Science.gov

Sample records for estimating atmospheric pollutant

  1. Spectral estimation of global levels of atmospheric pollutants.

    PubMed

    Fernández-Macho, Javier

    2011-10-01

    Underlying levels of atmospheric pollutants, assumed to be governed by smoothing mechanisms due to atmospheric dispersion, can be estimated from global emissions source databases on greenhouse gases and ozone-depleting compounds. However, spatial data may be contaminated with noise or even missing or zero-valued at many locations. Therefore, a problem that arises is how to extract the underlying smooth levels. This paper sets out a structural spatial model that assumes data evolve across a global grid constrained by second-order smoothing restrictions. The frequency-domain approach is particularly suitable for global datasets, reduces the computational burden associated with two-dimensional models and avoids cumbersome zero-inflated skewed distributions. Confidence intervals of the underlying levels are also obtained. An application to the estimation of global levels of atmospheric pollutants from anthropogenic emissions illustrates the technique which may also be useful in the analysis of other environmental datasets of similar characteristics.

  2. 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.

  3. 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)

  4. 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.

  5. 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.

  6. Remote measurement of atmospheric pollutants

    NASA Technical Reports Server (NTRS)

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

    1979-01-01

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

  7. Transboundary atmospheric lead pollution.

    PubMed

    Erel, Yigal; Axelrod, Tamar; Veron, Alain; Mahrer, Yitzak; Katsafados, Petros; Dayan, Uri

    2002-08-01

    A high-temporal resolution collection technique was applied to refine aerosol sampling in Jerusalem, Israel. Using stable lead isotopes, lead concentrations, synoptic data, and atmospheric modeling, we demonstrate that lead detected in the atmosphere of Jerusalem is not only anthropogenic lead of local origin but also lead emitted in other countries. Fifty-seven percent of the collected samples contained a nontrivial fraction of foreign atmospheric lead and had 206Pb/207Pb values which deviated from the local petrol-lead value (206Pb/207Pb = 1.113) by more than two standard deviations (0.016). Foreign 206Pb/207Pb values were recorded in Jerusalem on several occasions. The synoptic conditions on these dates and reported values of the isotopic composition of lead emitted in various countries around Israel suggest that the foreign lead was transported to Jerusalem from Egypt, Turkey, and East Europe. The average concentration of foreign atmospheric lead in Jerusalem was 23 +/- 17 ng/m3, similar to the average concentration of local atmospheric lead, 21 +/- 18 ng/ m3. Hence, the load of foreign atmospheric lead is similar to the load of local atmospheric lead in Jerusalem.

  8. 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

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. Archives of Atmospheric Lead Pollution

    NASA Astrophysics Data System (ADS)

    Weiss, Dominik; Shotyk, William; Kempf, Oliver

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

  14. [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

  15. 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

  16. NEW APPROACHES: Students `weigh' atmospheric pollution

    NASA Astrophysics Data System (ADS)

    Caporaloni, Marina

    1998-07-01

    By using a portable fan and filters of various materials students have devised simple means of measuring the mass concentration of particles in a polluted urban atmosphere. Comparison of students' data with official data is instructive.

  17. Estimation of exposure to atmospheric pollutants during pregnancy integrating space-time activity and indoor air levels: Does it make a difference?

    PubMed

    Ouidir, Marion; Giorgis-Allemand, Lise; Lyon-Caen, Sarah; Morelli, Xavier; Cracowski, Claire; Pontet, Sabrina; Pin, Isabelle; Lepeule, Johanna; Siroux, Valérie; Slama, Rémy

    2015-11-01

    Studies of air pollution effects during pregnancy generally only consider exposure in the outdoor air at the home address. We aimed to compare exposure models differing in their ability to account for the spatial resolution of pollutants, space-time activity and indoor air pollution levels. We recruited 40 pregnant women in the Grenoble urban area, France, who carried a Global Positioning System (GPS) during up to 3 weeks; in a subgroup, indoor measurements of fine particles (PM2.5) were conducted at home (n=9) and personal exposure to nitrogen dioxide (NO2) was assessed using passive air samplers (n=10). Outdoor concentrations of NO2, and PM2.5 were estimated from a dispersion model with a fine spatial resolution. Women spent on average 16 h per day at home. Considering only outdoor levels, for estimates at the home address, the correlation between the estimate using the nearest background air monitoring station and the estimate from the dispersion model was high (r=0.93) for PM2.5 and moderate (r=0.67) for NO2. The model incorporating clean GPS data was less correlated with the estimate relying on raw GPS data (r=0.77) than the model ignoring space-time activity (r=0.93). PM2.5 outdoor levels were not to moderately correlated with estimates from the model incorporating indoor measurements and space-time activity (r=-0.10 to 0.47), while NO2 personal levels were not correlated with outdoor levels (r=-0.42 to 0.03). In this urban area, accounting for space-time activity little influenced exposure estimates; in a subgroup of subjects (n=9), incorporating indoor pollution levels seemed to strongly modify them.

  18. Estimation of exposure to atmospheric pollutants during pregnancy integrating space-time activity and indoor air levels: does it make a difference?

    PubMed Central

    Marion, OUIDIR; Lise, GIORGIS-ALLEMAND; Sarah, LYON-CAEN; Xavier, MORELLI; Claire, CRACOWSKI; Sabrina, PONTET; Isabelle, PIN; Johanna, LEPEULE; Valérie, SIROUX; Rémy, SLAMA

    2016-01-01

    Studies of air pollution effects during pregnancy generally only consider exposure in the outdoor air at the home address. We aimed to compare exposure models differing in their ability to account for the spatial resolution of pollutants, space-time activity and indoor air pollution levels. We recruited 40 pregnant women in the Grenoble urban area, France, who carried a Global Positioning System (GPS) during up to 3 weeks; in a subgroup, indoor measurements of fine particles (PM2.5) were conducted at home (n=9) and personal exposure to nitrogen dioxide (NO2) was assessed using passive air samplers (n=10). Outdoor concentrations of NO2, and PM2.5 were estimated from a dispersion model with a fine spatial resolution. Women spent on average 16 h per day at home. Considering only outdoor levels, for estimates at the home address, the correlation between the estimate using the nearest background air monitoring station and the estimate from the dispersion model was high (r=0.93) for PM2.5 and moderate (r=0.67) for NO2. The model incorporating clean GPS data was less correlated with the estimate relying on raw GPS data (r=0.77) than the model ignoring space-time activity (r=0.93). PM2.5 outdoor levels were not to moderately correlated with estimates from the model incorporating indoor measurements and space-time activity (r=−0.10 to 0.47), while NO2 personal levels were not correlated with outdoor levels (r=−0.42 to 0.03). In this urban area, accounting for space-time activity little influenced exposure estimates; in a subgroup of subjects (n=9), incorporating indoor pollution levels seemed to strongly modify them. PMID:26300245

  19. 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.

  20. Laser Remote Sensing of Atmospheric Pollutants.

    DTIC Science & Technology

    1984-09-30

    of Cross-Correlation and Signal Averaging Appendix B: Laser Remote Sensing of Atmospheric Ammonia using a 33 C02 LIDAR System Ac-’,i- n For AVE...of CO2 differential-absorption LIDAR (DIAL) for the remote sensing of atmospheric pollutants was continued during FY84 and consisted of two...individual LIDAR signals and then taking the ratios of the averaged signals in order to deduce the differential-absorption value. This is in contrast to

  1. 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…

  2. 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.

  3. Estimation of errors in the inverse modeling of accidental release of atmospheric pollutant: Application to the reconstruction of the cesium-137 and iodine-131 source terms from the Fukushima Daiichi power plant

    NASA Astrophysics Data System (ADS)

    Winiarek, Victor; Bocquet, Marc; Saunier, Olivier; Mathieu, Anne

    2012-03-01

    A major difficulty when inverting the source term of an atmospheric tracer dispersion problem is the estimation of the prior errors: those of the atmospheric transport model, those ascribed to the representativity of the measurements, those that are instrumental, and those attached to the prior knowledge on the variables one seeks to retrieve. In the case of an accidental release of pollutant, the reconstructed source is sensitive to these assumptions. This sensitivity makes the quality of the retrieval dependent on the methods used to model and estimate the prior errors of the inverse modeling scheme. We propose to use an estimation method for the errors' amplitude based on the maximum likelihood principle. Under semi-Gaussian assumptions, it takes into account, without approximation, the positivity assumption on the source. We apply the method to the estimation of the Fukushima Daiichi source term using activity concentrations in the air. The results are compared to an L-curve estimation technique and to Desroziers's scheme. The total reconstructed activities significantly depend on the chosen method. Because of the poor observability of the Fukushima Daiichi emissions, these methods provide lower bounds for cesium-137 and iodine-131 reconstructed activities. These lower bound estimates, 1.2 × 1016 Bq for cesium-137, with an estimated standard deviation range of 15%-20%, and 1.9 - 3.8 × 1017 Bq for iodine-131, with an estimated standard deviation range of 5%-10%, are of the same order of magnitude as those provided by the Japanese Nuclear and Industrial Safety Agency and about 5 to 10 times less than the Chernobyl atmospheric releases.

  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. 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

  6. ESTIMATING URBAN WET WEATHER POLLUTANT LOADING

    EPA Science Inventory

    This paper presents procedures for estimating pollutant loads emanating from wet-weather flow discharge in urban watersheds. Equations are presented for: annual volume of litter and floatables; the quantity of sand from highway runoff; the quantity of dust-and-dirt accumulation ...

  7. 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.

  8. 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)

  9. 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.

  10. Transport of organic pollutants and their atmospheric fates

    NASA Astrophysics Data System (ADS)

    Raff, Jonathan Daniel

    Suspended sediment samples from ˜30 locations along the Mississippi River and six of its major tributaries collected between 2002 and 2003 were found to contain high levels of persistent organic pollutants (POPs) such as toxaphene and polybrominated diphenyl ether (PBDE) flame retardants. We found that the loss of these pollutants from terrestrial source areas via rivers is insignificant compared to loss via volatilization into the atmosphere. Analysis of pollutants in a sediment core from Siskiwit lake on Isle Royale, a remote island in Lake Superior support the theory that PBDEs undergo long-range atmospheric transport from source areas to regions where they were never used. The congener pattern of PBDEs in the lake sediment suggests that multiple processes act to remove PBDEs from the atmosphere after they are volatilized. Atmospheric removal of PBDEs due to processes such as reactions with OH radical and photolysis were studied using a heated small-volume reaction chamber with online detection of reactants and products by mass spectrometry. Relative rate constants for the reaction of OH with 7 diphenyl ethers having 0 to 2 bromine substituents were determined. Photolysis decays measured for selected PBDE congeners in the gas-phase were substantial, indicating that their photolysis quantum yields are significant. Dibenzofuran production was observed when PBDE congeners containing ortho-bromines were photolyzed in helium. From estimates of removal rates of PBDEs from the lower troposphere, we find that wet and dry deposition account for greater than 95% of the removal of BDE-209, while photolysis accounts for about 90% of the removal of gas-phase congeners such as BDE-47. These results help explain the deposition patterns of PBDEs found in lake and river sediments and have important implications concerning the inclusion of photolysis as a fate process in multi-media models. Relative rate constants were also determined for the reaction of OH with acetone and 3

  11. 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.

  12. 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

  13. Monitoring atmospheric pollutants with a heterodyne radiometer transmitter-receiver

    NASA Technical Reports Server (NTRS)

    Menzies, R. T. (Inventor)

    1973-01-01

    The presence of selected atmospheric pollutants can be determined by transmitting an infrared beam of proper wavelength through the atmosphere, and detecting the reflections of the transmitted beam with a heterodyne radiometer transmitter-receiver using part of the laser beam as a local oscillator. The particular pollutant and its absorption line strength to be measured are selected by the laser beam wave length. When the round-trip path for the light is known or measured, concentration can be determined. Since pressure (altitude) will affect the shape of the molecular absorption line of a pollutant, tuning the laser through a range of frequencies, which includes a part of the absorption line of the pollutant of interest, yields pollutant altitude data from which the altitude and altitude profile is determined.

  14. 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

  15. ZASPE: Zonal Atmospheric Stellar Parameters Estimator

    NASA Astrophysics Data System (ADS)

    Brahm, Rafael; Jordan, Andres; Hartman, Joel; Bakos, Gaspar

    2016-07-01

    ZASPE (Zonal Atmospheric Stellar Parameters Estimator) computes the atmospheric stellar parameters (Teff, log(g), [Fe/H] and vsin(i)) from echelle spectra via least squares minimization with a pre-computed library of synthetic spectra. The minimization is performed only in the most sensitive spectral zones to changes in the atmospheric parameters. The uncertainities and covariances computed by ZASPE assume that the principal source of error is the systematic missmatch between the observed spectrum and the sythetic one that produces the best fit. ZASPE requires a grid of synthetic spectra and can use any pre-computed library minor modifications.

  16. 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

  17. Particle Pollution Estimation Based on Image Analysis

    PubMed Central

    Liu, Chenbin; Tsow, Francis; Zou, Yi; Tao, Nongjian

    2016-01-01

    Exposure to fine particles can cause various diseases, and an easily accessible method to monitor the particles can help raise public awareness and reduce harmful exposures. Here we report a method to estimate PM air pollution based on analysis of a large number of outdoor images available for Beijing, Shanghai (China) and Phoenix (US). Six image features were extracted from the images, which were used, together with other relevant data, such as the position of the sun, date, time, geographic information and weather conditions, to predict PM2.5 index. The results demonstrate that the image analysis method provides good prediction of PM2.5 indexes, and different features have different significance levels in the prediction. PMID:26828757

  18. Particle Pollution Estimation Based on Image Analysis.

    PubMed

    Liu, Chenbin; Tsow, Francis; Zou, Yi; Tao, Nongjian

    2016-01-01

    Exposure to fine particles can cause various diseases, and an easily accessible method to monitor the particles can help raise public awareness and reduce harmful exposures. Here we report a method to estimate PM air pollution based on analysis of a large number of outdoor images available for Beijing, Shanghai (China) and Phoenix (US). Six image features were extracted from the images, which were used, together with other relevant data, such as the position of the sun, date, time, geographic information and weather conditions, to predict PM2.5 index. The results demonstrate that the image analysis method provides good prediction of PM2.5 indexes, and different features have different significance levels in the prediction.

  19. Study of atmospheric pollution scavenging. [Annotated bibligraphy

    SciTech Connect

    Williams, A.L.

    1990-08-01

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

  20. The Influence of Meteorological Factors and Atmospheric Pollutants on the Risk of Preterm Birth.

    PubMed

    Giorgis-Allemand, Lise; Pedersen, Marie; Bernard, Claire; Aguilera, Inmaculada; Beelen, Rob M J; Chatzi, Leda; Cirach, Marta; Danileviciute, Asta; Dedele, Audrius; van Eijsden, Manon; Estarlich, Marisa; Fernández-Somoano, Ana; Fernández, Mariana F; Forastiere, Francesco; Gehring, Ulrike; Grazuleviciene, Regina; Gruzieva, Olena; Heude, Barbara; Hoek, Gerard; de Hoogh, Kees; van den Hooven, Edith H; Håberg, Siri E; Iñiguez, Carmen; Jaddoe, Vincent W V; Korek, Michal; Lertxundi, Aitana; Lepeule, Johanna; Nafstad, Per; Nystad, Wenche; Patelarou, Evridiki; Porta, Daniela; Postma, Dirkje; Raaschou-Nielsen, Ole; Rudnai, Peter; Siroux, Valérie; Sunyer, Jordi; Stephanou, Euripides; Sørensen, Mette; Eriksen, Kirsten Thorup; Tuffnell, Derek; Varró, Mihály J; Vrijkotte, Tanja G M; Wijga, Alet; Wright, John; Nieuwenhuijsen, Mark J; Pershagen, Göran; Brunekreef, Bert; Kogevinas, Manolis; Slama, Rémy

    2017-01-13

    Atmospheric pollutants and meteorological conditions are suspected to be causes of preterm birth. We aimed to characterize their possible association with the risk of preterm birth (defined as birth occurring before 37 completed gestational weeks). We pooled individual data from 13 birth cohorts in 11 European countries (71,493 births from the period 1994-2011, European Study of Cohorts for Air Pollution Effects (ESCAPE)). City-specific meteorological data from routine monitors were averaged over time windows spanning from 1 week to the whole pregnancy. Atmospheric pollution measurements (nitrogen oxides and particulate matter) were combined with data from permanent monitors and land-use data into seasonally adjusted land-use regression models. Preterm birth risks associated with air pollution and meteorological factors were estimated using adjusted discrete-time Cox models. The frequency of preterm birth was 5.0%. Preterm birth risk tended to increase with first-trimester average atmospheric pressure (odds ratio per 5-mbar increase = 1.06, 95% confidence interval: 1.01, 1.11), which could not be distinguished from altitude. There was also some evidence of an increase in preterm birth risk with first-trimester average temperature in the -5°C to 15°C range, with a plateau afterwards (spline coding, P = 0.08). No evidence of adverse association with atmospheric pollutants was observed. Our study lends support for an increase in preterm birth risk with atmospheric pressure.

  1. Source estimation methods for atmospheric dispersion

    NASA Astrophysics Data System (ADS)

    Shankar Rao, K.

    Both forward and backward transport modeling methods are being developed for characterization of sources in atmospheric releases of toxic agents. Forward modeling methods, which describe the atmospheric transport from sources to receptors, use forward-running transport and dispersion models or computational fluid dynamics models which are run many times, and the resulting dispersion field is compared to observations from multiple sensors. Forward modeling methods include Bayesian updating and inference schemes using stochastic Monte Carlo or Markov Chain Monte Carlo sampling techniques. Backward or inverse modeling methods use only one model run in the reverse direction from the receptors to estimate the upwind sources. Inverse modeling methods include adjoint and tangent linear models, Kalman filters, and variational data assimilation, among others. This survey paper discusses these source estimation methods and lists the key references. The need for assessing uncertainties in the characterization of sources using atmospheric transport and dispersion models is emphasized.

  2. Estimating the social costs of nitrogen pollution

    NASA Astrophysics Data System (ADS)

    Gourevitch, J.; Keeler, B.; Polasky, S.

    2014-12-01

    Agricultural expansion can degrade water quality and related ecosystem services through increased export of nutrients. Such damages to water quality can negatively affect recreation, property values, and human health. While the relationship between agricultural production and nitrogen export is well-studied, the economic costs of nitrogen loss are less well understood. We present a comprehensive assessment of the full costs associated with nitrate pollution from agricultural sources in Minnesota. We found that the most significant economic costs are likely from groundwater contamination of nitrate in public and private wells. For example, we estimated that loss of grassland to corn cultivation in Minnesota between 2007 and 2012 is expected to increase the future number of domestic wells exceeding nitrate concentrations of 10 ppm by 31%. This increase in contamination is estimated to cost well owners $1.4 to 19 million (present values over a 20 year horizon) through remediation, avoidance, and replacement. Our findings demonstrate linkages between changes in land use, water quality, and human well-being.

  3. 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 -…

  4. 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

  5. Kinetic studies of simulated polluted atmospheres. Final report January 1976-April 1979

    SciTech Connect

    Calvert, J.G.

    1980-01-01

    The kinetics and reaction mechanisms of several important atmospheric contaminants - SO2, formaldehyde, nitrous acid, and the nitrosamines - were assessed to help quantify some key aspects of the chemistry of polluted atmospheres. The reactions and lifetimes of excited sulfur dioxide with various atmospheric components including hydroxyl, hydroperoxy, and methylperoxy radicals were studied. These data and other published rate data were reviewed and evaluated. The photolysis of formaldehyde was investigated as a major source of hydroperoxyl radicals, and a quantitative evaluation made of its apparent first order rate constants at various solar zenith angles. The absolute extinction coefficients for nitrous acid were determined, and estimates made of the rates of hydroxyl radical generation in the troposphere by photolysis of nitrous acid. Long path Fourier transform infrared spectroscopy was used to help evaluate the potential for nitrosamine formation in the polluted atmosphere.

  6. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2008-12-01

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

  8. 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.

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

    PubMed

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

    2015-04-01

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

  10. Estimating Atmospheric Turbulence From Flight Records

    NASA Technical Reports Server (NTRS)

    Wingrove, R. C.; Bach, R. E., Jr.; Schultz, T. A.

    1991-01-01

    Method for estimation of atmospheric turbulence encountered by airplanes utilizes wealth of data captured by multichannel digital flight-data recorders and air-traffic-control radar. Developed as part of continuing effort to understand how airplanes respond to such potentially hazardous phenomena as: clear-air turbulence generated by destabilized wind-shear layers above mountains and thunderstorms, and microbursts (intense downdrafts striking ground), associated with thunderstorms. Reconstructed wind fields used to predict and avoid future hazards.

  11. Modeling pollutant transport in the atmosphere boundary layer

    SciTech Connect

    O`Steen, B.L.

    1990-12-31

    The two basic methods for modeling the atmospheric transport of pollutants (diagnostic and prognostic) are examined along with the current models utilized at SRS for emergency response (WINDS). The ability of a limited-area (mesoscale) model, nested within a synoptic scale model, to represent a wide range of flow behavior, makes it the method of choice for predicting pollutant transport. Such a mesoscale model can provide an invaluable research tool and, with a periodic processing strategy for wind field calculation and/or sufficient computer capability, can be utilized in an emergency response capacity. Various models are compared.

  12. Modeling pollutant transport in the atmosphere boundary layer

    SciTech Connect

    O'Steen, B.L.

    1990-01-01

    The two basic methods for modeling the atmospheric transport of pollutants (diagnostic and prognostic) are examined along with the current models utilized at SRS for emergency response (WINDS). The ability of a limited-area (mesoscale) model, nested within a synoptic scale model, to represent a wide range of flow behavior, makes it the method of choice for predicting pollutant transport. Such a mesoscale model can provide an invaluable research tool and, with a periodic processing strategy for wind field calculation and/or sufficient computer capability, can be utilized in an emergency response capacity. Various models are compared.

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

    NASA Astrophysics Data System (ADS)

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

    2005-06-01

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

  14. [Atmospheric air pollution: a risk factor for COPD?].

    PubMed

    Allain, Y-M; Roche, N; Huchon, G

    2010-04-01

    Tobacco smoking is the leading cause of COPD worldwide but other risk factors have been recognized. Air pollution is one of them, but its exact role in the development of COPD is hard to demonstrate. Its physiological effects on lung function have only been studied since the nineties by long and tedious cohort studies. Difficulties arise from the heterogeneity of air pollution (gas and particles); thus, its respiratory effects have to be examined for every component separately, and in different populations. It is also necessary to analyse the effects of atmospheric pollution in the short and the long term, considering both its physiological, clinical and toxicological effects, from childhood to adulthood. These factors make it difficult to obtain statistically significant results. Nevertheless, most studies seem to point to a role of air pollution in the development of COPD via oxydative stress but further studies are needed to confirm the exact effect of each component of air pollution on the respiratory tract. These studies could lead to improved public health policies and results are awaited that would identify at-risk populations, decide appropriate preventive measures and propose documented thresholds in pollution exposure... thereby limiting the spread of COPD.

  15. 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.

  16. The propagation of light pollution in the atmosphere

    NASA Astrophysics Data System (ADS)

    Cinzano, P.; Falchi, F.

    2012-12-01

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

  17. Long path DOAS measurements of atmospheric pollutants concentration

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

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

  18. Intense winter atmospheric pollution episodes affecting the Western Mediterranean.

    PubMed

    Pey, Jorge; Pérez, Noemí; Querol, Xavier; Alastuey, Andrés; Cusack, Michael; Reche, Cristina

    2010-03-15

    The geographic location of the Western Mediterranean Basin and its peculiar topography, the climatic conditions and the intense anthropogenic and natural emissions of atmospheric pollutants are key factors necessary to interpret the atmospheric aerosol phenomenology over this area. During the cold season it is common to have severe atmospheric particulate matter (PM) pollution episodes (of an anthropogenic origin) affecting this region, not only in the urban and industrial areas but also in the regional and rural sites. During these episodes, the midday hourly PM(1) levels at regional background sites are in many cases higher than those at urban areas. Around 10% of the days under winter anticyclonic conditions registered similar PM(1) levels at the regional background than at the urban area and, sporadically the daily PM(1) levels at the regional background sites may exceed those at urban sites. Furthermore, the very high hourly PM(1) levels measured at regional background sites during these episodes are not regularly attained in the closest urban areas, which leads to the hypothesis that an important formation of secondary aerosols occurs during the transport of the polluted air masses towards the elevated rural sites. The interpretation of the variability of PM levels and composition (2002-2008) at one urban site (Barcelona) and at one regional background site (Montseny) allows us to illustrate the phenomenology of these scenarios, to quantify the mean annual contributions to the PM levels and to identify their main tracers. Ammonium nitrate appears to be the most abundant compound during these scenarios, although organic species and trace metals also increase markedly. Owing to the intensity, composition and recurrence of these atmospheric pollution episodes, important health, climatic and ecological implications may be derived.

  19. Model JC-1 Laser System for Monitoring Atmospheric Pollution,

    DTIC Science & Technology

    2007-11-02

    differential absorption mode atmospheric pollution laser monitoring system, in which a phase locking technique and single board computer are used for...amplification 1 3. synchronous demodulation 2 4. phase locking amplification 2 5. single board computer 6. function logging Instrument 7. oscillator...were then fed into a DBJ-Z80 single - board computer to undergo a multiple averaging process before going through functional operation, and were logged

  20. Magnetic quantification of urban pollution sources in atmospheric particulate matter

    NASA Astrophysics Data System (ADS)

    Spassov, S.; Egli, R.; Heller, F.; Nourgaliev, D. K.; Hannam, J.

    2004-11-01

    A new method is presented for fast quantification of urban pollution sources in atmospheric particulate matter (PM). The remanent magnetization of PM samples collected in Switzerland at sites with different exposures to pollution sources is analysed. The coercivity distribution of each sample is calculated from detailed demagnetization curves of anhysteretic remanent magnetization (ARM) and is modelled using a linear combination of appropriate functions which represent the contribution of different sources of magnetic minerals to the total magnetization. Two magnetic components, C1 and C2, are 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. The same sites were monitored independently by Hüglin using detailed chemical analysis and a quantitative source attribution of the PM. His results are compared with the magnetic component analysis. The absolute and relative magnetic contributions of component C2 correlate very well with absolute and relative mass contributions of exhaust emissions, respectively. Traffic is the most important PM pollution source in Switzerland: it includes exhaust emissions and abrasion products released by vehicle brakes. Component C2 and traffic-related PM sources correlate well, which is encouraging for the implementation of non-destructive magnetic methods as an economic alternative to chemical analysis when mapping urban dust pollution.

  1. 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.

  2. 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.

  3. 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)

  4. Atmospheric deposition exposes Qinling pandas to toxic pollutants.

    PubMed

    Chen, Yi-Ping; Zheng, Ying-Juan; Liu, Qiang; Song, Yi; An, Zhi-Sheng; Ma, Qing-Yi; Ellison, Aaron M

    2016-12-31

    The giant panda (Ailuropoda melanoleuca) is one of the most endangered animals in the world, and it is recognized worldwide as a symbol for conservation. A previous study showed that wild and captive pandas, especially those of the Qinling subspecies, were exposed to toxicants in their diet of bamboo; the ultimate origin of these toxicants is unknown. Here we show that atmospheric deposition is the most likely origin of heavy metals and persistent organic pollutants (POPs) in the diets of captive and wild Qinling pandas. Average atmospheric deposition was 199, 115 and 49 g∙m(-2) ∙yr(-1) in the center of Xi'an city, at China's Shaanxi Wild Animal Research Center (SWARC), and at Foping National Nature Reserve (FNNR), respectively. Atmospheric deposition of heavy metals (As, Cd, Cr, Pb, Hg, Co, Cu, Zn, Mn and Ni) and POPs was highest at Xi'an city, intermediate at SWARC, and lowest at FNNR. Soil concentrations of the aforementioned heavy metals other than As and Zn also were significantly higher at SWARC than at FNNR. Efforts to conserve Qinling pandas may be compromised by air pollution attendant to China's economic development. Improvement of air quality and reductions of toxic emissions are urgently required to protect China's iconic species. This article is protected by copyright. All rights reserved.

  5. Prediction of atmospheric dispersion of pollutants in an airport environment

    NASA Astrophysics Data System (ADS)

    Das, S. K.; Durbin, P. A.

    In this article we discuss the development of a methodology to predict atmospheric turbulent dispersion of pollutants generated from air traffic in an airport. It is based on the Lagrangian stochastic model (LSM), developed by Das and Durbin [2005. A Lagrangian stochastic model for dispersion in stratified turbulence, Physics of Fluids 17, 025109]. The approach is via the backward trajectory formulation of the model. The sources and receptors in an airport type problem are modeled as spheres and procedures have been derived for concentration calculation by both forward and backward trajectory methods. Some tests are performed to highlight certain features of the method. The turbulence statistics that are required as input are provided in terms of similarity profiles. The airport domain is partitioned to make the required search algorithms efficient. Pollutant concentration profiles are calculated over a range of meteorological data.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Health Risk of Exposure to Atmospheric Pollutant Particles

    EPA Science Inventory

    In relation to multi-component mixture nature of atmospheric PM, this presentation will discuss methods for estimating the respiratory internal dose by experiment and mathematical modeling, limitations of each method and interpretations of the results in the context of health ris...

  11. 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.

  12. 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.

  13. Global transport of organic pollutants: ambient concentrations in the remote marine atmosphere.

    PubMed

    Atlas, E; Giam, C S

    1981-01-09

    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.

  14. 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.

  15. Prospects for non-thermal atmospheric plasmas for pollution abatement

    NASA Astrophysics Data System (ADS)

    McAdams, R.

    2001-09-01

    For approximately the past ten years, atmospheric pressure non-thermal plasmas have been increasingly promoted as a technology for a number of applications in the area of pollution abatement. In such plasmas, the electrons have a significantly higher temperature compared to the ions, atoms and molecules. This paper provides an overview of both the technologies involved and the diverse potential application areas. A general description of these atmospheric plasmas and the basic principles involved in the destruction or removal of gaseous phase pollutants, based on the nature of the processes taking place within these plasmas, are given. A number of examples of the different plasma technologies are described. The technologies described are pulsed corona, microwave and dielectric barrier plasmas. Their suitability and use in various application areas are also discussed including incinerator off gas treatment, industrial process off gas treatment and diesel exhaust aftertreatment. The use of modelling of the physical and chemical processes involved to predict system performance and as a tool for sizing systems to meet customer requirements is also discussed.

  16. 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.

  17. Recreational atmospheric pollution episodes: Inhalable metalliferous particles from firework displays

    NASA Astrophysics Data System (ADS)

    Moreno, Teresa; Querol, Xavier; Alastuey, Andrés; Cruz Minguillón, Mari; Pey, Jorge; Rodriguez, Sergio; Vicente Miró, José; Felis, Carles; Gibbons, Wes

    The use of fireworks creates an unusual and distinctive anthropogenic atmospheric pollution event. We report on aerosol samples collected during Las Fallas in Valencia, a 6-day celebration famous for its firework displays, and add comparative data on firework- and bonfire-contaminated atmospheric aerosol samples collected from elsewhere in Spain (Barcelona, L'Alcora, and Borriana) and during the Guy Fawkes celebrations in London. Specific high-profile official firework events during Las Fallas included the afternoon Mascletà and the nightly aerial displays (especially in the climactic final 2 days of the fiesta) and were accompanied by pollution spikes in suspended particles, NO, SO 2, and the creation and dispersal of an aerosol cloud enriched in a range of metallic elements. Notable metal aerosol concentration increases recorded during Las Fallas were potassium (from 500 to 5900 ng m -3), aluminium (as Al 2O 3 from around 600 to 2200 ng m -3), titanium (from 200 to 700 ng m -3), magnesium (from 100 to 500 ng m -3), lead (from 17 to 379 ng m -3), barium (from 39 to 322 ng m -3), strontium (from 3 to 112 ng m -3), copper (from 12 to 71 ng m -3), and antimony (from 1 to 52 ng m -3). Firework-contaminated aerosols of similarly metalliferous composition were also identified at the other monitoring sites, although different sites show variations attributable to other sources such as bonfires and local industry. Unusual levels of the trace elements Ba, Sr and (to a lesser extent) Cu, always in proportions with Ba dominant, along with strongly enhanced K, Pb, and Sb, are identified as being particularly characteristic of firework aerosols. Although firework-related recreational pollution episodes are transient in nature, they are highly concentrated, contribute significantly to total annual metal emissions, and are on average fine enough to be easily inhaled and a health risk to susceptible individuals.

  18. Estimation of microwave absorption in the Jupiter atmosphere

    NASA Technical Reports Server (NTRS)

    Coombs, W. C.

    1971-01-01

    A procedure for estimating the microwave absorption loss of the Jupiter atmosphere is presented. Estimation of microwave absorption by planetary atmospheres involves two different investigative disciplines (1) the determination of an acceptable model of the atmosphere itself and (2) the determination of the microwave attenuation rate applicable to each different volume sample of the atmosphere, and the integration of this loss over the varying radio propagation path for any given entry trajectory to obtain the total loss.

  19. 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.

  20. Estimating atmospheric parameters and reducing noise for multispectral imaging

    DOEpatents

    Conger, James Lynn

    2014-02-25

    A method and system for estimating atmospheric radiance and transmittance. An atmospheric estimation system is divided into a first phase and a second phase. The first phase inputs an observed multispectral image and an initial estimate of the atmospheric radiance and transmittance for each spectral band and calculates the atmospheric radiance and transmittance for each spectral band, which can be used to generate a "corrected" multispectral image that is an estimate of the surface multispectral image. The second phase inputs the observed multispectral image and the surface multispectral image that was generated by the first phase and removes noise from the surface multispectral image by smoothing out change in average deviations of temperatures.

  1. Atmospheric mercury emissions from polluted gold mining areas (Venezuela).

    PubMed

    García-Sánchez, A; Contreras, F; Adams, M; Santos, F

    2006-12-01

    Soil, waste rock and mud from mercury-gold amalgamation mining areas of El Callao (Venezuela) are highly enriched in Hg (0.5-500 microg g(-1)) relative to natural background concentrations (<0.1 microg g(-1)). Mercury fluxes to the atmosphere from twelve polluted sites of this area were measured in situ (6 a.m. to 8 p.m.) using a Plexiglas flux chamber connected to a portable mercury analyzer (model RA-915+; Lumex, St. Petersburg, Russia). Mercury fluxes ranged between 0.65 and 420.1 microg m(-2) h(-1), and the average flux range during the diurnal hours was 9.1-239.2 microg m(-2) h(-1). These flux values are five orders of magnitude higher than both reported world background Hg fluxes (1-69 ng m(-2) h(-1)) and the regional values, which are in the range 2-10 ng m(-2) h(-1). The flux results obtained in this study are, however, similar to those measured at Hg polluted sites such as chloro-alkali plants or polymetallic ore mining districts (>100,000 ng m(-2) h(-1)). The results from this study also show that Hg emissions from the soil are influenced by solar radiation, soil temperature and soil Hg concentration. Our data suggest that solar radiation may be the dominant factor affecting Hg degrees emission since the major species of mercury in polluted soil is Hg degrees (85-97% of total Hg). The simple release of Hg degrees vapor is probably the dominant process occurring with incident light in the field. The apparent activation energy for mercury emission indicates that the volatilization of mercury mainly occurred as a result of the vaporization of elemental mercury in soil. The degree of Hg emission differed significantly among the soil sites studied, which may be due to variations in soil texture, organic matter content and soil compaction.

  2. Atmospheric Concentrations of Persistent Organic Pollutants in the Southern Ocean

    NASA Astrophysics Data System (ADS)

    Vlahos, P.; Edson, J.; Cifuentes, A.; McGillis, W. R.; Zappa, C.

    2008-12-01

    Long-range transport of persistent organic pollutant (POPs) is a global concern. Remote regions such as the Southern Ocean are greatly under-sampled though critical components in understanding POPs cycling. Over 20 high-volume air samples were collected in the Southern Ocean aboard the RV Brown during the GASEX III experiment between Mar 05 to April 9 2008. The relatively stationary platform (51S,38W) enabled the collection of a unique atmospheric time series at this open ocean station. Air sampling was also conducted across transects from Punto Arenas, Chile and to Montevideo, Uruguay. Samples were collected using glass sleeves packed with poly-urethane foam plugs and C-18 resin in order to collect target organic pollutants (per-fluorinated compounds, currently and historically used pesticides) in this under-sampled region. Here we present POPs concentrations and trends over the sampled period and compare variations with air parcel back trajectories to establish potential origins of their long-range transport.

  3. 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.

  4. Laser-excited fluorescence for measuring atmospheric pollution

    NASA Technical Reports Server (NTRS)

    Menzies, R. T.

    1975-01-01

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

  5. 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.

  6. [Atmospheric air pollution in an industrial city as the factor of non-carcinogenic risk for health of communities].

    PubMed

    Surzhikov, V D; Surzhikov, D V; Golikov, R A

    2013-01-01

    The paper deals with the results of the research on risk of exposure of atmospheric air pollution in a large industrial city to health of communities. The results of individual both immediate and chronic risk estimation for selectable city zones are presented. Regression ratios of various substances concentrations and disease incidence are revealed. On their basis the estimation of risk of additional disease incidence is carried out and taxonomic values characterizing the contribution of separate pollutants to risk of health of communities' disorder are obtained.

  7. 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.

  8. Atmospheric visibility estimation and image contrast calibration

    NASA Astrophysics Data System (ADS)

    Hermansson, Patrik; Edstam, Klas

    2016-10-01

    A method, referred to as contrast calibration, has been developed for transforming digital color photos of outdoor scenes from the atmospheric conditions, illumination and visibility, prevailing at the time of capturing the image to a corresponding image for other atmospheric conditions. A photo captured on a hazy day can, for instance, be converted to resemble a photo of the same scene for good visibility conditions. Converting digital color images to specified lightning and transmission conditions is useful for image based assessment of signature suppression solutions. The method uses "calibration objects" which are photographed at about the same time as the scene of interest. The calibration objects, which (indirectly) provide information on visibility and lightning conditions, consist of two flat boards, painted in different grayscale colors, and a commercial, neutral gray, reference card. Atmospheric extinction coefficient and sky intensity can be determined, in three wavelength bands, from image pixel values on the calibration objects and using this information the image can be converted to other atmospheric conditions. The image is transformed in contrast and color. For illustration, contrast calibration is applied to sample images of a scene acquired at different times. It is shown that contrast calibration of the images to the same reference values of extinction coefficient and sky intensity results in images that are more alike than the original images. It is also exemplified how images can be transformed to various other atmospheric weather conditions. Limitations of the method are discussed and possibilities for further development are suggested.

  9. Atmospheric Turbulence Estimates from a Pulsed Lidar

    NASA Technical Reports Server (NTRS)

    Pruis, Matthew J.; Delisi, Donald P.; Ahmad, Nash'at N.; Proctor, Fred H.

    2013-01-01

    Estimates of the eddy dissipation rate (EDR) were obtained from measurements made by a coherent pulsed lidar and compared with estimates from mesoscale model simulations and measurements from an in situ sonic anemometer at the Denver International Airport and with EDR estimates from the last observation time of the trailing vortex pair. The estimates of EDR from the lidar were obtained using two different methodologies. The two methodologies show consistent estimates of the vertical profiles. Comparison of EDR derived from the Weather Research and Forecast (WRF) mesoscale model with the in situ lidar estimates show good agreement during the daytime convective boundary layer, but the WRF simulations tend to overestimate EDR during the nighttime. The EDR estimates from a sonic anemometer located at 7.3 meters above ground level are approximately one order of magnitude greater than both the WRF and lidar estimates - which are from greater heights - during the daytime convective boundary layer and substantially greater during the nighttime stable boundary layer. The consistency of the EDR estimates from different methods suggests a reasonable ability to predict the temporal evolution of a spatially averaged vertical profile of EDR in an airport terminal area using a mesoscale model during the daytime convective boundary layer. In the stable nighttime boundary layer, there may be added value to EDR estimates provided by in situ lidar measurements.

  10. 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.

  11. 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.

  12. Estimating lake-atmosphere CO2 exchange

    USGS Publications Warehouse

    Anderson, D.E.; Striegl, R.G.; Stannard, D.I.; Michmerhuizen, C.M.; McConnaughey, T.A.; LaBaugh, J.W.

    1999-01-01

    Lake-atmosphere CO2 flux was directly measured above a small, woodland lake using the eddy covariance technique and compared with fluxes deduced from changes in measured lake-water CO2 storage and with flux predictions from boundary-layer and surface-renewal models. Over a 3-yr period, lake-atmosphere exchanges of CO2 were measured over 5 weeks in spring, summer, and fall. Observed springtime CO2 efflux was large (2.3-2.7 ??mol m-2 s-1) immediately after lake-thaw. That efflux decreased exponentially with time to less than 0.2 ??mol m-2 s-1 within 2 weeks. Substantial interannual variability was found in the magnitudes of springtime efflux, surface water CO2 concentrations, lake CO2 storage, and meteorological conditions. Summertime measurements show a weak diurnal trend with a small average downward flux (-0.17 ??mol m-2 s-1) to the lake's surface, while late fall flux was trendless and smaller (-0.0021 ??mol m-2 s-1). Large springtime efflux afforded an opportunity to make direct measurement of lake-atmosphere fluxes well above the detection limits of eddy covariance instruments, facilitating the testing of different gas flux methodologies and air-water gas-transfer models. Although there was an overall agreement in fluxes determined by eddy covariance and those calculated from lake-water storage change in CO2, agreement was inconsistent between eddy covariance flux measurements and fluxes predicted by boundary-layer and surface-renewal models. Comparison of measured and modeled transfer velocities for CO2, along with measured and modeled cumulative CO2 flux, indicates that in most instances the surface-renewal model underpredicts actual flux. Greater underestimates were found with comparisons involving homogeneous boundary-layer models. No physical mechanism responsible for the inconsistencies was identified by analyzing coincidentally measured environmental variables.

  13. Improved Estimates of Air Pollutant Emissions from Biorefinery

    SciTech Connect

    Tan, Eric C. D.

    2015-11-13

    We have attempted to use detailed kinetic modeling approach for improved estimation of combustion air pollutant emissions from biorefinery. We have developed a preliminary detailed reaction mechanism for biomass combustion. Lignin is the only biomass component included in the current mechanism and methane is used as the biogas surrogate. The model is capable of predicting the combustion emissions of greenhouse gases (CO2, N2O, CH4) and criteria air pollutants (NO, NO2, CO). The results are yet to be compared with the experimental data. The current model is still in its early stages of development. Given the acknowledged complexity of biomass oxidation, as well as the components in the feed to the combustor, obviously the modeling approach and the chemistry set discussed here may undergo revision, extension, and further validation in the future.

  14. 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

  15. 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

  16. Estimating accidental pollutant releases in the built environment from turbulent concentration signals

    NASA Astrophysics Data System (ADS)

    Ben Salem, N.; Salizzoni, P.; Soulhac, L.

    2017-01-01

    We present an inverse atmospheric model to estimate the mass flow rate of an impulsive source of pollutant, whose position is known, from concentration signals registered at receptors placed downwind of the source. The originality of this study is twofold. Firstly, the inversion is performed using high-frequency fluctuating, i.e. turbulent, concentration signals. Secondly, the inverse algorithm is applied to a dispersion process within a dense urban canopy, at the district scale, and a street network model, SIRANERISK, is adopted. The model, which is tested against wind tunnel experiments, simulates the dispersion of short-duration releases of pollutant in different typologies of idealised urban geometries. Results allow us to discuss the reliability of the inverse model as an operational tool for crisis management and the risk assessments related to the accidental release of toxic and flammable substances.

  17. [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

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

    NASA Technical Reports Server (NTRS)

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

    1980-01-01

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

  19. 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.

  20. Estimates of health risk from exposure to radioactive pollutants

    SciTech Connect

    Sullivan, R.E.; Nelson, N.S.; Ellett, W.H.; Dunning, D.E. Jr.; Leggett, R.W.; Yalcintas, M.G.; Eckerman, K.F.

    1981-11-01

    A dosimetric and health effects analysis has been performed for the Office of Radiation Programs of the Environmental Protection Agency (EPA) to assess potential hazards from radioactive pollutants. Contemporary dosimetric methods were used to obtain estimates of dose rates to reference organs from internal exposures due to either inhalation of contaminated air or ingestion of contaminated food, or from external exposures due to either immersion in contaminated air or proximity to contaminated ground surfaces. These dose rates were then used to estimate the number of premature cancer deaths arising from such exposures and the corresponding number of years of life lost in a cohort of 100,000 persons, all simultaneously liveborn and all going through life with the same risks of dying from competing causes. The risk of dying from a competing cause for a given year was taken to be the probability of dying from all causes as given in a recent actuarial life table for the total US population.

  1. Atmospheric water on Mars, energy estimates for extraction

    NASA Technical Reports Server (NTRS)

    Meyer, Tom

    1991-01-01

    The Mars atmosphere is considered as a resource for water to support a human expedition. Information obtained from the Viking mission is used to estimate the near-surface water vapor level. The variability over the diurnal cycle is examined and periods of greatest water abundance are identified. Various methods for extracting atmospheric water are discussed including energy costs and the means for optimizing water extraction techniques.

  2. [Simulation of air pollution characteristics and estimates of environmental capacity in Zibo City].

    PubMed

    Xue, Wen-Bo; Wang, Jin-Nan; Yang, Jin-Tian; Lei, Yu; Yan, Li; He, Jin-Yu; Han, Bao-Ping

    2013-04-01

    To develop a new pattern of air pollution control that is based on the integration of "concentration control, total amount control, and quality control", and in the context of developing national (2011-2015 air pollution control plan for key areas) and (Environmental protection plan of Zibo municipality for the "12th Five-Year Plan" period), a simulation of atmospheric dispersion of air pollutants in Zibo City and its peripheral areas is carried out by employing CALPUFF model, and the atmospheric environmental capacity of SO2, NO(x) and PM10 is estimated based on the results of model simulation and using multi-objective linear programming optimization. The results indicates that the air pollution in Zibo City is significantly related to the pollution sources outside of Zibo City, which contributes to the annual average concentration of SO2, NO2 and PM10 in Zibo City by 26.34%, 21.23%, and 14.58% respectively. There is a notable interaction between districts and counties of Zibo municipality, in which the contribution of SO2, NO(x) and PM10 emissions in surrounding counties and districts to the annual average concentrations of SO2, NO2 and PM10 in downtown area are 35.96%, 43.17%, and 17.69% respectively. There is a great variation in spatial sensitivity of air pollutant emission, and the environmental impact of unit pollutant emissions from Zhoucun, Huantai, Zhangdian and Zichuan is greater than that released from other districts/counties. To meet the requirement of (Ambient air quality standard) (GB 3095-2012), the environmental capacities of SO2, NO(x) and PM10 of Zibo City are only 8.03 x 10(4) t, 19.16 x 10(4) t and 3.21 x 10(4) t, respectively. Therefore, it is imperative to implement regional air pollution joint control in Shandong peninsula in order to ensure the achievement of air quality standard in Zibo City.

  3. 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

  4. 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.

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

    SciTech Connect

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

    1990-10-01

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

  6. Laser methods for the control of atmospheric gases and gases which pollute the atmosphere

    NASA Astrophysics Data System (ADS)

    Antipov, A. B.; Zuev, V. E.; Kapitanov, V. A.; Lopasov, V. P.; Lukianenko, S. F.; Sinitsa, L. N.; Sapozhnikova, V. A.

    Laser methods for the control of atmospheric pollutants are currently being developed. Laser devices for gas analysis are being designed, taking into account the analytical determination of carbon monoxide, ozone, nitric oxide, and acetylene. The operation of these devices is based on the absorption of radiation, and the wavelength region from 5 to 10 microns is utilized. However, an employment of this spectral region introduces problems in connection with the location of the intense vibrational-rotational absorption spectrum of water vapor and CO2 in this wavelength region. The present investigation is, therefore, concerned with the use of the wavelength region from 0.5 to 3.5 microns as a basis for the design of suitable laser devices for analytical applications. An optoacoustic method is considered along with an 'intracavity absorption' method discussed by Belikova et al. (1972). A description is presented of the results obtained in measurements conducted with laser spectrometers. Performance data concerning a number of developed laser spectrometers are also provided.

  7. Atmospheric chemistry: Scientific basis for sound health-protective and cost-effective air pollution control strategies

    SciTech Connect

    Pitts, J.N. Jr.

    1995-12-01

    The validity of risk assessments for airborne toxics, and the effectiveness of associated risk management decisions, clearly depend on the accuracy of the data bases employed to estimate human and/or ecosystem exposures. Three current examples are used to illustrate the necessity of including in today`s risk assessments not only total emissions and ambient levels of specific primary pollutants, but also their reaction products: (1) indoor NO{sub 2} and gaseous HONO; (2) conversion of {open_quotes}non-toxic{close_quotes} polycyclic aromatic hydrocarbons to powerful bacterial mutagens; and (3) the conversion in polluted air of a {open_quotes}safe{close_quotes} pesticide, used to eradicate a major agricultural threat, to a more toxic compound to which hundreds of thousands of Southern Californians have been exposed. The pressing need for fundamental research on the atmospheric chemistry of such diverse classes of pollutants and the health effects of their reaction products is discussed.

  8. Adjoint modeling for atmospheric pollution process sensitivity at regional scale

    NASA Astrophysics Data System (ADS)

    Menut, Laurent

    2003-09-01

    During the summer 1998, a strong pollution event was documented over Paris as part of the Etude et Simulation de la Qualité de l'air en Ile-de-France (ESQUIF) project (second intensive observation period (IOP2)). From 7 to 9 August 1998 the pollution event changes from a well-marked ozone plume issued from Paris to a more general pollution over the whole Ile-de-France region. Using a three-dimensional chemistry-transport model and its adjoint part, the sensitivity of ozone, Ox, and NOx peaks to model parameters is investigated. For two locations, Paris and a suburban site, the influence of both meteorological and chemical model parameters on the simulated field concentrations is hourly quantified for each day. Processes leading to a urban polluted event are compared. It is shown that the pollutant concentrations are mainly driven by traffic and solvent surface emissions and meteorological parameters such as temperature. Since the adjoint approach is limited to infinitesimal model perturbation, some scenario simulations are carried out to evaluate the linearity of the impact of the most sensitive parameters within the uncertainty range. It is shown that the sensitivities determined from the adjoint approach can be extrapolated until their uncertainty ranges except for the wind speed.

  9. Estimate of mercury emissions to the atmosphere from petroleum.

    PubMed

    Wilhelm, S M

    2001-12-15

    An estimate of the contribution of mercury to the atmospheric environment from petroleum processed in the United States is constructed from recent data. The estimate is based on a mass balance approach for mercury in crude oil, in refined products, and in waste streams (air, water, solid waste) from refineries. Although there are insufficient data at present to have a high degree of confidence in the mean amount and range of mercury concentrations in crude oil or in refined products, the framework of the estimate should assist direction for the acquisition of additional data. On the basis of selected data that put the estimated mean concentration of total mercury in crude oil close to 10 ppb, it is calculated that the total amount of mercury in U.S. petroleum processed yearly is slightly over 8000 kg/yr. Of this amount, approximately 6000 kg/yr is estimated to be emitted to the atmosphere from combustion of liquid hydrocarbon fuels, which represents about 10% of the U.S. yearly emission rate of atmospheric mercury from coal combustion. The material balance predicts that the amount of mercury in air emissions from all U.S. refineries is on the order of 1500 kg/yr based on the assumption that fugitive mercury emissions from refineries are negligible. Atmospheric emissions of mercury from fuel oil burned in the United States are estimated in the U.S. EPA Mercury Report to Congress to be approximately 10000 kg/yr, and this estimate may be in error on the high side by a factor of 3-10. If the mean amounts of mercury in U.S. distillate and residual fuel oils are in the range of 5-15 ppb, as suggested by more recent data, then U.S. fuel oil combustion should contribute no more that about 1000-3000 kg/yr (emission ratio = 1) of mercury to the atmospheric burden.

  10. Alternative normalization method of atmospheric polycyclic aromatic hydrocarbons pollution level recorded by tree bark.

    PubMed

    Zhao, Yuli; Wang, Qiuquan; Yang, Limin; Li, Zhenji; Satake, Kenichi; Tsunoda, Kin-Ichi

    2006-10-01

    An alternative normalization method was developed for evaluating atmospheric polycyclic aromatic hydrocarbons (PAHs) pollution level when using tree bark as a passive sampling medium. Perylene (PER), which mainly stems from natural biogenic processes, was proposed as a "natural internal compound" (NIC) of atmospheric PAHs accumulation processes from air into the bark, and a concentration ratio of target PAH to PER (RPAH/PER) was used to minimize the uncertainty in the evaluation of atmospheric PAHs pollution level. Systematic investigation of the effects of intrinsic bark characteristics and extrinsic seasonal meteorological conditions on the partition processes of atmospheric PAHs indicated that RPAH/PER is as an alternative index as compared to bark mass concentration (BMCPAH, ng/g dry bark), lipid mass concentration (LMCPAH, ng/g lipid of bark), and area mass concentration (AMCPAH, ng/m2 surface area of bark) for the evaluation of atmospheric PAHs pollution and that it allows more flexible sampling of tree barks. Clearly, the methodology should be expected to be useful for the objective evaluation of atmospheric pollution levels of other persistent organic pollutants when using tree bark and other passive sampling media if corresponding NICs are found in the future.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. [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.

  16. The apparatus-program system for remote detection and analysis of pollution in the atmosphere

    NASA Astrophysics Data System (ADS)

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

    2006-02-01

    The apparatus-program system DAN-2 developed for registration of emission and absorption of optical and microwave radiation initiated by gas-aerosol pollution in the atmosphere is presented. In the DAN-2, the problem of automation of recording processes, storage and processing of the information measured in experiment has been solved. Algorithms of the techniques incorporated in subsystems of the program complex for calculation and estimation of atmospheric anomalies include: - calculation of gas concentration in a plume of industrial emission taking into account gas-aerosol attenuation, an azimuth of the device sighting to a direction on the source and the allocated illumination of the day-time sky; - numerical modeling of formation and distribution of gas-aerosol emission fields in the atmosphere with use of various models (Gaussian, Berlyand, etc.); - the forecast of optical noise in the atmosphere taking into account different types of underground surfaces under various meteorological conditions; - the restoration algorithm of the plume structure using its image. Application of a modular principle has created an opportunity to realize all subsystems independently from each other 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.

  17. 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.

  18. 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.

  19. Improving estimates of air pollution exposure through ubiquitous sensing technologies

    PubMed Central

    de Nazelle, Audrey; Seto, Edmund; Donaire-Gonzalez, David; Mendez, Michelle; Matamala, Jaume; Nieuwenhuijsen, Mark J; Jerrett, Michael

    2013-01-01

    Traditional methods of exposure assessment in epidemiological studies often fail to integrate important information on activity patterns, which may lead to bias, loss of statistical power or both in health effects estimates. Novel sensing technologies integrated with mobile phones offer potential to reduce exposure measurement error. We sought to demonstrate the usability and relevance of the CalFit smartphone technology to track person-level time, geographic location, and physical activity patterns for improved air pollution exposure assessment. We deployed CalFit-equipped smartphones in a free living-population of 36 subjects in Barcelona, Spain. Information obtained on physical activity and geographic location was linked to space-time air pollution mapping. For instance, we found on average travel activities accounted for 6% of people’s time and 24% of their daily inhaled NO2. Due to the large number of mobile phone users, this technology potentially provides an unobtrusive means of collecting epidemiologic exposure data at low cost. PMID:23416743

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

    SciTech Connect

    Lucie Erbanova; Martin Novak; Daniela Fottova; Barbora Dousova

    2008-10-01

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

  1. Range estimation of passive infrared targets through the atmosphere

    NASA Astrophysics Data System (ADS)

    Cho, Hoonkyung; Chun, Joohwan; Seo, Doochun; Choi, Seokweon

    2013-04-01

    Target range estimation is traditionally based on radar and active sonar systems in modern combat systems. However, jamming signals tremendously degrade the performance of such active sensor devices. We introduce a simple target range estimation method and the fundamental limits of the proposed method based on the atmosphere propagation model. Since passive infrared (IR) sensors measure IR signals radiating from objects in different wavelengths, this method has robustness against electromagnetic jamming. The measured target radiance of each wavelength at the IR sensor depends on the emissive properties of target material and various attenuation factors (i.e., the distance between sensor and target and atmosphere environment parameters). MODTRAN is a tool that models atmospheric propagation of electromagnetic radiation. Based on the results from MODTRAN and atmosphere propagation-based modeling, the target range can be estimated. To analyze the proposed method's performance statistically, we use maximum likelihood estimation (MLE) and evaluate the Cramer-Rao lower bound (CRLB) via the probability density function of measured radiance. We also compare CRLB and the variance of MLE using Monte-Carlo simulation.

  2. 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.

  3. 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

  4. 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.

  5. Estimation of Atmospheric Mixing Layer Height from radiosonde data

    NASA Astrophysics Data System (ADS)

    Wang, X.; Wang, K.

    2013-12-01

    Mixing layer is the lowest layer of the troposphere where surface turbulence can reach during the daytime. Mixing layer height (MLH) is an important parameter for understanding the transport process, air pollution, weather and climate change. MLH can be determined from the radiosonde profiles of relative humidity (RH), specific humidity (q), potential temperature (θ) and atmospheric refractivity (N) by searching for the strongest gradients of these parameters within a specific height above the surface. However, substantially different MLHs have been found from different parameters. The occurrence of cloud impacts on MLHs derived in two ways: (1) clouds impact the measurements of θ and RH, resulting in spurious MLHs derived by θ and RH, (2) clouds may amplify or depress turbulence, that is MLH can be at cloud top or cloud base when it occurs. However, MLHs determined by existing methods can generally be at cloud top. To solve these problems, we propose a method to estimate MLH by integrating the information of θ, RH, q, N and discriminating different cloud impacts on MLH. We apply this method to high vertical resolution (~30 m) radiosonde data collected at the 79 stations over North America during the period of 1998 to 2008 released by the Stratospheric Processes and their Role in Climate Data Center. The results show good agreement with those from N as the information of temperature and humidity contained in N, however the impact of clouds including in the new method has increased the reliability of MLH. The new results show good agreement with independent MLH determined from Lidar observations. MLH over the North America is 1647×323 meter with a strong east-west gradient, higher MLH (generally greater than 1800 m) over the Midwest America and lower MLH (less than 1300 m) over Alaska and west coast of America. The scatter plot of climatological MLHnew with MLHθ, MLHRH, MLHq, MLHN and MLHint for the period of 1998 to 2008. Pattern of climatological MLH of our

  6. 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…

  7. Planetary Probe Entry Atmosphere Estimation Using Synthetic Air Data System

    NASA Technical Reports Server (NTRS)

    Karlgaard, Chris; Schoenenberger, Mark

    2017-01-01

    This paper develops an atmospheric state estimator based on inertial acceleration and angular rate measurements combined with an assumed vehicle aerodynamic model. The approach utilizes the full navigation state of the vehicle (position, velocity, and attitude) to recast the vehicle aerodynamic model to be a function solely of the atmospheric state (density, pressure, and winds). Force and moment measurements are based on vehicle sensed accelerations and angular rates. These measurements are combined with an aerodynamic model and a Kalman-Schmidt filter to estimate the atmospheric conditions. The new method is applied to data from the Mars Science Laboratory mission, which landed the Curiosity rover on the surface of Mars in August 2012. The results of the new estimation algorithm are compared with results from a Flush Air Data Sensing algorithm based on onboard pressure measurements on the vehicle forebody. The comparison indicates that the new proposed estimation method provides estimates consistent with the air data measurements, without the use of pressure measurements. Implications for future missions such as the Mars 2020 entry capsule are described.

  8. 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.

  9. Atmospheric Effects on Winter SO2 Pollution in Lanzhou China

    DTIC Science & Technology

    2008-01-01

    in Lanzhou (APCL), supported jointly by Gansu Province and the Chinese Academy of Sciences and carried out from 1999 to 2001. In this study, the...jointly by Gansu Province and the Chinese Academy of Sciences and carried out from 1999 to 2001. From the APCL project, the air quality data were...are provided by the program entitled “Air Pollution and Control in Lanzhou” jointly sponsored by the local government of Gansu Province and the

  10. Properties of nitrate, sulfate and ammonium in typical polluted atmospheric aerosols (PM 10) in Beijing

    NASA Astrophysics Data System (ADS)

    Kai, Zhang; Yuesi, Wang; Tianxue, Wen; Yousef, Meslmani; Frank, Murray

    2007-03-01

    To gain an understanding of the characteristics of nitrate, sulfate and ammonium in the urban atmosphere of Beijing, an experiment was conducted in October 2004, using a method involving the rapid collection of particles and analysis using an ion chromatography system. The study shows that the mean concentration of water soluble ions (WSI) increased during heavily polluted weather, and this change in the concentration of pollutants was related to the meteorological background. The concentration of nitrate, sulfate and ammonium increased 7.9, 4.1 and 5.4 times, respectively, during heavily polluted periods. The concentration of nitrate increased most among the WSI in PM 10. The diurnal variations of nitrate, sulfate and ammonium in more polluted periods were different from those in less polluted periods. The highest concentration of nitrate (NO 3-), sulfate (SO 42-), and ammonium (NH 4+) appeared at 19:00 during more polluted periods. In contrast, the highest concentrations of these compounds occurred at noon during less polluted periods. A correlation analysis showed that NO 3-, SO 42-, NH 4+, nitrogen oxides (NO x) and sulfur dioxide (SO 2) had significant positive correlations in more polluted periods. The transformation ratio from SO 2 and NO x to SO 42- and NO 3- was higher in more polluted than that in less polluted periods.

  11. [Quantitative estimation source of urban atmospheric CO2 by carbon isotope composition].

    PubMed

    Liu, Wei; Wei, Nan-Nan; Wang, Guang-Hua; Yao, Jian; Zeng, You-Shi; Fan, Xue-Bo; Geng, Yan-Hong; Li, Yan

    2012-04-01

    To effectively reduce urban carbon emissions and verify the effectiveness of currently project for urban carbon emission reduction, quantitative estimation sources of urban atmospheric CO2 correctly is necessary. Since little fractionation of carbon isotope exists in the transportation from pollution sources to the receptor, the carbon isotope composition can be used for source apportionment. In the present study, a method was established to quantitatively estimate the source of urban atmospheric CO2 by the carbon isotope composition. Both diurnal and height variations of concentrations of CO2 derived from biomass, vehicle exhaust and coal burning were further determined for atmospheric CO2 in Jiading district of Shanghai. Biomass-derived CO2 accounts for the largest portion of atmospheric CO2. The concentrations of CO2 derived from the coal burning are larger in the night-time (00:00, 04:00 and 20:00) than in the daytime (08:00, 12:00 and 16:00), and increase with the increase of height. Those derived from the vehicle exhaust decrease with the height increase. The diurnal and height variations of sources reflect the emission and transport characteristics of atmospheric CO2 in Jiading district of Shanghai.

  12. 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.

  13. Biologic Effects of Atmospheric Pollutants: Asbestos - The Need For and Feasibility of Air Pollution Controls

    EPA Pesticide Factsheets

    This 1971 report sets forth in a well-organized fashion the currently available information on asbestos as an air pollutant, with special attention to sources health effects, measurements, and feasibility of control.

  14. Contribution of atmospheric emissions to the contamination of leaf vegetables by persistent organic pollutants (POPs): Application to Southeastern France

    NASA Astrophysics Data System (ADS)

    Quéguiner, Solen; Musson Genon, Luc; Roustan, Yelva; Ciffroy, Philippe

    2010-03-01

    A modeling approach has been developed to estimate the contribution of atmospheric emissions to the contamination of leaf vegetables by persistent organic pollutants (POPs). It combines an Eulerian chemical transport model for atmospheric processes (Polair3D/Polyphemus) with a fate and transport model for soil and vegetation (Ourson). These two models were specifically adapted for POPs. Results are presented for benzo(a)pyrene (BaP). As expected no accumulation of BaP in leaf vegetables appears during the growth period for each harvest over the 10 years simulated. For BaP and leaf vegetables, this contamination depends primarily on direct atmospheric deposition without chemical transfer from the soil to the plant. These modeling results are compared to available data.

  15. Transboundary Atmospheric Pollution of Oil-Gas Industry Emissions from North Caspian region of Kazakhstan

    NASA Astrophysics Data System (ADS)

    Zakarin, E.; Balakay, L.; Mirkarimova, B.; Mahura, A.; Baklanov, A.; Sorensen, J. H.

    2012-04-01

    The Atyraus region (Republic of Kazahstan) is occupied with more than 60 oil-gas fields which are actively developing. Moreover, a new world largest field so-called Kashagan has been discovered on the Caspian Sea shelf and its exploitation is planned by the end of 2012. In our study, this region has been selected as a source region of sulphates emissions accounting about 15 tons (2009 estimates). Three locations have been chosen in the region covering adjacent Caspian Sea aquatoria, and emissions were equally distributed among these locations (with an emission rate of 4.72*10-4 kg/sec). From original sulphates emissions between 46-82% are subjected to atmospheric transport away from the sources. Releases were considered to be continuous. The long-term modelling of atmospheric transport, dispersion and deposition of sulphates was done employing the Lagrangian type model called DERMA, run at the NEC SX6 supercomputing facilities. After each day of release the atmospheric transport has been tracked for the next 2 week period. Input meteorological 3D fields were obtained from the ECMWF data archives. The generated output included air concentration (at model levels), time integrated air concentration, dry and wet deposition (at the surface). The results of dispersion modelling had been post-processed and integrated into GIS environment (using ArcGIS). These have been further used to calculate annual averaged and summary concentration and deposition fields for administrative regions, counties and cities of Kazakhstan, as well as territories of the neighboring countries. It has been found that on an annual scale, the dominating atmospheric transport of pollution from the Atyraus region is toward east and north-east, mostly due to prevailing westerlies. Although on a hemispheric scale, the wet deposition dominates over dry (63 vs. 37%), for Kazakhstan the wet deposition contribution is slightly larger (65%). For Turkmenistan, dry deposition is almost twice higher compared

  16. 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.

  17. [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.

  18. 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.

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

    NASA Technical Reports Server (NTRS)

    Tiwari, S. N.

    1973-01-01

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

  20. An objective definition of air mass types affecting Athens, Greece; the corresponding atmospheric pressure patterns and air pollution levels.

    PubMed

    Sindosi, O A; Katsoulis, B D; Bartzokas, A

    2003-08-01

    This work aims at defining characteristic air mass types that dominate in the region of Athens, Greece during the cold (November-March) and the warm (May-September) period of the year and also at evaluating the corresponding concentration levels of the main air pollutants. For each air mass type, the mean atmospheric pressure distribution (composite maps) over Europe and the Mediterranean is estimated in order to reveal the association of atmospheric circulation with air pollution levels in Athens. The data basis for this work consists of daily values of thirteen meteorological and six pollutant parameters covering the period 1993-97. The definition of the characteristic air mass types is attempted objectively by using the methods of Factor Analysis and Cluster Analysis. The results show that during the cold period of the year there are six prevailing air mass types (at least 3% of the total number of days) and six infrequent ones. The examination of the corresponding air pollution concentration levels shows that the primary air pollutants appear with increased concentrations when light or southerly winds prevail. This is usually the case when a high pressure system is located over the central Mediterranean or a low pressure system lays over south Italy, respectively. Low levels of the primary pollutants are recorded under northeasterly winds, mainly caused by a high pressure system over Ukraine. During the warm period of the year, the southwestern Asia thermal low and the subtropical anticyclone of the Atlantic Ocean affect Greece. Though these synoptic systems cause almost stagnant conditions, four main air mass types are dominant and ten others, associated with extreme weather, are infrequent. Despite the large amounts of total solar radiation characterizing this period, ozone concentrations remain at low levels in central Athens because of its destruction by nitric oxide.

  1. 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.

  2. 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.

  3. Millimeter and submillimeter wave absorption by atmospheric pollutants and constituents

    NASA Astrophysics Data System (ADS)

    Kolbe, W. F.; Leskovar, B.

    1981-10-01

    Calculated absorption coefficients and rotational transition frequencies are given for a number of polar molecules of interest to pollution and energy research. The results, which are presented in graphical form for microwave frequencies up to 1400 GHz, illustrate the increased absorption line intensities occurring in the submillimeter region. For most species these absorption coefficients attain their maximum values in this region. Included in the calculations are the gases SO2, H2CO, O3, H2O, H2S, OCS, CO, NO, OH, SO, NH3, and CS. A discussion of the techniques currently available for the detection in the submillimeter region of these species is also given.

  4. 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.

  5. Geostatistical model to estimate in stream pollutant loads and concentrations.

    NASA Astrophysics Data System (ADS)

    Polus, E.; Flipo, N.; de Fouquet, C.; Poulin, M.

    2009-04-01

    Models that estimate loads and concentrations of pollutants in streams can roughly be classified into two categories: physically-based and stochastic models. While the first ones tend to reproduce physical processes that occur in streams, the stochastic models consider loads and concentrations as random variables. This work is interesting in such models and particularly in geostatistical models, which provide an estimate of loads and concentrations and the joint measurement of uncertainty also: the estimation variance. Along a stream network that can be modelled as a graph, most of usual geostatistical covariance or variogram models are not valid anymore. Based on recent models applied on tree graphs, we present a covariance or variogram construction combining one-dimensional Random Functions (RF) defined on each path between sources and the outlet. The model properties are examined, namely the consistency conditions at the confluences for different variables. In practice, the scarcity of spatial data makes a precise inference of covariances difficult. Can then a phenomenological model be used to guide the geostatistical modelling? To answer this question the example of a portion of the Seine River (France) is examined, where both measurement data and the outputs of the physically-based model ProSe are used. The comparison between both data sets shows an excellent agreement for discharges and a consistent one for nitrate concentrations. Nevertheless, a detailed exploratory analysis brings to light the importance of the boundary conditions, which ones are not consistent with the downstream measurements. The agreement between data and modelled values can be improved thanks to a reconstruction of consistent boundary conditions by cokriging. This is an example of the usefulness of using jointly physically-based models and geostatistics. The next step is a joint modelling of discharges, loads and concentrations along the stream network. This modelling should improve the

  6. 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

  7. Silica nanoparticles capture atmospheric lead: implications in the treatment of environmental heavy metal pollution.

    PubMed

    Yang, Xifei; Shen, Zhiguo; Zhang, Bing; Yang, Jianping; Hong, Wen-Xu; Zhuang, Zhixiong; Liu, Jianjun

    2013-01-01

    Lead (Pb) contamination in the air is a severe global problem, most notably in China. Removal of Pb from polluted air remains a significant challenge. It is unclear what potential effects silica nanoparticles (SiNPs) exposure can have on atmospheric Pb. Here we first characterized the features of SiNPs by measuring the particle size, zeta potential and the specific surface area of SiO(2) particles using a Nicomp 380/ZLS submicron particle sizer, the Brunauer-Emmett-Teller (BET) method and transmission electronic microscopy (TEM). We measured the content of the metal Pb adsorbed by SiNPs exposed to two Pb polluted electric battery plants using inductively coupled plasma mass spectrometry (ICP-MS). It is found that SiNPs exposed to two Pb polluted electric battery plants absorb more atmospheric Pb compared to either blank control or micro-sized SiO(2) particles in a time-dependent manner. This is the first study demonstrating that SiNPs exposure can absorb atmospheric Pb in the polluted environment. These novel findings indicate that SiNPs have potential to serve as a significant adsorbent of Pb from industrial pollution, implicating a potentially novel application of SiNPs in the treatment of environmental heavy metal pollution.

  8. Application of cascade lasers to detection of trace gaseous atmospheric pollutants

    NASA Astrophysics Data System (ADS)

    Miczuga, Marcin; Kopczyński, Krzysztof

    2016-12-01

    Understanding the impact of gaseous pollutants on the earth's atmosphere, as well as more and more felt by mankind negative effects of its contamination, result in increasing the level of environmental awareness and contribute to the intensification of actions aimed at reducing the emission of harmful gases into the atmosphere. At the same time, the extensive studies are conducted in order to continuously monitor the level of air contamination with harmful gases and the industry compliance with the standards limited the amount of emitted pollutants. Over recent years, there has been increasing use of cascade lasers and multi-pass cells in optical systems detecting the gaseous atmospheric pollutants and measuring the gas concentrations. The paper presents the use of a tunable quantum cascade laser as a source of the IR radiation in an advanced detection system enabling the trace gaseous atmospheric pollutants to be identified. Apart from the laser, the main elements of the system are: a multi-pass cell, an IR detector and a module for control and analysis. Operation of the system is exemplified by measuring the level of the air pollution with ammonia, carbon oxide and nitrous oxide.

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

    SciTech Connect

    Williams, A.L.

    1990-08-01

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

  11. Study on polarization features of carbonaceous particles in atmosphere pollutants

    NASA Astrophysics Data System (ADS)

    Li, Da; Zeng, Nan; Wang, Yunfei; Chen, Dongsheng; Chen, Yuerong; Ma, Hui

    2016-09-01

    The carbonaceous particles are the main source of the light absorption in atmospheric aerosol. Different from the case in tissue-like turbid media, the light absorption in atmospheric environments can be described as an inherent attribute on scatterers rather than an interstitial propagation effect. In this paper, we simulated the optical absorption due to carbonaceous scatterers and analyzed the influence of various parameters on their polarization properties, such as the imaginary part refractive index, the size and shape. Also we compare these results with our previous research work on absorption effect in ambient medium. For the single scattering, the polarization scattering angular distribution implies the potential of distinguishing different carbonaceous particles with different structural and absorption parameters. In the other hand, for the week scattering case of suspension system, using the backward Mueller matrix polar decomposition method, we can find out that the additional absorption effect on carbonaceous particles can enhance their depolarization and moreover produce more diattenuation and linear retardance for those anisotropic particles. The subsequent experiments of standard samples show a good agreement with simulation results. The paper further studies the phase function of single scattering and the distribution of scattering numbers, which can explain these unique polarization scattering phenomena. We hope these fundamental results can help to investigate how to identify the carbonaceous particles and characterize their optical features from the atmospheric hybrid suspension system.

  12. Estimation of atmospheric parameters from time-lapse imagery

    NASA Astrophysics Data System (ADS)

    McCrae, Jack E.; Basu, Santasri; Fiorino, Steven T.

    2016-05-01

    A time-lapse imaging experiment was conducted to estimate various atmospheric parameters for the imaging path. Atmospheric turbulence caused frame-to-frame shifts of the entire image as well as parts of the image. The statistics of these shifts encode information about the turbulence strength (as characterized by Cn2, the refractive index structure function constant) along the optical path. The shift variance observed is simply proportional to the variance of the tilt of the optical field averaged over the area being tracked. By presuming this turbulence follows the Kolmogorov spectrum, weighting functions can be derived which relate the turbulence strength along the path to the shifts measured. These weighting functions peak at the camera and fall to zero at the object. The larger the area observed, the more quickly the weighting function decays. One parameter we would like to estimate is r0 (the Fried parameter, or atmospheric coherence diameter.) The weighting functions derived for pixel sized or larger parts of the image all fall faster than the weighting function appropriate for estimating the spherical wave r0. If we presume Cn2 is constant along the path, then an estimate for r0 can be obtained for each area tracked, but since the weighting function for r0 differs substantially from that for every realizable tracked area, it can be expected this approach would yield a poor estimator. Instead, the weighting functions for a number of different patch sizes can be combined through the Moore-Penrose pseudo-inverse to create a new weighting function which yields the least-squares optimal linear combination of measurements for estimation of r0. This approach is carried out, and it is observed that this approach is somewhat noisy because the pseudo-inverse assigns weights much greater than one to many of the observations.

  13. Combined methodology for estimating dose rates and health effects from exposure to radioactive pollutants

    SciTech Connect

    Dunning, D.E. Jr.; Leggett, R.W.; Yalcintas, M.G.

    1980-12-01

    The work described in the report is basically a synthesis of two previously existing computer codes: INREM II, developed at the Oak Ridge National Laboratory (ORNL); and CAIRD, developed by the Environmental Protection Agency (EPA). The INREM II code uses contemporary dosimetric methods to estimate doses to specified reference organs due to inhalation or ingestion of a radionuclide. The CAIRD code employs actuarial life tables to account for competing risks in estimating numbers of health effects resulting from exposure of a cohort to some incremental risk. The combined computer code, referred to as RADRISK, estimates numbers of health effects in a hypothetical cohort of 100,000 persons due to continuous lifetime inhalation or ingestion of a radionuclide. Also briefly discussed in this report is a method of estimating numbers of health effects in a hypothetical cohort due to continuous lifetime exposure to external radiation. This method employs the CAIRD methodology together with dose conversion factors generated by the computer code DOSFACTER, developed at ORNL; these dose conversion factors are used to estimate dose rates to persons due to radionuclides in the air or on the ground surface. The combination of the life table and dosimetric guidelines for the release of radioactive pollutants to the atmosphere, as required by the Clean Air Act Amendments of 1977.

  14. Precipitation scavenging of gaseous pollutants having arbitrary solubility in inhomogeneous atmosphere

    NASA Astrophysics Data System (ADS)

    Elperin, Tov; Fominykh, Andrew; Krasovitov, Boris

    2015-04-01

    We investigate scavenging of gaseous pollutants in the atmosphere under the combined influence of rain and varying temperature distribution that affects the rate of soluble gas scavenging. We employ a one-dimensional model of precipitation scavenging of gaseous pollutants having arbitrary solubility that is valid for small gradients and for non-uniform initial vertical distributions of temperature and soluble trace gases concentration in the atmosphere. It is showed that transient altitudinal distributions of temperature and concentration under the influence of rain are determined by linear wave equations that describe propagation of temperature and scavenging wave fronts. Scavenging coefficient and the rates of precipitation scavenging are calculated for wet removal of methanol () using measured initial distribution of methanol and temperature in the atmosphere. Theoretical predictions of the dependence of the magnitude of the scavenging coefficient on rain intensity for tritium oxide and sulfur dioxide are in good agreement with the available atmospheric measurements.

  15. [Automatic Measurement of the Stellar Atmospheric Parameters Based Mass Estimation].

    PubMed

    Tu, Liang-ping; Wei, Hui-ming; Luo, A-li; Zhao, Yong-heng

    2015-11-01

    We have collected massive stellar spectral data in recent years, which leads to the research on the automatic measurement of stellar atmospheric physical parameters (effective temperature Teff, surface gravity log g and metallic abundance [Fe/ H]) become an important issue. To study the automatic measurement of these three parameters has important significance for some scientific problems, such as the evolution of the universe and so on. But the research of this problem is not very widely, some of the current methods are not able to estimate the values of the stellar atmospheric physical parameters completely and accurately. So in this paper, an automatic method to predict stellar atmospheric parameters based on mass estimation was presented, which can achieve the prediction of stellar effective temperature Teff, surface gravity log g and metallic abundance [Fe/H]. This method has small amount of computation and fast training speed. The main idea of this method is that firstly it need us to build some mass distributions, secondly the original spectral data was mapped into the mass space and then to predict the stellar parameter with the support vector regression (SVR) in the mass space. we choose the stellar spectral data from the United States SDSS-DR8 for the training and testing. We also compared the predicted results of this method with the SSPP and achieve higher accuracy. The predicted results are more stable and the experimental results show that the method is feasible and can predict the stellar atmospheric physical parameters effectively.

  16. Atmospheric Sulfur Hexafluoride: Measurements and Emission Estimates from 1970 - 2008

    NASA Astrophysics Data System (ADS)

    Rigby, M. L.; Prinn, R. G.; Muhle, J.; Miller, B. R.; Dlugokencky, E. J.; Krummel, P. B.; Steele, L. P.; Fraser, P. J.; Leist, M.; Weiss, R. F.; Harth, C. M.; O'Doherty, S. J.; Greally, B. R.; Simmonds, P. G.; Derek, N.; Vollmer, M. K.; Kim, J.; Kim, K.; Porter, L. W.

    2009-12-01

    We present an air history of atmospheric sulfur hexafluoride (SF6) from the early 1970s through 2008. During this period, concentrations of this extremely potent and long-lived greenhouse gas have increased by more than an order of magnitude, and its growth has accelerated in recent years. In this study, historical concentrations are determined from archived air samples measured on the Advanced Global Atmospheric Gases Experiment (AGAGE) ‘Medusa’ gas chromatography/mass spectrometry system. These data are combined with modern high-frequency measurements from the AGAGE and National Oceanic and Atmospheric Administration (NOAA) in situ networks and ˜weekly samples from the NOAA flask network, to produce a unique time series with increasing global coverage spanning almost four decades. Using the three-dimensional chemical transport Model for Ozone and Related Tracers (MOZART v4.5) and a discrete Kalman filter, we derive estimates of the annual emission strength of SF6 on hemispheric scales from 1970 - 2004 and on continental scales from 2004 - 2008. Our emission estimates are compared to the recently compiled Emissions Database for Global Atmospheric Research (EDGAR v4), and emissions reported under the United Nations Framework Convention on Climate Change (UNFCCC). The cause of the recent growth rate increase is also investigated, indicating that the origin of the required emissions rise is likely to be South-East Asia.

  17. Millimeter and submillimeter wave absorption by atmospheric pollutants and constituents

    SciTech Connect

    Kolbe, W.F.; Leskovar, B.

    1981-10-01

    Calculated absorption coefficients and rotational transition frequencies are given for a number of polar molecules of interest to pollution and energy research. The results, which are presented in graphical form for microwave frequencies up to 1400 GHz, illustrate the increased absorption line intensities occurring in the submillimeter region. For most species these absorption coefficients attain their maximum values in this region. Included in the calculations are the gases SO/sub 2/, H/sub 2/CO, O/sub 3/, H/sub 2/O, H/sub 2/S, OCS, CO, NO, OH, SO, NH/sub 3/, and CS. A discussion of the techniques currently available for the detection in the submillimeter region of these species is also given.

  18. [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

  19. Atmospheric Inverse Estimates of Methane Emissions from Central California

    SciTech Connect

    Zhao, Chuanfeng; Andrews, Arlyn E.; Bianco, Laura; Eluszkiewicz, Janusz; Hirsch, Adam; MacDonald, Clinton; Nehrkorn, Thomas; Fischer, Marc L.

    2008-11-21

    Methane mixing ratios measured at a tall-tower are compared to model predictions to estimate surface emissions of CH{sub 4} in Central California for October-December 2007 using an inverse technique. Predicted CH{sub 4} mixing ratios are calculated based on spatially resolved a priori CH{sub 4} emissions and simulated atmospheric trajectories. The atmospheric trajectories, along with surface footprints, are computed using the Weather Research and Forecast (WRF) coupled to the Stochastic Time-Inverted Lagrangian Transport (STILT) model. An uncertainty analysis is performed to provide quantitative uncertainties in estimated CH{sub 4} emissions. Three inverse model estimates of CH{sub 4} emissions are reported. First, linear regressions of modeled and measured CH{sub 4} mixing ratios obtain slopes of 0.73 {+-} 0.11 and 1.09 {+-} 0.14 using California specific and Edgar 3.2 emission maps respectively, suggesting that actual CH{sub 4} emissions were about 37 {+-} 21% higher than California specific inventory estimates. Second, a Bayesian 'source' analysis suggests that livestock emissions are 63 {+-} 22% higher than the a priori estimates. Third, a Bayesian 'region' analysis is carried out for CH{sub 4} emissions from 13 sub-regions, which shows that inventory CH{sub 4} emissions from the Central Valley are underestimated and uncertainties in CH{sub 4} emissions are reduced for sub-regions near the tower site, yielding best estimates of flux from those regions consistent with 'source' analysis results. The uncertainty reductions for regions near the tower indicate that a regional network of measurements will be necessary to provide accurate estimates of surface CH{sub 4} emissions for multiple regions.

  20. 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.

  1. Pollutant discharges to coastal areas: Improving upstream source estimates. Final report

    SciTech Connect

    Rohmann, S.O.

    1989-10-01

    The report describes a project NOAA's Strategic Environmental Assessments Division began to improve the estimates of pollutant discharges carried into coastal areas by rivers and streams. These estimates, termed discharges from upstream sources, take into account all pollution discharged by industries, sewage treatment plants, farms, cities, and other pollution-generating operations, as well as natural phenomena such as erosion and weathering which occur inland or upstream of the coastal US.

  2. 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.

  3. Effect of Atmospheric Pollutants on the Air Quality in Tunisia

    PubMed Central

    Bouchlaghem, Karim; Nsom, Blaise

    2012-01-01

    This paper presents the evolution of Saharan dust advection when the PM10 (particles with an aerodynamic diameter below 10 μm) concentration exceeds standard limits in different Tunisian sites. Meteorological and concentration data (from 2004 to 2010) obtained from several monitoring stations and in situ measurements were used to identify African dust change in seasonal occurrence, their source origin, and their impact on surface PM10 concentrations. We pointed out that the Saharan dust contribution caused frequently the surpassing of the maximum number of days in excess of EU standard limits as well as of the maximum yearly average in the Mediterranean Tunisian coasts. The maximum daily concentration reaches 439 μg/m3 during the Saharan events. The decrease in particulate levels recorded at the end of each event is due to the injection of European air masses and rainfalls. Primary pollutants peaks were much higher in winter than in summer which can be explained on the basis of the lower ventilation and mixing. PMID:22654641

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

    NASA Technical Reports Server (NTRS)

    Shumate, M. S.

    1974-01-01

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

  5. 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...

  6. 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.

  7. Methods of valuing air pollution and estimated monetary values of air pollutants in various U.S. regions

    SciTech Connect

    Wang, M.Q.; Santini, D.J.; Warinner, S.A.

    1994-12-01

    Air pollutant emission values are used to determine the social costs of various technologies that cause air pollution and to estimate the benefits of emission control technologies. In this report, the authors present two methods of estimating air pollutant emission values--the damage value method and the control cost method--and review 15 recent studies in which these methods were employed to estimate emission values. The reviewed studies derived emission values for only a limited number of areas; emission value estimates are needed for other US regions. Using the emission values estimated in the reviewed studies, they establish regression relationships between emission values, air pollutant concentrations, and total population exposed, and apply the established relationships to 17 US metropolitan areas to estimate damage-based and control-cost-based emission values for reactive organic gases, nitrogen oxides, particulate matter measuring less than 10 microns, sulfur oxides, and carbon monoxide in these areas. Their estimates show significant variations in emission values across the 17 regions.

  8. 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.

  9. 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.

  10. Air pollution forecasting in Ankara, Turkey using air pollution index and its relation to assimilative capacity of the atmosphere.

    PubMed

    Genc, D Deniz; Yesilyurt, Canan; Tuncel, Gurdal

    2010-07-01

    Spatial and temporal variations in concentrations of CO, NO, NO(2), SO(2), and PM(10), measured between 1999 and 2000, at traffic-impacted and residential stations in Ankara were investigated. Air quality in residential areas was found to be influenced by traffic activities in the city. Pollutant ratios were proven to be reliable tracers to differentiate between different sources. Air pollution index (API) of the whole city was calculated to evaluate the level of air quality in Ankara. Multiple linear regression model was developed for forecasting API in Ankara. The correlation coefficients were found to be 0.79 and 0.63 for different time periods. The assimilative capacity of Ankara atmosphere was calculated in terms of ventilation coefficient (VC). The relation between API and VC was investigated and found that the air quality in Ankara was determined by meteorology rather than emissions.

  11. Characterization, parameter estimation, and aircraft response statistics of atmospheric turbulence

    NASA Technical Reports Server (NTRS)

    Mark, W. D.

    1981-01-01

    A nonGaussian three component model of atmospheric turbulence is postulated that accounts for readily observable features of turbulence velocity records, their autocorrelation functions, and their spectra. Methods for computing probability density functions and mean exceedance rates of a generic aircraft response variable are developed using nonGaussian turbulence characterizations readily extracted from velocity recordings. A maximum likelihood method is developed for optimal estimation of the integral scale and intensity of records possessing von Karman transverse of longitudinal spectra. Formulas for the variances of such parameter estimates are developed. The maximum likelihood and least-square approaches are combined to yield a method for estimating the autocorrelation function parameters of a two component model for turbulence.

  12. Novel Approaches for Estimating Human Exposure to Air Pollutants

    EPA Science Inventory

    Numerous health studies have used measurements from a few central-site ambient monitors to characterize air pollution exposures. Relying on solely on central-site ambient monitors does not account for the spatial-heterogeneity of ambient air pollution patterns, the temporal varia...

  13. Evaluating the effects of China's pollution controls on inter-annual trends and uncertainties of atmospheric mercury emissions

    NASA Astrophysics Data System (ADS)

    Zhao, Y.; Zhong, H.; Zhang, J.; Nielsen, C. P.

    2015-04-01

    China's anthropogenic emissions of atmospheric mercury (Hg) are effectively constrained by national air pollution control and energy efficiency policies. In this study, improved methods, based on available data from domestic field measurements, are developed to quantify the benefits of Hg abatement by various emission control measures. Those measures include increased use of (1) flue gas desulfurization (FGD) and selective catalyst reduction (SCR) systems in power generation; (2) precalciner kilns with fabric filters (FF) in cement production; (3) mechanized coking ovens with electrostatic precipitators (ESP) in iron and steel production; and (4) advanced production technologies in nonferrous metal smelting. Investigation reveals declining trends in emission factors for each of these sources, which together drive a much slower growth of total Hg emissions than the growth of China's energy consumption and economy, from 679 metric tons (t) in 2005 to 750 t in 2012. In particular, estimated emissions from the above-mentioned four source types declined 3% from 2005 to 2012, which can be attributed to expanded deployment of technologies with higher energy efficiencies and air pollutant removal rates. Emissions from other anthropogenic sources are estimated to increase by 22% during the period. The species shares of total Hg emissions have been stable in recent years, with mass fractions of around 55, 39, and 6% for gaseous elemental Hg (Hg0), reactive gaseous mercury (Hg2+), and particle-bound mercury (Hgp), respectively. The higher estimate of total Hg emissions than previous inventories is supported by limited simulation of atmospheric chemistry and transport. With improved implementation of emission controls and energy saving, a 23% reduction in annual Hg emissions from 2012 to 2030, to below 600 t, is expected at the most. While growth in Hg emissions has been gradually constrained, uncertainties quantified by Monte Carlo simulation for recent years have increased

  14. Solar Radiation Estimated Through Mesoscale Atmospheric Modeling over Northeast Brazil

    NASA Astrophysics Data System (ADS)

    de Menezes Neto, Otacilio Leandro; Costa, Alexandre Araújo; Ramalho, Fernando Pinto; de Maria, Paulo Henrique Santiago

    2009-03-01

    The use of renewable energy sources, like solar, wind and biomass is rapidly increasing in recent years, with solar radiation as a particularly abundant energy source over Northeast Brazil. A proper quantitative knowledge of the incoming solar radiation is of great importance for energy planning in Brazil, serving as basis for developing future projects of photovoltaic power plants and solar energy exploitation. This work presents a methodology for mapping the incoming solar radiation at ground level for Northeast Brazil, using a mesoscale atmospheric model (Regional Atmospheric Modeling System—RAMS), calibrated and validated using data from the network of automatic surface stations from the State Foundation for Meteorology and Water Resources from Ceará (Fundação Cearense de Meteorologia e Recursos Hídricos- FUNCEME). The results showed that the model exhibits systematic errors, overestimating surface radiation, but that, after the proper statistical corrections, using a relationship between the model-predicted cloud fraction, the ground-level observed solar radiation and the incoming solar radiation estimated at the top of the atmosphere, a correlation of 0.92 with a confidence interval of 13.5 W/m2 is found for monthly data. Using this methodology, we found an estimate for annual average incoming solar radiation over Ceará of 215 W/m2 (maximum in October: 260 W/m2).

  15. Historical reconstruction of atmospheric lead pollution in central Yunnan province, southwest China: an analysis based on lacustrine sedimentary records.

    PubMed

    Liu, Enfeng; Zhang, Enlou; Li, Kai; Nath, Bibhash; Li, Yanling; Shen, Ji

    2013-12-01

    Atmospheric lead (Pb) pollution during the last century in central Yunnan province, one of the largest non-ferrous metal production centers in China, was reconstructed using sediment cores collected from Fuxian and Qingshui Lakes. Lead concentrations and isotopic ratios ((207)Pb/(206)Pb and (208)Pb/(206)Pb) were measured in sediment cores from both lakes. The operationally defined chemical fractions of Pb in sediment core from Fuxian Lake were determined by the optimized BCR procedure. The chronology of the cores was reconstructed using (210)Pb and (137)Cs dating methods. Similar three-phase variations in isotopic ratios and enrichment factors of Pb were observed in the sediment cores from both lakes. Before the 1950s, the sediment data showed low (207)Pb/(206)Pb and (208)Pb/(206)Pb ratios and enrichment factors (EFs=~1), indicating that the sedimentary Pb was predominantly of lithogenic origin. However, these indices were increased gradually between the 1950s and the mid-1980s, implying an atmospheric Pb deposition. The EFs and isotopic ratios of Pb reached their peak during recent years, indicating aggravating atmospheric Pb pollution. The average anthropogenic Pb fluxes since the mid-1980s were estimated to be 0.032 and 0.053 g m(-2) year(-1) recorded in Fuxian and Qingshui cores, respectively. The anthropogenic Pb was primarily concentrated in the reducible fraction. Combining the results of Pb isotopic compositions and chemical speciations in the sediment cores and in potential sources, we deduced that recent aggravating atmospheric Pb pollution in central Yunnan province should primarily be attributed to regional emissions from non-ferrous metal production industries.

  16. Estimation of biomass burning influence on air pollution around Beijing from an aerosol retrieval model.

    PubMed

    Mukai, Sonoyo; Yasumoto, Masayoshi; Nakata, Makiko

    2014-01-01

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

  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. 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.

  19. 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.

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

    NASA Astrophysics Data System (ADS)

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

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-12-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-11-01

    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.

  3. Foliar Uptake of Atmospheric Reactive Nitrogen Pollution Along an Urban-Rural Gradient in New York State

    NASA Astrophysics Data System (ADS)

    Vallano, D.; Sparks, J. P.

    2008-12-01

    Vegetation is an important sink for atmospheric reactive nitrogen (N) pollution in terrestrial ecosystems, and when soil N is limiting, foliar N uptake can be a source of plant-available N. A proxy for pollution derived N, and in particular foliar assimilated N, would be useful to quantify the impact of the foliar uptake pathway on plant metabolism. Nitrogen stable isotope ratios (15N/14N) are practical for this purpose because forms of plant-available N often have varying isotopic compositions. However, the mechanisms driving differences in foliar N isotopic composition (δ15N) are still unresolved. Current understanding of foliar δ 15N suggests these values primarily represent the integration of the soil water solution δ15N, direct foliar uptake of atmospheric reactive N, within-plant fractionations, and fractionation due to the fungus to root transfer in mycorrhizae. In this study, we investigated the influence of direct foliar uptake, soil solution δ 15N, and mycorrhizae on foliar δ15N in seedlings of two dominant Northeastern tree species, red maple (Acer rubrum) and red oak (Quercus rubra), along an N deposition gradient in New York State. Using a potted plant mesocosm system, we compared foliar δ15N values directly to soil solution δ15N values while controlling for mycorrhizal associations. Both species showed higher foliar δ15N when exposed to fractionation by mycorrhizal associations. Overall, A. rubrum showed higher foliar δ15N than Q. rubra across all sites. In both species, patterns of foliar δ15N values were coupled with soil solution δ15N values across the N deposition gradient. Additionally, increasing atmospheric N deposition was correlated with higher foliar δ15N values in Q. rubra, but not in A. rubrum. Using a mixing model, we estimated that Q. rubra seedlings incorporated up to 7% of their assimilated N via direct foliar uptake of atmospheric N pollution. However, foliar uptake was not detectable in A. rubrum seedlings. Results

  4. Radioactive Pollution Estimate for Fukushima Nuclear Power Plant by a Particle Model

    NASA Astrophysics Data System (ADS)

    Saito, Keisuke; Ogawa, Susumu

    2016-06-01

    On Mar 12, 2011, very wide radioactive pollution occurred by a hydrogen explosion in Fukushima Nuclear Power Plant. A large amount of radioisotopes started with four times of explosions. With traditional atmospheric diffusion models could not reconstruct radioactive pollution in Fukushima. Then, with a particle model, this accident was reconstructed from meteorological archive and Radar- AMeDAS. Calculations with the particle model were carried out for Mar 12, 15, 18 and 20 when east southeast winds blew for five hours continuously. Meteorological archive is expressed by wind speeds and directions in five-km grid every hour with eight classes of height till 3000 m. Radar- AMeDAS is precipitation data in one-km grid every thirty minutes. Particles are ten scales of 0.01 to 0.1 mm in diameter with specific weight of 2.65 and vertical speeds given by Stokes equation. But, on Mar 15, it rained from 16:30 and then the particles fell down at a moment as wet deposit in calculation. On the other hand, the altitudes on the ground were given by DEM with 1 km-grid. The spatial dose by emitted radioisotopes was referred to the observation data at monitoring posts of Tokyo Electric Power Company. The falling points of radioisotopes were expressed on the map using the particle model. As a result, the same distributions were obtained as the surface spatial dose of radioisotopes in aero-monitoring by Ministry of Education, Culture, Sports, Science and Technology. Especially, on Mar 15, the simulated pollution fitted to the observation, which extended to the northwest of Fukushima Daiichi Nuclear Power Plant and caused mainly sever pollution. By the particle model, the falling positions on the ground were estimated each particle size. Particles with more than 0.05 mm of size were affected by the topography and blocked by the mountains with the altitudes of more than 700 m. The particle model does not include the atmospheric stability, the source height, and deposit speeds. The

  5. 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

  6. Atmospheric processes of organic pollutants over a remote lake on the central Tibetan Plateau: implications for regional cycling

    NASA Astrophysics Data System (ADS)

    Ren, Jiao; Wang, Xiaoping; Wang, Chuanfei; Gong, Ping; Yao, Tandong

    2017-01-01

    Atmospheric processes (air-surface exchange, and atmospheric deposition and degradation) are crucial for understanding the global cycling and fate of organic pollutants (OPs). However, such assessments over the Tibetan Plateau (TP) remain uncertain. More than 50 % of Chinese lakes are located on the TP, which exerts a remarkable influence on the regional water, energy, and chemical cycling. In this study, air and water samples were simultaneously collected in Nam Co, a large lake on the TP, to test whether the lake is a secondary source or sink of OPs. Lower concentrations of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were observed in the atmosphere and lake water of Nam Co, while the levels of polycyclic aromatic hydrocarbons (PAHs) were relatively higher. Results of fugacity ratios and chiral signatures both suggest that the lake acted as the net sink of atmospheric hexachlorocyclohexanes (HCHs), following their long-range transport driven by the Indian monsoon. Different behaviours were observed in the PAHs, which primarily originated from local biomass burning. Acenaphthylene, acenaphthene, and fluorene showed volatilization from the lake to the atmosphere, while other PAHs were deposited into the lake due to the integrated deposition process (wet/dry and air-water gas deposition) and limited atmospheric degradation. As the dominant PAH compound, phenanthrene exhibited a seasonal reversal of air-water gas exchange, which was likely related to the melting of the lake ice in May. The annual input of HCHs from the air to the entire lake area (2015 km2) was estimated as 1.9 kg yr-1, while input estimated for 15PAHs can potentially reach up to 550 kg yr-1. This study highlights the significance of PAH deposition on the regional carbon cycling in the oligotrophic lakes of the TP.

  7. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2014-05-01

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

  9. Effect of atmospheric pollution on Vitis vinifera L. pollen ultrastructure under natural conditions

    SciTech Connect

    Stirban, M.; Craciun, C.; Bathory, D.; Cipleu, D.

    1984-06-01

    The ultrastructural modification of pollen grains in Vitis vinifera L. variety and hybrids in areas of SO atmospheric pollution (the main polluting SO2 usually reaches 2.72 mg/m3), nitrogen oxide, and other gases derived from noniron metal processing factories have been studied. Strains 1001 and 1002, resistant varieties, do not undergo ultrastructural modifications. Neuburger and Issabelle, medium resistant ones, have a heterogeneity in ultrastructural organization from normal forms to forms having both wall covers as well as the main organelles changed.

  10. A Direct Estimate of Climate Sensitivity from Atmospheric Structure

    NASA Astrophysics Data System (ADS)

    Lacis, A. A.

    2014-12-01

    The nominal equilibrium climate sensitivity of about 3°C for doubled CO2 is obtained from direct climate model calculations and from simulations of the historical surface temperature record. A similar value of equilibrium climate sensitivity has been inferred from the geological ice core record. A further independent estimate of climate sensitivity can be derived directly from the atmospheric temperature, cloud, and absorbing gas structure. Attribution of individual contributions to the terrestrial greenhouse effect by individual atmospheric constituents shows that water vapor and clouds account for about 75% of the total greenhouse effect, while CO2 and the other minor non-condensing green house gases account for the remaining 25%. It is generally understood that water vapor and cloud contributions to the greenhouse effect arise as feedback effects, and that the non-condensing greenhouse gas contribution can be identified as the radiative forcing component. From this alone, a climate feedback sensitivity of f = 4, or about 5°C for doubled CO2 can be inferred. Accounting further for the negative temperature lapse rate feedback that is not directly included in the attribution analysis, and allowing for a residual non-condensing component of the water vapor feedback, brings the equilibrium climate sensitivity that is inferred from atmospheric structural analysis to the 3°C range for doubled CO2, in good agreement with the equilibrium climate sensitivity that is obtained from comparisons to historical and geological global temperature changes.

  11. High Black Carbon Concentrations and Atmospheric Pollution Around Indian Coal Fired Thermal Power Plants

    NASA Astrophysics Data System (ADS)

    Singh, R. P.; Singh, A. K.; Kumar, S.; Takemura, T.

    2013-12-01

    Emissions from coal-fired Thermal Power Plants (TPPs) are among major sources of black carbon (BC) aerosols in the atmosphere and air quality degradation. Knowledge of BC emissions from TPPs is important in characterizing regional carbonaceous particulate emissions, associated with regional climate forcing as well as effects on human health. Furthermore, elevated BC concentrations, over the Indo-Gangetic Plains (IGP) and the Himalayan foothills, has emerged as an important subject to estimate effects of deposition and atmospheric warming of BC on the accelerated melting of snow and glaciers in the Himalaya. For the first time, this study reports BC concentrations and aerosol characterization near coal-fired power plants in the IGP. Coal-fired TPPs are also recognized as major point-sources of other atmospheric pollutants such as high NO2 hotspots in the IGP, as evident from the OMI Aura satellite observations. In-situ measurements were carried out in Kanpur (central IGP) and Singrauli (eastern IGP), during January and March 2013. We show detailed spatial variability of BC within ~10 km from TPPs, that indicate BC variations up to 95 μg/m3, with strong diurnal variations associated with BC concentration peaks during early morning and evening hours. BC concentrations were measured to be significantly higher in close proximity to the coal-fired TPPs (as high as 200μg/m3), compared to the outside domain of our study region. Co-located ground-based sunphotometer measurements of aerosols also show significant spatial variability around the TPPs, with aerosol optical depth (AOD) in the range 0.38-0.58, and the largest AOD of 0.7 - 0.95 near the TPPs (similar to the peak BC concentrations). Additionally, the Angstrom Exponent was found to be in the range 0.4 - 1.0 (maximum in the morning time) and highest in the vicinity of TPPs (~1.0) suggesting abundance of fine particulates, whereas lowest recorded over the surrounding coal mining fields. We also inter-compare global

  12. Uncertainties associated with parameter estimation in atmospheric infrasound arrays

    NASA Astrophysics Data System (ADS)

    Szuberla, Curt A. L.; Olson, John V.

    2004-01-01

    This study describes a method for determining the statistical confidence in estimates of direction-of-arrival and trace velocity stemming from signals present in atmospheric infrasound data. It is assumed that the signal source is far enough removed from the infrasound sensor array that a plane-wave approximation holds, and that multipath and multiple source effects are not present. Propagation path and medium inhomogeneities are assumed not to be known at the time of signal detection, but the ensemble of time delays of signal arrivals between array sensor pairs is estimable and corrupted by uncorrelated Gaussian noise. The method results in a set of practical uncertainties that lend themselves to a geometric interpretation. Although quite general, this method is intended for use by analysts interpreting data from atmospheric acoustic arrays, or those interested in designing and deploying them. The method is applied to infrasound arrays typical of those deployed as a part of the International Monitoring System of the Comprehensive Nuclear-Test-Ban Treaty Organization.

  13. Estimating Longwave Atmospheric Emissivity in the Canadian Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Ebrahimi, S.; Marshall, S. J.

    2014-12-01

    Incoming longwave radiation is an important source of energy contributing to snow and glacier melt. However, estimating the incoming longwave radiation from the atmosphere is challenging due to the highly varying conditions of the atmosphere, especially cloudiness. We analyze the performance of some existing models included a physically-based clear-sky model by Brutsaert (1987) and two different empirical models for all-sky conditions (Lhomme and others, 2007; Herrero and Polo, 2012) at Haig Glacier in the Canadian Rocky Mountains. Models are based on relations between readily observed near-surface meteorological data, including temperature, vapor pressure, relative humidity, and estimates of shortwave radiation transmissivity (i.e., clear-sky or cloud-cover indices). This class of models generally requires solar radiation data in order to obtain a proxy for cloud conditions. This is not always available for distributed models of glacier melt, and can have high spatial variations in regions of complex topography, which likely do not reflect the more homogeneous atmospheric longwave emissions. We therefore test longwave radiation parameterizations as a function of near-surface humidity and temperature variables, based on automatic weather station data (half-hourly and mean daily values) from 2004 to 2012. Results from comparative analysis of different incoming longwave radiation parameterizations showed that the locally-calibrated model based on relative humidity and vapour pressure performs better than other published models. Performance is degraded but still better than standard cloud-index based models when we transfer the model to another site, roughly 900 km away, Kwadacha Glacier in the northern Canadian Rockies.

  14. Nitrogen trifluoride global emissions estimated from updated atmospheric measurements

    PubMed Central

    Arnold, Tim; Harth, Christina M.; Mühle, Jens; Manning, Alistair J.; Salameh, Peter K.; Kim, Jooil; Ivy, Diane J.; Steele, L. Paul; Petrenko, Vasilii V.; Severinghaus, Jeffrey P.; Baggenstos, Daniel; Weiss, Ray F.

    2013-01-01

    Nitrogen trifluoride (NF3) has potential to make a growing contribution to the Earth’s radiative budget; however, our understanding of its atmospheric burden and emission rates has been limited. Based on a revision of our previous calibration and using an expanded set of atmospheric measurements together with an atmospheric model and inverse method, we estimate that the global emissions of NF3 in 2011 were 1.18 ± 0.21 Gg⋅y−1, or ∼20 Tg CO2-eq⋅y−1 (carbon dioxide equivalent emissions based on a 100-y global warming potential of 16,600 for NF3). The 2011 global mean tropospheric dry air mole fraction was 0.86 ± 0.04 parts per trillion, resulting from an average emissions growth rate of 0.09 Gg⋅y−2 over the prior decade. In terms of CO2 equivalents, current NF3 emissions represent between 17% and 36% of the emissions of other long-lived fluorinated compounds from electronics manufacture. We also estimate that the emissions benefit of using NF3 over hexafluoroethane (C2F6) in electronics manufacture is significant—emissions of between 53 and 220 Tg CO2-eq⋅y−1 were avoided during 2011. Despite these savings, total NF3 emissions, currently ∼10% of production, are still significantly larger than expected assuming global implementation of ideal industrial practices. As such, there is a continuing need for improvements in NF3 emissions reduction strategies to keep pace with its increasing use and to slow its rising contribution to anthropogenic climate forcing. PMID:23341630

  15. Human health risk assessment of lead pollution in atmospheric deposition in Baoshan District, Shanghai.

    PubMed

    Chen, Yuanyuan; Wang, Jun; Shi, Guitao; Sun, Xiaojing; Chen, Zhenlou; Xu, Shiyuan

    2011-12-01

    The lead (Pb) content in atmospheric deposition was determined at 42 sampling sites in Baoshan District of Shanghai, China. Based on exposure and dose-response assessments, the health risk caused by Pb exposure in atmospheric deposition was investigated. The results indicated that Pb was significantly accumulated in atmospheric deposition. The spatial distribution of Pb was mapped by geostatistical analysis, and the results showed that pollution hotspots were present at traffic and industrial zones. Ingestion was the main route of Pb exposure in both adults and children. For children the risk value was above 1, whereas it was below 1 for the adult group. Therefore, children belong to the high-risk group for Pb exposure from atmospheric deposition in the observed area of Shanghai, China.

  16. 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.

  17. Environmental impact of a cadmium atmospheric pollution at Marseille (South France)

    NASA Astrophysics Data System (ADS)

    Noack, Y.; Lefloch, M.; Robin, D.

    2003-05-01

    In 1999, a cadmium atmospheric pollution had been detected at Marseille, south France. Cadmium was emitted by a wire-drawing factory. The Cd atmospheric concentration reached 5000 ng/m^3, 1000 times over the EEC limit value. After the factory closing, cadmium concentration decreased and reached the EEC limit value (5 ng/m^3) one year after. Soils were also polluted by cadmium (to 60 mg/kg). More than fifty percent of the cadmium in soils is contained in the leachable and bioavailable fractions. Concentration in vegetables had also exceeded the authorized values. A study of cadmium concentration in urines of children and adults living around the factory show a higher average concentration for the population (children and adults) in the contaminated zone, compared to a similar population in a non contaminated zone.

  18. 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…

  19. 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…

  20. 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

  1. Evaluating the suitability of different environmental samples for tracing atmospheric pollution in industrial areas.

    PubMed

    Francová, Anna; Chrastný, Vladislav; Šillerová, Hana; Vítková, Martina; Kocourková, Jana; Komárek, Michael

    2017-01-01

    Samples of lichens, snow and particulate matter (PM10, 24 h) are used for the source identification of air pollution in the heavily industrialized region of Ostrava, Upper Silesia, Czech Republic. An integrated approach that uses different environmental samples for metal concentration and Pb isotope analyses was applied. The broad range of isotope ratios in the samples indicates a combination of different pollution sources, the strongest among them being the metallurgical industry, bituminous coal combustion and traffic. Snow samples are proven as the most relevant indicator for tracing metal(loid)s and recent local contamination in the atmosphere. Lichens can be successfully used as tracers of the long-term activity of local and remote sources of contamination. The combination of PM10 with snow can provide very useful information for evaluation of current pollution sources.

  2. Atmospheric pollution: a case study of degrading urban air quality over Punjab, India.

    PubMed

    Sehra, Parmjit Singh

    2007-01-01

    This paper presents the results of a case study of urban air quality over a densely populated city Ludhiana situated in Punjab, India, in the form of monthly and annual average concentrations of Suspended Particulate Matter (SPM), NO2 and SO2 for the periods 1988-1989, 1994-1999 and 2001-2005 which is generally found to be increasing with time and thus requires immediate corrective measures lest the situation becomes totally uncontrollable. The present situation is as bad as in other metropolitan Indian cities, although it seems to have somewhat improved as indicated by the latest 2001-2005 data in comparison with the past 1988-1989 and 1994-1999 data, but much more still needs to be done. In addition to the industrial and vehicular pollution, the agricultural pollution due to the burning of wheat and rice straws by the farmers should also be checked because it also creates tremendous pollution in the atmosphere.

  3. The corrosion of weathering steel by SO2 polluted atmospheres at its very early stages

    NASA Astrophysics Data System (ADS)

    Marco, J. F.; Dávalos, J.; Gracia, M.; Gancedo, J. R.

    1990-07-01

    CEMS was used in conjunction with AES to study the protective film formed on a weathering steel by exposure to a highly SO2-polluted atmosphere. Ferrous species (sulphite) and ferric oxyhydroxides (ferrihydrite and α-FeOOH) were identified as corrosion products. From the correlation of CEMS and AES results the evolution with time of the different compounds is obtained, and a possible reaction sequence is outlined.

  4. [Pollution Level and Source Apportionment of Atmospheric Particles PM₂.₅ in Southwest Suburb of Chengdu in Spring].

    PubMed

    Lin, Yu; Ye, Zhi-xiang; Yang, Huai-jin; Zhang, Ju; Yin, Wei-wen; Li, Xiao-fen

    2016-05-15

    In order to understand the characteristics of PM₂.₅ pollution in the atmosphere of Chengdu southwest suburb, PM₂.₅ particles in Chengdu southwest suburb were collected and analyzed from March 18 to March 31st, 2015. The results showed that the daily average concentration of PM₂.₅ in the southwest suburb of Chengdu reached 121.21 µg · m⁻³, and the average daily concentration of 24 samples in 31 PM₂.₅ samples was over 75 µg · m⁻³, the daily excessive rate was 77%, indicating the PM₂.₅ pollution in the study area was serious in March. When studying the relationship between atmospheric and meteorological factors, it was found that there was a significant index correlation between PM₂.₅ concentration and atmospheric visibility, and it had a positive correlation with temperature and humidity, but the correlation was not obvious. NH₄⁺ (16.24%), SO₄²- (12.58%) and NO₃⁻ (9.91%) were dominant in PM₂.₅ The ratio of NO₃⁻/SO₄²⁻ was 0.77, which indicated that the pollution of stationary sources in the southwest suburb was more severe than that of mobile sources. Organic carbon (OC)/elemental carbon (EC) ratios were higher than 2, which indicated the existence of second organic carbon (SOC). Using OC/EC ratio method to estimate the concentration of SOC, it was found that the average concentration of SOC in the southwest suburb of Chengdu in March was 3.49 µ · m⁻³, and the contribution rate of OC was 20.6%, which showed that the main source of OC in the southwest suburb of Chengdu was primary discharge. The correlation analysis of OC and EC showed that the correlation coefficient reached 0.95, indicating that the OC and EC sources were similar and relatively stable, and there was a great impact of local source emissions on Chengdu southwest suburb in spring, and primary discharge played a dominant role, while the contribution of SOC to OC was relatively small, which was consistent with the SOC characteristics obtained

  5. Sequential optimal monitoring network design and iterative spatial estimation of pollutant concentration for identification of unknown groundwater pollution source locations.

    PubMed

    Prakash, Om; Datta, Bithin

    2013-07-01

    One of the difficulties in accurate characterization of unknown groundwater pollution sources is the uncertainty regarding the number and the location of such sources. Only when the number of source locations is estimated with some degree of certainty that the characterization of the sources in terms of location, magnitude, and activity duration can be meaningful. A fairly good knowledge of source locations can substantially decrease the degree of nonuniqueness in the set of possible aquifer responses to subjected geochemical stresses. A methodology is developed to use a sequence of dedicated monitoring network design and implementation and to screen and identify the possible source locations. The proposed methodology utilizes a combination of spatial interpolation of concentration measurements and simulated annealing as optimization algorithm for optimal design of the monitoring network. These monitoring networks are to be designed and implemented sequentially. The sequential design is based on iterative pollutant concentration measurement information from the sequentially designed monitoring networks. The optimal monitoring network design utilizes concentration gradient information from the monitoring network at previous iteration to define the objective function. The capability of the feedback information based iterative methodology is shown to be effective in estimating the source locations when no such information is initially available. This unknown pollution source locations identification methodology should be very useful as a screening model for subsequent accurate estimation of the unknown pollution sources in terms of location, magnitude, and activity duration.

  6. Estimation of NOx emissions from NO2 hotspots in polluted background using satellite observations

    NASA Astrophysics Data System (ADS)

    Liu, Fei; Beirle, Steffen; Zhang, Qiang; Wagner, Thomas

    2015-04-01

    Satellite observations have been widely used to study NOx emissions from power plants and cities, which are major NOx sources with large impacts on human health and climate. The quantification of NOx emissions from measured column densities of NO2 requires information on the NOx lifetime, which is typically gained from atmospheric chemistry models. But some recent studies determined the NOx lifetime from the satellite observations as well by analyzing the downwind plume evolution; however, this approach was so far only applied for strong isolated 'point sources' located in clean background, like Riyadh in Saudi Arabia. Here we present a modified method for the quantification of NOx emissions and corresponding atmospheric lifetimes based on OMI observations of NO2, together with ECMWF wind fields, but without further model input, for hot spots located in polluted background. We use the observed NO2 patterns under calm wind conditions as proxy for the spatial patterns of NOx emissions; by this approach, even complex source distributions can be treated realistically. From the change of the spatial patterns of NO2 at larger wind speeds (separately for different wind directions), the effective atmospheric lifetime is fitted. Emissions are derived from integrated NO2 columns above background by division by the corresponding lifetime. NOx lifetimes and emissions are estimated for 19 power plants and 50 cities across China and the US. The derived lifetimes are 3.3 ± 1.2 hours on average with extreme values of 0.9 to 7.7 hours. The resulting very short lifetimes for mountainous sites have been found to be uncertain due to the potentially inaccurate ECMWF wind data in mountainous regions. The derived NOx emissions show overall good agreement with bottom-up inventories.

  7. Estimation of monetary values of air pollutant emissions in various US areas

    SciTech Connect

    Wang, M.Q.; Santini, D.J.

    1994-08-17

    Two general methods of estimating monetary values of air pollutants are presented in this paper. The damage estimate method directly estimated, air pollutant by simulating air quality, identifying health and other welfare impacts damage values and valuing the identified impacts of air pollution, and valuing the identified impacts. Although the method is theoretically sound, many assumptions are involved in each of its estimation steps, and uncertainty exists in each step. The control cost estimate method estimates the marginal emission control cost, which represents the opportunity cost offset by emission reductions from some given control measures. Studies conducted to estimate emission values in US regions used either the damage estimate method or the control cost estimate method. Taking emission values estimated for some US air basins, this paper establishes regression relationships between emission values and total population and air pollutant concentrations. On the basis of the established relationships, both damage-based and control-cost-based emission values are estimated for 17 major US urban areas.

  8. Air pollution and survival within the Washington University-EPRI Veterans Cohort: risks based on modelled estimates of ambient levels of hazardous and criteria air pollutants

    SciTech Connect

    Frederick W. Lipfert; Ronald E. Wyzga; Jack D. Baty; J. Philip Miller

    2009-04-15

    For this paper, we considered relationships between mortality, vehicular traffic density, and ambient levels of 12 hazardous air pollutants, elemental carbon (EC), oxides of nitrogen (NOx), sulfur dioxide (SO{sub 2}), and sulfate (SO{sub 4}{sup -2}). These pollutant species were selected as markers for specific types of emission sources, including vehicular traffic, coal combustion, smelters, and metal-working industries. Pollutant exposures were estimated using emissions inventories and atmospheric dispersion models. We analyzed associations between county ambient levels of these pollutants and survival patterns among approximately 70,000 U.S. male veterans by mortality period (1976-2001 and subsets), type of exposure model, and traffic density level. We found significant associations between all-cause mortality and traffic-related air quality indicators and with traffic density per se, with stronger associations for benzene, formaldehyde, diesel particulate, NOx, and EC. The maximum effect on mortality for all cohort subjects during the 26-yr follow-up period is approximately 10%, but most of the pollution-related deaths in this cohort occurred in the higher-traffic counties, where excess risks approach 20%. However, mortality associations with diesel particulates are similar in high- and low-traffic counties. Sensitivity analyses show risks decreasing slightly over time and minor differences between linear and logarithmic exposure models. We conclude that tailpipe emissions of both gases and particles are among the most significant and robust predictors of mortality in this cohort and that most of those associations have weakened over time. There may be concerns associated with large stationary sources burning coal, residual fuel oil and municipal solid wastes. Nickel and arsenic have been identified in coal fly ash and residual oil. 81 refs., 3 figs., 7 tabs.

  9. Estimating Uncertainty in Atmospheric Models - Application and new Approaches of Lyapunov Vector Estimations

    NASA Astrophysics Data System (ADS)

    Keller, J. D.; Hense, A.; Rhodin, A.

    2010-12-01

    The atmosphere, like other geophysical non-linear systems, is chaotic by nature. Therefore, estimating the predictability of the atmosphere is among the main focuses of the scientific community. The degree of chaos or predictability of a system can be expressed by the Lyapunov exponents which represents the temporal growth rate of the distance between two system states initially lying close to another. The corresponding spatial representations of uncertainty are the Lyapunov vectors. The estimation or approximation of Lyapunov vectors is therefore of great interest to the researcher dealing with a chaotic system. However, for the atmosphere estimation methods often tend to approximate the leading Lyapunov vectors or the vectors corresponding to the largest Lyapunov exponents. Depending on the system and situation, smaller Lyapunov exponents may indeed be of more interest. We therefore present research results from two fields of work: (1) uncertainty estimation applied to weather forecasting using techniques adapted to the given practical limitations and (2) idealized Lyapunov analysis using a simple global circulation model (GCM). Perturbation structures intended for ensemble initialization and generated using the Bred Vector (BV) technique for example, tend to converge with the Leading Lyapunov vector disregarding other possibly important information on system/model uncertainty. Our Ensemble Transform Bred Vector (ETBV) approach (Keller et al., 2010) based on the exploitation of the similarities in the BV structures to generate perturbations with different error growth characteristics. We present results from ETBV-driven ensemble forecasts with a global numerical weather prediction model and the performance gain over forecasts driven by simple BVs. We further investigate the effect of downscaling of the resulting large scale uncertainty patterns as forcing for meso-scale weather prediction, thereby testing several different downscaling approaches. We also consider

  10. Comparison of methodologies estimating emissions of aircraft pollutants, environmental impact assessment around airports

    SciTech Connect

    Kurniawan, Jermanto S. Khardi, S.

    2011-04-15

    Air transportation growth has increased continuously over the years. The rise in air transport activity has been accompanied by an increase in the amount of energy used to provide air transportation services. It is also assumed to increase environmental impacts, in particular pollutant emissions. Traditionally, the environmental impacts of atmospheric emissions from aircraft have been addressed in two separate ways; aircraft pollutant emissions occurring during the landing and take-off (LTO) phase (local pollutant emissions) which is the focus of this study, and the non-LTO phase (global/regional pollutant emissions). Aircraft pollutant emissions are an important source of pollution and directly or indirectly harmfully affect human health, ecosystems and cultural heritage. There are many methods to asses pollutant emissions used by various countries. However, using different and separate methodology will cause a variation in results, some lack of information and the use of certain methods will require justification and reliability that must be demonstrated and proven. In relation to this issue, this paper presents identification, comparison and reviews of some of the methodologies of aircraft pollutant assessment from the past, present and future expectations of some studies and projects focusing on emissions factors, fuel consumption, and uncertainty. This paper also provides reliable information on the impacts of aircraft pollutant emissions in short term and long term predictions.

  11. 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

  12. Evaluating the effects of China's pollution control on inter-annual trends and uncertainties of atmospheric mercury emissions

    NASA Astrophysics Data System (ADS)

    Zhao, Y.; Zhong, H.; Zhang, J.; Nielsen, C. P.

    2014-10-01

    China's atmospheric mercury (Hg) emissions of anthropogenic origin have been effectively restrained through the national policy of air pollution control. Improved methods based on available field measurements are developed to quantify the benefits of Hg abatement through various emission control measures. Those measures include increased use of flue gas desulfurization (FGD) and selective catalyst reduction (SCR) systems for power sector, precalciners with fabric filter (FF) for cement production, machinery coking with electrostatic precipitator (ESP) for iron and steel production, and advanced manufacturing technologies for nonferrous metal smelting. Declining trends in emissions factors for those sources are revealed, leading to a much slower growth of national total Hg emissions than that of energy and economy, from 679 in 2005 to 750 metric tons (t) in 2012. In particular, nearly half of emissions from the above-mentioned four types of sources are expected to be reduced in 2012, attributed to expansion of technologies with high energy efficiencies and air pollutant removal rates after 2005. The speciation of Hg emissions keeps stable for recent years, with the mass fractions of around 55, 39 and 6% for Hg0, Hg2+ and Hgp, respectively. The lower estimate of Hg emissions than previous inventories is supported by limited chemistry simulation work, but middle-to-long term observation on ambient Hg levels is further needed to justify the inter-annual trends of estimated Hg emissions. With improved implementation of emission controls and energy saving, 23% reduction in annual Hg emissions for the most optimistic case in 2030 is expected compared to 2012, with total emissions below 600 t. While Hg emissions are evaluated to be gradually constrained, increased uncertainties are quantified with Monte-Carlo simulation for recent years, particularly for power and certain industrial sources. The uncertainty of Hg emissions from coal-fired power plants, as an example

  13. The health and visibility cost of air pollution: a comparison of estimation methods.

    PubMed

    Delucchi, Mark A; Murphy, James J; McCubbin, Donald R

    2002-02-01

    Air pollution from motor vehicles, electricity-generating plants, industry, and other sources can harm human health, injure crops and forests, damage building materials, and impair visibility. Economists sometimes analyze the social cost of these impacts, in order to illuminate tradeoffs, compare alternatives, and promote efficient use of scarce resource. In this paper, we compare estimates of the health and visibility costs of air pollution derived from a meta-hedonic price analysis, with an estimate of health costs derived from a damage-function analysis and an estimate of the visibility cost derived from contingent valuation. We find that the meta-hedonic price analysis produces an estimate of the health cost that lies at the low end of the range of damage-function estimates. This is consistent with hypotheses that on the one hand, hedonic price analysis does not capture all of the health costs of air pollution (because individuals may not be fully informed about all of the health effects), and that on the other hand, the value of mortality used in the high-end damage function estimates is too high. The analysis of the visibility cost of air pollution derived from a meta-hedonic price analysis produces an estimate that is essentially identical to an independent estimate based on contingent valuation. This close agreement lends some credence to the estimates. We then apply the meta hedonic-price model to estimate the visibility cost per kilogram of motor vehicle emissions.

  14. 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

  15. Atmospheric dispersion estimates in the vicinity of buildings

    SciTech Connect

    Ramsdell, J.V. Jr.; Fosmire, C.J.

    1995-01-01

    A model describing atmospheric dispersion in the vicinity of buildings was developed for the U.S. Nuclear Regulatory Commission (NRC) in the late 1980s. That model has recently undergone additional peer review. The reviewers identified four areas of concern related to the model and its application. This report describes revisions to the model in response to the reviewers concerns. Model revision involved incorporation of explicit treatment of enhanced dispersion at low wind speeds in addition to explicit treatment of enhanced dispersion at high speeds resulting from building wakes. Model parameters are evaluated from turbulence data. Experimental diffusion data from seven reactor sites are used for model evaluation. Compared with models recommended in current NRC guidance to licensees, the revised model is less biased and shows more predictive skill. The revised model is also compared with two non-Gaussian models developed to estimate maximum concentrations in building wakes. The revised model concentration predictions are nearly the same as the predictions of the non-Gaussian models. On the basis of these comparisons of the revised model concentration predictions with experimental data and the predictions of other models, the revised model is found to be an appropriate model for estimating concentrations in the vicinity of buildings.

  16. 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

    Air pollution is determined by the combination of different factors, namely, emissions, physical constrains, meteorology and chemical processes [1,2,3]. The relative importance of such factors is influenced by their interaction on diverse scales of atmospheric motion. Each scale depicts different meteorological conditions, which, when combined with the different air pollution sources and photochemistry, result in varying ambient concentrations [2]. Identifying the dominant scales of atmospheric motion over a given airshed can be of great importance for many applications such as air pollution and pollen dispersion or wind energy management [2]. Portugal has been affected by numerous air pollution episodes during the last decade. These episodes are often related to peak emissions from local industry or transport, but can also be associated to regional transport from other urban areas or to exceptional emission events, such as forest fires. This research aims to identify the scales of atmospheric motion which contribute to an increase of air pollution. A method is proposed for differentiating between the scales of atmospheric motion that can be applied on a daily basis from data collected at several wind-measuring sites in a given airshed and to reanalysis datasets. The method is based on the daily mean wind recirculation and the mean and standard deviation between sites. The determination of the thresholds between scales is performed empirically following the approach of Levy et al. [2] and also through a automatic statistical approach computed taking into account the tails of the distributions (e.g. 95% and 99% percentile) of the different wind samples. A comparison is made with two objective approaches: 1) daily synoptic classification for the same period over the region [4] and 2) a 3-D backward trajectory approach [5,6] for specific episodes. Furthermore, the outcomes are expected to support the Portuguese authorities on the implementation of strategies for a

  17. 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.

  18. [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).

  19. [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.

  20. 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

  1. 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

  2. Statistical estimate of mercury removal efficiencies for air pollution control devices of municipal solid waste incinerators.

    PubMed

    Takahashi, Fumitake; Kida, Akiko; Shimaoka, Takayuki

    2010-10-15

    Although representative removal efficiencies of gaseous mercury for air pollution control devices (APCDs) are important to prepare more reliable atmospheric emission inventories of mercury, they have been still uncertain because they depend sensitively on many factors like the type of APCDs, gas temperature, and mercury speciation. In this study, representative removal efficiencies of gaseous mercury for several types of APCDs of municipal solid waste incineration (MSWI) were offered using a statistical method. 534 data of mercury removal efficiencies for APCDs used in MSWI were collected. APCDs were categorized as fixed-bed absorber (FA), wet scrubber (WS), electrostatic precipitator (ESP), and fabric filter (FF), and their hybrid systems. Data series of all APCD types had Gaussian log-normality. The average removal efficiency with a 95% confidence interval for each APCD was estimated. The FA, WS, and FF with carbon and/or dry sorbent injection systems had 75% to 82% average removal efficiencies. On the other hand, the ESP with/without dry sorbent injection had lower removal efficiencies of up to 22%. The type of dry sorbent injection in the FF system, dry or semi-dry, did not make more than 1% difference to the removal efficiency. The injection of activated carbon and carbon-containing fly ash in the FF system made less than 3% difference. Estimation errors of removal efficiency were especially high for the ESP. The national average of removal efficiency of APCDs in Japanese MSWI plants was estimated on the basis of incineration capacity. Owing to the replacement of old APCDs for dioxin control, the national average removal efficiency increased from 34.5% in 1991 to 92.5% in 2003. This resulted in an additional reduction of about 0.86Mg emission in 2003. Further study using the methodology in this study to other important emission sources like coal-fired power plants will contribute to better emission inventories.

  3. 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

    Processes on icy particles attract much attention due to their importance for atmospheric science, ecology and astrophysics. In this work, adsorption and ecologically important reactions of some molecules on pure and mixed water icy films by means of FTIR spectroscopy have been investigated. The cell for spectral studies of adsorbed molecules at variable temperatures (55-370 K), described elsewhere1, enables one to run the spectra in the presence of gaseous adsorbate, and even to perform adsorption from the solution in some cryogenic solvents. For the studies of ice films, it was equipped with a device for water vapour sputtering from the heated capillaries and deposition onto the inner BaF2 or ZnSe windows of the cell, cooled by liquid nitrogen. Lower temperatures were obtained by pumping off evaporating nitrogen from the coolant volume. The estimated specific surface area of freshly deposited at 77 K water ice film was about 160 m2/g and decreases on raising the temperature together with the diminishing intensity of the bands of dangling OH (OD) groups at 3696 (2727) cm-1 until the latter disappear at 130 - 160 K when the changes of bulk absorption provide evidence for a phase transition from amorphous to polycrystalline ice. CO adsorption at 77 K results in two bands at 2153 and 2137 cm-1 assigned to molecules forming weak H-bond with the dangling hydroxyl groups and bound to unsaturated surface oxygen atoms, respectively2. The band of dangling hydroxyl groups moves to lower wavenumbers on adsorption of different molecules (hydrogen, nitrogen, methane, ozone, NO, ethane or chlorinated ethenes, etc.). The shift value depends on the nature of adsorbate. Besides this shift, spectra of adsorbed nitrogen and methane registered at 55 K reveal the adsorption intensity decrease at ~ 2650 cm-1 at the high-frequency slope of bulk adsorption, and increase at about 25 cm-1 below. We interpret this perturbation as a strengthening of H-bonds between surface water molecules

  4. 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.

  5. Aerosol physical, chemical and optical properties observed in the ambient atmosphere during haze pollution conditions

    NASA Astrophysics Data System (ADS)

    Li, Zhengqiang; Xie, Yisong; Li, Donghui; Li, Kaitao; Zhang, Ying; Li, Li; Lv, Yang; Qie, Lili; Xu, Hua

    Aerosol’s properties in the ambient atmosphere may differ significantly from sampling results due to containing of abundant water content. We performed sun-sky radiometer measurements in Beijing during 2011 and 2012 winter to obtain distribution of spectral and angular sky radiance. The measurements are then used to retrieve aerosol physical, chemical and optical properties, including single scattering albedo, size distribution, complex refractive indices and aerosol component fractions identified as black carbon, brown carbon, mineral dust, ammonium sulfate-like components and water content inside particle matters. We found that during winter haze condition aerosol is dominated by fine particles with center radius of about 0.2 micron. Fine particles contribute about 93% to total aerosol extinction of solar light, and result in serious decrease of atmospheric visibility during haze condition. The percentage of light absorption of haze aerosol can up to about 10% among its total extinction, much higher than that of unpolluted conditions, that causes significant radiative cooling effects suppressing atmospheric convection and dispersion of pollutants. Moreover, the average water content occupies about one third of the ambient aerosol in volume which suggests the important effect of ambient humidity in the formation of haze pollution.

  6. 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.

  7. 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

  8. Growing Atmospheric Pollution and Its Relation with Occurrences of Natural Hazards in India

    NASA Astrophysics Data System (ADS)

    Singh, Ramesh

    In the last three decades, multi satellite remote sensing data have revealed increasing atmospheric pollution. The satellite data have shown spatial distribution of fine and coarse atmospheric particles which impact human health, cloud albedo and atmospheric and meteorological parameters. The long range dusts coming over India travel through Arabian Sea and reach to the Bay of Bengal, such long range transport of dust influences atmospheric and ocean parameters, as a result strong coupling exists between land-ocean-atmosphere. Various kind of natural hazards, such as cyclone, algal bloom, cloud burst, excessive rainfall have been observed apart from the intense fog, haze and smog during winter and post monsoon seasons that have serious impacts on human health of people living in the Indo-Gangetic basin. The long range transport of dust and local anthropogenic emissions also reach to the Himalayan region affecting snow and glaciers of Himalaya and accelerating melting of snow and glaciers which is a threat of flooding of rivers originate from Himalayan region.

  9. A sparse reconstruction method for the estimation of multiresolution emission fields via atmospheric inversion

    DOE PAGES

    Ray, J.; Lee, J.; Yadav, V.; ...

    2014-08-20

    We present a sparse reconstruction scheme that can also be used to ensure non-negativity when fitting wavelet-based random field models to limited observations in non-rectangular geometries. The method is relevant when multiresolution fields are estimated using linear inverse problems. Examples include the estimation of emission fields for many anthropogenic pollutants using atmospheric inversion or hydraulic conductivity in aquifers from flow measurements. The scheme is based on three new developments. Firstly, we extend an existing sparse reconstruction method, Stagewise Orthogonal Matching Pursuit (StOMP), to incorporate prior information on the target field. Secondly, we develop an iterative method that uses StOMP tomore » impose non-negativity on the estimated field. Finally, we devise a method, based on compressive sensing, to limit the estimated field within an irregularly shaped domain. We demonstrate the method on the estimation of fossil-fuel CO2 (ffCO2) emissions in the lower 48 states of the US. The application uses a recently developed multiresolution random field model and synthetic observations of ffCO2 concentrations from a limited set of measurement sites. We find that our method for limiting the estimated field within an irregularly shaped region is about a factor of 10 faster than conventional approaches. It also reduces the overall computational cost by a factor of two. Further, the sparse reconstruction scheme imposes non-negativity without introducing strong nonlinearities, such as those introduced by employing log-transformed fields, and thus reaps the benefits of simplicity and computational speed that are characteristic of linear inverse problems.« less

  10. 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

  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. 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

  13. The linear accumulation of atmospheric mercury by vegetable and grass leaves: Potential biomonitors for atmospheric mercury pollution.

    PubMed

    Niu, Zhenchuan; Zhang, Xiaoshan; Wang, Sen; Ci, Zhijia; Kong, Xiangrui; Wang, Zhangwei

    2013-09-01

    One question in the use of plants as biomonitors for atmospheric mercury (Hg) is to confirm the linear relationships of Hg concentrations between air and leaves. To explore the origin of Hg in the vegetable and grass leaves, open top chambers (OTCs) experiment was conducted to study the relationships of Hg concentrations between air and leaves of lettuce (Lactuca sativa L.), radish (Raphanus sativus L.), alfalfa (Medicago sativa L.) and ryegrass (Lolium perenne L.). The influence of Hg in soil on Hg accumulation in leaves was studied simultaneously by soil Hg-enriched experiment. Hg concentrations in grass and vegetable leaves and roots were measured in both experiments. Results from OTCs experiment showed that Hg concentrations in leaves of the four species were significantly positively correlated with those in air during the growth time (p < 0.05), while results from soil Hg-enriched experiment indicated that soil-borne Hg had significant influence on Hg accumulation in the roots of each plant (p < 0.05), and some influence on vegetable leaves (p < 0.05), but no significant influence on Hg accumulation in grass leaves (p > 0.05). Thus, Hg in grass leaves is mainly originated from the atmosphere, and grass leaves are more suitable as potential biomonitors for atmospheric Hg pollution. The effect detection limits (EDLs) for the leaves of alfalfa and ryegrass were 15.1 and 22.2 ng g(-1), respectively, and the biological detection limit (BDL) for alfalfa and ryegrass was 3.4 ng m(-3).

  14. The atmospheric photooxidation cycle and the influence of troposphere pollution on ozone - A review

    NASA Astrophysics Data System (ADS)

    Demerjian, K. L.

    The state of knowledge on the nature and occurrence of ozone in the clean and polluted troposphere is surveyed in the light of the present understanding of the atmospheric photochemical oxidation cycle. A review is also given of the knowledge of the chemical state of the clean, unpolluted troposphere; this provides the basis for assessing the nature and magnitude of effects that human activities have on atmospheric processes. Since it is not considered possible to address the chemistry of ozone without considering the chemistry of oxides of nitrogen and carbon (owing to the interactive nature of their chemical processes) the chemistry of these compounds is discussed. It is shown how the photochemistry of the unpolluted troposphere develops around a chain reaction sequence involving NO, CH4, CO, and O3.

  15. Atmospheric air pollutants: CO in Nitrogen, 5 μmol/mol

    NASA Astrophysics Data System (ADS)

    Konopelko, L. A.; Pankratov, V. V.; Pankov, A. A.; Ivahnenko, B. V.; Efremova, O. V.; Bakovec, N. V.; Mironchik, A. M.; Aleksandrov, V. V.

    2017-01-01

    This article presents the report on the COOMET supplementary comparison "Atmospheric air pollutants: CO in Nitrogen, 5 μmol/mol". Carbon monoxide (CO) is present in atmosphere due to different natural and anthropogenic sources. CO is a toxic gas and in concentrations higher than (3-5) μmol/mol it is hazardous to human health. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  16. 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.

  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. Analysis of forest environmental measurements to estimate parameters of microclimate and air-pollution deposition-velocity models

    SciTech Connect

    Murphy, Jr, C E; Lorenz, R

    1983-01-01

    A method is described for estimating flux densities and deposition of gaseous pollutants for a period of a year or more, using data collected for a period of a few days. The estimates are based on models which characterize the transfer of gases from the atmosphere to the vegetation as a series of resistances and then use linear statistical submodels based on experimental data to relate the resistances to the surrounding environment. The models are shown to fit the experimental data reasonably well. Annual values calculated for a young loblolly pine plantation were: evaporation 63.2 cm, carbon dioxide exchange 31.5 t/ha, and sulfur dioxide exchange 120 gm/ha. 17 references.

  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. A review of existing models and methods to estimate employment effects of pollution control policies

    SciTech Connect

    Darwin, R.F.; Nesse, R.J.

    1988-02-01

    The purpose of this paper is to provide information about existing models and methods used to estimate coal mining employment impacts of pollution control policies. The EPA is currently assessing the consequences of various alternative policies to reduce air pollution. One important potential consequence of these policies is that coal mining employment may decline or shift from low-sulfur to high-sulfur coal producing regions. The EPA requires models that can estimate the magnitude and cost of these employment changes at the local level. This paper contains descriptions and evaluations of three models and methods currently used to estimate the size and cost of coal mining employment changes. The first model reviewed is the Coal and Electric Utilities Model (CEUM), a well established, general purpose model that has been used by the EPA and other groups to simulate air pollution control policies. The second model reviewed is the Advanced Utility Simulation Model (AUSM), which was developed for the EPA specifically to analyze the impacts of air pollution control policies. Finally, the methodology used by Arthur D. Little, Inc. to estimate the costs of alternative air pollution control policies for the Consolidated Coal Company is discussed. These descriptions and evaluations are based on information obtained from published reports and from draft documentation of the models provided by the EPA. 12 refs., 1 fig.

  2. Mass identification of the neutral products generated in the plasma treatment of polluted atmospheres

    NASA Astrophysics Data System (ADS)

    Seymour, David

    2013-09-01

    Plasmas produced using Dielectric Barrier Discharge (DBD) devices are very effective in the abatement of air pollution resulting from, for example, the emission of volatile organic compounds (VCOs) by a range of industrial and agricultural processes. The development and monitoring of effective DBD systems can be investigated by advanced mass spectrometric methods specifically configured for analysis at high and atmospheric pressures The present work involves the operation of a small DBD reactor which uses either a helium or nitrogen carrier gas to sustain the plasma to which may be added reactive gases, such as oxygen, as well as samples of pollutants such as chlorinated hydrocarbons, including trichloroethylene. The mass spectrometric analysis was performed using a specially configured system manufactured by Hiden Analytical Ltd. The DBD source may also be combined with a catalyst for plasma-enhanced catalysis. The neutral products of the reactions proceeding in the plasma at atmospheric pressure are sampled through the capillary sampling system which also reduces the pressure of the gas mixture delivered to the ionisation source of the quadrupole mass spectrometer. The ions produced are subsequently mass identified. We describe typical data and comment on the advantages of this technique.

  3. 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.

  4. Hydrogen in the atmosphere: Observations above a forest canopy in a polluted environment

    NASA Astrophysics Data System (ADS)

    Barnes, Diana H.; Wofsy, Steven C.; Fehlau, Brian P.; Gottlieb, Elaine W.; Elkins, James W.; Dutton, Geoffrey S.; Novelli, Paul C.

    2003-03-01

    Long-term in situ observations of atmospheric concentrations of molecular hydrogen were monitored every 24 minutes for three years (1996-1998) above Harvard Forest, Massachusetts, in concert with measurements of carbon monoxide and twelve other trace gases. A seasonal cycle with a spring maximum and autumn minimum was observed. The diurnal cycle was characterized by a morning minimum and an afternoon maximum, reflecting the combined effects of uptake by soils and boundary height fluctuations. Enhancements of H2 concentrations in pollution events, concurrent with winds from the southwest, were typically 100-200 ppb above the background seasonal cycle. The mean molar ratio of H2 and CO (ΔH2/ΔCO) in pollution plumes was 0.396 ± 0.050 ppb/ppb. The results agree with expectations from the water-gas equilibrium (CO + H2O ↔ CO2 + H2) for conditions in automobile engines and with car emission data. These observations suggest that automobiles are the major anthropogenic source of atmospheric hydrogen and that the ratio of ΔH2/ΔCO has changed little as emission controls have taken effect.

  5. Estimating years of life lost from cardiovascular mortality related to air pollution in Guangzhou, China.

    PubMed

    Yang, Jun; Ou, Chun-Quan; Song, Yu-Feng; Li, Li; Chen, Ping-Yan; Liu, Qi-Yong

    2016-12-15

    Previous studies have mainly used mortality or morbidity as the health outcome to examine the air pollution-health association. Little evidence is available on relationships between air pollutants and years of life lost (YLL). We aimed to estimate the YLL from cardiovascular mortality due to air pollution. Daily data on weather and air pollutants and individual data of all registered deaths for years 2004-2007 were obtained in Guangzhou, China. The generalized additive model was used to assess the YLL associated with 10μg/m(3) increases in NO2, SO2 and PM10. We found that the mean daily YLL was 248, 87.5 and 73.7 for deaths from cardiovascular disease (CVD), stroke and ischemic heart disease (IHD), respectively. A significant linear correlation was observed between air pollution and YLL due to cardiovascular disease. The effects of air pollutants on YLL were immediate and lasted for two days. A 10μg/m(3) increase above the corresponding threshold of 55.6μg/m(3), 40.4μg/m(3) and 0μg/m(3) in NO2, PM10 and SO2 was related to YLL increase of 1.8 (95% CI: 0.8-2.9), 2.8 (1.7-3.8) and 2.6 (1.2-4.0) years at lag 0-1days for CVD, respectively. The estimates of YLL associated with NO2 and PM10 were higher in men than women. The air pollutants-related YLL was higher among young people and those with low education level, compared to the elderly and those with high education level, respectively. These findings confirmed YLL provides a complementary strategy for assessing the health effect of air pollution. This study underscores the necessity of the reduction of air pollution benefiting public health.

  6. 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.

  7. 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

  8. 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.

  9. A quarter century of biomonitoring atmospheric pollution in the Czech Republic.

    PubMed

    Suchara, Ivan; Sucharová, Julie; Holá, Marie

    2015-09-21

    The Czech Republic (CZ) had extremely high emissions and atmospheric deposition of pollutants in the second half of the 1980s. Since the beginning of the 1990s, moss, spruce bark and forest floor humus have been used as bioindicators of air quality. In the first half of the 1990s, seven larger areas were found to be affected by high atmospheric deposition loads. Six of these "hot spots" were caused by industrial pollution sources, mainly situated in coal basins in the NW and NE part of the country, and one large area in the SE was affected by increased deposition loads of eroded soil particles. After restructuring of industry in CZ, these hot spots were substantially reduced or even disappeared between 1995 and 2000. Since 2000, only two larger areas with slightly increased levels of industrial pollutant deposition and a larger area affected by soil dust have repeatedly been identified by biomonitoring. The distribution of lead isotope ratios in moss showed the main deposition zones around important emission sources. Very high SO2 emissions led to extreme acidity of spruce bark extracts (pH of about 2.3) at the end of the 1980s. The rate of increasing bark pH was strikingly similar to the rate of recovery of acid wet deposition measured at forest stations in CZ. By about 2005, when the median pH value in bark increased to about 3.2, the re-colonisation of trees by several epiphyte lichen species was observed throughout CZ. An increase in the accumulation of Chernobyl-derived (137)Cs in bark was detected at about ten sites affected by precipitation during the time when radioactive plumes crossed CZ (1986). Accumulated deposition loads in forest floor humus corresponded to the position of the moss and bark hot spots.

  10. 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.

  11. Estimation of economic costs of particulate air pollution from road transport in China

    NASA Astrophysics Data System (ADS)

    Guo, X. R.; Cheng, S. Y.; Chen, D. S.; Zhou, Y.; Wang, H. Y.

    2010-09-01

    Valuation of health effects of air pollution is becoming a critical component of the performance of cost-benefit analysis of pollution control measures, which provides a basis for setting priorities for action. Beijing has focused on control of transport emission as vehicular emissions have recently become an important source of air pollution, particularly during Olympic games and Post-games. In this paper, we conducted an estimation of health effects and economic cost caused by road transport-related air pollution using an integrated assessment approach which utilizes air quality model, engineering, epidemiology, and economics. The results show that the total economic cost of health impacts due to air pollution contributed from transport in Beijing during 2004-2008 was 272, 297, 310, 323, 298 million US (mean value), respectively. The economic costs of road transport accounted for 0.52, 0.57, 0.60, 0.62, and 0.58% of annual Beijing GDP from 2004 to 2008. Average cost per vehicle and per ton of PM 10 emission from road transport can also be estimated as 106 US /number and 3584 US $ t -1, respectively. These findings illustrate that the impact of road transport contributed particulate air pollution on human health could be substantial in Beijing, whether in physical and economic terms. Therefore, some control measures to reduce transport emissions could lead to considerable economic benefit.

  12. [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-).

  13. Estimating sources, sinks and fluxes of reactive atmospheric compounds within a forest canopy

    NASA Astrophysics Data System (ADS)

    Ghannam, K.; Duman, T.; Walker, J. T.; Bash, J. O.; Huang, C. W.; Khlystov, A.; Katul, G. G.

    2015-12-01

    While few dispute the significance of within-canopy sources or sinks of reactive gaseous and particulate compounds, their estimation continues to be the subject of active research and debate. Reactive species undergo turbulent dispersion within an inhomogeneous flow field, and may be subjected to chemical, biological and/or physical deposition, emissions or transformations on leaves, woody elements, and the forest floor. This system involves chemical reactions and biological processes with multiple time scales and represents the terrestrial ecosystem's exposure to nutrient and acid deposition and atmospheric oxidants. The quantification of these processes is a first step in better understanding the ecological impact of air pollution and feedback to atmospheric composition. Hence, it follows that direct measurements of sources or sinks is difficult to conduct in the presence of all these processes. However, mean scalar concentration profiles measured within the canopy can be used to infer the profile distribution of effective sinks and sources if the flow field is known. This is commonly referred to as the 'inverse problem'. In-canopy and above-canopy multi-level concentration measurements of reactive nitrogen compounds (ammonia, nitric acid, nitrous acid), as well as other compounds that are highly reactive to ammonia and its secondary products (hydrochloric acid and sulfur dioxide), are presented within a deciduous second-growth 180 year old oak-hickory forest situated within the Southeastern U.S. Two different approaches are used to solve for the source-sink distribution from the measured mean scalar concentration profiles: (1) an Eulerian high-order closure model that solves the scalar flux budget equation and (2) a new Lagrangian stochastic model that estimates the dispersion matrix. As each of these methods is subject to different assumptions, the combination of the two can be used to constrain the solution to the inverse problem and permit inference on the

  14. [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.

  15. 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.

  16. Spectral Dark Subtraction: A MODTRAN-Based Algorithm for Estimating Ground Reflectance without Atmospheric Information

    NASA Technical Reports Server (NTRS)

    Freedman, Ellis; Ryan, Robert; Pagnutti, Mary; Holekamp, Kara; Gasser, Gerald; Carver, David; Greer, Randy

    2007-01-01

    Spectral Dark Subtraction (SDS) provides good ground reflectance estimates across a variety of atmospheric conditions with no knowledge of those conditions. The algorithm may be sensitive to errors from stray light, calibration, and excessive haze/water vapor. SDS seems to provide better estimates than traditional algorithms using on-site atmospheric measurements much of the time.

  17. Atmospheric ammonia over China: emission estimates and impacts on air quality

    NASA Astrophysics Data System (ADS)

    Zhang, Lin; Zhao, Yuanhong; Chen, Youfan; Henze, Daven

    2016-04-01

    Ammonia (NH3) in the atmosphere is an important precursor of inorganic aerosols, and its deposition through wet and dry processes can cause adverse effects on ecosystems. The ammonia emissions over China are particularly large due to intensive agricultural activities, yet our current estimates of Chinese ammonia emissions and associated consequences on air quality are subject to large errors. Here we use the GEOS-Chem chemical transport model and its adjoint model to better quantify this issue. The TES satellite observations of ammonia concentrations and surface measurements of wet deposition fluxes are assimilated into the model to constrain the ammonia emissions over China. Optimized emissions show a strong seasonal variability with emissions in summer a factor of 3 higher than winter. We improve the bottom-up estimate of Chinese ammonia emissions from fertilizer use by using more practical feritilizer application rates for different crop types, which explains most of the discrepancies between our top-down estimates and prior emission estimates. We further use the GEOS-Chem adjoint at 0.25x0.3125 degree resolution to examine the sources contributing to the PM2.5 air pollution over North China. We show that wintertime PM2.5 over Beijing is largely contributed by residential and industrial sources, and ammonia emissions from agriculture activities. PM2.5 concentrations over North China are particularly sensitive to NH3 emissions in cold seasons due to strong nitrate formation. By converting shorted-lived nitric acid to aerosol nitrate, NH3 significantly promotes the regional transport influences of PM2.5 sources.

  18. 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

  19. 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

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

    PubMed Central

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

    2014-01-01

    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. PMID:25335435

  1. 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.

  2. Power estimation using simulations for air pollution time-series studies

    PubMed Central

    2012-01-01

    Background Estimation of power to assess associations of interest can be challenging for time-series studies of the acute health effects of air pollution because there are two dimensions of sample size (time-series length and daily outcome counts), and because these studies often use generalized linear models to control for complex patterns of covariation between pollutants and time trends, meteorology and possibly other pollutants. In general, statistical software packages for power estimation rely on simplifying assumptions that may not adequately capture this complexity. Here we examine the impact of various factors affecting power using simulations, with comparison of power estimates obtained from simulations with those obtained using statistical software. Methods Power was estimated for various analyses within a time-series study of air pollution and emergency department visits using simulations for specified scenarios. Mean daily emergency department visit counts, model parameter value estimates and daily values for air pollution and meteorological variables from actual data (8/1/98 to 7/31/99 in Atlanta) were used to generate simulated daily outcome counts with specified temporal associations with air pollutants and randomly generated error based on a Poisson distribution. Power was estimated by conducting analyses of the association between simulated daily outcome counts and air pollution in 2000 data sets for each scenario. Power estimates from simulations and statistical software (G*Power and PASS) were compared. Results In the simulation results, increasing time-series length and average daily outcome counts both increased power to a similar extent. Our results also illustrate the low power that can result from using outcomes with low daily counts or short time series, and the reduction in power that can accompany use of multipollutant models. Power estimates obtained using standard statistical software were very similar to those from the simulations

  3. 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)

  4. Computed and estimated pollutant loads, West Fork Trinity River, Fort Worth, Texas, 1997

    USGS Publications Warehouse

    McKee, Paul W.; McWreath, Harry C.

    2001-01-01

    In 1998 the U.S. Geological Survey, in cooperation with the Trinity River Authority, did a study to estimate storm-runoff pollutant loads using two models—a deterministic model and a statistical model; the estimated loads were compared to loads computed from measured data for a large (118,000 acres) basin in the Dallas-Fort Worth, Texas, metropolitan area. Loads were computed and estimated for 12 properties and constituents in runoff from two 1997 storms at streamflow-gaging station 08048543 West Fork Trinity River at Beach Street in Fort Worth. Each model uses rainfall as a primary variable to estimate pollutant load. In addition to using point rainfall at the Beach Street station to estimate pollutant loads, areal-averaged rainfall for the basin was computed to obtain a more representative estimate of rainfall over the basin. Loads estimated by the models for the two storms, using both point and areal-averaged rainfall, generally did not compare closely to computed loads for the 12 water-quality properties and constituents. Both models overestimated loads more frequently than they underestimated loads. The models tended to yield similar estimates for the same property or constituent. In general, areal-averaged rainfall data yielded better estimates of loads than point rainfall data for both models. Neither the deterministic model nor the statistical model (both using areal-averaged rainfall) was consistently better at estimating loads. Several factors could account for the inability of the models to estimate loads closer to computed loads. Chief among them is the fact that neither model was designed for the specific application of this study.

  5. Effect of geocoding errors on traffic-related air pollutant exposure and concentration estimates

    EPA Science Inventory

    Exposure to traffic-related air pollutants is highest very near roads, and thus exposure estimates are sensitive to positional errors. This study evaluates positional and PM2.5 concentration errors that result from the use of automated geocoding methods and from linearized approx...

  6. ESTIMATION OF GROUNDWATER POLLUTION POTENTIAL BY PESTICIDES IN MID-ATLANTIC COASTAL PLAIN WATERSHEDS

    EPA Science Inventory

    A simple GIS-based transport model to estimate the potential for groundwater pollution by pesticides has been developed within the ArcView GIS environment. The pesticide leaching analytical model, which is based on one-dimensional advective-dispersive-reactive (ADR) transport, ha...

  7. Evaluation of the use of remotely sensed evapotranspiration estimates into AnnAGNPS pollution model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The utilization of evapotranspiration (ET) estimates, derived from satellite remote sensing, into the Annualized Agricultural Non-Point Source (AnnAGNPS) pollution model was investigated. Modifications within AnnAGNPS were performed to allow the internal calculations of ET based on climate parameter...

  8. An Estimate of the Global Burden of Anthropogenic Ozone and Fine Particulate Matter on Premature Human Mortality Using Atmospheric Modeling

    PubMed Central

    Anenberg, Susan C.; Horowitz, Larry W.; Tong, Daniel Q.; West, J. Jason

    2010-01-01

    Background Ground-level concentrations of ozone (O3) and fine particulate matter [≤ 2.5 μm in aerodynamic diameter (PM2.5)] have increased since preindustrial times in urban and rural regions and are associated with cardiovascular and respiratory mortality. Objectives We estimated the global burden of mortality due to O3 and PM2.5 from anthropogenic emissions using global atmospheric chemical transport model simulations of preindustrial and present-day (2000) concentrations to derive exposure estimates. Methods Attributable mortalities were estimated using health impact functions based on long-term relative risk estimates for O3 and PM2.5 from the epidemiology literature. Using simulated concentrations rather than previous methods based on measurements allows the inclusion of rural areas where measurements are often unavailable and avoids making assumptions for background air pollution. Results Anthropogenic O3 was associated with an estimated 0.7 ± 0.3 million respiratory mortalities (6.3 ± 3.0 million years of life lost) annually. Anthropogenic PM2.5 was associated with 3.5 ± 0.9 million cardiopulmonary and 220,000 ± 80,000 lung cancer mortalities (30 ± 7.6 million years of life lost) annually. Mortality estimates were reduced approximately 30% when we assumed low-concentration thresholds of 33.3 ppb for O3 and 5.8 μg/m3 for PM2.5. These estimates were sensitive to concentration thresholds and concentration–mortality relationships, often by > 50%. Conclusions Anthropogenic O3 and PM2.5 contribute substantially to global premature mortality. PM2.5 mortality estimates are about 50% higher than previous measurement-based estimates based on common assumptions, mainly because of methodologic differences. Specifically, we included rural populations, suggesting higher estimates; however, the coarse resolution of the global atmospheric model may underestimate urban PM2.5 exposures. PMID:20382579

  9. Simultaneous estimation of model parameters and diffuse pollution sources for river water quality modeling.

    PubMed

    Jun, K S; Kang, J W; Lee, K S

    2007-01-01

    Diffuse pollution sources along a stream reach are very difficult to both monitor and estimate. In this paper, a systematic method using an optimal estimation algorithm is presented for simultaneous estimation of diffuse pollution and model parameters in a stream water quality model. It was applied with the QUAL2E model to the South Han River in South Korea for optimal estimation of kinetic constants and diffuse loads along the river. Initial calibration results for kinetic constants selected from a sensitivity analysis reveal that diffuse source inputs for nitrogen and phosphorus are essential to satisfy the system mass balance. Diffuse loads for total nitrogen and total phosphorus were estimated by solving the expanded inverse problem. Comparison of kinetic constants estimated simultaneously with diffuse sources to those estimated without diffuse loads, suggests that diffuse sources must be included in the optimization not only for its own estimation but also for adequate estimation of the model parameters. Application of the optimization method to river water quality modeling is discussed in terms of the sensitivity coefficient matrix structure.

  10. Coupled Inertial Navigation and Flush Air Data Sensing Algorithm for Atmosphere Estimation

    NASA Technical Reports Server (NTRS)

    Karlgaard, Christopher D.; Kutty, Prasad; Schoenenberger, Mark

    2016-01-01

    This paper describes an algorithm for atmospheric state estimation based on a coupling between inertial navigation and flush air data-sensing pressure measurements. The navigation state is used in the atmospheric estimation algorithm along with the pressure measurements and a model of the surface pressure distribution to estimate the atmosphere using a nonlinear weighted least-squares algorithm. The approach uses a high-fidelity model of atmosphere stored in table-lookup form, along with simplified models propagated along the trajectory within the algorithm to aid the solution. Thus, the method is a reduced-order Kalman filter in which the inertial states are taken from the navigation solution and atmospheric states are estimated in the filter. The algorithm is applied to data from the Mars Science Laboratory entry, descent, and landing from August 2012. Reasonable estimates of the atmosphere are produced by the algorithm. The observability of winds along the trajectory are examined using an index based on the observability Gramian and the pressure measurement sensitivity matrix. The results indicate that bank reversals are responsible for adding information content. The algorithm is applied to the design of the pressure measurement system for the Mars 2020 mission. A linear covariance analysis is performed to assess estimator performance. The results indicate that the new estimator produces more precise estimates of atmospheric states than existing algorithms.

  11. 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.

  12. 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.

  13. 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.

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

    PubMed

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

    2014-07-01

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

  15. 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.

  16. Soil TPH concentration estimation using vegetation indices in an oil polluted area of eastern China.

    PubMed

    Zhu, Linhai; Zhao, Xuechun; Lai, Liming; Wang, Jianjian; Jiang, Lianhe; Ding, Jinzhi; Liu, Nanxi; Yu, Yunjiang; Li, Junsheng; Xiao, Nengwen; Zheng, Yuanrun; Rimmington, Glyn M

    2013-01-01

    Assessing oil pollution using traditional field-based methods over large areas is difficult and expensive. Remote sensing technologies with good spatial and temporal coverage might provide an alternative for monitoring oil pollution by recording the spectral signals of plants growing in polluted soils. Total petroleum hydrocarbon concentrations of soils and the hyperspectral canopy reflectance were measured in wetlands dominated by reeds (Phragmites australis) around oil wells that have been producing oil for approximately 10 years in the Yellow River Delta, eastern China to evaluate the potential of vegetation indices and red edge parameters to estimate soil oil pollution. The detrimental effect of oil pollution on reed communities was confirmed by the evidence that the aboveground biomass decreased from 1076.5 g m(-2) to 5.3 g m(-2) with increasing total petroleum hydrocarbon concentrations ranging from 9.45 mg kg(-1) to 652 mg kg(-1). The modified chlorophyll absorption ratio index (MCARI) best estimated soil TPH concentration among 20 vegetation indices. The linear model involving MCARI had the highest coefficient of determination (R(2) = 0.73) and accuracy of prediction (RMSE = 104.2 mg kg(-1)). For other vegetation indices and red edge parameters, the R(2) and RMSE values ranged from 0.64 to 0.71 and from 120.2 mg kg(-1) to 106.8 mg kg(-1) respectively. The traditional broadband normalized difference vegetation index (NDVI), one of the broadband multispectral vegetation indices (BMVIs), produced a prediction (R(2) = 0.70 and RMSE = 110.1 mg kg(-1)) similar to that of MCARI. These results corroborated the potential of remote sensing for assessing soil oil pollution in large areas. Traditional BMVIs are still of great value in monitoring soil oil pollution when hyperspectral data are unavailable.

  17. Soil TPH Concentration Estimation Using Vegetation Indices in an Oil Polluted Area of Eastern China

    PubMed Central

    Zhu, Linhai; Zhao, Xuechun; Lai, Liming; Wang, Jianjian; Jiang, Lianhe; Ding, Jinzhi; Liu, Nanxi; Yu, Yunjiang; Li, Junsheng; Xiao, Nengwen; Zheng, Yuanrun; Rimmington, Glyn M.

    2013-01-01

    Assessing oil pollution using traditional field-based methods over large areas is difficult and expensive. Remote sensing technologies with good spatial and temporal coverage might provide an alternative for monitoring oil pollution by recording the spectral signals of plants growing in polluted soils. Total petroleum hydrocarbon concentrations of soils and the hyperspectral canopy reflectance were measured in wetlands dominated by reeds (Phragmites australis) around oil wells that have been producing oil for approximately 10 years in the Yellow River Delta, eastern China to evaluate the potential of vegetation indices and red edge parameters to estimate soil oil pollution. The detrimental effect of oil pollution on reed communities was confirmed by the evidence that the aboveground biomass decreased from 1076.5 g m−2 to 5.3 g m−2 with increasing total petroleum hydrocarbon concentrations ranging from 9.45 mg kg−1 to 652 mg kg−1. The modified chlorophyll absorption ratio index (MCARI) best estimated soil TPH concentration among 20 vegetation indices. The linear model involving MCARI had the highest coefficient of determination (R2 = 0.73) and accuracy of prediction (RMSE = 104.2 mg kg−1). For other vegetation indices and red edge parameters, the R2 and RMSE values ranged from 0.64 to 0.71 and from 120.2 mg kg−1 to 106.8 mg kg−1 respectively. The traditional broadband normalized difference vegetation index (NDVI), one of the broadband multispectral vegetation indices (BMVIs), produced a prediction (R2 = 0.70 and RMSE = 110.1 mg kg−1) similar to that of MCARI. These results corroborated the potential of remote sensing for assessing soil oil pollution in large areas. Traditional BMVIs are still of great value in monitoring soil oil pollution when hyperspectral data are unavailable. PMID:23342066

  18. SMOG-CHAMBER TOXICOLOGY BETTER ESTIMATES THE TRUE TOXIC POTENTIAL OF ATMOSPHERIC MIXTURES

    EPA Science Inventory

    The chemistry of hazardous air pollutants (HAPs) have been studied for many years, yet little is known about how these chemicals, once interacted with urban atmospheres, affect healthy and susceptible individuals. The toxic potential of these very reactive compounds once they int...

  19. [Pollution characteristics of organic acids in atmospheric particles during haze periods in autumn in Guangzhou].

    PubMed

    Tan, Ji-hua; Zhao, Jing-ping; Duan, Jing-chun; Ma, Yong-liang; He, Ke-bin; Yang, Fu-mo

    2013-05-01

    Total suspended particles (TSP), collected during a typical haze period in Guangzhou, were analyzed for the fatty acids (C12-C30) and low molecular weight dicarboxylic acids (C3-C9) using gas chromatography/mass spectrometry (GC/MS). The results showed that the concentration of total fatty and carboxylic acids was pretty high during the haze episode. The ratios of fatty acids and carboxylic acids in haze to those in normal days were 1.9 and 2.5, respectively. During the episode of the increasing pollution, the fatty acids and carboxylic acids at night (653 ng x m(-3)) was higher than that (487 ng x m(-3)) in days. After that, the level of fatty acids and carboxylic acids in days (412 ng x m(-3)) was higher than that (336 ng x m(-3)) at night. In general, the time-series of fatty acids and carboxylic acids was similar to that of the air particle and carbonaceous species, however, the trend of the ratio of fatty acids and carboxylic acids to organic carbon was opposite to that of air particle and carbonaceous species. This ratio decreased with the increase of the concentration of air particle and after the night of 27th, the ratio increased with the decrease in the concentration of air particle. The results showed that haze pollution had a significant inhibitory effect on the enrichment of fatty and carboxylic acids. Based on the ratio of malonate to succinate (C3/C4), it could be found that primary sources contribute more to the atmospheric fatty and carboxylic acids during the autumn haze pollution periods in Guangzhou.

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

    NASA Astrophysics Data System (ADS)

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

    2016-10-01

    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.

  1. 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

  2. Extreme abundance ratios in the polluted atmosphere of the cool white dwarf NLTT 19868

    NASA Astrophysics Data System (ADS)

    Kawka, Adela; Vennes, Stéphane

    2016-05-01

    We present an analysis of intermediate-dispersion spectra and photometric data of the newly identified cool, polluted white dwarf NLTT 19868. The spectra obtained with X-shooter on the Very Large Telescope-Melipal show strong lines of calcium, and several lines of magnesium, aluminium and iron. We use these spectra and the optical-to-near-infrared spectral energy distribution to constrain the atmospheric parameters of NLTT 19868. Our analysis shows that NLTT 19868 is iron poor with respect to aluminium and calcium. A comparison with other cool, polluted white dwarfs shows that the Fe to Ca abundance ratio (Fe/Ca) varies by up to approximately two orders of magnitudes over a narrow temperature range with NLTT 19868 at one extremum in the Fe/Ca ratio and, in contrast, NLTT 888 at the other extremum. The sample shows evidence of extreme diversity in the composition of the accreted material: in the case of NLTT 888, the inferred composition of the accreted matter is akin to iron-rich planetary core composition, while in the case of NLTT 19868 it is close to mantle composition depleted by subsequent chemical separation at the bottom of the convection zone.

  3. 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.

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

    PubMed

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

    2016-10-25

    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.

  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.

  6. Comparing early twentieth century and present-day atmospheric pollution in SW France: A story of lichens.

    PubMed

    Agnan, Y; Séjalon-Delmas, N; Probst, A

    2013-01-01

    Lichens have long been known to be good indicators of air quality and atmospheric deposition. Xanthoria parietina was selected to investigate past (sourced from a herbarium) and present-day trace metal pollution in four sites from South-West France (close to Albi). Enrichment factors, relationships between elements and hierarchical classification indicated that the atmosphere was mainly impacted by coal combustion (as shown by As, Pb or Cd contamination) during the early twentieth century, whereas more recently, another mixture of pollutants (e.g. Sb, Sn, Pb and Cu) from local factories and car traffic has emerged. The Rare Earth Elements (REE) and other lithogenic elements indicated a higher dust content in the atmosphere in the early twentieth century and a specific lithological local signature. In addition to long-range atmospheric transport, local urban emissions had a strong impact on trace element contamination registered in lichens, particularly for contemporary data.

  7. [Pollution of Halogenated Polycyclic Aromatic Hydrocarbons in Atmospheric Particulate Matters of Shenzhen].

    PubMed

    Sun, Jian-lin; Chang, Wen-jing; Chen, Zheng-xia; Zeng, Hui

    2015-05-01

    Concentrations of halogenated polycyclic aromatic hydrocarbons ( HPAHs) in atmospheric PM10 and PM2.5 samples collected from Shenzhen were determined using GC-MS. Total concentrations of nine HPAHs in atmospheric PM10 and PM2.5 samples ranged from 118 to 1,476 pg · m(-3) and 89 to 407 pg · m(-3), respectively. In PM10 and PM(2.5) samples, the concentration of 9-BrAnt was the highest, followed by 7-BrBaA and 9, 10-Br2Ant. Seasonal levels of total HPAHs in atmospheric PM10 and PM2.5 samples in Shenzhen decreased in the following order: winter > autumn > spring > summer, whereas concentrations of individual HPAHs showed different seasonal levels. Meteorological conditions, including temperature, precipitation, and relative humidity, might be important factors affecting the seasonal levels of HPAHs in atmospheric PM10 and PM2.5 In addition, there were significant correlations between concentrations of HPAHs and parent PAHs. Finally, the toxic equivalency quotients (TEQs) of HPAHs were estimated. The TEQs of HPAHs in atmospheric PM10 and PM2.5 samples ranged from 17.6 to 86.2 pg · m(-3) and 14.6 to 70.4 pg · m(-3), respectively. Among individual HPAHs, 7-BrBaA contributed greatly to the total TEQs of HPAHs. Our results indicated that the total TEQs of HPAHs were lower than parent PAHs in atmospheric PM10 and PM2.5 samples in Shenzhen.

  8. [Estimation of average traffic emission factor based on synchronized incremental traffic flow and air pollutant concentration].

    PubMed

    Li, Run-Kui; Zhao, Tong; Li, Zhi-Peng; Ding, Wen-Jun; Cui, Xiao-Yong; Xu, Qun; Song, Xian-Feng

    2014-04-01

    On-road vehicle emissions have become the main source of urban air pollution and attracted broad attentions. Vehicle emission factor is a basic parameter to reflect the status of vehicle emissions, but the measured emission factor is difficult to obtain, and the simulated emission factor is not localized in China. Based on the synchronized increments of traffic flow and concentration of air pollutants in the morning rush hour period, while meteorological condition and background air pollution concentration retain relatively stable, the relationship between the increase of traffic and the increase of air pollution concentration close to a road is established. Infinite line source Gaussian dispersion model was transformed for the inversion of average vehicle emission factors. A case study was conducted on a main road in Beijing. Traffic flow, meteorological data and carbon monoxide (CO) concentration were collected to estimate average vehicle emission factors of CO. The results were compared with simulated emission factors of COPERT4 model. Results showed that the average emission factors estimated by the proposed approach and COPERT4 in August were 2.0 g x km(-1) and 1.2 g x km(-1), respectively, and in December were 5.5 g x km(-1) and 5.2 g x km(-1), respectively. The emission factors from the proposed approach and COPERT4 showed close values and similar seasonal trends. The proposed method for average emission factor estimation eliminates the disturbance of background concentrations and potentially provides real-time access to vehicle fleet emission factors.

  9. 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.

  10. Persistent organic pollutants in the Atlantic and southern oceans and oceanic atmosphere.

    PubMed

    Luek, Jenna L; Dickhut, Rebecca M; Cochran, Michele A; Falconer, Renee L; Kylin, Henrik

    2017-04-01

    Persistent organic pollutants (POPs) continue to cycle through the atmosphere and hydrosphere despite banned or severely restricted usages. Global scale analyses of POPs are challenging, but knowledge of the current distribution of these compounds is needed to understand the movement and long-term consequences of their global use. In the current study, air and seawater samples were collected Oct. 2007-Jan. 2008 aboard the Icebreaker Oden en route from Göteborg, Sweden to McMurdo Station, Antarctica. Both air and surface seawater samples consistently contained α-hexachlorocyclohexane (α-HCH), γ-HCH, hexachlorobenzene (HCB), α-Endosulfan, and polychlorinated biphenyls (PCBs). Sample concentrations for most POPs in air were higher in the northern hemisphere with the exception of HCB, which had high gas phase concentrations in the northern and southern latitudes and low concentrations near the equator. South Atlantic and Southern Ocean seawater had a high ratio of α-HCH to γ-HCH, indicating persisting levels from technical grade sources. The Atlantic and Southern Ocean continue to be net sinks for atmospheric α-, γ-HCH, and Endosulfan despite declining usage.

  11. 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.

  12. 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.

  13. 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.

  14. 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

  15. Uncertainties in BC Estimations: the Role of Atmospheric Processes

    NASA Astrophysics Data System (ADS)

    Vignati, E.; Kloster, S.; Koch, D.; Bauer, S. E.; Dentener, F.; Bond, T.; Sun, H.

    2006-12-01

    Modelling physical and chemical processes involving aerosol particles remains a large source of uncertainties. To characterize the range of uncertainty in these processes on atmospheric BC concentrations, three global models (CTM-TM5, GCM ECHAM5-HAM and GISS GCM) were run using identical BC, particulate organic matter and SO2 emission inventories provided by IIASA for the year 2000. The first two models have the same aerosol dynamic module, while TM5 is also run with a bulk aerosol scheme; the GISS model uses both bulk aerosol and a method of moments aerosol microphysical schemes. We can thus specifically assess the differences in predicted BC concentrations from using the bulk approach and the two microphysical schemes. By comparing the modeled concentrations with an extensive data set of observations, distinguished by measurement methodology, season and region, we will critically evaluate the benefit of using microphysical schemes to simulate the atmospheric BC cycle.

  16. Estimation of the efficiency of atmospheric ozone aerosol sink

    NASA Astrophysics Data System (ADS)

    Sirota, Vitaly

    1993-11-01

    The interaction of ozone with oxides occurring in aerosols (Al2O3, ZnO, MgO, TiO2) at temperatures 22 divided by -63.5 degree(s)C was provided. Laboratory experiments have shown that activity of investigated oxides with respect to ozone grows under irradiation of their surface. To calculate correctly atmospheric ozone aerosol sink one must take account of both heterogeneous processes proceeding without action of light and photocatalytic ones.

  17. Exposure and measurement contributions to estimates of acute air pollution effects.

    PubMed

    Sheppard, Lianne; Slaughter, James C; Schildcrout, Jonathan; Liu, L-J Sally; Lumley, Thomas

    2005-07-01

    Air pollution health effect studies are intended to estimate the effect of a pollutant on a health outcome. The definition of this effect depends upon the study design, disease model parameterization, and the type of analysis. Further limitations are imposed by the nature of exposure and our ability to measure it. We define a plausible exposure model for air pollutants that are relatively nonreactive and discuss how exposure varies. We discuss plausible disease models and show how their parameterizations are affected by different exposure partitions and by different study designs. We then discuss a measurement model conditional on ambient concentrations and incorporate this into the disease model. We use simulation studies to show the impact of a range of exposure model assumptions on estimation of the health effect in the ecologic time series design. This design only uses information from the time-varying ambient source exposure. When ambient and nonambient sources are independent, exposure variation due to nonambient source exposures behaves like Berkson measurement error and does not bias the effect estimates. Variation in the population attenuation of ambient concentrations over time does bias the estimates with the bias being either positive or negative depending upon the association of this parameter with ambient pollution. It is not realistic to substitute measured average personal exposures into time series studies because so much of the variation in personal exposures comes from nonambient sources that do not contribute information in the time series design. We conclude that general statements about the implications of measurement error need to be conditioned on the health effect study design and the health effect parameter to be estimated.

  18. Estimating Causal Effects of Local Air Pollution on Daily Deaths: Effect of Low Levels

    PubMed Central

    Schwartz, Joel; Bind, Marie-Abele; Koutrakis, Petros

    2016-01-01

    Background: Although many time-series studies have established associations of daily pollution variations with daily deaths, there are fewer at low concentrations, or focused on locally generated pollution, which is becoming more important as regulations reduce regional transport. Causal modeling approaches are also lacking. Objective: We used causal modeling to estimate the impact of local air pollution on mortality at low concentrations. Methods: Using an instrumental variable approach, we developed an instrument for variations in local pollution concentrations that is unlikely to be correlated with other causes of death, and examined its association with daily deaths in the Boston, Massachusetts, area. We combined height of the planetary boundary layer and wind speed, which affect concentrations of local emissions, to develop the instrument for particulate matter ≤ 2.5 μm (PM2.5), black carbon (BC), or nitrogen dioxide (NO2) variations that were independent of year, month, and temperature. We also used Granger causality to assess whether omitted variable confounding existed. Results: We estimated that an interquartile range increase in the instrument for local PM2.5 was associated with a 0.90% increase in daily deaths (95% CI: 0.25, 1.56). A similar result was found for BC, and a weaker association with NO2. The Granger test found no evidence of omitted variable confounding for the instrument. A separate test confirmed the instrument was not associated with mortality independent of pollution. Furthermore, the association remained when all days with PM2.5 concentrations > 30 μg/m3 were excluded from the analysis (0.84% increase in daily deaths; 95% CI: 0.19, 1.50). Conclusions: We conclude that there is a causal association of local air pollution with daily deaths at concentrations below U.S. EPA standards. The estimated attributable risk in Boston exceeded 1,800 deaths during the study period, indicating that important public health benefits can follow from

  19. Coupled Inertial Navigation and Flush Air Data Sensing Algorithm for Atmosphere Estimation

    NASA Technical Reports Server (NTRS)

    Karlgaard, Christopher D.; Kutty, Prasad; Schoenenberger, Mark

    2015-01-01

    This paper describes an algorithm for atmospheric state estimation that is based on a coupling between inertial navigation and flush air data sensing pressure measurements. In this approach, the full navigation state is used in the atmospheric estimation algorithm along with the pressure measurements and a model of the surface pressure distribution to directly estimate atmospheric winds and density using a nonlinear weighted least-squares algorithm. The approach uses a high fidelity model of atmosphere stored in table-look-up form, along with simplified models of that are propagated along the trajectory within the algorithm to provide prior estimates and covariances to aid the air data state solution. Thus, the method is essentially a reduced-order Kalman filter in which the inertial states are taken from the navigation solution and atmospheric states are estimated in the filter. The algorithm is applied to data from the Mars Science Laboratory entry, descent, and landing from August 2012. Reasonable estimates of the atmosphere and winds are produced by the algorithm. The observability of winds along the trajectory are examined using an index based on the discrete-time observability Gramian and the pressure measurement sensitivity matrix. The results indicate that bank reversals are responsible for adding information content to the system. The algorithm is then applied to the design of the pressure measurement system for the Mars 2020 mission. The pressure port layout is optimized to maximize the observability of atmospheric states along the trajectory. Linear covariance analysis is performed to assess estimator performance for a given pressure measurement uncertainty. The results indicate that the new tightly-coupled estimator can produce enhanced estimates of atmospheric states when compared with existing algorithms.

  20. Effect of geocoding errors on traffic-related air pollutant exposure and concentration estimates

    PubMed Central

    Ganguly, Rajiv; Batterman, Stuart; Isakov, Vlad; Snyder, Michelle; Breen, Michael; Brakefield-Caldwell, Wilma

    2015-01-01

    Exposure to traffic-related air pollutants is highest very near roads, and thus exposure estimates are sensitive to positional errors. This study evaluates positional and PM2.5 concentration errors that result from the use of automated geocoding methods and from linearized approximations of roads in link-based emission inventories. Two automated geocoders (Bing Map and ArcGIS) along with handheld GPS instruments were used to geocode 160 home locations of children enrolled in an air pollution study investigating effects of traffic-related pollutants in Detroit, Michigan. The average and maximum positional errors using the automated geocoders were 35 and 196 m, respectively. Comparing road edge and road centerline, differences in house-to-highway distances averaged 23 m and reached 82 m. These differences were attributable to road curvature, road width and the presence of ramps, factors that should be considered in proximity measures used either directly as an exposure metric or as inputs to dispersion or other models. Effects of positional errors for the 160 homes on PM2.5 concentrations resulting from traffic-related emissions were predicted using a detailed road network and the RLINE dispersion model. Concentration errors averaged only 9%, but maximum errors reached 54% for annual averages and 87% for maximum 24-h averages. Whereas most geocoding errors appear modest in magnitude, 5% to 20% of residences are expected to have positional errors exceeding 100 m. Such errors can substantially alter exposure estimates near roads because of the dramatic spatial gradients of traffic-related pollutant concentrations. To ensure the accuracy of exposure estimates for traffic-related air pollutants, especially near roads, confirmation of geocoordinates is recommended. PMID:25670023

  1. Effect of geocoding errors on traffic-related air pollutant exposure and concentration estimates.

    PubMed

    Ganguly, Rajiv; Batterman, Stuart; Isakov, Vlad; Snyder, Michelle; Breen, Michael; Brakefield-Caldwell, Wilma

    2015-01-01

    Exposure to traffic-related air pollutants is highest very near roads, and thus exposure estimates are sensitive to positional errors. This study evaluates positional and PM2.5 concentration errors that result from the use of automated geocoding methods and from linearized approximations of roads in link-based emission inventories. Two automated geocoders (Bing Map and ArcGIS) along with handheld GPS instruments were used to geocode 160 home locations of children enrolled in an air pollution study investigating effects of traffic-related pollutants in Detroit, Michigan. The average and maximum positional errors using the automated geocoders were 35 and 196 m, respectively. Comparing road edge and road centerline, differences in house-to-highway distances averaged 23 m and reached 82 m. These differences were attributable to road curvature, road width and the presence of ramps, factors that should be considered in proximity measures used either directly as an exposure metric or as inputs to dispersion or other models. Effects of positional errors for the 160 homes on PM2.5 concentrations resulting from traffic-related emissions were predicted using a detailed road network and the RLINE dispersion model. Concentration errors averaged only 9%, but maximum errors reached 54% for annual averages and 87% for maximum 24-h averages. Whereas most geocoding errors appear modest in magnitude, 5% to 20% of residences are expected to have positional errors exceeding 100 m. Such errors can substantially alter exposure estimates near roads because of the dramatic spatial gradients of traffic-related pollutant concentrations. To ensure the accuracy of exposure estimates for traffic-related air pollutants, especially near roads, confirmation of geocoordinates is recommended.

  2. Applicability of Fluorescence and Absorbance Spectroscopy to Estimate Organic Pollution in Rivers.

    PubMed

    Knapik, Heloise Garcia; Fernandes, Cristovão Vicente Scapulatempo; de Azevedo, Júlio Cesar Rodrigues; do Amaral Porto, Monica Ferreira

    2014-12-01

    This article explores the applicability of fluorescence and absorbance spectroscopy for estimating organic pollution in polluted rivers. The relationship between absorbance, fluorescence intensity, dissolved organic carbon, biochemical oxygen demand (BOD), chemical oxygen demand (COD), and other water quality parameters were used to characterize and identify the origin and the spatial variability of the organic pollution in a highly polluted watershed. Analyses were performed for the Iguassu River, located in southern Brazil, with area about 2,700 km(2) and ∼3 million inhabitants. Samples were collect at six monitoring sites covering 107 km of the main river. BOD, COD, nitrogen, and phosphorus concentration indicates a high input of sewage to the river. Specific absorbance at 254 and 285 nm (SUVA254 and A285/COD) did not show significant variation between sites monitored, indicating the presence of both dissolved compounds found in domestic effluents and humic and fulvic compounds derived from allochthonous organic matter. Correlations between BOD and tryptophan-like fluorescence peak (peak T2, r=0.7560, and peak T1, r=0.6949) and tyrosine-like fluorescence peak (peak B, r=0.7321) indicated the presence of labile organic matter and thus confirmed the presence of sewage in the river. Results showed that fluorescence and absorbance spectroscopy provide useful information on pollution in rivers from critical watersheds and together are a robust method that is simpler and more rapid than traditional methods employed by regulatory agencies.

  3. Measurement error in mobile source air pollution exposure estimates due to residential mobility during pregnancy.

    PubMed

    Pennington, Audrey Flak; Strickland, Matthew J; Klein, Mitchel; Zhai, Xinxin; Russell, Armistead G; Hansen, Craig; Darrow, Lyndsey A

    2016-12-14

    Prenatal air pollution exposure is frequently estimated using maternal residential location at the time of delivery as a proxy for residence during pregnancy. We describe residential mobility during pregnancy among 19,951 children from the Kaiser Air Pollution and Pediatric Asthma Study, quantify measurement error in spatially resolved estimates of prenatal exposure to mobile source fine particulate matter (PM2.5) due to ignoring this mobility, and simulate the impact of this error on estimates of epidemiologic associations. Two exposure estimates were compared, one calculated using complete residential histories during pregnancy (weighted average based on time spent at each address) and the second calculated using only residence at birth. Estimates were computed using annual averages of primary PM2.5 from traffic emissions modeled using a Research LINE-source dispersion model for near-surface releases (RLINE) at 250 m resolution. In this cohort, 18.6% of children were born to mothers who moved at least once during pregnancy. Mobile source PM2.5 exposure estimates calculated using complete residential histories during pregnancy and only residence at birth were highly correlated (rS>0.9). Simulations indicated that ignoring residential mobility resulted in modest bias of epidemiologic associations toward the null, but varied by maternal characteristics and prenatal exposure windows of interest (ranging from -2% to -10% bias).Journal of Exposure Science and Environmental Epidemiology advance online publication, 14 December 2016; doi:10.1038/jes.2016.66.

  4. Analysis of observations and results of numerical modeling of meteorological parameters and atmospheric air pollution under weak wind conditions in the city of Tomsk

    NASA Astrophysics Data System (ADS)

    Starchenko, Alexander V.; Bart, Andrey A.; Kizhner, Lyubov I.; Barashkova, Nadezhda K.; Volkova, Marina A.; Zhuravlev, Georgi G.; Kuzhevskaya, Irina V.; Terenteva, Maria V.

    2015-11-01

    The results of calculation of meteorological parameters using a meteorological model, TSU-NM3, as well as prediction of some indices of atmospheric air pollution in the city of Tomsk obtained from a mesoscale photochemical model are presented. The calculation results are compared with observational data on the atmosphere and pollutants.

  5. Estimating spatial veriability in atmospheric properties over remotely sensed land-surface conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper investigates the spatial relationships between land-surface fluxes and near-surface atmospheric properties (AP), and the potential errors in flux estimation due to homogeneous atmospheric inputs over heterogeneous landscapes. A Large Eddy Simulation (LES) model is coupled to a surface ene...

  6. 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

  7. 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.

  8. Stellar atmospheric parameter estimation using Gaussian process regression

    NASA Astrophysics Data System (ADS)

    Bu, Yude; Pan, Jingchang

    2015-02-01

    As is well known, it is necessary to derive stellar parameters from massive amounts of spectral data automatically and efficiently. However, in traditional automatic methods such as artificial neural networks (ANNs) and kernel regression (KR), it is often difficult to optimize the algorithm structure and determine the optimal algorithm parameters. Gaussian process regression (GPR) is a recently developed method that has been proven to be capable of overcoming these difficulties. Here we apply GPR to derive stellar atmospheric parameters from spectra. Through evaluating the performance of GPR on Sloan Digital Sky Survey (SDSS) spectra, Medium resolution Isaac Newton Telescope Library of Empirical Spectra (MILES) spectra, ELODIE spectra and the spectra of member stars of galactic globular clusters, we conclude that GPR can derive stellar parameters accurately and precisely, especially when we use data preprocessed with principal component analysis (PCA). We then compare the performance of GPR with that of several widely used regression methods (ANNs, support-vector regression and KR) and find that with GPR it is easier to optimize structures and parameters and more efficient and accurate to extract atmospheric parameters.

  9. Modelling the atmospheric boundary layer for remotely sensed estimates of daily evaporation

    NASA Technical Reports Server (NTRS)

    Gurney, R. J.; Blyth, K.; Camillo, P. J.

    1984-01-01

    An energy and moisture balance model of the soil surface was used to estimate daily evaporation from wheat and barley fields in West Germany. The model was calibrated using remotely sensed surface temperature estimates. Complete atmospheric boundary layer models are difficult to use because of the number of parameters involved and a simplified model was used here. The resultant evaporation estimates were compared to eddy correlation evaporation estimates and good agreement was found.

  10. Agriculture Crop Burning in Northwestern India and Its Impact on Atmospheric Pollution and Air Quality

    NASA Astrophysics Data System (ADS)

    Singh, R. P.; Chauhan, A.; Gonzalez Abad, G.

    2014-12-01

    Crop burning season, over northern India, occurs during October-November and April-May after harvesting season. The mechanized harvesting started in 1986, and every year crop residues are burnt in the northwestern parts of India. During post-monsoon season, October - November, the boundary layer is shallow; as a result the crop burning greatly impacts the regional air quality and climate of the northern parts of south Asia. Due to intense burning episodes, heavy smoke pollution-laden plumes are transported all along the Indo-Gangetic basin in the northern parts of India, depending upon diurnal changes in the wind patterns. We find that, in general, the dominant westerly winds transport the plumes and emissions far away from the source region up to the eastern parts of Indo-Gangetic basin, further dispersing over central India to the south. We use retrievals of formaldehyde and nitrogen dioxide and Aerosol Index from the Ozone Monitoring Instrument (OMI) onboard NASA Aura satellite together with Moderate Resolution Imaging Spectroradiometer (MODIS) onboard NASA Terra and Aqua fire counts to assess the seasonal variation and geographical extent of the emissions due to burning of crop residues. In addition, our results, based on satellite measurements, indicate that the smoke plumes and biomass burning emissions are also transported over the Himalayan region and beyond, resulting in enhanced concentrations of aerosol loading and trace gases. Overall, our findings suggest that, during post-monsoon season, crop burning smoke plumes and emissions are the main cause of poor air quality, high atmospheric pollution and dense haze/smog, especially in the Indo-Gangetic basin.

  11. Quantifying the uncertainties of a bottom-up emission inventory of anthropogenic atmospheric pollutants in China

    NASA Astrophysics Data System (ADS)

    Zhao, Y.; Nielsen, C. P.; Lei, Y.; McElroy, M. B.; Hao, J.

    2011-03-01

    studies, the results are not always consistent with those derived from satellite observations. The results thus represent an incremental research advance; while the analysis provides current estimates of uncertainty to researchers investigating Chinese and global atmospheric transport and chemistry, it also identifies specific needs in data collection and analysis to improve on them. Strengthened quantification of emissions of the included species and other, closely associated ones - notably CO2, generated largely by the same processes and thus subject to many of the same parameter uncertainties - is essential not only for science but for the design of policies to redress critical atmospheric environmental hazards at local, regional, and global scales.

  12. Quantifying the uncertainties of a bottom-up emission inventory of anthropogenic atmospheric pollutants in China

    NASA Astrophysics Data System (ADS)

    Zhao, Y.; Nielsen, C. P.; Lei, Y.; McElroy, M. B.; Hao, J.

    2010-11-01

    studies, the results are not always consistent with those derived from satellite observations. The results thus represent an incremental research advance; while the analysis provides current estimates of uncertainty to researchers investigating Chinese and global atmospheric transport and chemistry, it also identifies specific needs in data collection and analysis to improve on them. Strengthened quantification of emissions of the included species and other, closely associated ones - notably CO2, generated largely by the same processes and thus subject to many of the same parameter uncertainties - is essential not only for science but for the design of policies to redress critical atmospheric environmental hazards at local, regional, and global scales.

  13. [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

  14. 60 years of UK visibility measurements: impact of meteorology and atmospheric pollutants on visibility

    NASA Astrophysics Data System (ADS)

    Singh, Ajit; Bloss, William J.; Pope, Francis D.

    2017-02-01

    Reduced visibility is an indicator of poor air quality. Moreover, degradation in visibility can be hazardous to human safety; for example, low visibility can lead to road, rail, sea and air accidents. In this paper, we explore the combined influence of atmospheric aerosol particle and gas characteristics, and meteorology, on long-term visibility. We use visibility data from eight meteorological stations, situated in the UK, which have been running since the 1950s. The site locations include urban, rural and marine environments. Most stations show a long-term trend of increasing visibility, which is indicative of reductions in air pollution, especially in urban areas. Additionally, the visibility at all sites shows a very clear dependence on relative humidity, indicating the importance of aerosol hygroscopicity on the ability of aerosol particles to scatter radiation. The dependence of visibility on other meteorological parameters, such as wind speed and wind direction, is also investigated. Most stations show long-term increases in temperature which can be ascribed to climate change, land-use changes (e.g. urban heat island effects) or a combination of both; the observed effect is greatest in urban areas. The impact of this temperature change upon local relative humidity is discussed. To explain the long-term visibility trends and their dependence on meteorological conditions, the measured data were fitted to a newly developed light-extinction model to generate predictions of historic aerosol and gas scattering and absorbing properties. In general, an excellent fit was achieved between measured and modelled visibility for all eight sites. The model incorporates parameterizations of aerosol hygroscopicity, particle concentration, particle scattering, and particle and gas absorption. This new model should be applicable and is easily transferrable to other data sets worldwide. Hence, historical visibility data can be used to assess trends in aerosol particle

  15. Error estimations of dry deposition velocities of air pollutants using bulk sea surface temperature under common assumptions

    NASA Astrophysics Data System (ADS)

    Lan, Yung-Yao; Tsuang, Ben-Jei; Keenlyside, Noel; Wang, Shu-Lun; Arthur Chen, Chen-Tung; Wang, Bin-Jye; Liu, Tsun-Hsien

    2010-07-01

    It is well known that skin sea surface temperature (SSST) is different from bulk sea surface temperature (BSST) by a few tenths of a degree Celsius. However, the extent of the error associated with dry deposition (or uptake) estimation by using BSST is not well known. This study tries to conduct such an evaluation using the on-board observation data over the South China Sea in the summers of 2004 and 2006. It was found that when a warm layer occurred, the deposition velocities using BSST were underestimated within the range of 0.8-4.3%, and the absorbed sea surface heat flux was overestimated by 21 W m -2. In contrast, under cool skin only conditions, the deposition velocities using BSST were overestimated within the range of 0.5-2.0%, varying with pollutants and the absorbed sea surface heat flux was underestimated also by 21 W m -2. Scale analysis shows that for a slightly soluble gas (e.g., NO 2, NO and CO), the error in the solubility estimation using BSST is the major source of the error in dry deposition estimation. For a highly soluble gas (e.g., SO 2), the error in the estimation of turbulent heat fluxes and, consequently, aerodynamic resistance and gas-phase film resistance using BSST is the major source of the total error. In contrast, for a medium soluble gas (e.g., O 3 and CO 2) both the errors from the estimations of the solubility and aerodynamic resistance are important. In addition, deposition estimations using various assumptions are discussed. The largest uncertainty is from the parameterizations for chemical enhancement factors. Other important areas of uncertainty include: (1) various parameterizations for gas-transfer velocity; (2) neutral-atmosphere assumption; (3) using BSST as SST, and (4) constant pH value assumption.

  16. Time and space variability of spectral estimates of atmospheric pressure

    NASA Technical Reports Server (NTRS)

    Canavero, Flavio G.; Einaudi, Franco

    1987-01-01

    The temporal and spatial behaviors of atmospheric pressure spectra over the northern Italy and the Alpine massif were analyzed using data on surface pressure measurements carried out at two microbarograph stations in the Po Valley, one 50 km south of the Alps, the other in the foothills of the Dolomites. The first 15 days of the study overlapped with the Alpex Intensive Observation Period. The pressure records were found to be intrinsically nonstationary and were found to display substantial time variability, implying that the statistical moments depend on time. The shape and the energy content of spectra depended on different time segments. In addition, important differences existed between spectra obtained at the two stations, indicating a substantial effect of topography, particularly for periods less than 40 min.

  17. Patterns in atmospheric carbonaceous aerosols in China: emission estimates and observed concentrations

    NASA Astrophysics Data System (ADS)

    Cui, H.; Mao, P.; Zhao, Y.; Nielsen, C. P.; Zhang, J.

    2015-08-01

    China is experiencing severe carbonaceous aerosol pollution driven mainly by large emissions resulting from intensive use of solid fuels. To gain a better understanding of the levels and trends of carbonaceous aerosol emissions and the resulting ambient concentrations at the national scale, we update an emission inventory of anthropogenic organic carbon (OC) and elemental carbon (EC) and employ existing observational studies to analyze characteristics of these aerosols including temporal, spatial, and size distributions, and the levels and shares of secondary organic carbon (SOC) in total OC. We further use ground observations to test the levels and inter-annual trends of the calculated national and provincial emissions of carbonaceous aerosols, and propose possible improvements in emission estimation for the future. The national OC emissions are estimated to have increased 29 % from 2000 (2127 Gg) to 2012 (2749 Gg) and EC by 37 % (from 1356 to 1857 Gg). The residential, industrial, and transportation sectors contributed an estimated 74-78, 17-21, and 4-6 % of the total emissions of OC, respectively, and 49-55, 30-34, and 14-18 % of EC. Updated emission factors (EFs) based on the most recent local field measurements, particularly for biofuel stoves, led to considerably lower emissions of OC compared to previous inventories. Compiling observational data across the country, higher concentrations of OC and EC are found in northern and inland cities, while higher OC / EC ratios are found in southern sites, due to the joint effects of primary emissions and meteorology. Higher OC / EC ratios are estimated at rural and remote sites compared to urban ones, attributed to more emissions of OC from biofuel use, more biogenic emissions of volatile organic compound (VOC) precursors to SOC, and/or transport of aged aerosols. For most sites, higher concentrations of OC, EC, and SOC are observed in colder seasons, while SOC / OC is reduced, particularly at rural and remote sites

  18. Patterns in atmospheric carbonaceous aerosols in China: emission estimates and observed concentrations

    NASA Astrophysics Data System (ADS)

    Cui, H.; Mao, P.; Zhao, Y.; Nielsen, C. P.; Zhang, J.

    2015-03-01

    China is experiencing severe carbonaceous aerosol pollution driven mainly by large emissions resulting from intensive use of solid fuels. To gain a better understanding of the levels and trends of carbonaceous aerosol emissions and the resulting ambient concentrations at the national scale, we update an emission inventory of anthropogenic organic carbon (OC) and elemental carbon (EC) and employ existing observational studies to analyze characteristics of these aerosols including temporal, spatial, and size distributions, and the levels and shares of secondary organic carbon (SOC) in total OC. We further use ground observations to test the levels and inter-annual trends of the calculated national and provincial emissions of carbonaceous aerosols, and propose possible improvements in emission estimation for the future. The national OC emissions are estimated to have increased 29% from 2000 (2127 Gg) to 2012 (2749 Gg) and EC by 37% (from 1356 to 1857 Gg). The residential, industrial, and transportation sectors contributed an estimated 76 ± 2, 19 ± 2 and 5 ± 1% of the total emissions of OC, respectively, and 52 ± 3, 32 ± 2 and 16 ± 2% of EC. Updated emission factors based on the most recent local field measurements, particularly for biofuel stoves, lead to considerably lower emissions of OC compared to previous inventories. Compiling observational data across the country, higher concentrations of OC and EC are found in northern and inland cities, while larger OC/EC and SOC/OC ratios are found in southern cities, due to the joint effects of primary emissions and meteorology. Higher SOC/OC ratios are estimated at rural and remote sites compared to urban ones, attributed to more emissions of OC from biofuel use, more biogenic emissions of volatile organic compound (VOC) precursors to SOC, and/or transport of aged aerosols. For most sites, higher concentrations of OC, EC, and SOC are observed in colder seasons, while SOC/OC is reduced, particularly at rural and

  19. Prenatal exposure to airborne polycyclic aromatic hydrocarbons and IQ: estimated benefit of pollution reduction.

    PubMed

    Perera, Frederica; Weiland, Katherine; Neidell, Matthew; Wang, Shuang

    2014-08-01

    Outdoor air pollution, largely from fossil fuel burning, is a major cause of morbidity and mortality in the United States, costing billions of dollars every year in health care and loss of productivity. The developing fetus and young child are especially vulnerable to neurotoxicants, such as polycyclic aromatic hydrocarbons (PAH) released to ambient air by combustion of fossil fuel and other organic material. Low-income populations are disproportionately exposed to air pollution. On the basis of the results of a prospective cohort study in a low-income population in New York City (NYC) that found a significant inverse association between child IQ and prenatal exposure to airborne PAH, we estimated the increase in IQ and related lifetime earnings in a low-income urban population as a result of a hypothesized modest reduction of ambient PAH concentrations in NYC of 0.25 ng/m(3). For reference, the current estimated annual mean PAH concentration is ~1 ng/m(3). Restricting to NYC Medicaid births and using a 5 per cent discount rate, we estimated the gain in lifetime earnings due to IQ increase for a single year cohort to be US$215 million (best estimate). Using much more conservative assumptions, the estimate was $43 million. This analysis suggests that a modest reduction in ambient concentrations of PAH is associated with substantial economic benefits to children.

  20. Increased estimates of air-pollution emissions from Brazilian sugar-cane ethanol

    NASA Astrophysics Data System (ADS)

    Tsao, C.-C.; Campbell, J. E.; Mena-Carrasco, M.; Spak, S. N.; Carmichael, G. R.; Chen, Y.

    2012-01-01

    Accelerating biofuel production has been promoted as an opportunity to enhance energy security, offset greenhouse-gas emissions and support rural economies. However, large uncertainties remain in the impacts of biofuels on air quality and climate. Sugar-cane ethanol is one of the most widely used biofuels, and Brazil is its largest producer. Here we use a life-cycle approach to produce spatially and temporally explicit estimates of air-pollutant emissions over the whole life cycle of sugar-cane ethanol in Brazil. We show that even in regions where pre-harvest field burning has been eliminated on half the croplands, regional emissions of air pollutants continue to increase owing to the expansion of sugar-cane growing areas, and burning continues to be the dominant life-cycle stage for emissions. Comparison of our estimates of burning-phase emissions with satellite estimates of burning in São Paulo state suggests that sugar-cane field burning is not fully accounted for in satellite-based inventories, owing to the small spatial scale of individual fires. Accounting for this effect leads to revised regional estimates of burned area that are four times greater than some previous estimates. Our revised emissions maps thus suggest that biofuels may have larger impacts on regional climate forcing and human health than previously thought.

  1. 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.

  2. Fast single image haze removal via local atmospheric light veil estimation

    PubMed Central

    Sun, Wei; Wang, Hao; Sun, Changhao; Guo, Baolong; Jia, Wenyan; Sun, Mingui

    2015-01-01

    In this study, a novel single-image based dehazing framework is proposed to remove haze artifacts from images through local atmospheric light estimation. We use a novel strategy based on a physical model where the extreme intensity of each RGB pixel is used to define an initial atmospheric veil (local atmospheric light veil). Across bilateral filter is applied to each veil to achieve both local smoothness and edge preservation. A transmission map and a reflection component of each RGB channel are constructed from the physical atmospheric scattering model. The proposed approach avoids adverse effects caused by the error in estimating the global atmospheric light. Experimental results on outdoor hazy images demonstrate that the proposed method produces image output with satisfactory visual quality and color fidelity. Our comparative study demonstrates a higher performance of our method over several state-of-the-art methods. PMID:26744548

  3. 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.

  4. Individual exposure estimates may be erroneous when spatiotemporal variability of air pollution and human mobility are ignored.

    PubMed

    Park, Yoo Min; Kwan, Mei-Po

    2017-01-01

    This study aims to empirically demonstrate the necessity to consider both the spatiotemporal variability of air pollution and individual daily movement patterns in exposure and health risk assessment. It compares four different types of exposure estimates generated by using (1) individual movement data and hourly air pollution concentrations; (2) individual movement data and daily average air pollution data; (3) residential location and hourly pollution levels; and (4) residential location and daily average pollution data. These four estimates are significantly different, which supports the argument that ignoring the spatiotemporal variability of environmental risk factors and human mobility may lead to misleading results in exposure assessment. Additionally, three-dimensional (3D) geovisualization presented in the paper shows how person-specific space-time context is generated by the interactions between air pollution and an individual, and how the different individualized contexts place individuals at different levels of health risk.

  5. Establishment of a database of emission factors for atmospheric pollutants from Chinese coal-fired power plants

    NASA Astrophysics Data System (ADS)

    Zhao, Yu; Wang, Shuxiao; Nielsen, Chris P.; Li, Xinghua; Hao, Jiming

    2010-04-01

    Field measurements and data investigations were conducted for developing an emission factor database for inventories of atmospheric pollutants from Chinese coal-fired power plants. Gaseous pollutants and particulate matter (PM) of different size fractions were measured using a gas analyzer and an electric low-pressure impactor (ELPI), respectively, for ten units in eight coal-fired power plants across the country. Combining results of field tests and literature surveys, emission factors with 95% confidence intervals (CIs) were calculated by boiler type, fuel quality, and emission control devices using bootstrap and Monte Carlo simulations. The emission factor of uncontrolled SO 2 from pulverized combustion (PC) boilers burning bituminous or anthracite coal was estimated to be 18.0S kg t -1 (i.e., 18.0 × the percentage sulfur content of coal, S) with a 95% CI of 17.2S-18.5S. NO X emission factors for pulverized-coal boilers ranged from 4.0 to 11.2 kg t -1, with uncertainties of 14-45% for different unit types. The emission factors of uncontrolled PM 2.5, PM 10, and total PM emitted by PC boilers were estimated to be 0.4A (where A is the percentage ash content of coal), 1.5A and 6.9A kg t -1, respectively, with 95% CIs of 0.3A-0.5A, 1.1A-1.9A and 5.8A-7.9A. The analogous PM values for emissions with electrostatic precipitator (ESP) controls were 0.032A (95% CI: 0.021A-0.046A), 0.065A (0.039A-0.092A) and 0.094A (0.0656A-0.132A) kg t -1, and 0.0147A (0.0092-0.0225A), 0.0210A (0.0129A-0.0317A), and 0.0231A (0.0142A-0.0348A) for those with both ESP and wet flue-gas desulfurization (wet-FGD). SO 2 and NO X emission factors for Chinese power plants were smaller than those of U.S. EPA AP-42 database, due mainly to lower heating values of coals in China. PM emission factors for units with ESP, however, were generally larger than AP-42 values, because of poorer removal efficiencies of Chinese dust collectors. For units with advanced emission control technologies, more field

  6. A Vertical Diffusion Scheme to estimate the atmospheric rectifier effect

    NASA Astrophysics Data System (ADS)

    Chen, Baozhang; Chen, Jing M.; Liu, Jane; Chan, Douglas; Higuchi, Kaz; Shashkov, Alexander

    2004-02-01

    The magnitude and spatial distribution of the carbon sink in the extratropical Northern Hemisphere remain uncertain in spite of much progress made in recent decades. Vertical CO2 diffusion in the planetary boundary layer (PBL) is an integral part of atmospheric CO2 transport and is important in understanding the global CO2 distribution pattern, in particular, the rectifier effect on the distribution [Keeling et al., 1989; Denning et al., 1995]. Attempts to constrain carbon fluxes using surface measurements and inversion models are limited by large uncertainties in this effect governed by different processes. In this study, we developed a Vertical Diffusion Scheme (VDS) to investigate the vertical CO2 transport in the PBL and to evaluate CO2 vertical rectification. The VDS was driven by the net ecosystem carbon flux and the surface sensible heat flux, simulated using the Boreal Ecosystem Productivity Simulator (BEPS) and a land surface scheme. The VDS model was validated against half-hourly CO2 concentration measurements at 20 m and 40 m heights above a boreal forest, at Fraserdale (49°52'29.9''N, 81°34'12.3''W), Ontario, Canada. The amplitude and phase of the diurnal/seasonal cycles of simulated CO2 concentration during the growing season agreed closely with the measurements (linear correlation coefficient (R) equals 0.81). Simulated vertical and temporal distribution patterns of CO2 concentration were comparable to those measured at the North Carolina tower. The rectifier effect, in terms of an annual-mean vertical gradient of CO2 concentration in the atmosphere that decreases from the surface to the top of PBL, was found at Fraserdale to be about 3.56 ppmv. Positive covariance between the seasonal cycles of plant growth and PBL vertical diffusion was responsible for about 75% of the effect, and the rest was caused by covariance between their diurnal cycles. The rectifier effect exhibited strong seasonal variations, and the contribution from the diurnal cycle

  7. Air pollution from gas flaring: new emission factor estimates and detection in a West African aerosol remote-sensing climatology

    NASA Astrophysics Data System (ADS)

    MacKenzie, Rob; Fawole, Olusegun Gabriel; Levine, James; Cai, Xiaoming

    2016-04-01

    Gas flaring, the disposal of gas through stacks in an open-air flame, is a common feature in the processing of crude oil, especially in oil-rich regions of the world. Gas flaring is a prominent source of volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAH), CO, CO2, nitrogen oxides (NOx), SO2 (in "sour" gas only), and soot (black carbon), as well as the release of locally significant amounts of heat. The rates of emission of these pollutants from gas flaring depend on a number of factors including, but not limited to, fuel composition and quantity, stack geometry, flame/combustion characteristics, and prevailing meteorological conditions. Here, we derive new estimated emission factors (EFs) for carbon-containing pollutants (excluding PAH). The air pollution dispersion model, ADMS5, is used to simulate the dispersion of the pollutants from flaring stacks in the Niger delta. A seasonal variation of the dispersion pattern of the pollutant within a year is studied in relation to the movements of the West Africa Monsoon (WAM) and other prevailing meteorological factors. Further, we have clustered AERONET aerosol signals using trajectory analysis to identify dominant aerosol sources at the Ilorin site in West Africa (4.34 oE, 8.32 oN). A 10-year trajectory-based analysis was undertaken (2005-2015, excluding 2010). Of particular interest are air masses that have passed through the gas flaring region in the Niger Delta area en-route the AERONET site. 7-day back trajectories were calculated using the UK Universities Global Atmospheric Modelling Programme (UGAMP) trajectory model which is driven by analyses from the European Centre for Medium-Range Weather Forecasts (ECMWF). From the back-trajectory calculations, dominant sources are identified, using literature classifications: desert dust (DD); Biomass burning (BB); and Urban-Industrial (UI). We use a combination of synoptic trajectories and aerosol optical properties to distinguish a fourth source

  8. CO2 flux estimation errors associated with moist atmospheric processes

    NASA Astrophysics Data System (ADS)

    Parazoo, N. C.; Denning, A. S.; Kawa, S. R.; Pawson, S.; Lokupitiya, R.

    2012-04-01

    Vertical transport by moist sub-grid scale processes such as deep convection is a well-known source of uncertainty in CO2 source/sink inversion. However, a dynamical link between moist transport, satellite CO2 retrievals, and source/sink inversion has not yet been established. Here we examine the effect of moist processes on (1) synoptic CO2 transport by Version-4 and Version-5 NASA Goddard Earth Observing System Data Assimilation System (NASA-DAS) meteorological analyses, and (2) source/sink inversion. We find that synoptic transport processes, such as fronts and dry/moist conveyors, feed off background vertical CO2 gradients, which are modulated by sub-grid vertical transport. The implication for source/sink estimation is two-fold. First, CO2 variations contained in moist poleward moving air masses are systematically different from variations in dry equatorward moving air. Moist poleward transport is hidden from orbital sensors on satellites, causing a sampling bias, which leads directly to continental scale source/sink estimation errors of up to 0.25 PgC yr-1 in northern mid-latitudes. Second, moist processes are represented differently in GEOS-4 and GEOS-5, leading to differences in vertical CO2 gradients, moist poleward and dry equatorward CO2 transport, and therefore the fraction of CO2 variations hidden in moist air from satellites. As a result, sampling biases are amplified, causing source/sink estimation errors of up to 0.55 PgC yr-1 in northern mid-latitudes. These results, cast from the perspective of moist frontal transport processes, support previous arguments that the vertical gradient of CO2 is a major source of uncertainty in source/sink inversion.

  9. 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.

  10. Awareness of bad news, environmental attitudes, and subjective estimates of coastal pollution

    SciTech Connect

    Eiser, J.R.; Reicher, S.D.; Podpadec, T.J. )

    1994-12-01

    Questionnaires distributed to 154 holiday-makers on beaches in Southwest England assessed awareness of local hazards or incidents associated with either the electricity supply industry or the water and sewage industry and examined the relationship between awareness and evaluations of the industry, current and future levels of pollution on the beach in question, and general levels of concern about environmental pollution. With respect to electricity, those respondents who were more aware of reports claiming a higher incidence of childhood leukemia in the vicinity of a nearby nuclear plant evaluated the electricity industry as less competent or trustworthy, showed higher levels of environmental concern, and were more pessimistic in their estimates of present and future levels of specific pollutants on their beach. With respect to the water industry, similar effects were associated with greater awareness of an accident at a water treatment plant and agricultural pollution of a nearby estuary. These findings are interpreted as suggesting a cyclical relationship between risk awareness and concern. On the one hand, reports about environmental hazards may lead to generalized concern across specific contexts; on the other hand, greater levels of concern may sensitize individuals to such reports. 10 refs., 1 tab.

  11. [Applying temporally-adjusted land use regression models to estimate ambient air pollution exposure during pregnancy].

    PubMed

    Zhang, Y J; Xue, F X; Bai, Z P

    2017-03-06

    The impact of maternal air pollution exposure on offspring health has received much attention. Precise and feasible exposure estimation is particularly important for clarifying exposure-response relationships and reducing heterogeneity among studies. Temporally-adjusted land use regression (LUR) models are exposure assessment methods developed in recent years that have the advantage of having high spatial-temporal resolution. Studies on the health effects of outdoor air pollution exposure during pregnancy have been increasingly carried out using this model. In China, research applying LUR models was done mostly at the model construction stage, and findings from related epidemiological studies were rarely reported. In this paper, the sources of heterogeneity and research progress of meta-analysis research on the associations between air pollution and adverse pregnancy outcomes were analyzed. The methods of the characteristics of temporally-adjusted LUR models were introduced. The current epidemiological studies on adverse pregnancy outcomes that applied this model were systematically summarized. Recommendations for the development and application of LUR models in China are presented. This will encourage the implementation of more valid exposure predictions during pregnancy in large-scale epidemiological studies on the health effects of air pollution in China.

  12. Using optimal estimation method for upper atmospheric Lidar temperature retrieval

    NASA Astrophysics Data System (ADS)

    Zou, Rongshi; Pan, Weilin; Qiao, Shuai

    2016-07-01

    Conventional ground based Rayleigh lidar temperature retrieval use integrate technique, which has limitations that necessitate abandoning temperatures retrieved at the greatest heights due to the assumption of a seeding value required to initialize the integration at the highest altitude. Here we suggests the use of a method that can incorporate information from various sources to improve the quality of the retrieval result. This approach inverts lidar equation via optimal estimation method(OEM) based on Bayesian theory together with Gaussian statistical model. It presents many advantages over the conventional ones: 1) the possibility of incorporating information from multiple heterogeneous sources; 2) provides diagnostic information about retrieval qualities; 3) ability of determining vertical resolution and maximum height to which the retrieval is mostly independent of the a priori profile. This paper compares one-hour temperature profiles retrieved using conventional and optimal estimation methods at Golmud, Qinghai province, China. Results show that OEM results show a better agreement with SABER profile compared with conventional one, in some region it is much lower than SABER profile, which is a very different results compared with previous studies, further studies are needed to explain this phenomenon. The success of applying OEM on temperature retrieval is a validation for using as retrieval framework in large synthetic observation systems including various active remote sensing instruments by incorporating all available measurement information into the model and analyze groups of measurements simultaneously to improve the results.

  13. Estimates of the atmospheric deposition of sulfur and nitrogen species: Clean Air Status and Trends Network 1990-2000.

    PubMed

    Baumgardner, Ralph E; Lavery, Thomas F; Rogers, Christopher M; Isil, Selma S

    2002-06-15

    The Clean Air Status and Trends Network (CASTNet) was established by the U.S. EPA in response to the requirements of the 1990 Clean Air Act Amendments. To satisfy these requirements CASTNet was designed to assess and report on geographic patterns and long-term, temporal trends in ambient air pollution and acid deposition in order to gauge the effectiveness of current and future mandated emission reductions. This paper presents an analysis of the spatial patterns of deposition of sulfur and nitrogen pollutants for the period 1990-2000. Estimates of deposition are provided for two 4-yr periods: 1990-1993 and 1997-2000. These two periods were selected to contrast deposition before and after the large decrease in SO2 emissions that occurred in 1995. Estimates of dry deposition were obtained from measurements at CASTNet sites combined with deposition velocities that were modeled using the multilayer model, a 20-layer model that simulates the various atmospheric processes that contribute to dry deposition. Estimates of wet deposition were obtained from measurements at sites operated bythe National Atmospheric Deposition Program. The estimates of dry and wet deposition were combined to calculate total deposition of atmospheric sulfur (dry SO2, dry and wet SO4(2-)) and nitrogen (dry HNO3, dry and wet NO3-, dry and wet NH4+). An analysis of the deposition estimates showed a significant decline in sulfur deposition and no change in nitrogen deposition. The highest rates of sulfur deposition were observed in the Ohio River Valley and downwind states. This region also observed the largest decline in sulfur deposition. The highest rates of nitrogen deposition were observed in the Midwest from Illinois to southern New York State. Sulfur and nitrogen deposition fluxes were significantly higher in the eastern United States as compared to the western sites. Dry deposition contributed approximately 38% of total sulfur deposition and 30% of total nitrogen deposition in the eastern

  14. Comparison of exposure estimation methods for air pollutants: ambient monitoring data and regional air quality simulation.

    PubMed

    Bravo, Mercedes A; Fuentes, Montserrat; Zhang, Yang; Burr, Michael J; Bell, Michelle L

    2012-07-01

    Air quality modeling could potentially improve exposure estimates for use in epidemiological studies. We investigated this application of air quality modeling by estimating location-specific (point) and spatially-aggregated (county level) exposure concentrations of particulate matter with an aerodynamic diameter less than or equal to 2.5 μm (PM(2.5)) and ozone (O(3)) for the eastern U.S. in 2002 using the Community Multi-scale Air Quality (CMAQ) modeling system and a traditional approach using ambient monitors. The monitoring approach produced estimates for 370 and 454 counties for PM(2.5) and O(3), respectively. Modeled estimates included 1861 counties, covering 50% more population. The population uncovered by monitors differed from those near monitors (e.g., urbanicity, race, education, age, unemployment, income, modeled pollutant levels). CMAQ overestimated O(3) (annual normalized mean bias=4.30%), while modeled PM(2.5) had an annual normalized mean bias of -2.09%, although bias varied seasonally, from 32% in November to -27% in July. Epidemiology may benefit from air quality modeling, with improved spatial and temporal resolution and the ability to study populations far from monitors that may differ from those near monitors. However, model performance varied by measure of performance, season, and location. Thus, the appropriateness of using such modeled exposures in health studies depends on the pollutant and metric of concern, acceptable level of uncertainty, population of interest, study design, and other factors.

  15. Ambient Air Pollution Exposure Estimation for the Global Burden of Disease 2013.

    PubMed

    Brauer, Michael; Freedman, Greg; Frostad, Joseph; van Donkelaar, Aaron; Martin, Randall V; Dentener, Frank; van Dingenen, Rita; Estep, Kara; Amini, Heresh; Apte, Joshua S; Balakrishnan, Kalpana; Barregard, Lars; Broday, David; Feigin, Valery; Ghosh, Santu; Hopke, Philip K; Knibbs, Luke D; Kokubo, Yoshihiro; Liu, Yang; Ma, Stefan; Morawska, Lidia; Sangrador, José Luis Texcalac; Shaddick, Gavin; Anderson, H Ross; Vos, Theo; Forouzanfar, Mohammad H; Burnett, Richard T; Cohen, Aaron

    2016-01-05

    Exposure to ambient air pollution is a major risk factor for global disease. Assessment of the impacts of air pollution on population health and evaluation of trends relative to other major risk factors requires regularly updated, accurate, spatially resolved exposure estimates. We combined satellite-based estimates, chemical transport model simulations, and ground measurements from 79 different countries to produce global estimates of annual average fine particle (PM2.5) and ozone concentrations at 0.1° × 0.1° spatial resolution for five-year intervals from 1990 to 2010 and the year 2013. These estimates were applied to assess population-weighted mean concentrations for 1990-2013 for each of 188 countries. In 2013, 87% of the world's population lived in areas exceeding the World Health Organization Air Quality Guideline of 10 μg/m(3) PM2.5 (annual average). Between 1990 and 2013, global population-weighted PM2.5 increased by 20.4% driven by trends in South Asia, Southeast Asia, and China. Decreases in population-weighted mean concentrations of PM2.5 were evident in most high income countries. Population-weighted mean concentrations of ozone increased globally by 8.9% from 1990-2013 with increases in most countries-except for modest decreases in North America, parts of Europe, and several countries in Southeast Asia.

  16. Satellite-based Estimates of Ambient Air Pollution and Global Variations in Childhood Asthma Prevalence

    NASA Technical Reports Server (NTRS)

    Anderson, H. Ross; Butland, Barbara K.; Donkelaar, Aaron Matthew Van; Brauer, Michael; Strachan, David P.; Clayton, Tadd; van Dingenen, Rita; Amann, Marcus; Brunekreef, Bert; Cohen, Aaron; Dentener, Frank; Lai, Christopher; Lamsal, Lok N.; Martin, Randall V.

    2012-01-01

    Background: The effect of ambient air pollution on global variations and trends in asthma prevalence is unclear. Objectives: Our goal was to investigate community-level associations between asthma prevalence data from the International Study of Asthma and Allergies in Childhood (ISAAC) and satellite-based estimates of particulate matter with aerodynamic diameter < 2.5 microm (PM2.5) and nitrogen dioxide (NO2), and modelled estimates of ozone. Methods: We assigned satellite-based estimates of PM2.5 and NO2 at a spatial resolution of 0.1deg × 0.1deg and modeled estimates of ozone at a resolution of 1deg × 1deg to 183 ISAAC centers. We used center-level prevalence of severe asthma as the outcome and multilevel models to adjust for gross national income (GNI) and center- and country-level sex, climate, and population density. We examined associations (adjusting for GNI) between air pollution and asthma prevalence over time in centers with data from ISAAC Phase One (mid-1900s) and Phase Three (2001-2003). Results: For the 13- to 14-year age group (128 centers in 28 countries), the estimated average within-country change in center-level asthma prevalence per 100 children per 10% increase in center-level PM2.5 and NO2 was -0.043 [95% confidence interval (CI): -0.139, 0.053] and 0.017 (95% CI: -0.030, 0.064) respectively. For ozone the estimated change in prevalence per parts per billion by volume was -0.116 (95% CI: -0.234, 0.001). Equivalent results for the 6- to 7-year age group (83 centers in 20 countries), though slightly different, were not significantly positive. For the 13- to 14-year age group, change in center-level asthma prevalence over time per 100 children per 10% increase in PM2.5 from Phase One to Phase Three was -0.139 (95% CI: -0.347, 0.068). The corresponding association with ozone (per ppbV) was -0.171 (95% CI: -0.275, -0.067). Conclusion: In contrast to reports from within-community studies of individuals exposed to traffic pollution, we did not find

  17. First Order Estimates of Energy Requirements for Pollution Control. Interagency Energy-Environment Research and Development Program Report.

    ERIC Educational Resources Information Center

    Barker, James L.; And Others

    This U.S. Environmental Protection Agency report presents estimates of the energy demand attributable to environmental control of pollution from stationary point sources. This class of pollution source includes powerplants, factories, refineries, municipal waste water treatment plants, etc., but excludes mobile sources such as trucks, and…

  18. A Comparison of Estimates of Atmospheric Effects on Signal Propagation Using ITU Models: Initial Study Results

    NASA Astrophysics Data System (ADS)

    Morabito, D. D.

    2014-11-01

    This article provides details on a comparison performed on calculated atmospheric effects on signal propagation using different methods for the Deep Space Network (DSN) and two Near Earth Network (NEN) sites commonly used in telecommunications link budgets. Atmospheric attenuation and scintillation fading are two of the many contributors that need to be taken into account in such link budgets between transmitter and receiver. Although atmospheric noise temperature increase is another contributor (at the receiver), it is well related to atmospheric attenuation through appropriate model equations. Telecommunication engineers working NEN link budgets make use of data and models obtained from the International Telecommunication Union (ITU) in order to estimate atmospheric effects. Such effects include atmospheric attenuation (gaseous, rain, and cloud), atmospheric noise temperature contribution, and scintillation. Because most NEN links usually operate at very high margins, uncertainties in the ITU models were not much of a concern in the past as they tended to be conservative, in comparison to links of the DSN that operate at low margins and thus require more accurate statistics on atmospheric effects. Such statistics for the DSN links make use of brightness temperature measurements from multiyear water vapor radiometer (WVR) data from instruments operating at the DSN sites. Atmospheric attenuation statistics derived from WVR data are well documented and are published by the DSN. Thus, the DSN sites make a good testbed in which to cross-compare atmospheric loss statistics with those derived from ITU data and models.

  19. Hierarchical set of models for estimating the effects of air pollution on vegetation

    SciTech Connect

    Kercher, J.R.; Axelrod, M.C.; Bingham, G.E.

    1981-05-26

    Three models have been developed to estimate the effects of air pollutants on vegetation at the photosynthetic process (PHOTO), plant (GROWl), and community (SILVA) levels of resolution. PHOTO simulates the enhancement of photosynthesis at low H/sub 2/S levels, depression of photosynthesis at high H/sub 2/S levels, and the threshold effects for sulfur pollutants. GROWl simulates the growth and development of a plant during a growing season. GROWl has been used to assess the effects on sugar beets of geothermal energy development in the Imperial Valley, California. SILVA is a community-level model simulating the effects of SO/sub 2/ on growth, species composition, and succession, for the mixed conifer forest types of the Sierra Nevada, California.

  20. Atmospheric organochlorine pollutants and air-sea exchange of hexachlorocyclohexane in the Bering and Chukchi Seas

    USGS Publications Warehouse

    Hinckley, D.A.; Bidleman, T.F.; Rice, C.P.

    1991-01-01

    Organochlorine pesticides have been found in Arctic fish, marine mammals, birds, and plankton for some time. The lack of local sources and remoteness of the region imply long-range transport and deposition of contaminants into the Arctic from sources to the south. While on the third Soviet-American Joint Ecological Expedition to the Bering and Chukchi Seas (August 1988), high-volume air samples were taken and analyzed for organochlorine pesticides. Hexachlorocyclohexane (HCH), hexachlorobenzene, polychlorinated camphenes, and chlordane (listed in order of abundance, highest to lowest) were quantified. The air-sea gas exchange of HCH was estimated at 18 stations during the cruise. Average alpha-HCH concentrations in concurrent atmosphere and surface water samples were 250 pg m-3 and 2.4 ng L-1, respectively, and average gamma-HCH concentrations were 68 pg m-3 in the atmosphere and 0.6 ng L-1 in surface water. Calculations based on experimentally derived Henry's law constants showed that the surface water was undersaturated with respect to the atmosphere at most stations (alpha-HCH, average 79% saturation; gamma-HCH, average 28% saturation). The flux for alpha-HCH ranged from -47 ng m-2 day-1 (sea to air) to 122 ng m-2 d-1 (air to sea) and averaged 25 ng m-2 d-1 air to sea. All fluxes of gamma-HCH were from air to sea, ranged from 17 to 54 ng m-2 d-1, and averaged 31 ng m-2 d-1.

  1. Atmospheric organochlorine pollutants and air-sea exchange of hexachlorocyclohexane in the Bering and Chukchi Seas

    SciTech Connect

    Hinckley, D.A.; Bidleman, T.F. ); Rice, C.P. )

    1991-04-15

    Organochlorine pesticides have been found in Arctic fish, marine mammals, birds, and plankton for some time. The lack of local sources and remoteness of the region imply long-range transport and deposition of contaminants into the Arctic from sources to the south. While on the third Soviet-American Joint Ecological Expedition to the Bering and Chukchi Seas (August 1988), high-volume air samples were taken and analyzed for organochlorine pesticides. Hexachlorocyclohexane (HCH), hexachlorobenzene, polychlorinated camphenes, and chlordane (listed in order of abundance, highest to lowest) were quantified. The air-sea gas exchange of HCH was estimated at 18 stations during the cruise. Average {alpha}-HCH concentrations in concurrent atmosphere and surface water samples were 250 pg/m{sup 3} and 2.4 ng/l, respectively, and average {gamma}-HCH concentrations were 68 pg/m{sup 3} in the atmosphere and 0.6 ng/l in surface water. Calculations based on experimentally derived Henry's law constants showed that the surface water was undersaturated with respect to the atmosphere at most stations ({alpha}-HCH, average 79% saturation; {gamma}-HCH, average 28% saturation). The flux for {alpha}-HCH ranged from {minus}47 ng/m{sup 2} day (sea to air) to 122 ng/m{sup 2} day (air to sea) and averaged 25 ng/m{sup 2} day air to sea. All fluxes of {gamma}-HCH were from air to sea, ranged from 17 to 54 ng/m{sup 2} day, and averaged 31 ng/m{sup 2} day.

  2. An adaptive technique for estimating the atmospheric density profile during the AE mission

    NASA Technical Reports Server (NTRS)

    Argentiero, P.

    1973-01-01

    A technique is presented for processing accelerometer data obtained during the AE missions in order to estimate the atmospheric density profile. A minimum variance, adaptive filter is utilized. The trajectory of the probe and probe parameters are in a consider mode where their estimates are unimproved but their associated uncertainties are permitted an impact on filter behavior. Simulations indicate that the technique is effective in estimating a density profile to within a few percentage points.

  3. Automatic parameter estimation for atmospheric turbulence mitigation techniques

    NASA Astrophysics Data System (ADS)

    Kozacik, Stephen; Paolini, Aaron; Kelmelis, Eric

    2015-05-01

    Several image processing techniques for turbulence mitigation have been shown to be effective under a wide range of long-range capture conditions; however, complex, dynamic scenes have often required manual interaction with the algorithm's underlying parameters to achieve optimal results. While this level of interaction is sustainable in some workflows, in-field determination of ideal processing parameters greatly diminishes usefulness for many operators. Additionally, some use cases, such as those that rely on unmanned collection, lack human-in-the-loop usage. To address this shortcoming, we have extended a well-known turbulence mitigation algorithm based on bispectral averaging with a number of techniques to greatly reduce (and often eliminate) the need for operator interaction. Automations were made in the areas of turbulence strength estimation (Fried's parameter), as well as the determination of optimal local averaging windows to balance turbulence mitigation and the preservation of dynamic scene content (non-turbulent motions). These modifications deliver a level of enhancement quality that approaches that of manual interaction, without the need for operator interaction. As a consequence, the range of operational scenarios where this technology is of benefit has been significantly expanded.

  4. 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

  5. Multi-model Estimates of Intercontinental Source-Receptor Relationships for Ozone Pollution

    SciTech Connect

    Fiore, A M; Dentener, F J; Wild, O; Cuvelier, C; Schultz, M G; Hess, P; Textor, C; Schulz, M; Doherty, R; Horowitz, L W; MacKenzie, I A; Sanderson, M G; Shindell, D T; Stevenson, D S; Szopa, S; Van Dingenen, R; Zeng, G; Atherton, C; Bergmann, D; Bey, I; Carmichael, G; Collins, W J; Duncan, B N; Faluvegi, G; Folberth, G; Gauss, M; Gong, S; Hauglustaine, D; Holloway, T; Isaksen, I A; Jacob, D J; Jonson, J E; Kaminski, J W; Keating, T J; Lupu, A; Marmer, E; Montanaro, V; Park, R; Pitari, G; Pringle, K J; Pyle, J A; Schroeder, S; Vivanco, M G; Wind, P; Wojcik, G; Wu, S; Zuber, A

    2008-10-16

    Understanding the surface O{sub 3} response over a 'receptor' region to emission changes over a foreign 'source' region is key to evaluating the potential gains from an international approach to abate ozone (O{sub 3}) pollution. We apply an ensemble of 21 global and hemispheric chemical transport models to estimate the spatial average surface O{sub 3} response over East Asia (EA), Europe (EU), North America (NA) and South Asia (SA) to 20% decreases in anthropogenic emissions of the O{sub 3} precursors, NO{sub x}, NMVOC, and CO (individually and combined), from each of these regions. We find that the ensemble mean surface O{sub 3} concentrations in the base case (year 2001) simulation matches available observations throughout the year over EU but overestimates them by >10 ppb during summer and early fall over the eastern U.S. and Japan. The sum of the O{sub 3} responses to NO{sub x}, CO, and NMVOC decreases separately is approximately equal to that from a simultaneous reduction of all precursors. We define a continental-scale 'import sensitivity' as the ratio of the O{sub 3} response to the 20% reductions in foreign versus 'domestic' (i.e., over the source region itself) emissions. For example, the combined reduction of emissions from the 3 foreign regions produces an ensemble spatial mean decrease of 0.6 ppb over EU (0.4 ppb from NA), less than the 0.8 ppb from the reduction of EU emissions, leading to an import sensitivity ratio of 0.7. The ensemble mean surface O{sub 3} response to foreign emissions is largest in spring and late fall (0.7-0.9 ppb decrease in all regions from the combined precursor reductions in the 3 foreign regions), with import sensitivities ranging from 0.5 to 1.1 (responses to domestic emission reductions are 0.8-1.6 ppb). High O{sub 3} values are much more sensitive to domestic emissions than to foreign emissions, as indicated by lower import sensitivities of 0.2 to 0.3 during July in EA, EU, and NA when O{sub 3} levels are typically highest

  6. CO2 Flux Estimation Errors Associated with Moist Atmospheric Processes

    NASA Technical Reports Server (NTRS)

    Parazoo, N. C.; Denning, A. S.; Kawa, S. R.; Pawson, S.; Lokupitiya, R.

    2012-01-01

    Vertical transport by moist sub-grid scale processes such as deep convection is a well-known source of uncertainty in CO2 source/sink inversion. However, a dynamical link between vertical transport, satellite based retrievals of column mole fractions of CO2, and source/sink inversion has not yet been established. By using the same offline transport model with meteorological fields from slightly different data assimilation systems, we examine sensitivity of frontal CO2 transport and retrieved fluxes to different parameterizations of sub-grid vertical transport. We find that frontal transport feeds off background vertical CO2 gradients, which are modulated by sub-grid vertical transport. The implication for source/sink estimation is two-fold. First, CO2 variations contained in moist poleward moving air masses are systematically different from variations in dry equatorward moving air. Moist poleward transport is hidden from orbital sensors on satellites, causing a sampling bias, which leads directly to small but systematic flux retrieval errors in northern mid-latitudes. Second, differences in the representation of moist sub-grid vertical transport in GEOS-4 and GEOS-5 meteorological fields cause differences in vertical gradients of CO2, which leads to systematic differences in moist poleward and dry equatorward CO2 transport and therefore the fraction of CO2 variations hidden in moist air from satellites. As a result, sampling biases are amplified and regional scale flux errors enhanced, most notably in Europe (0.43+/-0.35 PgC /yr). These results, cast from the perspective of moist frontal transport processes, support previous arguments that the vertical gradient of CO2 is a major source of uncertainty in source/sink inversion.

  7. CO2 flux estimation errors associated with moist atmospheric processes

    NASA Astrophysics Data System (ADS)

    Parazoo, N. C.; Denning, A. S.; Kawa, S. R.; Pawson, S.; Lokupitiya, R.

    2012-07-01

    Vertical transport by moist sub-grid scale processes such as deep convection is a well-known source of uncertainty in CO2 source/sink inversion. However, a dynamical link between vertical transport, satellite based retrievals of column mole fractions of CO2, and source/sink inversion has not yet been established. By using the same offline transport model with meteorological fields from slightly different data assimilation systems, we examine sensitivity of frontal CO2 transport and retrieved fluxes to different parameterizations of sub-grid vertical transport. We find that frontal transport feeds off background vertical CO2 gradients, which are modulated by sub-grid vertical transport. The implication for source/sink estimation is two-fold. First, CO2 variations contained in moist poleward moving air masses are systematically different from variations in dry equatorward moving air. Moist poleward transport is hidden from orbital sensors on satellites, causing a sampling bias, which leads directly to small but systematic flux retrieval errors in northern mid-latitudes. Second, differences in the representation of moist sub-grid vertical transport in GEOS-4 and GEOS-5 meteorological fields cause differences in vertical gradients of CO2, which leads to systematic differences in moist poleward and dry equatorward CO2 transport and therefore the fraction of CO2 variations hidden in moist air from satellites. As a result, sampling biases are amplified and regional scale flux errors enhanced, most notably in Europe (0.43 ± 0.35 PgC yr-1). These results, cast from the perspective of moist frontal transport processes, support previous arguments that the vertical gradient of CO2 is a major source of uncertainty in source/sink inversion.

  8. [The application of the multidimensional statistical methods in the evaluation of the influence of atmospheric pollution on the population's health].

    PubMed

    Surzhikov, V D; Surzhikov, D V

    2014-01-01

    The search and measurement of causal relationships between exposure to air pollution and health state of the population is based on the system analysis and risk assessment to improve the quality of research. With this purpose there is applied the modern statistical analysis with the use of criteria of independence, principal component analysis and discriminate function analysis. As a result of analysis out of all atmospheric pollutants there were separated four main components: for diseases of the circulatory system main principal component is implied with concentrations of suspended solids, nitrogen dioxide, carbon monoxide, hydrogen fluoride, for the respiratory diseases the main c principal component is closely associated with suspended solids, sulfur dioxide and nitrogen dioxide, charcoal black. The discriminant function was shown to be used as a measure of the level of air pollution.

  9. 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

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

    PubMed Central

    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 (13C 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 (Δ13C). 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 Δ13C 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 Δ13C during the pollution period. Using biomass increment-climate correlation analyses, we did not identify any clear pollution

  11. Estimation of Release History of Pollutant Source and Dispersion Coefficient of Aquifer Using Trained ANN Model

    NASA Astrophysics Data System (ADS)

    Srivastava, R.; Ayaz, M.; Jain, A.

    2013-12-01

    Knowledge of the release history of a groundwater pollutant source is critical in the prediction of the future trend of the pollutant movement and in choosing an effective remediation strategy. Moreover, for source sites which have undergone an ownership change, the estimated release history can be utilized for appropriate allocation of the costs of remediation among different parties who may be responsible for the contamination. Estimation of the release history with the help of concentration data is an inverse problem that becomes ill-posed because of the irreversible nature of the dispersion process. Breakthrough curves represent the temporal variation of pollutant concentration at a particular location, and contain significant information about the source and the release history. Several methodologies have been developed to solve the inverse problem of estimating the source and/or porous medium properties using the breakthrough curves as a known input. A common problem in the use of the breakthrough curves for this purpose is that, in most field situations, we have little or no information about the time of measurement of the breakthrough curve with respect to the time when the pollutant source becomes active. We develop an Artificial Neural Network (ANN) model to estimate the release history of a groundwater pollutant source through the use of breakthrough curves. It is assumed that the source location is known but the time dependent contaminant source strength is unknown. This temporal variation of the strength of the pollutant source is the output of the ANN model that is trained using the Levenberg-Marquardt algorithm utilizing synthetically generated breakthrough curves as inputs. A single hidden layer was used in the neural network and, to utilize just sufficient information and reduce the required sampling duration, only the upper half of the curve is used as the input pattern. The second objective of this work was to identify the aquifer parameters. An

  12. Effect of cadmium pollution of atmospheric origin on field-grown maize in two consecutive years with diverse weather conditions.

    PubMed

    Anda, Angéla; Illés, Bernadett; Soós, G

    2013-12-01

    The aim of the study was to analyse the effect of atmospheric cadmium (Cd) pollution of atmospheric origin in maize compared to a control without Cd pollution. The plant parameters investigated were the timing of phenological phases, leaf area index (LAI) and yield, while radiation and water regime parameters were represented by albedo (reflection grade) and evapotranspiration, respectively. In treatments with and without irrigation, Cd caused a significant reduction in LAI, accompanied by lower evapotranspiration. The mean annual albedo in the Cd-polluted treatment only rose to a moderate extent in 2011 (in 2010 there was hardly any change), but changes within the year were more pronounced in certain phases of development. Cd led to greater reflection of radiation by plants during the vegetative phase, so the radiation absorption of the canopy was reduced leading to a lower level of evapotranspiration. In the dry, hot year of 2011 maize plants in the non-irrigated treatments showed a substantial reduction in grain dry matter, but maize yield losses could be reduced by irrigation in areas exposed to Cd pollution.

  13. Evaluation of Observation-Fused Regional Air Quality Model Results for Population Air Pollution Exposure Estimation

    PubMed Central

    Chen, Gang; Li, Jingyi; Ying, Qi; Sherman, Seth; Perkins, Neil; Rajeshwari, Sundaram; Mendola, Pauline

    2014-01-01

    In this study, Community Multiscale Air Quality (CMAQ) model was applied to predict ambient gaseous and particulate concentrations during 2001 to 2010 in 15 hospital referral regions (HRRs) using a 36-km horizontal resolution domain. An inverse distance weighting based method was applied to produce exposure estimates based on observation-fused regional pollutant concentration fields using the differences between observations and predictions at grid cells where air quality monitors were located. Although the raw CMAQ model is capable of producing satisfying results for O3 and PM2.5 based on EPA guidelines, using the observation data fusing technique to correct CMAQ predictions leads to significant improvement of model performance for all gaseous and particulate pollutants. Regional average concentrations were calculated using five different methods: 1) inverse distance weighting of observation data alone, 2) raw CMAQ results, 3) observation-fused CMAQ results, 4) population-averaged raw CMAQ results and 5) population-averaged fused CMAQ results. It shows that while O3 (as well as NOx) monitoring networks in the HRR regions are dense enough to provide consistent regional average exposure estimation based on monitoring data alone, PM2.5 observation sites (as well as monitors for CO, SO2, PM10 and PM2.5 components) are usually sparse and the difference between the average concentrations estimated by the inverse distance interpolated observations, raw CMAQ and fused CMAQ results can be significantly different. Population-weighted average should be used to account spatial variation in pollutant concentration and population density. Using raw CMAQ results or observations alone might lead to significant biases in health outcome analyses. PMID:24747248

  14. Long Term Baseline Atmospheric Monitoring

    ERIC Educational Resources Information Center

    Goldman, Mark A.

    1975-01-01

    Describes a program designed to measure the normal concentrations of certain chemical and physical parameters of the atmosphere so that quantitative estimates can be made of local, regional, and global pollution. (GS)

  15. MAXINE: An improved methodology for estimating maximum individual dose from chronic atmospheric radioactive releases

    SciTech Connect

    Hamby, D.M.

    1994-02-01

    An EXCEL{reg_sign} spreadsheet has been developed that, when combined with the PC version of XOQDOQ, will generate estimates of maximum individual dose from routine atmospheric releases of radionuclides. The spreadsheet, MAXINE, utilizes a variety of atmospheric dispersion factors to calculate radiation dose as recommended by the US Nuclear Regulatory Commission in Regulatory Guide 1.109 [USNRC 1977a]. The methodology suggested herein includes use of both the MAXINE spreadsheet and the PC version of XOQDOQ.

  16. Uncertainty of air pollution cost estimates: to what extent does it matter?

    PubMed

    Rabl, Ari; Spadaro, Joseph V; van der Zwaan, Bob

    2005-01-15

    How large is the social cost penalty if one makes the wrong choice because of uncertainties in the estimates of the costs and benefits of environmental policy measures? For discrete choices there is no general rule other than the recommendation to always carefully compare costs and benefits when introducing policies for environmental protection. For continuous choices (e.g., the ceiling for the total emissions of a pollutant by an entire sector or region), it is instructive to look at the cost penalty as a function of the error in the incremental damage cost estimate. Using abatement cost curves for NOx, SO2, dioxins, and CO2, this paper evaluates the cost penalty for errors in the following: national emission ceilings for NOx and SO2 in each of 12 countries of Europe, an emission ceiling for dioxins in the UK, and limits for the emission of CO2 in Europe. The cost penalty turns out to be remarkably insensitive to errors. An error by a factor of 3 due to uncertainties in the damage estimates for NOx and SO2 increases the total social cost by at most 20% and in most cases much less. For dioxins, the total social cost is increased by at most 10%. For CO2, several different possible cost curves are examined: for some the sensitivity to uncertainties is greater than for the other pollutants, but even here the penalty is less than 30% and in most cases much less if the true damage costs are twice as high as the ones estimated. The paper also quantifies the benefit of improving the accuracy of damage cost estimates by further research.

  17. Improving Estimates of Atmosphere-Ocean Greenhouse Gas Fluxes for Earth-System Modelling

    NASA Astrophysics Data System (ADS)

    Vieira, V. M. N. C. S.; Sahlee, E.; Jurus, P.; Clementi, E.; Pettersson, H.; Mateus, M.

    2016-08-01

    Accurate estimates of atmosphere-ocean balances and fluxes of greenhouse gases and aerosols are fundamental for Earth-System models forecasting the climate change, and for Earth Observation estimates of oceanic sinks and sources coupling satellite imagery with reverse modelling. The standard formulations are 24 and 36 years old, and recent alternatives have emerged. We developed a framework congregating the geophysical processes involved, customizable with alternative formulations, and that can be used as basis for novel couplers of atmospheric and oceanographic model components. We tested it with fine resolution data from the European coastal ocean. Although the solubility formulations agreed well, their minor divergences yielded differences of many tons of greenhouse gases dissolved at the ocean surface. The transfer velocities largely mismatched their estimates, in part consequence of the standard formulation not considering factors that were proved determinant at the coastal ocean. Climate Change research requires further calibration and validation of atmosphere-ocean interactions.

  18. Estimation of the atmospheric corrosion on metal containers in industrial waste disposal.

    PubMed

    Baklouti, M; Midoux, N; Mazaudier, F; Feron, D

    2001-08-17

    Solid industrial waste are often stored in metal containers filled with concrete, and placed in well-aerated warehouses. Depending on meteorological conditions, atmospheric corrosion can induce severe material damages to the metal casing, and this damage has to be predicted to achieve safe storage. This work provides a first estimation of the corrosivity of the local atmosphere adjacent to the walls of the container through a realistic modeling of heat transfer phenomena which was developed for this purpose. Subsequent simulations of condensation/evaporation of the water vapor in the atmosphere were carried out. Atmospheric corrosion rates and material losses are easily deduced. For handling realistic data and comparison, two different meteorological contexts were chosen: (1) an oceanic and damp atmosphere and (2) a drier storage location. Some conclusions were also made for the storage configuration in order to reduce the extent of corrosion phenomena.

  19. Method for Fusing Observational Data and Chemical Transport Model Simulations To Estimate Spatiotemporally Resolved Ambient Air Pollution.

    PubMed

    Friberg, Mariel D; Zhai, Xinxin; Holmes, Heather A; Chang, Howard H; Strickland, Matthew J; Sarnat, Stefanie Ebelt; Tolbert, Paige E; Russell, Armistead G; Mulholland, James A

    2016-04-05

    Investigations of ambient air pollution health effects rely on complete and accurate spatiotemporal air pollutant estimates. Three methods are developed for fusing ambient monitor measurements and 12 km resolution chemical transport model (CMAQ) simulations to estimate daily air pollutant concentrations across Georgia. Temporal variance is determined by observations in one method, with the annual mean CMAQ field providing spatial structure. A second method involves scaling daily CMAQ simulated fields using mean observations to reduce bias. Finally, a weighted average of these results based on prediction of temporal variance provides optimized daily estimates for each 12 × 12 km grid. These methods were applied to daily metrics of 12 pollutants (CO, NO2, NOx, O3, SO2, PM10, PM2.5, and five PM2.5 components) over the state of Georgia for a seven-year period (2002-2008). Cross-validation demonstrates a wide range in optimized model performance across pollutants, with SO2 predicted most poorly due to limitations in coal combustion plume monitoring and modeling. For the other pollutants studied, 54-88% of the spatiotemporal variance (Pearson R(2) from cross-validation) was captured, with ozone and PM2.5 predicted best. The optimized fusion approach developed provides daily spatial field estimates of air pollutant concentrations and uncertainties that are consistent with observations, emissions, and meteorology.

  20. [Characteristics of mercury pollution in soil and atmosphere in Songhua River upstream Jia-pi-gou gold mining area].

    PubMed

    Zhang, Gang; Wang, Ning; Wang, Yuan; Liu, Te; Ai, Jian-Chao

    2012-09-01

    In the studied area of Jia-pi-gou at the upstream area of Songhua River, algamation process has been applied as a dominant method to extract gold for more than one hundred and eighty years, resulting in severe mercury environmental pollution. The total mercury contents in the atmosphere and soil have been determined by mercury analyzer (Zeeman RA915+) and cold atomic absorption spectrophotometry (GB/T 17136-1997), respectively. To study the pollution characteristics of mercury in the soil and atmosphere, the mercury flux at the interface between the soil and the atmosphere of 4 sampling sites Lao-jin-chang, Er-dao-gou, Er-dao-cha and community of Jia-pi-gou have been determined with the method of dynamic flux chamber. Furthermore, linear regression analyses on the total mercury contents between soil and atmosphere have been carried out and the correlation coefficient of mercury exchange flux between soil and atmosphere and meteorological factors has been studied. The results are as follows: (1) The mean value of mercury content in the atmosphere is (71.08 +/- 38.22) ng x m(-3). (2) The mean value of mercury content in the soil is (0.913 1 +/- 0.040 8) mg x kg(-1); it shows remarkably positive correlation between the mercury contents in soil and in the atmosphere. (3) The mercury exchange flux between soil and atmosphere in different locations are Lao-jin-chang [(129.13 +/- 496.07) ng (m2 x h)(-1)], Er-dao-gou [(98.64 +/- 43.96) ng x (m2 x h)(-1)], Er-dao-cha [(23.17 +/- 171.23) ng x (m2 x h)(-1)], and community of Jia-pi-gou [(7.12 +/- 46.33) ng x (m2 x h)(-1)]. (4) Solar radiation is the major influential factor in the mercury exchange flux between the soil and atmosphere in Lao-jin-chang, Er-dao-cha and community of Jia-pi-gou. Solar radiation, air temperature and soil temperature jointly influence the process of the mercury exchange flux between the soil and atmosphere in Er-dao-gou. Under the disturbance of terrain, three noticeably distinctive trend features

  1. Probabilistic safety analysis for urgent situations following the accidental release of a pollutant in the atmosphere

    NASA Astrophysics Data System (ADS)

    Armand, P.; Brocheton, F.; Poulet, D.; Vendel, F.; Dubourg, V.; Yalamas, T.

    2014-10-01

    This paper is an original contribution to uncertainty quantification in atmospheric transport & dispersion (AT&D) at the local scale (1-10 km). It is proposed to account for the imprecise knowledge of the meteorological and release conditions in the case of an accidental hazardous atmospheric emission. The aim is to produce probabilistic risk maps instead of a deterministic toxic load map in order to help the stakeholders making their decisions. Due to the urge attached to such situations, the proposed methodology is able to produce such maps in a limited amount of time. It resorts to a Lagrangian particle dispersion model (LPDM) using wind fields interpolated from a pre-established database that collects the results from a computational fluid dynamics (CFD) model. This enables a decoupling of the CFD simulations from the dispersion analysis, thus a considerable saving of computational time. In order to make the Monte-Carlo-sampling-based estimation of the probability field even faster, it is also proposed to recourse to the use of a vector Gaussian process surrogate model together with high performance computing (HPC) resources. The Gaussian process (GP) surrogate modelling technique is coupled with a probabilistic principal component analysis (PCA) for reducing the number of GP predictors to fit, store and predict. The design of experiments (DOE) from which the surrogate model is built, is run over a cluster of PCs for making the total production time as short as possible. The use of GP predictors is validated by comparing the results produced by this technique with those obtained by crude Monte Carlo sampling.

  2. Atmospheric mercury deposition and its contribution of the regional atmospheric transport to mercury pollution at a national forest nature reserve, southwest China.

    PubMed

    Ma, Ming; Wang, Dingyong; Du, Hongxia; Sun, Tao; Zhao, Zheng; Wei, Shiqing

    2015-12-01

    Atmospheric mercury deposition by wet and dry processes contributes to the transformation of mercury from atmosphere to terrestrial and aquatic systems. Factors influencing the amount of mercury deposited to subtropical forests were identified in this study. Throughfall and open field precipitation samples were collected in 2012 and 2013 using precipitation collectors from forest sites located across Mt. Jinyun in southwest China. Samples were collected approximately every 2 weeks and analyzed for total (THg) and methyl mercury (MeHg). Forest canopy was the primary factor on THg and MeHg deposition. Simultaneously, continuous measurements of atmospheric gaseous elemental mercury (GEM) were carried out from March 2012 to February 2013 at the summit of Mt. Jinyun. Atmospheric GEM concentrations averaged 3.8 ± 1.5 ng m(-3), which was elevated compared with global background values. Sources identification indicated that both regional industrial emissions and long-range transport of Hg from central, northeast, and southwest China were corresponded to the elevated GEM levels. Precipitation deposition fluxes of THg and MeHg in Mt. Jinyun were slightly higher than those reported in Europe and North America, whereas total fluxes of MeHg and THg under forest canopy on Mt. Jiuyun were 3 and 2.9 times of the fluxes of THg in wet deposition in the open. Highly elevated litterfall deposition fluxes suggest that even in remote forest areas of China, deposition of atmospheric Hg(0) via uptake by vegetation leaf may be a major pathway for the deposition of atmospheric Hg. The result illustrates that areas with greater atmospheric pollution can be expected to have greater fluxes of Hg to soils via throughfall and litterfall.

  3. Multimodel estimates of premature human mortality due to intercontinental transport of air pollution

    NASA Astrophysics Data System (ADS)

    Liang, C.; Silva, R.; West, J. J.; Sudo, K.; Lund, M. T.; Emmons, L. K.; Takemura, T.; Bian, H.

    2015-12-01

    Numerous modeling studies indicate that emissions from one continent influence air quality over others. Reducing air pollutant emissions from one continent can therefore benefit air quality and health on multiple continents. Here, we estimate the impacts of the intercontinental transport of ozone (O3) and fine particulate matter (PM2.5) on premature human mortality by using an ensemble of global chemical transport models coordinated by the Task Force on Hemispheric Transport of Air Pollution (TF HTAP). We use simulations of 20% reductions of all anthropogenic emissions from 13 regions (North America, Central America, South America, Europe, Northern Africa, Sub-Saharan Africa, Former Soviet Union, Middle East, East Asia, South Asia, South East Asia, Central Asia, and Australia) to calculate their impact on premature mortality within each region and elsewhere in the world. To better understand the impact of potential control strategies, we also analyze premature mortality for global 20% perturbations from five sectors individually: power and industry, ground transport, forest and savannah fires, residential, and others (shipping, aviation, and agriculture). Following previous studies, premature human mortality resulting from each perturbation scenario is calculated using a health impact function based on a log-linear model for O3 and an integrated exposure response model for PM2.5 to estimate relative risk. The spatial distribution of the exposed population (adults aged 25 and over) is obtained from the LandScan 2011 Global Population Dataset. Baseline mortality rates for chronic respiratory disease, ischemic heart disease, cerebrovascular disease, chronic obstructive pulmonary disease, and lung cancer are estimated from the GBD 2010 country-level mortality dataset for the exposed population. Model results are regridded from each model's original grid to a common 0.5°x0.5° grid used to estimate mortality. We perform uncertainty analysis and evaluate the sensitivity

  4. Atmospheric corrections of passive microwave data for estimating land surface temperature.

    PubMed

    Liu, Zeng-Lin; Wu, Hua; Tang, Bo-Hui; Qiu, Shi; Li, Zhao-Liang

    2013-07-01

    Quantitative analysis of the atmospheric effects on observations made by the Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) has been performed. The differences between observed brightness temperatures at the top of the atmosphere and at the bottom of the atmosphere were analyzed using a database of simulated observations, which were configured to replicate AMSR-E data. The differences between observed brightness temperatures at the top of the atmosphere and land surface-emitted brightness temperatures were also computed. Quantitative results show that the atmosphere has different effects on brightness temperatures in different AMSR-E channels. Atmospheric effects can be neglected at 6.925 and 10.65 GHz, when the standard deviation is less than 1 K. However, at other frequencies and polarizations, atmospheric effects on observations should not be neglected. An atmospheric correction algorithm was developed at 18.7 GHz vertical polarization, based on the classic split-window algorithm used in thermal remote sensing. Land surface emission can be estimated with RMSE = 0.99 K using the proposed method. Using the known land surface emissivity, Land Surface Temperature (LST) can be retrieved. The RMSE of retrieved LST is 1.17 K using the simulated data.

  5. Nutrient load estimation in nonpoint source pollution of Hong Kong region.

    PubMed

    Li, H E; Lee, J H W; Koenig, A; Jayawardena, A W

    2005-01-01

    Red tides and eutrophication have been frequently observed over the past two decades in coastal waters around Hong Kong, which are caused by many factors and one of them is the nutrient from nonpoint source pollution (NSP). This paper concentrates on the nutrients carried by river flow from watersheds. Since there are no systematical data sets of nonpoint source pollution in Hong Kong, monthly river water quality measurements, rainfall and river flow data, land uses, and other related information are used to analyze the characteristics of NSP and estimate the nutrient loads for Hong Kong region. Main achievements are as follows: firstly, besides mean concentration for single land use, the concept of integrated mean concentration for mixed land uses was proposed and applied. Secondly, mean concentrations were carried out for different land uses (agriculture, town, grassland, shrubland and woodland), each Water Control Zone, and Hong Kong region. Thirdly, the annual nutrient loads were estimated, for the first time in this paper, with various methods for the whole area of Hong Kong, and about 8000 tons of TN and 1500 tons TP are transported into coastal waters from Hong Kong's land in 1998.

  6. Bayesian kernel machine regression for estimating the health effects of multi-pollutant mixtures.

    PubMed

    Bobb, Jennifer F; Valeri, Linda; Claus Henn, Birgit; Christiani, David C; Wright, Robert O; Mazumdar, Maitreyi; Godleski, John J; Coull, Brent A

    2015-07-01

    Because humans are invariably exposed to complex chemical mixtures, estimating the health effects of multi-pollutant exposures is of critical concern in environmental epidemiology, and to regulatory agencies such as the U.S. Environmental Protection Agency. However, most health effects studies focus on single agents or consider simple two-way interaction models, in part because we lack the statistical methodology to more realistically capture the complexity of mixed exposures. We introduce Bayesian kernel machine regression (BKMR) as a new approach to study mixtures, in which the health outcome is regressed on a flexible function of the mixture (e.g. air pollution or toxic waste) components that is specified using a kernel function. In high-dimensional settings, a novel hierarchical variable selection approach is incorporated to identify important mixture components and account for the correlated structure of the mixture. Simulation studies demonstrate the success of BKMR in estimating the exposure-response function and in identifying the individual components of the mixture responsible for health effects. We demonstrate the features of the method through epidemiology and toxicology applications.

  7. Estimation of River Pollution Index in a Tidal Stream Using Kriging Analysis

    PubMed Central

    Chen, Yen-Chang; Yeh, Hui-Chung; Wei, Chiang

    2012-01-01

    Tidal streams are complex watercourses that represent a transitional zone between riverine and marine systems; they occur where fresh and marine waters converge. Because tidal circulation processes cause substantial turbulence in these highly dynamic zones, tidal streams are the most productive of water bodies. Their rich biological diversity, combined with the convenience of land and water transports, provide sites for concentrated populations that evolve into large cities. Domestic wastewater is generally discharged directly into tidal streams in Taiwan, necessitating regular evaluation of the water quality of these streams. Given the complex flow dynamics of tidal streams, only a few models can effectively evaluate and identify pollution levels. This study evaluates the river pollution index (RPI) in tidal streams by using kriging analysis. This is a geostatistical method for interpolating random spatial variation to estimate linear grid points in two or three dimensions. A kriging-based method is developed to evaluate RPI in tidal streams, which is typically considered as 1D in hydraulic engineering. The proposed method efficiently evaluates RPI in tidal streams with the minimum amount of water quality data. Data of the Tanshui River downstream reach available from an estuarine area validate the accuracy and reliability of the proposed method. Results of this study demonstrate that this simple yet reliable method can effectively estimate RPI in tidal streams. PMID:23202672

  8. Estimation of river pollution index in a tidal stream using kriging analysis.

    PubMed

    Chen, Yen-Chang; Yeh, Hui-Chung; Wei, Chiang

    2012-08-29

    Tidal streams are complex watercourses that represent a transitional zone between riverine and marine systems; they occur where fresh and marine waters converge. Because tidal circulation processes cause substantial turbulence in these highly dynamic zones, tidal streams are the most productive of water bodies. Their rich biological diversity, combined with the convenience of land and water transports, provide sites for concentrated populations that evolve into large cities. Domestic wastewater is generally discharged directly into tidal streams in Taiwan, necessitating regular evaluation of the water quality of these streams. Given the complex flow dynamics of tidal streams, only a few models can effectively evaluate and identify pollution levels. This study evaluates the river pollution index (RPI) in tidal streams by using kriging analysis. This is a geostatistical method for interpolating random spatial variation to estimate linear grid points in two or three dimensions. A kriging-based method is developed to evaluate RPI in tidal streams, which is typically considered as 1D in hydraulic engineering. The proposed method efficiently evaluates RPI in tidal streams with the minimum amount of water quality data. Data of the Tanshui River downstream reach available from an estuarine area validate the accuracy and reliability of the proposed method. Results of this study demonstrate that this simple yet reliable method can effectively estimate RPI in tidal streams.

  9. Evaluating near highway air pollutant levels and estimating emission factors: Case study of Tehran, Iran.

    PubMed

    Nayeb Yazdi, Mohammad; Delavarrafiee, Maryam; Arhami, Mohammad

    2015-12-15

    A field sampling campaign was implemented to evaluate the variation in air pollutants levels near a highway in Tehran, Iran (Hemmat highway). The field measurements were used to estimate road link-based emission factors for average vehicle fleet. These factors were compared with results of an in tunnel measurement campaign (in Resalat tunnel). Roadside and in-tunnel measurements of carbon monoxide (CO) and size-fractionated particulate matter (PM) were conducted during the field campaign. The concentration gradient diagrams showed exponential decay, which represented a substantial decay, more than 50-80%, in air pollutants level in a distance between 100 and 150meters (m) of the highway. The changes in particle size distribution by distancing from highway were also captured and evaluated. The results showed particle size distribution shifted to larger size particles by distancing from highway. The empirical emission factors were obtained by using the roadside and in tunnel measurements with a hypothetical box model, floating machine model, CALINE4, CT-EMFAC or COPERT. Average CO emission factors were estimated to be in a range of 4 to 12g/km, and those of PM10 were 0.1 to 0.2g/km, depending on traffic conditions. Variations of these emission factors under real working condition with speeds were determined.

  10. Atmospheric pollution due to mobile sources and effects on human health in Japan.

    PubMed Central

    Kagawa, J

    1994-01-01

    Following the rapid economic growth after World War II, diseases associated with environmental pollution frequently occurred due to delayed implementation of countermeasures against environmental pollution. These diseases are exemplified by Minamata disease, Itai-itai disease, chronic arsenic poisoning, and Yokkaichi asthma. After multiple episodes of these pollution-related diseases were experienced, the government and the private sector made joint efforts to reduce environmental pollution. As a result of these efforts and because of changes in the industrial structure, pollution-related diseases have declined. Instead, however, air pollution from automobile exhaust and the health effects of automobile exhaust on people living along roads with heavy traffic began to attract the public's attention after an increase in the use of automobiles. The epidemiological surveys carried out by the Environmental Agency and the Tokyo Metropolitan Government also have suggested unfavorable effects of automobile-caused air pollution on people living in large cities or along major roads. To solve this problem, it seems imperative to promote the reasonable use of automobiles and to work toward more efficient transportation of goods based on analyses of city structure, the life-styles of city dwellers, and the socioeconomic composition of cities. In addition, the discharge of pollutants from automobiles could be controlled. PMID:7529709

  11. 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...

  12. Effects of Point Source Atmospheric Pollution on Boreal Forest Vegetation of Northwestern Siberia,

    DTIC Science & Technology

    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

  13. Atmospheric pollution due to mobile sources and effects on human health in Japan.

    PubMed

    Kagawa, J

    1994-10-01

    Following the rapid economic growth after World War II, diseases associated with environmental pollution frequently occurred due to delayed implementation of countermeasures against environmental pollution. These diseases are exemplified by Minamata disease, Itai-itai disease, chronic arsenic poisoning, and Yokkaichi asthma. After multiple episodes of these pollution-related diseases were experienced, the government and the private sector made joint efforts to reduce environmental pollution. As a result of these efforts and because of changes in the industrial structure, pollution-related diseases have declined. Instead, however, air pollution from automobile exhaust and the health effects of automobile exhaust on people living along roads with heavy traffic began to attract the public's attention after an increase in the use of automobiles. The epidemiological surveys carried out by the Environmental Agency and the Tokyo Metropolitan Government also have suggested unfavorable effects of automobile-caused air pollution on people living in large cities or along major roads. To solve this problem, it seems imperative to promote the reasonable use of automobiles and to work toward more efficient transportation of goods based on analyses of city structure, the life-styles of city dwellers, and the socioeconomic composition of cities. In addition, the discharge of pollutants from automobiles could be controlled.

  14. Mixing state of particles with secondary species by single particle aerosol mass spectrometer in an atmospheric pollution event

    NASA Astrophysics Data System (ADS)

    Xu, Lingling; Chen, Jinsheng

    2016-04-01

    Single particle aerosol mass spectrometer (SPAMS) was used to characterize size distribution, chemical composition, and mixing state of particles in an atmospheric pollution event during 20 Oct. - 5 Nov., 2015 in Xiamen, Southeast China. A total of 533,012 particle mass spectra were obtained and clustered into six groups, comprising of industry metal (4.5%), dust particles (2.6%), carbonaceous species (70.7%), K-Rich particles (20.7%), seasalt (0.6%) and other particles (0.9%). Carbonaceous species were further divided into EC (70.6%), OC (28.5%), and mixed ECOC (0.9%). There were 61.7%, 58.3%, 4.0%, and 14.6% of particles internally mixed with sulfate, nitrate, ammonium and C2H3O, respectively, indicating that these particles had undergone significant aging processing. Sulfate was preferentially mixed with carbonaceous particles, while nitrate tended to mix with metal-containing and dust particles. Compared to clear days, the fractions of EC-, metal- and dust particles remarkably increased, while the fraction of OC-containing particles decreased in pollution days. The mixing state of particles, excepted for OC-containing particles with secondary species was much stronger in pollution days than that in clear days, which revealed the significant influence of secondary particles in atmospheric pollution. The different activity of OC-containing particles might be related to their much smaller aerodynamic diameter. These results could improve our understanding of aerosol characteristics and could be helpful to further investigate the atmospheric process of particles.

  15. Inverse estimation of radon flux distribution for East Asia using measured atmospheric radon concentration.

    PubMed

    Hirao, S; Hayashi, R; Moriizumi, J; Yamazawa, H; Tohjima, Y; Mukai, H

    2015-11-01

    In this study, the (222)Rn flux density distribution at surface was estimated in East Asia with the Bayesian synthesis inversion using measurement data and a long-range atmospheric (222)Rn transport model. Surface atmospheric (222)Rn concentrations measured at Hateruma Island in January 2008 were used. The estimated (222)Rn flux densities were generally higher than the prior ones. The area-weighted mean (222)Rn flux density for East Asia in January 2008 was estimated to be 44.0 mBq m(-2) s(-1). The use of the estimated (222)Rn flux density improved the discrepancy of the model-calculated concentrations with the measurements at Hateruma Island.

  16. Atmospheric transport of persistent organic pollutants - development of a 3-d dynamical transport model covering the northern hemisphere

    NASA Astrophysics Data System (ADS)

    Hansen, K. M.; Christensen, J. H.; Geels, C.; Frohn, L. M.; Brandt, J.

    2003-04-01

    The Danish Eulerian Hemispheric Model (DEHM) is a 3-D dynamical atmospheric transport model originally developed to describe the atmospheric transport of sulphur, lead, and mercury to the Arctic. The model has been validated carefully for these compounds. A new version of DEHM is currently being developed to describe the atmospheric transport of persistent organic pollutants (POPs) which are toxic, lipophilic and bio-accumulating compounds showing great persistence in the environment. The model has a horizontal resolution of 150 km x 150 km and 18 vertical layers, and it is driven by meteorological data from the numerical weather prediction model MM5V2. During environmental cycling POPs can be deposited and re-emitted several times before reaching a final destination. A description of the exchange processes between the land/ocean surfaces and the atmosphere is included in the model to account for this multi-hop transport. The present model version describes the atmospheric transport of the pesticide alpha-hexachlorocyclohexane (alpha-HCH). Other POPs may be included when proper data on emissions and physical-chemical parameters becomes available. The model-processes and the first model results are presented. The atmospheric transport of alpha-HCH for the 1990s is well described by the model.

  17. Triple Isotopic Composition of Atmospheric Carbonates: A Novel Technique to Identify Heterogeneous Chemistry on Aerosol Surfaces in Polluted Environment

    NASA Astrophysics Data System (ADS)

    Shaheen, R.; Horn, J.; Dominguez, G.; Masterson, A.; Ivanov, A. V.; Thiemens, M. H.

    2009-12-01

    In the ambient atmosphere, the physical and chemical properties of aerosol vary greatly between location and time due to various heterogeneous and photochemical reactions in the atmosphere. In polluted urban environments, the aerosol and gaseous mixtures interact to produce new compounds and particulates; consequently humans are exposed to many as yet undetected species. Studies of actual chemically-active, airborne particulates can better address the interaction of complex particulate and gaseous pollutant mixtures, however, it is notoriously difficult to measure chemical transformations of aerosols. Here we describe a new technique that can be used to understand the chemical transformation occurring on the surface of aerosols and thus to quantify the interaction of gaseous species and aerosol in the atmosphere. Fine and coarse aerosol samples were collected on filter papers in La Jolla, CA, USA for one week. The aerosol samples were digested with phosphoric acid and CO2 released was purified chromatographically and analyzed for 13 C. To obtain independent measurements of oxygen isotopes, the CO2 was fluorinated and oxygen gas obtained was analyzed using Mat253 Isotope Ratio Mass Spectrometer. The data indicated an excess 17O (0.6 to 4‰) in atmospheric carbonates. The oxygen isotope anomaly in atmospheric carbonates has been observed for the first time and it showed a highly significant correlation (r2 = 0.90) with urban index; an indirect measure of ozone chemistry. The δ13C in atmospheric carbonates was found to vary from -18 to -40‰. Controlled laboratory experiments to understand the origin and variation in the C and O isotopic composition of atmospheric carbonates were conducted using various mineral surfaces. Isotopic measurements of in-situ formed carbonated on CaOH, CaO, MgO, SiO2,Cu, CuO, Ni and Fe2O3 due to chemisorbed CO2 in the presence of thin water films were performed and we found that the δ13C in these carbonates ranged from -12 to -24

  18. Atmospheric deposition of toxic pollutants to the Great Lakes as measured by the integrated atmospheric deposition network

    SciTech Connect

    Hillery, B.R.; Simcik, M.F.; Basu, I.

    1998-08-01

    To determine atmospheric deposition of anthropogenic contaminants to the Great Lakes, the US and Canada established the Integrated Atmospheric Deposition Network (IADN), designed to collect regional data representative of the air over the lakes. In this paper, the authors present an update of atmospheric loadings to the Great Lakes for seven organochlorine pesticides, four polychlorinated biphenyl (PCB) congeners and total-PCBs, four polycyclic aromatic hydrocarbons (PAHs), and four trace metals. Calculations are based on gas, particle, and precipitation samples obtained in 1993 and 1994 at the five master IADN sampling stations. Air-water exchange is the dominant process for most organochlorines and lower molecular weight PAHs. Within the uncertainty in the data given here, current atmospheric loadings are indistinguishable from air-water equilibrium having been achieved over the lakes. In other words, the deposition of most organochlorine compounds into the Great Lakes is about balanced by the evaporation of these compounds from the lakes. Uncertainties in gas-transfer loadings are due to the inexact knowledge of physiochemical parameters, averaging of data over long time scales, and insufficient data for nonatmospheric sources.

  19. The Ability of Atmospheric Data to Reduce Disagreements in Wetland Methane Flux Estimates over North America

    NASA Astrophysics Data System (ADS)

    Miller, S. M.; Andrews, A. E.; Benmergui, J. S.; Commane, R.; Dlugokencky, E. J.; Janssens-Maenhout, G.; Melton, J. R.; Michalak, A. M.; Sweeney, C.; Worthy, D. E. J.

    2015-12-01

    Existing estimates of methane fluxes from wetlands differ in both magnitude and distribution across North America. We discuss seven different bottom-up methane estimates in the context of atmospheric methane data collected across the US and Canada. In the first component of this study, we explore whether the observation network can even detect a methane pattern from wetlands. We find that the observation network can identify a methane pattern from Canadian wetlands but not reliably from US wetlands. Over Canada, the network can even identify spatial patterns at multi-provence scales. Over the US, by contrast, anthropogenic emissions and modeling errors obscure atmospheric patterns from wetland fluxes. In the second component of the study, we then use these observations to reconcile disagreements in the magnitude, seasonal cycle, and spatial distribution of existing estimates. Most existing estimates predict fluxes that are too large with a seasonal cycle that is too narrow. A model known as LPJ-Bern has a spatial distribution most consistent with atmospheric observations. By contrast, a spatially-constant model outperforms the distribution of most existing flux estimates across Canada. The results presented here provide several pathways to reduce disagreements among existing wetland flux estimates across North America.

  20. [Pollution characteristics and health risk assessment of atmospheric VOCs in the downtown area of Guangzhou, China].

    PubMed

    Li, Lei; Li, Hong; Wang, Xue-Zhong; Zhang, Xin-Min; Wen, Chong

    2013-12-01

    The measurements of 31 kinds of VOCs in the ambient air of a site were carried out in the downtown of Guangzhou by online method from November 5, 2009 to November 9, 2009. The ambient level and composition characteristics, temporal variation characteristics, sources identification, and chemical reactivity of VOCs were studied, and the health risk of VOCs in the ambient air in the study area was assessed by using the international recognized health risk assessment method. Results showed that the mean and the range of the mass concentrations of 31 VOCs were 114.51 microg x m(-3) and 29.42-546.06 microg x m(-3), respectively. The mass concentrations of 31 VOCs, and those of alkanes, alkenes, and aromatics all showed a changing trend of higher in the morning and in the evening, and lower at noontime. Vehicular exhaust, gasoline and liquefied petroleum gas evaporates were the main sources of VOCs with the volatilization of paints and solvents being important emission sources. Toluene, trans-2-butene, m/p-xylene, i-butane, and 1,3,5-trimethylbenzene were the key reactive species among the 31 VOCs. Vehicular exhaust and gasoline evaporation were the main sources of VOCs leading to the formation of ozone. Health risk assessment showed that n-hexane, 1,3-butadiene, benzene, toluene, ethylbenzene, m/p-xylene and o-xylene had no appreciable risk of adverse non-cancer health effect on the exposed population, but 1, 3-butadiene and benzene had potential cancer risk. By comparing the corresponding data about health risk assessment of benzene compounds in some cities in China, it is concluded that benzene can impose relatively high cancer risk to the exposed populations in the ambient air of some cities in China. Therefore, strict countermeasures should be taken to further control the pollution of benzene in the ambient air of cities, and it is imperative to start the related studies and develop the atmospheric environmental health criteria and national ambient air quality

  1. A novel modelling framework to prioritize estimation of non-point source pollution parameters for quantifying pollutant origin and discharge in urban catchments.

    PubMed

    Fraga, I; Charters, F J; O'Sullivan, A D; Cochrane, T A

    2016-02-01

    Stormwater runoff in urban catchments contains heavy metals (zinc, copper, lead) and suspended solids (TSS) which can substantially degrade urban waterways. To identify these pollutant sources and quantify their loads the MEDUSA (Modelled Estimates of Discharges for Urban Stormwater Assessments) modelling framework was developed. The model quantifies pollutant build-up and wash-off from individual impervious roof, road and car park surfaces for individual rain events, incorporating differences in pollutant dynamics between surface types and rainfall characteristics. This requires delineating all impervious surfaces and their material types, the drainage network, rainfall characteristics and coefficients for the pollutant dynamics equations. An example application of the model to a small urban catchment demonstrates how the model can be used to identify the magnitude of pollutant loads, their spatial origin and the response of the catchment to changes in specific rainfall characteristics. A sensitivity analysis then identifies the key parameters influencing each pollutant load within the stormwater given the catchment characteristics, which allows development of a targeted calibration process that will enhance the certainty of the model outputs, while minimizing the data collection required for effective calibration. A detailed explanation of the modelling framework and pre-calibration sensitivity analysis is presented.

  2. A Useful Tool for Atmospheric Correction and Surface Temperature Estimation of Landsat Infrared Thermal Data

    NASA Astrophysics Data System (ADS)

    Rivalland, Vincent; Tardy, Benjamin; Huc, Mireille; Hagolle, Olivier; Marcq, Sébastien; Boulet, Gilles

    2016-04-01

    Land Surface temperature (LST) is a critical variable for studying the energy and water budgets at the Earth surface, and is a key component of many aspects of climate research and services. The Landsat program jointly carried out by NASA and USGS has been providing thermal infrared data for 40 years, but no associated LST product has been yet routinely proposed to community. To derive LST values, radiances measured at sensor-level need to be corrected for the atmospheric absorption, the atmospheric emission and the surface emissivity effect. Until now, existing LST products have been generated with multi channel methods such as the Temperature/Emissivity Separation (TES) adapted to ASTER data or the generalized split-window algorithm adapted to MODIS multispectral data. Those approaches are ill-adapted to the Landsat mono-window data specificity. The atmospheric correction methodology usually used for Landsat data requires detailed information about the state of the atmosphere. This information may be obtained from radio-sounding or model atmospheric reanalysis and is supplied to a radiative transfer model in order to estimate atmospheric parameters for a given coordinate. In this work, we present a new automatic tool dedicated to Landsat thermal data correction which improves the common atmospheric correction methodology by introducing the spatial dimension in the process. The python tool developed during this study, named LANDARTs for LANDsat Automatic Retrieval of surface Temperature, is fully automatic and provides atmospheric corrections for a whole Landsat tile. Vertical atmospheric conditions are downloaded from the ERA Interim dataset from ECMWF meteorological organization which provides them at 0.125 degrees resolution, at a global scale and with a 6-hour-time step. The atmospheric correction parameters are estimated on the atmospheric grid using the commercial software MODTRAN, then interpolated to 30m resolution. We detail the processing steps

  3. Channel estimation for OFDM system in atmospheric optical communication based on compressive sensing

    NASA Astrophysics Data System (ADS)

    Zhao, Qingsong; Hao, Shiqi; Geng, Hongjian; Sun, Han

    2015-10-01

    Orthogonal frequency division multiplexing (OFDM) technique applied to the atmospheric optical communication can improve data transmission rate, restrain pulse interference, and reduce effect of multipath caused by atmospheric scattering. Channel estimation, as one of the important modules in OFDM, has been investigated thoroughly and widely with great progress. In atmospheric optical communication system, channel estimation methods based on pilot are common approaches, such as traditional least-squares (LS) algorithm and minimum mean square error (MMSE) algorithm. However, sensitivity of the noise effects and high complexity of computation are shortcomings of LS algorithm and MMSE algorithm, respectively. Here, a new method based on compressive sensing is proposed to estimate the channel state information of atmospheric optical communication OFDM system, especially when the condition is closely associated with turbulence. Firstly, time-varying channel model is established under the condition of turbulence. Then, in consideration of multipath effect, sparse channel model is available for compressive sensing. And, the pilot signal is reconstructed with orthogonal matching tracking (OMP) algorithm, which is used for reconstruction. By contrast, the work of channel estimation is completed by LS algorithm as well. After that, simulations are conducted respectively in two different indexes -signal error rate (SER) and mean square error (MSE). Finally, result shows that compared with LS algorithm, the application of compressive sensing can improve the performance of SER and MSE. Theoretical analysis and simulation results show that the proposed method is reasonable and efficient.

  4. Comparison of Mars Atmospheric Density Estimates from Models to Measurements from Mars Global Surveyor (MGS) Data

    NASA Technical Reports Server (NTRS)

    Justh, Hilary L.; Justus, C. G.

    2009-01-01

    A recent study (Desai, 2008) has shown that the actual landing sites of Mars Pathfinder, the Mars Exploration Rovers (Spirit and Opportunity) and the Phoenix Mars Lander have been further downrange than predicted by models prior to landing Desai's reconstruction of their entries into the Martian atmosphere showed that the models consistently predicted higher densities than those found upon entry, descent and landing. Desai's results have raised a question as to whether there is a systemic problem within Mars atmospheric models. Proposal is to compare Mars atmospheric density estimates from Mars atmospheric models to measurements made by Mars Global Surveyor (MGS). Comparison study requires the completion of several tasks that would result in a greater understanding of reasons behind the discrepancy found during recent landings on Mars and possible solutions to this problem.

  5. Estimation of Atmospheric Path Delays in TerraSAR-X Data using Models vs. Measurements

    PubMed Central

    Jehle, Michael; Perler, Donat; Small, David; Schubert, Adrian; Meier, Erich

    2008-01-01

    Spaceborne synthetic aperture radar (SAR) measurements of the Earth's surface depend on electromagnetic waves that are subject to atmospheric path delays, in turn affecting geolocation accuracy The atmosphere influences radar signal propagation by modifying its velocity and direction, effects which can be modeled. We use TerraSAR-X (TSX) data to investigate improvements in the knowledge of the scene geometry. To precisely estimate atmospheric path delays, we analyse the signal return of four corner reflectors with accurately surveyed positions (based on differential GPS), placed at different altitudes yet with nearly identical slant ranges to the sensor. The comparison of multiple measurements with path delay models under these geometric conditions also makes it possible to evaluate the corrections for the atmospheric path delay made by the TerraSAR processor and to propose possible improvements. PMID:27873997

  6. Optimal Atmospheric Correction for Above-Ground Forest Biomass Estimation with the ETM+ Remote Sensor.

    PubMed

    Nguyen, Hieu Cong; Jung, Jaehoon; Lee, Jungbin; Choi, Sung-Uk; Hong, Suk-Young; Heo, Joon

    2015-07-31

    The reflectance of the Earth's surface is significantly influenced by atmospheric conditions such as water vapor content and aerosols. Particularly, the absorption and scattering effects become stronger when the target features are non-bright objects, such as in aqueous or vegetated areas. For any remote-sensing approach, atmospheric correction is thus required to minimize those effects and to convert digital number (DN) values to surface reflectance. The main aim of this study was to test the three most popular atmospheric correction models, namely (1) Dark Object Subtraction (DOS); (2) Fast Line-of-sight Atmospheric Analysis of Spectral Hypercubes (FLAASH) and (3) the Second Simulation of Satellite Signal in the Solar Spectrum (6S) and compare them with Top of Atmospheric (TOA) reflectance. By using the k-Nearest Neighbor (kNN) algorithm, a series of experiments were conducted for above-ground forest biomass (AGB) estimations of the Gongju and Sejong region of South Korea, in order to check the effectiveness of atmospheric correction methods for Landsat ETM+. Overall, in the forest biomass estimation, the 6S model showed the bestRMSE's, followed by FLAASH, DOS and TOA. In addition, a significant improvement of RMSE by 6S was found with images when the study site had higher total water vapor and temperature levels. Moreover, we also tested the sensitivity of the atmospheric correction methods to each of the Landsat ETM+ bands. The results confirmed that 6S dominates the other methods, especially in the infrared wavelengths covering the pivotal bands for forest applications. Finally, we suggest that the 6S model, integrating water vapor and aerosol optical depth derived from MODIS products, is better suited for AGB estimation based on optical remote-sensing data, especially when using satellite images acquired in the summer during full canopy development.

  7. Optimal Atmospheric Correction for Above-Ground Forest Biomass Estimation with the ETM+ Remote Sensor

    PubMed Central

    Nguyen, Hieu Cong; Jung, Jaehoon; Lee, Jungbin; Choi, Sung-Uk; Hong, Suk-Young; Heo, Joon

    2015-01-01

    The reflectance of the Earth’s surface is significantly influenced by atmospheric conditions such as water vapor content and aerosols. Particularly, the absorption and scattering effects become stronger when the target features are non-bright objects, such as in aqueous or vegetated areas. For any remote-sensing approach, atmospheric correction is thus required to minimize those effects and to convert digital number (DN) values to surface reflectance. The main aim of this study was to test the three most popular atmospheric correction models, namely (1) Dark Object Subtraction (DOS); (2) Fast Line-of-sight Atmospheric Analysis of Spectral Hypercubes (FLAASH) and (3) the Second Simulation of Satellite Signal in the Solar Spectrum (6S) and compare them with Top of Atmospheric (TOA) reflectance. By using the k-Nearest Neighbor (kNN) algorithm, a series of experiments were conducted for above-ground forest biomass (AGB) estimations of the Gongju and Sejong region of South Korea, in order to check the effectiveness of atmospheric correction methods for Landsat ETM+. Overall, in the forest biomass estimation, the 6S model showed the bestRMSE’s, followed by FLAASH, DOS and TOA. In addition, a significant improvement of RMSE by 6S was found with images when the study site had higher total water vapor and temperature levels. Moreover, we also tested the sensitivity of the atmospheric correction methods to each of the Landsat ETM+ bands. The results confirmed that 6S dominates the other methods, especially in the infrared wavelengths covering the pivotal bands for forest applications. Finally, we suggest that the 6S model, integrating water vapor and aerosol optical depth derived from MODIS products, is better suited for AGB estimation based on optical remote-sensing data, especially when using satellite images acquired in the summer during full canopy development. PMID:26263996

  8. Source apportionment of atmospheric pollutants based on the online data by using PMF and ME2 models at a megacity, China

    NASA Astrophysics Data System (ADS)

    Liu, Baoshuang; Yang, Jiamei; Yuan, Jie; Wang, Jiao; Dai, Qili; Li, Tingkun; Bi, Xiaohui; Feng, Yinchang; Xiao, Zhimei; Zhang, Yufen; Xu, Hong

    2017-03-01

    From 1st June to 31st August 2015, the online datasets (the water soluble inorganic ions (WSIIs), OC and EC in PM2.5, and SO2, NO2, NO) were measured continuously at Tianjin. Source apportionment of atmospheric pollutants was carried out by using PMF and ME2 models based on the online datasets. During summer in Tianjin, the ammonium sulfate/ammonium hydrogen sulfate might be major forms of sulfate in the atmospheric aerosol, while the ammonium nitrate might be major forms of nitrate. The poor correlation between OC and EC might be caused by the changes of emission sources and the production of secondary organic carbon (SOC). Five source-categories that contributed to atmospheric pollutants were extracted by PMF and ME2 models, respectively. The profiles calculated by PMF and ME2 models were consistent, and the source contributions estimated by the two models were also similar. The correlations (R2 = 0.84-0.94) were better on the time series of the contributed concentrations for the same source-category calculated from PMF and ME2 models. The source-categories were identified as secondary sources (the contribution of 25.4-26.1%), vehicle exhaust (23.3-25.4%), coal combustion (16.5-18.2%), crustal dust (13.2-14.0%) and biomass burning (9.1-10.2%). For the same source-category identified from PMF and ME2 models, the differences of profiles might be attributed to the differences of calculated methods from the two models and the uncertainties of the online datasets.

  9. Estimation of absolute water surface temperature based on atmospherically corrected thermal infrared multispectral scanner digital data

    NASA Technical Reports Server (NTRS)

    Anderson, James E.

    1986-01-01

    Airborne remote sensing systems, as well as those on board Earth orbiting satellites, sample electromagnetic energy in discrete wavelength regions and convert the total energy sampled into data suitable for processing by digital computers. In general, however, the total amount of energy reaching a sensor system located at some distance from the target is composed not only of target related energy, but, in addition, contains a contribution originating from the atmosphere itself. Thus, some method must be devised for removing or at least minimizing the effects of the atmosphere. The LOWTRAN-6 Program was designed to estimate atmospheric transmittance and radiance for a given atmospheric path at moderate spectral resolution over an operational wavelength region from 0.25 to 28.5 microns. In order to compute the Thermal Infrared Multispectral Scanner (TIMS) digital values which were recorded in the absence of the atmosphere, the parameters derived from LOWTRAN-6 are used in a correction equation. The TIMS data were collected at 1:00 a.m. local time on November 21, 1983, over a recirculating cooling pond for a power plant in southeastern Mississippi. The TIMS data were analyzed before and after atmospheric corrections were applied using a band ratioing model to compute the absolute surface temperature of various points on the power plant cooling pond. The summarized results clearly demonstrate the desirability of applying atmospheric corrections.

  10. Assessment of the variability of atmospheric pollution in National Parks of mainland Spain

    NASA Astrophysics Data System (ADS)

    Escudero, M.; Lozano, A.; Hierro, J.; Tapia, O.; del Valle, J.; Alastuey, A.; Moreno, T.; Anzano, J.; Querol, Xavier

    2016-05-01

    Air quality in nine National Parks in mainland Spain was assessed analysing SO2, NOx, O3, PM10 and PM2.5 data from background stations. As emissions in and around parks are limited, the levels of primary pollutants are low. Concentrations of secondary pollutants are high especially in summer due to photochemical production. The geographical variability of pollutants responds to regional emission patterns and the dominant circulation regimes in different regions resulting in west-east gradients for O3 and PM. Seasonal variability of pollutants was also interpreted in virtue of transport scenarios, changes in photochemical activity and emissions variability. NOx and SO2, maximize in winter due to higher emissions while O3 and PM do it in summer due to photochemical production, lower precipitation and, in the case of PM, the occurrence of African dust outbreaks. The diurnal evolution was interpreted in virtue of variability in emissions and changes in the Planetary Boundar Layer height.

  11. Monitoring atmospheric pollutants in the biosphere reserve Wienerwald by a combined approach of biomonitoring methods and technical measurements.

    PubMed

    Krommer, Viktoria; Zechmeister, Harald G; Roder, Ingrid; Scharf, Sigrid; Hanus-Illnar, Andrea

    2007-05-01

    In this study a combined approach of bioindication results correlated with an extensive set of data on air pollution and climate was used to assess the pollution status of the Man and Biosphere Reserve Wienerwald (Austria). Bryophytes served as impact indicators (via the Index of Atmospheric Purity-method IAP) at 30 sites as well as accumulation monitors for airborne trace elements (Al, Pb, V, S, Zn, Fe, Cu, Cr, Ni, Co, Mo, Cd, As, Sb and 16 EPA-PAHs) at 10 sites within the reserve. The results of these bioindication methods were subsequently correlated with further pollution (NO(2), SO(2) and dust) and climate data (precipitation, temperature and humidity). The findings obtained clearly indicate the following: Bryophyte distribution is solely influenced by the status of air quality, without interference by climatic or site-related factors, which is in contrast to several previous investigations. IAP-values correlated significantly with NO(2) (0.553; P=0.004), SO(2) winter values (0.511; P=0.013) and PM10 (dust) (0.561; P=0.013). The results obtained via chemical analyses revealed a strong correlation with data derived from the IAP methodology. In terms of the overall air quality within the biosphere reserve Wienerwald, the north-eastern part appears to be the most affected one with a most likely pollution contribution emitted by the capital city Vienna, agriculture and neighbouring countries.

  12. The atmospheric CH4 increase since the Last Glacial Maximum. I - Source estimates

    NASA Technical Reports Server (NTRS)

    Chappellaz, Jerome A.; Fung, Inez Y.; Thompson, Anne M.

    1993-01-01

    An estimate of the distribution of wetland area and associated CH4 emission is presented for the Last Glacial Maximum (LGM, 18 kyr BP, kiloyear Before Present) and the Pre-Industrial Holocene (PIH, 9000-200 years BP). The wetland source, combined with estimates of the other biogenic sources and sink, yields total source strengths of 120 and 180 Tg CH4/yr for LGM and PIH respectively. These source strengths are shown to be consistent with source estimates inferred from a photochemical model, and point to changes in wetland CH4 source as a major factor driving the atmospheric CH4 increase from LGM to PIH.

  13. GPS-based Microenvironment Tracker (MicroTrac) Model to Estimate Time-Location of Individuals for Air Pollution Exposure Assessments: Model Evaluation in Central North Carolina

    EPA Science Inventory

    A critical aspect of air pollution exposure assessment is the estimation of the time spent by individuals in various microenvironments (ME). Accounting for the time spent in different ME with different pollutant concentrations can reduce exposure misclassifications, while failure...

  14. Estimating annual precipitation for the Colorado River Basin using oceanic-atmospheric oscillations

    NASA Astrophysics Data System (ADS)

    Kalra, Ajay; Ahmad, Sajjad

    2012-06-01

    Estimating long-lead time precipitation under the stress of increased climatic variability is a challenging task in the field of hydrology. A modified Support Vector Machine (SVM) based framework is proposed to estimate annual precipitation using oceanic-atmospheric oscillations. Oceanic-atmospheric oscillations, consisting of Pacific Decadal Oscillation (PDO), North Atlantic Oscillation (NAO), Atlantic Multidecadal Oscillation (AMO), and El Niño-Southern Oscillation (ENSO) for a period of 1900-2008, are used to generate annual precipitation estimates with a 1 year lead time. The SVM model is applied to 17 climate divisions encompassing the Colorado River Basin in the western United States. The overall results revealed that the annual precipitation in the Colorado River Basin is significantly influenced by oceanic-atmospheric oscillations. The long-term precipitation predictions for the Upper Colorado River Basin can be successfully obtained using a combination of PDO, NAO, and AMO indices, whereas coupling AMO and ENSO results in improved precipitation predictions for the Lower Colorado River Basin. The results also show that the SVM model provides better precipitation estimates compared to the Artificial Neural Network and Multivariate Linear Regression models. The annual precipitation estimates obtained using the modified SVM modeling framework may assist water managers in statistically understanding the hydrologic response in relation to large scale climate patterns within the Colorado River Basin.

  15. Atmospheric channel transfer function estimation from experimental free-space optical communications data

    NASA Astrophysics Data System (ADS)

    Reinhardt, Colin N.; Tsintikidis, Dimitris; Hammel, Stephen; Kuga, Yasuo; Ritcey, James A.; Ishimaru, Akira

    2012-03-01

    Using an 850-nanometer-wavelength free-space optical (FSO)communications system of our own design, we acquired field data for the transmitted and received signals in fog at Point Loma, CA for a range of optical depths within the multiple-scattering regime. Statistical estimators for the atmospheric channel transfer function and the related coherency function were computed directly from the experimental data. We interpret the resulting channel transfer function estimates in terms of the physics of the atmospheric propagation channel and fog aerosol particle distributions. We investigate the behavior of the estimators using both real field-test data and simulated propagation data. We compare the field-data channel transfer function estimates against the outputs from a computationally-intensive radiative-transfer theory model-based approach, which we also developed previously for the FSO multiple-scattering atmospheric channel. Our results show that the data-driven channel transfer function estimates are in close agreement with the radiative transfer modeling, and provide comparable receiver signal detection performance improvements while being significantly less time and computationally-intensive.

  16. Impacts of Mercury Pollution Controls on Atmospheric Mercury Concentration and Occupational Mercury Exposure in a Hospital.

    PubMed

    Li, Ping; Yang, Yan; Xiong, Wuyan

    2015-12-01

    Mercury (Hg) and Hg-containing products are used in a wide range of settings in hospitals. Hg pollution control measures were carried out in the pediatric ward of a hospital to decrease the possibility of Hg pollution occurring and to decrease occupational Hg exposure. Total gaseous Hg (TGM) concentrations in the pediatric ward and hair and urine Hg concentrations for the pediatric staff were determined before and after the Hg pollution control measures had been implemented. A questionnaire survey performed indicated that the pediatric staff had little understanding of Hg pollution and that appropriate disposal techniques were not always used after Hg leakage. TGM concentrations in the pediatric ward and urine Hg (UHg) concentrations for the pediatric staff were 25.7 and 22.2% lower, respectively, after the Hg pollution control measures had been implemented than before, which indicated that the control measures were effective. However, TGM concentrations in the pediatric ward remained significantly higher than background concentrations and UHg concentrations for the pediatric staff were remained significantly higher than the concentrations in control group, indicating continued existence of certain Hg pollution.

  17. The estimation of the pollutant emissions on-board vessels by means of numerical methods

    NASA Astrophysics Data System (ADS)

    Jenaru, A.; Arsenie, P.; Hanzu-Pazara, R.

    2016-08-01

    Protection of the environment, especially within the most recent years, has become a constant problem considered by the states and the governments of the world, which are more and more concerned about the serious problems caused by the continuous deterioration of the environment. The long term effects of pollution on the environment generated by the lack of penalty regulations, have directed the attention of statesmen upon the necessity of the elaboration of normative acts meant to be effective in the continuous fight with it. Maritime transportation generates approximately 4% of the total of the CO2 emissions produced by human activities. This paper is intended to present two methods of estimation of the gases emissions on-board a vessel, methods that are very useful for the crews which are exploiting them. For the determination and the validation of these methods we are going to use the determinations from the tank ship. This ship has as a main propulsion engine Wärtsilä DU Sulzer RT Flex 50 - 6 cylinders that develops a maximal power of 9720 kW and has a permanent monitoring system of the pollutant emissions. The methods we develop here are using the values of the polluting elements from the exhaust gases that are determined at the exit of the vessel from the ship yard, in the framework of the acceptance tests. These values have been introduced within the framework of a matrix in the MATHCAD program. This matrix represents the starting point of the two mentioned methods: the analytical method and the graphical method. During the study we are going to evaluate the development and validation of an analytical tool to be used to determine the standard of emissions aimed at thermal machines on ships. One of the main objectives of this article represents an objective assessment of the expediency of using non-fuels for internal combustion engines in vessels.

  18. [Establishment and application of the estimation model for agricultural non-point source pollution in the field].

    PubMed

    Li, Qiang-kun; Li, Huai-en; Hu, Ya-wei; Chen, Wei-wei; Sun, Juan

    2009-12-01

    The quantitative research on pollution loads is the basis of control, evaluation and management of non-point source pollution. The estimation of agricultural non-point source pollution loads includes two steps: evaluation of water discharge and prediction of pollutant concentration in agricultural drain. Water discharge was calculated by DRAINMOD model based on the principle of water balance on farmland. Meanwhile, the synthesis of fertilization and irrigation is used as an impulse input to the farmland, the pollutant concentration changes in agricultural drain is looked as the response process corresponding to the impulse input, the complex migratory and transforming process of pollutant in soil are expressed implied by Inverse Gaussian Probability Density Function. Based on the above, the estimation model of agricultural non-point source pollution loads at field scale was constructed. Taking the typical experimentation area of Qingtongxia Irrigation District in Ningxia as an example, the loads of nitrate nitrogen and total phosphorus in paddy-field drain was simulated by this model. The results show that the simulated accorded with measured data approximately and Nash-Suttcliffe coefficient is 0.963 and 0.945 respectively.

  19. A sparse reconstruction method for the estimation of multi-resolution emission fields via atmospheric inversion

    DOE PAGES

    Ray, J.; Lee, J.; Yadav, V.; ...

    2015-04-29

    Atmospheric inversions are frequently used to estimate fluxes of atmospheric greenhouse gases (e.g., biospheric CO2 flux fields) at Earth's surface. These inversions typically assume that flux departures from a prior model are spatially smoothly varying, which are then modeled using a multi-variate Gaussian. When the field being estimated is spatially rough, multi-variate Gaussian models are difficult to construct and a wavelet-based field model may be more suitable. Unfortunately, such models are very high dimensional and are most conveniently used when the estimation method can simultaneously perform data-driven model simplification (removal of model parameters that cannot be reliably estimated) and fitting.more » Such sparse reconstruction methods are typically not used in atmospheric inversions. In this work, we devise a sparse reconstruction method, and illustrate it in an idealized atmospheric inversion problem for the estimation of fossil fuel CO2 (ffCO2) emissions in the lower 48 states of the USA. Our new method is based on stagewise orthogonal matching pursuit (StOMP), a method used to reconstruct compressively sensed images. Our adaptations bestow three properties to the sparse reconstruction procedure which are useful in atmospheric inversions. We have modified StOMP to incorporate prior information on the emission field being estimated and to enforce non-negativity on the estimated field. Finally, though based on wavelets, our method allows for the estimation of fields in non-rectangular geometries, e.g., emission fields inside geographical and political boundaries. Our idealized inversions use a recently developed multi-resolution (i.e., wavelet-based) random field model developed for ffCO2 emissions and synthetic observations of ffCO2 concentrations from a limited set of measurement sites. We find that our method for limiting the estimated field within an irregularly shaped region is about a factor of 10 faster than conventional approaches. It also

  20. Linearly Supporting Feature Extraction for Automated Estimation of Stellar Atmospheric Parameters

    NASA Astrophysics Data System (ADS)

    Li, Xiangru; Lu, Yu; Comte, Georges; Luo, Ali; Zhao, Yongheng; Wang, Yongjun

    2015-05-01

    We describe a scheme to extract linearly supporting (LSU) features from stellar spectra to automatically estimate the atmospheric parameters {{T}{\\tt{eff} }}, log g, and [Fe/H]. “Linearly supporting” means that the atmospheric parameters can be accurately estimated from the extracted features through a linear model. The successive steps of the process are as follow: first, decompose the spectrum using a wavelet packet (WP) and represent it by the derived decomposition coefficients; second, detect representative spectral features from the decomposition coefficients using the proposed method Least Absolute Shrinkage and Selection Operator (LARS)bs; third, estimate the atmospheric parameters {{T}{\\tt{eff} }}, log g, and [Fe/H] from the detected features using a linear regression method. One prominent characteristic of this scheme is its ability to evaluate quantitatively the contribution of each detected feature to the atmospheric parameter estimate and also to trace back the physical significance of that feature. This work also shows that the usefulness of a component depends on both the wavelength and frequency. The proposed scheme has been evaluated on both real spectra from the Sloan Digital Sky Survey (SDSS)/SEGUE and synthetic spectra calculated from Kurucz's NEWODF models. On real spectra, we extracted 23 features to estimate {{T}{\\tt{eff} }}, 62 features for log g, and 68 features for [Fe/H]. Test consistencies between our estimates and those provided by the Spectroscopic Parameter Pipeline of SDSS show that the mean absolute errors (MAEs) are 0.0062 dex for log {{T}{\\tt{eff} }} (83 K for {{T}{\\tt{eff} }}), 0.2345 dex for log g, and 0.1564 dex for [Fe/H]. For the synthetic spectra, the MAE test accuracies are 0.0022 dex for log {{T}{\\tt{eff} }} (32 K for {{T}{\\tt{eff} }}), 0.0337 dex for log g, and 0.0268 dex for [Fe/H].

  1. Using native epiphytic ferns to estimate the atmospheric mercury levels in a small-scale gold mining area of West Java, Indonesia.

    PubMed

    Kono, Yuriko; Rahajoe, Joeni S; Hidayati, Nuril; Kodamatani, Hitoshi; Tomiyasu, Takashi

    2012-09-01

    Mercury pollution is caused by artisanal and small-scale gold mining (ASGM) operations along the Cikaniki River (West Java, Indonesia). The atmosphere is one of the primary media through which mercury can disperse. In this study, atmospheric mercury levels are estimated using the native epiphytic fern Asplenium nidus complex (A. nidus) as a biomonitor; these estimates shed light on the atmospheric dispersion of mercury released during mining. Samples were collected from 8 sites along the Cikaniki Basin during September-November, 2008 and September-November, 2009. The A. nidus fronds that were attached to tree trunks 1-3m above the ground were collected and measured for total mercury concentration using cold vapor atomic absorption spectrometry (CVAAS) after acid-digestion. The atmospheric mercury was collected using porous gold collectors, and the concentrations were determined using double-amalgam CVAAS. The highest atmospheric mercury concentration, 1.8 × 10(3) ± 1.6 × 10(3) ngm(-3), was observed at the mining hot spot, and the lowest concentration of mercury, 5.6 ± 2.0 ngm(-3), was observed at the remote site from the Cikaniki River in 2009. The mercury concentrations in A. nidus were higher at the mining village (5.4 × 10(3) ± 1.6 × 10(3) ngg(-1)) than at the remote site (70 ± 30 ngg(-1)). The distribution of mercury in A. nidus was similar to that in the atmosphere; a significant correlation was observed between the mercury concentrations in the air and in A. nidus (r=0.895, P<0.001, n=14). The mercury levels in the atmosphere can be estimated from the mercury concentration in A. nidus using a regression equation: log (Hg(A.nidu)/ngg(-1))=0.740 log (Hg(Air)/ngm (-3)) - 1.324.

  2. Predictive estimation of upward pollutant migration during shale gas production using satellite image processing

    NASA Astrophysics Data System (ADS)

    Lyalko, Vadim; Azimov, Oleksandr; Yakovlev, Yevgen

    2016-07-01

    The report considers the relevance of the application of modern remote aerospace and hydrogeological methods in the problems of the ecological safety for the hydrosphere during shale gas production in Ukraine. Case studies of pilot implementation of these methods are present for the Bilyaivska area adjacent to the Yuzivka licensed site within the Dnieper-Donets Depression. A number of the hydrogeological filtration parameters and the thematic processing for remote sensing data of the Earth enable to obtain the rough estimate of the temporal indices for the upward pollutant migration from the fracturing zone to the groundwater aquifers in the potential process of shale gas production (as an example the 400-Bilyaivska well). It is found that the possible variety of the active permeability in tectonic zone, which may be predicted by using remote sensing of the Earth image interpretation in vicinity of the well, is responsible for the passage time of pollution from the fracturing zone level to the groundwater aquifers one and this time interval spans 50˜5 years.

  3. A methodology for modeling photocatalytic reactors for indoor pollution control using previously estimated kinetic parameters.

    PubMed

    Passalía, Claudio; Alfano, Orlando M; Brandi, Rodolfo J

    2012-04-15

    A methodology for modeling photocatalytic reactors for their application in indoor air pollution control is carried out. The methodology implies, firstly, the determination of intrinsic reaction kinetics for the removal of formaldehyde. This is achieved by means of a simple geometry, continuous reactor operating under kinetic control regime and steady state. The kinetic parameters were estimated from experimental data by means of a nonlinear optimization algorithm. The second step was the application of the obtained kinetic parameters to a very different photoreactor configuration. In this case, the reactor is a corrugated wall type using nanosize TiO(2) as catalyst irradiated by UV lamps that provided a spatially uniform radiation field. The radiative transfer within the reactor was modeled through a superficial emission model for the lamps, the ray tracing method and the computation of view factors. The velocity and concentration fields were evaluated by means of a commercial CFD tool (Fluent 12) where the radiation model was introduced externally. The results of the model were compared experimentally in a corrugated wall, bench scale reactor constructed in the laboratory. The overall pollutant conversion showed good agreement between model predictions and experiments, with a root mean square error less than 4%.

  4. How robust are the estimated effects of air pollution on health? Accounting for model uncertainty using Bayesian model averaging.

    PubMed

    Pannullo, Francesca; Lee, Duncan; Waclawski, Eugene; Leyland, Alastair H

    2016-08-01

    The long-term impact of air pollution on human health can be estimated from small-area ecological studies in which the health outcome is regressed against air pollution concentrations and other covariates, such as socio-economic deprivation. Socio-economic deprivation is multi-factorial and difficult to measure, and includes aspects of income, education, and housing as well as others. However, these variables are potentially highly correlated, meaning one can either create an overall deprivation index, or use the individual characteristics, which can result in a variety of pollution-health effects. Other aspects of model choice may affect the pollution-health estimate, such as the estimation of pollution, and spatial autocorrelation model. Therefore, we propose a Bayesian model averaging approach to combine the results from multiple statistical models to produce a more robust representation of the overall pollution-health effect. We investigate the relationship between nitrogen dioxide concentrations and cardio-respiratory mortality in West Central Scotland between 2006 and 2012.

  5. Biases in atmospheric CO2 estimates from correlated meteorology modeling errors

    NASA Astrophysics Data System (ADS)

    Miller, S. M.; Hayek, M. N.; Andrews, A. E.; Fung, I.; Liu, J.

    2015-03-01

    Estimates of CO2 fluxes that are based on atmospheric measurements rely upon a meteorology model to simulate atmospheric transport. These models provide a quantitative link between the surface fluxes and CO2 measurements taken downwind. Errors in the meteorology can therefore cause errors in the estimated CO2 fluxes. Meteorology errors that correlate or covary across time and/or space are particularly worrisome; they can cause biases in modeled atmospheric CO2 that are easily confused with the CO2 signal from surface fluxes, and they are difficult to characterize. In this paper, we leverage an ensemble of global meteorology model outputs combined with a data assimilation system to estimate these biases in modeled atmospheric CO2. In one case study, we estimate the magnitude of month-long CO2 biases relative to CO2 boundary layer enhancements and quantify how that answer changes if we either include or remove error correlations or covariances. In a second case study, we investigate which meteorological conditions are associated with these CO2 biases. In the first case study, we estimate uncertainties of 0.5-7 ppm in monthly-averaged CO2 concentrations, depending upon location (95% confidence interval). These uncertainties correspond to 13-150% of the mean afternoon CO2 boundary layer enhancement at individual observation sites. When we remove error covariances, however, this range drops to 2-22%. Top-down studies that ignore these covariances could therefore underestimate the uncertainties and/or propagate transport errors into the flux estimate. In the second case study, we find that these month-long errors in atmospheric transport are anti-correlated with temperature and planetary boundary layer (PBL) height over terrestrial regions. In marine environments, by contrast, these errors are more strongly associated with weak zonal winds. Many errors, however, are not correlated with a single meteorological parameter, suggesting that a single meteorological proxy is

  6. Persistent Organic Pollutants (POPs) in the atmosphere of three Chilean cities using passive air samplers.

    PubMed

    Pozo, Karla; Oyola, Germán; Estellano, Victor H; Harner, Tom; Rudolph, Anny; Prybilova, Petra; Kukucka, Petr; Audi, Ondrej; Klánová, Jana; Metzdorff, America; Focardi, Silvano

    2017-05-15

    In this study passive air samplers containing polyurethane foam (PUF) disks were deployed in three cities across Chile; Santiago (STG) (n=5, sampling sites), Concepciόn (CON) (n=6) and Temuco (TEM) (n=6) from 2008 to 2009. Polychlorinated biphenyls (PCBs) (7 indicator congeners), chlorinated pesticides hexachlorocyclohexanes (HCHs), dichlorodiphenyl trichloroethanes (DDTs) and flame retardants such as polybrominated diphenyl ethers (PBDEs) were determined by gas chromatography coupled mass spectrometry (GC/MS). A sampling rate (R) typical of urban sites (4m(3)/day) was used to estimate the atmospheric concentrations of individual compounds. PCB concentrations in the air (pg/m(3)) ranged from ~1-10 (TEM), ~1-40 (STG) and 4-30 (CON). Higher molecular weight PCBs (PCB-153, -180) were detected at industrial sites (in Concepción). The HCHs showed a prevalence of γ-HCH across all sites, indicative of inputs from the use of lindane but a limited use of technical HCHs in Chile. DDTs were detected with a prevalence of p,p'-DDE accounting for ~50% of the total DDTs. PBDE concentrations in air (pg/m(3)) ranged from 1 to 55 (STG), 0.5 to 20 (CON) and from 0.4 to 10 (TEM), and were generally similar to those reported for many other urban areas globally. The pattern of PBDEs was different among the three cities; however, PBDE-209 was dominant at most of the sites. These results represent one of the few assessments of air concentrations of POPs across different urban areas within the same country. These data will support Chilean commitments as a signatory to the Stockholm Convention on POPs and for reporting as a member country of the Group of Latin America and Caribbean Countries (GRULAC) region.

  7. The study of atmospheric CO pollution over the center of Moscow in autumn period

    SciTech Connect

    Fokeeva, E.V.; Pekour, M.S.

    1996-12-31

    The results of CO near-ground concentration measurements are presented which were taken by virtue of electrochemical method at the center of Moscow during one autumn month in 1993. Simultaneous measurements were performed of the total column content of CO over Moscow making use of sun radiation absorption detection in the infrared (in the wavelength range of 4.6 mcm). To determine an urban increment of CO content over regional background the data of analogous measurements were used which were collected in the rural suburb 45 km west from Moscow center One-hour averaged near-ground CO concentration were in the limits 0.4 to 5.8 mg/m{sup 3}, and an average total column CO content vary from 0.09 to 0.167 atm*cm. The measurements were accompanied by acoustic sounding of the atmosphere boundary layer with the use of three component Doppler SODAR. The peculiarities of average and concrete diurnal variation of near-ground CO concentrations can well be interpreted by virtue of SODAR data indicating the type of stratification, the mixing height and the wind velocity during a whole day. Comparison and analysis are performed of the average diurnal variations of near-ground CO concentration in autumn and summer periods in account to the occurrence frequency of surface inversion within selected periods. Almost complete coincidence has been found of the shape of CO concentration diurnal variations with those of NO and soot. An estimate of specific CO source power in the city is performed in account to the data on the mixing height and wind velocity mean within a layer of 250 m.

  8. Atmospheric concentrations of persistent organic pollutants over the Pacific Ocean near southern Taiwan and the northern Philippines.

    PubMed

    Chao, How-Ran; Lin, Ding-Yan; Chen, Kuang-Yu; Gou, Yan-Yu; Chiou, Tsyr-Huei; Lee, Wen-Jhy; Chen, Shui-Jen; Wang, Lin-Chi

    2014-09-01

    This study investigates the atmospheric occurrence of persistent organic pollutants (POPs) over the Pacific Ocean near southern Taiwan and the northern Philippines. We determined sixty-six compounds, including polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (DLPCBs), polybrominated diphenyl ethers (PBDEs), as well as polychlorinated diphenyl ethers (PCDEs), polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), and polybrominated biphenyls (PBBs), in air samples simultaneously collected from the offshore oceanic atmosphere (n=6) and over a rural area (n=2). We calculated the atmospheric World Health Organization 2005 toxic equivalency levels (WHO2005-TEQ), for the total dioxin-like POPs, including PCDD/Fs, DLPCBs, and PBDD/Fs, being 0.00612 pg WHO2005-TEQ/m(3) and 0.0138 pg WHO2005-TEQ/m(3) over the ocean and land, respectively. We found unexpected lower averaged atmospheric PBDE concentrations in the rural area (15.9 pg/m(3)) than over the ocean (31.1 pg/m(3)) due to higher levels of the BDE209 congener, although the difference was not statistically significant. We have compared and reported our field results with previously published datasets over the global oceans, which suggest PCBs and PBDEs are the dominant chemical contaminants in the global oceanic atmosphere among these halogenated POPs (e.g. PCBs and Σdi-hepta PBDEs could be found in the range of 0.09-48.7 and 8.07-94.0 pg/m(3), respectively, including our dataset). However, there are still very few investigations on the global atmospheric levels of PBDD/Fs, PCDEs and PBBs and our data sums to these earlier studies. Finally, we point out that the halogenated POPs originated from Taiwan or the continental East Asia which could easily reach remote ocean sites via atmospheric transport.

  9. Estimation of melting points of large set of persistent organic pollutants utilizing QSPR approach.

    PubMed

    Watkins, Marquita; Sizochenko, Natalia; Rasulev, Bakhtiyor; Leszczynski, Jerzy

    2016-03-01

    The presence of polyhalogenated persistent organic pollutants (POPs), such as Cl/Br-substituted benzenes, biphenyls, diphenyl ethers, and naphthalenes has been identified in all environmental compartments. The exposure to these compounds can pose potential risk not only for ecological systems, but also for human health. Therefore, efficient tools for comprehensive environmental risk assessment for POPs are required. Among the factors vital for environmental transport and fate processes is melting point of a compound. In this study, we estimated the melting points of a large group (1419 compounds) of chloro- and bromo- derivatives of dibenzo-p-dioxins, dibenzofurans, biphenyls, naphthalenes, diphenylethers, and benzenes by utilizing quantitative structure-property relationship (QSPR) techniques. The compounds were classified by applying structure-based clustering methods followed by GA-PLS modeling. In addition, random forest method has been applied to develop more general models. Factors responsible for melting point behavior and predictive ability of each method were discussed.

  10. Using blood samples to estimate persistent organic pollutants and metals in green sea turtles (Chelonia mydas).

    PubMed

    van de Merwe, Jason P; Hodge, Mary; Olszowy, Henry A; Whittier, Joan M; Lee, Shing Y

    2010-04-01

    Persistent organic pollutants (POPs) and heavy metals have been reported in a number of green turtle (Chelonia mydas) populations worldwide. However, due to ethical considerations, these studies have generally been on tissues from deceased and stranded animals. The purpose of this study was to investigate the use of blood samples to estimate the tissue contamination of live C. mydas populations. This study analysed 125 POP compounds and eight heavy metals in the blood, liver, kidney and muscle of 16 C. mydas from the Sea World Sea Turtle Rehabilitation Program, Gold Coast, Australia. Strong correlations were observed between blood and tissue concentrations for a number of POPs and metals. Furthermore, these correlations were observed over large ranges of turtle size, sex and condition. These results indicate that blood samples are a reliable non-lethal method for predicting chemical contamination in C. mydas.

  11. "Chlorine explosion" from sea-salt aerosols in a polluted atmosphere

    NASA Astrophysics Data System (ADS)

    Buxmann, Joelle; Bleicher, Sergej; Zetzsch, Cornelius; Platt, Ulrich

    2013-04-01

    Bromine and chlorine 'explosions' (BE and CE) refer to autocatalytic, heterogeneous releases of reactive halogen species (RHS). ClO and BrO play a key role as RHS, as they influence the tropospheric oxidation capacity through destruction of ozone and fast reactions with nitrogen oxides. Besides OH radicals, Cl atoms react at a fast rate with the greenhouse gas methane, but the global effect is not clear yet. From smog-chamber experiments under tropospheric light conditions, ClO, OClO (from CE) and BrO (from BE) released from artificial sea salt aerosols were detected using a White system in combination with Differential Optical Absorption Spectroscopy (DOAS). Up to 17 ppb of ClO, 6 ppb of OClO and 1.6 ppb of BrO were observed under the influence of high NO2 and O3 concentrations. The RHS activation is triggered by NO2 reactions starting during the dark period. Formation of ClNO2 and ClONO2 and acidification of the aerosol by HNO3 or HONO play key roles. The lifetime of Cl2 of 645 s against photolysis in our smog chamber was estimated to be longer than the uptake onto the aerosol surface with a lifetime of 83s. The fact that Cl2 photolysis is slower compared to uptake, indicates that Cl2 might not be sufficient as a precursor for the observed ClO and OClO mixing rations during the chamber experiments at high NOx. Furthermore, OClO ( 40ppt/s) is formed at a faster rate than ClO ( 15ppt/s) in our experiments. A simple model, including the known gas phase reactions of halogen oxides, O3 and NOx, predicts the maximum ClO concentration to occur before the maximum OClO concentration. The measurement indicates the opposite. This suggests heterogeneous OClO formation. The lifetime of OClO against photolysis is only 20s in our chamber. But an actual heterogeneous release mechanism to form OClO has not been confirmed yet. Nevertheless, these results suggest that OClO is important for the heterogeneous release process. While BE has been demonstrated to occur in nature, the

  12. Atmospheric deposition of heavy metals in Wuxi, China: estimation based on native moss analysis.

    PubMed

    Yan, Yun; Zhang, Qiang; Wang, G Geoff; Fang, Yan-Ming

    2016-06-01

    We studied atmospheric deposition of heavy metals in Wuxi, China, using moss (Haplocladium microphyllum and H. angustifolium) as a biomonitoring agent. Moss samples were collected from 49 sites determined by a systematic sampling method. The top layer of soil on each site was also sampled. No significant correlation (P < 0.05) was observed between the moss and soil concentrations for any of the six heavy metal elements (Cd, Cr, Cu, Ni, Pb, and Zn), indicating that the soil substrate had little effect on the heavy metal concentrations in the moss materials. The metal enrichment capacity of the moss material, characterized by the concentration ratio between the moss and soil samples for each heavy metal, was topped by Cd and then followed by Zn, Pb, Cu, Cr, and Ni, respectively. Significant (P < 0.05) correlations were found among the six elements in mosses, suggesting potential anthropogenic inputs of these heavy metal pollutants. Based on concentrations of the heavy metals in mosses and the calculated contamination factors, we evaluated the contamination level of each heavy metal on the 49 sampling sites. Spatial distribution maps of heavy metal deposition for each element were interpolated using ArcGIS 9.0. A total pollution coefficient was calculated for each sampling site to identify the seriously polluted areas in the region.

  13. Biomonitoring of atmospheric pollution: a novel approach for the evaluation of natural and anthropogenic contribution to atmospheric aerosol particles.

    PubMed

    Caggiano, Rosa; Calamita, Giuseppe; Sabia, Serena; Trippetta, Serena

    2017-02-13

    The investigation of the potential natural and anthropogenic contribution to atmospheric aerosol particles by using lichen-bag technique was performed in the Agri Valley (Basilicata region, southern Italy). This is an area of international concern since it houses one of the largest European on-shore reservoirs and the biggest oil/gas pre-treatment plant (i.e., Centro Olio Val d'Agri (COVA)) within an anthropized context. In particular, the concentrations of 17 trace elements (Al, Ca, Cd, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, Pb, S, Ti, and Zn) were measured in lichen bags exposed in 59 selected monitoring points over periods of 6 months (from October 2011 to April 2012) and 12 months (from October 2011 to October 2012). The general origin of the main air masses affecting the sampling site during the study period was assessed by the back trajectories clustering calculated using the HYbrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. The results allowed the identification and characterization of the crustal material, smoke, sea salt, sulfate, and anthropogenic trace element contributions to the atmospheric aerosol particles in the study area. Finally, the application of the trend surface analysis (TSA) allowed the study of the spatial distribution of the considered contributions highlighting the existence of a continuous broad variation of these contributions in the area of interest.

  14. Rain pH estimation based on the particulate matter pollutants and wet deposition study.

    PubMed

    Singh, Shweta; Elumalai, Suresh Pandian; Pal, Asim Kumar

    2016-09-01

    In forecasting of rain pH, the changes caused by particulate matter (PM) are generally neglected. In regions of high PM concentration like Dhanbad, the role of PM in deciding the rain pH becomes important. Present work takes into account theoretical prediction of rain pH by two methods. First method considers only acid causing gases (ACG) like CO2, SO2 and NOx in pH estimation, whereas, second method additionally accounts for effect of PM (ACG-PM). In order to predict the rain pH, site specific deposited dust that represents local PM was studied experimentally for its impact on pH of neutral water. After incorporation of PM correction factor, it was found that, rain pH values estimated were more representative of the observed ones. Fractional bias (FB) for the ACG-PM method reduced to values of the order of 10(-2) from those with order of 10(-1) for the ACG method. The study confirms neutralization of rain acidity by PM. On account of this, rain pH was found in the slightly acidic to near neutral range, despite of the high sulfate flux found in rain water. Although, the safer range of rain pH blurs the severity of acid rain from the picture, yet huge flux of acidic and other ions get transferred to water bodies, soil and ultimately to the ground water system. Simple use of rain pH for rain water quality fails to address the issues of its increased ionic composition due to the interfering pollutants and thus undermines severity of pollutants transferred from air to rain water and then to water bodies and soil.

  15. Adjoint-Based Methods for Estimating CO2 Sources and Sinks from Atmospheric Concentration Data

    NASA Technical Reports Server (NTRS)

    Andrews, Arlyn E.

    2003-01-01

    Work to develop adjoint-based methods for estimating CO2 sources and sinks from atmospheric concentration data was initiated in preparation for last year's summer institute on Carbon Data Assimilation (CDAS) at the National Center for Atmospheric Research in Boulder, CO. The workshop exercises used the GSFC Parameterized Chemistry and Transport Model and its adjoint. Since the workshop, a number of simulations have been run to evaluate the performance of the model adjoint. Results from these simulations will be presented, along with an outline of challenges associated with incorporating a variety of disparate data sources, from sparse, but highly precise, surface in situ observations to less accurate, global future satellite observations.

  16. Horizontal Advection and Mixing of Pollutants in the Urban Atmospheric Environment

    NASA Astrophysics Data System (ADS)

    Magnusson, S. P.; Entekhabi, D.; Britter, R.; Norford, L.; Fernando, H. J.

    2013-12-01

    Although urban air quality and its impacts on the public health have long been studied, the increasing urbanization is raising concerns on how to better control and mitigate these health impacts. A necessary element in predicting exposure levels is fundamental understanding of flow and dispersion in urban canyons. The complex topology of building structures and roads requires the resolution of turbulence phenomena within urban canyons. The use of dense and low porosity construction material can lead to rapid heating in response to direct solar exposure due to large thermal mass. Hence thermal and buoyancy effects may be as important as mechanically-forced or shear-induced flows. In this study, the transport of pollutants within the urban environment, as well as the thermal and advection effects, are investigated. The focus is on the horizontal transport or the advection effects within the urban environment. With increased urbanization and larger and more spread cities, concern about how the upstream air quality situation can affect downstream areas. The study also examines the release and the dispersion of hazardous material. Due to the variety and complexity of urban areas around the world, the urban environment is simplified into adjacent two-dimensional urban street canyons. Pollutants are released inside each canyon. Computational Fluid Dynamics (CFD) simulations are applied to evaluate and quantify the flow rate out of each canyon and also the exchange of pollutants between the canyons. Imagine a row of ten adjacent urban street canyons of aspect ratio 1 with horizontal flow perpendicular to it as shown in the attached figure. C is the concentration of pollutants. The first digit indicates in what canyon the pollutant is released and the second digit indicates the location of that pollutant. For example, C3,4 is the concentration of pollutant released inside canyon 3 measured in canyon 4. The same amount of pollution is released inside the ten street canyons

  17. Atmospheric pollution problems and control proposals associated with solid waste management in China: a review.

    PubMed

    Tian, Hezhong; Gao, Jiajia; Hao, Jiming; Lu, Long; Zhu, Chuanyong; Qiu, Peipei

    2013-05-15

    Along with population growth, rapid urbanization and industrialization process, the volume of municipal solid waste (MSW) generation in China has been increasing sharply in the past 30 years and the total amount of MSW yields will continue to increase. Nowadays, due to global warming warrants particular attention throughout the world, a series of air pollutants (including greenhouse gases, odorous gases, PCDD/Fs, heavy metals, PM, etc.) discharged from waste disposal and treatment processes have become one of the new significant emerging air pollution sources, which arousing great concerns about their adverse effects on surrounding ambient air quality and public health. At present, the overall safely disposed ratio of the collected MSW in China is reported at approximately 78% in 2010, and there are mainly three types of MSW disposal methods practiced in China, including landfill, composting and incineration. The characteristics of air pollutants and greenhouse gases discharge vary substantially among different MSW disposal methods. By presenting a thorough review of MSW generation in China and providing a summarization of the current status of MSW disposal methods practices, this review article makes an integrated overview analysis of existing air pollution problems associated with MSW collection, separation, and disposal processes. Furthermore, some comprehensive control proposals to prevent air pollution for improving MSW management of China in the future are put forward.

  18. 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.

  19. Limitation of Ground-based Estimates of Solar Irradiance Due to Atmospheric Variations

    NASA Technical Reports Server (NTRS)

    Wen, Guoyong; Cahalan, Robert F.; Holben, Brent N.

    2003-01-01

    The uncertainty in ground-based estimates of solar irradiance is quantitatively related to the temporal variability of the atmosphere's optical thickness. The upper and lower bounds of the accuracy of estimates using the Langley Plot technique are proportional to the standard deviation of aerosol optical thickness (approx. +/- 13 sigma(delta tau)). The estimates of spectral solar irradiance (SSI) in two Cimel sun photometer channels from the Mauna Loa site of AERONET are compared with satellite observations from SOLSTICE (Solar Stellar Irradiance Comparison Experiment) on UARS (Upper Atmospheric Research Satellite) for almost two years of data. The true solar variations related to the 27-day solar rotation cycle observed from SOLSTICE are about 0.15% at the two sun photometer channels. The variability in ground-based estimates is statistically one order of magnitude larger. Even though about 30% of these estimates from all Level 2.0 Cimel data fall within the 0.4 to approx. 0.5% variation level, ground-based estimates are not able to capture the 27-day solar variation observed from SOLSTICE.

  20. 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

  1. Biomonitoring of atmospheric pollution by moss bags: Discriminating urban-rural structure in a fragmented landscape.

    PubMed

    Capozzi, F; Giordano, S; Di Palma, A; Spagnuolo, V; De Nicola, F; Adamo, P

    2016-04-01

    In this paper we investigated the possibility to use moss bags to detect pollution inputs - metals, metalloids and polycyclic aromatic hydrocarbons (PAHs) - in sites chosen for their different land use (agricultural, urban/residential scenarios) and proximity to roads (sub-scenarios), in a fragmented conurbation of Campania (southern Italy). We focused on thirty-nine elements including rare earths. For most of them, moss uptake was higher in agricultural than in urban scenarios and in front road sites. Twenty PAHs were analyzed in a subset of agricultural sites; 4- and 5-ringed PAHs were the most abundant, particularly chrysene, fluoranthene and pyrene. Overall results indicated that investigated pollutants have a similar spatial distribution pattern over the entire study area, with road traffic and agricultural practices as the major diffuse pollution sources. Moss bags proved a very sensitive tool, able to discriminate between different land use scenarios and proximity to roads in a mixed rural-urban landscape.

  2. Impacts of atmospheric pollution on the plant communities of British acid grasslands.

    PubMed

    Payne, Richard J; Stevens, Carly J; Dise, Nancy B; Gowing, David J; Pilkington, Michael G; Phoenix, Gareth K; Emmett, Bridget A; Ashmore, Michael R

    2011-10-01

    Air pollutants are recognised as important agents of ecosystem change but few studies consider the effects of multiple pollutants and their interactions. Here we use ordination, constrained cluster analysis and indicator value analyses to identify potential environmental controls on species composition, ecological groupings and indicator species in a gradient study of UK acid grasslands. The community composition of these grasslands is related to climate, grazing, ozone exposure and nitrogen deposition, with evidence for an interaction between the ecological impacts of base cation and nitrogen deposition. Ozone is a key agent in species compositional change but is not associated with a reduction in species richness or diversity indices, showing the subtly different drivers on these two aspects of ecosystem degradation. Our results demonstrate the effects of multiple interacting pollutants, which may collectively have a greater impact than any individual agent.

  3. Contribution of atmospheric nitrogen deposition to diffuse pollution in a typical hilly red soil catchment in southern China.

    PubMed

    Shen, Jianlin; Liu, Jieyun; Li, Yong; Li, Yuyuan; Wang, Yi; Liu, Xuejun; Wu, Jinshui

    2014-09-01

    Atmospheric nitrogen (N) deposition is currently high and meanwhile diffuse N pollution is also serious in China. The correlation between N deposition and riverine N export and the contribution of N deposition to riverine N export were investigated in a typical hilly red soil catchment in southern China over a two-year period. N deposition was as high as 26.1 to 55.8kgN/(ha·yr) across different land uses in the studied catchment, while the riverine N exports ranged from 7.2 to 9.6kgN/(ha·yr) in the forest sub-catchment and 27.4 to 30.3kgN/(ha·yr) in the agricultural sub-catchment. The correlations between both wet N deposition and riverine N export and precipitation were highly positive, and so were the correlations between NH4(+)-N or NO3(-)-N wet deposition and riverine NH4(+)-N or NO3(-)-N exports except for NH4(+)-N in the agricultural sub-catchment, indicating that N deposition contributed to riverine N export. The monthly export coefficients of atmospheric deposited N from land to river in the forest sub-catchment (with a mean of 14%) presented a significant positive correlation with precipitation, while the monthly contributions of atmospheric deposition to riverine N export (with a mean of 18.7% in the agricultural sub-catchment and a mean of 21.0% in the whole catchment) were significantly and negatively correlated with precipitation. The relatively high contribution of N deposition to diffuse N pollution in the catchment suggests that efforts should be done to control anthropogenic reactive N emissions to the atmosphere in hilly red soil regions in southern China.

  4. Monitoring of air pollution in the atmosphere around Oman Liquid Natural Gas (OLNG) plant.

    PubMed

    Abdul-Wahab, Sabah A

    2005-01-01

    This study was basically designed to assess the potential environmental air quality impacts arising from the existing two operational trains at the Oman Liquid Natural Gas (OLNG) plant. The results of the paper contain a baseline survey of the existing environment. The pollutants studied included methane (CH4), non-methane hydrocarbons (NMHC), carbon monoxide (CO), nitrogen oxides (NOx), and suspended particulate matters (dust PM 10). Meteorological parameters monitored simultaneously include wind speed and direction, air temperature, and relative humidity. The air quality data were used to determine the diurnal and monthly variations in the pollutants. Description levels of the pollutants with respect to meteorological data were also used in analysis. Moreover, a statistical analysis of the collected data was presented. Generally, the results indicated that the mean concentrations of pollutants were low to cause any significant impact in air quality. The area had no problem in meeting the air quality standards for CO and NO2. It was also found that there was a random relationship between CO and NMHC, and between NO and NOx (no apparent correlation). The diurnal peaks of NOx, NO2, THC, and NMHC over a 24-h period were observed at around 9:00-10:00 AM (morning peak). For NO, NO2, and NOx, another peak was seen at around 5:00 PM (evening peak). Furthermore, the measured concentrations for NO2, NOx, and CO were found higher in winter than in summer. The study would help to gain a better understanding of local background levels of air pollutants at the area prior to the construction of new industrial projects, and to prepare action plans for controlling pollution in the area.

  5. Estimating Bacteria Emissions from Inversion of Atmospheric Transport: Sensitivity to Modelled Particle Characteristics

    SciTech Connect

    Burrows, Susannah M.; Rayner, Perter; Butler, T.; Lawrence, M.

    2013-06-04

    Model-simulated transport of atmospheric trace components can be combined with observed concentrations to obtain estimates of ground-based sources using various inversion techniques. These approaches have been applied in the past primarily to obtain source estimates for long-lived trace gases such as CO2. We consider the application of similar techniques to source estimation for atmospheric aerosols, by using as a case study the estimation of bacteria emissions from different ecosystem regions in the global atmospheric chemistry and climate model ECHAM5/MESSy-Atmospheric Chemistry (EMAC). Simulated particle concentrations in the tropopause region and at high latitudes, as well as transport of particles to tundra and land ice regions are shown to be highly sensitive to scavenging in mixed-phase clouds, which is poorly characterized in most global climate models. This may be a critical uncertainty in correctly simulating the transport of aerosol particles to the Arctic. Source estimation via Monte Carlo Markov Chain is applied to a suite of sensitivity simulations and the global mean emissions are estimated. We present an analysis of the partitioning of uncertainties in the global mean emissions that are attributable to particle size, CCN activity, the ice nucleation scavenging ratios for mixed-phase and cold clouds, and measurement error. Uncertainty due to CCN activity or to a 1 um error in particle size is typically between 10% and 40% of the uncertainty due to data uncertainty, as measured by the 5%-ile to 95%-ile range of the Monte Carlo ensemble. Uncertainty attributable to the ice nucleation scavenging ratio in mized-phase clouds is as high as 10% to 20% of the data uncertainty. Taken together, the four model 20 parameters examined contribute about half as much to the uncertainty in the estimated emissions as do the measurements. This was a surprisingly large contribution from model uncertainty in light of the substantial data uncertainty, which ranges from 81

  6. Radar Estimations of Atmospheric Winds in the Troposphere and Lower Stratosphere

    NASA Astrophysics Data System (ADS)

    Sheppard, Emory Lamar

    This dissertation deals with the estimation of atmospheric flow field parameters using the spaced antenna (SA) and spatial interferometer (SI) methods. In the first section, a computer simulation of scattering from inhomogeneities in the refractive index is used to compare the SA and SI methods for measuring winds in clear air both with and without turbulent fading. The results show that the SA analysis which is carried out in the time domain and the SI analysis which is carried out in the frequency domain are equivalent in terms of the information that the two methods yield. A data analysis method equivalent to full correlation analysis, which can be carried out in the frequency domain, is presented. The method is applied to model-generated data in order to extract the typical full correlation analysis output parameters such as the apparent and true velocities. The results obtained are consistent with the model input parameters. In the second section a statistical comparison of the SA and SI methods for estimating horizontal winds in the troposphere and the lower stratosphere is presented. The data analyzed were obtained with the Middle and Upper (MU) atmosphere radar from 1910 LT on June 29, 1990, through 0950 LT on July 2, 1990. At all heights, velocity estimates based on frequency domain data are within 4% of those based on time domain data. We conclude that frequency domain techniques provide an alternate method for estimating true horizontal velocity. Nevertheless, it is not clear that they offer any significant advantage over time domain methods. In fact, the results obtained indicate that the SI method for estimating horizontal velocity may be slightly more difficult to apply in practice. The final section presents an analytical evaluation of SA-based instrumental setups with the potential for estimating the vertical component of atmospheric vorticity from a single-radar location. Methods considered are the oblique spaced antenna (OAS) method and a modified

  7. Correcting atmospheric effects in thermal ground observations for hyperspectral emissivity estimation

    NASA Astrophysics Data System (ADS)

    Timmermans, Joris; Buitrago, Maria

    2014-05-01

    Knowledge of Land surface temperature is of crucial importance in energy balance studies and environmental modeling. Accurate retrieval of land surface temperature (LST) demands detailed knowledge of the land surface emissivity. Measured radiation by remote sensing sensors to land surface temperature can only be performed using a-priori knowledge of the emissivity. Uncertainties in the retrieval of this emissivity can cause huge errors in LST estimations. The retrieval of emissivity (and LST) is per definition an underdetermined inversion, as only one observation is made while two variables are to be estimated. Several researches have therefore been performed on measuring emissivity, such as the normalized emissivity method, the temperature-emissivity separation (TES) using the minimum and maximum difference of emissivity and the use of vegetation indices. In each of these approaches atmospherically corrected radiance measurements by remote sensing sensors are correlated to ground measurements. Usually these ground measurements are performed with the ground equivalent of the remote sensing sensors; the CIMEL 312-2 has the same spectral bands as ASTER. This way parameterizations acquired this way are only usable for specific sensors and need to be redone for newer sensors. Recently hyperspectral thermal radiometers, such as the MIDAC, have been developed that can solve this problem. By using hyperspectral observations of emissivity, together with sensor simulators, ground measurements of different satellite sensor can be simulated. This facilitates the production of validation data for the different TES algorithms. However before such measurements can be performed extra steps of processing need to be performed. Atmospheric correction becomes more important in hyperspectral observations than for broadband observations, as energy levels measured per band is lower. As such the atmosphere has a relative larger contribution if bandwidths become smaller. The goal of this

  8. A Green Planet versus a Desert World: Estimating the Effect of Vegetation Extremes on the Atmosphere.

    NASA Astrophysics Data System (ADS)

    Fraedrich, Klaus; Kleidon, Axel; Lunkeit, Frank

    1999-10-01

    The effect of vegetation extremes on the general circulation is estimated by two atmospheric GCM simulations using global desert and forest boundary conditions over land. The difference between the climates of a `green planet' and a `desert world' is dominated by the changes of the hydrological cycle, which is intensified substantially. Enhanced evapotranspiration over land reduces the near-surface temperatures; enhanced precipitation leads to a warmer mid- and upper troposphere extending from the subtropics (induced by ITCZ, monsoon, and Hadley cell dynamics) to the midlatitudes (over the cyclogenesis area of Northern Hemisphere storm tracks). These regional changes of the surface water and energy balances, and of the atmospheric circulation, have potential impact on the ocean and the atmospheric greenhouse.

  9. Part 3. Estimating the effects of air pollution on mortality in Bangkok, Thailand.

    PubMed

    Vichit-Vadakan, Nuntavarn; Vajanapoom, Nitaya; Ostro, Bart

    2010-11-01

    While the effects of particulate matter (PM*) on mortality have been well documented in North America and Western Europe, considerably less is known about its effects in developing countries in Asia. Existing air pollution data in Bangkok, Thailand, indicate that airborne concentrations of PM < or = 10 pm in aerodynamic diameter (PM10) are as high or higher than those experienced in most cities in North America and Western Europe. At the same time, the demographics, activity patterns, and background health status of the population, as well as the chemical composition of PM, are different in Bangkok. It is important, therefore, to determine whether the effects of PM10 on mortality occurring in this large metropolitan area are similar to those in Western cities. The quality and completeness of Bangkok mortality data have been recently enhanced by the completion of a few mortality studies and through input from monitors currently measuring daily PM10 in Bangkok. In this analysis, we examined the effects of PM10 and several gaseous pollutants on daily mortality for the years 1999 through 2003. Our results suggest strong associations between several different mortality outcomes and levels of PM10 and several of the gaseous pollutants, including nitrogen dioxide (NO2), nitric oxide (NO), and ozone (O3). In many cases, the effect estimates were higher than the approximately 6% per 10 microg/m3 typically reported in Western industrialized nations-based on reviews by the U.S. Environmental Protection Agency (U.S. EPA) and the World Health Organization (WHO) (Anderson et al. 2004). For example, the excess risk (ER) for mortality due to all natural causes was 1.3% (95% confidence interval [CI], 0.8 to 1.7), with higher ERs for cardiovascular and respiratory mortality of 1.9% (95% CI, 0.8 to 3.0) and 1.0% (95% CI, -0.4 to 2.4), respectively. Of particular note, for this warm, tropical city of approximately 6 to 10 million people, is that there is no covariation between

  10. State and Parameter Estimation for a Coupled Ocean--Atmosphere Model

    NASA Astrophysics Data System (ADS)

    Ghil, M.; Kondrashov, D.; Sun, C.

    2006-12-01

    The El-Nino/Southern-Oscillation (ENSO) dominates interannual climate variability and plays, therefore, a key role in seasonal-to-interannual prediction. Much is known by now about the main physical mechanisms that give rise to and modulate ENSO, but the values of several parameters that enter these mechanisms are an important unknown. We apply Extended Kalman Filtering (EKF) for both model state and parameter estimation in an intermediate, nonlinear, coupled ocean--atmosphere model of ENSO. The coupled model consists of an upper-ocean, reduced-gravity model of the Tropical Pacific and a steady-state atmospheric response to the sea surface temperature (SST). The model errors are assumed to be mainly in the atmospheric wind stress, and assimilated data are equatorial Pacific SSTs. Model behavior is very sensitive to two key parameters: (i) μ, the ocean-atmosphere coupling coefficient between SST and wind stress anomalies; and (ii) δs, the surface-layer coefficient. Previous work has shown that δs determines the period of the model's self-sustained oscillation, while μ measures the degree of nonlinearity. Depending on the values of these parameters, the spatio-temporal pattern of model solutions is either that of a delayed oscillator or of a westward propagating mode. Estimation of these parameters is tested first on synthetic data and allows us to recover the delayed-oscillator mode starting from model parameter values that correspond to the westward-propagating case. Assimilation of SST data from the NCEP-NCAR Reanalysis-2 shows that the parameters can vary on fairly short time scales and switch between values that approximate the two distinct modes of ENSO behavior. Rapid adjustments of these parameters occur, in particular, during strong ENSO events. Ways to apply EKF parameter estimation efficiently to state-of-the-art coupled ocean--atmosphere GCMs will be discussed.

  11. Constraining Methane Flux Estimates Using Atmospheric Observations of Methane and 1^3C in Methane

    NASA Astrophysics Data System (ADS)

    Mikaloff Fletcher, S. E.; Tans, P. P.; Miller, J. B.; Bruhwiler, L. M.

    2002-12-01

    Understanding the budget of methane is crucial to predicting climate change and managing earth's carbon reservoirs. Methane is responsible for approximately 15% of the anthropogenic greenhouse forcing and has a large impact on the oxidative capacity of Earth's atmosphere due to its reaction with hydroxyl radical. At present, many of the sources and sinks of methane are poorly understood due in part to the large spatial and temporal variability of the methane flux. Model simulations of methane mixing ratios using most process-based source estimates typically over-predict the latitudinal gradient of atmospheric methane relative to the observations; however, the specific source processes responsible for this discrepancy have not been identified definitively. The aim of this work is to use the isotopic signatures of the sources to attribute these discrepancies to a source process or group of source processes and create global and regional budget estimates that are in agreement with both the atmospheric observations of methane and 1^3C in methane. To this end, observations of isotopic ratios of 1^3C in methane and isotopic signatures of methane source processes are used in conjunction with an inverse model of the methane budget. Inverse modeling is a top-down approach which uses observations of trace gases in the atmosphere, an estimate of the spatial pattern of trace gas fluxes, and a model of atmospheric transport to estimate the sources and sinks. The atmospheric transport was represented by the TM3 three-dimensional transport model. The GLOBALVIEW 2001 methane observations were used along with flask measurements of 1^3C in methane at six of the CMDL-NOAA stations by INSTAAR. Initial results imply interesting differences from previous methane budget estimates. For example, the 1^3C isotope observations in methane call for an increase in southern hemisphere sources with a bacterial isotopic signature such as wetlands, rice paddies, termites, and ruminant animals. The

  12. Estimating the Pollution Risk of Cadmium in Soil Using a Composite Soil Environmental Quality Standard

    PubMed Central

    Huang, Biao; Zhao, Yongcun

    2014-01-01

    Estimating standard-exceeding probabilities of toxic metals in soil is crucial for environmental evaluation. Because soil pH and land use types have strong effects on the bioavailability of trace metals in soil, they were taken into account by some environmental protection agencies in making composite soil environmental quality standards (SEQSs) that contain multiple metal thresholds under different pH and land use conditions. This study proposed a method for estimating the standard-exceeding probability map of soil cadmium using a composite SEQS. The spatial variability and uncertainty of soil pH and site-specific land use type were incorporated through simulated realizations by sequential Gaussian simulation. A case study was conducted using a sample data set from a 150 km2 area in Wuhan City and the composite SEQS for cadmium, recently set by the State Environmental Protection Administration of China. The method may be useful for evaluating the pollution risks of trace metals in soil with composite SEQSs. PMID:24672364

  13. Estimating the pollution risk of cadmium in soil using a composite soil environmental quality standard.

    PubMed

    Qu, Mingkai; Li, Weidong; Zhang, Chuanrong; Huang, Biao; Zhao, Yongcun

    2014-01-01

    Estimating standard-exceeding probabilities of toxic metals in soil is crucial for environmental evaluation. Because soil pH and land use types have strong effects on the bioavailability of trace metals in soil, they were taken into account by some environmental protection agencies in making composite soil environmental quality standards (SEQSs) that contain multiple metal thresholds under different pH and land use conditions. This study proposed a method for estimating the standard-exceeding probability map of soil cadmium using a composite SEQS. The spatial variability and uncertainty of soil pH and site-specific land use type were incorporated through simulated realizations by sequential Gaussian simulation. A case study was conducted using a sample data set from a 150 km(2) area in Wuhan City and the composite SEQS for cadmium, recently set by the State Environmental Protection Administration of China. The method may be useful for evaluating the pollution risks of trace metals in soil with composite SEQSs.

  14. Economic Estimation of the Losses Caused by Surface Water Pollution Accidents in China From the Perspective of Water Bodies’ Functions

    PubMed Central

    Yao, Hong; You, Zhen; Liu, Bo

    2016-01-01

    The number of surface water pollution accidents (abbreviated as SWPAs) has increased substantially in China in recent years. Estimation of economic losses due to SWPAs has been one of the focuses in China and is mentioned many times in the Environmental Protection Law of China promulgated in 2014. From the perspective of water bodies’ functions, pollution accident damages can be divided into eight types: damage to human health, water supply suspension, fishery, recreational functions, biological diversity, environmental property loss, the accident’s origin and other indirect losses. In the valuation of damage to people’s life, the procedure for compensation of traffic accidents in China was used. The functional replacement cost method was used in economic estimation of the losses due to water supply suspension and loss of water’s recreational functions. Damage to biological diversity was estimated by recovery cost analysis and damage to environmental property losses were calculated using pollutant removal costs. As a case study, using the proposed calculation procedure the economic losses caused by the major Songhuajiang River pollution accident that happened in China in 2005 have been estimated at 2263 billion CNY. The estimated economic losses for real accidents can sometimes be influenced by social and political factors, such as data authenticity and accuracy. Besides, one or more aspects in the method might be overestimated, underrated or even ignored. The proposed procedure may be used by decision makers for the economic estimation of losses in SWPAs. Estimates of the economic losses of pollution accidents could help quantify potential costs associated with increased risk sources along lakes/rivers but more importantly, highlight the value of clean water to society as a whole. PMID:26805869

  15. Economic Estimation of the Losses Caused by Surface Water Pollution Accidents in China From the Perspective of Water Bodies' Functions.

    PubMed

    Yao, Hong; You, Zhen; Liu, Bo

    2016-01-22

    The number of surface water pollution accidents (abbreviated as SWPAs) has increased substantially in China in recent years. Estimation of economic losses due to SWPAs has been one of the focuses in China and is mentioned many times in the Environmental Protection Law of China promulgated in 2014. From the perspective of water bodies' functions, pollution accident damages can be divided into eight types: damage to human health, water supply suspension, fishery, recreational functions, biological diversity, environmental property loss, the accident's origin and other indirect losses. In the valuation of damage to people's life, the procedure for compensation of traffic accidents in China was used. The functional replacement cost method was used in economic estimation of the losses due to water supply suspension and loss of water's recreational functions. Damage to biological diversity was estimated by recovery cost analysis and damage to environmental property losses were calculated using pollutant removal costs. As a case study, using the proposed calculation procedure the economic losses caused by the major Songhuajiang River pollution accident that happened in China in 2005 have been estimated at 2263 billion CNY. The estimated economic losses for real accidents can sometimes be influenced by social and political factors, such as data authenticity and accuracy. Besides, one or more aspects in the method might be overestimated, underrated or even ignored. The proposed procedure may be used by decision makers for the economic estimation of losses in SWPAs. Estimates of the economic losses of pollution accidents could help quantify potential costs associated with increased risk sources along lakes/rivers but more importantly, highlight the value of clean water to society as a whole.

  16. Atmospheric channel transfer function estimation from experimental free-space optical communications data

    NASA Astrophysics Data System (ADS)

    Reinhardt, Colin N.; Kuga, Yasuo; Ritcey, James A.; Ishimaru, Akira; Hammel, Stephen; Tsintikidis, Dimitris

    2011-09-01

    The performance of terrestrial free-space optical communications systems is severely impaired by atmospheric aerosol particle distributions where the particle size is on the order of the operating wavelength. For optical and near-infrared wavelengths, fog droplets cause multiple-scattering and absorption effects which rapidly degrade received symbol detection performance as the optical depth parameter increases (visibility decreases). Using a custom free-space optical communications system we measured field data in fog within the optical multiple-scattering regime. We investigate the behavior of the estimated channel transfer function using both real field-test data and simulated propagation data based on field-test conditions. We then compare the channel transfer function estimates against the predictions computed using a radiative-transfer theory model-based approach which we also developed previously for the free-space optical atmospheric channel.

  17. Geodesy by radio interferometry - Effects of atmospheric modeling errors on estimates of baseline length

    NASA Technical Reports Server (NTRS)

    Davis, J. L.; Herring, T. A.; Shapiro, I. I.; Rogers, A. E. E.; Elgered, G.

    1985-01-01

    Analysis of very long baseline interferometry data indicates that systematic errors in prior estimates of baseline length, of order 5 cm for approximately 8000-km baselines, were due primarily to mismodeling of the electrical path length of the troposphere and mesosphere ('atmospheric delay'). Here observational evidence for the existence of such errors in the previously used models for the atmospheric delay is discussed, and a new 'mapping' function for the elevation angle dependence of this delay is developed. The delay predicted by this new mapping function differs from ray trace results by less than approximately 5 mm, at all elevations down to 5 deg elevation, and introduces errors into the estimates of baseline length of less than about 1 cm, for the multistation intercontinental experiment analyzed here.

  18. Accurate group velocity estimation for unmanned aerial vehicle-based acoustic atmospheric tomography.

    PubMed

    Rogers, Kevin J; Finn, Anthony

    2017-02-01

    Acoustic atmospheric tomography calculates temperature and wind velocity fields in a slice or volume of atmosphere based on travel time estimates between strategically located sources and receivers. The technique discussed in this paper uses the natural acoustic signature of an unmanned aerial vehicle as it overflies an array of microphones on the ground. The sound emitted by the aircraft is recorded on-board and by the ground microphones. The group velocities of the intersecting sound rays are then derived by comparing these measurements. Tomographic inversion is used to estimate the temperature and wind fields from the group velocity measurements. This paper describes a technique for deriving travel time (and hence group velocity) with an accuracy of 0.1% using these assets. This is shown to be sufficient to obtain highly plausible tomographic inversion results that correlate well with independent SODAR measurements.

  19. Automobile air pollution: Atmospheric motion. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1995-03-01

    The bibliography contains citations concerning the modeling, diffusion, and motion of motor vehicle exhaust. The citations cover the prediction of pollution from motor vehicles at specific locations and its impact at locations removed from the source. (Contains a minimum of 226 citations and includes a subject term index and title list.)

  20. Automobile air pollution: Atmospheric motion. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1996-05-01

    The bibliography contains citations concerning the modeling, diffusion, and motion of motor vehicle exhaust. The citations cover the prediction of pollution from motor vehicles at specific locations and its impact at locations removed from the source. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  1. New Model Provides Estimates for Global Disease Burdens from Air Pollution

    EPA Pesticide Factsheets

    Air pollution has become a part of modern living. Fine PM2.5 air pollution, caused by things like automobiles, power plants, wood burning and industrial processes has been linked to cardiovascular disease, lung cancer and other diseases.

  2. Research Review: Walter Orr Roberts on the Atmosphere, Global Pollution and Weather Modification

    ERIC Educational Resources Information Center

    Jacobsen, Sally

    1973-01-01

    Global Atmospheric Research Program is envisaged to study various aspects of the environment for the whole globe. Describes programs undertaken and the international problems involved in implementing results of such research on a global level. (PS)

  3. Biomonitoring of atmospheric pollution with heavy metals in the copper mine vicinity located near Radovis, Republic of Macedonia.

    PubMed

    Balabanova, Biljana; Stafilov, Trajce; Baceva, Katerina; Sajn, Robert

    2010-10-01

    This investigation was undertaken to determine the atmospheric pollution with heavy metals due to copper mining Bucim near Radovis, the Republic of Macedonia. Moss samples (Hyloconium splendens and Pleurozium schrebery) were used for biomonitoring the possible atmospheric pollution with heavy metals in mine vicinity. Sixteen elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mn, Na, Ni, Pb, Sr, and Zn) were analysed by application of flame and electrothermal atomic absorption spectrometry (FAAS and ETAAS) and atomic emission spectrometry with inductively coupled plasma (ICP-AES). The obtained values were statistically processed using nonparametric and parametric analysis. The median value for copper obtained from moss samples (10 mg kg(-1)) was much lower compared with the same values for the whole territory of the Republic of Macedonia (22 mg kg(-1)). The range of values (2.1-198 mg kg(-1)) shows much higher content of this element in the samples taken from the study area compared to the appropriate values for the whole territory of Macedonia. The association of elements As, Cd, Cu, Fe, Pb, and Zn was singled out by factor analysis as a characteristic anthropogenic group of elements. Maps of area deposition were made for this group of elements, wherefrom correlation of these anthropogenic born elements was confirmed.

  4. Sea ice-atmospheric interaction: Application of multispectral satellite data in polar surface energy flux estimates

    NASA Technical Reports Server (NTRS)

    Steffen, Konrad; Key, J.; Maslanik, J.; Schweiger, A.

    1993-01-01

    This is the third annual report on: Sea Ice-Atmosphere Interaction - Application of Multispectral Satellite Data in Polar Surface Energy Flux Estimates. The main emphasis during the past year was on: radiative flux estimates from satellite data; intercomparison of satellite and ground-based cloud amounts; radiative cloud forcing; calibration of the Advanced Very High Resolution Radiometer (AVHRR) visible channels and comparison of two satellite derived albedo data sets; and on flux modeling for leads. Major topics covered are arctic clouds and radiation; snow and ice albedo, and leads and modeling.

  5. Lead and cadmium phytoavailability and human bioaccessibility for vegetables exposed to soil or atmospheric pollution by process ultrafine particles.

    PubMed

    Xiong, Tiantian; Leveque, Thibault; Shahid, Muhammad; Foucault, Yann; Mombo, Stéphane; Dumat, Camille

    2014-09-01

    When plants are exposed to airborne particles, they can accumulate metals in their edible portions through root or foliar transfer. There is a lack of knowledge on the influence of plant exposure conditions on human bioaccessibility of metals, which is of particular concern with the increase in urban gardening activities. Lettuce, radish, and parsley were exposed to metal-rich ultrafine particles from a recycling factory via field atmospheric fallouts or polluted soil. Total lead (Pb) and cadmium (Cd) concentrations in of the edible plant parts and their human bioaccessibility were measured, and Pb translocation through the plants was studied using Pb isotopic analysis. The Pb and Cd bioaccessibility measured for consumed parts of the different polluted plants was significantly higher for root exposure (70% for Pb and 89% for Cd in lettuce) in comparison to foliar exposure (40% for Pb and 69% for Cd in lettuce). The difference in metal bioaccessibility could be linked to the metal compartmentalization and speciation changes in relation to exposure conditions. Metal nature strongly influences the measured bioaccessibility: Cd presents higher bioaccessibility in comparison to Pb. In the case of foliar exposure, a significant translocation of Pb from leaves toward the roots was observed. To conclude, the type of pollutant and the method of exposure significantly influences the phytoavailability and human bioaccessibility of metals, especially in relation to the contrasting phenomena involved in the rhizosphere and phyllosphere. The conditions of plant exposure must therefore be taken into account for environmental and health risk assessment.

  6. Atmospheric pollution reduction effect and regional predicament: An empirical analysis based on the Chinese provincial NOx emissions.

    PubMed

    Ding, Lei; Liu, Chao; Chen, Kunlun; Huang, Yalin; Diao, Beidi

    2017-03-09

    Atmospheric pollution emissions have become a matter of public concern in recent years. However, most of the existing researches on NOx pollution are from the natural science and technology perspective, few studies have been conducted from an economic point, and regional differences have not been given adequate attention. This paper adopts provincial panel data from 2006 to 2013 and the LMDI model to analyze the key driving factors and regional dilemmas of NOx emissions. The results show that significant regional disparities still exit on NOx emissions and its reduction effect 27 provinces didn't accomplish their corresponding reduction targets. Economic development factor is the dominating driving factor of NOx emissions during the study period, while energy efficiency and technology improvement factors offset total NOx emissions in the majority of provinces. In addition, the industrial structure factor plays a more significant role in reducing the NOx emissions after 2011. Therefore, the government should consider all these factors as well as regional heterogeneity in developing appropriate pollution mitigating policies. It's necessary to change NOx emissions control attitude from original key areas control to divided-zone control, not only attaches great importance to the reduction of the original key areas, but also emphasizes the new potential hotspots with high NOx emissions.

  7. Resonance Raman imaging as a tool to assess the atmospheric pollution level: carotenoids in Lecanoraceae lichens as bioindicators.

    PubMed

    Ibarrondo, I; Prieto-Taboada, N; Martínez-Arkarazo, I; Madariaga, J M

    2016-04-01

    Raman spectroscopy differentiation of carotenoids has traditionally been based on the ν 1 position (C = C stretching vibrations in the polyene chain) in the 1500-1600 cm(-1) range, using a 785 nm excitation laser. However, when the number of conjugated double bonds is similar, as in the cases of zeaxanthin and β-carotene, this distinction is still ambiguous due to the closeness of the Raman bands. This work shows the Raman results, obtained in resonance conditions using a 514 mm laser, on Lecanora campestris and Lecanora atra species, which can be used to differentiate and consequently characterize carotenoids. The presence of the carotenoid found in Lecanoraceae lichens has been demonstrated to depend on the atmospheric pollution level of the environment they inhabit. Astaxanthin, a superb antioxidant, appears as the principal xanthophyll in highly polluted sites, usually together with the UV screening pigment scytonemin; zeaxanthin is the major carotenoid in medium polluted environments, while β-carotene is the major carotenoid in cleaner environments. Based on these observations, an indirect classification of the stress suffered in a given environment can be assessed by simply analysing the carotenoid content in the Lecanoraceae lichens by using resonance Raman imaging.

  8. Atmospheric transport of persistent organic pollutants to and from the Arctic under present-day and future climate.

    PubMed

    Octaviani, Mega; Stemmler, Irene; Lammel, Gerhard; Graf, Hans F

    2015-03-17

    The long-term atmospheric cycling and fate of persistent organic pollutants under the influence of a changing climate is a concern. A GCM's realization of present-day (1970-1999) and future (2070-2099) climate, the latter under a medium scenario of greenhouse gas emissions, is used to study meridional transports and their correlations with the Arctic and North Atlantic Oscillations (AO and NAO). Regions of import and export maxima into the Arctic are identified along the Arctic Circle. It is found that, under future climate conditions, the net export of PCB153 out of the Arctic will increase. The meridional net flux pattern of this substance is expected to become independent of AO and NAO. For DDT, a trend of decreasing net Arctic import will reverse to an increasing trend 100 years after peak emission, which is partly due to more frequent AO and NAO positive phases. It is concluded that the long-term accumulation trends in the Arctic of other persistent pollutants, including so-called emerging pollutants, are subject to the substances' specific behavior and fate in the environment and need to be studied specifically.

  9. 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.

  10. Considerations on Estimating Upper Bounds of Neutron Doses Equivalents to Military Participants at Atmospheric Nuclear Tests

    DTIC Science & Technology

    2007-04-01

    Tissue kerma for monoenergetic neutrons of energy up to 14 MeV and contributions from different interactions that produce charged ionizing particles...fluence for each energy group obtained from calculations for monoenergetic neutrons similar to calculations in Figure 2-I, and the energy dependence of the...Considerations on Estimating Upper Bounds of Neutron Dose Equivalents to Military Partici pants at Atmospheric Nuclear Tests Approved for public release

  11. Estimating Dust and Water Ice Content of the Martian Atmosphere From THEMIS Data

    NASA Technical Reports Server (NTRS)

    Bandfield, Joshua

    2007-01-01

    Researchers at JPL and Arizona State University conducted a comparative study of three candidate algorithms for estimating components of the Martian atmosphere, using raw (uncalibrated) data collected by the Thermal Emission Imaging System (THEMIS). THEMIS is an instrument onboard the Mars Odyssey spacecraft that acquires image data in five visible and nine infrared (IR) wavelength bands. The algorithms under study used data collected from eight of the nine IR bands to estimate the dust and water ice content of the atmosphere. Such an algorithm could be used in onboard data processing to trigger other algorithms that search for features of scientific interest and to reduce the volume of data transmitted to Earth. The algorithms studied were based on regression models. In the study, the optical depths estimated by these algorithms were compared with optical depths estimated in ground-based processing using fully calibrated data from both THEMIS and the Thermal Emission Spectrometer (TES). TES is an instrument onboard the Mars Global Surveyor spacecraft that also observes the planet at infrared wavelengths, but at a lower spatial resolution than THEMIS does. Of the algorithms studied, the one that performed best was based on a Gaussian Support Vector Machine regression model. The test results indicated that this algorithm, operating on the raw data, had error rates that were within the uncertainty associated with the estimates obtained by the groundbased analysis of the fully calibrated data. This level of fidelity demonstrates that these algorithms are sufficiently accurate for use in an onboard setting.

  12. Radiance and atmosphere propagation-based method for the target range estimation

    NASA Astrophysics Data System (ADS)

    Cho, Hoonkyung; Chun, Joohwan

    2012-06-01

    Target range estimation is traditionally based on radar and active sonar systems in modern combat system. However, the performance of such active sensor devices is degraded tremendously by jamming signal from the enemy. This paper proposes a simple range estimation method between the target and the sensor. Passive IR sensors measures infrared (IR) light radiance radiating from objects in dierent wavelength and this method shows robustness against electromagnetic jamming. The measured target radiance of each wavelength at the IR sensor depends on the emissive properties of target material and is attenuated by various factors, in particular the distance between the sensor and the target and atmosphere environment. MODTRAN is a tool that models atmospheric propagation of electromagnetic radiation. Based on the result from MODTRAN and measured radiance, the target range is estimated. To statistically analyze the performance of proposed method, we use maximum likelihood estimation (MLE) and evaluate the Cramer-Rao Lower Bound (CRLB) via the probability density function of measured radiance. And we also compare CRLB and the variance of and ML estimation using Monte-Carlo.

  13. CarbonTracker-CH4: an assimilation system for estimating emissions of atmospheric methane

    NASA Astrophysics Data System (ADS)

    Bruhwiler, L.; Dlugokencky, E.; Masarie, K.; Ishizawa, M.; Andrews, A.; Miller, J.; Sweeney, C.; Tans, P.; Worthy, D.

    2014-08-01

    We describe an assimilation system for atmospheric methane (CH4), CarbonTracker-CH4, and demonstrate the diagnostic value of global or zonally averaged CH4 abundances for evaluating the results. We show that CarbonTracker-CH4 is able to simulate the observed zonal average mole fractions and capture inter-annual variability in emissions quite well at high northern latitudes (53-90° N). In contrast, CarbonTracker-CH4 is less successful in the tropics where there are few observations and therefore misses significant variability and is more influenced by prior flux estimates. CarbonTracker-CH4 estimates of total fluxes at high northern latitudes are about 81 ± 7 Tg CH4 yr-1, about 12 Tg CH4 yr-1 (13%) lower than prior estimates, a result that is consistent with other atmospheric inversions. Emissions from European wetlands are decreased by 30%, a result consistent with previous work by Bergamaschi et al. (2005); however, unlike their results, emissions from wetlands in boreal Eurasia are increased relative to the prior estimate. Although CarbonTracker-CH4 does not estimate an increasing trend in emissions from high northern latitudes for 2000 through 2010, significant inter-annual variability in high northern latitude fluxes is recovered. Exceptionally warm growing season temperatures in the Arctic occurred in 2007, a year that was also anonymously wet. Estimated emissions from natural sources were greater than the decadal average by 4.4 ± 3.8 Tg CH4 yr-1 in 2007. CarbonTracker-CH4 estimates for temperate latitudes are only slightly increased over prior estimates, but about 10 Tg CH4 yr-1 is redistributed from Asia to North America. This difference exceeds the estimated uncertainty for North America (±3.5 Tg CH4 yr-1). We used time invariant prior flux estimates, so for the period from 2000 to 2006, when the growth rate of global atmospheric CH4 was very small, the assimilation does not produce increases in natural or anthropogenic emissions in contrast to bottom

  14. Estimating the effect of air pollution from a coal-fired power station on the development of children's pulmonary function.

    PubMed

    Dubnov, Jonathan; Barchana, Micha; Rishpon, Shmuel; Leventhal, Alex; Segal, Isaac; Carel, Rafael; Portnov, Boris A

    2007-01-01

    Using geographical information systems (GIS) tools, the present study analyzed the association between children's lung function development and their long-term exposure to air pollution. The study covered the cohort of 1492 schoolchildren living in the vicinity of a major coal-fired power station in the Hadera sub-district of Israel. In 1996 and 1999, the children underwent subsequent pulmonary function tests (PFT) (forced vital capacity (FVC) and forced expiratory volume during the first second (FEV(1))), and the children's parents completed a detailed questionnaire on their health status and household characteristics. A negative association was found between changes in the results of PFT and the estimated individual levels of air pollution. A sensitivity test revealed a FEV(1) decline from -4.3% for the average pollution level to -10.2% for the high air pollution level. The results of a sensitivity test for FVC were found to be similar. Association with the reported health status was found to be insignificant. As we conclude, air pollution from a coal-fired power station, although not exceeding local pollution standards, had a negative effect on children's lung function development. As argued, previous studies carried out in the region failed to show the above association because they were based on zone approaches that assign average concentration levels of air pollutants to all individuals in each zone, leading to a misclassification bias of individual exposure.

  15. Estimating European historical production, consumption and atmospheric emissions of decabromodiphenyl ether.

    PubMed

    Earnshaw, Mark R; Jones, Kevin C; Sweetman, Andy J

    2013-03-01

    A European scale production, consumption and environmental emissions inventory is produced for decabromodiphenyl ether (DecaBDE) for the period 1970-2020. A dynamic substance flow analysis model of DecaBDE is developed and emission of the main congener, BDE-209, to environmental compartments is estimated. From 1970 to 2010, it is estimated that a total of 185,000-250,000 tonnes of DecaBDE was consumed in Europe. Consumption peaked in the late 1990s at approximately 9,000 tonnes/year and has declined by ~30% in 2010. Predicted BDE-209 atmospheric emissions peak in 2004 at 10 tonnes/year. The waste management phase of the BDE-209 life cycle is responsible for the majority of atmospheric emissions via volatilisation and particle bound emissions from landfills, whilst leakage from Sewerage systems is the major source of emissions to the hydrosphere. Use of sewage sludge from wastewater treatment works as an agricultural fertiliser is the most important pathway of BDE-209 to soil. Although DecaBDE consumption has declined in recent years, the stock in use for 2010 remains considerable (60,000 tonnes) and is likely to act as a source of atmospheric emissions for several decades. Uncertainties exist in these estimations and more field or experimental data is needed to clarify the significance of certain emission pathways, in particular, emissions from landfill sites.

  16. Fluoride pollution of atmospheric precipitation and its relationship with air circulation and weather patterns (Wielkopolski National Park, Poland).

    PubMed

    Walna, Barbara; Kurzyca, Iwona; Bednorz, Ewa; Kolendowicz, Leszek

    2013-07-01

    A 2-year study (2010-2011) of fluorides in atmospheric precipitation in the open area and in throughfall in Wielkopolski National Park (west-central Poland) showed their high concentrations, reaching a maximum value of 2 mg/l under the tree crowns. These high values indicate substantial deposition of up to 52 mg/m(2)/year. In 2011, over 51% of open area precipitation was characterized by fluoride concentration higher than 0.10 mg/l, and in throughfall such concentrations were found in more than 86% of events. In 2010, a strong connection was evident between fluoride and acid-forming ions, and in 2011, a correlation between phosphate and nitrite ions was seen. Analysis of available data on F(-) concentrations in the air did not show an unequivocal effect on F(-) concentrations in precipitation. To find reasons for and source areas of high fluoride pollution, the cases of extreme fluoride concentration in rainwater were related to atmospheric circulation and weather patterns. Weather conditions on days of extreme pollution were determined by movement of weather fronts over western Poland, or by small cyclonic centers with meteorological fronts. Macroscale air advection over the sampling site originated in the western quadrant (NW, W, and SW), particularly in the middle layers of the troposphere (2,500-5,000 m a.s.l.). Such directions indicate western Poland and Germany as possible sources of the pollution. At the same time in the lower troposphere, air inflow was frequently from the north, showing short distance transport from local emitters, and from the agglomeration of Poznań.

  17. Using the soil and water assessment tool to estimate dissolved inorganic nitrogen water pollution abatement cost functions in central portugal.

    PubMed

    Roebeling, P C; Rocha, J; Nunes, J P; Fidélis, T; Alves, H; Fonseca, S

    2014-01-01

    Coastal aquatic ecosystems are increasingly affected by diffuse source nutrient water pollution from agricultural activities in coastal catchments, even though these ecosystems are important from a social, environmental and economic perspective. To warrant sustainable economic development of coastal regions, we need to balance marginal costs from coastal catchment water pollution abatement and associated marginal benefits from coastal resource appreciation. Diffuse-source water pollution abatement costs across agricultural sectors are not easily determined given the spatial heterogeneity in biophysical and agro-ecological conditions as well as the available range of best agricultural practices (BAPs) for water quality improvement. We demonstrate how the Soil and Water Assessment Tool (SWAT) can be used to estimate diffuse-source water pollution abatement cost functions across agricultural land use categories based on a stepwise adoption of identified BAPs for water quality improvement and corresponding SWAT-based estimates for agricultural production, agricultural incomes, and water pollution deliveries. Results for the case of dissolved inorganic nitrogen (DIN) surface water pollution by the key agricultural land use categories ("annual crops," "vineyards," and "mixed annual crops & vineyards") in the Vouga catchment in central Portugal show that no win-win agricultural practices are available within the assessed BAPs for DIN water quality improvement. Estimated abatement costs increase quadratically in the rate of water pollution abatement, with largest abatement costs for the "mixed annual crops & vineyards" land use category (between 41,900 and 51,900 € tDIN yr) and fairly similar abatement costs across the "vineyards" and "annual crops" land use categories (between 7300 and 15,200 € tDIN yr).

  18. Flux rates of atmospheric lead pollution within soils of a small catchment in northern Sweden and their implications for future stream water quality.

    PubMed

    Klaminder, Jonatan; Bindler, Richard; Laudon, Hjalmar; Bishop, Kevin; Emteryd, Ove; Renberg, Ingemar

    2006-08-01

    It is not well-known how the accumulated pool of atmospheric lead pollution in the boreal forest soil will affect the groundwater and surface water chemistry in the future as this lead migrates through the soil profile. This study uses stable lead isotopes (206Pb/207Pb and 208Pb/ 207Pb ratios) to trace the transport of atmospheric lead pollution within the soil of a small catchment and predict future lead level changes in a stream draining the catchment. Low 206Pb/207Pb and 208Pb/207Pb ratios for the lead in the soil water (1.16 +/- 0.02; 2.43 +/- 0.03) and streamwater (1.18 +/- 0.03; 2.42 +/- 0.03) in comparison to that of the mineral soil (>1.4; >2.5) suggest that atmospheric pollution contributes by about 90% (65-100%) to the lead pool found in these matrixes. Calculated transport rates of atmospheric lead along a soil transect indicate that the mean residence time of lead in organic and mineral soil layers is at a centennial to millennial time scale. A maximum release of the present pool of lead pollution in the soil to the stream is predicted to occur within 200-800 years. Even though the uncertainty of the prediction is large, it emphasizes the magnitude of the time lag between the accumulation of atmospheric lead pollution in soils and the subsequent response in streamwater quality.

  19. A simulation of air pollution model parameter estimation using data from a ground-based LIDAR remote sensor

    NASA Technical Reports Server (NTRS)

    Kibler, J. F.; Suttles, J. T.

    1977-01-01

    One way to obtain estimates of the unknown parameters in a pollution dispersion model is to compare the model predictions with remotely sensed air quality data. A ground-based LIDAR sensor provides relative pollution concentration measurements as a function of space and time. The measured sensor data are compared with the dispersion model output through a numerical estimation procedure to yield parameter estimates which best fit the data. This overall process is tested in a computer simulation to study the effects of various measurement strategies. Such a simulation is useful prior to a field measurement exercise to maximize the information content in the collected data. Parametric studies of simulated data matched to a Gaussian plume dispersion model indicate the trade offs available between estimation accuracy and data acquisition strategy.

  20. The model SIRANE for atmospheric urban pollutant dispersion; PART II, validation of the model on a real case study

    NASA Astrophysics Data System (ADS)

    Soulhac, L.; Salizzoni, P.; Mejean, P.; Didier, D.; Rios, I.

    2012-03-01

    We analyse the performance of the model SIRANE by comparing its outputs to field data measured within an urban district. SIRANE is the first urban dispersion model based on the concept of street network, and contains specific parametrical law to explicitly simulate the main transfer mechanisms within the urban canopy. The model validation is performed by means of field data collected during a 15 days measurement campaign in an urban district in Lyon, France. The campaign provided information on traffic fluxes and cars emissions, meteorological conditions, background pollution levels and pollutant concentration in different location within the district. This data set, together with complementary modelling tools needed to estimate the spatial distribution of traffic fluxes, allowed us to estimate the input data required by the model. The data set provide also the information essential to evaluate the accuracy of the model outputs. Comparison between model predictions and field measurements was performed in two ways. By evaluate the reliability of the model in simulating the spatial distribution of the pollutant and of their time variability. The study includes a sensitivity analysis to identify the key input parameters influencing the performance of the model, namely the emissions rates and the wind velocity. The analysis focuses only on the influence of varying input parameters in the modelling chain in the model predictions and complements the analyses provided by wind tunnel studies focussing on the parameterisation implemented in the model. The study also elucidates the critical role of background concentrations that represent a significant contribution to local pollution levels. The overall model performance, measured using the Chang and Hanna (2004) criteria can be considered as 'good' except for NO and some of BTX species. The results suggest that improvements of the performances on NO require testing new photochemical models, whereas the improvement on BTX