Games].

    PubMed

    Pan, Yue-Peng; Wang, Yue-Si; Hu, Bo; Liu, Quan; Wang, Ying-Hong; Nan, Wei-Dong

    2010-01-01

    There is a concern that much of the atmospheric pollution experienced in Beijing is regional in nature and not attributable to local sources. The objective of this study is to examine the contribution of sources outside Beijing to atmospheric pollution levels during Beijing 2008 Olympic Games. The observations of SO2, NO(x), O3, PM2.5 and PM10 were conducted from June 1 to September 30, 2008 in Xianghe, a rural site about 70 km southeast of Beijing. Sources and transportation of atmospheric pollution during the experiment were discussed with surface meteorology data and backward trajectories calculated using HYSPLIT model. The results showed that the daily average maximum (mean +/- standard deviation) concentrations of SO2, NO(x), O3, PM2.5, and PM10 during observation reached 84.4(13.4 +/- 15.2), 43.3 (15.9 +/- 9.1), 230 (82 +/- 38), 184 (76 +/- 42) and 248 (113 +/- 52) microg x m(-3), respectively. In particular, during the pollution episodes from July 20 to August 12, the hourly average concentration of O3 exceeded the National Ambient Air Quality Standard II for 46 h (9%), and the daily average concentration of PM10 exceeded the Standard for 11 d (46%); PM2.5 exceeded the US EPA Standard for 18 d (75%). The daily average concentrations of SO2, NO(x), O3, PM2.5 and PM10 decreased from 27.7, 18.6, 96, 90, 127 microg x m(-3) in June-July to 5.8, 13.2, 80, 60, 106 microg x m(-3) during Olympic Games (August-September), respectively. The typical diurnal variations of NO(x), PM2.5 and PM10 were similar, peaking at 07:00 and 20:00, while the maximum of O3 occurred between 14:00 to 16:00 local time. The findings also suggested that the atmospheric pollution in Xianghe is related to local emission, regional transport as well as the meteorological conditions. Northerly wind and precipitation are favorable for diffusion and wet deposition of pollutants, while sustained south flows make the atmospheric pollution more serious. The lead-lag correlation analysis during the

  13. 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.

  14. Advanced Atmospheric Modeling for Emergency Response.

    NASA Astrophysics Data System (ADS)

    Fast, Jerome D.; O'Steen, B. Lance; Addis, Robert P.

    1995-03-01

    Atmospheric transport and diffusion models are an important part of emergency response systems for industrial facilities that have the potential to release significant quantities of toxic or radioactive material into the atmosphere. An advanced atmospheric transport and diffusion modeling system for emergency response and environmental applications, based upon a three-dimensional mesoscale model, has been developed for the U.S. Department of Energy's Savannah River Site so that complex, time-dependent flow fields not explicitly measured can be routinely simulated. To overcome some of the current computational demands of mesoscale models, two operational procedures for the advanced atmospheric transport and diffusion modeling system are described including 1) a semiprognostic calculation to produce high-resolution wind fields for local pollutant transport in the vicinity of the Savannah River Site and 2) a fully prognostic calculation to produce a regional wind field encompassing the southeastern United States for larger-scale pollutant problems. Local and regional observations and large-scale model output are used by the mesoscale model for the initial conditions, lateral boundary conditions, and four-dimensional data assimilation procedure. This paper describes the current status of the modeling system and presents two case studies demonstrating the capabilities of both modes of operation. While the results from the case studies shown in this paper are preliminary and certainly not definitive, they do suggest that the mesoscale model has the potential for improving the prognostic capabilities of atmospheric modeling for emergency response at the Savannah River Site. Long-term model evaluation will be required to determine under what conditions significant forecast errors exist.

  15. Microbial release of sulphur ions from atmospheric pollution deposits

    SciTech Connect

    Killhan, K.; Wainwright, M.

    1981-12-01

    The surfaces of leaves of Acer pseudoplatanus growing in areas exposed to heavy atmospheric pollution are covered with atmospheric pollution deposits (APD). Using scanning electron microscopy, micro-organisms were seen to be growing in intimate association with these deposits. The deposits contained sufficient carbon and nitrogen to support growth of the fungus Fusarium solani in culture and in autoclaved and non-sterilized soils; and sufficient reduced sulphur for the in vitro growth of Thiobacillus thioparus. When T. thioparus and F. solani were grown in medium supplemented with APD as sole carbon and nitrogen sources, increases in the concentrations of soluble S/sub 2/O/sup 2 -//sub 3/; S/sub 4/O/sup 2 -//sub 6/ and SO/sup 2 -//sub 4/ resulted. Similar increases also occurred when APD was added to complete fungal growth medium. Increases in LiCl/sub 2/-extractable sulphur-ions also occurred in fresh soil amended with APD, and in autoclaved soils containing APD, and inoculated with spores of F. solani. Arylsulphatase activity increased in fresh soils and in soils autoclaved and inoculated with F. solani when APD was added; suggesting sulphur mineralization, as well as sulphur oxidation, in the release of sulphur ions from APD. We concluded that APD can support microbial growth in vitro and in soils when provided as sole carbon and sulphur source; and that micro-organisms can release sulphur ions from this complex substrate. Microbial release of sulphur ions from APD can account in part for the increased concentrations of sulphur ions in heavy atmospheric-polluted soils.

  16. Microbial release of sulphur ions from atmospheric pollution deposits

    SciTech Connect

    Killham, K.; Wainwright, M.

    1981-12-01

    The surface of leaves of Acer pseudoplatanus growing in areas exposed to heavy atmospheric pollution are covered with atmospheric pollution deposits (APD). Using scanning electric microscopy, micro-organisms were seen to be growing in intimate association with these deposits. The deposits contained sufficient carbon and nitrogen to support growth of the fungus Fusarium solani in culture and in autoclaved and non-sterilized soils; and sufficient reduced sulphur for in vitro growth of Thiobacillus thioparus. When T. thioparus and F. solani were grown in medium supplemented with APD as sole carbon and nitrogen sources, increases in the concentrations of soluble S/sub 2/O/sub 3//sup 2/ btw/sup -/ and; S/sub 4/O/sub 6//sup 2 -/ and SO/sub 4//sup 2 -/ resulted. Similar increases also occurred when APD was added to complete fungal growth medium. Increases in LiCl/sub 2/-extractable sulphur-ions also occurred is fresh soil amended with APD, and in autoclaved soils containing APD, and inoculated with spores of F. solani. Arylsulphatase activity increased in fresh soils and in soils autoclaved and inoculated with F. solani when APD was added; suggesting sulphur mineralization, as well as sulphur oxidation, in the release of sulphur ions from APD. We conclude that APD can support microbial growth in vitro and in soils when provided as sole carbon and sulphur source; and that micro-organisms can release sulphur ions from this complex substrate. Microbial release of sulphur ions from APD can account in part for the increased concentrations of sulphur ions in heavy atmospheric-polluted soils.

  17. Global Transport of Organic Pollutants: Ambient Concentrations in the Remote Marine Atmosphere

    NASA Astrophysics Data System (ADS)

    Atlas, E.; Giam, C. S.

    1981-01-01

    Concentrations of organic pollutants in the air and in precipitation have been measured at Enewetak Atoll in the North Pacific Ocean. These data from a site removed from industrial and human activity indicate the present concentrations of synthetic organic pollutants in the atmosphere and establish the long-range atmospheric transport of organic pollutants to remote marine areas. Hexachlorobenzene and hexachlorocyclohexane isomers are present in the remote marine atmosphere. Polychlorobiphenyls, total DDT, dieldrin, chlordane, and two phthalate ester plasticizers were also found in the samples. The concentrations of pollutants in the atmosphere remote from continental sources are good measures of the minimum concentrations of air pollutants on Earth.

  18. 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.

  19. The effect of atmospheric pollution on building materials

    NASA Astrophysics Data System (ADS)

    Grossi, C. M.; Brimblecombe, P.

    2002-11-01

    This chapter surveys main effects of atmospheric pollution on building materials. It summarises these effects on stone, bricks, mortar, concrete, glass, metals (iron, zinc, copper, bronze, aluminium, lead and silver), polymers, paints and timber. Special attention is paid to stone because of its extensive use as building material in the cultural heritage. In general, main damaging agent is sulfur dioxide which leads to sulfation of many materials, particularly carbonate-bearing stones. However, the decline of sulfur dioxide in cities means that the recognition of the prime role of this pollutant presents something of a dilemma. It is increasingly necessary to consider other substances that can contribute to material decay e.g. nitrogen oxides, chlorides and ozone, either acting as synergistic to the sulfation reaction or as main decay agents, such as the case of aluminium and polymers. Particulate matter often from diesel vehicles can also accelerate the oxidation of SO2 on the surface (traditionally sulfur dioxide with Fe-rich particles) and blacken the materials surface in the case of soot. These processes contribute to the formation of black-crusts when embedded in the gypsum layer resulting from the material sulfation, but again the rate in the modem atmosphere is a matter of much research.

  20. 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.

  1. [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.

  2. Monitoring atmospheric levels and deposition of dioxin-like pollutants in sub-alpine Northern Italy

    NASA Astrophysics Data System (ADS)

    Castro-Jiménez, J.; Eisenreich, S. J.; Mariani, G.; Skejo, H.; Umlauf, G.

    2012-09-01

    The objective of this work was to assess the atmospheric occurrence, seasonal variations and deposition of dioxin-like pollutants (17 PCDD/Fs + 12 DL-PCBs) in sub-alpine northern Italy. A total of 108 weekly integrated samples (aerosol + gas phases) were collected during a 1-year period (2005-2006) at the Ispra EMEP site (Northern Italy, 45°49'N, 8°38'E). Atmospheric loadings into Lake Maggiore were also estimated by implementing a deposition model. ∑2,3,7,8-PCDD/F atmospheric total concentrations were dominated by the aerosol-bound fraction which ranged from 50 to 3080 (1-215 WHO98 TEQ) fg m-3. In contrast DL-PCB levels were dominated by the gas phase concentrations and varied from 1800 to 14800 (1-5 WHO98 TEQ) fg m-3. The aerosol and gas phase concentrations of PCDD/Fs and DL-PCBs exhibited a similar seasonality (higher values in winter time for aerosol-bound contaminants and lower concentrations for gas phase contaminants) in spite of their different environmental sources and properties. Estimated total atmospheric (dry + wet) depositional fluxes of dioxin-like pollutants in sub-alpine northern Italy were ˜0.2-˜9.5 ng m-2 d-1, with wet deposition dominating. Total atmospheric inputs (2,3,7,8-PCDD/Fs + DL-PCBs) into Lake Maggiore ranged from 14 to 304 g y-1. Higher environmental concentrations of dioxin-like pollutants in sub-alpine northern Italy are expected in the cold season and in rainy days due to a combined effect of stagnant atmospheric conditions (low winds), household wood burning in the region and higher pollutant loads via rainfall in winter.

  3. 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.

  4. 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.

  5. 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

    2016-11-01

    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.

  6. 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

  7. Planetary atmosphere modeling and predictions

    NASA Technical Reports Server (NTRS)

    Berman, A. L.

    1977-01-01

    The capability to generate spacecraft frequency predictions which include the refractive bending effects induced during signal passage through a planetary atmosphere is a pivotal element of the DSN Radio Science System. This article describes the current implementation effort to develop planetary atmosphere modeling and prediction capability.

  8. 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.

  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. 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.

  11. Atmospheric transport of persistent organic pollutants to the Arctic, today and in a future climate

    NASA Astrophysics Data System (ADS)

    Octaviani, Mega; Stemmler, Irene; Lammel, Gerhard

    2013-04-01

    Persistent organic pollutants are of great concern because of their long residence time and long-range transport potential in the environment and because they are readily bioaccumulated along food chains and toxic for wildlife and humans. A multicompartment model is used to study global-scale and long term chemodynamics of anthropogenic organic substances in the Earth system. Model components are the atmosphere (ECHAM5) and ocean general circulation models (MPIOM), which include dynamic sub-models for atmospheric aerosols and the marine biogeochemistry, two-dimensional surface compartments (topsoil, vegetation surfaces, ice, and temporal snow cover) and intercompartmental mass exchange process parameterisations [1-3]. The transports into and out of the Arctic (66° N) are characterized for 1950-2000 under one realisation of present-day climate [4-5] and for 2001-2100 under one realisation of future climate (greenhouse gas emission scenario A1B of IPCC-AR4). Despite decaying primary emissions (since decades) polychlorinated biphenyls (PCB) and dichlorodimephenyltrichloromethane (DDT) are continuing to accumulate in the Arctic, which is fed by atmospheric transports. The main regions of import (and export) are identified and the vertical distribution and seasonalities are characterized. Changes by the end of the 21st century are discussed in the context of a major teleconnection, i.e. the Arctic Oscillation. References [1] Guglielmo F, Lammel G, Maier-Reimer E: Global environmental cycling of DDT and ?-HCH in the 1980s - a study using a coupled atmosphere and ocean general circulation model. Chemosphere 76 (2009) 1509-1517 [2] Stemmler I, Lammel G: Cycling of DDT in the global oceans 1950-2002: World ocean returns the pollutant. Geophys. Res. Lett. 36 (2009) L24602 [3] Hofmann L, Stemmler I, Lammel G: The impact of organochlorines cycling in the cryosphere on their global distributions and fate - 2. Land ice and temporary snow cover. Environ. Pollut. 162 (2012) 482

  12. Study of the Mechanism of Nucleation in the Polluted Atmospheric Boundary Layer

    NASA Astrophysics Data System (ADS)

    Chen, Modi

    Atmospheric aerosols can affect human health and earth's radiation balance. The formation of these aerosols has been shown to cast high uncertainty in current global climate modeling. Most observed nucleation events in the boundary layers are correlated with high sulfuric acid concentration. Nucleation rates are usually proportional to sulfuric acid concentration up to the third power. After atmospheric aerosol particles are formed, they often grow at a speed faster than can be explained by sulfuric acid condensation, suggesting that other chemical species also participate in this process. The detailed mechanisms of how these particles are formed and their subsequent growth are still unclear. This work is focused on furthering our understanding of atmospheric nucleation. My contribution is mainly on the following three topics: (1) characterizing condensation particle counters (CPCs) for accurate particle measurements down to 1 nm, the size close to the smallest stable sulfuric acid clusters; (2) developing a method of estimating time and size resolved particle growth rates and atmospheric nucleation rates based on data from both atmospheric and laboratory studies; (3) deriving of a simple semi-empirical acid-base reaction model for atmospheric nucleation in the polluted atmospheric boundary layer.

  13. 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 ...

  14. 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.

  15. Model simulations for Europa's atmosphere

    NASA Astrophysics Data System (ADS)

    Wong, M. C.; Carlson, R. W.; Johnson, R. E.

    2000-10-01

    Europa's tenuous atmosphere is thought to be produced from sputtering of surface species (predominantly H2O ice ) by heavy ions in the Jovian magnetosphere. Because of its low residence time at Europa's surface temperature, O2, a stable decomposition product of H2O, has been predicted to exist in a significant amount in Europa's atmosphere [Johnson et al. 1982, Eviatar et al. 1985, Johnson 1990]. Recent HST observations have confirmed that and suggested an O2 atmospheric column of 1015 cm-2 on Europa [Hall et al. 1995]. Recent theoretical studies applied to modeling of pure oxygen atmospheres on Europa [Ip et al. 1996, Saur et al. 1998, Shematovich and Johnson 2000] have produced results that are consistent with the above scenerio. In addition to water products, recent observations from Galileo NIMS instruments have suggested the existence of hydrated salt minerals and sulfuric acid on Europa's surface [McCord et al. 1999, Carlson et al. 1999]. Therefore, it is expected that decomposition of these materials by magnetospheric ions can produce volatile species such as H2S, SO2, CO2 and Na in Europa's atmosphere. In fact, Na has been identified in the extended atmosphere of Europa [Brown and Hill, 1996]. In this paper, we will use a kinetic model to study the fate and abundance of these volatile species in addition to simulating the formation of an oxygen atmosphere on Europa.

  16. Comparative influences of airborne pollutants and meteorological parameters on atmospheric visibility and turbidity

    NASA Astrophysics Data System (ADS)

    Wen, Chih-Chung; Yeh, Hui-Hsuan

    2010-06-01

    The purpose of this paper was to investigate how atmospheric air pollutants and meteorological conditions affect atmospheric visibility and turbidity. Meteorological parameter and anthropogenic air pollutant values were recorded during 2004 and 2005 at the Wuchi weather station and the Sha-lu environmental quality database station at the Taichung Harbor near the Taiwan Strait. Local weather conditions (temperature, relative humidity and solar radiation) and airborne pollutant (PM 10, SO 2, NO 2, CO and O 3) concentrations were used to analyze the relative effects of atmospheric air pollutants and meteorological conditions on atmospheric visibility and turbidity. Based on the analytic results, air pollutant concentrations significantly influence visibility and atmospheric turbidity. Wind speed is an important meteorological parameter that affects atmospheric turbidity parameters at the same atmospheric air pollutant concentrations throughout the periods of observation. At wind speeds of greater than 7 m/s, the turbidity factor β Vis is below 0.3 and visibility is greater than 6.5 km. Under very turbid conditions, β Vis > 0.4, the wind velocity is below 5 m/s, regardless of the atmospheric pollutant concentration. When visibility is ≥ 11 km, the PM 10 concentration is predicted to be below 150 μg/m 3 and the atmosphere is regarded as clear. Under very turbid conditions, the PM 10 concentration exceeds 250 μg/m 3.

  17. Development of ion-exchange collectors for monitoring atmospheric deposition of inorganic pollutants in Alaska parklands

    USGS Publications Warehouse

    Brumbaugh, William G.; Arms, Jesse W.; Linder, Greg L.; Melton, Vanessa D.

    2016-09-19

    Between 2010 and 2014, the U.S. Geological Survey completed a series of laboratory and field experiments designed to develop methodology to support the National Park Service’s long-term atmospheric pollutant monitoring efforts in parklands of Arctic Alaska. The goals of this research were to develop passive sampling methods that could be used for long-term monitoring of inorganic pollutants in remote areas of arctic parklands and characterize relations between wet and dry deposition of atmospheric pollutants to that of concentrations accumulated by mosses, specifically the stair-step, splendid feather moss, Hylocomium splendens. Mosses and lichens have been used by National Park Service managers as atmospheric pollutant biomonitors since about 1990; however, additional research is needed to better characterize the dynamics of moss bioaccumulation for various classes of atmospheric pollutants. To meet these research goals, the U.S. Geological Survey investigated the use of passive ionexchange collectors (IECs) that were adapted from the design of Fenn and others (2004). Using a modified IEC configuration, mulitple experiments were completed that included the following: (a) preliminary laboratory and development testing of IECs, (b) pilot-scale validation field studies during 2012 with IECs at sites with instrumental monitoring stations, and (c) deployment of IECs in 2014 at sites in Alaska having known or suspected regional sources of atmospheric pollutants where samples of Hylocomium splendens moss also could be collected for comparison. The targeted substances primarily included ammonium, nitrate, and sulfate ions, and certain toxicologically important trace metals, including cadmium, cobalt, copper, nickel, lead, and zinc.Deposition of atmospheric pollutants is comparatively low throughout most of Alaska; consequently, modifications of the original IEC design were needed. The most notable modification was conversion from a single-stage mixed-bed column to a two

  18. 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.

  19. 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.

  20. [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

  1. [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).

  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. Atmospheres and Interior Models

    NASA Astrophysics Data System (ADS)

    De Greve, J. P.

    Why? Recipe and Ingredients Equations Ingredients Shooting (a Solution) Evolution: From Wherefrom to Whereto, but Most of All: Why? Masses Make All the Difference Timescales Convection and Other Mixings Dredge-Up Phases in the Life of a Star Anchored Shell Sources (the Node Theorem for Active Shell Sources) Mass Motions of Different Shells Thermal Pulses or Secular Stabilities of Shell Sources Density Changes of a Nuclear Burning Zone Shell Perturbation and Pressure Change Cepheids (as an Answer to the Request of T. Le Bertre) The Period-Density Relation The Valve Mechanism The Kappa Mechanism (Baker and Kippenhahn 1962) Massive Stars (M > 9 Msun) Mass Loss by Stellar Wind Effects on the Position in the HRD The Effect of Overshooting Internal Mixing Radius Correction for Hydrostatic Stars New Models for Massive Stars

  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. 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

  6. 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.

  7. 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

  8. 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

  9. Interpretation of atmospheric pollution phenomena in relationship with the vertical atmospheric remixing by means of natural radioactivity measurements (radon) of particulate matter.

    PubMed

    Avino, Pasquale; Brocco, Domenico; Lepore, Luca; Pareti, Salvatore

    2003-01-01

    In this paper the results of seasonal monitoring campaign for primary (benzene and carbon monoxide) and secondary (nitrogen dioxide and ozone) pollutants and for the natural radioactivity of the particulate matter in the urban area of Rome, are reported to investigate acute atmospheric pollution episodes. Comparing the daily concentration trends of primary and secondary pollutants with those of the natural radioactivity, considered as index of the vertical diffusion in the low boundary layer, it has been evidenced that the acute pollution episodes in Rome occur in the winter period for the high atmospheric stability (primary pollution) and in the summer period for the strong diurnal atmospheric remixing (secondary pollution).

  10. 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.

  11. Atmospheric and wind modeling for ATC

    NASA Technical Reports Server (NTRS)

    Slater, Gary L.

    1990-01-01

    The section on atmospheric modeling covers the following topics: the standard atmosphere, atmospheric variations, atmosphere requirements for ATC, and implementation of a software model for Center/Tracon Advisory System (CTAS). The section on wind modeling covers the following topics: wind data -- NOAA profiler system; wind profile estimation; incorporation of various data types into filtering scheme; spatial and temporal variation; and software implementation into CTAS. The appendices contain Matlab codes for atmospheric routines and for wind estimation.

  12. 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.

  13. Development of ion-exchange collectors for monitoring atmospheric deposition of inorganic pollutants in Alaska parklands

    USGS Publications Warehouse

    Brumbaugh, William G.; Arms, Jesse W.; Linder, Greg L.; Melton, Vanessa D.

    2016-09-19

    (p<0.07). Exploratory models indicated linear uptake of the three metals by Hylocomium splendens moss and nonlinear uptake of sulfur from sulfate.Our results provided useful preliminary models for several of the targeted substances; however, our ability to characterize relations between concentrations in moss and loadings for many of the metals was precluded by several factors. The few test sites, small concentration gradients, and generally low concentrations hampered model developments. In addition, the weather was unusually warm throughout Alaska during the winter of 2013–14, which caused intermittent melting of the snowpack at some of the test sites; consequently, our measurements of overwinter loads based on snowpack samples (obtained in late March) probably underestimated the actual loads. Regardless of these potential limitations, these studies have established a foundation to support further studies that can improve our understanding of how mosses accumulate inorganic substances and ultimately how mosses might be used as biomonitors of atmospheric pollutants; moreover, the successful development and validation of the IECs during this research documents how the methodology can be used for future monitoring efforts in remote regions of Alaska and elsewhere.

  14. 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.

  15. 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.

  16. 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.

  17. [Temporal and spatial characteristics of atmospheric NO2 over Hainan Island and the pollutant sources in recent 10 years].

    PubMed

    Fu, Chuan-bo; Chen, You-long; Dan, Li; Tang, Jia-xiang

    2015-01-01

    The temporal-spatial characteristics of the tropospheric column NO2 (TroNO2) and total column NO2 (TotNO2) over Hainan Island are analyzed using remote sensing data derived from OMI sensor, and also combining surface wind, SO2, HYSPLIT model to research the source of atmospheric pollutants over Hainan Island. The results show that: The value of NO2 in northern area is higher than that in southern area, and the value of NO, in central mountainous area is lower than those other places. In addition, the seasonal variation of NO2 indicates that NO2 is higher in winter and lower in summer, which can be attributed to precipitation in summer and external transport of atmospheric pollutants in winter. Long-term changes of NO2 in Hainan Island appear opposite trends during winter and summer, which is declining in winter and has a weak increase in summer. The reasonable explanation is that local emissions of pollutants play an important role in summer, but external transport is the main resource of pollutants over Hainan Island. The TroNO2 in Haikou City has a good relationship with favorable delivered days in PRD, the correlation coefficient is 0.84 with 99% confidence level. Moreover, there are 3 transport paths in Dec. 2013 which can impact Haikou City from backward trajectory analysis, but all of them pass through the PRD, which can further prove that atmospheric pollutants of Hainan Island in winter are mainly delivery from PRD region.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Verification of greenhouse gas emission reductions: the prospect of atmospheric monitoring in polluted areas.

    PubMed

    Levin, Ingeborg; Hammer, Samuel; Eichelmann, Elke; Vogel, Felix R

    2011-05-28

    Independent verification of greenhouse gas emissions reporting is a legal requirement of the Kyoto Protocol, which has not yet been fully accomplished. Here, we show that dedicated long-term atmospheric measurements of greenhouse gases, such as carbon dioxide (CO(2)) and methane (CH(4)), continuously conducted at polluted sites can provide the necessary tool for this undertaking. From our measurements at the semi-polluted Heidelberg site in the upper Rhine Valley, we find that in the catchment area CH(4) emissions decreased on average by 32±6% from the second half of the 1990s until the first half of the 2000s, but the observed long-term trend of emissions is considerably smaller than that previously reported for southwest Germany. In contrast, regional fossil fuel CO(2) levels, estimated from high-precision (14)CO(2) observations, do not show any significant decreasing trend since 1986, in agreement with the reported emissions for this region. In order to provide accurate verification, these regional measurements would best be accompanied by adequate atmospheric transport modelling as required to precisely determine the relevant catchment area of the measurements. Furthermore, reliable reconciliation of reported emissions will only be possible if these are known at high spatial resolution in the catchment area of the observations. This information should principally be available in all countries that regularly report their greenhouse gas emissions to the United Nations Framework Convention on Climate Change.

  3. 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

  4. [Respiratory health of children and atmospheric pollution. I. Respiratory symptoms].

    PubMed

    Aubry, C; Teculescu, D; Chau, N; Viaggi, M N; Pham, Q T; Manciaux, M

    1989-01-01

    The impact on the respiratory system of complex industrial pollution (dust, sulphur dioxide, nitrogen oxides, hydrocarbons) was assessed by an analytical epidemiological study in a population of school children in the northeast of France. The parents of 375 children aged from 9-12 (middle school course 1 and 2) from the polluted zone and 523 children of the same age in a neighboring zone which was not polluted have filled in standardised questionnaires (respiratory symptoms, previous infections and allergies, frequency of infection in infancy; tobacco habits, professional and educational attainments of the parents, domestic environment). In the exposed children the majority of respiratory symptoms were more frequent (e.g., respiratory sounds in the boys, 15.6% against 7.9% p less than 0.01) and the absenteeism from school was more numerous (66.9% against 59.1% p less than 0.01). However, the interpretation of the results had to take into account the existence of confusing factors: parental smoking habits and the use of coal fires increased the prevalence of symptoms in the polluted zone, whereas a less crowded population worked in the inverse direction; likewise the educational level of the parents was higher in the polluted zone. After adjusting for these confusing factors, the frequency of rhinitis and absenteeism from school was significantly higher in exposed children.

  5. Atmospheric pollutants in Uludağ National Park.

    PubMed

    Tuncel, S G; Karakaş, S Y; Ozer, U

    1996-01-01

    Gas phase pollutants and major ions were measured in the Sarýalan region of Uludağ Mountain, which is experiencing severe deforestation. Short- and long-term trends in the concentration of the gas pollutants were computed from the samples obtained in order to identify the source of these pollutants. The higher concentration of O3 during summer months was consistent with the higher photochemical production from precursor gases (NOx) with increased solar flux. The diurnal pattern of O3, NO, NO2 and TSP describes a photochemical smog scenario. A lower pH in aerosols associated with high levels of SO4(2-) and NO3- is an indication of acid deposition. Wind sector analysis revealed that the major contributing source regions are north and south of the sampling site, that is, the city of Bursa, local industries, and the Orhaneli power plant.

  6. 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.

  7. 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.

  8. A chemical adsorption system for the sampling of gaseous organic pollutants in operating theatre atmospheres.

    PubMed

    Halliday, M M; Carter, K B

    1978-10-01

    The development of an air sampler and its use in measuring organic pollutants in operating theatre atmospheres are described. Air was sampled continuously during an operating session and the results obtained represent the average pollution at the sample site during that session. The technique involved the chemical adsorption of organic vapours to polymer beads and pollutants thus trapped could be stored for several days before thermal desorption and analysis by gas chromatography. The three most abundant organic pollutants were ethanol, propan-2-ol (isopropanol) and halothane.

  9. 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.

  10. 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.

  11. [Characteristics of Winter Atmospheric Mixing Layer Height in Beijing-Tianjin-Hebei Region and Their Relationship with the Atmospheric Pollution].

    PubMed

    Li, Meng; Tang, Gui-qian; Huang, Jun; Liu, Zi-rui; An, Jun-lin; Wang, Yue-si

    2015-06-01

    Atmospheric mixing layer height (MLH) is one of the main factors affecting the atmospheric diffusion and plays an important role in air quality assessment and distribution of the pollutants. Based on the ceilometers data, this paper has made synchronous observation on MLH in Beijing-Tianjin-Hebei region (Beijing, Tianjin, Shijiazhuang and Qinhuangdao) in heavy polluted February 2014 and analyzed the respective overall change and its regional features. Results show that in February 2014,the average of mixing layer height in Qinhuangdao is the highest, up to 865 +/- 268 m, and in Shijiazhuang is the lowest (568 +/- 207 m), Beijing's and Tianjin's are in between, 818 +/- 319 m and 834 +/- 334 m respectively; Combined with the meteorological data, we find that radiation and wind speed are main factors of the mixing layer height; The relationship between the particle concentration and mixing layer height in four sites suggests that mixing layer is less than 800 m, concentration of fine particulate matter in four sites will exceed the national standard (GB 3095-2012, 75 microg x m(-3)). During the period of observation, the proportion of days that mixing layer is less than 800 m in Beijing, Tianjin, Shijiazhuang and Qinhuangdao are 50%, 43%, 80% and 50% respectively. Shijiazhuang though nearly formation contaminant concentration is high, within the atmospheric mixed layer pollutant load is not high. Unfavorable atmospheric diffusion conditions are the main causes of heavy pollution in Shijiazhuang for a long time. The results of the study are of great significance for cognitive Beijing-Tianjin-Hebei area pollution distribution, and can provide a scientific reference for reasonable distribution of regional pollution sources.

  12. 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

  13. 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.

  14. 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.).

  15. 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).

  16. Central Arctic Atmospheric SO2 pollution from smelters: Airborne detection and Arctic Haze formation

    NASA Astrophysics Data System (ADS)

    Arnold, F.; Nau, R.; Jurkat, T.; Schlager, H.; Minikin, A.; Dörnbrack, A.; Pirjola, L.; Stohl, A.

    2009-04-01

    Arctic Haze represents a dramatic manifestation of anthropogenic pollution of a remote and previously pristine atmospheric environment, which presently experiences faster climate warming than any other region on the planet. Arctic haze influences visibility, ecosystems, and may contribute to Arctic climate warming. In spring, Arctic Haze occupies large parts of the Arctic lower troposphere, the so called Arctic Dome. The most abundant Arctic Haze component is sulphate, which was previously thought to stem preferably from Extra-Arctic anthropogenic pollution sources. However, recent model simulations suggest that sulphate particle transport into the Arctic Dome is severely hindered. During the recent POLAR YEAR 2007/2008, in 2007, we have made the first Central Arctic SO2 measurements with high vertical and horizontal resolution and detected SO2 rich pollution plumes in the entire troposphere height range up to 9000 m. Below 2000 m, inside the Arctic Dome, these plumes were most pronounced and stemmed preferably from a giant Ni-Cu smelter complex, located in the Siberian sector of the Arctic Dome, near the city Norilsk, at a distance of 2100 km from our measurement region. Our measurements and accompanying model simulations indicate that SO2 emitted by that smelter complex represents a mayor if not the dominant precursor of Arctic Dome cloud condensation nuclei and haze particles. Along with SO2, were measured aerosol particles and additional trace gases including also gas-phase NOy (sum of reactive nitrogen gases). Importantly, the abundance ratio R=SO2/NOy is quite different for different SO2 source types (about 1-2 for fossil fuel combustion, <0.1 for bio mass burning, and about 40 for Ni/Cu smelting) and therefore serves as an SO2-source marker. In addition to our air craft measurements, we have made accompanying model simulations of pollutant transport and aerosol formation and growth. Our air craft measurements were part of the ASTAR 2007 (ASTAR=Arctic Study

  17. Atmospheric millimeter wave propagation model

    NASA Astrophysics Data System (ADS)

    Liebe, H. J.

    1983-12-01

    The neutral atmosphere is characterized for the frequency range from 1 to 300 GHz as nonturbulent propagation medium. Attenuation and propagation delay effects are predicated from meteorological data sets: pressure, temperature, humidity, suspended particle concentration, and rain rate. The physical data base of the propagation model consists of four terms: (1) resonance information for 30 water vapor and 48 oxygen absorption lines in the form of intensity coefficients and center frequency for each line; (2) a composite (oxygen, water vapor, and nitrogen) continum spectrum; (3) a hydrosol attenuation term for haze, fog, and cloud conditions; and (4) a rain attenuation model. Oxygen lines extend into the mesosphere, where they behave in a complicated manner due to the Zeeman effect.

  18. A Atmospheric Dispersion Model for the Sudbury, Ontario, Area.

    NASA Astrophysics Data System (ADS)

    Huhn, Frank Jones

    1982-03-01

    A mathematical model was developed and tested to predict the relationship between sulphur oxide and trace metal emissions from smelters in the Sudbury, Ontario area, and atmospheric, precipitation, lake water and sediment chemistry. The model consists of atmospheric and lake chemistry portions. The atmospheric model is a Gaussian crosswind concentration distribution modification to a box model with a uniform vertical concentration gradient limited by a mixing height. In the near-field Briggs' plume rise and vertical dispersion terms are utilized. Oxidation, wet and dry deposition mechanisms are included to account for the gas, liquid and solid phases separately. Important improvements over existing models include (1) near- and far-field conditions treated in a single model; (2) direct linkage of crosswind dispersion to hourly meteorological observations; (3) utilization of maximum to minimum range of input parameters to realistically model the range of outputs; (4) direct linkage of the atmospheric model to a lake model. Precipitation chemistry as calculated by the atmospheric model is related to lake water and sediment chemistry utilizing a mass balance approach and assuming a continuously stirred reactor (CSTR) model to describe lake circulation. All inputs are atmospheric, modified by hydrology, soil chemistry and sedimentation. Model results were tested by comparison with existing atmospheric and precipitation chemistry measurements, supplemented with analyses of lake water and sediment chemistry collected in a field program. Eight pollutant species were selected for modeling: sulphur dioxide, sulphate ion, hydrogen ion, copper, nickel, lead, zinc, and iron. The model effectively predicts precipitation chemistry within 150 km of Sudbury, with an average prediction to measurement ratio of 90 percent. Atmospheric concentrations are effectively predicted within 80 km, with an average prediction to measurement ratio of 81 percent. Lake chemistry predictions are

  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. Biomonitoring of the atmospheric pollution by heavy metals in Morocco

    NASA Astrophysics Data System (ADS)

    Gaudry, A.; Senhou, A.; Chouak, A.; Cherkaoui, R.; Moutia, Z.; Lferde, M.; Elyahyaoui, A.; El Khoukhi, T.; Bounakhla, M.; Embarch, K.; Ayrault, S.; Moskura, M.

    2003-05-01

    In this study, the accumulation sensitivities of trace elements in six types of air pollution biomonitors (lichens, tree barks and a moss) are compared. Three analytical methods were used:14MeV neutron activation analysis, thermal neutron activation analysis method and X-ray fluorescence analysis. Studies of the local concentration variations versus the sizes of lichen and of their altitude of collection from grounds, revealed that a standardisation of the procedures for collecting samples was necessary.

  2. Atmospheric transport and deposition of acidic air pollutants

    SciTech Connect

    Murphy, C.E. Jr.

    1981-01-01

    Although general principles which govern atmospheric chemistry of sulfur are understood, a purely theoretical estimation of the magnitude of the processes is not likely to be useful. Furthermore, the data base necessary to make empirical estimates does not yet exist. The sulfur budget of the atmosphere appears to be dominated by man-associated sulfur. The important processes in deposition of man-associated sulfur are wet deposition of sulfate and dry deposition of SO/sub 2/. The relative importance of sulfate and SO/sub 2/ to sulfur deposition (input to watersheds) depends on the air concentrations, and either compound may be the greater contributor depending on conditions. (PSB)

  3. 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…

  4. Atmospheric neutrino flux calculation using the NRLMSISE-00 atmospheric model

    NASA Astrophysics Data System (ADS)

    Honda, M.; Athar, M. Sajjad; Kajita, T.; Kasahara, K.; Midorikawa, S.

    2015-07-01

    We extend our calculation of the atmospheric neutrino fluxes to polar and tropical regions. It is well known that the air density profiles in the polar and the tropical regions are different from the mid-latitude region. Also there are large seasonal variations in the polar region. In this extension, we use the NRLMSISE-00 global atmospheric model J. M. Picone, J. Geophys. Res. 107, SIA 15 (2002), replacing the U.S.-standard 1976 atmospheric model, which has no positional or seasonal variations. With the NRLMSISE-00 atmospheric model, we study the atmospheric neutrino flux at the polar and tropical regions with seasonal variations. The geomagnetic model international geomagnetic reference field (IGRF) we have used in our calculations seems accurate enough in the polar regions also. However, the polar and the equatorial regions are the two extremes in the IGRF model, and the magnetic field configurations are largely different from one another. Note that the equatorial region is also the tropical region generally. We study the effect of the geomagnetic field on the atmospheric neutrino flux in these extreme regions.

  5. 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.

  6. 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.

  7. Powerplant Thermal-Pollution Models

    NASA Technical Reports Server (NTRS)

    Lee, S. S.; Sengupta, S.

    1982-01-01

    Three models predict nature of thermal plumes from powerplant discharge into water. Free-surface model accomodates major changes in ocean currents. Rigid-model accurately predicts changes in thermal plume caused by other inputs and outputs, such as pumped-water storage and hydroelectric-plant discharges. One-dimensional model predicts approximate stratification in lake with such inputs and outputs over a long period.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. 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

  16. [Long-distance transportation of atmospheric pollutants and its effects on ecosystems].

    PubMed

    Guardans, R; Gimeno, B S

    1994-01-01

    It was known, as far back as the nineteenth century, that rain water from industrial areas was more acid than that from rural areas. The potential risks for life in general were discussed, but no further attention was paid to the issue. At the end of the twentieth century, the ecosystems of Europe, Canada and the United States have been severely damaged by pollutants borne by atmospheric winds to places distant from their origin. The main effects of these atmospheric pollutants are due to sulfur and nitrogen oxide dilution and to photochemical reactions. International organizations have been formed and agreements pronounced and ratified by many countries for a universal study on the pollution process, on the transport of pollutants--mostly sulfur, nitrogen and ozone--and on how to collaborate in order to reduce emissions in the respective countries of origin for the worldwide profit.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. [Measurement of atmospheric boundary layer pollutants by mobile lidar in Beijing].

    PubMed

    Wang, Shao-Lin; Xie, Pin-Hua; Hu, Shun-Xing; Wei, He-Li; Hu, Huan-Ling; Xie, Jun; Cao, Kai-Fa; Fang, Xin

    2008-03-01

    The parameters of AML-2 mobile lidar were introduced, which was based on differential absorption principle and designed by our institute. In Yufa of Beijing, the pollutants including O3, NO2, SO2 in atmospheric boundary layer were monitored in August and September of 2006 under different weather conditions. Vertical profile and diurnal variation of concentrations of these pollutants were analyzed. If without the influence of pollution air transport from south region, the concentrations of these pollutants are low under the overcast weather condition. The concentrations of O3 and NO2 decrease with altitude, and this characteristic is not obvious for SO2, but there is a high concentration layer of SO2 near ground (about 0.6km). The quality of atmosphere Beijing is influenced significantly by air transportation from south region, and the altitude of the severe pollution air transport is about 1km to 1.5km in August 23rd to 25th. As a result, the characteristics of vertical profile and daily variation of the pollutants are changed, and the concentrations of O3, NO2, SO2 in atmospheric boundary layer of Yufa area increased obviously.

  2. Modeling diffuse pollution with a distributed approach.

    PubMed

    León, L F; Soulis, E D; Kouwen, N; Farquhar, G J

    2002-01-01

    The transferability of parameters for non-point source pollution models to other watersheds, especially those in remote areas without enough data for calibration, is a major problem in diffuse pollution modeling. A water quality component was developed for WATFLOOD (a flood forecast hydrological model) to deal with sediment and nutrient transport. The model uses a distributed group response unit approach for water quantity and quality modeling. Runoff, sediment yield and soluble nutrient concentrations are calculated separately for each land cover class, weighted by area and then routed downstream. The distributed approach for the water quality model for diffuse pollution in agricultural watersheds is described in this paper. Integrating the model with data extracted using GIS technology (Geographical Information Systems) for a local watershed, the model is calibrated for the hydrologic response and validated for the water quality component. With the connection to GIS and the group response unit approach used in this paper, model portability increases substantially, which will improve non-point source modeling at the watershed scale level.

  3. 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

  4. Regional atmospheric composition modeling with CHIMERE

    NASA Astrophysics Data System (ADS)

    Menut, L.; Bessagnet, B.; Khvorostyanov, D.; Beekmann, M.; Colette, A.; Coll, I.; Curci, G.; Foret, G.; Hodzic, A.; Mailler, S.; Meleux, F.; Monge, J.-L.; Pison, I.; Turquety, S.; Valari, M.; Vautard, R.; Vivanco, M. G.

    2013-01-01

    Tropospheric trace gas and aerosol pollutants have adverse effects on health, environment and climate. In order to quantify and mitigate such effects, a wide range of processes leading to the formation and transport of pollutants must be considered, understood and represented in numerical models. Regional scale pollution episodes result from the combination of several factors: high emissions (from anthropogenic or natural sources), stagnant meteorological conditions, velocity and efficiency of the chemistry and the deposition. All these processes are highly variable in time and space, and their relative importance to the pollutants budgets can be quantified within a chemistry-transport models (CTM). The offline CTM CHIMERE model uses meteorological model fields and emissions fluxes and calculates deterministically their behavior in the troposphere. The calculated three-dimensional fields of chemical concentrations can be compared to measurements to analyze past periods or used to make air quality forecasts and CHIMERE has enabled a fine understanding of pollutants transport during numerous measurements campaigns. It is a part of the PREVAIR french national forecast platform, delivering pollutant concentrations up to three days in advance. The model also allows scenario studies and long term simulations for pollution trends. The modelling of photochemical air pollution has reached a good level of maturity, and the latest projects involving CHIMERE now aim at increasing our understanding of pollution impact on health at the urban scale or at the other end of the spectrum for long term air quality and climate change interlinkage studies, quantifying the emissions and transport of pollen, but also, at a larger scale, analyzing the transport of pollutants plumes emitted by volcanic eruptions and forest fires.

  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. 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…

  7. Atmospheric input of organic pollutants to the Venice Lagoon.

    PubMed

    Rossini, P; De Lazzari, A; Guerzoni, S; Molinaroli, E; Rampazzo, G; Zancanaro, A

    2001-01-01

    The atmospheric deposition of dioxins and furans (PCDD-Fs), dioxin-like polychlorobyphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and hexachlorobenzene (HCB) was determined in the Lagoon of Venice. Sampling was carried out monthly, for a total of 13 months (July 1998-July 1999) using "bulk" samplers (passive collectors of wet and dry depositions) at four sites, inside the lagoon and close to its edge. Calculated PCDD-F loadings to the Lagoon turned out to be quite homogeneous, their range being approximately 10-20 ng m-2 y-1, whereas in the station located close to the industrial zone of Porto Marghera the value was approximately 50 ng m-2 y-1. PCB deposition in the industrial fallout sampling site and in the city centre of Venice was approximately 2500 ng m-2 y-1, that is, almost five times higher than the values measured at the northern and southern lagoon stations. HCB annual loading (approximately 8000 ng m-2 y-1) was almost six times higher in the industrial zone than in the other sites (approximately 1500 ng m-2 y-1). PAH loadings in the city centre of Venice and at Porto Marghera were 314 and 389 micrograms m-2 y-1, respectively. The amount of 2,3,7,8-TCDD equivalents (TEQ) of PCDD-Fs and PCBs in the Venice and Porto Marghera bulk depositions was compared with the guideline value of 15 pg m-2 d-1 for dioxins in depositions proposed by De Fré et al. (1998). Moreover, as some of the effects which drive the risk assessment of dioxin-like compounds were also observed after exposure to other molecules, the TEQs of PAHs and HCB were also calculated: nine out of 13 samples exceeded the guideline value. Lastly, an atmospheric emission source related to vinyl chloride monomer production, which may affect atmospheric deposition on the whole Lagoon, is reported in the industrial zone of Porto Marghera.

  8. 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.

  9. 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.

  10. Forecasting long-range atmospheric pollutant transport and dispersion: Approaches and issues

    SciTech Connect

    Griggs, D.P.; Addis, R.P.

    1996-01-11

    The ability to forecast the transport and diffusion of airborne contaminants over long distances is vital when responding to nuclear emergencies. Increases in computing capabilities and ready access to large-scale model output make it possible to employ advanced three-dimensional prognostic models to forecast the long-range transport of toxic or radioactive gases for emergency response. The Savannah River Technology Center (SRTC) of the U.S. Department of Energy`s Savannah River Site demonstrated this during the European Tracer EXperiment (ETEX). ETEX, conducted in the Fall of 1994, is designed to evaluate the performance of models for long-range atmospheric pollutant transport and dispersion. ETEX involved two tracer experiments as well as a multinational real-time modeling exercise. The real-time modeling component tested the ability of participants to provide timely long-range forecasts of the tracer plume transport and diffusion. Notification of the time, location and amount of tracer occurred after the start of the release. Participants provided 60-hour forecasts of tracer surface concentration within 6 hours of being notified, and updated forecasts every 12 hours thereafter. The two tracer experiments were conducted near Rennes, France on October 23, 1994 and November 14, 1994.

  11. Extensive regional atmospheric hydrocarbon pollution in the southwestern United States.

    PubMed

    Katzenstein, Aaron S; Doezema, Lambert A; Simpson, Isobel J; Blake, Donald R; Rowland, F Sherwood

    2003-10-14

    Light alkane hydrocarbons are present in major quantities in the near-surface atmosphere of Texas, Oklahoma, and Kansas during both autumn and spring seasons. In spring 2002, maximum mixing ratios of ethane [34 parts per 109 by volume (ppbv)], propane (20 ppbv), and n-butane (13 ppbv) were observed in north-central Texas. The elevated alkane mixing ratios are attributed to emissions from the oil and natural gas industry. Measured alkyl nitrate mixing ratios were comparable to urban smog values, indicating active photochemistry in the presence of nitrogen oxides, and therefore with abundant formation of tropospheric ozone. We estimate that 4-6 teragrams of methane are released annually within the region and represents a significant fraction of the estimated total U.S. emissions. This result suggests that total U.S. natural gas emissions may have been underestimated. Annual ethane emissions from the study region are estimated to be 0.3-0.5 teragrams.

  12. Biomonitoring persistent organic pollutants in the atmosphere with mosses: performance and application.

    PubMed

    Wu, Qimei; Wang, Xin; Zhou, Qixing

    2014-05-01

    Persistent organic pollutants (POPs) have aroused environmentalists and public concerns due to their toxicity, bioaccumulation and persistency in the environment. However, monitoring atmospheric POPs using conventional instrumental methods is difficult and expensive, and POP levels in air samples represent an instantaneous value at a sampling time. Biomonitoring methods can overcome this limitation, because biomonitors can accumulate POPs, serve as long-term integrators of POPs and provide reliable information to assess the impact of pollutants on the biota and various ecosystems. Recently, mosses are increasingly employed to monitor atmospheric POPs. Mosses have been applied to indicate POP pollution levels in the remote continent of Antarctica, trace distribution of POPs in the vicinity of pollution sources, describe the spatial patterns at the regional scale, and monitor the changes in the pollution intensity along time. In the future, many aspects need to be improved and strengthened: (i) the relationship between the concentrations of POPs in mosses and in the atmosphere (different size particulates and vapor phases); and (ii) the application of biomonitoring with mosses in human health studies.

  13. 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...

  14. Tracing combustion-derived atmospheric pollutants using compound-specific isotope analysis

    NASA Astrophysics Data System (ADS)

    Ballentine, Donna Christine

    1997-04-01

    The use of compound specific carbon isotopic analysis (CSIA) has been investigated as a means to trace the origin and fate of organic pollutants in the atmosphere. Polycyclic aromatic hydrocarbons (PAH) and fatty acids have been suggested as two chemical classes which may serve as suitable molecular markers for anthropogenic combustion processes, such as fossil fuel combustion and biomass burning, that introduce significant quantities of organic pollutants into the atmospheric environment. First, analytical procedures for the extraction and isolation of these compounds from particulate aerosols, as well as a description of the isotopic measurement techniques, have been presented. Second, the precision and accuracy of these methods and measurements have been demonstrated. Third, the isotopic variability of PAH and fatty acids produced from different combustion processes has been investigated. In addition, in order to demonstrate the applicability of this technique as a means to monitor the fate of atmospheric pollutants, isotopic measurements of PAH, fatty acids, and alkanes isolated from a series of ambient aerosol samples have been made in a preliminary attempt to determine if compound specific isotope analysis of molecular markers in aerosols can be used in conjunction with other chemical and atmospheric data in order to reflect the transport of pollution episodes.

  15. 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.

  16. [Atmospheric asbestos pollution in the urban environment: Milan, Casale Monferrato, Brescia, Ancona, Bologna and Florence].

    PubMed

    Chiappino, G; Sebastien, P; Todaro, A

    1991-01-01

    The atmospheric concentrations of asbestos fibres were measured in 6 towns by long term sampling of air (3 weeks) and by counting at TEM both long and short fibres. Chrisotile and amphiboles were separately counted. For each town high traffic, low traffic and no traffic zones were considered as well as industrial areas and areas with possible and probable sources of asbestos pollution. For Milano the seasonal variations in atmospheric concentrations of asbestos fibres were also recorded in a central square. The maximum concentrations of total fibres was found in Milano (251.7 fibres/liter) and the minimum in Bologna (0.3 fibres/liter). Chrisotile and ultrashort fibres are the most frequent component of the atmospheric pollution. The fibre counts to which people is exposed are far below the levels at which it has been possible to detect risks in industry: however the possibility of a synergism between asbestos and other pollutants with consequent increase of the total carcinogenic potential of the polluted atmosphere cannot be ruled out. The control of the most active sources of asbestos dispersion must be considered in a correct balance between costs and social benefits.

  17. The Mobile Atmospheric Pollutant Mapping (MAPM) System - A coherent CO2, DIAL system

    NASA Technical Reports Server (NTRS)

    Grant, William B.

    1989-01-01

    The hardware for the Mobile Atmospheric Pollutant Mapping System is described. Measurement results using the hardware are reported along with absorption coefficients and measurement sensitivities for a number of molecular species. The factor that limit measurement accuracy and range are considered.

  18. Current and future levels of mercury atmospheric pollution on a global scale

    NASA Astrophysics Data System (ADS)

    Pacyna, Jozef M.; Travnikov, Oleg; De Simone, Francesco; Hedgecock, Ian M.; Sundseth, Kyrre; Pacyna, Elisabeth G.; Steenhuisen, Frits; Pirrone, Nicola; Munthe, John; Kindbom, Karin

    2016-10-01

    An assessment of current and future emissions, air concentrations, and atmospheric deposition of mercury worldwide is presented on the basis of results obtained during the performance of the EU GMOS (Global Mercury Observation System) project. Emission estimates for mercury were prepared with the main goal of applying them in models to assess current (2013) and future (2035) air concentrations and atmospheric deposition of this contaminant. The combustion of fossil fuels (mainly coal) for energy and heat production in power plants and in industrial and residential boilers, as well as artisanal and small-scale gold mining, is one of the major anthropogenic sources of Hg emissions to the atmosphere at present. These sources account for about 37 and 25 % of the total anthropogenic Hg emissions globally, estimated to be about 2000 t. Emissions in Asian countries, particularly in China and India, dominate the total emissions of Hg. The current estimates of mercury emissions from natural processes (primary mercury emissions and re-emissions), including mercury depletion events, were estimated to be 5207 t year-1, which represents nearly 70 % of the global mercury emission budget. Oceans are the most important sources (36 %), followed by biomass burning (9 %). A comparison of the 2035 anthropogenic emissions estimated for three different scenarios with current anthropogenic emissions indicates a reduction of these emissions in 2035 up to 85 % for the best-case scenario. Two global chemical transport models (GLEMOS and ECHMERIT) have been used for the evaluation of future mercury pollution levels considering future emission scenarios. Projections of future changes in mercury deposition on a global scale simulated by these models for three anthropogenic emissions scenarios of 2035 indicate a decrease in up to 50 % deposition in the Northern Hemisphere and up to 35 % in Southern Hemisphere for the best-case scenario. The EU GMOS project has proved to be a very important

  19. Formaldehyde in the ambient atmosphere: from an indoor pollutant to an outdoor pollutant?

    PubMed

    Salthammer, Tunga

    2013-03-18

    Formaldehyde has been discussed as a typical indoor pollutant for decades. Legal requirements and ever-lower limits for formaldehyde in indoor air have led to a continual reduction in the amount of formaldehyde released from furniture, building materials, and household products over many years. Slowly, and without much attention from research on indoor air, a change of paradigm is taking place, however. Today, the formaldehyde concentrations in outdoor air, particularly in polluted urban areas, sometimes already reach indoor levels. This is largely a result of photochemical processes and the use of biofuels. In the medium term, this development might have consequences for the way buildings are ventilated and lead to a change in the way we evaluate human exposure.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. The CIFIST 3D model atmosphere grid.

    NASA Astrophysics Data System (ADS)

    Ludwig, H.-G.; Caffau, E.; Steffen, M.; Freytag, B.; Bonifacio, P.; Kučinskas, A.

    Grids of stellar atmosphere models and associated synthetic spectra are numerical products which have a large impact in astronomy due to their ubiquitous application in the interpretation of radiation from individual stars and stellar populations. 3D model atmospheres are now on the verge of becoming generally available for a wide range of stellar atmospheric parameters. We report on efforts to develop a grid of 3D model atmospheres for late-type stars within the CIFIST Team at Paris Observatory. The substantial demands in computational and human labor for the model production and post-processing render this apparently mundane task a challenging logistic exercise. At the moment the CIFIST grid comprises 77 3D model atmospheres with emphasis on dwarfs of solar and sub-solar metallicities. While the model production is still ongoing, first applications are already worked upon by the CIFIST Team and collaborators.

  5. Modelling the dispersion of vehicle-emitted pollutants

    SciTech Connect

    McCrae, I.S.; Hamilton, R.S.; Revitt, D.M. ); Harrop, D.O. )

    1988-01-01

    It is well known that certain vehicle-generated air pollutants may have adverse effects on human health, ecosystems and amenity. For many years, carbon monoxide and lead were the pollutants which received most attention. However, other problems have been identified, principally the role of nitrogen oxides in producing acid rain, the mutagenic and carcinogenic effects of polyaromatic hydrocarbons and the darkness of diesel-emitted smoke. The magnitude of some of the problems has been compounded by changes in engine design and fuel composition. An understanding of the impact of vehicle-emitted pollutants on the environment requires a knowledge of the processes which control their transport through the atmosphere. Short-range transport processes are best investigated using field data collected near to a rural motorway since in that situation the source is a well-defined line to which standard mathematical modelling techniques can be applied and non-vehicle sources of pollution are reduced to a minimum. This paper examines the use of desk-top and computer-based techniques to predict CO concentrations.

  6. 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.

  7. 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.

  8. A method for sampling dimethylsulfide in polluted and remote marine atmospheres

    NASA Astrophysics Data System (ADS)

    Davison, Brian M.; Allen, Andrew G.

    Methods have been developed for the measurement of atmospheric dimethylsulfide in both polluted and clean marine environments, avoiding Sampling losses due to reactions with atmospheric oxidants. Preconcentration of DMS on Molecular Sieve 5A was followed by analysis using gas chromatography with flame photometric detection. Prolonged contact of polluted air samples with a potassium iodide-based solution resulted in total oxidant destruction. Dimethylsulfide was measured over the Atlantic Ocean during a cruise between the U.K. and the Antarctic, between October 1992 and January 1993. In equatorial regions (30° N-30° S) the atmospheric DMS concentration ranged from 5 to 90 ng m -3 with an average of 30 ng m -3 In the polar waters and regions south of the Falkland Islands concentrations from 5 to 1050 ng m -3 were observed with a mean concentration of 120 ng m -3

  9. 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

  10. Methodological approach in determination of small spatial units in a highly complex terrain in atmospheric pollution research: the case of Zasavje region in Slovenia.

    PubMed

    Kukec, Andreja; Boznar, Marija Z; Mlakar, Primoz; Grasic, Bostjan; Herakovic, Andrej; Zadnik, Vesna; Zaletel-Kragelj, Lijana; Farkas, Jerneja; Erzen, Ivan

    2014-05-01

    The study of atmospheric air pollution research in complex terrains is challenged by the lack of appropriate methodology supporting the analysis of the spatial relationship between phenomena affected by a multitude of factors. The key is optimal design of a meaningful approach based on small spatial units of observation. The Zasavje region, Slovenia, was chosen as study area with the main objective to investigate in practice the role of such units in a test environment. The process consisted of three steps: modelling of pollution in the atmosphere with dispersion models, transfer of the results to geographical information system software, and then moving on to final determination of the function of small spatial units. A methodology capable of designing useful units for atmospheric air pollution research in highly complex terrains was created, and the results were deemed useful in offering starting points for further research in the field of geospatial health.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  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. Atmospheric Particulate Matter Pollution During The 2008 Beijing Olympics

    NASA Astrophysics Data System (ADS)

    Wang, W.; Primbs, T.; Tao, S.; Zhu, T.; Simonich, S. M.

    2009-05-01

    To assess the particulate matter (PM) pollution during the 2008 Beijing Olympic games, size fractionated PM samples of >PM10, PM2.5-PM10, and

  17. 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

  18. 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

  19. 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.

  20. 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.

  1. [Acid fog: hygiene and health observations correlated with an aspect of atmospheric pollution].

    PubMed

    Gilli, G; Bono, R; Scursatone, E; Carraro, E

    1989-01-01

    In the last years the interest about acid depositions has been shifted to heterogeneous phase reactions and, particularly, to occult precipitations (fog, mist, ecc.). It is very improbable that some kind of human health hazards could derive from acid rain exposure. Instead, the human exposure to acid fog could represent a possible respiratory vehicle for the assumption of acid pollutants as well as of many other pollutants. This last assertion can be supported by the following considerations: 1) Fog may represent an important chemical reactor that can modify the nature of pollutant material in the atmosphere (acidification and other events). 2) Fog is formed near the ground where pollution sources are located so that pollution is the heaviest. The fog water droplets coalesce around preexisting aerosol which is most highly concentrated near the ground (cities and industrial areas). Since fog water droplets contain muc less water than rain drops, they do not dilute the acidity as much as rain. 3) Finally, fog is partially inhalable. In certain areas of the world, wet deposition by fog can be important to the human health, even if the acqueous concentrations of fog droplets, the acidity per volume of air and the acid deposition rate are all important factors to consider. Particularly the pH of fog does not tell the whole story, but it represents a sufficient information about the severity of the atmospheric situation that can be correlated to seriousness of human risk.

  2. 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.

  3. [Characteristics of atmospheric pollutants during the period of summer and autumn in Shijiazhuang].

    PubMed

    Du, Wu-peng; Wang, Yue-si; Song, Tao; Xin, Jin-yuan; Cheng, Yi-song; Ji, Dong-sheng

    2010-07-01

    Atmospheric pollutants and their concentration change characteristics during Beijing Olympics in Shijiazhuang were studied. Air quality was measured by automatic on-line continuous monitoring equipments in summer and autumn of 2007 and 2008. The objectives of this study were to identify the effect of pollutants decrease on atmospheric environment, and develop the potential influence to Beijing and surrounding areas. The results show that the pollutants concentration often exceeds state criterion except nitrogen oxides, O3 concentration in summer and autumn is higher, averaged hourly maximum concentration (O3-Max) is (177.2 +/- 63.0) and (105.8 +/- 61.7) microg x m(-3), the concentrations of NO and NO2 are (4.5 +/- 4.0), (32.7 +/- 12.4) microg x m(-3) and (21.5 +/- 16.9), (60.5 +/- 16.9) microg x m(-3) respectively, SO2 concentration is (72.0 +/- 27.5) and (92.0 +/- 44.4) microg x m(-3), PM2.5 and PM10 concentrations reach to (102.3 +/- 47.6), (153.3 +/- 58.3) microg x m(-3) and (95.8 +/- 50.0), (147.4 +/- 67.0) microg x m(-3). Generally, pollutants declined obviously in Olympics period, the concentrations of NOx, O3-Max, SO2, PM2.5 and PM10 are (43.8 +/- 15.0), (142.0 +/- 54.9), (52.4 +/- 18.8), (76.7 +/- 35.1) and (116.5 +/- 38.8) microg x m(-3), and the reduction ratio of SO2, PM2.5 and PM10 are 34.6%, 22.8% and 21.0% compared with the whole monitoring period in 2008. The actuality of atmospheric pollution in summer and autumn was analyzed systemically, and which provided scientific evidences for evaluating the control measures of pollutants emission.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. A 3D model of Pluto's atmosphere

    NASA Astrophysics Data System (ADS)

    Vangvichith, M.; Forget, F.; Wordsworth, R.

    2011-10-01

    For the first time, we have built a GCM of Pluto's atmosphere, adapted from the model of Triton's, recently developed[9] . In fact, Pluto and Triton have a lot of similarities (atmospheric, orbital). This GCM will allow to better understand the complex mechanism of the planet and to study the variation of the thermal profile during time.

  10. ATMOSPHERIC DEPOSITION MODELING AND MONITORING OF NUTRIENTS

    EPA Science Inventory

    This talk presents an overview of the capabilities and roles that regional atmospheric deposition models can play with respect to multi-media environmental problems. The focus is on nutrient deposition (nitrogen). Atmospheric deposition of nitrogen is an important contributor to...

  11. Modeling the atmospheric chemistry of TICs

    NASA Astrophysics Data System (ADS)

    Henley, Michael V.; Burns, Douglas S.; Chynwat, Veeradej; Moore, William; Plitz, Angela; Rottmann, Shawn; Hearn, John

    2009-05-01

    An atmospheric chemistry model that describes the behavior and disposition of environmentally hazardous compounds discharged into the atmosphere was coupled with the transport and diffusion model, SCIPUFF. The atmospheric chemistry model was developed by reducing a detailed atmospheric chemistry mechanism to a simple empirical effective degradation rate term (keff) that is a function of important meteorological parameters such as solar flux, temperature, and cloud cover. Empirically derived keff functions that describe the degradation of target toxic industrial chemicals (TICs) were derived by statistically analyzing data generated from the detailed chemistry mechanism run over a wide range of (typical) atmospheric conditions. To assess and identify areas to improve the developed atmospheric chemistry model, sensitivity and uncertainty analyses were performed to (1) quantify the sensitivity of the model output (TIC concentrations) with respect to changes in the input parameters and (2) improve, where necessary, the quality of the input data based on sensitivity results. The model predictions were evaluated against experimental data. Chamber data were used to remove the complexities of dispersion in the atmosphere.

  12. GLOBAL REFERENCE ATMOSPHERIC MODELS FOR AEROASSIST APPLICATIONS

    NASA Technical Reports Server (NTRS)

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

    2005-01-01

    Aeroassist is a broad category of advanced transportation technology encompassing aerocapture, aerobraking, aeroentry, precision landing, hazard detection and avoidance, and aerogravity assist. The eight destinations in the Solar System with sufficient atmosphere to enable aeroassist technology are Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Saturn's moon Titan. Engineering-level atmospheric models for five of these targets - Earth, Mars, Titan, Neptune, and Venus - have been developed at NASA's Marshall Space Flight Center. These models are useful as tools in mission planning and systems analysis studies associated with aeroassist applications. The series of models is collectively named the Global Reference Atmospheric Model or GRAM series. An important capability of all the models in the GRAM series is their ability to simulate quasi-random perturbations for Monte Carlo analysis in developing guidance, navigation and control algorithms, for aerothermal design, and for other applications sensitive to atmospheric variability. Recent example applications are discussed.

  13. Model atmospheres, predicted spectra, and colors

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Theoretical models of stellar atmospheres and the process of forming a spectrum are reviewed with particular reference to the spectra of B stars. In the case of classical models the stellar atmosphere is though to consist of plane parallel layers of gas in which radiative and hydrostatic equilibrium exists. No radiative energy is lost or gained in the model atmosphere, but the detailed shape of the spectrum is changed as a result of the interactions with the ionized gas. Predicted line spectra using statistical equilibrium local thermodynamic equilibrium (LTE), and non-LTE physics are compared and the determination of abundances is discussed. The limitations of classical modeling are examined. Models developed to demonstrate what motions in the upper atmosphere will do to the spectrum and to explore the effects of using geometries different from plane parallel layer are reviewed. In particular the problem of radiative transfer is addressed.

  14. Atmospheric pollution history at Linfen (China) uncovered by magnetic and chemical parameters of sediments from a water reservoir.

    PubMed

    Ma, Mingming; Hu, Shouyun; Cao, Liwan; Appel, Erwin; Wang, Longsheng

    2015-09-01

    We studied magnetic and chemical parameters of sediments from sediments of a water reservoir at Linfen (China) in order to quantitatively reconstruct the atmospheric pollution history in this region. The results show that the main magnetic phases are magnetite and maghemite originating from the surrounding catchment and from anthropogenic activities, and there is a significant positive relationship between magnetic concentration parameters and heavy metals concentrations, indicating that magnetic proxies can be used to monitor the anthropogenic pollution. In order to uncover the atmospheric pollution history, we combined the known events of environmental improvement with variations of magnetic susceptibility (χ) and heavy metals along the cores to obtain a detailed chronological framework. In addition, air comprehensive pollution index (ACPI) was reconstructed from regression equation among magnetic and chemical parameters as well as atmospheric monitoring data. Based on these results, the atmospheric pollution history was successfully reconstructed.

  15. 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

  16. [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

  17. Using an epiphytic moss to identify previously unknown sources of atmospheric cadmium pollution.

    PubMed

    Donovan, Geoffrey H; Jovan, Sarah E; Gatziolis, Demetrios; Burstyn, Igor; Michael, Yvonne L; Amacher, Michael C; Monleon, Vicente J

    2016-07-15

    Urban networks of air-quality monitors are often too widely spaced to identify sources of air pollutants, especially if they do not disperse far from emission sources. The objectives of this study were to test the use of moss bio-indicators to develop a fine-scale map of atmospherically-derived cadmium and to identify the sources of cadmium in a complex urban setting. We collected 346 samples of the moss Orthotrichum lyellii from deciduous trees in December, 2013 using a modified randomized grid-based sampling strategy across Portland, Oregon. We estimated a spatial linear model of moss cadmium levels and predicted cadmium on a 50m grid across the city. Cadmium levels in moss were positively correlated with proximity to two stained-glass manufacturers, proximity to the Oregon-Washington border, and percent industrial land in a 500m buffer, and negatively correlated with percent residential land in a 500m buffer. The maps showed very high concentrations of cadmium around the two stained-glass manufacturers, neither of which were known to environmental regulators as cadmium emitters. In addition, in response to our findings, the Oregon Department of Environmental Quality placed an instrumental monitor 120m from the larger stained-glass manufacturer in October, 2015. The monthly average atmospheric cadmium concentration was 29.4ng/m(3), which is 49 times higher than Oregon's benchmark of 0.6ng/m(3), and high enough to pose a health risk from even short-term exposure. Both stained-glass manufacturers voluntarily stopped using cadmium after the monitoring results were made public, and the monthly average cadmium levels precipitously dropped to 1.1ng/m(3) for stained-glass manufacturer #1 and 0.67ng/m(3) for stained-glass manufacturer #2.

  18. Using an epiphytic moss to identify previously unknown sources of atmospheric cadmium pollution.

    PubMed

    Donovan, Geoffrey H; Jovan, Sarah E; Gatziolis, Demetrios; Burstyn, Igor; Michael, Yvonne L; Amacher, Michael C; Monleon, Vicente J

    2016-07-15

    Urban networks of air-quality monitors are often too widely spaced to identify sources of air pollutants, especially if they do not disperse far from emission sources. The objectives of this study were to test the use of moss bio-indicators to develop a fine-scale map of atmospherically-derived cadmium and to identify the sources of cadmium in a complex urban setting. We collected 346 samples of the moss Orthotrichum lyellii from deciduous trees in December, 2013 using a modified randomized grid-based sampling strategy across Portland, Oregon. We estimated a spatial linear model of moss cadmium levels and predicted cadmium on a 50m grid across the city. Cadmium levels in moss were positively correlated with proximity to two stained-glass manufacturers, proximity to the Oregon-Washington border, and percent industrial land in a 500m buffer, and negatively correlated with percent residential land in a 500m buffer. The maps showed very high concentrations of cadmium around the two stained-glass manufacturers, neither of which were known to environmental regulators as cadmium emitters. In addition, in response to our findings, the Oregon Department of Environmental Quality placed an instrumental monitor 120m from the larger stained-glass manufacturer in October, 2015. The monthly average atmospheric cadmium concentration was 29.4ng/m(3), which is 49 times higher than Oregon's benchmark of 0.6ng/m(3), and high enough to pose a health risk from even short-term exposure. Both stained-glass manufacturers voluntarily stopped using cadmium after the monitoring results were made public, and the monthly average cadmium levels precipitously dropped to 1.1ng/m(3) for stained-glass manufacturer #1 and 0.67ng/m(3) for stained-glass manufacturer #2. PMID:27058127

  19. Detecting Industrial Pollution in the Atmospheres of Earth-like Exoplanets

    NASA Astrophysics Data System (ADS)

    Lin, Henry W.; Gonzalez Abad, Gonzalo; Loeb, Abraham

    2014-09-01

    Detecting biosignatures, such as molecular oxygen in combination with a reducing gas, in the atmospheres of transiting exoplanets has been a major focus in the search for alien life. We point out that in addition to these generic indicators, anthropogenic pollution could be used as a novel biosignature for intelligent life. To this end, we identify pollutants in the Earth's atmosphere that have significant absorption features in the spectral range covered by the James Webb Space Telescope. We focus on tetrafluoromethane (CF4) and trichlorofluoromethane (CCl3F), which are the easiest to detect chlorofluorocarbons (CFCs) produced by anthropogenic activity. We estimate that ~1.2 days (~1.7 days) of total integration time will be sufficient to detect or constrain the concentration of CCl3F (CF4) to ~10 times the current terrestrial level.

  20. DETECTING INDUSTRIAL POLLUTION IN THE ATMOSPHERES OF EARTH-LIKE EXOPLANETS

    SciTech Connect

    Lin, Henry W.; Abad, Gonzalo Gonzalez; Loeb, Abraham E-mail: ggonzalezabad@cfa.harvard.edu

    2014-09-01

    Detecting biosignatures, such as molecular oxygen in combination with a reducing gas, in the atmospheres of transiting exoplanets has been a major focus in the search for alien life. We point out that in addition to these generic indicators, anthropogenic pollution could be used as a novel biosignature for intelligent life. To this end, we identify pollutants in the Earth's atmosphere that have significant absorption features in the spectral range covered by the James Webb Space Telescope. We focus on tetrafluoromethane (CF{sub 4}) and trichlorofluoromethane (CCl{sub 3}F), which are the easiest to detect chlorofluorocarbons (CFCs) produced by anthropogenic activity. We estimate that ∼1.2 days (∼1.7 days) of total integration time will be sufficient to detect or constrain the concentration of CCl{sub 3}F (CF{sub 4}) to ∼10 times the current terrestrial level.

  1. Bronchitis in two integrated steel works: III. Respiratory symptoms and ventilatory capacity related to atmospheric pollution

    PubMed Central

    Lowe, C. R.; Campbell, H.; Khosla, T.

    1970-01-01

    Lowe, C. R., Campbell, H., and Khosla, T.(1970).Brit. J. industr. Med.,27, 121-129. Bronchitis in two integrated steel works. III. Respiratory symptoms and ventilatory capacity related to atmospheric pollution. This is the third in a series of papers presenting the results of an epidemiological study of respiratory symptomatology and lung function among men employed in two integrated steel works in South Wales. In this paper measurements of atmospheric pollution are related to respiratory symptoms and ventilatory capacity among 10 449 men who spent the greater part of their working hours in one or other of 114 defined working areas. The problem has been explored in three different ways. In the first, each man was assigned the mean value of sulphur dioxide and respirable dust for the area in which he was working and this was related to his ventilatory capacity (FEV1·0), age, smoking habits, and the number of years he had spent in his present department. In the second, the 114 working areas were divided into four sub-groups, according to defined levels of atmospheric pollution, and the prevalence of chronic bronchitis and mean FEV1·0 in the four sub-groups was examined. In the third way, the mean atmospheric pollution levels in each of the 114 areas were related to the prevalence of bronchitis and to the mean FEV1·0, age, and smoking habits in those areas. The analysis demonstrates very clearly the over-riding importance of cigarette smoking in the aetiology of chronic bronchitis, but, so far as the main purpose of the survey is concerned, it is concluded that, if there is any relation between respiratory disability and atmospheric pollution in the two steel works, it is so slight that none of the three approaches to the problem was sensitive enough to detect it. The implications of this are discussed in the light of the levels of pollution that were recorded in and around the two works. PMID:5428631

  2. Characterisation of gaseous and particulate atmospheric pollutants in the East Mediterranean by diffusion denuder sampling lines.

    PubMed

    Perrino, C; Catrambone, M; Esposito, G; Lahav, D; Mamane, Y

    2009-05-01

    A field study aimed to characterize atmospheric pollutants in the gaseous and the particulate phases was conducted during the fall-winter of 2004 and the summer of 2005 in the Ashdod area, Israel. The site is influenced by both anthropogenic sources (power plants, refineries, chemical and metal industries, a cargo port, road traffic) and natural sources (sea-spray and desert dust). The use of diffusion lines--a series of annular diffusion denuders for sampling gaseous compounds followed by a cyclone and a filter pack for determining PM(2.5) composition--allowed a good daily characterization of the main inorganic compounds in both the gaseous (HCl, HNO(3), SO(2), NH(3)) and the particulate phase (Cl(-), NO(3)(-), SO(4)(=), NH(4)(+), and base cations). During the summer campaign two other activities were added: an intensive 3-h sampling period and the determination of PM(2.5) bulk composition. The results were interpreted on the basis of meteorological condition, especially the mixing properties of the lower atmosphere as determined by monitoring the natural radioactivity due to Radon progeny, a good proxy of the atmospheric ability to dilute pollutants. Several pollution episodes were identified and the predominance of different sources was highlighted (sea-spray, desert dust, secondary photochemical pollutants). During the summer period a considerable increase of nitric acid and particulate sulphate was observed. Secondary inorganic pollutants (nitrate, sulphate and ammonium) constituted, on the average, 57% of the fine particle fraction, organic compounds 20%, primary anthropogenic compounds 14%, natural components (sea-spray and crustal elements) 9%. The advantages of the diffusion lines in determining gaseous and particulate N- and S- inorganic compounds are discussed. PMID:18535917

  3. Characterisation of gaseous and particulate atmospheric pollutants in the East Mediterranean by diffusion denuder sampling lines.

    PubMed

    Perrino, C; Catrambone, M; Esposito, G; Lahav, D; Mamane, Y

    2009-05-01

    A field study aimed to characterize atmospheric pollutants in the gaseous and the particulate phases was conducted during the fall-winter of 2004 and the summer of 2005 in the Ashdod area, Israel. The site is influenced by both anthropogenic sources (power plants, refineries, chemical and metal industries, a cargo port, road traffic) and natural sources (sea-spray and desert dust). The use of diffusion lines--a series of annular diffusion denuders for sampling gaseous compounds followed by a cyclone and a filter pack for determining PM(2.5) composition--allowed a good daily characterization of the main inorganic compounds in both the gaseous (HCl, HNO(3), SO(2), NH(3)) and the particulate phase (Cl(-), NO(3)(-), SO(4)(=), NH(4)(+), and base cations). During the summer campaign two other activities were added: an intensive 3-h sampling period and the determination of PM(2.5) bulk composition. The results were interpreted on the basis of meteorological condition, especially the mixing properties of the lower atmosphere as determined by monitoring the natural radioactivity due to Radon progeny, a good proxy of the atmospheric ability to dilute pollutants. Several pollution episodes were identified and the predominance of different sources was highlighted (sea-spray, desert dust, secondary photochemical pollutants). During the summer period a considerable increase of nitric acid and particulate sulphate was observed. Secondary inorganic pollutants (nitrate, sulphate and ammonium) constituted, on the average, 57% of the fine particle fraction, organic compounds 20%, primary anthropogenic compounds 14%, natural components (sea-spray and crustal elements) 9%. The advantages of the diffusion lines in determining gaseous and particulate N- and S- inorganic compounds are discussed.

  4. Observable Effects of Atmospheric Pollution on Outpatient and Inpatient Morbidity in Bulgaria

    PubMed Central

    PLATIKANOVA, Magdalena; PENKOVA-RADICHEVA, Mariana

    2016-01-01

    Background: One of Europe’s most well-developed industrial regions is found in the Republic of Bulgaria. The industrialization of the region has a big impact on air pollution. Thermal power plant “Maritza East” (the largest of its kind in southeastern Europe), the army training range, machine manufacturers, household heating and high volume of automobile traffic are all major sources of pollution in the region. Methods: A five year study (2009–2013) followed yearly concentrations of principal atmospheric pollutants such as sulfur dioxide, dust, nitrogen dioxide, lead aerosols and hydrogen sulfide, and the way in which those levels had an effect on morbidity (outpatient and inpatient medical care) in the area. Statistical processing of data has been completed to represent and analyze the collected data in nonparametric and alternative format. Results: Atmospheric pollution affects human health directly through pathological changes in the human organism. The registered outpatient care provided for the period 2009–2013 is highest for diseases of the cardiovascular system (11.85%), the respiratory system (17.34%) and the genitourinary system (9.76%). The registered rate of hospitalization for the same period is for diseases of the digestive system (11.90%), the cardiovascular system (11.85%), respiratory system (10.86%) and the genitourinary system (8.88%). Conclusion: The observed period shows a decrease in average yearly concentrations of the principal atmospheric pollutants in the industrial region (Bulgaria) and reflects a decrease in morbidity based on outpatient care and an increase in morbidity by inpatient care (hospitalization). Our findings should be corroborated in future longitudinal studies. PMID:27252921

  5. AICE Survey of USSR Air Pollution Literature, Volume 14: Technical Papers from the Leningrad International Symposium on the Meteorological Aspects of Atmospheric Pollution, Part 3.

    ERIC Educational Resources Information Center

    Nuttonson, M. Y.

    Fifteen papers were translated: On the removal of impurities from the atmosphere by clouds and precipitation; Some aspects of the adoption of automatic methods of determining atmospheric pollutants; Recording of sulfur dioxide content at the outskirts of a city. Comparison of measurement results for a valley and an elevation; Theoretical and…

  6. AICE Survey of USSR Air Pollution Literature, Volume 13: Technical Papers from the Leningrad International Symposium on the Meteorological Aspects of Atmospheric Pollution, Part 2.

    ERIC Educational Resources Information Center

    Nuttonson, M. Y., Ed.

    Twelve papers were translated from Russian: Automation of Information Processing Involved in Experimental Studies of Atmospheric Diffusion, Micrometeorological Characteristics of Atmospheric Pollution Conditions, Study of theInfluence of Irregularities of the Earth's Surface on the Air Flow Characteristics in a Wind Tunnel, Use of Parameters of…

  7. Optical Remote-sensing Monitoring and Forecasting of Atmospheric Pollution in Huaibei Area, China

    NASA Astrophysics Data System (ADS)

    Li, Su-wen; Xie, Pin-hua; Jiang, En-hua; Zhang, Yong; Dai, Hai-feng

    2012-12-01

    Huaibei is an energy city. Coal as the primary energy consumption brings a large number of regional pollution in Huaibei area. Differential optical absorption spectroscopy (DOAS) as optical remote sensing technology has been applied to monitor regional average concentrations and inventory of nitrogen dioxide, sulfur dioxide and ozone. DOAS system was set up and applied to monitor the main air pollutants in Huaibei area. Monitoring data were obtained from 7 to 28 August, 2011. Monitoring results show measurements in controlling pollution are effective, and emissions of pollutants are up to the national standard in Huaibei area. Prediction model was also created to track changing trend of pollutions. These will provide raw data support for effective evaluation of environmental quality in Huaibei area.

  8. 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.

  9. Combined eye-atmosphere visibility model

    NASA Technical Reports Server (NTRS)

    Kaufman, Y. J.

    1981-01-01

    Existing models of the optical characteristics of the eye are combined with a recent model of optical characteristics of the atmosphere given by its modulation transfer function. This combination results in the combined eye-atmosphere performance given by the product of their modulation transfer functions. An application for the calculation of visibility thresholds in the case of a two-halves field is given.

  10. An online educational atmospheric global circulation model

    NASA Astrophysics Data System (ADS)

    Navarro, T.; Schott, C.; Forget, F.

    2015-10-01

    As part of online courses on exoplanets of Observatoire de Paris, an online tool designed to vizualise outputs of the Laboratoire de Métérologie Dynamique (LMD) Global Circulation Model (GCM) for various atmospheric circulation regimes has been developed. It includes the possibility for students to visualize 1D and 2D plots along with animations of atmospheric quantities such as temperature, winds, surface pressure, mass flux, etc... from a state-of-the-art model.

  11. An assessment model for atmospheric composition

    NASA Technical Reports Server (NTRS)

    Prather, Michael J. (Editor)

    1988-01-01

    Predicting future perturbations to global air quality and climate requires, as a prerequisite, prognostic models for the composition of the Earth's atmosphere. Such assessment models are needed to evaluate the impact on our environment of different social choices that affect emissions of the photochemically and radiatively important trace gases. Our presentation here of a prototype assessment model is intended to encourage public scientific discussions of the necessary components of the model and their interactions, with the recognition that models similar to this will likely be used by the Environmental Protection Agency and other regulatory agencies in order to assess the effect of changes in atmospheric composition on climate over the next century.

  12. Modeling Callisto's Ionosphere: Insight Into Callisto's Atmosphere

    NASA Astrophysics Data System (ADS)

    Hartkorn, O. A.; Saur, J.; Strobel, D. F.

    2015-12-01

    We develop a kinetic model of the ionosphere of Jupiter's moon Callisto within a prescribed neutral atmosphere composed of O2 and CO2. We calculate the electron energy distribution as a function of space by solving the Boltzmann equation and assuming a stationary balance between local sources and sinks of electrons and electron energy. Electron transport within the ionosphere is neglected, whereas we approximate the electron transport out of the ionosphere into the Jovian magnetosphere. Photoionization is believed to be the major electron source within Callisto's atmosphere. Therefore, we calculate the energy dependent photoelectron spectrum as source term of the Boltzmann equation. The resulting Boltzmann equation is solved rigorously delivering electron distribution functions at every point of Callisto's atmosphere. From these distribution functions, we calculate electron densities and electron impact generated UV emissions from Callisto's atmosphere. The calculated electron densities and UV emissions are compared with observations of the Galileo spacecraft [Kliore et al., 2002] and the Hubble Space Telescope [Cunningham et al., 2015]. Based on these comparisons, we test a physically motivated atmosphere model including asymmetries that depend on Callisto's orbital phase, similar to Europa's atmosphere [Plainaki et al., 2013]. As a result, we gain knowledge about Callisto's atmospheric density and its atmospheric asymmetries.

  13. Atmosphere of Mars: Mariner IV Models Compared.

    PubMed

    Fjeldbo, G; Fjeldbo, W C; Eshleman, V R

    1966-09-23

    Three classes of models for the atmosphere of Mars differ in identifying the main ionospheric layer measured by Mariner IV as being analogous to a terrestrial F(2), F(1), or E layer. At an altitude of several hundred kilometers, the relative atmospheric mass densities for these models (in the order named) are approximately 1, 10(2), and 10(4), and the temperatures are roughly 100 degrees , 200 degrees , and 400 degrees K. Theory and observation are in best agreement for an F, s model, for which photodissociation of CO(2), and diffusive separation result in an atomic-oxygen upper atmosphere, with O(+) being the principal ion in the isothermal topside of the ionosphere. The mesopause temperature minimum would be at or below the freezing point of CO(2), and dry ice particles would be expected to form. However, an F(1) model, with molecular ions in a mixed and warmer upper atmosphere, might result if photodissociation and diffusive separation are markedly less than would be expected from analogy with Earth's upper atmosphere. The E model proposed by Chamberlain and McElroy appears very unlikely; it is not compatible with the measured ionization profile unless rather unlikely assumptions are made about the values, and changes with height, of the effective recombination coefficient and the average ion mass. Moreover our theoretical heat-budget computations for the atmospheric region probed by Mariner IV indicate markedly lower temperatures and temperature gradients than were obtained for the E model. PMID:17749730

  14. Atmosphere of Mars: Mariner IV Models Compared.

    PubMed

    Fjeldbo, G; Fjeldbo, W C; Eshleman, V R

    1966-09-23

    Three classes of models for the atmosphere of Mars differ in identifying the main ionospheric layer measured by Mariner IV as being analogous to a terrestrial F(2), F(1), or E layer. At an altitude of several hundred kilometers, the relative atmospheric mass densities for these models (in the order named) are approximately 1, 10(2), and 10(4), and the temperatures are roughly 100 degrees , 200 degrees , and 400 degrees K. Theory and observation are in best agreement for an F, s model, for which photodissociation of CO(2), and diffusive separation result in an atomic-oxygen upper atmosphere, with O(+) being the principal ion in the isothermal topside of the ionosphere. The mesopause temperature minimum would be at or below the freezing point of CO(2), and dry ice particles would be expected to form. However, an F(1) model, with molecular ions in a mixed and warmer upper atmosphere, might result if photodissociation and diffusive separation are markedly less than would be expected from analogy with Earth's upper atmosphere. The E model proposed by Chamberlain and McElroy appears very unlikely; it is not compatible with the measured ionization profile unless rather unlikely assumptions are made about the values, and changes with height, of the effective recombination coefficient and the average ion mass. Moreover our theoretical heat-budget computations for the atmospheric region probed by Mariner IV indicate markedly lower temperatures and temperature gradients than were obtained for the E model.

  15. InMAP: a new model for air pollution interventions

    NASA Astrophysics Data System (ADS)

    Tessum, C. W.; Hill, J. D.; Marshall, J. D.

    2015-10-01

    Mechanistic air pollution models are essential tools in air quality management. Widespread use of such models is hindered, however, by the extensive expertise or computational resources needed to run most models. Here, we present InMAP (Intervention Model for Air Pollution), which offers an alternative to comprehensive air quality models for estimating the air pollution health impacts of emission reductions and other potential interventions. InMAP estimates annual-average changes in primary and secondary fine particle (PM2.5) concentrations - the air pollution outcome generally causing the largest monetized health damages - attributable to annual changes in precursor emissions. InMAP leverages pre-processed physical and chemical information from the output of a state-of-the-science chemical transport model (WRF-Chem) within an Eulerian modeling framework, to perform simulations that are several orders of magnitude less computationally intensive than comprehensive model simulations. InMAP uses a variable resolution grid that focuses on human exposures by employing higher spatial resolution in urban areas and lower spatial resolution in rural and remote locations and in the upper atmosphere; and by directly calculating steady-state, annual average concentrations. In comparisons run here, InMAP recreates WRF-Chem predictions of changes in total PM2.5 concentrations with population-weighted mean fractional error (MFE) and bias (MFB) < 10 % and population-weighted R2 ~ 0.99. Among individual PM2.5 species, the best predictive performance is for primary PM2.5 (MFE: 16 %; MFB: 13 %) and the worst predictive performance is for particulate nitrate (MFE: 119 %; MFB: 106 %). Potential uses of InMAP include studying exposure, health, and environmental justice impacts of potential shifts in emissions for annual-average PM2.5. Features planned for future model releases include a larger spatial domain, more temporal information, and the ability to predict ground-level ozone (O3

  16. SIRANERISK: Modelling dispersion of steady and unsteady pollutant releases in the urban canopy

    NASA Astrophysics Data System (ADS)

    Soulhac, L.; Lamaison, G.; Cierco, F.-X.; Ben Salem, N.; Salizzoni, P.; Mejean, P.; Armand, P.; Patryl, L.

    2016-09-01

    SIRANERISK is an operational model for the simulation of the dispersion of unsteady atmospheric releases of pollutant within and above an urban area. SIRANERISK is built on the same principles as the SIRANE model, and couples a street network model for the pollutant transfers within the urban canopy with a Gaussian puff model for the transfers above it. The performance of the model are here analysed by a detailed comparisons with wind-tunnel experiments. These experiments concern the dispersion of steady and unsteady pollutant releases within and above obstacle arrays with varying geometrical configurations, representing different topologies of idealised urban districts. The overall good agreement between numerical and experimental data demonstrates the reliability of SIRANERISK as an operational tool for the assessment of risk analysis and for the management of crises due to the accidental release of harmful airborne pollutants within a built environment.

  17. Chemical uncertainties in modeling hot Jupiters atmospheres

    NASA Astrophysics Data System (ADS)

    Hebrard, Eric; Domagal-Goldman, Shawn

    2015-11-01

    Most predictions and interpretations of observations in beyond our Solar System have occurred through the use of 1D photo-thermo-chemical models. Their predicted atmospheric compositions are highly dependent on model parameters. Chemical reactions are based on empirical parameters that must be known at temperatures ranging from 100 K to above 2500 K and at pressures from millibars to hundreds of bars. Obtained from experiments, calculations and educated-guessed estimations, these parameters are always evaluated with substantial uncertainties. However, although of practical use, few models of exoplanetary atmospheres have considered these underlying chemical uncertainties and their consequences. Recent progress has been made recently that allow us to (1) evaluate the accuracy and precision of 1D models of planetary atmospheres, with quantifiable uncertainties on their predictions for the atmospheric composition and associated spectral features, (2) identify the ‘key parameters’ that contribute the most to the models predictivity and should therefore require further experimental or theoretical analysis, (3) reduce and optimize complex chemical networks for their inclusion in multidimensional atmospheric models.First, a global sampling approach based on low discrepancy sequences has been applied in order to propose error bars on simulations of the atmospheres HD 209458b and HD 189733b, using a detailed kinetic model derived from applied combustion models that was methodically validated over a range of temperatures and pressures typical for these hot Jupiters. A two-parameters temperature-dependent uncertainty factor has been assigned to each considered rate constant. Second, a global sensitivity approach based on high dimensional model representations (HDMR) has been applied in order to identify those reactions which make the largest contributions to the overall uncertainty of the simulated results. The HDMR analysis has been restricted to the most important

  18. THE ATMOSPHERIC MODEL EVALUATION (AMET): METEOROLOGY MODULE

    EPA Science Inventory

    An Atmospheric Model Evaluation Tool (AMET), composed of meteorological and air quality components, is being developed to examine the error and uncertainty in the model simulations. AMET matches observations with the corresponding model-estimated values in space and time, and the...

  19. Plant volatiles in a polluted atmosphere: stress response and signal degradation

    PubMed Central

    Blande, James D.; Holopainen, Jarmo K.; Niinemets, Ülo

    2014-01-01

    Plants emit a plethora of volatile organic compounds, which provide detailed information on the physiological condition of emitters. Volatiles induced by herbivore-feeding are among the best studied plant responses to stress and may constitute an informative message to the surrounding community and function in the process of plant defence. However, under natural conditions, plants are potentially exposed to multiple concurrent stresses, which can have complex effects on the volatile emissions. Atmospheric pollutants are an important facet of the abiotic environment and can impinge on a plant’s volatile-mediated defences in multiple ways at multiple temporal scales. They can exert changes in volatile emissions through oxidative stress, as is the case with ozone pollution. They may also react with volatiles in the atmosphere; such is the case for ozone, nitrogen oxides, hydroxyl radicals and other oxidizing atmospheric species. These reactions result in breakdown products, which may themselves be perceived by community members as informative signals. In this review we demonstrate the complex interplay between stress, emitted signals and modification in signal strength and composition by the atmosphere, collectively determining the responses of the biotic community to elicited signals. PMID:24738697

  20. Atmospheric radiation model for water surfaces

    NASA Technical Reports Server (NTRS)

    Turner, R. E.; Gaskill, D. W.; Lierzer, J. R.

    1982-01-01

    An atmospheric correction model was extended to account for various atmospheric radiation components in remotely sensed data. Components such as the atmospheric path radiance which results from singly scattered sky radiation specularly reflected by the water surface are considered. A component which is referred to as the virtual Sun path radiance, i.e. the singly scattered path radiance which results from the solar radiation which is specularly reflected by the water surface is also considered. These atmospheric radiation components are coded into a computer program for the analysis of multispectral remote sensor data over the Great Lakes of the United States. The user must know certain parameters, such as the visibility or spectral optical thickness of the atmosphere and the geometry of the sensor with respect to the Sun and the target elements under investigation.

  1. New Atmospheric Turbulence Model for Shuttle Applications

    NASA Technical Reports Server (NTRS)

    Justus, C. G.; Campbell, C. W.; Doubleday, M. K.; Johnson, D. L.

    1990-01-01

    An updated NASA atmospheric turbulence model, from 0 to 200 km altitude, which was developed to be more realistic and less conservative when applied to space shuttle reentry engineering simulation studies involving control system fuel expenditures is presented. The prior model used extreme turbulence (3 sigma) for all altitudes, whereas in reality severe turbulence is patchy within quiescent atmospheric zones. The updated turublence model presented is designed to be more realistic. The prior turbulence statistics (sigma and L) were updated and were modeled accordingly.

  2. Low surface pressure models for Titan's atmosphere

    NASA Technical Reports Server (NTRS)

    Caldwell, J.

    1978-01-01

    The inversion model for the atmosphere of Titan is reviewed. The basic features of the model are: a cold surface (80 K), a warm stratosphere (160 K) and a low surface pressure (20 mbar). The model is consistent with all existing thermal infrared spectrophotometry, but it cannot preclude the existence of an opaque, cloud, thick atmosphere. The model excludes other gases than methane as bulk constituents. Radio wavelengths observations, including recent data from the very large array, are discussed. These long wavelength observations may be the only direct means of sampling the surface environment before an entry probe or flyby.

  3. A Community Atmosphere Model with Superparameterized Clouds

    SciTech Connect

    Randall, David; Branson, Mark; Wang, Minghuai; Ghan, Steven J.; Craig, Cheryl; Gettelman, A.; Edwards, Jim

    2013-06-18

    In 1999, National Center for Atmospheric Research (NCAR) scientists Wojciech Grabowski and Piotr Smolarkiewicz created a "multiscale" atmospheric model in which the physical processes associated with clouds were represented by running a simple high-resolution model within each grid column of a lowresolution global model. In idealized experiments, they found that the multiscale model produced promising simulations of organized tropical convection, which other models had struggled to produce. Inspired by their results, Colorado State University (CSU) scientists Marat Khairoutdinov and David Randall created a multiscale version of the Community Atmosphere Model (CAM). They removed the cloud parameterizations of the CAM, and replaced them with Khairoutdinov's high-resolution cloud model. They dubbed the embedded cloud model a "super-parameterization," and the modified CAM is now called the "SP-CAM." Over the next several years, many scientists, from many institutions, have explored the ability of the SP-CAM to simulate tropical weather systems, the day-night changes of precipitation, the Asian and African monsoons, and a number of other climate processes. Cristiana Stan of the Center for Ocean-Land-Atmosphere Interactions found that the SP-CAM gives improved results when coupled to an ocean model, and follow-on studies have explored the SP-CAM's utility when used as the atmospheric component of the Community Earth System Model. Much of this research has been performed under the auspices of the Center for Multiscale Modeling of Atmospheric Processes, a National Science Foundation (NSF) Science and Technology Center for which the lead institution is CSU.

  4. Infrared radiation models for atmospheric methane

    NASA Technical Reports Server (NTRS)

    Cess, R. D.; Kratz, D. P.; Caldwell, J.; Kim, S. J.

    1986-01-01

    Mutually consistent line-by-line, narrow-band and broad-band infrared radiation models are presented for methane, a potentially important anthropogenic trace gas within the atmosphere. Comparisons of the modeled band absorptances with existing laboratory data produce the best agreement when, within the band models, spurious band intensities are used which are consistent with the respective laboratory data sets, but which are not consistent with current knowledge concerning the intensity of the infrared fundamental band of methane. This emphasizes the need for improved laboratory band absorptance measurements. Since, when applied to atmospheric radiation calculations, the line-by-line model does not require the use of scaling approximations, the mutual consistency of the band models provides a means of appraising the accuracy of scaling procedures. It is shown that Curtis-Godson narrow-band and Chan-Tien broad-band scaling provide accurate means of accounting for atmospheric temperature and pressure variations.

  5. Modeling of the Coastal Boundary Layer and Pollutant Transport in New England

    NASA Astrophysics Data System (ADS)

    Angevine, Wayne M.; Tjernström, Michael; Žagar, Mark

    2006-01-01

    Concentrations of ozone exceeding regulatory standards are regularly observed along the coasts of New Hampshire and Maine in summer. These events are primarily caused by the transport of pollutants from urban areas in Massachusetts and farther south and west. Pollutant transport is most efficient over the ocean. The coastline makes transport processes complex because it makes the structure of the atmospheric boundary layer complex. During pollution episodes, the air over land in daytime is warmer than the sea surface, so air transported from land over water becomes statically stable and the formerly well-mixed boundary layer separates into possibly several layers, each transported in a different direction. This study examines several of the atmospheric boundary layer processes involved in pollutant transport. A three-dimensional model [the Coupled Ocean Atmosphere Mesoscale Prediction System (COAMPS)] run on grids of 2.5 and 7.5 km is used to examine the winds, thermodynamic structure, and structure of tracer plumes emitted from Boston, Massachusetts, and New York City, New York, in two different real cases—one dominated by large-scale transport (22 23 July 2002) and one with important mesoscale effects (11 14 August 2002). The model simulations are compared with measurements taken during the 2002 New England Air Quality Study. The model simulates the basic structure of the two different episodes well. The boundary layer stability over the cold water is weaker in the model than in reality. The tracer allows for easy visualization of the pollutant transport.

  6. Relationship between Atmospheric Pollution Processes and Atmospheric Circulation in Shanghai, China

    NASA Astrophysics Data System (ADS)

    Ma, Y.; Zhang, J.; Cong, J.; Wang, J.

    2014-12-01

    Severe haze weather occurred in Shanghai in the beginning of 2013. In this paper,spatial-temporal characteristics of the smog days was analyzed using the data of 10 stations in the downtown, the suburb & the outer suburb of Shanghai from 2002-2013. In addition, we discussed the correlation between PM2.5, PM10, SO2 & NO2 and the smog days. At last, the situation of atmospheric circulation during a severe haze weather process between Jan, 2, 2013 to Feb, 4, 2013 was studied. Results show that: (1) from 2002 to 2012, the average smog days in Shanghai and in the outer suburb of Shanghai show a trend of fluctuating decrease generally with the rates of 6.031d/a and 5.89d/a, respectively. The smog days in the downtown of Shanghai decrease most quickly, with the rate of 15.418d/a. The smog days in the suburb of Shanghai decreased most slowly, with the rate of 2.495d/a. Smog happens most frequently in January, November and December (accounting for 31%) and least in August and September. The inter-annual variation of smog days shows the trend of decreasing in all four seasons. The smog days decreases most slowly in spring, with the ratio of 1.16d/a, it decreases most quickly in winter, with the ratio of 1.65d/a, and decreases at the medium ratio of 1.58d/a and 1.49d/a in summer and autumn respectively. (2) The number of monthly average smog days is positively related to the monthly average concentration of PM10, SO2, PM2.5 and NO2. The correlative coefficient between the number of monthly average smog days and the monthly average PM10 and NO2 concentrations are 0.756 and 0.610, respectively. (3) Atmospheric circulation analysis shows that stable west straight current in the air, weak high pressure on the ground and sufficient supplement of water steam are good for the formation and maintenance of haze weather.

  7. CONCENTRATIONS OF TOXIC AIR POLLUTANTS IN THE U.S. SIMULATED BY AN AIR QUALITY MODEL

    EPA Science Inventory

    As part of the US National Air Toxics Assessment, we have applied the Community Multiscale Air Quality Model, CMAQ, to study the concentrations of twenty gas-phase, toxic, hazardous air pollutants (HAPs) in the atmosphere over the continental United States. We modified the Carbo...

  8. Analytical dispersion model for the chain of primary and secondary air pollutants released from point source

    NASA Astrophysics Data System (ADS)

    Juodis, Laurynas; Filistovič, Vitold; Maceika, Evaldas; Remeikis, Vidmantas

    2016-03-01

    An analytical model for dispersion of air pollutants released from a point source forming a secondary pollutant (e.g. chemical transformation or parent-daughter radionuclide chain) is formulated considering the constant wind speed and eddy diffusivities as an explicit function of downwind distance from the source in Cauchy (reflection-deposition type) boundary conditions. The dispersion of pollutants has been investigated by using the Gaussian plume dispersion parameters σy and σz instead of the diffusivity parameters Ky and Kz. For primary pollutant it was proposed to use the derived dry deposition factor instead of the source depletion alternative. An analytical solution for steady-state two-dimensional pollutant transport in the atmosphere is presented. Derived formulas include dependency from effective release height, gravitational and dry deposition velocities of primary and secondary pollutants, advection, surface roughness length and empirical dispersion parameters σy and σz. Demonstration of analytical solution application is provided by calculation of 135Xe and 135C air activity concentrations and the applicability of the model for the solution of atmospheric pollution transport problems.

  9. Impacts of the NAO on atmospheric pollution in the Mediterranean Basin

    NASA Astrophysics Data System (ADS)

    Dayan, U.

    2010-09-01

    The measured concentrations of air pollutants in the lower atmosphere are the result of the combined effect of local-, meso -, and synoptic scale processes. However, there are several inherent problems in attributing pollution concentrations to changes in large-scale atmospheric circulation: 1) the year to year variability being modulated by both, changes in circulation and changes in upwind emissions, 2) the shorter life-time of some pollutants precluding a meaningful relationship with changes in circulation, and 3) the both-ways interaction between trace gases, aerosols and climate. In order to understand the relationship between atmospheric circulation to climatically related variables such as air pollutants, few examples are presented while using Yarnal's (1993) both fundamental approaches: "Circulation to Environment" and "Environment to Circulation". In the first method, an atmospheric circulation classification is performed and then related to an environmental phenomenon. In the second method, the circulation classification is carried over along specific environment-based criteria set for a particular environmental phenomenon. Simulations of transport of anthropogenic CO for high and low phases of the NAO are presented followed by an observational-based study relating the ozone seasonal variability across North Atlantic and the Western Mediterranean to the NAO. Both phases of the NAO controlling dust transport to the Mediterranean are described: the positive phase during summer over the western region and the negative one regulating dust transport over the Eastern Mediterranean in winter. Low NAO indices have been related to a higher cyclonic activity over the western basin. However, Avila and Roda (2002) found no correlation between annual wet deposition of African dust-related elements and the NAO. Their results indicate that, contrary to the Eastern Mediterranean, the two variables (precipitation inversely and dust updraft directly) controlling wet

  10. New atmospheric model of Epsilon Eridani

    NASA Astrophysics Data System (ADS)

    Vieytes, Mariela; Fontenla, Juan; Buccino, Andrea; Mauas, Pablo

    2016-05-01

    We present a new semi-empirical model of the atmosphere of the widely studied K-dwarf Epsilon Eridani (HD 22049). The model is build to reproduce the visible spectral observations from 3800 to 6800 Angstrom and the h and k Mg II lines profiles. The computations were carried out using the Solar-Stellar Radiation Physical Modeling (SSRPM) tools, which calculate non-LTE population for the most important species in the stellar atmosphere. We show a comparison between the synthetic and observed spectrum, obtaining a good agreement in all the studied spectral range.

  11. [Magnetic Response of Dust-loaded Leaves in Parks of Shanghai to Atmospheric Heavy Metal Pollution].

    PubMed

    Liu, Fei; Chu, Hui-min; Zheng, Xiang-min

    2015-12-01

    To reveal the magnetic response to the atmospheric heavy metal pollution in leaves along urban parks, Camphor leaf samples, widely distributed at urban parks, were collected along the year leading wind direction of Shanghai, by setting two vertical and horizontal sections, using rock magnetic properties and heavy metal contents analysis. The results showed that the magnetic minerals of samples were predominated by ferromagnetic minerals, and both the concentration and grain size of magnetite particles gradually decreased with the winter monsoon direction from the main industrial district. A rigorous cleaning of leaves using ultrasonic agitator washer could remove about 63%-90% of low-field susceptibility values of the leaves, and this strongly indicated that the intensity of magnetic signal was mainly controlled by the PMs accumulated on the leaves surfaces. Moreover, there was a significant linear relationship between heavy metals contents (Fe, Mn, Zn, Cu, Cr, V and Pb) and magnetic parameters (0.442 ≤ R ≤ 0.799, P < 0.05), which suggested that magnetic parameters of urban park leaves could be used as a proxy for atmospheric heavy metal pollution. The results of multivariate statistical analysis showed that the content of magnetic minerals and heavy metal indust-loaded tree leaves was affected by associated pollution of industry and traffic. PMID:27011970

  12. [Magnetic Response of Dust-loaded Leaves in Parks of Shanghai to Atmospheric Heavy Metal Pollution].

    PubMed

    Liu, Fei; Chu, Hui-min; Zheng, Xiang-min

    2015-12-01

    To reveal the magnetic response to the atmospheric heavy metal pollution in leaves along urban parks, Camphor leaf samples, widely distributed at urban parks, were collected along the year leading wind direction of Shanghai, by setting two vertical and horizontal sections, using rock magnetic properties and heavy metal contents analysis. The results showed that the magnetic minerals of samples were predominated by ferromagnetic minerals, and both the concentration and grain size of magnetite particles gradually decreased with the winter monsoon direction from the main industrial district. A rigorous cleaning of leaves using ultrasonic agitator washer could remove about 63%-90% of low-field susceptibility values of the leaves, and this strongly indicated that the intensity of magnetic signal was mainly controlled by the PMs accumulated on the leaves surfaces. Moreover, there was a significant linear relationship between heavy metals contents (Fe, Mn, Zn, Cu, Cr, V and Pb) and magnetic parameters (0.442 ≤ R ≤ 0.799, P < 0.05), which suggested that magnetic parameters of urban park leaves could be used as a proxy for atmospheric heavy metal pollution. The results of multivariate statistical analysis showed that the content of magnetic minerals and heavy metal indust-loaded tree leaves was affected by associated pollution of industry and traffic.

  13. Multiple tree-ring isotopes as environmental indicators of diffuse atmospheric pollution in a peri-urban area

    NASA Astrophysics Data System (ADS)

    Doucet, A.; Savard, M. M.; Bégin, C.; Ouarda, T. B.; Marion, J.

    2010-12-01

    The combined analyses of tree-ring δ13C, δ18O, δ15N, 206Pb/207Pb, 206Pb/204Pb and 206Pb/208Pb isotope ratios of three red spruce specimens from the Tantaré ecological reserve located 40 km northwest of Québec City (Canada) were studied with the aim of reconstructing environmental conditions and unravel past air-quality changes of the 1880-2007 period. To separate the tree-ring δ18O and δ13C patterns induced by natural conditions from those generated by anthropogenic perturbations, a linear regression was applied between the most explicative meteorological parameters and the isotopic series for the period of low pollution (1880 to 1909). The model equations were then applied to the most recent part of the series (1910-2007) to verify if climatic conditions have remained the main driver of the tree-ring isotopic variations. The good fit between the modeled and measured δ18O series for the entire studied period suggests that the assimilation of oxygen by red spruce trees is not significantly affected by pollution stress near Québec City. However, the deviation between the measured and modeled δ13C values for the 1944-2007 period indicates that diffuse pollution affected carbon assimilation by the investigated trees. To independently validate if atmospheric pollution could have generated the deviation between the measured and the estimated δ13C values, a linear regression was applied between the portion of the residual δ13C values and atmospheric pollution (Canadian fossil fuel proxy from 1958 to 2000). The nice fit between the modeled δ13C values from the combination of the two regression analyses based on climate and emission proxy strongly supports the hypothesis that there is a natural and an anthropogenic portion in the δ13C variations of the studied specimens. The short-term variations of the red spruce δ15N series are correlated with the instrumentally measured amounts of provincial N emissions for the 1990 to 2006 period (longest measurements

  14. Hydrodynamic models of a Cepheid atmosphere

    NASA Technical Reports Server (NTRS)

    Karp, A. H.

    1975-01-01

    Instead of computing a large number of coarsely zoned hydrodynamic models covering the entire atmospheric instability strip, the author computed a single model as well as computer limitations allow. The implicit hydrodynamic code of Kutter and Sparks was modified to include radiative transfer effects in optically thin zones.

  15. Modeling Atmospheric Energy Deposition (by energetic ions)

    NASA Astrophysics Data System (ADS)

    Parkinson, C. D.; Brain, D. A.; Lillis, R. J.; Liemohn, M. W.; Bougher, S. W.

    2011-12-01

    The structure, dynamics, chemistry, and evolution of planetary upper atmospheres are in large part determined by the available sources of energy. In addition to the solar EUV flux, the solar wind and solar energetic particle (SEP) events are also important sources. Both of these particle populations can significantly affect an atmosphere, causing atmospheric loss and driving chemical reactions. Attention has been paid to these sources from the standpoint of the radiation environment for humans and electronics, but little work has been done to evaluate their impact on planetary atmospheres. At unmagnetized planets or those with crustal field anomalies, in particular, the solar wind and SEPs of all energies have direct access to the atmosphere and so provide a more substantial energy source than at planets having protective global magnetic fields. Additionally, solar wind and energetic particle fluxes should be more significant for planets orbiting more active stars, such as is the case in the early history of the solar system for paleo-Venus and Mars. Therefore quantification of the atmospheric energy input from the solar wind and SEP events is an important component of our understanding of the processes that control their state and evolution. Such modeling has been previously done for Earth, Mars and Jupiter using a guiding center precipitation model with extensive collisional physics. Currently, this code is only valid for particles with small gyroradii in strong uniform magnetic fields. There is a clear necessity for a Lorentz formulation that can perform calculations for cases where there is only a weak or nonexistent magnetic field that includes detailed physical interaction with the atmosphere (i.e. collisional physics). We show initial efforts to apply a full Lorentz motion particle transport model to study the effects of particle precipitation in the upper atmospheres of Venus, Mars, and Titan. A systematic study of the ionization, excitation, and energy

  16. Chemical kinetics and modeling of planetary atmospheres

    NASA Technical Reports Server (NTRS)

    Yung, Yuk L.

    1990-01-01

    A unified overview is presented for chemical kinetics and chemical modeling in planetary atmospheres. The recent major advances in the understanding of the chemistry of the terrestrial atmosphere make the study of planets more interesting and relevant. A deeper understanding suggests that the important chemical cycles have a universal character that connects the different planets and ultimately link together the origin and evolution of the solar system. The completeness (or incompleteness) of the data base for chemical kinetics in planetary atmospheres will always be judged by comparison with that for the terrestrial atmosphere. In the latter case, the chemistry of H, O, N, and Cl species is well understood. S chemistry is poorly understood. In the atmospheres of Jovian planets and Titan, the C-H chemistry of simple species (containing 2 or less C atoms) is fairly well understood. The chemistry of higher hydrocarbons and the C-N, P-N chemistry is much less understood. In the atmosphere of Venus, the dominant chemistry is that of chlorine and sulfur, and very little is known about C1-S coupled chemistry. A new frontier for chemical kinetics both in the Earth and planetary atmospheres is the study of heterogeneous reactions. The formation of the ozone hole on Earth, the ubiquitous photochemical haze on Venus and in the Jovian planets and Titan all testify to the importance of heterogeneous reactions. It remains a challenge to connect the gas phase chemistry to the production of aerosols.

  17. The role of catchment vegetation in reducing atmospheric inputs of pollutant aerosols in Ganga river.

    PubMed

    Shubhashish, Kumar; Pandey, Richa; Pandey, Jitendra

    2012-08-01

    The role of woody perennials in the Ganga river basin in modifying the run-off quality as influenced by atmospheric deposition of pollutant aerosols was investigated. The concentration of seven nutrients and eight metals were measured in atmospheric deposits as well as in run-off water under the influence of five woody perennials. Nutrient retention was recorded maximum for Bougainvillea spectabilis ranged from 4.30 % to 33.70 %. Metal retention was recorded highest for Ficus benghalensis ranged from 5.15 % to 36.98 %. Although some species showed nutrient enrichment, all the species considered in the study invariably contribute to reduce nutrients and metal concentration in run-off water. Reduction in run off was recorded maximum for B. spectabilis (nutrient 6.48 %-40.66 %; metal 7.86 %-22.85 %) and minimum for Ficus religiosa (nutrient 1.68 %-27.19 %; metal 6.55 %-31.55 %). The study forms the first report on the use of woody perennials in reducing input of atmospheric pollutants to Ganga river and has relevance in formulating strategies for river basin management.

  18. Widespread pollution of the South American atmosphere predates the industrial revolution by 240 y.

    PubMed

    Uglietti, Chiara; Gabrielli, Paolo; Cooke, Colin A; Vallelonga, Paul; Thompson, Lonnie G

    2015-02-24

    In the Southern Hemisphere, evidence for preindustrial atmospheric pollution is restricted to a few geological archives of low temporal resolution that record trace element deposition originating from past mining and metallurgical operations in South America. Therefore, the timing and the spatial impact of these activities on the past atmosphere remain poorly constrained. Here we present an annually resolved ice core record (A.D. 793-1989) from the high-altitude drilling site of Quelccaya (Peru) that archives preindustrial and industrial variations in trace elements. During the precolonial period (i.e., pre-A.D. 1532), the deposition of trace elements was mainly dominated by the fallout of aeolian dust and of ash from occasional volcanic eruptions, indicating that metallurgic production during the Inca Empire (A.D. 1438-1532) had a negligible impact on the South American atmosphere. In contrast, a widespread anthropogenic signal is evident after around A.D. 1540, which corresponds with the beginning of colonial mining and metallurgy in Peru and Bolivia, ∼240 y before the Industrial Revolution. This shift was due to a major technological transition for silver extraction in South America (A.D. 1572), from lead-based smelting to mercury amalgamation, which precipitated a massive increase in mining activities. However, deposition of toxic trace metals during the Colonial era was still several factors lower than 20th century pollution that was unprecedented over the entirety of human history.

  19. Widespread pollution of the South American atmosphere predates the industrial revolution by 240 years

    NASA Astrophysics Data System (ADS)

    Uglietti, Chiara; Gabrielli, Paolo; Cooke, Colin; Vallelonga, Paul; Thompson, Lonnie

    2015-04-01

    In the Southern Hemisphere, evidence for preindustrial atmospheric pollution is restricted to a few geological archives of low temporal resolution that record trace element deposition originating from past mining and metallurgical operations in South America. Therefore the timing and the spatial impact of these activities on the past atmosphere remain poorly constrained. Here we present an annually resolved ice-core record (793-1989 AD) from the high altitude drilling site of Quelccaya (Peru) that archives preindustrial and industrial variations in trace elements. During the pre-colonial period (i.e., pre-1532 AD), the deposition of trace elements was mainly dominated by the fallout of aeolian dust and of ash from occasional volcanic eruptions indicating that metallurgic production during the Inca Empire (1438-1532 AD) had a negligible impact on the South American atmosphere. In contrast, a widespread anthropogenic signal is evident after 1540 AD, which corresponds with the beginning of colonial mining and metallurgy in Peru and Bolivia, 240 years prior to the Industrial Revolution. This shift was due to a major technological transition for silver extraction in South America (1572 AD), from lead-based smelting to mercury amalgamation, which precipitated a massive increase in mining activities. However, deposition of toxic trace metals during the Colonial era was still several factors lower than 20th century pollution that was unprecedented over the entirety of human history.

  20. Widespread pollution of the South American atmosphere predates the industrial revolution by 240 y.

    PubMed

    Uglietti, Chiara; Gabrielli, Paolo; Cooke, Colin A; Vallelonga, Paul; Thompson, Lonnie G

    2015-02-24

    In the Southern Hemisphere, evidence for preindustrial atmospheric pollution is restricted to a few geological archives of low temporal resolution that record trace element deposition originating from past mining and metallurgical operations in South America. Therefore, the timing and the spatial impact of these activities on the past atmosphere remain poorly constrained. Here we present an annually resolved ice core record (A.D. 793-1989) from the high-altitude drilling site of Quelccaya (Peru) that archives preindustrial and industrial variations in trace elements. During the precolonial period (i.e., pre-A.D. 1532), the deposition of trace elements was mainly dominated by the fallout of aeolian dust and of ash from occasional volcanic eruptions, indicating that metallurgic production during the Inca Empire (A.D. 1438-1532) had a negligible impact on the South American atmosphere. In contrast, a widespread anthropogenic signal is evident after around A.D. 1540, which corresponds with the beginning of colonial mining and metallurgy in Peru and Bolivia, ∼240 y before the Industrial Revolution. This shift was due to a major technological transition for silver extraction in South America (A.D. 1572), from lead-based smelting to mercury amalgamation, which precipitated a massive increase in mining activities. However, deposition of toxic trace metals during the Colonial era was still several factors lower than 20th century pollution that was unprecedented over the entirety of human history. PMID:25675506

  1. Widespread pollution of the South American atmosphere predates the industrial revolution by 240 y

    PubMed Central

    Uglietti, Chiara; Gabrielli, Paolo; Cooke, Colin A.; Vallelonga, Paul; Thompson, Lonnie G.

    2015-01-01

    In the Southern Hemisphere, evidence for preindustrial atmospheric pollution is restricted to a few geological archives of low temporal resolution that record trace element deposition originating from past mining and metallurgical operations in South America. Therefore, the timing and the spatial impact of these activities on the past atmosphere remain poorly constrained. Here we present an annually resolved ice core record (A.D. 793–1989) from the high-altitude drilling site of Quelccaya (Peru) that archives preindustrial and industrial variations in trace elements. During the precolonial period (i.e., pre-A.D. 1532), the deposition of trace elements was mainly dominated by the fallout of aeolian dust and of ash from occasional volcanic eruptions, indicating that metallurgic production during the Inca Empire (A.D. 1438−1532) had a negligible impact on the South American atmosphere. In contrast, a widespread anthropogenic signal is evident after around A.D. 1540, which corresponds with the beginning of colonial mining and metallurgy in Peru and Bolivia, ∼240 y before the Industrial Revolution. This shift was due to a major technological transition for silver extraction in South America (A.D. 1572), from lead-based smelting to mercury amalgamation, which precipitated a massive increase in mining activities. However, deposition of toxic trace metals during the Colonial era was still several factors lower than 20th century pollution that was unprecedented over the entirety of human history. PMID:25675506

  2. The role of catchment vegetation in reducing atmospheric inputs of pollutant aerosols in Ganga river.

    PubMed

    Shubhashish, Kumar; Pandey, Richa; Pandey, Jitendra

    2012-08-01

    The role of woody perennials in the Ganga river basin in modifying the run-off quality as influenced by atmospheric deposition of pollutant aerosols was investigated. The concentration of seven nutrients and eight metals were measured in atmospheric deposits as well as in run-off water under the influence of five woody perennials. Nutrient retention was recorded maximum for Bougainvillea spectabilis ranged from 4.30 % to 33.70 %. Metal retention was recorded highest for Ficus benghalensis ranged from 5.15 % to 36.98 %. Although some species showed nutrient enrichment, all the species considered in the study invariably contribute to reduce nutrients and metal concentration in run-off water. Reduction in run off was recorded maximum for B. spectabilis (nutrient 6.48 %-40.66 %; metal 7.86 %-22.85 %) and minimum for Ficus religiosa (nutrient 1.68 %-27.19 %; metal 6.55 %-31.55 %). The study forms the first report on the use of woody perennials in reducing input of atmospheric pollutants to Ganga river and has relevance in formulating strategies for river basin management. PMID:22527002

  3. Magnetic Study on Environmental Samples from Guadalajara Mexico for Monitoring of Atmospheric Pollution

    NASA Astrophysics Data System (ADS)

    Aguilar, B.; Cejudo, R.; Bogalo, M. F.; Rosas-Elguera, J.; Quintana, P.; Bautista, F.; Gogichaishvili, A.; Morales, J.

    2013-05-01

    Guadalajara is the second bigger city in Mexico, catalogued as critical zone because of atmospheric pollution levels. The magnetic methodology has been largely used as an alternative way to evaluate the pollution levels as well as identify the critical points in a given area. In this work, results from chemical analyses and magnetic measurements are presented in order to show the correlation between magnetic signal and the pollution level. We analyzed three kinds of environmental samples: urban soils, urban dust and leaves from ficus benjamina. Samples were taken in 30 sites distributed along a main avenue and two secondary avenues, including three points with very poor traffic influence. We determined a ferromagnetic carrier in most of samples, magnetite probably, since the Tc calculated from the thermomagnetic curves is around 580 °C. The magnetic susceptibility (Xlf) as well as the Saturation Isothermal Remanent Magnetization (SIRM) correlate well with the heavy metals content, specially Pb in urban dusts. These results allowed us to identify the most affected points, by vehicular traffic and industrial emissions. Furthermore, the values obtained for these magnetic parameters are above of those found in other studies for polluted cities in Europe and Asia.

  4. Infrared radiation models for atmospheric ozone

    NASA Technical Reports Server (NTRS)

    Kratz, David P.; Ces, Robert D.

    1988-01-01

    A hierarchy of line-by-line, narrow-band, and broadband infrared radiation models are discussed for ozone, a radiatively important atmospheric trace gas. It is shown that the narrow-band (Malkmus) model is in near-precise agreement with the line-by-line model, thus providing a means of testing narrow-band Curtis-Godson scaling, and it is found that this scaling procedure leads to errors in atmospheric fluxes of up to 10 percent. Moreover, this is a direct consequence of the altitude dependence of the ozone mixing ratio. Somewhat greater flux errors arise with use of the broadband model, due to both a lesser accuracy of the broadband scaling procedure and to inherent errors within the broadband model, despite the fact that this model has been tuned to the line-by-line model.

  5. Atmospheric Modeling And Sensor Simulation (AMASS) study

    NASA Technical Reports Server (NTRS)

    Parker, K. G.

    1984-01-01

    The capabilities of the atmospheric modeling and sensor simulation (AMASS) system were studied in order to enhance them. This system is used in processing atmospheric measurements which are utilized in the evaluation of sensor performance, conducting design-concept simulation studies, and also in the modeling of the physical and dynamical nature of atmospheric processes. The study tasks proposed in order to both enhance the AMASS system utilization and to integrate the AMASS system with other existing equipment to facilitate the analysis of data for modeling and image processing are enumerated. The following array processors were evaluated for anticipated effectiveness and/or improvements in throughput by attachment of the device to the P-e: (1) Floating Point Systems AP-120B; (2) Floating Point Systems 5000; (3) CSP, Inc. MAP-400; (4) Analogic AP500; (5) Numerix MARS-432; and (6) Star Technologies, Inc. ST-100.

  6. Remote sensing of atmospheric urban pollutants with DOAS in Castilla-La Mancha (Spain)

    NASA Astrophysics Data System (ADS)

    Saiz, A.; Poblete, F. J.; Mucientes, A. E.; Maigler, F. J.; Notario, A.; Martínez, E.; Albaladejo, J.

    Urban air pollution is one of the main environmental problems, owing to implications for public health and physical environment. In urban areas, the sources of atmospheric pollutants are distributed very inhomogeneously. Trace gas concentrations measured by conventional air quality monitoring stations are always influenced by small sources in their direct vicinity and surface effects like dry deposition and small-scale wind systems. Differential Optical Absorption Spectroscopy (DOAS) is a field-oriented monitoring technique that allows very fast and continuous measurements of different airborne pollutants along an open light path. Remote sensing techniques like DOAS can avoid the problems of local influences and surface effects, as DOAS can use light paths with range from several hundred of meters to several kilometres, thus the measured concentrations are averaged over the light path and barely influenced by small-scale variances. The technique is based on the fact that all trace gases absorb electromagnetic radiation in some part of the spectrum. If the radiation of the appropriate frequency is transmitted through the atmosphere the features of absorption of each molecule in that spectral region allow the identification and quantification of the gas concentrations. Up to date, only a few long term DOAS measurements of urban air pollution have been reported, and to the best of our knowledge, this study is the first one in the South of Spain. We present here some results obtained in a long term study performed in Ciudad Real and Puertollano, where the daily, weekly and seasonal variation of the concentrations of minor important tropospheric constituents as ozone, nitric oxide, nitrogen dioxide and sulphur dioxide, have been continuously monitored.

  7. The horizontal transport of pollutants from a slope wind layer into the valley core as a function of atmospheric stability

    NASA Astrophysics Data System (ADS)

    Leukauf, Daniel; Gohm, Alexander; Rotach, Mathias W.; Posch, Christian

    2016-04-01

    Slope winds provide a mechanism for the vertical exchange of air between the valley and the free atmosphere aloft. By this means, heat, moisture and pollutants are exported or imported. However, it the static stability of the valley atmosphere is strong, one part of the up-slope flow is redirected towards the valley center and pollutants are recirculated within the valley. This may limit the venting potential of slope winds severely. The main objective of this study is to quantify the horizontal transport of pollutants from the slope wind layer into the stable valley core and to determine the dependency of this flux as a function of the initial stability of the atmosphere. For this purpose, we conducted large eddy simulations with the Weather Research and Forecasting (WRF) model for a quasi-two-dimensional valley. The valley geometry consists of two slopes with constant slope angle rising to a crest height of 1500 m and a 4 km wide flat valley floor in between. The valley is 20 km long and homogeneous in along-valley direction. Hence, only slope winds but no valley winds can evolve. The surface sensible heat flux is prescribed by a sine function with an amplitude of 125 W m-2. The initial sounding characterized by an atmosphere at rest and by a constant Brunt-Väisälä frequency which is varied between 0.006 s-1 and 0.02 s-1. A passive tracer is released with an arbitrary but constant rate at the valley floor. As expected, the atmospheric stability has a strong impact on the vertical and horizontal transport of tracer mass. A horizontal intrusion forms at the top of the mixed layer due to outflow from the slope wind layer. Tracer mass is transported from the slope towards the center of the valley. The efficiency of this mechanism increases with increasing stability N. For the lowest value of N, about 70% of the tracer mass released at the valley bottom is exported out of the valley. This value drops to about 12% in the case of the strongest stability. Hence, most

  8. Tagging Water Sources in Atmospheric Models

    NASA Technical Reports Server (NTRS)

    Bosilovich, M.

    2003-01-01

    Tagging of water sources in atmospheric models allows for quantitative diagnostics of how water is transported from its source region to its sink region. In this presentation, we review how this methodology is applied to global atmospheric models. We will present several applications of the methodology. In one example, the regional sources of water for the North American Monsoon system are evaluated by tagging the surface evaporation. In another example, the tagged water is used to quantify the global water cycling rate and residence time. We will also discuss the need for more research and the importance of these diagnostics in water cycle studies.

  9. Characteristics of major secondary ions in typical polluted atmospheric aerosols during autumn in central Taiwan.

    PubMed

    Fang, Guor-Cheng; Lin, Shih-Chieh; Chang, Shih-Yu; Lin, Chuan-Yao; Chou, Charles-C K; Wu, Yun-Jui; Chen, Yu-Chieh; Chen, Wei-Tzu; Wu, Tsai-Lin

    2011-06-01

    In autumn of 2008, the chemical characteristics of major secondary ionic aerosols at a suburban site in central Taiwan were measured during an annually occurring season of high pollution. The semicontinuous measurement system measured major soluble inorganic species, including NH(4)(+), NO(3)(-), and SO(4)(2-), in PM(10) with a 15 min resolution time. The atmospheric conditions, except for the influences of typhoons, were dominated by the local sea-land breeze with clear diurnal variations of meteorological parameters and air pollutant concentrations. To evaluate secondary aerosol formation at different ozone levels, daily ozone maximum concentration (O(3,daily max)) was used as an index of photochemical activity for dividing between the heavily polluted period (O(3,daily max) ≧80 ppb) and the lightly polluted period (O(3,daily max)<80 ppb). The concentrations of PM(10), NO(3)(-), SO(4)(2-), NH(4)(+) and total major ions during the heavily polluted period were 1.6, 1.9, 2.4, 2.7 and 2.3 times the concentrations during the lightly polluted period, respectively. Results showed that the daily maximum concentrations of PM(10) occurred around midnight and the daily maximum ozone concentration occurred during daytime. The average concentration of SO(2) was higher during daytime, which could be explained by the transportation of coastal industry emissions to the sampling site. In contrast, the high concentration of NO(2) at night was due to the land breeze flow that transport inland urban air masses toward this site. The simulations of breeze circulations and transitions were reflected in transports and distributions of these pollutants. During heavily polluted periods, NO(3)(-) and NH(4)(+) showed a clear diurnal variations with lower concentrations after midday, possibly due to the thermal volatilization of NH(4)NO(3) during daytime and transport of inland urban plume at night. The diurnal variation of PM(10) showed the similar pattern to that of NO(3)(-) and NH(4

  10. Coupling approaches used in atmospheric entry models

    NASA Astrophysics Data System (ADS)

    Gritsevich, M. I.

    2012-09-01

    While a planet orbits the Sun, it is subject to impact by smaller objects, ranging from tiny dust particles and space debris to much larger asteroids and comets. Such collisions have taken place frequently over geological time and played an important role in the evolution of planets and the development of life on the Earth. Though the search for near-Earth objects addresses one of the main points of the Asteroid and Comet Hazard, one should not underestimate the useful information to be gleaned from smaller atmospheric encounters, known as meteors or fireballs. Not only do these events help determine the linkages between meteorites and their parent bodies; due to their relative regularity they provide a good statistical basis for analysis. For successful cases with found meteorites, the detailed atmospheric path record is an excellent tool to test and improve existing entry models assuring the robustness of their implementation. There are many more important scientific questions meteoroids help us to answer, among them: Where do these objects come from, what are their origins, physical properties and chemical composition? What are the shapes and bulk densities of the space objects which fully ablate in an atmosphere and do not reach the planetary surface? Which values are directly measured and which are initially assumed as input to various models? How to couple both fragmentation and ablation effects in the model, taking real size distribution of fragments into account? How to specify and speed up the recovery of a recently fallen meteorites, not letting weathering to affect samples too much? How big is the pre-atmospheric projectile to terminal body ratio in terms of their mass/volume? Which exact parameters beside initial mass define this ratio? More generally, how entering object affects Earth's atmosphere and (if applicable) Earth's surface? How to predict these impact consequences based on atmospheric trajectory data? How to describe atmospheric entry

  11. The Due Innovators II Apollo Project: Monitoring Atmospheric Pollution with Earth Observations

    NASA Astrophysics Data System (ADS)

    Sellitto, P.; Del Frate, F.; Di Noia, A.; Sambucini, V.; Bojkov, B. R.

    2010-12-01

    In this paper we present the Innovators II - APOLLO (monitoring Atmospheric POLLution with earth Observation) project which has been carried out in the framework of the ESA Data User Element programme (http://www.esa.int/due). The projects aims at the development of an innovative service for the monitoring of the air quality from ground based measurements and by means of satellite data e.g. provided by the OMI mission. The core of the APOLLO project is the OMI-TOC NN (neural networks) algorithm.

  12. Acid rain and dry deposition of atmospheric pollutants: ORNL studies the effects

    SciTech Connect

    Shriner, D.

    1984-01-01

    Acidic precipitation and atmospheric deposition may be involved in the decline of some forests and in the elevation of aluminum levels in streams. The research programs at Oak Ridge National Laboratory which are focussed on acid rain are described. Some of the areas currently under scrutiny are: soil buffering capacity, the quantitative relationships between wet and dry deposition, the effects of acid rain on forest growth, forest canopy interactions with acid precipitation, the effects of acid rain on aquatic ecosystems, and innovations in pollution control technology.

  13. Vehicular pollution modeling using the operational street pollution model (OSPM) for Chembur, Mumbai (India).

    PubMed

    Kumar, Awkash; Ketzel, Matthias; Patil, Rashmi S; Dikshit, Anil Kumar; Hertel, Ole

    2016-06-01

    Megacities in India such as Mumbai and Delhi are among the most polluted places in the world. In the present study, the widely used operational street pollution model (OSPM) is applied for assessing pollutant loads in the street canyons of Chembur, a suburban area just outside Mumbai city. Chembur is both industrialized and highly congested with vehicles. There are six major street canyons in this area, for which modeling has been carried out for NOx and particulate matter (PM). The vehicle emission factors for Indian cities have been developed by Automotive Research Association of India (ARAI) for PM, not specifically for PM10 or PM2.5. The model has been applied for 4 days of winter season and for the whole year to see the difference of effect of meteorology. The urban background concentrations have been obtained from an air quality monitoring station. Results have been compared with measured concentrations from the routine monitoring performed in Mumbai. NOx emissions originate mainly from vehicles which are ground-level sources and are emitting close to where people live. Therefore, those emissions are highly relevant. The modeled NOx concentration compared satisfactorily with observed data. However, this was not the case for PM, most likely because the emission inventory did not contain emission terms due to resuspended particulate matter. PMID:27178051

  14. Vehicular pollution modeling using the operational street pollution model (OSPM) for Chembur, Mumbai (India).

    PubMed

    Kumar, Awkash; Ketzel, Matthias; Patil, Rashmi S; Dikshit, Anil Kumar; Hertel, Ole

    2016-06-01

    Megacities in India such as Mumbai and Delhi are among the most polluted places in the world. In the present study, the widely used operational street pollution model (OSPM) is applied for assessing pollutant loads in the street canyons of Chembur, a suburban area just outside Mumbai city. Chembur is both industrialized and highly congested with vehicles. There are six major street canyons in this area, for which modeling has been carried out for NOx and particulate matter (PM). The vehicle emission factors for Indian cities have been developed by Automotive Research Association of India (ARAI) for PM, not specifically for PM10 or PM2.5. The model has been applied for 4 days of winter season and for the whole year to see the difference of effect of meteorology. The urban background concentrations have been obtained from an air quality monitoring station. Results have been compared with measured concentrations from the routine monitoring performed in Mumbai. NOx emissions originate mainly from vehicles which are ground-level sources and are emitting close to where people live. Therefore, those emissions are highly relevant. The modeled NOx concentration compared satisfactorily with observed data. However, this was not the case for PM, most likely because the emission inventory did not contain emission terms due to resuspended particulate matter.

  15. Long-range atmospheric transport of persistent organic pollutants to remote lacustrine environments.

    PubMed

    Ruiz-Fernández, Ana Carolina; Ontiveros-Cuadras, Jorge Feliciano; Sericano, José L; Sanchez-Cabeza, Joan-Albert; Liong Wee Kwong, Laval; Dunbar, Robert B; Mucciarone, David A; Pérez-Bernal, Libia Hascibe; Páez-Osuna, Federico

    2014-09-15

    Concentrations, temporal trends and fluxes of persistent organic pollutants (POPs: PAHs, PCBs and PBDEs) were determined in soil and (210)Pb-dated sediment cores from remote lacustrine environments (El Tule and Santa Elena lakes) in rural areas of Central Mexico. In both areas, the concentrations of target analytes in soil and sediment samples were comparable and indicative of slightly contaminated environments. The prevalence of low-molecular-weight PAHs in soils suggested their mainly atmospheric origin, in contrast to the aquatic sediments where runoff contribution was also significant. Increasing contamination trends of PCBs and PBDEs were evident, showing maximum fluxes of 4.8 ± 2.1 and 0.3 ± 0.1 ng cm(-2) a(-1) for PCBs and PBDEs, respectively. The predominance of lower-brominated PBDEs and lower-chlorinated PCBs in soils and sediments indicated that their presence is mostly due to long-range atmospheric transport. PMID:24971459

  16. Air-pollution transport characteristics at Mount Tai during two atmospheric campaigns in spring and summer 2007: A meteorological overview

    NASA Astrophysics Data System (ADS)

    Ding, A.; Wang, T.; Wang, W.

    2009-12-01

    As part of China’s 973 research program on acid rain, two measurement campaigns of trace gases, aerosols and cloud/rain water were conducted at Mt Tai in the spring and summer of 2007. This study presents a meteorological overview for the measurement campaign. Main synoptic processes and air masses transport pathways are identified with the aid of surface meteorological observations, global reanalysis data, and back trajectories analysis. A global 3-D chemical transport model (MOZART) are used to simulate and understand the major large-scale air pollution transport mechanisms associated with different synoptic conditions. High-resolution mesoscale meteorological simulation (using WRF-ARW) and Lagrangian Particle release simulations (with WRF/FELEXPART) are conducted to identify the key processes and mechanisms of mesoscale-scale air pollution transport related to mountain-valley breezes and boundary layer - free troposphere exchange under different synoptic conditions in the most polluted North China Plain. The results show that synoptic processes, especially the mid-latitude cyclones, and PBL dynamics play important roles in shaping the variation of trace gases and aerosols at the site. The summit of Mt. Tai, as a receptor of air masses from the entire North China Plain with an air-mass age of 2-3 days, serves as a perfect platform to study atmospheric photochemistry, gas-particle-cloud interaction, and PBL-free troposphere exchange in North China.

  17. Size and time-resolved roadside enrichment of atmospheric particulate pollutants

    NASA Astrophysics Data System (ADS)

    Amato, F.; Viana, M.; Richard, A.; Furger, M.; Prévôt, A. S. H.; Nava, S.; Lucarelli, F.; Bukowiecki, N.; Alastuey, A.; Reche, C.; Moreno, T.; Pandolfi, M.; Pey, J.; Querol, X.

    2011-03-01

    Size and time-resolved roadside enrichments of atmospheric particulate pollutants in PM10 were detected and quantified in a Mediterranean urban environment (Barcelona, Spain). Simultaneous data from one urban background (UB), one traffic (T) and one heavy traffic (HT) location were analysed, and roadside PM10 enrichments (RE) in a number of elements arising from vehicular emissions were calculated. Tracers of primary traffic emissions (EC, Fe, Ba, Cu, Sb, Cr, Sn) showed the largest REs (>70%). Other traffic tracers (Zr, Cd) showed lower but still consistent REs (25-40%), similar to those obtained for mineral matter resulting from road dust resuspension (Ca, La, Ce, Ti, Ga, Sr, 30-40%). The sum of primary and secondary organic carbon showed a RE of 41%, with contributions of secondary OC (SOC) to total OC ranging from 46% at the HT site, 63% at the T site, and 78% in the UB. Finally, other trace elements (As, Co, Bi) showed unexpected but consistent roadside enrichments (23% up to 69%), suggesting a link to traffic emissions even though the emission process is unclear. Hourly-resolved PM speciation data proved to be a highly resourceful tool to determine the source origin of atmospheric pollutants in urban environments. At the HT site, up to 62% of fine Mn was attributable to industrial plumes, whereas coarse Mn levels were mainly attributed to traffic. Similarly, even though Zn showed on average no roadside enrichment and thus was classified as industrial, the hourly-resolved data proved that at least 15% of coarse Zn may be attributed to road traffic emissions. In addition, our results indicate that secondary nitrate formation occurs within the city-scale, even in the absence of long atmospheric residence times or long-range atmospheric transport processes. Characteristic tracer ratios of road traffic emissions were identified: Cu/Sb = 6.8-8.0, Cu/Sn = 4.7-5.4 and Sn/Sb = 1.5.

  18. Size and time-resolved roadside enrichment of atmospheric particulate pollutants

    NASA Astrophysics Data System (ADS)

    Amato, F.; Viana, M.; Richard, A.; Furger, M.; Prevot, A. S. H.; Nava, S.; Lucarelli, F.; Querol, X.; Alastuey, A.; Reche, C.; Moreno, T.; Pandolfi, M.; Pey, J.

    2011-01-01

    Size and time-resolved roadside enrichments of atmospheric particulate pollutants in PM10 were detected and quantified in a Mediterranean urban environment (Barcelona, Spain). Simultaneous data from one urban background (UB), one traffic (T) and one heavy traffic (HT) location were analysed, and roadside PM10 enrichments (RE) in a number of elements arising from vehicular emissions were calculated. Tracers of primary traffic emissions (EC, Fe, Ba, Cu, Sb, Cr, Sn) showed the largest REs (>70%). Other traffic tracers (Zr, Cd) showed lower but still consistent REs (25-40%), similar to those obtained for mineral matter resulting from road dust resuspension (Ca, La, Ce, Ti, Ga, Sr, 30-40%). The sum of primary and secondary organic carbon showed a RE of 41%, with contributions of secondary OC (SOC) to total OC ranging from 46% at the HT site, 63% at the T site, and 78% in the UB. Finally, other trace elements (As, Co, Bi) showed unexpected but consistent roadside enrichments (23% up to 69%), suggesting a link to traffic emissions even though the emission process is unclear. Hourly-resolved PM speciation data proved to be a highly resourceful tool to determine the source origin of atmospheric pollutants in urban environments. At the HT site, up to 62% of fine Mn was attributable to industrial plumes, whereas coarse Mn levels were mainly attributed to traffic. Similarly, even though Zn showed on average no roadside enrichment and thus was classified as industrial, the hourly-resolved data proved that at least 15% of coarse Zn may be attributed to road traffic emissions. In addition, our results indicate that secondary nitrate formation occurs within the city-scale, even in the absence of long atmospheric residence times or long-range atmospheric transport processes.

  19. Mossbauer study of iron-containing atmospheric aerosol in relation to the air pollution.

    NASA Astrophysics Data System (ADS)

    Kopcewicz, B.; Kopcewicz, M.

    2003-04-01

    Observation and monitoring of the aerosol background in the troposphere is very important for atmospheric physics. It is the first step in studying antropogenic components and their impact on the climate. Iron (both Fe(II) and Fe(III)) plays an important role in the multiphase atmospheric chemistry of S(IV) as a catalyst as well as an oxidant, and a photolytic source of OH radical. In order to assess the extent in which the iron content in the troposphere may change and to which extent that change may be attributed to human activity, it is necessary to have a complete picture of the distribution of iron concentration and its variation. For these purposes the Mössbauer spectroscopy was applied to analyze the iron compounds present in atmospheric aerosol. In this presentation we show results of measurements performed on the atmospheric aerosol collected in Poznan and Lodz (industrial cites in central Poland), Mikolajki (lake district, North-East Poland) and Kasprowy Wierch (mountain observatory, 1985 m a.s.l.). Depending to the sampling period and sampling site the significant changes in the iron concentration and chemical properties of the collected aerosol were observed. As a significant part of air pollution, especially in winter months, iron appeared in the form of iron sulfides, which were products of coal combustion. Also, iron oxyhydroxides and iron oxides, mostly hematite (bulk) and in the form of ultra fine particles in superparamagnetic state were observed. Results obtained from Mössbauer measurements were discussed in relation to the concentration of general air pollution.

  20. Coupled land surface/hydrologic/atmospheric models

    NASA Technical Reports Server (NTRS)

    Pielke, Roger; Steyaert, Lou; Arritt, Ray; Lahtakia, Mercedes; Smith, Chris; Ziegler, Conrad; Soong, Su Tzai; Avissar, Roni; Wetzel, Peter; Sellers, Piers

    1993-01-01

    The topics covered include the following: prototype land cover characteristics data base for the conterminous United States; surface evapotranspiration effects on cumulus convection and implications for mesoscale models; the use of complex treatment of surface hydrology and thermodynamics within a mesoscale model and some related issues; initialization of soil-water content for regional-scale atmospheric prediction models; impact of surface properties on dryline and MCS evolution; a numerical simulation of heavy precipitation over the complex topography of California; representing mesoscale fluxes induced by landscape discontinuities in global climate models; emphasizing the role of subgrid-scale heterogeneity in surface-air interaction; and problems with modeling and measuring biosphere-atmosphere exchanges of energy, water, and carbon on large scales.

  1. The effect of nitrogen additions on oak foliage and herbivore communities at sites with high and low atmospheric pollution.

    PubMed

    Eatough Jones, Michele; Paine, Timothy D; Fenn, Mark E

    2008-02-01

    To evaluate plant and herbivore responses to nitrogen we conducted a fertilization study at a low and high pollution site in the mixed conifer forests surrounding Los Angeles, California. Contrary to expectations, discriminant function analysis of oak herbivore communities showed significant response to N fertilization when atmospheric deposition was high, but not when atmospheric deposition was low. We hypothesize that longer-term fertilization treatments are needed at the low pollution site before foliar N nutrition increases sufficiently to affect herbivore communities. At the high pollution site, fertilization was also associated with increased catkin production and higher densities of a byturid beetle that feeds on the catkins of oak. Leaf nitrogen and nitrate were significantly higher at the high pollution site compared to the low pollution site. Foliar nitrate concentrations were positively correlated with abundance of sucking insects, leafrollers and plutellids in all three years of the study.

  2. X-ray irradiated model stellar atmospheres

    NASA Astrophysics Data System (ADS)

    Madej, J.; Różańska, A.

    2000-04-01

    We present equations and details of the computer code for precise calculation of LTE model atmospheres which are illuminated by an external radiation field. Both radiative and hydrostatic equilibrium, and coherent Thomson electron scattering have been assumed. Radiation field at each frequency and depth level is computed with the method of variable Eddington factors. The code is fully suitable for the study of mutual illumination effects in close binaries. We have subsequently computed few sets of model stellar atmospheres of Teff = 1.8x 104 K, and log g = 4.0 (B3 V type star), consisting of hydrogen and helium in solar proportion, and iron of number abundance NFe / N_H = 3.7 x 10-5. We assume, that the atmosphere is illuminated by isotropic X-rays of diluted thermal spectral distribution with temperature Trad =108 K. In case of iron-rich models external X-rays cause heating of the uppermost layers up to 4 x 106 K. Such a choice of Teff and Trad differing by 4 orders of magnitude is relevant to the supposed conditions on some rings of the accretion disk in active galactic nuclei (AGN), illuminated by an X-ray source. Our code qualitatively reproduces the structure of an atmosphere and its spectrum for wavelengths ranging from infrared to X-rays. Outgoing spectra clearly exhibit all three components: spectrum of B star, external X-ray blackbody spectrum partly backscattered by the model atmosphere, and radiation from the uppermost layers, heated to very high temperatures. The latter shows He I and He II Lyman opacity jumps, and numerous b-f jumps of highly ionized iron, all of them in emission. We demonstrate that in all atmospheres of our paper the external illumination by X-rays reduces the H I Lyman jump. This is in agreement with observations of AGNs spectra.

  3. Development of a global pollution model for CO, CH4, and CH2O

    NASA Technical Reports Server (NTRS)

    Peters, L. K.

    1974-01-01

    The current status of a global pollution model for carbon monoxide, methane, and formaldehyde is described. The physico-chemical action is considered of these three pollutants in the troposphere. This geographic restriction is convenient since the tropopause provides a natural boundary across which little transport occurs. The data on sources and sinks for these pollutants is based on available information and assumptions relative to the major man-made and natural contributions. The distributions and concentrations of methane, formaldehyde, and carbon monoxide in the atmosphere are interrelated by the chemical reactions in which they participate. A chemical kinetic model based on the pseudo-steady state approximation for the intermediate species was developed to account for these reactions. The numerical procedure used to mathematically describe the pollution transport is a mass conservative scheme employing an integral flux approach.

  4. Dust in the Sky: Atmospheric Composition. Modeling of Aerosol Optical Thickness

    NASA Technical Reports Server (NTRS)

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

    2000-01-01

    Aerosol is any small particle of matter that rests suspended in the atmosphere. Natural sources, such as deserts, create some aerosols; consumption of fossil fuels and industrial activity create other aerosols. All the microscopic aerosol particles add up to a large amount of material floating in the atmosphere. You can see the particles in the haze that floats over polluted cities. Beyond this visible effect, aerosols can actually lower temperatures. They do this by blocking, or scattering, a portion of the sun's energy from reaching the surface. Because of this influence, scientists study the physical properties of atmospheric aerosols. Reliable numerical models for atmospheric aerosols play an important role in research.

  5. Modeling the Impact of Arctic Shipping Pollution on Air Quality off the Coast of Northern Norway

    NASA Astrophysics Data System (ADS)

    Thomas, J. L.; Law, K.; Marelle, L.; Raut, J.; Jalkanen, J.; Johansson, L.; Roiger, A.; Schlager, H.; Kim, J.; Reiter, A.; Weinzierl, B.; Rose, M.; Fast, J. D.

    2013-12-01

    As the Arctic is undergoing rapid and potentially irreversible changes, such as the shrinking and thinning of sea-ice cover, the levels of atmospheric pollution are expected to rise dramatically due to the emergence of local pollution sources including shipping. Shipping routes through the Arctic (such as Russia's Northern Sea Route) are already used as an alternative to the traditional global transit shipping routes. In summer 2012, the ACCESS (Arctic Climate Change, Economy, and Society) aircraft campaign focused on studying pollution sources off the coast of northern Norway to quantify emissions from shipping and other anthropogenic pollution sources. To complement these measurements, a regional chemical transport model is used to study the impact of shipping pollution on gas and aerosol concentrations in the region. WRF-Chem (The Weather Research and Forecasting Model with Chemistry, which simulates gas and aerosols simultaneously with meteorology) is run with real time shipping emissions from STEAM (Ship Traffic Emission Assessment Model) for July 2012. The STEAM model calculates gas and aerosol emissions of marine traffic based on the ship type and location provided by the Automatic Identification System (AIS). Use of real time position, speed, and ship specific information allows for development of emissions with very high spatial (1x1 km) and temporal (30 min) resolution, which are used in the regional model runs. STEAM emissions have been specifically generated for shipping off the coast of Norway during the entire ACCESS campaign period. Simulated ship plumes from high-resolution model runs are compared to aircraft measurements. The regional impact of current summertime shipping is also examined. At present, relatively light ship traffic off the coast of northern Norway results in only a small impact of shipping pollution on regional atmospheric chemistry. The impact of increased future shipping on regional atmospheric chemistry is also assessed.

  6. A review of toxicity models for realistic atmospheric applications

    NASA Astrophysics Data System (ADS)

    Gunatilaka, Ajith; Skvortsov, Alex; Gailis, Ralph

    2014-02-01

    There are many applications that need to study human health effects caused by exposure to toxic chemicals. Risk analysis for industrial sites, study of population health impacts of atmospheric pollutants, and operations research for assessing the potential impacts of chemical releases in military contexts are some examples. Because of safety risks and the high cost of field trials involving hazardous chemical releases, computer simulations are widely used for such studies. Modelling of atmospheric transport and dispersion of chemicals released into the atmosphere to determine the toxic chemical concentrations to which individuals will be exposed is one main component of these simulations, and there are well established atmospheric dispersion models for this purpose. Estimating the human health effects caused by the exposure to these predicted toxic chemical concentrations is the other main component. A number of different toxicity models for assessing the health effects of toxic chemical exposure are found in the literature. Because these different models have been developed based on different assumptions about the plume characteristics, chemical properties, and physiological response, there is a need to review and compare these models to understand their applicability. This paper reviews several toxicity models described in the literature. The paper also presents results of applying different toxicity models to simulated concentration time series data. These results show that the use of ensemble mean concentrations, which are what atmospheric dispersion models typically provide, to estimate human health effects of exposure to hazardous chemical releases may underestimate their impact when toxic exponent, n, of the chemical is greater than one; the opposite phenomenon appears to hold when n < 1. The results also show that some toxicity models that disregard biological recovery processes may predict greater toxicity than the explicitly parameterised models. Despite

  7. Emissions, transport, and evolution of atmospheric pollutants from China: An observational study

    NASA Astrophysics Data System (ADS)

    Li, Can

    China's air pollution issue, a byproduct of recent phenomenal economic growth, has received increasing attention in light of its local and large-scale impacts. I investigated the emissions, transport, and evolution of pollutants from China using measurements near some source regions in northern China in 2005. Surface pollution near Beijing in March was overall heavy but changed dramatically, as passing mid-latitude cyclones led to fast transitions between polluted prefrontal and clean postfrontal conditions. Large differences found between measurements and inventories suggest substantial uncertainties in emission estimates. Small, coal-fired boilers are shown unlikely to be the major source of inventory error; experiments measuring traffic emissions are called for. Ground-level aerosols absorb light and are from both wind-blown dust and anthropogenic emissions. Their effects on climate are to be further studied. Pollutants at higher altitudes are more likely to have large-scale impact than pollutants that remain near the surface. The aircraft campaign in April was among the first efforts to measure the vertical distribution of pollutants over inland China. The largest pollutant levels observed in the free troposphere during the campaign were related to dry convective lofting over an industrial region. This differs from earlier experiments over the Pacific, which recognized the warm conveyor belt (WCB) as the main lofting mechanism. Dry convection over the continent may be followed by WCB lifting as the systems move out over the ocean. Their relative roles are yet to be determined. Analyses of meteorological and satellite cloud data reveal the importance of in-cloud processing in oxidizing SO2 transported behind cold fronts. Through integration of satellite sensors, in-situ measurements, trajectory and chemical transport models, I tracked a pollution plume as it traveled away from source region. The decay of SO2 in the plume over three days was quantified

  8. Measuring and modelling pollution for risk analysis.

    PubMed

    Zidek, J V; Le, N D

    1999-01-01

    The great scale and complexity of environmental risk analysis offers major methodological challenges to those engaged in policymaking. In this paper we describe some of those challenges from the perspective gained through our work at the University of British Columbia (UBC). We describe some of our experiences with respect to the difficult problems of formulating environmental standards and developing abatement strategies. A failed but instructive attempt to find support for experiments on a promising method of reducing acid rain will be described. Then we describe an approach to scenario analysis under hypothetical new standards. Even with measurements of ambient environmental conditions in hand the problem of inferring actual human exposures remains. For example, in very hot weather people will tend to stay inside and population levels of exposure to e.g. ozone could be well below those predicted by the ambient measurements. Setting air quality criteria should ideally recognize the discrepancies likely to arise. Computer models that incorporate spatial random pollution fields and predict actual exposures from ambient levels will be described. From there we turn to the statistical issues of measurement and modelling and some of the contributions in these areas by the UBC group and its partners elsewhere. In particular we discuss the problem of measurement error when non-linear regression models are used. We sketch our approach to imputing unmeasured predictors needed in such models, deferring details to references cited below. We describe in general terms how those imputed measurements and their errors can be accommodated within the framework of health impact analysis.

  9. Plant volatile organic compounds (VOCs) in ozone (O3) polluted atmospheres: the ecological effects.

    PubMed

    Pinto, Delia M; Blande, James D; Souza, Silvia R; Nerg, Anne-Marja; Holopainen, Jarmo K

    2010-01-01

    Tropospheric ozone (O3) is an important secondary air pollutant formed as a result of photochemical reactions between primary pollutants, such as nitrogen oxides (NOx), and volatile organic compounds (VOCs). O3 concentrations in the lower atmosphere (troposphere) are predicted to continue increasing as a result of anthropogenic activity, which will impact strongly on wild and cultivated plants. O3 affects photosynthesis and induces the development of visible foliar injuries, which are the result of genetically controlled programmed cell death. It also activates many plant defense responses, including the emission of phytogenic VOCs. Plant emitted VOCs play a role in many eco-physiological functions. Besides protecting the plant from abiotic stresses (high temperatures and oxidative stress) and biotic stressors (competing plants, micro- and macroorganisms), they drive multitrophic interactions between plants, herbivores and their natural enemies e.g., predators and parasitoids as well as interactions between plants (plant-to-plant communication). In addition, VOCs have an important role in atmospheric chemistry. They are O3 precursors, but at the same time are readily oxidized by O3, thus resulting in a series of new compounds that include secondary organic aerosols (SOAs). Here, we review the effects of O3 on plants and their VOC emissions. We also review the state of current knowledge on the effects of ozone on ecological interactions based on VOC signaling, and propose further research directions.

  10. Characteristics of atmospheric visibility and its relationship with air pollution in Korea.

    PubMed

    Lee, Jeong-Young; Jo, Wan-Kuen; Chun, Ho-Hwan

    2014-09-01

    Although analysis of long-term data is necessary to obtain reliable information on characteristics of atmospheric visibility and its relationship with air pollution, it has rarely been performed. Therefore, a long-term evaluation of atmospheric visibility in characteristically different Korean cities, as well as a remote island, during 2001 to 2009, was performed in this study. In general, visibility decreased in the studied areas during the 9-yr study period. In addition, all areas displayed a distinct seasonal trend, with high visibility in the cold season relative to the warm season. Weekday visibility, however, did not significantly differ from weekend visibility. Similarly, the number of days per year for both low (<10 km) and high visibility (>19 km) fluctuated during the study period. Busan (a coastal city) exhibited the highest visibility, with an overall average of 17.6 km, followed by Daegu (a basin city), Ulsan (with concentrated petrochemical industries), Ullungdo (a remote island), and Seoul (the capital of Korea). Visibility was found to be significantly correlated with target air pollutants, except for ozone, for all metropolitan cities, whereas it was significantly correlated only with particulate matter with an aerodynamic diameter <10 μm (PM10) and ozone on the remote island (Ullungdo). Among the metropolitan cities, Seoul exhibited the lowest visibility for both the PM10 standard exceedance and non-exceedance days, followed by Ulsan, Daegu, and Busan. The results of this study can be used to establish effective strategies for improving urban visibility and air quality. PMID:25603237

  11. Good manufacturing practice for modelling air pollution: Quality criteria for computer models to calculate air pollution

    NASA Astrophysics Data System (ADS)

    Dekker, C. M.; Sliggers, C. J.

    To spur on quality assurance for models that calculate air pollution, quality criteria for such models have been formulated. By satisfying these criteria the developers of these models and producers of the software packages in this field can assure and account for the quality of their products. In this way critics and users of such (computer) models can gain a clear understanding of the quality of the model. Quality criteria have been formulated for the development of mathematical models, for their programming—including user-friendliness, and for the after-sales service, which is part of the distribution of such software packages. The criteria have been introduced into national and international frameworks to obtain standardization.

  12. Influence of the characteristics of atmospheric boundary layer on the vertical distribution of air pollutant in China's Yangtze River Delta

    NASA Astrophysics Data System (ADS)

    Wang, Chenggang; Cao, Le

    2016-04-01

    Air pollution occurring in the atmospheric boundary layer is a kind of weather phenomenon which decreases the visibility of the atmosphere and results in poor air quality. Recently, the occurrence of the heavy air pollution events has become more frequent all over Asia, especially in Mid-Eastern China. In December 2015, the most severe air pollution in recorded history of China occurred in the regions of Yangtze River Delta and Beijing-Tianjin-Hebei. More than 10 days of severe air pollution (Air Quality Index, AQI>200) appeared in many large cities of China such as Beijing, Tianjin, Shijiazhuang and Baoding. Thus, the research and the management of the air pollution has attracted most attentions in China. In order to investigate the formation, development and dissipation of the air pollutions in China, a field campaign has been conducted between January 1, 2015 and January 28, 2015 in Yangtze River Delta of China, aiming at a intensive observation of the vertical structure of the air pollutants in the atmospheric boundary layer during the time period with heavy pollution. In this study, the observation data obtained in the field campaign mentioned above is analyzed. The characteristics of the atmospheric boundary layer and the vertical distribution of air pollutants in the city Dongshan located in the center of Lake Taihu are shown and discussed in great detail. It is indicated that the stability of the boundary layer is the strongest during the nighttime and the early morning of Dongshan. Meanwhile, the major air pollutants, PM2.5 and PM10 in the boundary layer, reach their maximum values, 177.1μg m-3 and 285μg m-3 respectively. The convective boundary layer height in the observations ranges from approximately 700m to 1100m. It is found that the major air pollutants tend to be confined in a relatively shallow boundary layer, which represents that the boundary layer height is the dominant factor for controlling the vertical distribution of the air pollutants. In

  13. Limestone surfaces in built-up environment as indicators of atmospheric pollution.

    PubMed

    Vella, A J; Camilleri, A; Tabone Adami, J P

    1996-12-01

    The concentration of sulphate on limestone surfaces of the external walls of churches in Malta is shown to be related to their position and distance from a power station, the main local point source of sulphur dioxide pollution. Limestone powder collected from these surfaces was examined for the presence of particles which, under low-power optical microscopy, appear as shiny black amorphous bodies which were interpreted as soot particles; the abundance of these bodies was expressed as a 'black particle count' (BPC). The degree of sulphation and BPC were shown to be correlated with each other and both appeared to be strongly dependent on the prevailing wind. The BPC contour map indicated an important contribution to the parameter from vehicular traffic. It is suggested that the degree of sulphation and BPC of limestone surfaces from the built environment should function as environmental indicators of the relative air quality with respect to SO2 and soot pollution. This data is possibly more accurately representative of the relative long-term air-quality status of different areas of habitation than that deduced from single or episodic measurements of atmospheric pollutant levels. PMID:24194411

  14. Limestone surfaces in built-up environment as indicators of atmospheric pollution.

    PubMed

    Vella, A J; Camilleri, A; Tabone Adami, J P

    1996-12-01

    The concentration of sulphate on limestone surfaces of the external walls of churches in Malta is shown to be related to their position and distance from a power station, the main local point source of sulphur dioxide pollution. Limestone powder collected from these surfaces was examined for the presence of particles which, under low-power optical microscopy, appear as shiny black amorphous bodies which were interpreted as soot particles; the abundance of these bodies was expressed as a 'black particle count' (BPC). The degree of sulphation and BPC were shown to be correlated with each other and both appeared to be strongly dependent on the prevailing wind. The BPC contour map indicated an important contribution to the parameter from vehicular traffic. It is suggested that the degree of sulphation and BPC of limestone surfaces from the built environment should function as environmental indicators of the relative air quality with respect to SO2 and soot pollution. This data is possibly more accurately representative of the relative long-term air-quality status of different areas of habitation than that deduced from single or episodic measurements of atmospheric pollutant levels.

  15. Searching ingredients polluted by polycyclic aromatic hydrocarbons in feeds due to atmospheric or pyrolytic sources.

    PubMed

    Yebra-Pimentel, Iria; Fernández-González, Ricardo; Martínez Carballo, Elena; Simal-Gándara, Jesús

    2012-12-01

    The primary aim of the proposed work is to propose the potential sources of pollution by polycyclic aromatic hydrocarbons (PAHs) in feeds and ingredients. To reach this propose the development of a simple, fast, quantitative and economic method for determining PAHs using liquid-liquid extraction (LLE), clean-up and detection by liquid chromatography with fluorescence detection (LC-FD) in polluting feeds and ingredients was developed. The overall method quantification limits range from 0.020 to 4.0μg/kg and analyte recoveries are between 70% and 105% with relative standard deviations (RSD) lower than 20%. Molecular patterns of PAHs were used to study their distribution in the selected samples by cluster analysis, separating them in two groups: contaminated by atmospheric or pyrolytic sources. In order to find a relationship between the nutritional composition (protein, fibre, ash and fat content), and the hypothetical toxicity of selected feeds, a partial least squared (PLS) analysis was used, showing that fibre was a major contributor. Moreover, the complete data set of 27 feed samples and 25 feed ingredients x 13 PAH concentrations were analysed by PCA to find out what ingredients were controlling PAH pollution.

  16. Seasonal pollution characteristics of organic compounds in atmospheric fine particles in Beijing.

    PubMed

    He, Ling-Yan; Hu, Min; Huang, Xiao-Feng; Zhang, Yuan-Hang; Tang, Xiao-Yan

    2006-04-15

    Beijing is a rapidly developing city with severe and unique air pollution problems. Organic matter is the most abundant fraction in fine particles in Beijing, occupying 30-50% of the total mass, indicating its key role in air pollution control. However, detailed chemical characterization of particulate organic matter in Beijing has never been reported. In this study, fine particles in the urban atmosphere in Beijing were investigated for its organic components by GC/MS technique. Over 100 individual organic compounds were identified and quantified in 25 PM2.5 samples from the summer, autumn and winter of 2002-2003. Alkanes, fatty acids, dicarboxylic acids, polycyclic aromatic hydrocarbons and some important tracer compounds (hopanes, levoglucosan and steroids) were the major constituents with the sum of their concentrations of 502, 1471 and 1403 ng m(-3) in summer, autumn and winter, respectively. Different organic compounds presented apparently different seasonal characteristics, reflecting their different dominant emission sources, such as coal combustion, biomass burning and cooking emission. The abundance and origin of these organic compounds are discussed to reveal seasonal air pollution characteristics of Beijing.

  17. Potential sensitivity of photosynthesis and isoprene emission to direct radiative effects of atmospheric aerosol pollution

    NASA Astrophysics Data System (ADS)

    Strada, S.; Unger, N.

    2015-09-01

    A global Earth system model is applied to quantify the impacts of direct anthropogenic aerosol effective radiative forcing on gross primary productivity (GPP) and isoprene emission. The impacts of different pollution aerosol sources (all anthropogenic, biomass burning and non-biomass burning) are investigated by performing sensitivity experiments. On the global scale, our results show that land carbon fluxes (GPP and isoprene emission) are not sensitive to pollution aerosols, even under a global decline in surface solar radiation (direct + diffuse) by ~ 9 %. At the regional scale, plant productivity (GPP) and isoprene emission show a robust but opposite sensitivity to pollution aerosols, in regions where complex canopies dominate. In eastern North America and Europe, anthropogenic pollution aerosols (mainly from non-biomass burning sources) enhance GPP by +8-12 % on an annual average, with a stronger increase during the growing season (> 12 %). In the Amazon basin and central Africa, biomass burning aerosols increase GPP by +2-5 % on an annual average, with a peak in the Amazon basin during the dry-fire season (+5-8 %). In Europe and China, anthropogenic pollution aerosols drive a decrease in isoprene emission of -2 to -12 % on the annual average. Anthropogenic aerosols affect land carbon fluxes via different mechanisms and we suggest that the dominant mechanism varies across regions: (1) light scattering dominates in the eastern US; (2) cooling in the Amazon basin; and (3) reduction in direct radiation in Europe and China.

  18. The Whole Atmosphere Community Climate Model

    NASA Astrophysics Data System (ADS)

    Boville, B. A.; Garcia, R. R.; Sassi, F.; Kinnison, D.; Roble, R. G.

    The Whole Atmosphere Community Climate Model (WACCM) is an upward exten- sion of the National Center for Atmospheric Research Community Climate System Model. WACCM simulates the atmosphere from the surface to the lower thermosphere (140 km) and includes both dynamical and chemical components. The salient points of the model formulation will be summarized and several aspects of its performance will be discussed. Comparison with observations indicates that WACCM produces re- alistic temperature and zonal wind distributions. Both the mean state and interannual variability will be summarized. Temperature inversions in the midlatitude mesosphere have been reported by several authors and are also found in WACCM. These inver- sions are formed primarily by planetary wave forcing, but the background state on which they form also requires gravity wave forcing. The response to sea surface temperature (SST) anomalies will be examined by com- paring simulations with observed SSTs for 1950-1998 to a simulation with clima- tological annual cycle of SSTs. The response to ENSO events is found to extend though the winter stratosphere and mesosphere and a signal is also found at the sum- mer mesopause. The experimental framework allows the ENSO signal to be isolated, because no other forcings are included (e.g. solar variability and volcanic eruptions) which complicate the observational record. The temperature and wind variations asso- ciated with ENSO are large enough to generate significant perturbations in the chem- ical composition of the middle atmosphere, which will also be discussed.

  19. Preliminary results of a lidar-dial integrated system for the automatic detection of atmospheric pollutants

    NASA Astrophysics Data System (ADS)

    Gaudio, P.; Gelfusa, M.; Richetta, M.

    2012-11-01

    In the last decades, atmospheric pollution in urban and industrial areas has become a major concern of both developed and developing countries. In this context, surveying relative large areas in an automatic way is an increasing common objective of public health organisations. The Lidar-Dial techniques are widely recognized as a cost-effective approach to monitor large portions of the atmosphere and, for example, they have been successful applied to the early detection of forest fire. The studies and preliminary results reported in this paper concern the development of an integrated Lidar-Dial system able to detect sudden releases in air of harmful and polluting substances. The propose approach consists of continuous monitoring of the area under surveillance with a Lidar type measurement (by means of a low cost system). Once a significant increase in the density of a pollutant is revealed, the Dial technique is used to identify the released chemicals. In this paper, the specifications of the proposed station are discussed. The most stringent requirement is the need for a very compact system with a range of at least 600-700 m. Of course, the optical wavelengths must be in an absolute eye-safe range for humans. A conceptual design of the entire system is described and the most important characteristic of the main elements are provided. In particular the capability of the envisaged laser sources, Nd:YAG and CO2 lasers, to provide the necessary quality of the measurements is carefully assessed. Since the detection of dangerous substances must be performed in an automatic way, the monitoring station will be equipped with an adequate set of control and communication devices for independent autonomous operation. The results of the first preliminary tests illustrate the potential of the chosen approach.

  20. VALMET: a valley air pollution model. Final report. Revision 1

    SciTech Connect

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

    1985-04-01

    An air quality model is described for predicting air pollution concentrations in deep mountain valleys arising from nocturnal down-valley transport and diffusion of an elevated pollutant plume, and the fumigation of the plume on the valley floor and sidewalls after sunrise. Included is a technical description of the model, a discussion of the model's applications, the required model inputs, sample calculations and model outputs, and a full listing of the FORTRAN computer program. 55 refs., 27 figs., 6 tabs.

  1. Relationship of atmospheric pollution characterized by gas (NO2) and particles (PM10) to microbial communities living in bryophytes at three differently polluted sites (rural, urban, and industrial).

    PubMed

    Meyer, Caroline; Gilbert, Daniel; Gaudry, André; Franchi, Marielle; Nguyen, Hung Viet; Fabure, Juliette; Bernard, Nadine

    2010-02-01

    Atmospheric pollution has become a major problem for modern societies owing to its fatal effects on both human health and ecosystems. We studied the relationships of nitrogen dioxide atmospheric pollution and metal trace elements contained in atmospheric particles which were accumulated in bryophytes to microbial communities of bryophytes at three differently polluted sites in France (rural, urban, and industrial) over an 8-month period. The analysis of bryophytes showed an accumulation of Cr and Fe at the rural site; Cr, Fe, Zn, Cu, Al, and Pb at the urban site; and Fe, Cr, Pb, Al, Sr, Cu, and Zn at the industrial site. During this study, the structure of the microbial communities which is characterized by biomasses of microbial groups evolved differently according to the site. Microalgae, bacteria, rotifers, and testate amoebae biomasses were significantly higher in the rural site. Cyanobacteria biomass was significantly higher at the industrial site. Fungal and ciliate biomasses were significantly higher at the urban and industrial sites for the winter period and higher at the rural site for the spring period. The redundancy analysis showed that the physico-chemical variables ([NO(2)], relative humidity, temperature, and site) and the trace elements which were accumulated in bryophytes ([Cu], [Sr], [Pb]) explained 69.3% of the variance in the microbial community data. Moreover, our results suggest that microbial communities are potential biomonitors of atmospheric pollution. Further research is needed to understand the causal relationship underlined by the observed patterns.

  2. [Watershed water environment pollution models and their applications: a review].

    PubMed

    Zhu, Yao; Liang, Zhi-Wei; Li, Wei; Yang, Yi; Yang, Mu-Yi; Mao, Wei; Xu, Han-Li; Wu, Wei-Xiang

    2013-10-01

    Watershed water environment pollution model is the important tool for studying watershed environmental problems. Through the quantitative description of the complicated pollution processes of whole watershed system and its parts, the model can identify the main sources and migration pathways of pollutants, estimate the pollutant loadings, and evaluate their impacts on water environment, providing a basis for watershed planning and management. This paper reviewed the watershed water environment models widely applied at home and abroad, with the focuses on the models of pollutants loading (GWLF and PLOAD), water quality of received water bodies (QUAL2E and WASP), and the watershed models integrated pollutant loadings and water quality (HSPF, SWAT, AGNPS, AnnAGNPS, and SWMM), and introduced the structures, principles, and main characteristics as well as the limitations in practical applications of these models. The other models of water quality (CE-QUAL-W2, EFDC, and AQUATOX) and watershed models (GLEAMS and MIKE SHE) were also briefly introduced. Through the case analysis on the applications of single model and integrated models, the development trend and application prospect of the watershed water environment pollution models were discussed. PMID:24483100

  3. [Watershed water environment pollution models and their applications: a review].

    PubMed

    Zhu, Yao; Liang, Zhi-Wei; Li, Wei; Yang, Yi; Yang, Mu-Yi; Mao, Wei; Xu, Han-Li; Wu, Wei-Xiang

    2013-10-01

    Watershed water environment pollution model is the important tool for studying watershed environmental problems. Through the quantitative description of the complicated pollution processes of whole watershed system and its parts, the model can identify the main sources and migration pathways of pollutants, estimate the pollutant loadings, and evaluate their impacts on water environment, providing a basis for watershed planning and management. This paper reviewed the watershed water environment models widely applied at home and abroad, with the focuses on the models of pollutants loading (GWLF and PLOAD), water quality of received water bodies (QUAL2E and WASP), and the watershed models integrated pollutant loadings and water quality (HSPF, SWAT, AGNPS, AnnAGNPS, and SWMM), and introduced the structures, principles, and main characteristics as well as the limitations in practical applications of these models. The other models of water quality (CE-QUAL-W2, EFDC, and AQUATOX) and watershed models (GLEAMS and MIKE SHE) were also briefly introduced. Through the case analysis on the applications of single model and integrated models, the development trend and application prospect of the watershed water environment pollution models were discussed.

  4. Dynamic model of the Earth's upper atmosphere

    NASA Technical Reports Server (NTRS)

    Slowey, J. W.

    1984-01-01

    An initial modification to the MSF/J70 Thermospheric Model, in which the variations due to sudden geomagnetic disturbances upon the Earth's upper atmospheric density structure were modeled is presented. This dynamic model of the geomagnetic variation included is an improved version of one which SAO developed from the analysis of the ESRO 4 mass spectrometer data that was incorporated in the Jacchia 1977 model. The variation with geomagnetic local time as well as with geomagnetic latitude are included, and also the effects due to disturbance of the temperature profiles in the region of energy deposition.

  5. The importance of accurate atmospheric modeling

    NASA Astrophysics Data System (ADS)

    Payne, Dylan; Schroeder, John; Liang, Pang

    2014-11-01

    This paper will focus on the effect of atmospheric conditions on EO sensor performance using computer models. We have shown the importance of accurately modeling atmospheric effects for predicting the performance of an EO sensor. A simple example will demonstrated how real conditions for several sites in China will significantly impact on image correction, hyperspectral imaging, and remote sensing. The current state-of-the-art model for computing atmospheric transmission and radiance is, MODTRAN® 5, developed by the US Air Force Research Laboratory and Spectral Science, Inc. Research by the US Air Force, Navy and Army resulted in the public release of LOWTRAN 2 in the early 1970's. Subsequent releases of LOWTRAN and MODTRAN® have continued until the present. Please verify that (1) all pages are present, (2) all figures are correct, (3) all fonts and special characters are correct, and (4) all text and figures fit within the red margin lines shown on this review document. Complete formatting information is available at http://SPIE.org/manuscripts Return to the Manage Active Submissions page at http://spie.org/submissions/tasks.aspx and approve or disapprove this submission. Your manuscript will not be published without this approval. Please contact author_help@spie.org with any questions or concerns. The paper will demonstrate the importance of using validated models and local measured meteorological, atmospheric and aerosol conditions to accurately simulate the atmospheric transmission and radiance. Frequently default conditions are used which can produce errors of as much as 75% in these values. This can have significant impact on remote sensing applications.

  6. Atmospheric models for post- giant impact planets

    NASA Astrophysics Data System (ADS)

    Lupu, R.; Zahnle, K. J.; Marley, M. S.; Schaefer, L. K.; Fegley, B.; Morley, C.; Cahoy, K.; Freedman, R. S.; Fortney, J. J.

    2013-12-01

    the reflected and emergent flux. We find that these atmospheres are dominated by H2O and CO2, while the formation of CH4, and NH3 is quenched due to short dynamical timescales. Other important constituents are HF, HCl, NaCl, and SO2. These are apparent in the emerging spectra, and can be indicative that an impact has occurred. Estimates including photochemistry and vertical mixing show that these atmospheres are enhanced in sulfur-bearing species, particularly SO2, one of the most important absorbers. At this stage we do not address cloud formation and aerosol opacity. Estimated luminosities for post-impact planets, although lower than predicted by previous models, show that the hottest post-giant-impact planets will be detectable with the planned 30 m-class telescopes. Finally, we use the models to describe the cooling of a post-impact terrestrial planet and briefly investigate its time evolution, which ends as the planet transitions into a more conventional steam atmosphere runaway greenhouse. This calculation brings a significant improvement over previous runaway greenhouse models, by including additional opacity sources and comprehensive line lists for H2O and CO2. We find that the cooling timescale for post-giant impact Earths ranges between about 10^5 and 10^6 years, where the slower cooling is associated with the planet going through a runaway greenhouse stage.

  7. [Pollution evaluation and health risk assessment of heavy metals from atmospheric deposition in Lanzhou].

    PubMed

    Li, Ping; Xue, Su-Yin; Wang, Sheng-Li; Nan, Zhong-Ren

    2014-03-01

    In order to evaluate the contamination and health risk of heavy metals from atmospheric deposition in Lanzhou, samples of atmospheric deposition were collected from 11 sampling sites respectively and their concentrations of heavy metals were determined. The results showed that the average contents of Cu, Pb, Cd, Cr, Ni, Zn and Mn were 82.22, 130.31, 4.34, 88.73, 40.64, 369.23 and 501.49 mg x kg(-1), respectively. There was great difference among different functional areas for all elements except Mn. According to the results, the enrichment factor score of Mn was close to 1, while the enrichment of Zn, Ni, Cu and Cr was more serious, and Pb and Cd were extremely enriched. The assessment results of geoaccumulation index of potential ecological risk indicated that the pollution of Cd in the atmospheric deposition of Lanzhou should be classified as extreme degree, and that of Cu, Ni, Zn, Pb as between slight and extreme degrees, and Cr as practically uncontaminated. Contaminations of atmospheric dust by heavy metals in October to the next March were more serious than those from April to August. Health risk assessment indicated that the heavy metals in atmospheric deposition were mainly ingested by human bodies through hand-mouth ingestion. The non-cancer risk was higher for children than for adults. The order of non-cancer hazard indexes of heavy metals was Pb > Cr > Cd > Cu > Ni > Zn. The non-cancer hazard indexes and carcinogen risks of heavy metals were both lower than their threshold values, suggesting that they will not harm the health.

  8. [Atmospheric pollution characteristic during fireworks burning time in spring festival in Quanzhou suburb].

    PubMed

    Zhao, Jin-ping; Xu, Ya; Zhang, Fu-wang; Chen, Jin-sheng

    2011-05-01

    Atmospheric pollution characteristics during fireworks burning time in 2009 Spring Festival in Quangzhou suburb were studied. Particulate aerosol has been monitored and collected using real-time monitor and middle-volume sampler during fireworks burning time. The objectives of this study were to identify the contents and distributing characteristics of particles, polycyclic aromatic hydrocarbon (PAHs) and water-soluble ions and to discuss sources of these pollutants. The results showed that PM2.5 and PM10 were increased significantly during fireworks burning time. The highest concentration of particles presented time of 00:57-01:27 on New Year's Eve, which the average concentration of PM2.5 and PM10 were reached 1102.43 microm(-3) and 1610.22 microg x m(-3) in 30 min. The concentration of particle- and gas-PAHs were 54.18 ng x m(-1) and 47.10 ng x m(-3), respectively, during fireworks burning time in New Year's Eve, which were higher than that in the normal day. It can be judged by the diagnostic ratios that the primary source of PAHs in Quanzhou suburb were the combustion of coal, biomass and the exhaust emission from diesel vehicles in this region. Results of water-soluble ions indicated that fireworks burning were the main reason to lead to higher concentration of these ions during Spring Festival. Moreover, pollution gases of NOx and SO2 that were origined from fireworks burning, coal combustion and exhaust emission from motor vehicle were supplied precursors to form secondary pollutants, such as NO3- and SO4(2-).

  9. [Atmospheric asbestos pollution in the urban environment: Rome, Orbassano and a control locality (II)].

    PubMed

    Chiappino, G; Todaro, A; Blanchard, O

    1993-01-01

    To complete our previous study which evaluated by TEM the atmospheric concentrations of asbestos in the urban areas of Milan, Casale Monferrato, Brescia, Ancona, Bologna and Florence, the concentrations measured in Rome, Orbassano and in two mountain test locations, one with serpentine rock (Valle di Susa) and the other with granitic rock (Adamello), are now reported. Compared with the towns in northern Italy, which had already shown decreasing pollution levels from Casale Monferrato to Milan, Brescia, Ancona, Bologna and Florence, the levels measured in Rome were extremely low, about ten times lower than those measured in Florence, which were in turn ten times lower than those measured in Milan. In Orbassano the levels near serpentine quarries were slightly higher than the geologic background values. The geologic background level in Valle di Susa was approximately 1 fibre/litre (> 5 microns) and 2.5 fibres/litre (total fibres); asbestos fibres were totally absent in the mountain area with granitic rock. The clearly decreasing values of pollution starting from the northern cities down to Rome lead to the exclusion of motor vehicle traffic as one of the "primary" sources of fibre dispersion. In fact, traffic becomes significant in producing pollution only in the presence of other dispersion sources since it gives rise to "secondary" pollution consisting of ultra-thin fibres through grinding of coarse fibres dispersed from other sources and sedimented on the ground. The authors attribute the main responsibility in maintaining comparatively high concentrations of asbestos fibres in the urban areas of northern Italy to weathered asbestos-cement coverings which act as "primary" sources.

  10. [Prolonged exposure to atmospheric air pollution and mortality from respiratory causes].

    PubMed

    Eilstein, D

    2009-12-01

    Different designs can be used to analyze the relationships between respiratory mortality and long term exposure to atmospheric pollution: epidemiological studies (cohort, prevalence study) demonstrate the reality of the relationship and toxicological studies explain it. Cohort studies have the advantage of being able to take into account many confounding factors and thus avoid biases (which is not the case with prevalence studies), but require significant human and financial resources. They were first adopted in the US, but are now more often applied in Europe. The results are relatively consistent, as they all show a statistically significant association between an increase in particulate pollution and cardiopulmonary mortality. Mortality from lung cancer is also associated with long term exposition to particles and sometimes to ozone or nitrogen oxides. Cerebrovascular diseases and sudden death of young children have also been associated with particulate pollution. The relationships are more powerful for long term than short term exposure but are also linear and without threshold. In order to explain these effects (today the causality of the relationship is certain) there are many possible factors, particularly regarding particulate exposures: an increase in cardiovascular risk biomarkers (fibrinogen, white blood cells, and platelets), atherosclerosis, chronic inflammation of lung tissues increased by acute exposure, etc. More and more studies address the interaction between gene and environment and even epigenetic phenomena which could be responsible of these effects. Public Health impact could be quantified. The European E&H surveillance program Apheis, for example, estimated that if PM2.5 levels remained below 15 microg/m(3), a 30 year old person could see his life expectancy increased by 1 month to 2 years, depending on the studied city. Finally, mortality is not the only relevant indicator for health effects of air pollution. ISAAC studies address asthma

  11. Change of the dynamics of heavy metals concentration in atmospheric precipitation in chatkal nature reservation of the republic of uzbekistan as anthropogenic index of the atmospheric pollution

    NASA Astrophysics Data System (ADS)

    Smirnova, T.; Tolkacheva, G.

    2003-04-01

    At present the investigation of the chemical composition of precipitation is a very actual task in the monitoring of environmental pollution. It is known that heavy metals can be the indices of the anthropogenic atmospheric pollution. The emissions from the mining enterprises, of non-ferrous metallurgy, of chemical industry, from heat-and-power production plants, from transport vehicles fare the sources of the heavy metals ingress into the atmosphere. Their emissions in atmosphere form fine-disperse aerosol fractions and afterwards they fall down together with precipitation onto the underlying surface. Heavy metals have the property of accumulation in environmental objects, which disturbs its ecological balance. One of the problems of the study of the influence of heavy metals pollution on the environment is their travel with the air masses of different origin on large distance. In this concern it is interesting to study the content of the heavy metals in atmospheric aerosols and precipitation in the background zones. Chatkal nature reservation on the territory of Tashkent province presents such background point. For the estimation of the level of atmospheric pollution by heavy metals and evaluation of the possible impact on the background level of air pollution of Chatkal nature reservation by anthropogenic sources (industrial cities of the capital province of Uzbekistan) the data analysis was carried out by the Administration of Environment Pollution Monitoring (AEPM) of hydrometeorological service of the Republic of Uzbekistan. It is necessary to mention that Chatkal biospheric nature reservation is situated in 100 km from Tashkent (the capital of the Republic of Uzbekistan) and in 60 km from Almalyk (the biggest centre of mining-metallurgical and chemical industry of the republic). The station of the complex background monitoring of atmospheric pollution (SCBM) is situated on the territory of this nature reservation. This area is characterized by a typical

  12. Composition and effects of inhalable size fractions of atmospheric aerosols in the polluted atmosphere: part I. PAHs, PCBs and OCPs and the matrix chemical composition.

    PubMed

    Landlová, Linda; Cupr, Pavel; Franců, Juraj; Klánová, Jana; Lammel, Gerhard

    2014-05-01

    Atmospheric particulate matter (PM) abundance, mass size distribution (MSD) and chemical composition are parameters relevant for human health effects. The MSD and phase state of semivolatile organic pollutants were determined at various polluted sites in addition to the PM composition and MSD. The distribution pattern of pollutants varied from side to side in correspondence to main particle sources and PM composition. Levels of particle-associated polycyclic aromatic hydrocarbons (PAHs) were 1-30 ng m(-3) (corresponding to 15-35 % of the total, i.e., gas and particulate phase concentrations), of polychlorinated biphenyls (PCBs) were 2-11 pg m(-3) (4-26 % of the total) and of DDT compounds were 2-12 pg m(-3) (4-23 % of the total). The PM associated amounts of other organochlorine pesticides were too low for quantification. The organics were preferentially found associated with particles <0.45 μm of aerodynamic equivalent diameter. The mass fractions associated with sub-micrometer particles (PM0.95) were 73-90 %, 34-71 % and 36-81 % for PAHs, PCBs and DDT compounds, respectively. The finest particles fraction had the highest aerosol surface concentration (6.3-29.7)×10(-6) cm(-1) (44-70 % of the surface concentration of all size fractions). The data set was used to test gas-particle partitioning models for semivolatile organics for the first time in terms of the organics' MSD and size-dependent PM composition. The results of this study prove that at the various sites particles with diverse size, matrix composition, amount of contaminants and toxicological effects occur. Legislative regulation based on gravimetric determination of PM mass can clearly be insufficient for assessment.

  13. The Ecological Monitoring Of Atmosphere Pollution In A City With Microwave

    NASA Astrophysics Data System (ADS)

    Shirokov, I. B.; Zemlyanukhina, O. M.; Ivanova, E. V.

    2007-05-01

    The ecological problem is a problem of mutual relation of a society and nature preservation of an environment. The development of industry results in increasing of the atmosphere pollution. This paper presents the measurements of degree of pollution zone on several links with length di each. The amount of links depends on city dimension and on presence of enterprises with emission into atmosphere of harmful substances. It is known, that by the emissions in an atmosphere of harmful substances (CO, CO2 , NO etc) the environment refraction coefficient nAV (average value) is changed. So, the phase progression of microwave kd identifies the properties of an environment, where k - microwave propagation constant. In a paper (I. B. Shirokov, M. V. Ivashina, Amplitude and Phase Progression Measurements on Microwave Line-of- Sight Links, IEEE Conf. Proc. IGARSS'01, Sydney, Australia) it was shown the possibility of phase progression measurement on microwave. In this paper it is suggested to abandon the synchronization of the microwave oscillations by low frequency oscillations and to use the origin microwave oscillations as heterodyne ones with the same initial phase and a frequency shift. The length of measurement link can reach several kilometers, so the phase stability of link in low frequency band was enough for phase measurement on microwave band with high accuracy, because of length of testing link is much less than low frequency wavelength. So, presented method let us measure phase difference, which is proportional to phase progression of microwave on line-of-sight link. Taking into account that phase progression of microwave depends on refraction coefficient of medium n, we have possibility to carry out the ecological monitoring of region, where the testing link is placed. However, the phase measurements are uncertain principally. In a paper it is presented the possibility of elimination of these disadvantages by the changing of the frequency f of microwave

  14. Modelling the soil-atmosphere exchange of POPs: Long-term steady state and diurnal fluctuations

    NASA Astrophysics Data System (ADS)

    Bao, Z.; Beckingham, B.; Maier, U.; Haberer, C.; Grathwohl, P.

    2014-12-01

    Soil-atmosphere exchange is an important transport process influencing environmental fate and transport of many persistent organic pollutants (POPs). This study focuses on modelling the gaseous exchange of a semi-volatile polycyclic aromatic hydrocarbon (phenanthrene) between soil and the atmosphere using the multicomponent reactive transport code MIN3P. MIN3P is typically applied to simulate aqueous and vapor phase subsurface transport and reaction processes. We extended the code to also include an atmospheric boundary layer where eddy diffusion and photodegradation take place. The relevant processes and parameters affecting soil-atmosphere exchange were investigated in several scenarios and at various time scales. We found that phenanthrene is well-mixed in the atmospheric boundary layer under neutral or stable atmospheric conditions due to fast eddy diffusion. Uptake of airborne phenanthrene to soils is limited by the soil properties and initially depends on diffusion in soil gas and sorption to the solids. On the long term seepage water dominates transport into deeper soil layers; biodegradation finally leads to steady-state concentration profiles in the subsurface typically achieved after a few centuries. If concentrations in the atmosphere decrease, e.g. due to environmental legislation, then soils become sources for the POPs for the first two months and function as sinks again for the POPs until new steady state concentrations are reached (after decades to centuries). MIN3P was also used to simulate diurnal soil-atmosphere exchanges of airborne pollutants due to temperature changes and photodegradation, both which cause fluctuations in atmospheric concentrations and therefore affect mass transfer between soil and the atmosphere. The model can further be applied to estimate the environmental fate of other POPs between soil and the atmosphere under different environmental pollution and climate change scenarios.

  15. A new model for investigating the mortality effects of multiple air pollutants in air pollution mortality time-series studies.

    PubMed

    Roberts, Steven

    2006-03-01

    Because the U.S. Environmental Protection Agency regulates air pollutants independently, the majority of time-series studies on air pollution and mortality have focused on estimating the adverse health effects of a single pollutant. However, due to the sometimes high correlation between air pollutants, the results from studies that focus on a single air pollutant can be difficult to interpret. In addition, the high correlation between air pollutants can produce problems of interpretation for the standard method of investigating the adverse health effects due to multiple air pollutants. The standard method involves simultaneously including the multiple air pollutants in a single statistical model. Because of this, the development of new models to concurrently estimate the adverse health effects of multiple air pollutants has recently been identified as an important area of future research. In this article, a new model for disentangling the joint effects of multiple air pollutants in air pollution mortality time-series studies is introduced. This new model uses the time-series data to assign each air pollutant a weight that indicates the pollutant's contribution to the air pollution mixture that affects mortality and to estimate the effect of this air pollution mixture on mortality. This model offers an improvement in statistical estimation precision over the standard method. It also avoids problems of interpretation that can occur if the standard method is used. This new model is then illustrated by applying it to time-series data from two U.S. counties.

  16. Causes of daily cycle variability of atmospheric pollutants in a western Mediterranean urban site (DAURE campaign)

    NASA Astrophysics Data System (ADS)

    Reche, Cristina; Moreno, Teresa; Viana, Mar; Querol, Xavier; Alastuey, Andrés.; Jimenez, Jose L.; Pandolfi, Marco; Amato, Fulvio; Pérez, Noemí; Moreno, Natalia

    2010-05-01

    The 2009 DAURE Aerosol Campaign (23-February-2009 to 27-March-2009 and 1-July to 31-July) (see Presentation: Pandolfi et al., section AS3.2) had the objective of characterising the main sources and chemical processes controlling atmospheric pollution due to particulate matter in the Mediterranean site of Barcelona (Spain). An urban and a rural background site were selected in order to describe both kinds of pollution setting. Several parameters were taken into consideration, including the variability of mass concentration in the coarse and fine fractions, particle number, amount of black carbon and the concentration of gaseous pollutants (SO2, H2S, NO, NO2, CO, O3) present. Comparisons between the chemical composition of ambient atmospheric particles during day versus night were made using twelve-hour PM samples. The data shown here are focused on results obtained for the urban site where two main atmospheric settings were distinguishable in winter, namely Atlantic advection versus local air mass recirculation. During the warmer months Saharan dust intrusions added a third important influence on PM background. The data demonstrate that superimposed upon these background influences on city air quality are important local contributions from road traffic, construction-demolition works and shipping. There is also a major local contribution of secondary aerosols, with elevated number of particles occurring at midday (and especially in summer) when nucleation processes are favoured by photochemistry. Concentrations of SO2 peak at different times to the other gaseous pollutants due to regular daytime onshore south-easterly breezes bringing harbour emissions into the city. Road traffic in Barcelona also has a great impact on air quality, as demonstrated by daily and weekly cycles of gaseous pollutants, black carbon and the finer fraction of PM, with peaks being coincident with traffic rush-hours (8-10h and 20-22h), levels of pollution increasing from Monday to Friday, and

  17. The Growing Network of Arctic Atmospheric Observatories Now Allows for Better Monitoring of Arctic Air Pollution

    NASA Astrophysics Data System (ADS)

    Schnell, R. C.

    2008-12-01

    The NOAA Barrow, Alaska, Atmospheric Baseline Observatory has been in continuous operation for 35 years monitoring a wide range of atmospheric parameters. Clear trends in concentrations of radiatively important trace gases such as carbon dioxide, methane, HFCs and CFCs, and nitrous oxide have been established at Barrow. In addition, measurements of both general background and episodic gas and aerosol events from industrial and forest fire sources in Russia, China, Europe and North America have been observed. Along with atmospheric stations in Alert and Eureka, Canada,and Summit, Greenland, individual air pollution events flowing into and across the Arctic Basin are being tracked in time and space. The large gap in similar monitoring across the Russian Arctic is being addressed by new stations/programs at Tiksi and Cherskiy, Russia that were upgraded in 2007/8. There is special interest in monitoring methane at Tiksi and Cherskiy as there is speculation that permafrost melting in the Arctic will release accelerating amounts of methane further driving greenhouse warming.

  18. A global atmospheric model of meteoric iron

    NASA Astrophysics Data System (ADS)

    Feng, Wuhu; Marsh, Daniel R.; Chipperfield, Martyn P.; Janches, Diego; Höffner, Josef; Yi, Fan; Plane, John M. C.

    2013-08-01

    The first global model of meteoric iron in the atmosphere (WACCM-Fe) has been developed by combining three components: the Whole Atmosphere Community Climate Model (WACCM), a description of the neutral and ion-molecule chemistry of iron in the mesosphere and lower thermosphere (MLT), and a treatment of the injection of meteoric constituents into the atmosphere. The iron chemistry treats seven neutral and four ionized iron containing species with 30 neutral and ion-molecule reactions. The meteoric input function (MIF), which describes the injection of Fe as a function of height, latitude, and day, is precalculated from an astronomical model coupled to a chemical meteoric ablation model (CABMOD). This newly developed WACCM-Fe model has been evaluated against a number of available ground-based lidar observations and performs well in simulating the mesospheric atomic Fe layer. The model reproduces the strong positive correlation of temperature and Fe density around the Fe layer peak and the large anticorrelation around 100 km. The diurnal tide has a significant effect in the middle of the layer, and the model also captures well the observed seasonal variations. However, the model overestimates the peak Fe+concentration compared with the limited rocket-borne mass spectrometer data available, although good agreement on the ion layer underside can be obtained by adjusting the rate coefficients for dissociative recombination of Fe-molecular ions with electrons. Sensitivity experiments with the same chemistry in a 1-D model are used to highlight significant remaining uncertainties in reaction rate coefficients, and to explore the dependence of the total Fe abundance on the MIF and rate of vertical transport.

  19. A Global Atmospheric Model of Meteoric Iron

    NASA Technical Reports Server (NTRS)

    Feng, Wuhu; Marsh, Daniel R.; Chipperfield, Martyn P.; Janches, Diego; Hoffner, Josef; Yi, Fan; Plane, John M. C.

    2013-01-01

    The first global model of meteoric iron in the atmosphere (WACCM-Fe) has been developed by combining three components: the Whole Atmosphere Community Climate Model (WACCM), a description of the neutral and ion-molecule chemistry of iron in the mesosphere and lower thermosphere (MLT), and a treatment of the injection of meteoric constituents into the atmosphere. The iron chemistry treats seven neutral and four ionized iron containing species with 30 neutral and ion-molecule reactions. The meteoric input function (MIF), which describes the injection of Fe as a function of height, latitude, and day, is precalculated from an astronomical model coupled to a chemical meteoric ablation model (CABMOD). This newly developed WACCM-Fe model has been evaluated against a number of available ground-based lidar observations and performs well in simulating the mesospheric atomic Fe layer. The model reproduces the strong positive correlation of temperature and Fe density around the Fe layer peak and the large anticorrelation around 100 km. The diurnal tide has a significant effect in the middle of the layer, and the model also captures well the observed seasonal variations. However, the model overestimates the peak Fe+ concentration compared with the limited rocket-borne mass spectrometer data available, although good agreement on the ion layer underside can be obtained by adjusting the rate coefficients for dissociative recombination of Fe-molecular ions with electrons. Sensitivity experiments with the same chemistry in a 1-D model are used to highlight significant remaining uncertainties in reaction rate coefficients, and to explore the dependence of the total Fe abundance on the MIF and rate of vertical transport.

  20. Modeling Optical Properties of Polluted Dust and its Morphological Effects by T-Matrix Method

    NASA Astrophysics Data System (ADS)

    Xu, G.; Yang, P.; Brooks, S. D.

    2015-12-01

    Dust storms largely contribute to regional or global aerosol loads, influence radiative energy budget, and air quality, and cause atmospheric environmental, public health problems. As dusts are transported long distances, aerosols such as black carbon can pollute the air mass along the transport path. Two mixing processes, externally and semi-externally (sticking) mixing may substantially affect the single-scattering and radiative properties of polluted dust particles compared to the unpolluted counterparts. This study focuses on quantifying the changes in the optical properties of dust aerosols due to black carbon contamination. The dust model we use is an irregular polyhedron, which is in good agreement with the laboratory measurement. The black carbon model is spherules aggregate defined with a cluster-cluster aggregation algorithm. Specifically, we define the degree of pollution in terms of two variables, the adhesion degree of pollutants and their mixing ratios, since both can alter the optical properties of polluted dust in different ways. By applying the Invariant Imbedding T-matrix Method (II-TM), we obtain the scattering phase matrix and other optical properties of dust aerosols with different degrees of contamination. Furthermore, the morphological effects on the optical properties of polluted dust are quantified by considering different fractal dimensions of black carbon as particles age. The overall changes due to different degrees of pollution by black carbon are investigated at various wavelengths.

  1. Unified Ion-chemical Model for the Middle Atmosphere

    NASA Astrophysics Data System (ADS)

    Kamsali, Nagaraja; Kamsali, Nagaraja; Datta, Jayati; Prasad, Bsn

    important. Aerosols/particulates exist through out the middle atmosphere: natural and anthropogenic sources at troposphere, background and volcanic sources at stratosphere and dust/particulates from meteoric ablation at mesosphere. Modeling the spatial and temporal variation troposphere conductivity assumes added signifi- cance in view of pollution-generated aerosols that modulate the pollution free (background) conductivity of the atmosphere. Simplified Ion-aerosol model with the steady background aerosols and enhanced aerosols of volcanic origin have been used to model the electrical conductivity of Stratosphere. Simple gas phase ion-chemical reactions are inadequate to explain several D- region observations and heterogeneous ion-aerosol model is used, where aerosols/dust/particulates from meteoric ablation act as sink for electrons and ions. The model is successful in explaining the phenomenon of low-latitude mesospheric echoes from VHF radar studies. The ion-chemical models for the troposphere, stratosphere and mesosphere so far have been successful in explaining the equilibrium ion/electron densities in addition to predicting the changes in ionizable constituents and temperature fluctuation (e.g. Mid-latitude winter anomalies, solar flare events etc.). The possibility of unifying these ion-chemical models for the entire middle atmosphere is discussed.

  2. An integrated Bayesian model for estimating the long-term health effects of air pollution by fusing modelled and measured pollution data: A case study of nitrogen dioxide concentrations in Scotland.

    PubMed

    Huang, Guowen; Lee, Duncan; Scott, Marian

    2015-01-01

    The long-term health effects of air pollution can be estimated using a spatio-temporal ecological study, where the disease data are counts of hospital admissions from populations in small areal units at yearly intervals. Spatially representative pollution concentrations for each areal unit are typically estimated by applying Kriging to data from a sparse monitoring network, or by computing averages over grid level concentrations from an atmospheric dispersion model. We propose a novel fusion model for estimating spatially aggregated pollution concentrations using both the modelled and monitored data, and relate these concentrations to respiratory disease in a new study in Scotland between 2007 and 2011. PMID:26530824

  3. An integrated Bayesian model for estimating the long-term health effects of air pollution by fusing modelled and measured pollution data: A case study of nitrogen dioxide concentrations in Scotland.

    PubMed

    Huang, Guowen; Lee, Duncan; Scott, Marian

    2015-01-01

    The long-term health effects of air pollution can be estimated using a spatio-temporal ecological study, where the disease data are counts of hospital admissions from populations in small areal units at yearly intervals. Spatially representative pollution concentrations for each areal unit are typically estimated by applying Kriging to data from a sparse monitoring network, or by computing averages over grid level concentrations from an atmospheric dispersion model. We propose a novel fusion model for estimating spatially aggregated pollution concentrations using both the modelled and monitored data, and relate these concentrations to respiratory disease in a new study in Scotland between 2007 and 2011.

  4. The Role of Hydrocarbon and Halocarbon Species In The Polluted Urban Atmosphere of Bristol, England.

    NASA Astrophysics Data System (ADS)

    Rivett, A. C.; Martin, D.; Gray, D. J.; Price, C. S.; Nickless, G.; Simmonds, P. G.; Doherty, S. J. O.; Greally, B.; Shallcross, D. E.

    The urban environment is a complex mixture of chemicals, however, due to the high levels of NOx that are generally present, ozone formation is VOC (volatile organic compound) limited. Therefore, it is of great importance to determine the type of VOC that is present in the urban environment, its concentration and how this varies both spatially and temporally. The results of a field campaign carried out from early spring through to the late sum- mer of 2000, in Bristol, England, are presented. Continuous measurements of over 40 hydrocarbons have been made at an urban background site, located at Bristol Uni- versity, for approximately nine months using a GC-FID system and for a selection of halocarbons for approximately one month using a GC-ECD system. Measurements of a smaller set of hydrocarbons were made simultaneously at a roadside site in the centre of Bristol, as part of the U.K. national monitoring network. In this paper the form of the halocarbon time-series is investigated by comparison with the hydrocarbon time-series, air-mass back trajectories and also local weather condi- tions. The variability of hydrocarbon concentrations within the urban environment are also investigated and reasons for discrepancies are discussed. Using principal com- ponent analysis sources for these hydrocarbons have been apportioned. In addition, ozone levels recorded in Bristol have been compared with hydrocarbon levels and in conjunction with trajectory modelling the role played by certain VOCs in the forma- tion of ozone and radicals such as OH is assessed. A simple approximation of radical fluxes is also presented based on the variations of the measured hydrocarbons and the role of biogenically produced compounds such as isoprene in the urban environment is also considered. This study has investigated both local and remote effects on levels of pollutants in the Bristol conurbation. Like any other town or city, Bristol has its own distinctive atmospheric characteristics. A

  5. The Role of Hydrocarbon and Halocarbon Species in the Polluted Urban Atmosphere of Bristol, England.

    NASA Astrophysics Data System (ADS)

    Rivett, A. C.; Martin, D.; Gray, D. J.; Price, C. S.; Nickless, G.; Simmonds, P. G.; O'Doherty, S. J.; Greally, B.; Shallcross, D. E.

    2001-12-01

    The urban environment is a complex mixture of chemicals, however, due to the high levels of NOx that are generally present, ozone formation is VOC (volatile organic compound) limited. Therefore, it is of great importance to determine the type of VOC that is present in the urban environment, its concentration and how this varies both spatially and temporally. The results of a field campaign carried out from early spring through to the late summer of 2000, in Bristol, England, are presented. Continuous measurements of over 40 hydrocarbons have been made at an urban background site, located at Bristol University, for approximately nine months using a GC-FID system and for a selection of halocarbons for approximately one month using a GC-ECD system. Measurements of a smaller set of hydrocarbons were made simultaneously at a roadside site in the centre of Bristol, as part of the U.K. national monitoring network. In this paper the form of the halocarbon time-series is investigated by comparison with the hydrocarbon time-series, air-mass back trajectories and also local weather conditions. The variability of hydrocarbon concentrations within the urban environment are also investigated and reasons for discrepancies are discussed. Using principal component analysis sources for these hydrocarbons have been apportioned. In addition, ozone levels recorded in Bristol have been compared with hydrocarbon levels and in conjunction with trajectory modelling the role played by certain VOCs in the formation of ozone and radicals such as OH is assessed. A simple approximation of radical fluxes is also presented based on the variations of the measured hydrocarbons and the role of biogenically produced compounds such as isoprene in the urban environment is also considered. This study has investigated both local and remote effects on levels of pollutants in the Bristol conurbation. Like any other town or city, Bristol has its own distinctive atmospheric characteristics. A detailed

  6. Modelling future impacts of air pollution using the multi-scale UK Integrated Assessment Model (UKIAM).

    PubMed

    Oxley, Tim; Dore, Anthony J; ApSimon, Helen; Hall, Jane; Kryza, Maciej

    2013-11-01

    Integrated assessment modelling has evolved to support policy development in relation to air pollutants and greenhouse gases by providing integrated simulation tools able to produce quick and realistic representations of emission scenarios and their environmental impacts without the need to re-run complex atmospheric dispersion models. The UK Integrated Assessment Model (UKIAM) has been developed to investigate strategies for reducing UK emissions by bringing together information on projected UK emissions of SO2, NOx, NH3, PM10 and PM2.5, atmospheric dispersion, criteria for protection of ecosystems, urban air quality and human health, and data on potential abatement measures to reduce emissions, which may subsequently be linked to associated analyses of costs and benefits. We describe the multi-scale model structure ranging from continental to roadside, UK emission sources, atmospheric dispersion of emissions, implementation of abatement measures, integration with European-scale modelling, and environmental impacts. The model generates outputs from a national perspective which are used to evaluate alternative strategies in relation to emissions, deposition patterns, air quality metrics and ecosystem critical load exceedance. We present a selection of scenarios in relation to the 2020 Business-As-Usual projections and identify potential further reductions beyond those currently being planned.

  7. Estimating the influence of different urban canopy cover types on atmospheric particulate matter (PM10) pollution abatement in London UK.

    NASA Astrophysics Data System (ADS)

    Tallis, Matthew; Freer-Smith, Peter; Sinnett, Danielle; Aylott, Matthew; Taylor, Gail

    2010-05-01

    In the urban environment atmospheric pollution by PM10 (particulate matter with a diameter less than 10 x 10-6 m) is a problem that can have adverse effects on human health, particularly increasing rates of respiratory disease. The main contributors to atmospheric PM10 in the urban environment are road traffic, industry and power production. The urban tree canopy is a receptor for removing PM10s from the atmosphere due to the large surface areas generated by leaves and air turbulence created by the structure of the urban forest. In this context urban greening has long been known as a mechanism to contribute towards PM10 removal from the air, furthermore, tree canopy cover has a role in contributing towards a more sustainable urban environment. The work reported here has been carried out within the BRIDGE project (SustainaBle uRban plannIng Decision support accountinG for urban mEtabolism). The aim of this project is to assess the fluxes of energy, water, carbon dioxide and particulates within the urban environment and develope a DSS (Decision Support System) to aid urban planners in sustainable development. A combination of published urban canopy cover data from ground, airborne and satellite based surveys was used. For each of the 33 London boroughs the urban canopy was classified to three groups, urban woodland, street trees and garden trees and each group quantified in terms of ground cover. The total [PM10] for each borough was taken from the LAEI (London Atmospheric Emissions Inventory 2006) and the contribution to reducing [PM10] was assessed for each canopy type. Deposition to the urban canopy was assessed using the UFORE (Urban Forest Effects Model) approach. Deposition to the canopy, boundary layer height and percentage reduction of the [PM10] in the atmosphere was assessed using both hourly meterological data and [PM10] and seasonal data derived from annual models. Results from hourly and annual data were compared with measured values. The model was then

  8. Parallel computing in atmospheric chemistry models

    SciTech Connect

    Rotman, D.

    1996-02-01

    Studies of atmospheric chemistry are of high scientific interest, involve computations that are complex and intense, and require enormous amounts of I/O. Current supercomputer computational capabilities are limiting the studies of stratospheric and tropospheric chemistry and will certainly not be able to handle the upcoming coupled chemistry/climate models. To enable such calculations, the authors have developed a computing framework that allows computations on a wide range of computational platforms, including massively parallel machines. Because of the fast paced changes in this field, the modeling framework and scientific modules have been developed to be highly portable and efficient. Here, the authors present the important features of the framework and focus on the atmospheric chemistry module, named IMPACT, and its capabilities. Applications of IMPACT to aircraft studies will be presented.

  9. Pollutant source identification model for water pollution incidents in small straight rivers based on genetic algorithm

    NASA Astrophysics Data System (ADS)

    Zhang, Shou-ping; Xin, Xiao-kang

    2016-01-01

    Identification of pollutant sources for river pollution incidents is an important and difficult task in the emergency rescue, and an intelligent optimization method can effectively compensate for the weakness of traditional methods. An intelligent model for pollutant source identification has been established using the basic genetic algorithm (BGA) as an optimization search tool and applying an analytic solution formula of one-dimensional unsteady water quality equation to construct the objective function. Experimental tests show that the identification model is effective and efficient: the model can accurately figure out the pollutant amounts or positions no matter single pollution source or multiple sources. Especially when the population size of BGA is set as 10, the computing results are sound agree with analytic results for a single source amount and position identification, the relative errors are no more than 5 %. For cases of multi-point sources and multi-variable, there are some errors in computing results for the reasons that there exist many possible combinations of the pollution sources. But, with the help of previous experience to narrow the search scope, the relative errors of the identification results are less than 5 %, which proves the established source identification model can be used to direct emergency responses.

  10. Atmospheric dispersion modelling over complex terrain at small scale

    NASA Astrophysics Data System (ADS)

    Nosek, S.; Janour, Z.; Kukacka, L.; Jurcakova, K.; Kellnerova, R.; Gulikova, E.

    2014-03-01

    Previous study concerned of qualitative modelling neutrally stratified flow over open-cut coal mine and important surrounding topography at meso-scale (1:9000) revealed an important area for quantitative modelling of atmospheric dispersion at small-scale (1:3300). The selected area includes a necessary part of the coal mine topography with respect to its future expansion and surrounding populated areas. At this small-scale simultaneous measurement of velocity components and concentrations in specified points of vertical and horizontal planes were performed by two-dimensional Laser Doppler Anemometry (LDA) and Fast-Response Flame Ionization Detector (FFID), respectively. The impact of the complex terrain on passive pollutant dispersion with respect to the prevailing wind direction was observed and the prediction of the air quality at populated areas is discussed. The measured data will be used for comparison with another model taking into account the future coal mine transformation. Thus, the impact of coal mine transformation on pollutant dispersion can be observed.

  11. Validation of a two-dimensional pollutant dispersion model in an isolated street canyon

    NASA Astrophysics Data System (ADS)

    Chan, T. L.; Dong, G.; Leung, C. W.; Cheung, C. S.; Hung, W. T.

    A two-dimensional numerical model based on Reynolds-averaged Navier-Stokes equations coupled with a series of standard, Renormalization Group (RNG) and realizable k- ɛ turbulence models was developed to simulate the fluid-flow development and pollutant dispersion within an isolated street canyon using the FLUENT code. In the present study, the validation of the numerical model was evaluated using an extensive experimental database obtained from the atmospheric boundary layer wind tunnel at the Meteorological Institute of Hamburg University, Germany (J. Wind Eng. Ind. Aerodyn. 62 (1996) 37) . Among the studied turbulence models, the RNG k- ɛ turbulence model was found to be the most optimum turbulence model coupled with the two-dimensional street canyon model developed in the present study. Both the calculated and measured dimensionless pollutant concentrations have been shown to be less dependent on the variation of wind speed and source strength conditions for the studied street canyon aspect ratio of the B/ H=1 case. However, the street canyon configuration has significant influence on the pollutant dispersion. The wider street and lower height of the buildings are favorable to pollutant dilution within the street canyon. The fluid-flow development has demonstrated that the rotative vortex or vortices generated within the urban street canyon can transport the pollutants from a line source to the wall surfaces of the buildings.

  12. Atmospheric analysis modeling in support of Seasat

    NASA Technical Reports Server (NTRS)

    Langland, R. A.; Stephens, P. L.

    1978-01-01

    Atmospheric objective analysis models were developed and tested in preparation for assessing the utility of Seasat data. Of the several discretionary procedures in such computer programs, the effects of three were examined and documented: (1) the effect of varying the weights in the pattern conserving techniques; (2) the effect of varying the data influence region; (3) the effect of including wind information in analysis of mass-structure variables. The problem of inserting bogus reports is also examined.

  13. Advanced Numerical Modeling of Turbulent Atmospheric Flows

    NASA Astrophysics Data System (ADS)

    Kühnlein, Christian; Dörnbrack, Andreas; Gerz, Thomas

    The present chapter introduces the method of computational simulation to predict and study turbulent atmospheric flows. This includes a description of the fundamental approach to computational simulation and the practical implementation using the technique of large-eddy simulation. In addition, selected contributions from IPA scientists to computational model development and various examples for applications are given. These examples include homogeneous turbulence, convective boundary layers, heated forest canopy, buoyant thermals, and large-scale flows with baroclinic wave instability.

  14. Potential sensitivity of photosynthesis and isoprene emission to direct radiative effects of atmospheric aerosol pollution

    NASA Astrophysics Data System (ADS)

    Strada, Susanna; Unger, Nadine

    2016-04-01

    A global Earth system model is applied to quantify the impacts of direct anthropogenic aerosol effective radiative forcing on gross primary productivity (GPP) and isoprene emission. The impacts of different pollution aerosol sources (anthropogenic, biomass burning, and non-biomass burning) are investigated by performing sensitivity experiments. The model framework includes all known light and meteorological responses of photosynthesis, but uses fixed canopy structures and phenology. On a global scale, our results show that global land carbon fluxes (GPP and isoprene emission) are not sensitive to pollution aerosols, even under a global decline in surface solar radiation (direct + diffuse) by ˜ 9 %. At a regional scale, GPP and isoprene emission show a robust but opposite sensitivity to pollution aerosols in regions where forested canopies dominate. In eastern North America and Eurasia, anthropogenic pollution aerosols (mainly from non-biomass burning sources) enhance GPP by +5-8 % on an annual average. In the northwestern Amazon Basin and central Africa, biomass burning aerosols increase GPP by +2-5 % on an annual average, with a peak in the northwestern Amazon Basin during the dry-fire season (+5-8 %). The prevailing mechanism varies across regions: light scattering dominates in eastern North America, while a reduction in direct radiation dominates in Europe and China. Aerosol-induced GPP productivity increases in the Amazon and central Africa include an additional positive feedback from reduced canopy temperatures in response to increases in canopy conductance. In Eurasia and northeastern China, anthropogenic pollution aerosols drive a decrease in isoprene emission of -2 to -12 % on an annual average. Future research needs to incorporate the indirect effects of aerosols and possible feedbacks from dynamic carbon allocation and phenology.

  15. Pollution

    ERIC Educational Resources Information Center

    Rowbotham, N.

    1973-01-01

    Presents the material given in one class period in a course on Environmental Studies at Chesterfield School, England. The topics covered include air pollution, water pollution, fertilizers, and insecticides. (JR)

  16. Pollution

    ERIC Educational Resources Information Center

    Terry, Luther L.

    1970-01-01

    Our mechanized environment has produced a variety of man-made pollutants. Prevention of pollution and resulting health hazards is a primary challenge. The Federal Government undertakes a large responsibility in the field of environmental control. (CK)

  17. Modeling Nitrogen Species as Pollutants: Thermochemical Influences.

    PubMed

    Bugler, John; Somers, Kieran P; Simmie, John M; Güthe, Felix; Curran, Henry J

    2016-09-15

    To simulate emissions of nitrogen-containing compounds in practical combustion environments, it is necessary to have accurate values for their thermochemical parameters, as well as accurate kinetic values to describe the rates of their formation and decomposition. Significant disparity is observed in the literature for the former, and we therefore present herein high-accuracy ab initio gas-phase thermochemistry for 60 nitrogenous compounds, many of which are important in the formation and consumption chemistry of NOx species. Several quantum-chemical composite methods (CBS-APNO, G3, and G4) were utilized to derive enthalpies of formation via the atomization method. Entropies and heat capacities were calculated from traditional statistical thermodynamics, with oscillators treated as anharmonic based on ro-vibrational property analyses carried out at the B3LYP/cc-pVTZ level of theory. The use of quantum chemical methods, along with the treatments of anharmonicities and hindered rotors, ensures accurate enthalpy of formation, entropy, and heat capacity values across the temperature range 298.15-3000 K. The implications of these results for atmospheric and combustion modeling are discussed. PMID:27547977

  18. Atmospheric deposition of selected chemicals and their effect on nonpoint-source pollution in the Twin Cities Metropolitan Area, Minnesota

    USGS Publications Warehouse

    Brown, R.G.

    1984-01-01

    The atmospheric contribution to nonpoint-source-runoff pollution of nitrogen, in the form of nitrite-plus-nitrate, and lead was extremely high contributing as much as 84 percent of the runoff load. In contrast, phosphorus and chloride inputs were low averaging of 6 percent of the total runoff load. Future investigations of nonpoint-source pollution in runoff might include collection of data on atmospheric deposition of nitrite-plus-nitrate nitrogen and lead because of the importance of that source of these constituents in runoff.

  19. Observations and Modeling of Tropical Planetary Atmospheres

    NASA Astrophysics Data System (ADS)

    Laraia, Anne

    2016-01-01

    This thesis is a comprised of three different projects within the topic of tropical atmospheric dynamics. First, I analyze observations of thermal radiation from Saturn's atmosphere and from them, determine the latitudinal distribution of ammonia vapor near the 1.5-bar pressure level. The most prominent feature of the observations is the high brightness temperature of Saturn's subtropical latitudes on either side of the equator. After comparing the observations to a microwave radiative transfer model, I find that these subtropical bands require very low ammonia relative humidity below the ammonia cloud layer in order to achieve the high brightness temperatures observed. We suggest that these bright subtropical bands represent dry zones created by a meridionally overturning circulation. Second, I use a dry atmospheric general circulation model to study equatorial superrotation in terrestrial atmospheres. A wide range of atmospheres are simulated by varying three parameters: the pole-equator radiative equilibrium temperature contrast, the convective lapse rate, and the planetary rotation rate. A scaling theory is developed that establishes conditions under which superrotation occurs in terrestrial atmospheres. The scaling arguments show that superrotation is favored when the off-equatorial baroclinicity and planetary rotation rates are low. Similarly, superrotation is favored when the convective heating strengthens, which may account for the superrotation seen in extreme global-warming simulations. Third, I use a moist slab-ocean general circulation model to study the impact of a zonally-symmetric continent on the distribution of monsoonal precipitation. I show that adding a hemispheric asymmetry in surface heat capacity is sufficient to cause symmetry breaking in both the spatial and temporal distribution of precipitation. This spatial symmetry breaking can be understood from a large-scale energetic perspective, while the temporal symmetry breaking requires

  20. Inverse atmospheric radiative transfer problems - A nonlinear minimization search method of solution. [aerosol pollution monitoring

    NASA Technical Reports Server (NTRS)

    Fymat, A. L.

    1976-01-01

    The paper studies the inversion of the radiative transfer equation describing the interaction of electromagnetic radiation with atmospheric aerosols. The interaction can be considered as the propagation in the aerosol medium of two light beams: the direct beam in the line-of-sight attenuated by absorption and scattering, and the diffuse beam arising from scattering into the viewing direction, which propagates more or less in random fashion. The latter beam has single scattering and multiple scattering contributions. In the former case and for single scattering, the problem is reducible to first-kind Fredholm equations, while for multiple scattering it is necessary to invert partial integrodifferential equations. A nonlinear minimization search method, applicable to the solution of both types of problems has been developed, and is applied here to the problem of monitoring aerosol pollution, namely the complex refractive index and size distribution of aerosol particles.

  1. Seasonal Predictability in a Model Atmosphere.

    NASA Astrophysics Data System (ADS)

    Lin, Hai

    2001-07-01

    The predictability of atmospheric mean-seasonal conditions in the absence of externally varying forcing is examined. A perfect-model approach is adopted, in which a global T21 three-level quasigeostrophic atmospheric model is integrated over 21 000 days to obtain a reference atmospheric orbit. The model is driven by a time-independent forcing, so that the only source of time variability is the internal dynamics. The forcing is set to perpetual winter conditions in the Northern Hemisphere (NH) and perpetual summer in the Southern Hemisphere.A significant temporal variability in the NH 90-day mean states is observed. The component of that variability associated with the higher-frequency motions, or climate noise, is estimated using a method developed by Madden. In the polar region, and to a lesser extent in the midlatitudes, the temporal variance of the winter means is significantly greater than the climate noise, suggesting some potential predictability in those regions.Forecast experiments are performed to see whether the presence of variance in the 90-day mean states that is in excess of the climate noise leads to some skill in the prediction of these states. Ensemble forecast experiments with nine members starting from slightly different initial conditions are performed for 200 different 90-day means along the reference atmospheric orbit. The serial correlation between the ensemble means and the reference orbit shows that there is skill in the 90-day mean predictions. The skill is concentrated in those regions of the NH that have the largest variance in excess of the climate noise. An EOF analysis shows that nearly all the predictive skill in the seasonal means is associated with one mode of variability with a strong axisymmetric component.

  2. Model studies of laser absorption computed tomography for remote air pollution measurement

    NASA Technical Reports Server (NTRS)

    Wolfe, D. C., Jr.; Byer, R. L.

    1982-01-01

    Model studies of the potential of laser absorption-computed tomography are presented which demonstrate the possibility of sensitive remote atmospheric pollutant measurements, over kilometer-sized areas, with two-dimensional resolution, at modest laser source powers. An analysis of this tomographic reconstruction process as a function of measurement SNR, laser power, range, and system geometry, shows that the system is able to yield two-dimensional maps of pollutant concentrations at ranges and resolutions superior to those attainable with existing, direct-detection laser radars.

  3. Evidence of the return of past organic pollution in the ocean - a model study

    NASA Astrophysics Data System (ADS)

    Lammel, Gerhard; Stemmler, Irene

    2013-04-01

    Persistent organic pollutants are of great concern because of their long residence time and long-range transport potential in the environment and because they are readily bioaccumulated along food chains and toxic for wildlife and humans. Recovery of the environment from exposure to widespread and persistent chemical pollution is determined by the spatiotemporal emission pattern and storage capacity and transports in environmental compartments. We studied the 3D exposure of the global ocean changing over time in response to historic emissions of polychlorinated biphenyls (PCB) and dichlorodimephenyltrichloromethane (DDT), 1950-2010 using the multicompartment chemistry-transport model MPI-MCTM, which encompasses atmosphere (ECHAM5) and ocean general circulation models (MPIOM), dynamic sub-models for atmospheric aerosols and the marine biogeochemistry, two-dimensional surface compartments (topsoil, vegetation surfaces, ice, and temporal snow cover) and intercompartmental mass exchange process parameterisations [1-3]. The pollution wave received by the surface waters through atmospheric deposition is propagating downward. Besides considerable time lags with respect to the year of peak emission, temporal bimodal exposure to the pollutants is found in mid level and deep waters (200-1500 m) in some areas, e.g. in the western and eastern North Atlantic. This is a consequence of the combination of downward pollution transport by advection, diffusion, and particle settling. It is suggested that the combination of the same processes will lead to re-rise of pollutant concentrations in seawater in other regions in the future. References [1] Guglielmo F, Lammel G, Maier-Reimer E: Global environmental cycling of DDT and gamma-HCH in the 1980s - a study using a coupled atmosphere and ocean general circulation model. Chemosphere 76 (2009) 1509-1517 [2] Stemmler I, Lammel G: Cycling of DDT in the global oceans 1950-2002: World ocean returns the pollutant. Geophys. Res. Lett. 36

  4. PAST AND PRESENT: 50 YEARS OF AIR QUALITY MODELING RESEARCH AND ITS APPLICATIONS BY THE NOAA ATMOSPHERIC SCIENCES MODELING DIVISION

    EPA Science Inventory

    The NOAA Atmospheric Sciences Modeling Division (ASMD) celebrated its Golden Jubilee in September 2005. The partnership between NOAA and EPA began when the Air Pollution Unit of the Public Health Service, which later became part of the EPA, requested the Weather Bureau provide ...

  5. The automated system of detection and research of pollution in the atmosphere

    NASA Astrophysics Data System (ADS)

    Isakova, Anna I.; Smal, Oksana V.; Chistyakova, Liliya K.; Penin, Sergei T.

    2004-02-01

    In the paper, the automated system of data processing (ASDP) for a hardware complex DAN-2, assigned for registration of emission and absorption of optical and the microwave radiation initiated by gas-aerosol pollution in the atmosphere, is presented. The complex DAN-2 has been developed in the Institute of Atsmospheric Optics of the Siberian Branch of the Russian Academy of Science. In the ASDP, a problem of automation of recording processes, storage and processing of the information measured in experiment has been solved. Using in ASDP subsystems of the forecast of optical noise, the forecast of distribution of an impurity in a plume of gas-aerosol emission from industrial plants allows us to carry out the express-analysis of ecological pollution in the inspection zone. Application of a modular principle has created an opportunity to realize all subsystems ASPD independently from each other, thus, they can operate as independently, and in the general complex of programs. As a tool for creation of the system software, the object-oriented instrument of programming Delphi 5.0 has been chosen. It has a number of advantages and distinctive features such as the convenient graphic interface with displaying of calculation results as uniform scrolling tables and graphics, access to the data files, high speed of mathematical calculations, an opportunity of the further expansion and change of the calculation algorithms. Use of the ASPD has allowed us to improve quality of data recording, their processing, and visualization of the processed results. For the first time in the automated system, the complex estimation of ecological situation with use of experimental data in real time has been realized. The ASPD can be used also by other experimental equipment intended for the solution of problems of the atmospheric optics.

  6. Time-space modeling of journey-time exposure to traffic-related air pollution using GIS.

    PubMed

    Gulliver, John; Briggs, David J

    2005-01-01

    Journey-time exposures represent an important, though as yet little-studied, component of human exposure to traffic-related air pollution, potentially with important health effects. Methods for assessing journey-time exposures, either as part of epidemiological studies or for policy assessment, are, however, poorly developed. This paper describes the development and testing of a GIS-based system for modeling human journey-time exposures to traffic-related air pollution: STEMS (Space-Time Exposure Modeling System). The model integrates data on source activity, pollutant dispersion, and travel behavior to derive individual- or group-level exposure measures to atmospheric pollution. The model, which is designed to simulate exposures of people as they move through a changing air pollution field, was developed, validated, and trialed in Northampton, UK. The system currently uses ArcInfo to couple four separate submodels: a source activity/emission model (SATURN), a proprietary atmospheric dispersion model (ADMS-Urban), an empirically derived background air pollution model, and a purposely designed time-activity-based exposure model (TOTEM). This paper describes the structure of the modeling system; presents results of field calibration, validation, and sensitivity analysis; and illustrates the use of the model to analyze journey-time exposures of schoolchildren.

  7. Modeling of Revitalization of Atmospheric Water

    NASA Technical Reports Server (NTRS)

    Coker, Robert; Knox, Jim

    2014-01-01

    The Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project was initiated in September of 2011 as part of the Advanced Exploration Systems (AES) program. Under the ARREM project, testing of sub-scale and full-scale systems has been combined with multiphysics computer simulations for evaluation and optimization of subsystem approaches. In particular, this paper describes the testing and modeling of the water desiccant subsystem of the carbon dioxide removal assembly (CDRA). The goal is a full system predictive model of CDRA to guide system optimization and development.

  8. Long Term Atmospheric and Erosional Pollution As Recorded in Lake Sediments from Yunnan, China

    NASA Astrophysics Data System (ADS)

    Hillman, A. L.; Abbott, M. B.; Yu, J.; Bain, D.; Chiou-Peng, T.

    2014-12-01

    Human activities including agriculture, metallurgy (e.g. mining, processing, smelting), and deforestation have altered cycles of erosion and sedimentation in lake environments for thousands of years. In the Yunnan province of southwestern China, where written records are incomplete, it is unclear when, where, and how much disturbance occurred. Lake sediments offer a means to investigate a wide variety of human activities. Here, we present a lake sediment record from Erhai (25°43'N, 100°12'E) based on trace metal concentrations that reveals substantial atmospheric and erosional pollution to the lake environment over the last 4,000 years. Sediments indicate the initiation of copper-based metallurgy at 3,600 years BP, the existence of which has been debated amongst archaeologists. Beginning 2,000 years BP, sedimentation rates increase and concentrations of metals such as aluminum, titanium, lead, and zinc increase. This is likely linked to increased sediment flux to the lake associated with the initiation of terraced agriculture according to historical documents. The most prominent feature of the record is an abrupt and intense increase in lead, silver, cadmium, and zinc beginning at 700 years BP. The peak of this increase occurs at 600 years BP and is consistent with historical records that the Mongols established the first government operated silver mine in Yunnan. Notably, the concentrations of lead during this time are an order of magnitude greater than modern day levels of pollution.

  9. Lead chromate detected as a source of atmospheric Pb and Cr (VI) pollution

    PubMed Central

    Lee, Pyeong-Koo; Yu, Soonyoung; Chang, Hye Jung; Cho, Hye Young; Kang, Min-Ju; Chae, Byung-Gon

    2016-01-01

    Spherical black carbon aggregates were frequently observed in dust dry deposition in Daejeon, Korea. They were tens of micrometers in diameter and presented a mixture of black carbon and several mineral phases. Transmission electron microscopy (TEM) observations with energy-dispersive X-ray spectroscopy (EDS) and selected area diffraction pattern (SADP) analyses confirmed that the aggregates were compact and included significant amounts of lead chromate (PbCrO4). The compositions and morphologies of the nanosized lead chromate particles suggest that they probably originated from traffic paint used in roads and were combined as discrete minerals with black carbon. Based on Pb isotope analysis and air-mass backward trajectories, the dust in Daejeon received a considerable input of anthropogenic pollutants from heavily industrialized Chinese cities, which implies that long-range transported aerosols containing PbCrO4 were a possible source of the lead and hexavalent chromium levels in East Asia. Lead chromate should be considered to be a source of global atmospheric Pb and Cr(VI) pollution, especially given its toxicity. PMID:27779222

  10. A model for simulating random atmospheres as a function of latitude, season, and time

    NASA Technical Reports Server (NTRS)

    Campbell, J. W.

    1977-01-01

    An empirical stochastic computer model was developed with the capability of generating random thermodynamic profiles of the atmosphere below an altitude of 99 km which are characteristic of any given season, latitude, and time of day. Samples of temperature, density, and pressure profiles generated by the model are statistically similar to measured profiles in a data base of over 6000 rocket and high-altitude atmospheric soundings; that is, means and standard deviations of modeled profiles and their vertical gradients are in close agreement with data. Model-generated samples can be used for Monte Carlo simulations of aircraft or spacecraft trajectories to predict or account for the effects on a vehicle's performance of atmospheric variability. Other potential uses for the model are in simulating pollutant dispersion patterns, variations in sound propagation, and other phenomena which are dependent on atmospheric properties, and in developing data-reduction software for satellite monitoring systems.

  11. Observation and Modeling of Atmospheric Peroxyformic Acid

    NASA Astrophysics Data System (ADS)

    Chen, Z.; Liang, H.; Huang, D.; Huang, L.; Wu, Q.; Wu, H.

    2015-12-01

    The existence and importance of peroxyformic acid (PFA) in the atmosphere has been under controversy. We present here, for the first time, the observation data for PFA from four field measurements carried out in China. These data provided powerful evidence that PFA can stay in the atmosphere, typically in dozens of pptv level. The relationship between PFA and other detected peroxides was examined. The results showed that PFA had a strong positive correlation with its homolog, peroxyacetic acid, due to their similar sources and sinks. Through an evaluation of PFA production and removal rates, we proposed that the reactions between peroxyformyl radical (HC(O)O2) and formaldehyde or the hydroperoxyl radical (HO2) were likely to be the major source and degradation into formic acid (FA) was likely to be the major sink for PFA. Based on a box model evaluation, we proposed that the HC(O)O2 and PFA chemistry was a major source for FA under low NOx conditions. Furthermore, it is found that the impact of the HC(O)O2 and PFA chemistry on radical cycling was dependent on the yield of HC(O)O2 radical from HC(O) + O2 reaction. When this yield exceeded 50%, the HC(O)O2 and PFA chemistry should not be neglected for calculating the radical budget. To make clear the exact importance of HC(O)O2 and PFA chemistry in the atmosphere, further kinetic, field and modeling studies are required.

  12. Empirical modeling of atmospheric deposition in mountainous landscapes.

    PubMed

    Weathers, Kathleen C; Simkin, Samuel M; Lovett, Gary M; Lindberg, Steven E

    2006-08-01

    Atmospheric deposition has long been recognized as an important source of pollutants and nutrients to ecosystems. The need for reliable, spatially explicit estimates of total atmospheric deposition (wet + dry + cloud) is central, not only to air pollution effects researchers, but also for calculation of input-output budgets, and to decision makers faced with the challenge of assessing the efficacy of policy initiatives related to deposition. Although atmospheric deposition continues to represent a critical environmental and scientific issue, current estimates of total deposition have large uncertainties, particularly across heterogeneous landscapes such as montane regions. We developed an empirical modeling approach that predicts total deposition as a function of landscape features. We measured indices of total deposition to the landscapes of Acadia (121 km2) and Great Smoky Mountains (2074 km2) National Parks (USA). Using approximately 300-400 point measurements and corresponding landscape variables at each park, we constructed a statistical (general linear) model relating the deposition index to landscape variables measured in the field. The deposition indices ranged over an order of magnitude, and in response to vegetation type and elevation, which together explained approximately 40% of the variation in deposition. Then, using the independent landscape variables available in GIS data layers, we created a GIS-relevant statistical nitrogen (N) and sulfur (S) deposition model (LandMod). We applied this model to create park-wide maps of total deposition that were scaled to wet and dry deposition data from the closest national network monitoring stations. The resultant deposition maps showed high spatial heterogeneity and a four- to sixfold variation in "hot spots" and "cold spots" of N and S deposition ranging from 3 to 31 kg N x ha(-1) x yr(-1) and from 5 to 42 kg S x ha(-1) x yr(-1) across these park landscapes. Area-weighted deposition was found to be up to 70

  13. Organic chemistry in the atmosphere. [laboratory modeling of Titan atmosphere

    NASA Technical Reports Server (NTRS)

    Sagan, C.

    1974-01-01

    The existence of an at least moderately complex organic chemistry on Titan is stipulated based on clear evidence of methane, and at least presumptive evidence of hydrogen in its atmosphere. The ratio of methane to hydrogen is the highest of any atmosphere in the solar system. Irradiation of hydrogen/methane mixtures produces aromatic and aliphatic hydrocarbons. A very reasonable hypothesis assumes that the red cloud cover of Titan is made of organic chemicals. Two-carbon hydrocarbons experimentally produced from irradiated mixtures of methane, ammonia, water, and hydrogen bear out the possible organic chemistry of the Titanian environment.

  14. A photochemical model of the martian atmosphere.

    PubMed

    Nair, H; Allen, M; Anbar, A D; Yung, Y L; Clancy, R T

    1994-09-01

    The factors governing the amounts of CO, O2, and O3 in the martian atmosphere are investigated using a minimally constrained, one-dimensional photochemical model. We find that the incorporation of temperature-dependent CO2 absorption cross sections leads to an enhancement in the water photolysis rate, increasing the abundance of OH radicals to the point where the model CO abundance is smaller than observed. Good agreement between models and observations of CO, O2, O3, and the escape flux of atomic hydrogen can be achieved, using only gas-phase chemistry, by varying the recommended rate constants for the reactions CO + OH and OH + HO2 within their specified uncertainties. Similar revisions have been suggested to resolve discrepancies between models and observations of the terrestrial mesosphere. The oxygen escape flux plays a key role in the oxygen budget on Mars; as inferred from the observed atomic hydrogen escape, it is much larger than recent calculations of the exospheric escape rate for oxygen. Weathering of the surface may account for the imbalance. Quantification of the escape rates of oxygen and hydrogen from Mars is a worthwhile objective for an upcoming martian upper atmospheric mission. We also consider the possibility that HOx radicals may be catalytically destroyed on dust grains suspended in the atmosphere. Good agreement with the observed CO mixing ratio can be achieved via this mechanism, but the resulting ozone column is much higher than the observed quantity. We feel that there is no need at this time to invoke heterogeneous processes to reconcile models and observations. PMID:11539176

  15. First retrieval of hourly atmospheric radionuclides just after the Fukushima accident by analyzing filter-tapes of operational air pollution monitoring stations

    NASA Astrophysics Data System (ADS)

    Tsuruta, Haruo; Oura, Yasuji; Ebihara, Mitsuru; Ohara, Toshimasa; Nakajima, Teruyuki

    2014-10-01

    No observed data have been found in the Fukushima Prefecture (FP) for the time-series of atmospheric radionuclides concentrations just after the Fukushima Daiichi Nuclear Power Plant (FD1NPP) accident. Accordingly, current estimates of internal radiation doses from inhalation, and atmospheric radionuclide concentrations by atmospheric transport models are highly uncertain. Here, we present a new method for retrieving the hourly atmospheric 137Cs concentrations by measuring the radioactivity of suspended particulate matter (SPM) collected on filter tapes in SPM monitors which were operated even after the accident. This new dataset focused on the period of March 12-23, 2011 just after the accident, when massive radioactive materials were released from the FD1NPP to the atmosphere. Overall, 40 sites of the more than 400 sites in the air quality monitoring stations in eastern Japan were studied. For the first time, we show the spatio-temporal variation of atmospheric 137Cs concentrations in the FP and the Tokyo Metropolitan Area (TMA) located more than 170 km southwest of the FD1NPP. The comprehensive dataset revealed how the polluted air masses were transported to the FP and TMA, and can be used to re-evaluate internal exposure, time-series radionuclides release rates, and atmospheric transport models.

  16. First retrieval of hourly atmospheric radionuclides just after the Fukushima accident by analyzing filter-tapes of operational air pollution monitoring stations.

    PubMed

    Tsuruta, Haruo; Oura, Yasuji; Ebihara, Mitsuru; Ohara, Toshimasa; Nakajima, Teruyuki

    2014-10-22

    No observed data have been found in the Fukushima Prefecture (FP) for the time-series of atmospheric radionuclides concentrations just after the Fukushima Daiichi Nuclear Power Plant (FD1NPP) accident. Accordingly, current estimates of internal radiation doses from inhalation, and atmospheric radionuclide concentrations by atmospheric transport models are highly uncertain. Here, we present a new method for retrieving the hourly atmospheric (137)Cs concentrations by measuring the radioactivity of suspended particulate matter (SPM) collected on filter tapes in SPM monitors which were operated even after the accident. This new dataset focused on the period of March 12-23, 2011 just after the accident, when massive radioactive materials were released from the FD1NPP to the atmosphere. Overall, 40 sites of the more than 400 sites in the air quality monitoring stations in eastern Japan were studied. For the first time, we show the spatio-temporal variation of atmospheric (137)Cs concentrations in the FP and the Tokyo Metropolitan Area (TMA) located more than 170 km southwest of the FD1NPP. The comprehensive dataset revealed how the polluted air masses were transported to the FP and TMA, and can be used to re-evaluate internal exposure, time-series radionuclides release rates, and atmospheric transport models.

  17. Multi-scale modeling of urban air pollution: development of a Street-in-Grid model

    NASA Astrophysics Data System (ADS)

    Kim, Youngseob; Wu, You; Seigneur, Christian; Roustan, Yelva

    2016-04-01

    A new multi-scale model of urban air pollution is presented. This model combines a chemical-transport model (CTM) that includes a comprehensive treatment of atmospheric chemistry and transport at spatial scales greater than 1 km and a street-network model that describes the atmospheric concentrations of pollutants in an urban street network. The street-network model is based on the general formulation of the SIRANE model and consists of two main components: a street-canyon component and a street-intersection component. The street-canyon component calculates the mass transfer velocity at the top of the street canyon (roof top) and the mean wind velocity within the street canyon. The estimation of the mass transfer velocity depends on the intensity of the standard deviation of the vertical velocity at roof top. The effect of various formulations of this mass transfer velocity on the pollutant transport at roof-top level is examined. The street-intersection component calculates the mass transfer from a given street to other streets across the intersection. These mass transfer rates among the streets are calculated using the mean wind velocity calculated for each street and are balanced so that the total incoming flow rate is equal to the total outgoing flow rate from the intersection including the flow between the intersection and the overlying atmosphere at roof top. In the default option, the Leighton photostationary cycle among ozone (O3) and nitrogen oxides (NO and NO2) is used to represent the chemical reactions within the street network. However, the influence of volatile organic compounds (VOC) on the pollutant concentrations increases when the nitrogen oxides (NOx) concentrations are low. To account for the possible VOC influence on street-canyon chemistry, the CB05 chemical kinetic mechanism, which includes 35 VOC model species, is implemented in this street-network model. A sensitivity study is conducted to assess the uncertainties associated with the use of

  18. Quantifying the effects of China's pollution control on atmospheric mercury emissions

    NASA Astrophysics Data System (ADS)

    Zhong, H.

    2014-12-01

    China has conducted series of air pollution control policies to reduce the pollutant emissions. Although not specifically for mercury (Hg), those policies are believed to have co-benefits on atmospheric Hg emission control. On the basis of field-tests data and updated information of energy conservation and emission control, we have developed multiple-year inventories of anthropogenic mercury emissions in China from 2005 to 2012. Three scenarios (scenario 0(S0), scenario 1(S1), scenario 2(S2)) with different emission controls and energy path are designed for prediction of the future Hg emissions for the country. In particular, comprehensive assessments has been conducted to evaluate the evolution of emission factors, recent emission trends, effects of control measures as well as the reliability of our results. The national total emissions of anthropogenic Hg are estimated to increase from 679.0 metric tons (t) in 2005 to 749.8 t in 2012, with the peak at 770.6 t in 2011. The annual growth rate of emissions can then be calculated at 2.1% during 2005-2011, much lower than that of energy consumption or economy of the country. Coal combustion, gold metallurgy and nonferrous metal smelting are the most significant Hg sources of anthropogenic origin, accounting together for 85% of national total emissions. Tightened air pollution controls in China should be important reasons for the smooth emission trends. Compared with 2005, 299 t Hg were reduced in 2010 from power plants, iron and steel smelting, nonferrous-smelting and cement production, benefiting from the improvement of control measures for those sectors. The speciation of Hg emissions is relatively stable for recent years, with the mass fractions of around 55%, 9% and 6% for Hg0, Hg2+ and Hgp respectively. Integrating the policy commitments on energy saving, different from the most conservative case S0, S2 shares the same energy path with S1, but includes more stringent emission control. Under those scenarios, we

  19. Atmospheric mercury pollution at an urban site in central Taiwan: mercury emission sources at ground level.

    PubMed

    Huang, Jiaoyan; Liu, Chia-Kuan; Huang, Ci-Song; Fang, Guor-Cheng

    2012-04-01

    Total gaseous mercury (Hg) (TGM), gaseous oxidized Hg (GOM), and particulate-bound Hg (PBM) concentrations and dry depositions were measured at an urban site in central Taiwan. The concentrations were 6.14±3.91 ng m(-3), 332±153, and 71.1±46.1 pg m(-3), respectively. These results demonstrate high Hg pollution at the ground level in Taiwan. A back trajectory plot shows the sources of the high TGM concentration were in the low atmosphere (<500 m) and approximately 50% of the air masses coming from upper troposphere (>500 m) were associated with low TGM concentrations. This finding implies that Hg is trapped in the low atmosphere and comes from local Hg emission sources. The conditional probability function (CPF) reveals that the plumes of high TGM concentrations come from the south and northwest of the site. The plume from the south comes from two municipal solid waste incinerators (MSWIs). However, no significant Hg point source is located to the northwest of the site; therefore, the plumes from the northwest are hypothesized to be related to the combustion of agricultural waste. Dry deposition fluxes of Hg measured at this site considerably exceeded those measured in North America. Overall, this area is regarded as a highly Hg contaminated area because of local Hg emission sources.

  20. Atmospheric electric field measurements in urban environment and the pollutant aerosol weekly dependence

    NASA Astrophysics Data System (ADS)

    Silva, H. G.; Conceição, R.; Melgão, M.; Nicoll, K.; Mendes, P. B.; Tlemçani, M.; Reis, A. H.; Harrison, R. G.

    2014-11-01

    The weekly dependence of pollutant aerosols in the urban environment of Lisbon (Portugal) is inferred from the records of atmospheric electric field at Portela meteorological station (38°47‧N, 9°08‧W). Measurements were made with a Bendorf electrograph. The data set exists from 1955 to 1990, but due to the contaminating effect of the radioactive fallout during 1960 and 1970s, only the period between 1980 and 1990 is considered here. Using a relative difference method a weekly dependence of the atmospheric electric field is found in these records, which shows an increasing trend between 1980 and 1990. This is consistent with a growth of population in the Lisbon metropolitan area and consequently urban activity, mainly traffic. Complementarily, using a Lomb-Scargle periodogram technique the presence of a daily and weekly cycle is also found. Moreover, to follow the evolution of theses cycles, in the period considered, a simple representation in a colour surface plot representation of the annual periodograms is presented. Further, a noise analysis of the periodograms is made, which validates the results found. Two datasets were considered: all days in the period, and fair-weather days only.

  1. dose-response functions and mapping of risk for materials in urban polluted atmosphere

    NASA Astrophysics Data System (ADS)

    Laurans, E.; Ausset, P.; Chabas, A.; Lefevre, R.-A.

    2003-04-01

    The French field test-site of the United-Nations International Co-operative Programme "Influence of Atmospheric Pollution on Materials, including Historic and Cultural Monuments" (ICP-Materials) located at the top of the Saint-Eustache Church in a pedestrian area in the center of Paris allows to expose various materials (stone, glass, metals, polymers...) and to measure simultaneously the atmospheric parameters (gases, particles, rain, temperature, relative humidity, time of wetness...). The dose-response functions are calculated from the doses recorded on the 30 test-sites of the ICP-Materials network and from the responses analyzed on exposed samples. The critical or acceptable levels and loads are then determined and illustrated by means of mapping. The map of risk for Portland limestone, on the entire French territory and only on Ile-de-France are then given. In conclusion, an improvement of the method is proposed for stone: the mapping of the risk has no meaning except for the area of utilization. Nevertheless, the map of risk for entire Europe concerning materials universally used, like Carrara marble, Portland cement based mortars and Si-Ca-Na modern glass are of better utility.

  2. Mountain cold-trapping increases transfer of persistent organic pollutants from atmosphere to cows' milk.

    PubMed

    Shunthirasingham, Chubashini; Wania, Frank; MacLeod, Matthew; Lei, Ying Duan; Quinn, Cristina L; Zhang, Xianming; Scheringer, Martin; Wegmann, Fabio; Hungerbühler, Konrad; Ivemeyer, Silvia; Heil, Fritz; Klocke, Peter; Pacepavicius, Grazina; Alaee, Mehran

    2013-08-20

    Concentrations of long-lived organic contaminants in snow, soil, lake water, and vegetation have been observed to increase with altitude along mountain slopes. Such enrichment, called "mountain cold-trapping", is attributed to a transition from the atmospheric gas phase to particles, rain droplets, snowflakes, and Earth's surface at the lower temperatures prevailing at higher elevations. Milk sampled repeatedly from cows that had grazed at three different altitudes in Switzerland during one summer was analyzed for a range of persistent organic pollutants. Mountain cold-trapping significantly increased air-to-milk transfer factors of most analytes. As a result, the milk of cows grazing at higher altitudes was more contaminated with substances that have regionally uniform air concentrations (hexachlorobenzene, α-hexachlorocyclohexane, endosulfan sulfate). For substances that have sources, and therefore higher air concentrations, at lower altitudes (polychlorinated biphenyls, γ-hexachlorocyclohexane), alpine milk has lower concentrations, but not as low as would be expected without mountain cold-trapping. Differences in the elevational gradients in soil concentrations and air-to-milk transfer factors highlight that cold-trapping of POPs in pastures is mostly due to increased gas-phase deposition as a result of lower temperatures causing higher uptake capacity of plant foliage, whereas cold-trapping in soils more strongly depends on wet and dry particle deposition. Climatic influences on air-to-milk transfer of POPs needs to be accounted for when using contamination of milk lipids to infer contamination of the atmosphere. PMID:23885857

  3. Hydrocarbon status of soils under atmospheric pollution from a local industrial source

    NASA Astrophysics Data System (ADS)

    Gennadiev, A. N.; Zhidkin, A. P.; Pikovskii, Yu. I.; Kovach, R. G.; Koshovskii, T. S.; Khlynina, N. I.

    2016-09-01

    Contents and compositions of bitumoids, polycyclic aromatic hydrocarbons (PAHs), and free and retained hydrocarbon gases in soils along a transect at different distances from the local industrial source of atmospheric pollution with soot emissions have been studied. The reserves of PAHs progressively decrease when the distance from the source increases. Among the individual PAHs, the most significant decrease is observed for benzo[ a]pyrene, tetraphene, pyrene, chrysene, and anthracene. On plowlands, the share of heavy PAHs—benzo[ ghi]perylene, benzo[ a]pyrene, perylene, etc.—is lower than in the forest soils. In automorphic soils of the park zone adjacent to the industrial zone, the penetration depth of four-, five-, and sixring PAHs from the atmosphere is no more than 25 cm. In soils under natural forest vegetation, heavy PAHs do not penetrate deeper than 5 cm; in tilled soils, their penetration depth coincides with the lower boundary of plow horizons. Analysis of free gases in the soil air revealed hydrocarbons only under forest. From the quantitative and qualitative parameters of the content, reserves, and compositions of different hydrocarbons, the following modification types of hydrocarbon status in the studied soils were revealed: injection, atmosedimentation-injection, atmosedimentation-impact, atmosedimentation-distant, and biogeochemical types.

  4. FT-IR remote sensing of atmospheric species: Application to global change and air pollution

    SciTech Connect

    Vazquez, G.J.

    1995-12-31

    In this contribution, the author describes two applications of Fourier Transform Infrared Spectroscopy to the monitoring of atmospheric compounds. Firstly, the author reports FTIR solar spectroscopy measurements carried out at ground level at NCAR and on airplanes employing a spectrometer of 0.06 cm{sup -1} resolution. Sample atmospheric spectra and fitting examples are presented for key species relevant to stratospheric chemistry and global change: ozone (O{sub 3}), a chlorofluorocarbon (CF{sub 2}Cl{sub 2}), a greenhouse gas (N{sub 2}O), HCl, NO and HNO{sub 3}. Secondly, the author briefly describes urban air pollution measurements at an intersection with heavy traffic in Tucson, AZ. Two FTIR spectrometers of 1 cm{sup -1} resolution were employed to carry out long-path open-path measurements of the CO/CO{sub 2} ratio and SF{sub 6}. Two FEAT and two LPUV instruments were employed for ancillary measurements of CO, CO{sub 2}, NO, and aromatic hydrocarbons. Measurements of CO at two heights and a comparison of CO/CO{sub 2} ratios obtained by FEAT exhaust emission and FTIR ambient air measurements are reported.

  5. CIDGA - Coupling of Interior Dynamic models with Global Atmosphere models

    NASA Astrophysics Data System (ADS)

    Noack, Lena; Plesa, Ana-Catalina; Breuer, Doris

    2010-05-01

    Atmosphere temperatures and in particular the surface temperatures mostly depend on the solar heat flux and the atmospheric composition. The latter can be influenced by interior processes of the planet, i.e. volcanism that releases greenhouse gases such as H2O, CO2 and methane into the atmosphere and plate tectonics through which atmospheric CO2 is recycled via carbonates into the mantle. An increasing concentration of greenhouse gases in the atmosphere results in an increase of the surface temperature. Changes in the surface temperature on the other hand may influence the cooling behaviour of the planet and hence influence its volcanic activity [Phillips et al., 2001]. This feedback relation between mantle convection and atmosphere is not very well understood, since until now mostly either the interior dynamic of a planet or its atmosphere was investigated separately. 2D or 3D mantle convection models to the authors' knowledge haven't been coupled to the atmosphere so far. We have used the 3D spherical simulation code GAIA [Hüttig et al., 2008] including partial melt production and coupled it with the atmosphere module CIDGA using a gray greenhouse model for varying H2O concentrations. This way, not only the influence of mantle dynamics on the atmosphere can be investigated, but also the recoupling effect, that the surface temperature has on the mantle dynamics. So far, we consider one-plate planets without crustal and thus volatile recycling. Phillips et al. [2001] already investigated the coupling effect of the surface temperature on mantle dynamics by using simple parameterized convection models for Venus. In their model a positive feedback mechanism has been observed, i.e., an increase of the surface temperature leads to an increase of partial melt and hence an increase of atmosphere density and surface temperature. Applying our model to Venus, we show that an increase of surface temperature leads not only to an increase of partial melt in the mantle; it also

  6. Atmospheric transmittance model for photosynthetically active radiation

    SciTech Connect

    Paulescu, Marius; Stefu, Nicoleta; Gravila, Paul; Paulescu, Eugenia; Boata, Remus; Pacurar, Angel; Mares, Oana; Pop, Nicolina; Calinoiu, Delia

    2013-11-13

    A parametric model of the atmospheric transmittance in the PAR band is presented. The model can be straightforwardly applied for calculating the beam, diffuse and global components of the PAR solar irradiance. The required inputs are: air pressure, ozone, water vapor and nitrogen dioxide column content, Ångström's turbidity coefficient and single scattering albedo. Comparison with other models and ground measured data shows a reasonable level of accuracy for this model, making it suitable for practical applications. From the computational point of view the calculus is condensed into simple algebra which is a noticeable advantage. For users interested in speed-intensive computation of the effective PAR solar irradiance, a PC program based on the parametric equations along with a user guide are available online at http://solar.physics.uvt.ro/srms.

  7. Model atmospheres - Tool for identifying interstellar features

    NASA Technical Reports Server (NTRS)

    Frisch, P. C.; Slojkowski, S. E.; Rodriguez-Bell, T.; York, D.

    1993-01-01

    Model atmosphere parameters are derived for 14 early A stars with rotation velocities, from optical spectra, in excess of 80 km/s. The models are compared with IUE observations of the stars in regions where interstellar lines are expected. In general, with the assumption of solar abundances, excellent fits are obtained in regions longward of 2580 A, and accurate interstellar equivalent widths can be derived using models to establish the continuum. The fits are poorer at shorter wavelengths, particularly at 2026-2062 A, where the stellar model parameters seem inadequate. Features indicating mass flows are evident in stars with known infrared excesses. In gamma TrA, variability in the Mg II lines is seen over the 5-year interval of these data, and also over timescales as short as 26 days. The present technique should be useful in systematic studies of episodic mass flows in A stars and for stellar abundance studies, as well as interstellar features.

  8. Parallelisation of the Lagrangian atmospheric dispersion model NAME

    NASA Astrophysics Data System (ADS)

    Müller, Eike H.; Ford, Rupert; Hort, Matthew C.; Huggett, Lois; Riley, Graham; Thomson, David J.

    2013-12-01

    The NAME Atmospheric Dispersion Model is a Lagrangian particle model used by the Met Office to predict the propagation and spread of pollutants in the atmosphere. The model is routinely used in emergency response applications, where it is important to obtain results as quickly as possible. This requirement for a short runtime and the increase in core number of commonly available CPUs, such as the Intel Xeon series, has motivated the parallelisation of NAME in the OPENMP shared memory framework. In this work we describe the implementation of this parallelisation strategy in NAME and discuss the performance of the model for different setups. Due to the independence of the model particles, the parallelisation of the main compute intensive loops is relatively straightforward. The random number generator for modelling sub-grid scale turbulent motion needs to be adapted to ensure that different particles use independent sets of random numbers. We find that on Intel Xeon X5680 CPUs the model shows very good strong scaling up to 12 cores in a realistic emergency response application for predicting the dispersion of volcanic ash in the North Atlantic airspace. We implemented a mechanism for asynchronous reading of meteorological data from disk and demonstrate how this can reduce the runtime if disk access plays a significant role in a model run. To explore the performance on different chip architectures we also ported the part of the code which is used for calculating the gamma dose from a cloud of radioactive particles to a graphics processing unit (GPU) using CUDA-C. We were able to demonstrate a significant speedup of around one order of magnitude relative to the serial CPU version.

  9. Modelling of externally mixed particles in the atmosphere

    NASA Astrophysics Data System (ADS)

    ZHU, Shupeng; Sartelet, Karine; Seigneur, Christian

    2014-05-01

    Particles present in the atmosphere have significant impacts on climate as well as on human health. Thus, it is important to accurately simulate and forecast their concentrations. Most commonly used air quality models assume that particles are internally mixed, largely for computational reasons. However, this assumption is disproved by measurements, especially close to sources. In fact, the externally-mixed properties of particles are important for aerosol source identification, radiative effects and particle evolution. In this study, a new size-composition resolved aerosol model is developed. It can solve the aerosol dynamic evolution for external mixtures taking into account the processes of coagulation, condensation and nucleation. Both the size of particles and the mass fraction of each chemical compound are discretized. For a given particle size, particles of different chemical composition may co-exist. Aerosol dynamics is solved in each grid cell by splitting coagulation and condensation/evaporation-nucleation processes. For the condensation/evaporation, surface equilibrium between gas and aerosol is calculated based on ISORROPIA and the newly developed H2O (Hydrophilic/Hydrophobic Organic) Model. Because size and chemical composition sections evolve during condensation/evaporation, concentrations need to be redistributed on fixed sections after condensation/evaporation to be able to use the model in 3 dimensions. This is done based on the numerical scheme HEMEN, which was initially developed for size redistribution. Chemical components can be grouped into several aggregates to reduce computational cost. The 0D model is validated by comparison to results obtained for internally mixed particles and the effect of mixing is investigated for up to 31 species and 4 aggregates. The model will be integrated into the air quality modeling platform POLYPHEMUS to investigate its performance in modeling air quality by comparing with observations during the MEGAPOLI

  10. [Observation of atmospheric pollutants in the urban area of Beibei District, Chongqing].

    PubMed

    Xu, Peng; Hao, Qing-Ju; Ji, Dong-Sheng; Zhang, Jun-Ke; Liu, Zi-Rui; Hu, Bo; Wang, Yue-Si; Jiang, Chang-Sheng

    2014-03-01

    To study the characteristics of atmospheric pollutants in the urban area of Beibei district of Chongqing, the concentrations of the atmospheric pollutants were measured by automatic on-line continuous monitoring equipments from Jan. 2012 to Feb. 2013. The results showed that the concentrations of the pollutants often exceeded the corresponding values of the new National Ambient Air Quality Standards (GB 3095-2012) except SO2. Of these pollutants, PM2.5 was the most serious in this area. The concentrations of the atmospheric pollutants had significant seasonal variation. The concentrations of O3 and O(x) were both the highest in summer and the lowest in winter. The average concentrations of O3 were (36.1 +/- 19.2), (48.8 +/- 32.6), (29.8 +/- 28.6) and (18.2 +/- 15.8) microg x m(-3), and the average O(x) concentrations were (77.6 +/- 20.6), (91.3 +/- 37.6), (77.5 +/- 30.6) and (69.4 +/- 18.2) microg x m(-3) in spring, summer, autumn and winter in 2012, respectively. The concentrations of NO(x) appeared higher in winter and lower in summer, the average concentrations of NO, NO2 and NO(x) were (11.8 +/- 9.4), (42.3 +/- 13.1) and (54.1 +/- 20.8) microg x m(-3) in spring, (8.2 +/- 4.9), (40.5 +/- 9.9) and (48.7 +/- 12.6) microg x m(-3) in summer, (20.7 +/-17.1), (47.2 +/- 14.1) and (67.9 +/- 25.5) microg x m(-3) in autumn, and (30.4 +/- 25.1), (51.2 +/- 15.9), (81.6 +/- 37.9) microg x m(-3) in winter. The concentrations of SO2 appeared higher in spring and winter, and lower in summer and autumn. The concentrations of SO2 were (50.5 +/- 23.3), (26.3 +/- 16.7), (38.8 +/- 18.4) and (53.7 +/- 23.4) microg x m(-3) in spring, summer, autumn and winter, respectively. The concentrations of PM2.5 appeared higher in winter and changed smoothly in other seasons, with the average concentration of (61.4 +/- 28.5), (68.1 +/- 32.5), (61.9 +/- 27.1) and (89.6 +/- 44.2) microg x m(-3) in spring, summer, autumn and winter, respectively. The curves of diurnal variations of O3, O(x), NO, NO

  11. Jacchia-Lineberry upper atmosphere density model

    NASA Technical Reports Server (NTRS)

    Mueller, A. C.

    1982-01-01

    A series of increasingly accurate models which are a careful blend of empirical and theoretical formulae were developed. The exospheric temperature is assumed to be a function of: (1) the average and daily variations in the solar flux, (2) the average and three hourly variations in the geomagnetic index, (3) the angle between the position vector and the axis of the unsymmetric atmospheric bulge, and (4) the angle between the position vector and the geomagnetic pole. The exospheric temperature is related to the density by the solution of the diffusion equilibrium equations for the different constituents of the atmosphere as a function of altitude. Other variations are modeled directly as changes in the density. They are: (1) changes due to the semiannual effect, and (2) changes due to the seasonal latitudinal effect. The causes for these variations are not exactly known but may be modeled sufficiently by empirical formulae. The Jacchia model is assumed to be valid over the altitude range of 90 to 2500 km. The residuals between the observed density from satellite drag observations and the computed densities show the mean relative error to be generally less than 10 percent with occasional peak errors near 50 percent.

  12. Climate Warming and Atmospheric Pollution Effects on Denitrification Rates from Forested Wetlands

    NASA Astrophysics Data System (ADS)

    Enanga, E. M.; Creed, I. F.

    2013-12-01

    Climate controlled biome experiments were conducted to explore the interactive effects of climate warming and changing atmospheric nitrogen deposition rates on gaseous nitrogen (N) loss from forested landscapes. Previous field-based studies showed substantial differences in gaseous N2O efflux among the three topographic positions (upland, ecotone, and wetland) based on gas measurements using static chambers with wetland areas exporting substantially more gaseous N2O than upland areas. We hypothesized that (1) N2O production occurs mainly in the litter-fibric layer of the wetland soil that has a lower carbon to nitrogen (C:N) quotient and more labile carbon than the deeper hemic/peat deposits; and (2) climate warming and atmospheric pollution will have additive or multiplicative effects on N2O effluxes from the wetland soils. Wetland soils were collected and separated into three depths: the litter-fibric layer; 0--30 cm (with C:N quotients < 25, promoting mineralization), and 30--60 cm (with C:N quotients >25, promoting immobilization). A factorial experiment of 2 (+/- labile carbon 0.015 kg/ha/yr) × 3 (0, 15, 30 kg N/ha/yr) was conducted on each of three wetland soil depths. Each 2 × 3 factorial experiment was conducted across a range of temperatures: 10 degrees C, 15 degrees C, 20 degrees C, 25 degrees C, and 30 degrees C. For the highest temperature (30 degrees C), we also examined the potential effect of CO2, by examining ambient versus a doubling of the ambient carbon dioxide (i.e., 750 ppm CO2). The highest N2O efflux was observed in the litter-fibric layer. When all treatments were considered together, the litter-fibric layer had the highest median N2O effluxes (19 kg N2O-N/ha/yr); 0--30 cm depth samples had intermediate effluxes (9 kg N2O-N/ha/yr); and 30--60 cm depth samples had the lowest effluxes (7 kg N2O-N/ha/yr). When the treatments were considered individually, the highest N2O efflux (228 kg N2O-N/ha/yr) was observed at the coolest temperatures (10

  13. A REVIEW OF BIOACCUMULATION MODELING APPROACHES FOR PERSISTENT ORGANIC POLLUTANTS

    EPA Science Inventory

    Persistent organic pollutants and mercury are likely to bioaccumulate in biological components of the environment, including fish and wildlife. The complex and long-term dynamics involved with bioaccumulation are often represented with models. Current scientific developments in t...

  14. Role of sectoral and multi-pollutant emission control strategies in improving atmospheric visibility in the Yangtze River Delta, China.

    PubMed

    Huang, Kan; Fu, Joshua S; Gao, Yang; Dong, Xinyi; Zhuang, Guoshun; Lin, Yanfen

    2014-01-01

    The Community Multi-scale Air Quality modeling system is used to investigate the response of atmospheric visibility to the emission reduction from different sectors (i.e. industries, traffic and power plants) in the Yangtze River Delta, China. Visibility improvement from exclusive reduction of NOx or VOC emission was most inefficient. Sulfate and organic aerosol would rebound if NOx emission was exclusively reduced from any emission sector. The most efficient way to improve the atmospheric visibility was proven to be the multi-pollutant control strategies. Simultaneous emission reductions (20-50%) on NOx, VOC and PM from the industrial and mobile sectors could result in 0.3-1.0 km visibility improvement. And the emission controls on both NOx (85%) and SO2 (90%) from power plants gained the largest visibility improvement of up to 4.0 km among all the scenarios. The seasonal visibility improvement subject to emission controls was higher in summer while lower in the other seasons.

  15. Modeling of air pollution from the power plant ash dumps

    NASA Astrophysics Data System (ADS)

    Aleksic, Nenad M.; Balać, Nedeljko

    A simple model of air pollution from power plant ash dumps is presented, with emission rates calculated from the Bagnold formula and transport simulated by the ATDL type model. Moisture effects are accounted for by assumption that there is no pollution on rain days. Annual mean daily sedimentation rates, calculated for the area around the 'Nikola Tesla' power plants near Belgrade for 1987, show reasonably good agreement with observations.

  16. Modelling the effect of atmospheric nitrogen deposition on marine phytoplankton in the Singapore Strait.

    PubMed

    Sundarambal, P; Tkalich, P; Balasubramanian, R

    2010-01-01

    Atmospheric deposition is an important source of nutrients to the ocean, potentially stimulating primary production, but its relative effect on coastal eutrophication remains largely unknown. This paper presents data generated by the 3-D modelling program NEUTRO to assess the proportion of atmospheric nutrient fluxes, allowing a quantification of the relative contribution of atmospheric and ocean fluxes in the Singapore Strait. This work included an assessment of the importance of high concentration episodic inputs of nitrate-nitrogen associated with transport of polluted air onto the surface water. The NEUTRO model features a nutrient-fuelled food web composed of nutrients, plankton, and dissolved oxygen dynamics. Model simulations show that atmospheric deposition fluxes alone might contribute nitrate-nitrogen mass up to 15% into the Singapore Strait. This amount might be a significant contributor toward regional eutrophication when the system is under nutrient-depleted conditions. Model calibrations for temporal and spatial variability of nutrients qualitatively and quantitatively agreed with available measurements.

  17. Asian pollution climatically modulates mid-latitude cyclones following hierarchical modelling and observational analysis.

    PubMed

    Wang, Yuan; Zhang, Renyi; Saravanan, R

    2014-01-01

    Increasing levels of anthropogenic aerosols in Asia have raised considerable concern regarding its potential impact on the global atmosphere, but the magnitude of the associated climate forcing remains to be quantified. Here, using a novel hierarchical modelling approach and observational analysis, we demonstrate modulated mid-latitude cyclones by Asian pollution over the past three decades. Regional and seasonal simulations using a cloud-resolving model show that Asian pollution invigorates winter cyclones over the northwest Pacific, increasing precipitation by 7% and net cloud radiative forcing by 1.0 W m(-2) at the top of the atmosphere and by 1.7 W m(-2) at the Earth's surface. A global climate model incorporating the diabatic heating anomalies from Asian pollution produces a 9% enhanced transient eddy meridional heat flux and reconciles a decadal variation of mid-latitude cyclones derived from the Reanalysis data. Our results unambiguously reveal a large impact of the Asian pollutant outflows on the global general circulation and climate.

  18. A new mechanism for regional atmospheric chemistry modeling

    NASA Astrophysics Data System (ADS)

    Stockwell, William R.; Kirchner, Frank; Kuhn, Michael; Seefeld, Stephan

    1997-11-01

    A new gas-phase chemical mechanism for the modeling of regional atmospheric chemistry, the "Regional Atmospheric Chemistry Mechanism" (RACM) is presented. The mechanism is intended to be valid for remote to polluted conditions and from the Earth's surface through the upper troposphere. The RACM mechanism is based upon the earlier Regional Acid Deposition Model, version 2 (RADM2) mechanism [Stockwell et al., 1990] and the more detailed Euro-RADM mechanism [Stockwell and Kley, 1994]. The RACM mechanism includes rate constants and product yields from the most recent laboratory measurements, and it has been tested against environmental chamber data. A new condensed reaction mechanism is included for biogenic compounds: isoprene, α-pinene, and d-limonene. The branching ratios for alkane decay were reevaluated, and in the revised mechanism the aldehyde to ketone ratios were significantly reduced. The relatively large amounts of nitrates resulting from the reactions of unbranched alkenes with NO3 are now included, and the production of HO from the ozonolysis of alkenes has a much greater yield. The aromatic chemistry has been revised through the use of new laboratory data. The yield of cresol production from aromatics was reduced, while the reactions of HO, NO3, and O3 with unsaturated dicarbonyl species and unsaturated peroxynitrate are now included in the RACM mechanism. The peroxyacetyl nitrate chemistry and the organic peroxy radical-peroxy radical reactions were revised, and organic peroxy radical +NO3 reactions were added.

  19. Modelling the fate of persistent organic pollutants in europe: parameterization of a gridded distribution model

    SciTech Connect

    Prevedouros, Konstantinos; MacLeod, Matthew; Jones, Kevin C.; Sweetman Andrew J.

    2003-12-01

    A regionally segmented multimedia fate model for the European continent is described together with an illustrative steady-state case study examining the fate of small gamma, Greek-HCH (lindane) based on 1998 emission data. The study builds on the regionally segmented BETR North America model structure and describes the regional segmentation and parameterization for Europe. The European continent is described by a 5 degree x 5 degree grid, leading to 50 regions together with four perimetric boxes representing regions buffering the European environment. Each zone comprises seven compartments including; upper and lower atmosphere, soil, vegetation, fresh water and sediment and coastal water. Inter-regions flows of air and water are described, exploiting information originating from GIS databases and other georeferenced data. The model is primarily designed to describe the fate of Persistent Organic Pollutants (POPs) within the European environment by examining chemical partitioning and de gradation in each region, and inter-region transport either under steady-state conditions or fully dynamically. A test case scenario is presented which examines the fate of estimated spatially resolved atmospheric emissions of lindane throughout Europe within the lower atmosphere and surface soil compartments. In accordance with the predominant wind direction in Europe, the model predicts high concentrations close to the major sources as well as towards Central and Northeast regions. Elevated soil concentrations in Scandinavian soils provide further evidence of the potential of increased scavenging by forests and subsequent accumulation by organic-rich terrestrial surfaces. Initial model predictions have revealed a factor of 5 10 underestimation of lindane concentrations in the atmosphere. This is explained by an underestimation of source strength and/or an underestimation of European background levels. The model presented can further be used to predict deposition fluxes and chemical

  20. High-resolution modelling of health impacts from air pollution using the integrated model system EVA

    NASA Astrophysics Data System (ADS)

    Brandt, Jørgen; Andersen, Mikael S.; Bønløkke, Jakob; Christensen, Jesper H.; Geels, Camilla; Hansen, Kaj M.; Jensen, Steen S.; Ketzel, Matthias; Plejdrup, Marlene S.; Sigsgaard, Torben; Silver, Jeremy D.

    2014-05-01

    A high-resolution assessment of health impacts from air pollution and related external cost has been conducted for Denmark using the integrated EVA model system. The EVA system has been further developed by implementing an air quality model with a 1 km x 1 km resolution covering the whole of Denmark. New developments of the integrated model system will be presented as well as results for health impacts and related external costs over several decades. Furthermore, the sensitivity of health impacts to model resolution will be studied. We have developed an integrated model system EVA (Economic Valuation of Air pollution), based on the impact-pathway chain, to assess the health impacts and health-related economic externalities of air pollution resulting from specific emission sources or sectors. The system is used to support policymaking with respect to emission control. In Brandt et al. (2013a; 2013b), the EVA system was used to assess the impacts in Europe and Denmark from the past, present and future total air pollution levels as well as the contribution from the major anthropogenic emission sectors. The EVA system was applied using the hemispheric chemistry-transport model, the Danish Eulerian Hemispheric Model (DEHM), with nesting capability for higher resolution over Europe (50 km x 50 km) and Northern Europe (16.7 km x 16.7 km). In this study an Urban Background Model (UBM) has been further developed to cover the whole of Denmark with a 1 km x 1 km resolution and the model has been implemented as a part of the integrated model system, EVA. The EVA system is based on the impact-pathway methodology. The site-specific emissions will result (via atmospheric transport and chemistry) in a concentration distribution, which together with detailed population data, are used to estimate the population-level exposure. Using exposure-response functions and economic valuations, the exposure is transformed into impacts on human health and related external costs. In this study

  1. Mesoscale atmospheric modeling for emergency response

    SciTech Connect

    O'Steen, B.L.; Fast, J.D.

    1992-01-01

    Atmospheric transport models for emergency response have traditionally utilized meteorological fields interpolated from sparse data to predict contaminant transport. Often these fields are adjusted to satisfy constraints derived from the governing equations of geophysical fluid dynamics, e.g. mass continuity. Gaussian concentration distributions or stochastic models are then used to represent turbulent diffusion of a contaminant in the diagnosed meteorological fields. The popularity of these models derives from their relative simplicity, ability to make reasonable short-term predictions and, most important, execution speed. The ability to generate a transport prediction for an accidental release from the Savannah River Site in a time frame which will allow protective action to be taken is essential in an emergency response operation.

  2. Mesoscale atmospheric modeling for emergency response

    SciTech Connect

    O`Steen, B.L.; Fast, J.D.

    1992-12-31

    Atmospheric transport models for emergency response have traditionally utilized meteorological fields interpolated from sparse data to predict contaminant transport. Often these fields are adjusted to satisfy constraints derived from the governing equations of geophysical fluid dynamics, e.g. mass continuity. Gaussian concentration distributions or stochastic models are then used to represent turbulent diffusion of a contaminant in the diagnosed meteorological fields. The popularity of these models derives from their relative simplicity, ability to make reasonable short-term predictions and, most important, execution speed. The ability to generate a transport prediction for an accidental release from the Savannah River Site in a time frame which will allow protective action to be taken is essential in an emergency response operation.

  3. Atmosphere - system analysis: models and data

    NASA Astrophysics Data System (ADS)

    Elbern, H.; Bittner, M.

    2003-04-01

    The presentation introduces an AFO2000 section with focus on earth observation issues in a broader sense. Satellite retrieval improvements, chemical data assimilation, humidity and cloud processes, as well as UT/LS chemistry are part of an activity, where the question is adressed how we can observe the earth's atmosphere to attain a picture as comprehensive as possible. With advanced algorithms the problem is adressed, to what extent processes, which are observed in nature, are understood by model simulations. A joint analysis is envisaged, i.e. all available information from measurements are to be combined with complex numerical models, so that a consistent picture of the atmosphere and its evolution is generated. Alternatively, in the case of discrepancies, we are able to identify significant deficiencies in our understanding of the system. In addition to numerical models, this approach requires computationally highly demanding algorithms. These are adopted from Inverse Modelling theory and allow for consistent analyses in an objective sense. Due to its continuous measurements, ENVISAT will play a central role by serving to confront chemistry transport models with data over long periods. Not all trace gases can by far be observed from space. However, under certain conditions, their distribution can be inferred by models in the framework of advanced space-time chemistry data assimilation methods, an inverse technique. Further assimilation efforts include global reconstruction of ozone profiles and of other constituents by numerical modelling and subsequent provision for scientific use. Archived data are also taken to extend the available time series. Efforts are undertaken to improve retrieval algorithms to infer concentration profiles directly from satellite data. Apart from satellite data remote sensing techniques in-situ-observations are also applied during field campaigns. An outstanding problem in atmospheric research, which requires such a combined use of

  4. Developing a smartphone software package for predicting atmospheric pollutant concentrations at mobile locations

    PubMed Central

    Larkin, Andrew; Williams, David E.; Kile, Molly L.; Baird, William M.

    2014-01-01

    Background There is considerable evidence that exposure to air pollution is harmful to health. In the U.S., ambient air quality is monitored by Federal and State agencies for regulatory purposes. There are limited options, however, for people to access this data in real-time which hinders an individual's ability to manage their own risks. This paper describes a new software package that models environmental concentrations of fine particulate matter (PM2.5), coarse particulate matter (PM10), and ozone concentrations for the state of Oregon and calculates personal health risks at the smartphone's current location. Predicted air pollution risk levels can be displayed on mobile devices as interactive maps and graphs color-coded to coincide with EPA air quality index (AQI) categories. Users have the option of setting air quality warning levels via color-coded bars and were notified whenever warning levels were exceeded by predicted levels within 10 km. We validated the software using data from participants as well as from simulations which showed that the application was capable of identifying spatial and temporal air quality trends. This unique application provides a potential low-cost technology for reducing personal exposure to air pollution which can improve quality of life particularly for people with health conditions, such as asthma, that make them more susceptible to these hazards. PMID:26146409

  5. Lidar Monitoring of Mexico City's Atmosphere During High Air Pollution Episodes

    NASA Technical Reports Server (NTRS)

    Quick, C. R., Jr.; Archuleta, F. L.; Hof, D. E.; Karl, R. R., Jr.; Tiee, J. J., Jr.; Eichinger, W. E.; Holtkamp, D. B.; Tellier, L.

    1992-01-01

    Over the last two decades, Mexico City, like many large industrial and populous urban areas, has developed a serious air pollution problem, especially during the winter months when there are frequent temperature inversions and weak winds. The deteriorating air quality is the result of several factors. The basin within which Mexico City lies in Mexico's center of political, administrative and economic activity, generating 34 percent of the gross domestic product and 42 percent of the industrial revenue, and supporting a population which is rapidly approaching the 20 million mark. The basin is surrounded by mountains on three sides which end up preventing rapid dispersal of pollutants. Emissions from the transportation fleet (more than 3 million vehicles) are one of the primary pollution sources, and most are uncontrolled. Catalytic converters are just now working their way into the fleet. The Mexico City Air Quality Research Initiative in an international collaboration project between the Los Alamos National Laboratory and the Mexican Petroleum Institute are dedicated to the investigation of the air quality problem in Mexico City. The main objective of the project is to identify and assess the cost and benefits of major options being proposed to improve the air quality. The project is organized into three main activity areas: (1) modeling and simulation; (2) characterization and measurements; and (3) strategic evaluation.

  6. High-Resolution Modelling of Health Impacts from Air Pollution for Denmark using the Integrated Model System EVA

    NASA Astrophysics Data System (ADS)

    Brandt, Jørgen; Andersen, Mikael S.; Bønløkke, Jakob; Christensen, Jesper H.; Hansen, Kaj M.; Hertel, Ole; Im, Ulas; Jensen, Steen S.; Ketzel, Matthias; Nielsen, Ole-Kenneth; Plejdrup, Marlene S.; Sigsgaard, Torben; Geels, Camilla

    2015-04-01

    We have developed an integrated health impact assessment system EVA (Economic Valuation of Air pollution; Brandt et al., 2013a; 2013b), based on the impact-pathway chain, to assess the health impacts and health-related economic externalities of air pollution resulting from specific emission sources or sectors. The system is used to support policymaking with respect to emission control. The EVA system has previously been used to assess the health impacts based on results from a regional model DEHM (the Danish Eulerian Hemispheric Model; Brandt et al., 2012). In this study we have used a coupling of two chemistry transport models to calculate the air pollution concentration at different scales; the DEHM model to calculate the air pollution levels with a resolution down to 5.6 km x 5.6 km and the UBM model (Urban Background Model ; Berkowicz, 2000; Brandt et al., 2001) to further calculate the air pollution at 1 km x 1 km resolution for Denmark using results from DEHM as boundary conditions. Both the emission data based on the SPREAD model (Plejdrup and Gyldenkærne, 2011) as well as the population density has been represented in the model system with the same high resolution. The new developments of the integrated model system will be presented as well as results for health impacts and related external costs over the years 2006-2014 for Denmark. Furthermore, a sensitivity study of the health impact using coarse and fine resolutions in the model system has been carried out to evaluate the effect of improved description of the geographical population distribution with respect to location of local emissions. References Berkowicz, R., 2000. A Simple Model for Urban Background Pollution. Environmental Monitoring and Assessment, 65, 1/2, 259-267. Brandt, J., J. H. Christensen, L. M. Frohn, F. Palmgren, R. Berkowicz and Z. Zlatev, 2001: "Operational air pollution forecasts from European to local scale". Atmospheric Environment, Vol. 35, Sup. No. 1, pp. S91-S98, 2001 Brandt

  7. A simulation of water pollution model parameter estimation

    NASA Technical Reports Server (NTRS)

    Kibler, J. F.

    1976-01-01

    A parameter estimation procedure for a water pollution transport model is elaborated. A two-dimensional instantaneous-release shear-diffusion model serves as representative of a simple transport process. Pollution concentration levels are arrived at via modeling of a remote-sensing system. The remote-sensed data are simulated by adding Gaussian noise to the concentration level values generated via the transport model. Model parameters are estimated from the simulated data using a least-squares batch processor. Resolution, sensor array size, and number and location of sensor readings can be found from the accuracies of the parameter estimates.

  8. Laser Remote Measurements of atmospheric pollutants (Las-R-Map): UV-Visible Laser system description and data processing

    NASA Astrophysics Data System (ADS)

    Sivakumar, V.; Wyk, H. V.

    Laser radar more popularly known as LIDAR LIght Detection And Ranging is becoming one of the most powerful techniques for active remote sensing of the earth s atmosphere Around the globe several new lidar systems have been developed based on the scientific interest Particularly the DIfferential Absorption Lidar DIAL technique is only one which can provide the better accuracy of measuring atmospheric pollutants Using modern advanced techniques and instrumentation a mobile DIAL system called laser remote measurements of atmospheric pollutants hear after referred as Las-R-Map is designed at National Laser Centre NLC --Pretoria 25 r 45 prime S 28 r 17 prime E Las-R-Map is basically used for measuring atmospheric pollutants applying the principle of absorption by constituents The system designed primarily to focus on the following pollutant measurements such as SO 2 CH 4 CO 2 NO 2 and O 3 In future the system could be used to measure few particulate matter between 2 5 mu m and 10 mu m Benzene Hg 1 3-butadiene H 2 S HF and Volatile Organic Compounds VOC Las-R-map comprises of two different laser sources Alexandrite and CO 2 optical receiver data acquisition and signal processor It uses alexandrite laser in the UV-Visible region from 200 nm to 800 nm and CO 2 laser in the Far-IR region from 9 2 mu m to 10 8 mu m Such two different laser sources make feasibility for studying the wide range of atmospheric pollutants The present paper is focused on technical details

  9. The Atmospheric Radionuclide Transport Model (ARTM) - Validation of a long-term atmospheric dispersion model

    NASA Astrophysics Data System (ADS)

    Hettrich, Sebastian; Wildermuth, Hans; Strobl, Christopher; Wenig, Mark

    2016-04-01

    In the last couple of years, the Atmospheric Radionuclide Transport Model (ARTM) has been developed by the German Federal Office for Radiation Protection (BfS) and the Society for Plant and Reactor Security (GRS). ARTM is an atmospheric dispersion model for continuous long-term releases of radionuclides into the atmosphere, based on the Lagrangian particle model. This model, developed in the first place as a more realistic replacement for the out-dated Gaussian plume models, is currently being optimised for further scientific purposes to study atmospheric dispersion in short-range scenarios. It includes a diagnostic wind field model, allows for the application of building structures and multiple sources (including linear, 2-and 3-dimensional source geometries), and considers orography and surface roughness. As an output it calculates the activity concentration, dry and wet deposition and can model also the radioactive decay of Rn-222. As such, ARTM requires to undergo an intense validation process. While for short-term and short-range models, which were mainly developed for examining nuclear accidents or explosions, a few measurement data-sets are available for validation, data-sets for validating long-term models are very sparse and the existing ones mostly prove to be not applicable for validation. Here we present a strategy for the validation of long-term Lagrangian particle models based on the work with ARTM. In our validation study, the first part we present is a comprehensive analysis of the model sensitivities on different parameters like e.g. (simulation grid size resolution, starting random number, amount of simulation particles, etc.). This study provides a good estimation for the uncertainties of the simulation results and consequently can be used to generate model outputs comparable to the available measurements data at various distances from the emission source. This comparison between measurement data from selected scenarios and simulation results

  10. Lumping, testing, tuning: The invention of an artificial chemistry in atmospheric transport modeling

    NASA Astrophysics Data System (ADS)

    Heymann, Matthias

    Since the late 1950s computer simulation has been used to investigate the transport of pollutants in the atmosphere. About 20 years later also the chemical transformation of atmospheric pollutants was included in computer models of photochemical smog formation. Due to limited knowledge of atmospheric chemistry and due to limited computer capacity, chemical processes in the atmosphere were modeled with the help of simplified chemical models. In these models chemical substances are lumped together forming artificial virtual compounds with virtual characteristics. The paper aims at studying the practices developed in chemical model building and the creation of confidence in these models. Core of the paper will be the analysis of the Urban Airshed Model (UAM) for the Los Angeles region, a pioneering development in the early 1970s. The construction of the UAM involved the "lumping" of chemical processes and extensive testing and tuning. These practices led to a consistent model representation, in which diverse pieces of information fitted and were mutually stabilized. The pragmatic achievement of consistency created confidence, even though empirical tests of the models remained ambiguous and problematic.

  11. [Pollution characteristics and source of the atmospheric fine particles and secondary inorganic compounds at Mount Dinghu in autumn season].

    PubMed

    Liu, Zi-Rui; Wang, Yue-Si; Liu, Quan; Liu, Lu-Ning; Zhang, De-Qiang

    2011-11-01

    Real-time measurements of PM2.5, secondary inorganic compounds in PM2.5 (SO4(2-), NH4(+), and NO3(-)) and related gaseous pollutants were conducted at Mount Dinghu, a regional background station of the Pearl River Delta (PRD), in October and November 2008 by using a conventional R&P TEOM and a system of rapid collection of fine particles and ion chromatography (RCFP-IC). Sources and transportation of atmospheric particles during the experiment were discussed with principal component analysis and backward trajectories calculated using HYSPLIT model. The average daily mass concentrations of PM2.5 were 76.9 microg x m(-3) during sampling period, and average daily mass concentrations of SO4(2-), NH4(+), and NO3(-) were 20.0 microg x m(-3), 6.8 microg x m(-3) and 2.6 microg x m(-3), respectively. The sum of these three secondary inorganic compounds accounted for more than one third of the PM2.5 mass concentration, which had become the major source of atmospheric fine particles at Mount Dinghu. The diurnal variation of PM2.5, SO4(2-), and NH4(+) all showed a "bimodal" distribution with two peaks appeared at 10:00 am and at 16:00 pm, respectively, whereas NO3(-s) howed "single peak" distribution peaked at 10:00 am. The mass concentrations of SO4(2-) in PM2.5 had the similar diurnal variation with that of SO2, SO4(2-) in PM2.5 was mainly transformed from SO2, whereas NO3(-) showed difference diurnal variation with that of NO2, and the second conversion rate of NO2 was far lower than that of SO2. NH4(+) in PM2.5 existed mainly in the form of sulfate, nitrate and chloride. Both of principal component analysis and back trajectory analysis showed that the variations of PM2.5 and secondary inorganic compounds at Mount Dinghu were mainly affected by the long-range transport air mass passed over Guangzhou, Huizhou and other highly industrialized areas which carried air pollutants to the observation site, at the same time local sulfate originated from secondary formation also

  12. Mathematical modeling of stormwater pollution in a tidal embayment

    SciTech Connect

    Najjar, K.F.

    1989-01-01

    It has been recognized for many years that stormwater runoff provides a transport mechanism for non-point pollutants into the nation's waterways. As more watershed areas continue to urbanize, greater increases in pollutant loadings will continue to impact the water quality of the receiving water bodies. In many instances, the pollutant impact exceeds the assimilative capacity of the receiving water. To estimate the potential impacts of stormwater pollution, mathematical models are constructed. In this dissertation, mathematical models have been constructed to estimate the non-point pollutant loadings from an urbanizing area as well as to model the assimilative capacity of the receiving tidal embayment system. The models are capable of simulating the hydrologic aspects as well as the water quality cycles of the system as a function of urbanization. In determining the response of the receiving water system to stormwater loadings, the change in receiving water quality is modeled spatially as well as temporally. The overall model is composed of three subsystem models: a stormwater model, a hydrodynamic tidal model, and a receiving water quality model. Construction of the stormwater model is based on STORM (Storage, Treatment, Overflow, Runoff Model) by the US Army Corps of Engineers. A ground water component to the model has been added to adjust the model for application to the study area, Lakes Bay, New Jersey. The tidal model is developed from a pseudo two-dimensional approach. The methodology utilizes the link-node concept to simulate the embayment system. Solutions to equations of motion and continuity are solved using a finite difference method. The receiving water quality model is a two-dimensional time variable water quality model which is based in a finite segment approach.

  13. Spatial air pollution modelling for a West-African town.

    PubMed

    Gebreab, Sirak Zenebe; Vienneau, Danielle; Feigenwinter, Christian; Bâ, Hâmpaté; Cissé, Guéladio; Tsai, Ming-Yi

    2015-01-01

    Land use regression (LUR) modelling is a common approach used in European and Northern American epidemiological studies to assess urban and traffic related air pollution exposures. Studies applying LUR in Africa are lacking. A need exists to understand if this approach holds for an African setting, where urban features, pollutant exposures and data availability differ considerably from other continents. We developed a parsimonious regression model based on 48-hour nitrogen dioxide (NO2) concentrations measured at 40 sites in Kaédi, a medium sized West-African town, and variables generated in a geographic information system (GIS). Road variables and settlement land use characteristics were found to be important predictors of 48-hour NO2 concentration in the model. About 68% of concentration variability in the town was explained by the model. The model was internally validated by leave-one-out cross-validation and it was found to perform moderately well. Furthermore, its parameters were robust to sampling variation. We applied the model at 100 m pixels to create a map describing the broad spatial pattern of NO2 across Kaédi. In this research, we demonstrated the potential for LUR as a valid, cost-effective approach for air pollution modelling and mapping in an African town. If the methodology were to be adopted by environmental and public health authorities in these regions, it could provide a quick assessment of the local air pollution burden and potentially support air pollution policies and guidelines. PMID:26618306

  14. Photochemical Modeling of the Venus Middle Atmosphere

    NASA Astrophysics Data System (ADS)

    Mills, F. P.; Allen, M. A.; Yung, Y. L.; Lin, A.

    1997-07-01

    The primary photochemical cycle of the Venus middle atmosphere is the photolysis of CO_2 to form CO and oxygen atoms on the dayside, and the re-formation of CO_2 from CO and oxygen via catalytic cycles. Previous modeling used ClO_x [Krasnopolsky & Parshev 1983, Yung & DeMore 1982], SO_x [Winick & Stewart 1980], and HO_x [Sze & McElroy 1975] radicals to catalyze the re-formation of CO_2. These models qualitatively explained the stability of Venus' CO_2 atmosphere, but, despite the powerful catalytic cycles introduced, none could quantitatively explain either the low column abundance of molecular oxygen (two-sigma upper limit of ~ 0.3 - 1.0 x 10(18) molecules cm(-2) depending on the assumed altitude for optical depth unity, Trauger & Lunine 1983) or the intense nightside airglow in the O_2 ((1) Delta ) band. We have developed a revised one-dimensional, steady-state model based on the latest kinetic and photoabsorption data and observations of the abundances of HCl, SO_2, SO, and H_2O. The vertical eddy diffusion profile and the abundance of SO_2 at the lower boundary (58-km altitude) were adjusted to simultaneously reproduce (within the stated error bars and temporal/spatial variability) the retrieved SO profile [Na et al. 1994], the retrieved SO_2 abundance and scale height at the cloud tops [Na et al. 1994], and the retrieved CO profile [Clancy & Muhleman 1991]. Using only gas-phase chemistry, the predicted column abundance of molecular oxygen (above 58-km altitude) has been reduced to ~ 3 x 10(18) molecules cm(-2) by adjusting the rates for selected reactions within their one-sigma uncertainties. Although still larger than the observed upper limit, this column abundance is a factor of 10 smaller than would have been predicted using the Yung & DeMore 1982 model with the currently accepted abundance for HCl (0.4 ppm, Connes et al. 1967, Pollack et al. 1993). Our preliminary results affirm the importance of the ClO_x catalytic cycles in the chemistry of the Venus

  15. Developments in Atmosphere Revitalization Modeling and Simulation

    NASA Technical Reports Server (NTRS)

    Knox, James C.; Kittredge, Kenneth; Xoker, Robert F.; Cummings, Ramona; Gomez, Carlos F.

    2012-01-01

    "NASA's Advanced Exploration Systems (AES) program is pioneering new approaches for rapidly developing prototype systems, demonstrating key capabilities, and validating operational concepts for future human missions beyond Earth orbit" (NASA 2012). These forays beyond the confines of earth's gravity will place unprecedented demands on launch systems. They must not only blast out of earth's gravity well as during the Apollo moon missions, but also launch the supplies needed to sustain a crew over longer periods for exploration missions beyond earth's moon. Thus all spacecraft systems, including those for the separation of metabolic carbon dioxide and water from a crewed vehicle, must be minimized with respect to mass, power, and volume. Emphasis is also placed on system robustness both to minimize replacement parts and ensure crew safety when a quick return to earth is not possible. Current efforts are focused on improving the current state-of-the-art systems utilizing fixed beds of sorbent pellets by evaluating structured sorbents, seeking more robust pelletized sorbents, and examining alternate bed configurations to improve system efficiency and reliability. These development efforts combine testing of sub-scale systems and multi-physics computer simulations to evaluate candidate approaches, select the best performing options, and optimize the configuration of the selected approach, which is then implemented in a full-scale integrated atmosphere revitalization test. This paper describes the development of atmosphere revitalization models and simulations. A companion paper discusses the hardware design and sorbent screening and characterization effort in support of the Atmosphere Revitalization Recovery and Environmental Monitoring (ARREM) project within the AES program.

  16. Atmospheric pollutants in fog and rain events at the northwestern mountains of the Iberian Peninsula.

    PubMed

    Fernández-González, Ricardo; Yebra-Pimentel, Iria; Martínez-Carballo, Elena; Simal-Gándara, Jesús; Pontevedra-Pombal, Xabier

    2014-11-01

    Atmospheric polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) and exist in gas and particle phases, as well as dissolved or suspended in precipitation (fog or rain). While the hydrosphere is the main reservoir for PAHs, the atmosphere serves as the primary route for global transport of PCBs. In this study, fog and rain samples were collected during fourteen events from September 2011 to April 2012 in the Xistral Mountains, a remote range in the NW Iberian Peninsula. PAH compounds [especially of low molecular weight (LMW)] were universally found, but mainly in the fog-water samples. The total PAH concentration in fog-water ranged from non-detected to 216 ng·L(-1) (mean of 45 ng·L(-1)), and was much higher in fall than in winter. Total PAH levels in the rain and fog events varied from non-detected to 1272 and 33 ng·L(-1) for, respectively, LMW and high molecular weight (HMW) PAHs. Diagnostic ratio analysis (LMW PAHs/HMW PAHs) suggested that petroleum combustion was the dominant contributor to PAHs in the area. Total PCB levels in the rain and fog events varied from non-detected to 305 and 91 ng·L(-1) for, respectively, PCBs with 2-3 Cl atoms and 5-10 Cl atoms. PCBs, especially those with 5-10 Cl atoms, were found linked to rain events. The occurrence of the most volatile PCBs, PCBs with 2-3 Cl atoms, is related to wind transport from far away sources, whereas the occurrence of PCBs with 5-10 Cl atoms seems to be related with the increase of its deposition during rainfall at the end of summer and fall. The movement of this fraction of PCBs is facilitated by its binding to air-suspended particles, whose concentrations usually show an increase as the result of a prolonged period of drought in summer.

  17. Atmospheric pollutants in fog and rain events at the northwestern mountains of the Iberian Peninsula.

    PubMed

    Fernández-González, Ricardo; Yebra-Pimentel, Iria; Martínez-Carballo, Elena; Simal-Gándara, Jesús; Pontevedra-Pombal, Xabier

    2014-11-01

    Atmospheric polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) and exist in gas and particle phases, as well as dissolved or suspended in precipitation (fog or rain). While the hydrosphere is the main reservoir for PAHs, the atmosphere serves as the primary route for global transport of PCBs. In this study, fog and rain samples were collected during fourteen events from September 2011 to April 2012 in the Xistral Mountains, a remote range in the NW Iberian Peninsula. PAH compounds [especially of low molecular weight (LMW)] were universally found, but mainly in the fog-water samples. The total PAH concentration in fog-water ranged from non-detected to 216 ng·L(-1) (mean of 45 ng·L(-1)), and was much higher in fall than in winter. Total PAH levels in the rain and fog events varied from non-detected to 1272 and 33 ng·L(-1) for, respectively, LMW and high molecular weight (HMW) PAHs. Diagnostic ratio analysis (LMW PAHs/HMW PAHs) suggested that petroleum combustion was the dominant contributor to PAHs in the area. Total PCB levels in the rain and fog events varied from non-detected to 305 and 91 ng·L(-1) for, respectively, PCBs with 2-3 Cl atoms and 5-10 Cl atoms. PCBs, especially those with 5-10 Cl atoms, were found linked to rain events. The occurrence of the most volatile PCBs, PCBs with 2-3 Cl atoms, is related to wind transport from far away sources, whereas the occurrence of PCBs with 5-10 Cl atoms seems to be related with the increase of its deposition during rainfall at the end of summer and fall. The movement of this fraction of PCBs is facilitated by its binding to air-suspended particles, whose concentrations usually show an increase as the result of a prolonged period of drought in summer. PMID:25129155

  18. Spatial distribution of selected persistent organic pollutants (POPs) in Australia's atmosphere.

    PubMed

    Wang, Xianyu; Kennedy, Karen; Powell, Jennifer; Keywood, Melita; Gillett, Rob; Thai, Phong; Bridgen, Phil; Broomhall, Sara; Paxman, Chris; Wania, Frank; Mueller, Jochen F

    2015-03-01

    A nation-wide passive air sampling campaign recorded concentrations of persistent organic pollutants in Australia's atmosphere in 2012. XAD-based passive air samplers were deployed for one year at 15 sampling sites located in remote/background, agricultural and semi-urban and urban areas across the continent. Concentrations of 47 polychlorinated biphenyls ranged from 0.73 to 72 pg m(-3) (median of 8.9 pg m(-3)) and were consistently higher at urban sites. The toxic equivalent concentration for the sum of 12 dioxin-like PCBs was low, ranging from below detection limits to 0.24 fg m(-3) (median of 0.0086 fg m(-3)). Overall, the levels of polychlorinated biphenyls in Australia were among the lowest reported globally to date. Among the organochlorine pesticides, hexachlorobenzene had the highest (median of 41 pg m(-3)) and most uniform concentration (with a ratio between highest and lowest value ∼5). Bushfires may be responsible for atmospheric hexachlorobenzene levels in Australia that exceeded Southern Hemispheric baseline levels by a factor of ∼4. Organochlorine pesticide concentrations generally increased from remote/background and agricultural sites to urban sites, except for high concentrations of α-endosulfan and DDTs at specific agricultural sites. Concentrations of heptachlor (0.47-210 pg m(-3)), dieldrin (ND-160 pg m(-3)) and trans- and cis-chlordanes (0.83-180 pg m(-3), sum of) in Australian air were among the highest reported globally to date, whereas those of DDT and its metabolites (ND-160 pg m(-3), sum of), α-, β-, γ- and δ-hexachlorocyclohexane (ND-6.7 pg m(-3), sum of) and α-endosulfan (ND-27 pg m(-3)) were among the lowest.

  19. LINEAR MODELS FOR MANAGING SOURCES OF GROUNDWATER POLLUTION.

    USGS Publications Warehouse

    Gorelick, Steven M.; Gustafson, Sven-Ake; ,

    1984-01-01

    Mathematical models for the problem of maintaining a specified groundwater quality while permitting solute waste disposal at various facilities distributed over space are discussed. The pollutants are assumed to be chemically inert and their concentrations in the groundwater are governed by linear equations for advection and diffusion. The aim is to determine a disposal policy which maximises the total amount of pollutants released during a fixed time T while meeting the condition that the concentration everywhere is below prescribed levels.

  20. The prominent role of urban confluences in the local and regional transport of atmospheric pollutants in the Valley of Mexico

    NASA Astrophysics Data System (ADS)

    Jazcilevich, A. D.; Díaz, E. N.; Tatarko, J.; Garcia, A. R.

    2010-12-01

    The meteorological phenomenon known as confluences is especially vigorous in city environments due to the daytime urban heat island effect. Through the analysis of episodes obtained using computational modeling, it is shown not only that confluences strongly influence the local transport of pollution affecting the potential exposure of local population, but also that they enhance the interaction of anthropogenic pollutants generated in Mexico City with natural pollutants emitted in surrounding forests and how confluences provide the necessary convective energy so pollutants are transported on a regional scale

  1. Instabilities in retrieval of atmospheric trace gas profiles caused by the use of atmospheric level models

    NASA Astrophysics Data System (ADS)

    von Clarmann, Thomas; Fischer, Herbert; Oelhaf, Hermann

    1991-07-01

    The onion-peeling-method and the global-fit method algorithms for inverse radiative transfer calculations were applied to atmospheric level models and to layer models to evaluate their applicability in these models. It is shown that, when either of the algorithms is applied to the atmospheric level models (rather than to layer models), the stability of retrieval may significantly deteriorate but that this behavior is due to the choice of the model and not to the retrieval algorithms.

  2. CURRENT METHODS AND RESEARCH STRATEGIES FOR MODELING ATMOSPHERIC MERCURY

    EPA Science Inventory

    The atmospheric pathway of the global mercury cycle is known to be the primary source of mercury contamination to most threatened aquatic ecosystems. Current efforts toward numerical modeling of atmospheric mercury are hindered by an incomplete understanding of emissions, atmosp...

  3. Modelling atmospheric scatterers using spacecraft observations

    NASA Technical Reports Server (NTRS)

    Rages, Kathy A.

    1992-01-01

    Voyager images of Triton indicate considerable spatial variability in the concentration of at least two different scattering components in the atmosphere. Data from high phase angle limb scans were fit to Mie scattering models to derive mean particle sizes, number densities, and vertical extent for both types of scattering material at ten different locations between 15 deg S and 70 deg S. These fits reveal a thin haze at latitudes equatorward of 25-30 deg S. The imaging data can be fit reasonably well by both conservatively scattering and absorbing hazes with particle sizes near 0.18 micron and optical depths of order 0.001-0.01. Rayleigh scattering haze fits the imaging data somewhat less well, and can be totally ruled out by combining the imaging and UVS measurements. At high southern latitudes, Triton displays clouds below an altitude of approximately 8 km, as well as the haze at higher altitudes. The clouds have particle sizes which may range from 0.7-2.0 microns, or may be near 0.25 micron. The atmospheric optical depth poleward of 30 deg S must be generally greater than 0.1, but need not be more than 0.3. Horizontal inhomogeneities are quite noticeable, especially at longitudes east of (i.e., higher than) 180 deg.

  4. An effort for developing a seamless transport modeling and remote sensing system for air pollutants

    NASA Astrophysics Data System (ADS)

    Nakajima, T.; Goto, D.; Dai, T.; Misawa, S.; Uchida, J.; Schutgens, N.; Hashimoto, M.; Oikawa, E.; Takenaka, H.; Tsuruta, H.; Inoue, T.; Higurashi, A.

    2015-12-01

    Wide area of the globe, like Asian region, still suffers from a large emission of air pollutants and cause serious impacts on the earth's climate and the public health of the area. Launch of an international initiative, Climate and Clean Air Coalition (CCAC), is an example of efforts to ease the difficulties by reducing Short-Lived Climate Pollutants (SLCPs), i.e., black carbon aerosol, methane and other short-lived atmospheric materials that heat the earth's system, along with long-lived greenhouse gas mitigation. Impact evaluation of the air pollutants, however, has large uncertainties. We like to introduce a recent effort of projects MEXT/SALSA and MOEJ/S-12 to develop a seamless transport model for atmospheric constituents, NICAM-Chem, that is flexible enough to cover global scale to regional scale by the NICAM nonhydrostatic dynamic core (NICAM), coupled with SPRINTARS aerosol model, CHASER atmospheric chemistry model and with their three computational grid systems, i.e. quasi homogeneous grids, stretched grids and diamond grids. A local ensemble transform Kalman filter/smoother with this modeling system was successfully applied to data from MODIS, AERONET, and CALIPSO for global assimilation/inversion and surface SPM and SO2 air pollution monitoring networks for Japanese area assimilation. My talk will be extended to discuss an effective utility of satellite remote sensing of aerosols using Cloud and Aerosol Imager (CAI) on board the GOSAT satellite and Advanced Himawari Imager (AHI) on board the new third generation geostationary satellite, Himawari-8. The CAI has a near-ultraviolet channel of 380nm with 500m spatial resolution and the AHI has high frequency measurement capability of every 10 minutes. These functions are very effective for accurate land aerosol remote sensing, so that a combination with the developed aerosol assimilation system is promising.

  5. Bjerknes Lecture "Atmospheric Pollution and Climate Change, A Local and Global Perspective"

    NASA Astrophysics Data System (ADS)

    Molina, M. J.

    2004-12-01

    About half of the world's population is now living in urban areas, exposing millions of residents to harmful levels of air pollutants caused mainly by emissions from motor vehicles and industries. Slash-and-burn agricultural practices and forests fires also contribute to worsening air quality on broad regional scales. Emissions from all these fossil fuel and bio-mass burning activities have lead to increases in the amount of atmospheric particulate matter, as well as in the concentration of species such as nitrogen oxides, volatile organic compounds and carbon monoxide. Emissions of these relatively short-lived compounds in turn lead to the formation of tropospheric ozone, which together with particulate matter may also contribute to regional climate change. This deteriorating air quality problem is expected to reach global proportions in the coming decades, with potentially detrimental effects on ecological systems and on human health. On the other hand, improving air quality effectively anywhere in the world requires a holistic approach involving not only science and technology, but also a consideration of economic, social, and political factors.

  6. The polluted atmosphere of the white dwarf NLTT 25792 and the diversity of circumstellar environments

    SciTech Connect

    Vennes, S.; Kawka, A.

    2013-12-10

    We present an analysis of X-shooter spectra of the polluted, hydrogen-rich white dwarf NLTT 25792. The spectra show strong lines of calcium (Ca H and K, near-infrared calcium triplet, and Ca Iλ4226) and numerous lines of iron along with magnesium and aluminum lines from which we draw the abundance pattern. Moreover, the photospheric Ca H and K lines are possibly blended with a circumstellar component shifted by –20 km s{sup –1} relative to the photosphere. A comparison with a sample of four white dwarfs with similar parameters show considerable variations in their abundance patterns, particularly in the calcium to magnesium abundance ratio that varies by a factor of five within this sample. The observed variations, even after accounting for diffusion effects, imply similar variations in the putative accretion source. Also, we find that silicon and sodium are significantly underabundant in the atmosphere of NLTT 25792, a fact that may offer some clues on the nature of the accretion source.

  7. Elemental analysis of aerosols in Tehran's atmosphere using PIXE and identification of pollution sources.

    PubMed

    Esmaili, N; Khashman, S; Lamehi-Rachti, M; Agha Aligol, D; Shokouhi, F; Oliaiy, P; Farmahini Farahani, M

    2014-11-01

    In this study, the proton-induced X-ray emission (PIXE) technique has been applied to measure the elemental composition and concentrations of particulate matter of 220 samples of aerosols in Tehran's atmosphere within a 450-day time interval starting from March 2009 and ending in June 2010, covering all four seasons. PIXE analysis shows the samples are comprised of various elements including Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr, and Pb. Also, to obtain more information about the sources of pollution and to identify the major sources of urban particulate matter, principal component analysis (PCA) was used. Furthermore, micro-PIXE was performed to study individual aerosols in some samples. Results revealed that the concentration of elements originating from vehicle emissions increases three times in winter; whereas the concentration of elements with soil origin remains constant. Based on wind rose maps, it is inferred that the high concentrations of the elements Al, Si, K, Ca, Ti, Mn, and Fe are associated with natural dust brought by winds into Tehran from the west.

  8. A long-range air pollution transport model for eastern north america—I. Sulfur oxides

    NASA Astrophysics Data System (ADS)

    Endlich, R. M.; Nitz, K. C.; Brodzinsky, R.; Bhumralkar, C. M.

    This paper describes a Lagrangian model for simulating long-range air pollution transport over eastern North America. One version (denoted ENAMAP-2S) uses emissions inventories and standard daily weather reports to compute the airborne concentrations of SO 2 and sulfate, and their deposition on the earth's surface. A separate version of the model (ENAMAP-2N) applies to oxides of nitrogen. These versions of the ENAMAP model include the influences of smoothed terrain on the winds, and divide the atmospheric boundary layer into three parts, allowing pollutant emissions to be divided among the layers. Vertical mixing is controlled by diffusion coefficients computed from wind shear, stability, and knowledge of the mixing depth. The transformation and wet and dry deposition rates are based on recently published values. The models have been used to compute monthly average values of concentrations and depositions for January and August 1977. Typical examples are shown. The sensitivity of the output fields of ENAMAP-2S to values selected for input parameters (e.g. transformation rate of SO 2 to sulfate and deposition rates) has been studied; and based on present information, optimum values of the parameters are given. The model results include geographical patterns of pollutant concentration and deposition, and interregional exchange tables that show how much of the pollution in a certain region was emitted locally and how much originated in other specified areas. The simulated monthly airborne concentrations of SO 2 and sulfate are generally within a factor of 2 of measured values.

  9. Modeling atmospheric O 2 over Phanerozoic time

    NASA Astrophysics Data System (ADS)

    Berner, R. A.

    2001-03-01

    A carbon and sulfur isotope mass balance model has been constructed for calculating the variation of atmospheric O 2 over Phanerozoic time. In order to obtain realistic O 2 levels, rapid sediment recycling and O 2-dependent isotope fractionation have been employed by the modelling. The dependence of isotope fractionation on O 2 is based, for carbon, on the results of laboratory photosynthesis experiments and, for sulfur, on the observed relation between oxidation/reduction recycling and S-isotope fractionation during early diagenetic pyrite formation. The range of fractionations used in the modeling agree with measurements of Phanerozoic sediments by others. Results, derived from extensive sensitivity analysis, suggest that there was a positive excursion of O 2 to levels as high as 35% during the Permo-Carboniferous. High O 2 at this time agrees with independent modeling, based on the abundances of organic matter and pyrite in sediments, and with the occurrence of giant insects during this period. The cause of the excursion is believed to be the rise of vascular land plants and the consequent increased production of O 2 by the burial in sediments of lignin-rich organic matter that was resistant to biological decomposition.

  10. Aeras: A next generation global atmosphere model

    DOE PAGES

    Spotz, William F.; Smith, Thomas M.; Demeshko, Irina P.; Fike, Jeffrey A.

    2015-06-01

    Sandia National Laboratories is developing a new global atmosphere model named Aeras that is performance portable and supports the quantification of uncertainties. These next-generation capabilities are enabled by building Aeras on top of Albany, a code base that supports the rapid development of scientific application codes while leveraging Sandia's foundational mathematics and computer science packages in Trilinos and Dakota. Embedded uncertainty quantification (UQ) is an original design capability of Albany, and performance portability is a recent upgrade. Other required features, such as shell-type elements, spectral elements, efficient explicit and semi-implicit time-stepping, transient sensitivity analysis, and concurrent ensembles, were not componentsmore » of Albany as the project began, and have been (or are being) added by the Aeras team. We present early UQ and performance portability results for the shallow water equations.« less

  11. Aeras: A next generation global atmosphere model

    SciTech Connect

    Spotz, William F.; Smith, Thomas M.; Demeshko, Irina P.; Fike, Jeffrey A.

    2015-06-01

    Sandia National Laboratories is developing a new global atmosphere model named Aeras that is performance portable and supports the quantification of uncertainties. These next-generation capabilities are enabled by building Aeras on top of Albany, a code base that supports the rapid development of scientific application codes while leveraging Sandia's foundational mathematics and computer science packages in Trilinos and Dakota. Embedded uncertainty quantification (UQ) is an original design capability of Albany, and performance portability is a recent upgrade. Other required features, such as shell-type elements, spectral elements, efficient explicit and semi-implicit time-stepping, transient sensitivity analysis, and concurrent ensembles, were not components of Albany as the project began, and have been (or are being) added by the Aeras team. We present early UQ and performance portability results for the shallow water equations.

  12. Greenhouse models of the atmosphere of Titan.

    NASA Technical Reports Server (NTRS)

    Pollack, J. B.

    1973-01-01

    The greenhouse effect is calculated for a series of Titanian atmosphere models with different proportions of methane, hydrogen, helium, and ammonia. A computer program is used in temperature-structure calculations based on radiative-convective thermal transfer considerations. A brightness temperature spectrum is derived for Titan and is compared with available observational data. It is concluded that the greenhouse effect on Titan is generated by pressure-induced transitions of methane and hydrogen. The helium-to-hydrogen ratio is found to have a maximum of about 1.5. The surface pressure is estimated to be at least 0.4 atm, with a daytime temperature of about 155 K at the surface. The presence of methane clouds in the upper troposphere is indicated. The clouds have a significant optical depth in the visible, but not in the thermal, infrared.

  13. Modeling pollutant fate and transport in constructed wetlands

    SciTech Connect

    Brown, R.T.; Field, J.J.; Zanoli, M.J.; Crites, R.W.

    1994-12-31

    The Constructed Wetlands Fate and Aquatic Transport Evaluation Model (CWFATE) was developed to evaluate alternative design and operations of the constructed wetlands treatment system (CWTS) at the Sacramento Regional Wastewater Treatment Plant in Elk Grove, California. The model simulates the daily fate and transport of metals and other influent pollutants in an effort to predict CWTS effluent concentrations, removal efficiency, and long-term bioaccumulation of pollutants in sediment, vegetation, organic material, and aquatic organisms. Due to the difficulty of obtaining scientific information for model verification, final calibration is postponed until further field data become available.

  14. Predicting the effect of atmospheric pollution on soil and surface water acidification in the Middle Hills of Nepal.

    PubMed

    Renshaw, M; Collins, R P; Jenkins, A; Arndt, R; Carmichael, G

    1997-12-01

    Rapid population growth and the expansion of South East Asian economies have lead to recent concerns regarding the effects of anthropogenic pollution on the environment. The RAINS-ASIA source-receptor, atmospheric transport model, is used to produce scenarios of future anthropogenic sulphur deposition. This is used as an input to the MAGIC model for prediction of future changes in the hydrochemistry of two catchments of the Likhu Khola watershed in the Middle Hills region of Nepal. Since much of this region is under intense cultivation and the application of mineral fertilisers may be contributing to soil and surface water acidification and loss of soil fertility, a best- and worse-case scenario for fertiliser application are incorporated to assess the overall anthropogenic influence upon soil and surface water acidification. The results indicate a decrease of soil base saturation and streamwater ANC, especially under the worst-case scenario of increased acidic deposition and increased fertiliser use. However, the pH status of soils and surface water are predicted to decrease only marginally as a result of the abundant supply of base cations from the highly weathered bedrock and deep soil. The problem of increased acidification of soils and water at a regional scale, however, should be addressed.

  15. GLANCE - calculatinG heaLth impActs of atmospheric pollutioN in a Changing climatE

    NASA Astrophysics Data System (ADS)

    Vogel, Leif; Faria, Sérgio; Markandya, Anil

    2016-04-01

    Current annual global estimates of premature deaths from poor air quality are estimated in the range of 2.6-4.4 million, and 2050 projections are expected to double against 2010 levels. In Europe, annual economic burdens are estimated at around 750 bn €. Climate change will further exacerbate air pollution burdens; therefore, a better understanding of the economic impacts on human societies has become an area of intense investigation. European research efforts are being carried out within the MACC project series, which started in 2005. The outcome of this work has been integrated into a European capacity for Earth Observation, the Copernicus Atmospheric Monitoring Service (CAMS). In MACC/CAMS, key pollutant concentrations are computed at the European scale and globally by employing chemically-driven advanced transport models. The project GLANCE (calculatinG heaLth impActs of atmospheric pollutioN in a Changing climatE) aims at developing an integrated assessment model for calculating the health impacts and damage costs of air pollution at different physical scales. It combines MACC/CAMS (assimilated Earth Observations, an ensemble of chemical transport models and state of the art ECWMF weather forecasting) with downscaling based on in-situ network measurements. The strengthening of modelled projections through integration with empirical evidence reduces errors and uncertainties in the health impact projections and subsequent economic cost assessment. In addition, GLANCE will yield improved data accuracy at different time resolutions. This project is a multidisciplinary approach which brings together expertise from natural sciences and socio economic fields. Here, its general approach will be presented together with first results for the years 2007 - 2012 on the European scale. The results on health impacts and economic burdens are compared to existing assessments.

  16. Butane extraction of model organic pollutants from water.

    PubMed

    Yang, Chun; Teo, Khay Chuan; Xu, Yan Rong

    2004-04-30

    In this study, n-butane (n-C(4)H(10)), a by-product of the oil refining process, was used as the extractant to remove various model organic pollutants including halogenated hydrocarbons, phenols and aromatic compounds from aqueous matrices. The presence of salt, inorganic acid and dissolved organic materials in the aqueous matrix were found to have little influence on the removal efficiency. High removal efficiencies are readily achievable for a great number of organic pollutants. The removal efficiencies for hydrophobic pollutants were greater than 90% for a single stripping stage for pollutants with a distribution constants (K(D)) greater than 45 and for a n-butane to aqueous phase ratio of 1-5. Results were also reported for the removal of residual butane in treated effluent by combinations of depressurization, air stripping and elevating operating temperature.

  17. A new mathematical model of pollutant dispersion near a building

    SciTech Connect

    Genikhovich, E.L.; Snyder, W.H.

    1994-12-31

    Regulatory models of air pollution in the USA usually account for building effects using a Gaussian description of the pollutant distribution with enhanced vertical and horizontal dispersion coefficients to incorporate the influence of turbulence near clusters of buildings. On the local scale, however, buildings cause dramatic distortions of the mean flow field. These effects are not so important for the description of pollutant distributions from sources located far from buildings, because of the uniformity of the concentration fields. But for sources and receptors located in the vicinity of the buildings, an evaluation of pollutant concentration fields is necessary as a basis for designing of industrial ventilation systems and decision making to protect the environment.

  18. CFD modeling of reactive pollutant dispersion in simplified urban configurations with different chemical mechanisms

    NASA Astrophysics Data System (ADS)

    Sanchez, Beatriz; Santiago, Jose-Luis; Martilli, Alberto; Palacios, Magdalena; Kirchner, Frank

    2016-09-01

    An accurate understanding of urban air quality requires considering a coupled behavior between the dispersion of reactive pollutants and atmospheric dynamics. Currently, urban air pollution is mostly dominated by traffic emission, where nitrogen oxides (NOx) and volatile organic compounds (VOCs) are the primary emitted pollutants. However, modeling reactive pollutants with a large set of chemical reactions, using a computational fluid dynamic (CFD) model, requires a large amount of computational (CPU) time. In this sense, the selection of the chemical reactions needed in different atmospheric conditions becomes essential in finding the best compromise between CPU time and accuracy. The purpose of this work is to assess the differences in NO and NO2 concentrations by considering three chemical approaches: (a) passive tracers (non-reactive), (b) the NOx-O3 photostationary state and (c) a reduced complex chemical mechanism based on 23 species and 25 reactions. The appraisal of the effects of chemical reactions focuses on studying the NO and NO2 dispersion in comparison with the tracer behavior within the street. In turn, the effect of including VOC reactions is also analyzed taking into account several VOC / NOx ratios of traffic emission. Given that the NO and NO2 dispersion can also be affected by atmospheric conditions, such as wind flow or the background concentration from season-dependent pollutants, in this work the influence of wind speeds and background O3 concentrations are studied. The results show that the presence of ozone in the street plays an important role in NO and NO2 concentrations. Therefore, greater differences linked to the chemical approach used are found with higher O3 concentrations and faster wind speeds. This bears relation to the vertical flux as a function of ambient wind speed since it increases the pollutant exchange between the street and the overlying air. This detailed study allows one to ascertain under which atmospheric conditions

  19. Seasonal trends, meteorological impacts, and associated health risks with atmospheric concentrations of gaseous pollutants at an Indian coastal city.

    PubMed

    Mahapatra, Parth Sarathi; Panda, Sipra; Walvekar, P P; Kumar, R; Das, Trupti; Gurjar, B R

    2014-10-01

    This study presents surface ozone (O3) and carbon monoxide (CO) measurements conducted at Bhubaneswar from December 2010 to November 2012 and attempts for the very first time a health risk assessment of the atmospheric trace gases. Seasonal variation in average 24 h O3 and CO shows a distinct winter (December to February) maxima of 38.98 ± 9.32 and 604.51 ± 145.91 ppbv, respectively. O3 and CO characteristics and their distribution were studied in the form of seasonal/diurnal variations, air flow patterns, inversion conditions, and meteorological parameters. The observed winter high is likely due to higher regional emissions, the presence of a shallower boundary layer, and long-range transport of pollutants from the Indo-Gangetic Plain (IGP). Large differences between daytime and nighttime O3 values during winter compared to other seasons suggest that photochemistry is much more active on this site during winter. O3 and CO observations are classified in continental and marine air masses, and continental influence is estimated to increase O3 and CO by up to 20 and 120 ppbv, respectively. Correlation studies between O3 and CO in various seasons indicated the role of CO as one of the O3 precursors. Health risk estimates predict 48 cases of total premature mortality in adults due to ambient tropospheric O3 during the study period. Comparatively low CO concentrations at the site do not lead to any health effects even during winter. This study highlights the possible health risks associated with O3 and CO pollution in Bhubaneswar, but these results are derived from point measurements and should be complemented either with regional scale observations or chemical transport models for use in design of mitigation policies.

  20. Pollution influences on atmospheric composition and chemistry at high northern latitudes: Boreal and California forest fire emissions

    NASA Astrophysics Data System (ADS)

    Singh, H. B.; Anderson, B. E.; Brune, W. H.; Cai, C.; Cohen, R. C.; Crawford, J. H.; Cubison, M. J.; Czech, E. P.; Emmons, L.; Fuelberg, H. E.; Huey, G.; Jacob, D. J.; Jimenez, J. L.; Kaduwela, A.; Kondo, Y.; Mao, J.; Olson, J. R.; Sachse, G. W.; Vay, S. A.; Weinheimer, A.; Wennberg, P. O.; Wisthaler, A.; The Arctas Science Team

    2010-11-01

    We analyze detailed atmospheric gas/aerosol composition data acquired during the 2008 NASA ARCTAS (Arctic Research of the Composition of the Troposphere from Aircraft and Satellites) airborne campaign performed at high northern latitudes in spring (ARCTAS-A) and summer (ARCTAS-B) and in California in summer (ARCTAS-CARB). Biomass burning influences were widespread throughout the ARCTAS campaign. MODIS data from 2000 to 2009 indicated that 2008 had the second largest fire counts over Siberia and a more normal Canadian boreal forest fire season. Near surface arctic air in spring contained strong anthropogenic signatures indicated by high sulfate. In both spring and summer most of the pollution plumes transported to the Arctic region were from Europe and Asia and were present in the mid to upper troposphere and contained a mix of forest fire and urban influences. The gas/aerosol composition of the high latitude troposphere was strongly perturbed at all altitudes in both spring and summer. The reactive nitrogen budget was balanced with PAN as the dominant component. Mean ozone concentrations in the high latitude troposphere were only minimally perturbed (<5 ppb), although many individual pollution plumes sampled in the mid to upper troposphere, and mixed with urban influences, contained elevated ozone (ΔO 3/ΔCO = 0.11 ± 0.09 v/v). Emission and optical characteristics of boreal and California wild fires were quantified and found to be broadly comparable. Greenhouse gas emission estimates derived from ARCTAS-CARB data for the South Coast Air Basin of California show good agreement with state inventories for CO 2 and N 2O but indicate substantially larger emissions of CH 4. Simulations by multiple models of transport and chemistry were found to be broadly consistent with observations with a tendency towards under prediction at high latitudes.

  1. Air pollution modeling at road sides using the operational street pollution model--a case study in Hanoi, Vietnam.

    PubMed

    Hung, Ngo Tho; Ketzel, Matthias; Jensen, Steen Solvang; Oanh, Nguyen Thi Kim

    2010-11-01

    In many metropolitan areas, traffic is the main source of air pollution. The high concentrations of pollutants in streets have the potential to affect human health. Therefore, estimation of air pollution at the street level is required for health impact assessment. This task has been carried out in many developed countries by a combination of air quality measurements and modeling. This study focuses on how to apply a dispersion model to cities in the developing world, where model input data and data from air quality monitoring stations are limited or of varying quality. This research uses the operational street pollution model (OSPM) developed by the National Environmental Research Institute in Denmark for a case study in Hanoi, the capital of Vietnam. OSPM predictions from five streets were evaluated against air pollution measurements of nitrogen oxides (NO(x)), sulfur dioxide (SO2), carbon monoxide (CO), and benzene (BNZ) that were available from previous studies. Hourly measurements and passive sample measurements collected over 3-week periods were compared with model outputs, applying emission factors from previous studies. In addition, so-called "backward calculations" were performed to adapt the emission factors for Hanoi conditions. The average fleet emission factors estimated can be used for emission calculations at other streets in Hanoi and in other locations in Southeast Asia with similar vehicle types. This study also emphasizes the need to further eliminate uncertainties in input data for the street-scale air pollution modeling in Vietnam, namely by providing reliable emission factors and hourly air pollution measurements of high quality.

  2. A photochemical model of the martian atmosphere

    NASA Technical Reports Server (NTRS)

    Nair, Hari; Allen, Mark; Anbar, Ariel D.; Yung, Yuk L; Clancy, R. Todd

    1994-01-01

    The factors governing the amounts of CO, O2, and O3 in the martian atmposphere are investigated using a minimally constrained, one-dimensional photochemical model. We find that the incorporation of temperature-dependent CO2 absorption cross sections leads to an enhancement in the water photolysis rate, increasing the abundance of OH radicals to the point where the model CO abundance is smaller that observed. Good agreement between models and observations of CO, O2, O3, and the escape flux of atomic hydrogen can be achieved, using only gas-phase chemistry, by varying the recommended rate constraints for the reaction CO + OH and OH + HO2 within their specified uncertainties. The oxygen escape flux plays a key role in the oxygen budget on Mars; as inferred from the observed atomic hydrogen escape, it is much larger than recent calculations of the exospheric escape rate for oxygen. Weathering of the surface may account for the imbalance. We also consider the possiblity that HO(x) radicals may be catalytically destroyed on dust grains suspended in the atmosphere. Good agreement with the observed CO mixing ratio can be achieved via this mechanism, but the resulting ozone column is much higher than the observed quantity.

  3. Modelling the effect of severe storms in coastal pollution

    NASA Astrophysics Data System (ADS)

    Grau, A.; Bolea, Y.; Guerra, E.

    2009-09-01

    Modelling and simulation of real events can be very useful to prevent environmental disasters, but these disasters can affect the health and life of human beings; then such tools become definitively necessary for governmental authorities to avoid population risk. In this wok we present a mathematical model that combines the effect of Mediterranean storms together with the effect of wastewater emissary dissolutions at the sea. The emissary model corresponds to a Catalan wastewater plant, the Besos plant in Barcelona. This plant throws the wastewater to the Mediterranean Sea with a 3-km pipe emissary, after a bacteriologically polluted secondary treatment. This polluted water is dissoluted in the salty water, provoking the death of all bacteria agents before they reach the coast. But in difficult conditions under violent storms, with strong East winds, the bacteriological polluted dissolution reaches the shore before the bacteria die and, therefore, a severe coastal pollution is produced. Its consequence can incur in a public health problem and the different governmental agencies activate great alarms to avoid population hazard. Storms modelling permits to evaluate the risk of coastal pollution predicting the wastewater dissolution path and velocity. Several simulations are presented under different storm conditions, making this tool very useful for the environmental protection agencies in the Catalan government.

  4. A new model for polluted soil risk assessment

    NASA Astrophysics Data System (ADS)

    Andretta, M.; Serra, R.; Villani, M.

    2006-08-01

    In this paper, we discuss the most important theoretical aspects of polluted soil Risk Assessment Methodologies, which have been developed in order to evaluate the risk, for the exposed people, connected with the residual contaminant concentration in polluted soil, and we make a short presentation of the major different kinds of risk assessment methodologies. We also underline the relevant role played, in this kind of analysis, by the pollutant transport models. We also describe a new and innovative model, based on the general framework of the so-called Cellular Automata (CA), initially developed in the UE-Esprit Project COLOMBO for the simulation of bioremediation processes. These kinds of models, for their intrinsic "finite and discrete" characteristics, seem to be very well suited for a detailed analysis of the shape of the pollutant sources, the contaminant fates and the evaluation of target in the risk assessment evaluation. In particular, we will describe the future research activities we are going to develop in the area of a strict integration between pollutant fate and transport models and Risk Analysis Methodologies.

  5. Atmospheric oxidation and air pollution in Houston: Lessons from the SHARP 2009 field campaign (Invited)

    NASA Astrophysics Data System (ADS)

    Brune, W. H.; van Duin, D.; Cazorla, M.; Chen, S.; Ren, X.; Mao, J.

    2010-12-01

    Predictive skill for urban ozone pollution is thought to be limited primarily by uncertainties in the emissions of pollution precursor gases such as nitrogen oxides and volatile organic compounds and in the meteorology, particularly the boundary layer height and advection. However, point measurements of the hydroxyl radical (OH) and the hydroperoxyl radical (HO2) have shown that uncertainties in the chemical mechanisms are also important. Other measurements, including those of the OH reactivity (i.e., the inverse of the OH lifetime), help constrain the uncertainties. Two new measurements were made for the first time during SHARP. The first was a direct measurement of the ozone production rate. The second was the laser induced fluorescence measurement of OH using two methods - the usual method of alternating the laser wavelength on and off the OH absorption and a second method of periodically adding an OH reactant, akin to the method used by the chemical ionization / mass spectrometry technique. These two new measurements further constrain the uncertainties. We combine these measurements with others and use simple analyses and photochemical box models to examine the oxidation observed during SHARP 2009 and to put it into context of other field campaigns.

  6. A new model for polluted soil risk assessment

    NASA Astrophysics Data System (ADS)

    Andretta, M.; Villani, M.; Serra, R.

    2003-04-01

    In the last years, the problem of the evaluation of the risk related to soil pollution has became more and more important, all over the world. The increasing number of polluted soils in all the industrialised counties has required the formalisation of well defined methodologies for defining the technical and economical limits of soil remediation. Mainly, these limits are defined in terms of general threshold values that, in some cases, can not be reached even with the so called Best Available Technology (B.A.T.) due for example to the characteristics of the pollutants or of the affected soil, or on the extremely high cost or duration of the remedial intervention. For these reasons, both in the North American Countries and in the European ones, many alternative methodologies based on systematic and scientifically well founded approaches have been developed, in order to determine the real effects of the pollution on the receptor targets. Typically, these methodologies are organised into different levels of detail, the so called "TIERS". Tier 1 is based on a conservative estimation of the risk for the targets, that comes from very general and "worst case" general situations. Tier 2 is based on a more detailed and site specific estimation of the hazard, evaluated by the use of semi-empirical, analytical formulas for the source characterisation, the transport of the pollutant, the target exposition evaluation. Tier 3 is the more detailed and site specific level of application of the risk assessment methodologies and requires the use of numerical methods with many detailed information on the site and on the receptors (e.g.: chemical/physical parameters of the pollutants, hydro-geological data, exposition data, etc.) In this paper, we describe the most important theoretical aspects of the polluted soil risk assessment methodologies and the relevant role played, in this kind of analysis, by the pollutant transport models. In particular, we describe a new and innovative

  7. RSMM: a network language for modeling pollutants in river systems

    SciTech Connect

    Rao, N.B.; Standridge, C.R.; Schnoor, J.L.

    1983-06-01

    Predicting the steady state distribution of pollutants in rivers is important for water quality managers. A new simulation language, the River System Modeling Methodology (RSMM), helps users construct simulation models for analyzing river pollution. In RSMM, a network of nodes and branches represents a river system. Nodes represent elements such as junctions, dams, withdrawals, and pollutant sources; branches represent homogeneous river segments, or reaches. The RSMM processor is a GASP V program. Models can employ either the embedded Streeter-Phelps equations or user supplied equations. The user describes the network diagram with GASP-like input cards. RSMM outputs may be printed or stored in an SDL database. An interface between SDL and DISSPLA provides high quality graphical output.

  8. Lead Isotopes and Temporal Records of Atmospheric Aerosol and Pollutants in Lichens

    NASA Astrophysics Data System (ADS)

    Getty, S. R.; Nash, T.; Asmerom, Y.

    2001-05-01

    Lichens are useful receptors of atmospheric particulate matter (PM) and pollutants due to their retention of body parts (unlike plants), slow growth rates, fairly uniform morphologies, lack of a vascular system, and sessile character over decades to centuries. Lichen biomonitoring has been used widely to map patterns of aerosol deposition, yet few studies have tested whether lichens can preserve a temporal record of airborne PM and pollutants. We show with U-Pb data that epilithic lichens (rock as host) can retain in their porous structure an integrated, decadal-scale history of changing aerosol inputs to desert ecosystems. Three lichens resided along an 80-km transect from a copper smelter (Douglas, AZ) closed in early 1987, to the ENE into adjacent New Mexico. For the radially growing lichen (Xanthoparmelia sp.), U-Pb data were obtained along cm-scale transects in the growth direction on a single thallus. Profiles from lichen rim to interior show increasing [Pb] and [U], or net accumulation with thallus age. Total lead contents are highest near the smelter. In contrast, each lead isotope profile (206Pb/207Pb) is flat during smelter operation, showing low ratios near the smelter (1.152) and high ratios (1.175) 80 km away. This suggests comparable mixtures of crust and smelter lead per locality over decades. Since smelter closure, lichens 80 km from the smelter show a sharp upturn in lead ratio in the recently grown lichen rim, indicating that smelter lead is either dispersed by aeolian recycling, or suppressed in desert soils. The amplitude and position of the isotope signal suggests a soil recovery "half-life" of about 13 yrs, a radial growth rate of 0.57+/-0.1 mm/yr, and a total lichen age of 105+/-18 yrs. Lichens near the smelter have no upturn in isotope ratio, indicating continued aeolian recylcing of lead from soils about 11 yrs after closure. Results at a far-removed desert site (c. New Mexico) also argue that isotope profiles reflect aerosol deposition

  9. Modeling of atmospheric iron processing carried by mineral dust and its deposition to ocean

    NASA Astrophysics Data System (ADS)

    Nickovic, Slobodan; Vukovic, Ana; Vujadinovic, Mirjam

    2014-05-01

    Relatively insoluble iron in dust originating from desert soils increases its solubility after Fe carried by mineral dust is chemically processed by the atmosphere. After dust is deposited deposition to the ocean, soluble Fe as a nutrient could enhance the marine primary production. The atmospheric dust cycle is driven by the atmospheric processes often of smaller, meso-scales. The soil mineralogy of dust emitted from sources determines also how much Fe in the aerosol will be finding. Once Fe is exposed to the atmospheric processes, the atmospheric radiation, clouds and polluted air will chemically affect the iron in dust. Global dust-iron models, having typical horizontal resolutions of 100-300 km which are mostly used to numerically simulate the fate of iron in the atmosphere can provide rather global picture of the dust and iron transport, but not details. Such models often introduce simplistic approximation on the Fe content in dust-productive soils. To simulate the Fe processing we instead implemented a high resolution regional atmospheric dust-iron model with detailed 1km global map for the geographic distribution of Fe content in soil. We also introduced a parameterization of the Fe processing caused by dust mineralogy, cloud processes and solar radiation. We will present results from simulation experiments in order to explore the model capability to reproduce major observed patterns of deposited Fe into the Atlantic cruises.

  10. An empirical assessment of exposure measurement error and effect attenuation in bi-pollutant epidemiologic models

    EPA Science Inventory

    Background: Using multipollutant models to understand combined health effects of exposure to multiple pollutants is becoming more common. However, complex relationships between pollutants and differing degrees of exposure error across pollutants can make health effect estimates f...

  11. An empirical assessment of exposure measurement errors and effect attenuation in bi-pollutant epidemiologic models

    EPA Science Inventory

    Using multipollutant models to understand the combined health effects of exposure to multiple pollutants is becoming more common. However, the complex relationships between pollutants and differing degrees of exposure error across pollutants can make health effect estimates from ...

  12. Radiative characteristics for atmospheric models from lidar sounding and AERONET

    NASA Astrophysics Data System (ADS)

    Sapunov, Maxim; Kuznetsov, Anatoly; Efremenko, Dmitry; Bochalov, Valentin; Melnikova, Irina; Samulenkov, Dimity; Vasilyev, Alexander; Poberovsky, Anatoly; Frantsuzova, Inna

    2016-04-01

    Optical models of atmospheric aerosols above of St. Petersburg are constraint on the base of the results of lidar sounding. The lidar system of the Resource Center "Observatory of environmental safety" of the St. Petersburg University Research Park is situated the city center, Vasilievsky Island. The measurements of the vertical profile of velocity and wind direction in the center of St. Petersburg for 2014 -2015 are fulfilled in addition. Height of laser sounding of aerosols is up to 25 km and wind up to 12 km. Observations are accomplished in the daytime and at night and mapped to vertical profiles of temperature, humidity, wind speed and pressure obtained from radiosounding in Voeikovo (St. Petersburg suburb). Results of wind observations are compared with those of upper-air measurements of meteorological service in Voeikovo. The distance between the points of observation is 25 km. Statistics of wind directions at different heights are identified. The comparison is based on the assumption of homogeneity of the wind field on such a scale. In most cases, good agreement between the observed vertical profiles of wind, obtained by both methods is appeared. However, there were several cases, when the results differ sharply or at high altitudes, or, on the contrary, in the surface layer. The analysis of the impact of wind, temperature, and humidity profiles in the atmosphere on the properties and dynamics of solid impurities is implemented. Comparison with AOT results from AERONET observations in St. Petersburg suburb Peterhof is done. It is shown that diurnal and seasonal variations of optical and morphological parameters of atmospheric aerosols in the pollution cap over the city to a large extent determined by the variability of meteorological parameters. The results of the comparison are presented and possible explanation of the differences is proposed. Optical models of the atmosphere in day and night time in different seasons are constructed from lidar and AERONET

  13. Ag, Ta, Ru, and Ir enrichment in surface soil: Evidence for land pollution of heavy metal from atmospheric deposition

    NASA Astrophysics Data System (ADS)

    Xing, Guangxi; Zhu, Jianguo; Xiong, Zhengqin; Yamasaki, Shin-Ichi

    2004-03-01

    No observation has so far been reported that heavy metal elements from atmospheric deposition were accumulated widely in the surface soil layers. In this research, 28 soil profiles from different climate zones and agro-ecosystems in China were studied, and obvious enrichment of Ag, Ta, Ru, and Ir in the surface soils was discovered. It indicates that pollution of heavy metals emitted into the atmosphere from industrial activities is no longer limited to soils in the vicinity of power, metallurgic, metalworking, and machine-making industries, and they may settle down extensively on land besides cities and industrial regions.

  14. Pollution models and inverse distance weighting: Some critical remarks

    NASA Astrophysics Data System (ADS)

    de Mesnard, Louis

    2013-03-01

    When evaluating the impact of pollution, measurements from remote stations are often weighted by the inverse of distance raised to some nonnegative power (IDW). This is derived from Shepard's method of spatial interpolation (1968). The paper discusses the arbitrary character of the exponent of distance and the problem of monitoring stations that are close to the reference point. From elementary laws of physics, it is determined which exponent of distance should be chosen (or its upper bound) depending on the form of pollution encountered, such as radiant pollution (including radioactivity and sound), air pollution (plumes, puffs, and motionless clouds by using the classical Gaussian model), and polluted rivers. The case where a station is confused with the reference point (or zero distance) is also discussed: in real cases this station imposes its measurement on the whole area regardless of the measurements made by other stations. This is a serious flaw when evaluating the mean pollution of an area. However, it is shown that this is not so in the case of a continuum of monitoring stations, and the measurement at the reference point and for the whole area may differ, which is satisfactory.

  15. Simultaneous measurements of atmospheric pollutants and visibility with a Long-Path DOAS system in urban areas.

    PubMed

    Lee, Jeong Soon; Kim, Young J; Kuk, Bongjae; Geyer, Andreas; Platt, Ulrich

    2005-05-01

    In this paper, the applicability of a Long-Path Differential Optical Absorption Spectroscopy (LP-DOAS) system was checked for the feasibility of the simultaneous measurement of trace gases (such as 03, NO2, SO2, and HCHO) and atmospheric visibility (light extinction by aerosols) in Asian urban areas. Field studies show that an LP-DOAS system can simultaneously measure the key pollutants (such as O3, NO2, SO2, and HCHO) at detection limits in the ppb/sub-ppb range as well as the Mie extinction coefficient with an uncertainty of approximately 0.1 km(-1) at time resolution of a few minutes. It is thus concluded that the use of LP-DOAS system is feasible for simultaneous measurement of gaseous pollutants as well as an atmospheric extinction coefficient which is tightly bound to fine particulate concentration. PMID:15931992

  16. Adsorption and reactions of atmospheric constituents and pollutants on ice particles: an FTIR study

    NASA Astrophysics Data System (ADS)

    Rudakova, A. V.; Marinov, I. L.; Poretskiy, M. S.; Tsyganenko, A. A.

    2009-04-01

    , which act as adsorption sites either as a proton-donor or as a donor of the lone pair of electrons. Such adsorption-induced relaxation explains the dependence of physico-chemical properties of icy particles on the presence of atmospheric gases. Spectra HCN/D2O and ND3/D2O mixed icy films with low (1:10) dopant/water ratios do not manifest any changes in the acidic or basic properties of dangling hydroxyl groups or surface oxygen atoms, but reveal a difference in the proportion between the concentrations of these sites as compared with that for pure water ice. For high dopant concentrations (1:1), the dangling hydroxyls were not observed; the dominant adsorption sites for CO are likely to be the unsaturated oxygen atoms, while serious structural changes occur in the bulk of ices. Ecologically important reactions of atmospheric pollutants such as ozonolysis of ethene, chlorinated ethenes, hydrogen cyanide, and methyl bromide adsorbed on water ice film as well as the influence of UV radiation on this process have been studied in 77 - 200 K temperature range by FTIR spectroscopy. Ozone co-adsorption with ethene or C2H3Cl readily leads to ozonolysis reaction, which also starts for C2H2Cl2 isomers but only at temperatures elevated up to 120 - 150 K. Co-adsorption of O3 with HCN or CH3Br molecules in the dark does not lead to any noticeable spectral changes. Irradiation of HCN or CH3Br deposited on ice films in the presence of ozone leads to appearance of new bands revealing the formation of ozonolysis products. The same "synergetic effect" of simultaneous action of ozone and UV radiation at 77 K, was found for C2H2Cl2 isomers and C2Cl4, which are resistant against O3 even at higher temperatures. The obtained spectral dependence of photo-ozonolysis of C2Cl4 and HCN at 77 K shows that photoexcitation or photodissociation of ozone, evidently, accounts for the observed processes. The surface of ice particles, thus, plays the role of a condenser of atmospheric pollutants and acts

  17. Health benefit modelling and optimization of vehicular pollution control strategies

    NASA Astrophysics Data System (ADS)

    Sonawane, Nayan V.; Patil, Rashmi S.; Sethi, Virendra

    2012-12-01

    This study asserts that the evaluation of pollution reduction strategies should be approached on the basis of health benefits. The framework presented could be used for decision making on the basis of cost effectiveness when the strategies are applied concurrently. Several vehicular pollution control strategies have been proposed in literature for effective management of urban air pollution. The effectiveness of these strategies has been mostly studied as a one at a time approach on the basis of change in pollution concentration. The adequacy and practicality of such an approach is studied in the present work. Also, the assessment of respective benefits of these strategies has been carried out when they are implemented simultaneously. An integrated model has been developed which can be used as a tool for optimal prioritization of various pollution management strategies. The model estimates health benefits associated with specific control strategies. ISC-AERMOD View has been used to provide the cause-effect relation between control options and change in ambient air quality. BenMAP, developed by U.S. EPA, has been applied for estimation of health and economic benefits associated with various management strategies. Valuation of health benefits has been done for impact indicators of premature mortality, hospital admissions and respiratory syndrome. An optimization model has been developed to maximize overall social benefits with determination of optimized percentage implementations for multiple strategies. The model has been applied for sub-urban region of Mumbai city for vehicular sector. Several control scenarios have been considered like revised emission standards, electric, CNG, LPG and hybrid vehicles. Reduction in concentration and resultant health benefits for the pollutants CO, NOx and particulate matter are estimated for different control scenarios. Finally, an optimization model has been applied to determine optimized percentage implementation of specific

  18. Complex Physiological Response of Norway Spruce to Atmospheric Pollution - Decreased Carbon Isotope Discrimination and Unchanged Tree Biomass Increment.

    PubMed

    Čada, Vojtěch; Šantrůčková, Hana; Šantrůček, Jiří; Kubištová, Lenka; Seedre, Meelis; Svoboda, Miroslav

    2016-01-01

    Atmospheric pollution critically affects forest ecosystems around the world by directly impacting the assimilation apparatus of trees and indirectly by altering soil conditions, which subsequently also leads to changes in carbon cycling. To evaluate the extent of the physiological effect of moderate level sulfate and reactive nitrogen acidic deposition, we performed a retrospective dendrochronological analysis of several physiological parameters derived from periodic measurements of carbon stable isotope composition ((13)C discrimination, intercellular CO2 concentration and intrinsic water use efficiency) and annual diameter increments (tree biomass increment, its inter-annual variability and correlation with temperature, cloud cover, precipitation and Palmer drought severity index). The analysis was performed in two mountain Norway spruce (Picea abies) stands of the Bohemian Forest (Czech Republic, central Europe), where moderate levels of pollution peaked in the 1970s and 1980s and no evident impact on tree growth or link to mortality has been reported. The significant influence of pollution on trees was expressed most sensitively by a 1.88‰ reduction of carbon isotope discrimination (Δ(13)C). The effects of atmospheric pollution interacted with increasing atmospheric CO2 concentration and temperature. As a result, we observed no change in intercellular CO2 concentrations (Ci), an abrupt increase in water use efficiency (iWUE) and no change in biomass increment, which could also partly result from changes in carbon partitioning (e.g., from below- to above-ground). The biomass increment was significantly related to Δ(13)C on an individual tree level, but the relationship was lost during the pollution period. We suggest that this was caused by a shift from the dominant influence of the photosynthetic rate to stomatal conductance on Δ(13)C during the pollution period. Using biomass increment-climate correlation analyses, we did not identify any clear pollution

  19. Complex Physiological Response of Norway Spruce to Atmospheric