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Sample records for air change effectiveness

  1. Effect of Dynamic Sector Boundary Changes on Air Traffic Controllers

    NASA Technical Reports Server (NTRS)

    Jung, Jaewoo; Lee, Paul; Kessell, Angela; Homola, Jeff; Zelinski, Shannon

    2010-01-01

    The effect of dynamic sector boundary changes on air traffic controller workload was investigated with data from a human-in-the-loop simulation. Multiple boundary changes were made during simulated operations, and controller rating of workload was recorded. Analysis of these data showed an increase of 16.9% in controller workload due to boundary changes. This increased workload was correlated with the number of aircraft handoffs and change in sector volume. There was also a 12.7% increase in average workload due to the changed sector design after boundary changes. This increase was correlated to traffic flow crossing points getting closer to sector boundaries and an increase in the number of flights with short dwell time in a sector. This study has identified some of the factors that affect controller workload when sector boundaries are changed, but more research is needed to better understand their relationships.

  2. Climate Change and Air Pollution: Effects on Respiratory Allergy.

    PubMed

    D'Amato, Gennaro; Pawankar, Ruby; Vitale, Carolina; Lanza, Maurizia; Molino, Antonio; Stanziola, Anna; Sanduzzi, Alessandro; Vatrella, Alessandro; D'Amato, Maria

    2016-09-01

    A body of evidence suggests that major changes involving the atmosphere and the climate, including global warming induced by anthropogenic factors, have impact on the biosphere and human environment. Studies on the effects of climate change on respiratory allergy are still lacking and current knowledge is provided by epidemiological and experimental studies on the relationship between allergic respiratory diseases, asthma and environmental factors, such as meteorological variables, airborne allergens, and air pollution. Urbanization with its high levels of vehicle emissions, and a westernized lifestyle are linked to the rising frequency of respiratory allergic diseases and bronchial asthma observed over recent decades in most industrialized countries. However, it is not easy to evaluate the impact of climate changes and air pollution on the prevalence of asthma in the general population and on the timing of asthma exacerbations, although the global rise in asthma prevalence and severity could also be an effect of air pollution and climate change. Since airborne allergens and air pollutants are frequently increased contemporaneously in the atmosphere, an enhanced IgE-mediated response to aeroallergens and enhanced airway inflammation could account for the increasing frequency of respiratory allergy and asthma in atopic subjects in the last 5 decades. Pollen allergy is frequently used to study the relationship between air pollution and respiratory allergic diseases, such as rhinitis and bronchial asthma. Epidemiologic studies have demonstrated that urbanization, high levels of vehicle emissions, and westernized lifestyle are correlated with an increased frequency of respiratory allergy prevalently in people who live in urban areas in comparison with people living in rural areas. Climatic factors (temperature, wind speed, humidity, thunderstorms, etc.) can affect both components (biological and chemical) of this interaction.

  3. Climate Change and Air Pollution: Effects on Respiratory Allergy

    PubMed Central

    Pawankar, Ruby; Vitale, Carolina; Lanza, Maurizia; Molino, Antonio; Stanziola, Anna; Sanduzzi, Alessandro; Vatrella, Alessandro; D'Amato, Maria

    2016-01-01

    A body of evidence suggests that major changes involving the atmosphere and the climate, including global warming induced by anthropogenic factors, have impact on the biosphere and human environment. Studies on the effects of climate change on respiratory allergy are still lacking and current knowledge is provided by epidemiological and experimental studies on the relationship between allergic respiratory diseases, asthma and environmental factors, such as meteorological variables, airborne allergens, and air pollution. Urbanization with its high levels of vehicle emissions, and a westernized lifestyle are linked to the rising frequency of respiratory allergic diseases and bronchial asthma observed over recent decades in most industrialized countries. However, it is not easy to evaluate the impact of climate changes and air pollution on the prevalence of asthma in the general population and on the timing of asthma exacerbations, although the global rise in asthma prevalence and severity could also be an effect of air pollution and climate change. Since airborne allergens and air pollutants are frequently increased contemporaneously in the atmosphere, an enhanced IgE-mediated response to aeroallergens and enhanced airway inflammation could account for the increasing frequency of respiratory allergy and asthma in atopic subjects in the last 5 decades. Pollen allergy is frequently used to study the relationship between air pollution and respiratory allergic diseases, such as rhinitis and bronchial asthma. Epidemiologic studies have demonstrated that urbanization, high levels of vehicle emissions, and westernized lifestyle are correlated with an increased frequency of respiratory allergy prevalently in people who live in urban areas in comparison with people living in rural areas. Climatic factors (temperature, wind speed, humidity, thunderstorms, etc.) can affect both components (biological and chemical) of this interaction. PMID:27334776

  4. The effects of global change upon United States air quality

    NASA Astrophysics Data System (ADS)

    Gonzalez-Abraham, R.; Avise, J.; Chung, S. H.; Lamb, B.; Salathé, E. P., Jr.; Nolte, C. G.; Loughlin, D.; Guenther, A.; Wiedinmyer, C.; Duhl, T.; Zhang, Y.; Streets, D. G.

    2014-12-01

    To understand more fully the effects of global changes on ambient concentrations of ozone and particulate matter with aerodynamic diameter smaller than 2.5 μm (PM2.5) in the US, we conducted a comprehensive modeling effort to evaluate explicitly the effects of changes in climate, biogenic emissions, land use, and global/regional anthropogenic emissions on ozone and PM2.5 concentrations and composition. Results from the ECHAM5 global climate model driven with the A1B emission scenario from the Intergovernmental Panel on Climate Change (IPCC) were downscaled using the Weather Research and Forecasting (WRF) model to provide regional meteorological fields. We developed air quality simulations using the Community Multiscale Air Quality Model (CMAQ) chemical transport model for two nested domains with 220 and 36 km horizontal grid cell resolution for a semi-hemispheric domain and a continental United States (US) domain, respectively. The semi-hemispheric domain was used to evaluate the impact of projected Asian emissions changes on US air quality. WRF meteorological fields were used to calculate current (2000s) and future (2050s) biogenic emissions using the Model of Emissions of Gases and Aerosols from Nature (MEGAN). For the semi-hemispheric domain CMAQ simulations, present-day global emissions inventories were used and projected to the 2050s based on the IPCC A1B scenario. Regional anthropogenic emissions were obtained from the US Environmental Protection Agency National Emission Inventory 2002 (EPA NEI2002) and projected to the future using the MARKet ALlocation (MARKAL) energy system model assuming a business as usual scenario that extends current decade emission regulations through 2050. Our results suggest that daily maximum 8 h average ozone (DM8O) concentrations will increase in a range between 2 to 12 ppb across most of the continental US, with the highest increase in the South, Central, and Midwest regions of the US, due to increases in temperature, enhanced

  5. The effects of global change upon United States air quality

    NASA Astrophysics Data System (ADS)

    Gonzalez-Abraham, R.; Chung, S. H.; Avise, J.; Lamb, B.; Salathé, E. P., Jr.; Nolte, C. G.; Loughlin, D.; Guenther, A.; Wiedinmyer, C.; Duhl, T.; Zhang, Y.; Streets, D. G.

    2015-11-01

    To understand more fully the effects of global changes on ambient concentrations of ozone and particulate matter with aerodynamic diameter smaller than 2.5 μm (PM2.5) in the United States (US), we conducted a comprehensive modeling effort to evaluate explicitly the effects of changes in climate, biogenic emissions, land use and global/regional anthropogenic emissions on ozone and PM2.5 concentrations and composition. Results from the ECHAM5 global climate model driven with the A1B emission scenario from the Intergovernmental Panel on Climate Change (IPCC) were downscaled using the Weather Research and Forecasting (WRF) model to provide regional meteorological fields. We developed air quality simulations using the Community Multiscale Air Quality Model (CMAQ) chemical transport model for two nested domains with 220 and 36 km horizontal grid cell resolution for a semi-hemispheric domain and a continental United States (US) domain, respectively. The semi-hemispheric domain was used to evaluate the impact of projected global emissions changes on US air quality. WRF meteorological fields were used to calculate current (2000s) and future (2050s) biogenic emissions using the Model of Emissions of Gases and Aerosols from Nature (MEGAN). For the semi-hemispheric domain CMAQ simulations, present-day global emissions inventories were used and projected to the 2050s based on the IPCC A1B scenario. Regional anthropogenic emissions were obtained from the US Environmental Protection Agency National Emission Inventory 2002 (EPA NEI2002) and projected to the future using the MARKet ALlocation (MARKAL) energy system model assuming a business as usual scenario that extends current decade emission regulations through 2050. Our results suggest that daily maximum 8 h average ozone (DM8O) concentrations will increase in a range between 2 to 12 parts per billion (ppb) across most of the continental US. The highest increase occurs in the South, Central and Midwest regions of the US due to

  6. Integrated effects of air pollution and climate change on forests: a northern hemisphere perspective.

    PubMed

    Bytnerowicz, Andrzej; Omasa, Kenji; Paoletti, Elena

    2007-06-01

    Many air pollutants and greenhouse gases have common sources, contribute to radiative balance, interact in the atmosphere, and affect ecosystems. The impacts on forest ecosystems have been traditionally treated separately for air pollution and climate change. However, the combined effects may significantly differ from a sum of separate effects. We review the links between air pollution and climate change and their interactive effects on northern hemisphere forests. A simultaneous addressing of the air pollution and climate change effects on forests may result in more effective research, management and monitoring as well as better integration of local, national and global environmental policies.

  7. The Effects of Global Change upon United States Air Quality

    EPA Science Inventory

    To understand more fully the effects of global changes on ambient concentrations of ozone and particulate matter with aerodynamic diameter smaller than 2.5 μm (PM2.5) in the US, we conducted a comprehensive modeling effort to evaluate explicitly the effects of change...

  8. The effect of future outdoor air pollution on human health and the contribution of climate change

    NASA Astrophysics Data System (ADS)

    Silva, R.; West, J. J.; Lamarque, J.; Shindell, D.; Collins, W.; Dalsoren, S. B.; Faluvegi, G. S.; Folberth, G.; Horowitz, L. W.; Nagashima, T.; Naik, V.; Rumbold, S.; Skeie, R.; Sudo, K.; Takemura, T.; Bergmann, D. J.; Cameron-Smith, P. J.; Cionni, I.; Doherty, R. M.; Eyring, V.; Josse, B.; MacKenzie, I. A.; Plummer, D.; Righi, M.; Stevenson, D. S.; Strode, S. A.; Szopa, S.; Zeng, G.

    2013-12-01

    At present, exposure to outdoor air pollution from ozone and fine particulate matter (PM2.5) causes over 2 million deaths per year, due to respiratory and cardiovascular diseases and lung cancer. Future ambient concentrations of ozone and PM2.5 will be affected by both air pollutant emissions and climate change. Here we estimate the potential impact of future outdoor air pollution on premature human mortality, and isolate the contribution of future climate change due to its effect on air quality. We use modeled present-day (2000) and future global ozone and PM2.5 concentrations from simulations with an ensemble of chemistry-climate models from the Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP). Future air pollution was modeled for global greenhouse gas and air pollutant emissions in the four IPCC AR5 Representative Concentration Pathway (RCP) scenarios, for 2030, 2050 and 2100. All model outputs are regridded to a common 0.5°x0.5° horizontal resolution. Future premature mortality is estimated for each RCP scenario and year based on changes in concentrations of ozone and PM2.5 relative to 2000. Using a health impact function, changes in concentrations for each RCP scenario are combined with future population and cause-specific baseline mortality rates as projected by a single independent scenario in which the global incidence of cardiopulmonary diseases is expected to increase. The effect of climate change is isolated by considering the difference between air pollutant concentrations from simulations with 2000 emissions and a future year climate and simulations with 2000 emissions and climate. Uncertainties in the results reflect the uncertainty in the concentration-response function and that associated with variability among models. Few previous studies have quantified the effects of future climate change on global human health via changes in air quality, and this is the first such study to use an ensemble of global models.

  9. Climate change and air pollution: Effects on pollen allergy and other allergic respiratory diseases.

    PubMed

    D'Amato, Gennaro; Bergmann, Karl Christian; Cecchi, Lorenzo; Annesi-Maesano, Isabella; Sanduzzi, Alessandro; Liccardi, Gennaro; Vitale, Carolina; Stanziola, Anna; D'Amato, Maria

    The observational evidence indicates that recent regional changes in climate, particularly temperature increases, have already affected a diverse set of physical and biological systems in many parts of the world. Allergens patterns are also changing in response to climate change and air pollution can modify the allergenic potential of pollen grains especially in the presence of specific weather conditions. Although genetic factors are important in the development of asthma and allergic diseases, their rising trend can be explained only by changes occurring in the environment and urban air pollution by motor vehicles has been indicated as one of the major risk factors responsible for this increase. Despite some differences in the air pollution profile and decreasing trends of some key air pollutants, air quality is an important concern for public health in the cities throughout the world. Due to climate change, air pollution patterns are changing in several urbanized areas of the world with a significant effect on respiratory health. The underlying mechanisms of all these interactions are not well known yet. The consequences on health vary from decreases in lung function to allergic diseases, new onset of diseases, and exacerbation of chronic respiratory diseases. In addition, it is important to recall that an individual's response to pollution exposure depends on the source and components of air pollution, as well as meteorological conditions. Indeed, some air pollution-related incidents with asthma aggravation do not depend only on the increased production of air pollution, but rather on atmospheric factors that favor the accumulation of air pollutants at ground level. Associations between thunderstorms and asthma morbidity of pollinosis-affected people have also been identified in multiple locations around the world (Fig.1). Cite this as D'Amato G, Bergmann KC, Cecchi L, Annesi-Maesano I, Sanduzzi A, Liccardi G, Vitale C, Stanziola A, D'Amato M. Climate change

  10. [Air quality and climate change].

    PubMed

    Loft, Steffen

    2009-10-26

    Air quality, health and climate change are closely connected. Ozone depends on temperature and the greenhouse gas methane from cattle and biomass. Pollen presence depends on temperature and CO2. The effect of climate change on particulate air pollution is complex, but the likely net effect is greater health risks. Reduction of greenhouse-gas emissions by reduced livestock production and use of combustion for energy production, transport and heating will also improve air quality. Energy savings in buildings and use of CO2 neutral fuels should not deteriorate indoor and outdoor air quality.

  11. A new procedure to analyze the effect of air changes in building energy consumption

    PubMed Central

    2014-01-01

    Background Today, the International Energy Agency is working under good practice guides that integrate appropriate and cost effective technologies. In this paper a new procedure to define building energy consumption in accordance with the ISO 13790 standard was performed and tested based on real data from a Spanish region. Results Results showed that the effect of air changes on building energy consumption can be defined using the Weibull peak function model. Furthermore, the effect of climate change on building energy consumption under several different air changes was nearly nil during the summer season. Conclusions The procedure obtained could be the much sought-after solution to the problem stated by researchers in the past and future research works relating to this new methodology could help us define the optimal improvement in real buildings to reduce energy consumption, and its related carbon dioxide emissions, at minimal economical cost. PMID:24456655

  12. Potential impact of climate change on air pollution-related human health effects.

    PubMed

    Tagaris, Efthimios; Liao, Kuo-Jen; Delucia, Anthony J; Deck, Leland; Amar, Praveen; Russell, Armistead G

    2009-07-01

    The potential health impact of ambient ozone and PM2.5 concentrations modulated by climate change over the United States is investigated using combined atmospheric and health modeling. Regional air quality modeling for 2001 and 2050 was conducted using CMAQ Modeling System with meteorology from the GISS Global Climate Model, downscaled regionally using MM5,keeping boundary conditions of air pollutants, emission sources, population, activity levels, and pollution controls constant. BenMap was employed to estimate the air pollution health outcomes at the county, state, and national level for 2050 caused by the effect of meteorology on future ozone and PM2.5 concentrations. The changes in calculated annual mean PM2.5 concentrations show a relatively modest change with positive and negative responses (increasing PM2.5 levels across the northeastern U.S.) although average ozone levels slightly decrease across the northern sections of the U.S., and increase across the southern tier. Results suggest that climate change driven air quality-related health effects will be adversely affected in more then 2/3 of the continental U.S. Changes in health effects induced by PM2.5 dominate compared to those caused by ozone. PM2.5-induced premature mortality is about 15 times higher then that due to ozone. Nationally the analysis suggests approximately 4000 additional annual premature deaths due to climate change impacts on PM2.5 vs 300 due to climate change-induced ozone changes. However, the impacts vary spatially. Increased premature mortality due to elevated ozone concentrations will be offset by lower mortality from reductions in PM2.5 in 11 states. Uncertainties related to different emissions projections used to simulate future climate, and the uncertainties forecasting the meteorology, are large although there are potentially important unaddressed uncertainties (e.g., downscaling, speciation, interaction, exposure, and concentration-response function of the human health studies).

  13. Effects on asthma and respiratory allergy of Climate change and air pollution.

    PubMed

    D'Amato, Gennaro; Vitale, Carolina; De Martino, Annamaria; Viegi, Giovanni; Lanza, Maurizia; Molino, Antonio; Sanduzzi, Alessandro; Vatrella, Alessandro; Annesi-Maesano, Isabella; D'Amato, Maria

    2015-01-01

    The major changes to our world are those involving the atmosphere and the climate, including global warming induced by anthropogenic factors, with impact on the biosphere and human environment. Studies on the effects of climate changes on respiratory allergy are still lacking and current knowledge is provided by epidemiological and experimental studies on the relationship between allergic respiratory diseases, asthma and environmental factors, like meteorological variables, airborne allergens and air pollution. Epidemiologic studies have demonstrated that urbanization, high levels of vehicle emissions and westernized lifestyle are correlated with an increased frequency of respiratory allergy, mainly in people who live in urban areas in comparison with people living in rural areas. However, it is not easy to evaluate the impact of climate changes and air pollution on the prevalence of asthma in general and on the timing of asthma exacerbations, although the global rise in asthma prevalence and severity could be also considered an effect of air pollution and climate changes. Since airborne allergens and air pollutants are frequently increased contemporaneously in the atmosphere, enhanced IgE-mediated response to aeroallergens and enhanced airway inflammation could account for the increasing frequency of respiratory allergy and asthma in atopic subjects in the last five decades. Pollen allergy is frequently used to study the interrelationship between air pollution and respiratory allergic diseases such as rhinitis and bronchial asthma. Climatic factors (temperature, wind speed, humidity, thunderstorms, etc) can affect both components (biological and chemical) of this interaction. Scientific societies should be involved in advocacy activities, such as those realized by the Global Alliance against chronic Respiratory Diseases (GARD).

  14. Incinerator performance: effects of changes in waste input and furnace operation on air emissions and residues.

    PubMed

    Astrup, Thomas; Riber, Christian; Pedersen, Anne Juul

    2011-10-01

    Waste incineration can be considered a robust technology for energy recovery from mixed waste. Modern incinerators are generally able to maintain relatively stable performance, but changes in waste input and furnace operation may affect emissions. This study investigated how inorganic air emissions and residue composition at a full-scale incinerator were affected by known additions of specific waste materials to the normal municipal solid waste (MSW) input. Six individual experiments were carried out (% ww of total waste input): NaCl (0.5%), shoes (1.6%), automobile shredder waste (14%), batteries (0.5%), poly(vinyl chloride) (5.5%) and chromate-cupper-arsenate impregnated wood (11%). Materials were selected based on chemical composition and potential for being included or excluded from the waste mix. Critical elements in the waste materials were identified based on comparison with six experiments including 'as-large-as-possible' changes in furnace operation (oxygen levels, air supply and burnout level) only using normal MSW as input. The experiments showed that effects from the added waste materials were significant in relation to: air emissions (in particular As, Cd, Cr, Hg, Sb), element transfer coefficients, and residue composition (As, Cd, Cl, Cr, Cu, Hg, Mo, Ni, Pb, S, Sb, Zn). Changes in furnace operation could not be directly linked to changes in emissions and residues. The results outlined important elements in waste which should be addressed in relation to waste incinerator performance. Likely ranges of element transfer coefficients were provided as the basis for sensitivity analysis of life-cycle assessment (LCA) results involving waste incinerator technologies.

  15. EFFECTS OF CHANGING COALS ON THE EMISSIONS OF METAL HAZARDOUS AIR POLLUTANTS FROM THE COMBUSTION OF PULVERIZED COAL

    EPA Science Inventory

    The report discusses tests conducted at EPA's Air Pollution Prevention and Control Division to evaluate the effects of changing coals on emissions of metal hazardous air pollutants from coal-fired boilers. Six coals were burned in a 29 kW (100,000 Btu/hr) down-fired combustor und...

  16. The potential impacts of climate variability and change on air pollution-related health effects in the United States.

    PubMed Central

    Bernard, S M; Samet, J M; Grambsch, A; Ebi, K L; Romieu, I

    2001-01-01

    Climate change may affect exposures to air pollutants by affecting weather, anthropogenic emissions, and biogenic emissions and by changing the distribution and types of airborne allergens. Local temperature, precipitation, clouds, atmospheric water vapor, wind speed, and wind direction influence atmospheric chemical processes, and interactions occur between local and global-scale environments. If the climate becomes warmer and more variable, air quality is likely to be affected. However, the specific types of change (i.e., local, regional, or global), the direction of change in a particular location (i.e., positive or negative), and the magnitude of change in air quality that may be attributable to climate change are a matter of speculation, based on extrapolating present understanding to future scenarios. There is already extensive evidence on the health effects of air pollution. Ground-level ozone can exacerbate chronic respiratory diseases and cause short-term reductions in lung function. Exposure to particulate matter can aggravate chronic respiratory and cardiovascular diseases, alter host defenses, damage lung tissue, lead to premature death, and possibly contribute to cancer. Health effects of exposures to carbon monoxide, sulfur dioxide, and nitrogen dioxide can include reduced work capacity, aggravation of existing cardiovascular diseases, effects on pulmonary function, respiratory illnesses, lung irritation, and alterations in the lung's defense systems. Adaptations to climate change should include ensuring responsiveness of air quality protection programs to changing pollution levels. Research needs include basic atmospheric science work on the association between weather and air pollutants; improving air pollution models and their linkage with climate change scenarios; and closing gaps in the understanding of exposure patterns and health effects. PMID:11359687

  17. The potential impacts of climate variability and change on air pollution-related health effects in the United States.

    PubMed

    Bernard, S M; Samet, J M; Grambsch, A; Ebi, K L; Romieu, I

    2001-05-01

    Climate change may affect exposures to air pollutants by affecting weather, anthropogenic emissions, and biogenic emissions and by changing the distribution and types of airborne allergens. Local temperature, precipitation, clouds, atmospheric water vapor, wind speed, and wind direction influence atmospheric chemical processes, and interactions occur between local and global-scale environments. If the climate becomes warmer and more variable, air quality is likely to be affected. However, the specific types of change (i.e., local, regional, or global), the direction of change in a particular location (i.e., positive or negative), and the magnitude of change in air quality that may be attributable to climate change are a matter of speculation, based on extrapolating present understanding to future scenarios. There is already extensive evidence on the health effects of air pollution. Ground-level ozone can exacerbate chronic respiratory diseases and cause short-term reductions in lung function. Exposure to particulate matter can aggravate chronic respiratory and cardiovascular diseases, alter host defenses, damage lung tissue, lead to premature death, and possibly contribute to cancer. Health effects of exposures to carbon monoxide, sulfur dioxide, and nitrogen dioxide can include reduced work capacity, aggravation of existing cardiovascular diseases, effects on pulmonary function, respiratory illnesses, lung irritation, and alterations in the lung's defense systems. Adaptations to climate change should include ensuring responsiveness of air quality protection programs to changing pollution levels. Research needs include basic atmospheric science work on the association between weather and air pollutants; improving air pollution models and their linkage with climate change scenarios; and closing gaps in the understanding of exposure patterns and health effects.

  18. Simulating and Analyzing Long-Term Changes in Emissions, Air Quality, Aerosol Feedback Effects and Human Health

    EPA Science Inventory

    This presentation covers work performed by the authors to characterize changes in emissions over the 1990 – 2010 time period, quantify the effects of these emission changes on air quality and aerosol/radiation feedbacks using both observations and model simulations, and fin...

  19. THE EFFECT OF OPENING WINDOWS ON AIR CHANGE RATES IN TWO HOMES

    EPA Science Inventory

    Over 300 air change rate experiments were completed in two occupied residences: a two-story detached house in Redwood City, CA and a three-story townhouse in Reston, VA. A continuous monitor was used to measure the decay of sulfur hexafluoride tracer gas over periods of 1 to 1...

  20. [Effects of sudden air temperature and pressure changes on mortality in the Czech Republic].

    PubMed

    Plavcová, E; Kyselý, J

    2009-04-01

    We have developed an algorithm for identifying sudden changes in air pressure and temperature over the Czech Republic. Such events were retrieved from the data covering in 1986-2005 and were matched with the daily numbers of all-cause deaths and deaths due to cardiovascular diseases from the national database, separately for the whole population and that aged 70 years and over. Excess daily mortality was determined by calculating deviations of the observed number of deaths from the expected number of deaths for each day in the respective groups. The relative deviation of the mortality the mean was calculated as the ratio of the excess mortality to the expected number of deaths. We used 3-hour air pressure data from 10 meteorological stations and hourly air temperature data from 9 stations representative of the Czech Republic. Pressure changes were evaluated on time scales of 3, 6 and 12 hours, separately for summer and winter time. Temperature changes were evaluated on a 24-hour time scale, separately for summer and winter season. Events characterized by pressure or temperature changes above the critical threshold and recorded within 24 hours at more than 50% of meteorological stations were retrieved. The critical thresholds were defined separately for each station using quantiles of distributions of air pressure and temperature changes. Relative mortality deviations for days D-2 (2 days before the change) to D+7 (7 days after the change) were averaged over the retrieved events. Statistical significance of the mean relative deviation was tested using the Monte Carlo method. Increased mortality followed large temperature increases and large pressure drops both in summer and winter months. Decreased mortality was observed after large pressure increases and large temperature drops in summer. Mortality variations are usually more pronounced in the population aged 70 years and over, and cardiovascular diseases account for most deaths after sudden temperature changes.

  1. Air Pollution and Climate Change Effects on Allergies in the Anthropocene: Abundance, Interaction, and Modification of Allergens and Adjuvants.

    PubMed

    Reinmuth-Selzle, Kathrin; Kampf, Christopher J; Lucas, Kurt; Lang-Yona, Naama; Fröhlich-Nowoisky, Janine; Shiraiwa, Manabu; Lakey, Pascale S J; Lai, Senchao; Liu, Fobang; Kunert, Anna T; Ziegler, Kira; Shen, Fangxia; Sgarbanti, Rossella; Weber, Bettina; Bellinghausen, Iris; Saloga, Joachim; Weller, Michael G; Duschl, Albert; Schuppan, Detlef; Pöschl, Ulrich

    2017-04-06

    Air pollution and climate change are potential drivers for the increasing burden of allergic diseases. The molecular mechanisms by which air pollutants and climate parameters may influence allergic diseases, however, are complex and elusive. This article provides an overview of physical, chemical and biological interactions between air pollution, climate change, allergens, adjuvants and the immune system, addressing how these interactions may promote the development of allergies. We reviewed and synthesized key findings from atmospheric, climate, and biomedical research. The current state of knowledge, open questions, and future research perspectives are outlined and discussed. The Anthropocene, as the present era of globally pervasive anthropogenic influence on planet Earth and, thus, on the human environment, is characterized by a strong increase of carbon dioxide, ozone, nitrogen oxides, and combustion- or traffic-related particulate matter in the atmosphere. These environmental factors can enhance the abundance and induce chemical modifications of allergens, increase oxidative stress in the human body, and skew the immune system toward allergic reactions. In particular, air pollutants can act as adjuvants and alter the immunogenicity of allergenic proteins, while climate change affects the atmospheric abundance and human exposure to bioaerosols and aeroallergens. To fully understand and effectively mitigate the adverse effects of air pollution and climate change on allergic diseases, several challenges remain to be resolved. Among these are the identification and quantification of immunochemical reaction pathways involving allergens and adjuvants under relevant environmental and physiological conditions.

  2. What health professionals should know about the health effects of air pollution and climate change on children and pregnant mothers

    PubMed Central

    Poursafa, Parinaz; Kelishadi, Roya

    2011-01-01

    BACKGROUND: Health professionals face the adverse health effects of climate change and air pollution in their practices. This review underscores the effects of these environmental factors on maternal and children's health, as the most vulnerable groups to climate change and air pollution. METHODS: We reviewed electronic databases for a search of the literature to find relevant studies published in English from 1990 to 2011. RESULTS: Environmental factors, notably climate change and air pollution influence children's health before conception and continue during pregnancy, childhood, and adolescence. Experts have suggested that such health hazards may represent the greatest public health challenge that humanity has faced. The accumulation of greenhouse gases such as carbon dioxide, primarily from burning fossil fuels, results in warming which has an impact on air pollution particularly on levels of ozone and particulates. Heat-related health effects include increased rates of pregnancy complications, pre-eclampsia, eclampsia, low birth weight, renal effects, vector-borne diseases as malaria and dengue, increased diarrheal and respiratory disease, food insecurity, decreased quality of foods (notably grains), malnutrition, water scarcity, exposures to toxic chemicals, worsened poverty, natural disasters and population displacement. Air pollution has many adverse health effects for mothers and children. In addition to short-term effects like premature labour, intrauterine growth retardation, neonatal and infant mortality rate, malignancies (notably leukaemia and Hodgkin lymphoma), respiratory diseases, allergic disorders and anaemia, exposure to criteria air pollutants from early life might be associated with increase in stress oxidative, inflammation and endothelial dysfunction which in turn might have long-term effects on chronic non-communicable diseases. CONCLUSIONS: Health professionals have an exclusive capability to help prevent and reduce the harmful effects of

  3. Florida State University Receives EPA Funding to Improve Understanding of the Effects of Climate Change on Indoor Air Quality

    EPA Pesticide Factsheets

    ATLANTA - The U.S. Environmental Protection Agency (EPA) today announced that Florida State University in Tallahassee, Fla. has received a $500,000 grant to improve understanding of the effects of climate change on indoor air quality. The grant is a

  4. The Effect of Conceptual Change Approach to Eliminate 9th Grade High School Students' Misconceptions about Air Pressure

    ERIC Educational Resources Information Center

    Akbas, Yavuz; Gencturk, Ebru

    2011-01-01

    The aim of this study was to determine the effectiveness of teaching based on conceptual change overcome misconceptions of 9th grade high school students about the subject of air pressure. The sampling of the study was formed with two classes of 9th grade students from a general high school in the city-center of Trabzon. A quasi-experimental…

  5. Air pressure effects on sea level changes during the twentieth century

    NASA Astrophysics Data System (ADS)

    Piecuch, Christopher G.; Thompson, Philip R.; Donohue, Kathleen A.

    2016-10-01

    Interpretation of tide gauge data in terms sea level (η) and ocean dynamics requires estimates of air pressure (pa) to determine the ocean's isostatic response—the inverted barometer effect (ηib). Three gridded pa products (HadSLP2, NOAA-20CRv2, and ERA-20C) are used alongside meteorological station pa and tide gauge η records to evaluate the contribution of ηib to η changes over the twentieth century. Agreement between gridded products is better during more recent periods and over regions with good historical data coverage, whereas it is worse for earlier time periods or in ocean areas with poor observational data coverage. Comparison against station data reveals the presence of systematic errors in the gridded products, for example, such that uncertainties estimated through differencing the gridded products underestimate the true errors by roughly 40% on interannual and decadal time scales. Notwithstanding such correlated errors, gridded products are still useful for interpretation of tide gauge data. Removing gridded estimates of ηib from η records reduces spatial variance in centennial trends across tide gauges by 10-30%, formal errors in centennial trends from individual gauges by ˜5%, and the temporal variance in detrended records by 10-15% on average (depending on choice of gridded product). Results here advocate for making the ηib correction to tide gauge records in studies of ocean circulation and global η over long, multidecadal, and centennial time scales using an ensemble mean taken across several gridded ηib products.

  6. Transportation, Air Pollution, and Climate Change

    MedlinePlus

    ... Share Facebook Twitter Google+ Pinterest Contact Us Transportation, Air Pollution, and Climate Change Accomplishments & Successes View successes from ... reduce carbon pollution. Carbon pollution from transportation Other Air Pollution Learn about smog, soot, ozone, and other air ...

  7. Strategic effects of future environmental policy commitments: climate change, solar radiation management and correlated air pollutants.

    PubMed

    Qu, Jingwen; Silva, Emilson Caputo Delfino

    2015-03-15

    We study the effects of environmental policy commitments in a futuristic world in which solar radiation management (SRM) can be utilized to reduce climate change damages. Carbon and sulfur dioxide emissions (correlated pollutants) can be reduced through tradable permits. We show that if nations simultaneously commit to carbon permit policies, national SRM levels rise with carbon quotas. Alternatively, if they simultaneously commit to SRM policies, the global temperature falls with each unit increase in the global SRM level. A nation always wishes to be a leader in policymaking, but prefers carbon to SRM policymaking. The globe prefers SRM policy commitments.

  8. Health Effects of Air Pollution

    MedlinePlus

    ... Health effects of air pollution Health effects of air pollution Breathing air that is not clean can hurt ... important to know about the health effects that air pollution can have on you and others. Once you ...

  9. The Impact of Future Emissions Changes on Air Pollution Concentrations and Related Human Health Effects

    NASA Astrophysics Data System (ADS)

    Mikolajczyk, U.; Suppan, P.; Williams, M.

    2015-12-01

    Quantification of potential health benefits of reductions in air pollution on the local scale is becoming increasingly important. The aim of this study is to conduct health impact assessment (HIA) by utilizing regionally and spatially specific data in order to assess the influence of future emission scenarios on human health. In the first stage of this investigation, a modeling study was carried out using the Weather Research and Forecasting (WRF) model coupled with Chemistry to estimate ambient concentrations of air pollutants for the baseline year 2009, and for the future emission scenarios in southern Germany. Anthropogenic emissions for the baseline year 2009 are derived from the emission inventory provided by the Netherlands Organization of Applied Scientific Research (TNO) (Denier van der Gon et al., 2010). For Germany, the TNO emissions were replaced by gridded emission data with a high spatial resolution of 1/64 x 1/64 degrees. Future air quality simulations are carried out under different emission scenarios, which reflect possible energy and climate measures in year 2030. The model set-up included a nesting approach, where three domains with horizontal resolution of 18 km, 6 km and 2 km were defined. The simulation results for the baseline year 2009 are used to quantify present-day health burdens. Concentration-response functions (CRFs) for PM2.5 and NO2 from the WHO Health risks of air Pollution in Europe (HRAPIE) project were applied to population-weighted mean concentrations to estimate relative risks and hence to determine numbers of attributable deaths and associated life-years lost. In the next step, future health impacts of projected concentrations were calculated taking into account different emissions scenarios. The health benefits that we assume with air pollution reductions can be used to provide options for future policy decisions to protect public health.

  10. Deformation induced topographic effects in inversion of temporal gravity changes: First look at Free Air and Bouguer terms

    NASA Astrophysics Data System (ADS)

    Vajda, Peter; Zahorec Pavol, Pavol; Papčo, Juraj; Kubová, Anna

    2015-06-01

    We review here the gravitational effects on the temporal (time-lapse) gravity changes induced by the surface deformation (vertical displacements). We focus on two terms, one induced by the displacement of the benchmark (gravity station) in the ambient gravity field, and the other imposed by the attraction of the masses within the topographic deformation rind. The first term, coined often the Free Air Effect (FAE), is the product of the vertical gradient of gravity (VGG) and the vertical displacement of the benchmark. We examine the use of the vertical gradient of normal gravity, typically called the theoretical or normal Free Air Gradient (normal FAG), as a replacement for the true VGG in the FAE, as well as the contribution of the topography to the VGG. We compute a topographic correction to the normal FAG, to offer a better approximation of the VGG, and evaluate its size and shape (spatial behavior) for a volcanic study area selected as the Central Volcanic Complex (CVC) on Tenerife, where this correction reaches 77% of the normal FAG and varies rapidly with terrain. The second term, imposed by the attraction of the vertically displaced topo-masses, referred to here as the Topographic Deformation Effect (TDE) must be computed by numerical evaluation of the Newton volumetric integral. As the effect wanes off quickly with distance, a high resolution DEM is required for its evaluation. In practice this effect is often approximated by the planar or spherical Bouguer deformation effect (BDE). By a synthetic simulation at the CVC of Tenerife we show the difference between the rigorously evaluated TDE and its approximation by the planar BDE. The complete effect, coined here the Deformation Induced Topographic Effect (DITE) is the sum of FAE and TDE. Next we compare by means of synthetic simulations the DITE with two approximations of DITE typically used in practice: one amounting only to the first term in which the VGG is approximated by normal FAG, the other adopting a

  11. [Air pollution, climate change and health].

    PubMed

    Ballester, Ferran

    2005-01-01

    Emissions into the atmosphere related to the climate change may further worsen the effects which air pollution has on the health of our citizens, not only indirectly due to the impact of weather phenomenon, but directly, due to the direct effects pollutants have on health. However, the efforts throughout most of the world have been aimed at dealing with these two problems separately for too many years. In fact, it is very often believed that the climate's health-safeguarding benefits would be achieved in the long term. To the contrary, what has become obvious over recent years is that the actions for reducing the emissions of polluting gases could redound in beneficial effects in the short term due to the reduction of the impact of air pollutants on the health of our citizens. This article presents the possible risks of the pollutants most closely related to climate changes, such as ozone and fine particles. Bearing in mind the uncertainties and unknowns related to this subject, the main implications for the policies related to this matter in Spain, as well as the needs for research are set out herein. In this regard, both from the standpoint of monitoring as well as research, it is considered necessary for an epidemiological monitoring system of the effects of air pollution and the relationship thereof to global changes to be established.

  12. Tree-Ring Nitrogen Isotopes As Environmental Monitoring Tools - Inferring Air Quality Changes And Climate Effects

    NASA Astrophysics Data System (ADS)

    Savard, M. M.; Begin, C.; Smirnoff, A.; Marion, J.

    2008-12-01

    Anthropogenic emissions of atmospheric nitrogen greatly increased over the last 150 years, however the monitoring of nitrous oxide concentration in North America started only recently, generally during the last 30 years. Could the geochemical characteristics of tree rings be used to infer past changes in nitrogen cycles of temperate regions? To address this question we use long-term series (125 years) of nitrogen stable isotopes (δ15N) obtained from rings of pine (Pinus strobus) and beech (Fagus grandifolia) trees in the Montreal region (western Quebec), and of beech specimens in the Georgian Bay Islands National Park (central Ontario). Reliability tests of N concentrations in wood treated for removal of soluble materials reveal that the reproducibility from tree to tree is poor, and that the concentrations in both Pine and Beech trees change in the heartwood-sapwood transition zones. We therefore reject N concentration as environmental indicator. Alternatively, the N stable isotopes pass all reliability tests. In Montreal, short-term δ15N fluctuations correlate directly with precipitation and inversely with temperature. A long-term decreasing isotope trend suggests progressive changes in soil chemistry after 1951. A pedochemical change is also inferred for the Georgian Bay site on the basis of a positive δ15N trend initiated after 1971. At both sites, the long-term δ15N series correlate with a proxy for NOx emissions, and the δ13C values of the same ring series suggest that all studied trees have been stressed by phytotoxic pollutants. We propose that the contrasted long-term δ15N changes of Montreal and Georgian Bay reflect deposition of NOx emissions from cars and coal-power plants, with higher proportions from coal burning in Georgian Bay. This interpretation is conceivable because recent monitoring indicates that coal-power plant NOx emissions play an important role in the annual N budget in Ontario, but they seem negligible on the Quebec side. This

  13. The effect of processing and compositional changes on the tribology of PM212 in air

    NASA Technical Reports Server (NTRS)

    Bogdanski, Michael S.; Sliney, Harold E.; Dellacorte, Christopher

    1993-01-01

    The effects of processing and compositional variations on the tribological performance of PM212 were studied. PM212 is a self lubricating powder metallurgy composite, comprised of a wear resistant metal bonded chromium carbide matrix, containing the solid lubricants barium fluoride/calcium fluoride eutectic and silver. Several composites were formulated which had lubricant, matrix, and processing variations. Processing variations included sintering and hot isostatic pressing. Pins fabricated from the composites were slid against superalloys disks in a pin-on-disk tribometer to study the tribological properties. Several composites exhibited low friction and wear in sliding against a nickel based superalloy. The tribological performance by several different composites showed that the composition of PM212 can be altered without dramatically affecting performance.

  14. Continuous measurements of air change rates in an occupied house for 1 year: the effect of temperature, wind, fans, and windows.

    PubMed

    Wallace, L A; Emmerich, S J; Howard-Reed, C

    2002-07-01

    A year-long investigation of air change rates in an occupied house was undertaken to establish the effects of temperature, wind velocity, use of exhaust fans, and window-opening behavior. Air change rates were calculated by periodically injecting a tracer gas (SF(6)) into the return air duct and measuring the concentration in 10 indoor locations sequentially every minute by a gas chromatograph equipped with an electron capture detector. Temperatures were also measured outdoors and in the 10 indoor locations. Relative humidity (RH) was measured outdoors and in five indoor locations every 5 min. Wind speed and direction in the horizontal plane were measured using a portable meteorological station mounted on the rooftop. Use of the thermostat-controlled attic fan was recorded automatically. Indoor temperatures increased from 21 degrees C in winter to 27 degrees C in summer. Indoor RH increased from 20% to 70% in the same time period. Windows were open only a few percent of the time in winter but more than half the time in summer. About 4600 hour-long average air change rates were calculated from the measured tracer gas decay rates. The mean (SD) rate was 0.65 (0.56) h(-1). Tracer gas decay rates in different rooms were very similar, ranging only from 0.62 to 0.67 h(-1), suggesting that conditions were well mixed throughout the year. The strongest influence on air change rates was opening windows, which could increase the rate to as much as 2 h(-1) for extended periods, and up to 3 h(-1) for short periods of a few hours. The use of the attic fan also increased air change rates by amounts up to 1 h(-1). Use of the furnace fan had no effect on air change rates. Although a clear effect of indoor-outdoor temperature difference could be discerned, its magnitude was relatively small, with a very large temperature difference of 30 degrees C (54 degrees F) accounting for an increase in the air change rate of about 0.6 h(-1). Wind speed and direction were found to have very

  15. [Effects of air temperature increase and precipitation change on grain yield and quality of spring wheat in semiarid area of Northwest China].

    PubMed

    Wang, He-ling; Zhang, Qiang; Wang, Run-yuan; Gan, Yan-tai; Niu, Jun-yi; Zhang, Kai; Zhao, Fu-nian; Zhao, Hong

    2015-01-01

    In order to predict effects of climate changing on growth, quality and grain yields of spring wheat, a field experiment was conducted to investigate the effects of air temperature increases (0 °C, 1.0 °C, 2.0° C and 3.0°) and precipitation variations (decrease 20%, unchanging and increase 20%) on grain yields, quality, diseases and insect pests of spring wheat at the Dingxi Arid Meteorology and Ecological Environment Experimental Station of the Institute of Arid Meteorology of China Meteorological Administration (35°35' N ,104°37' E). The results showed that effects of precipitation variations on kernel numbers of spring wheat were not significant when temperature increased by less than 2.0° C , but was significant when temperature increased by 3.0° C. Temperature increase enhanced kernel numbers, while temperature decrease reduced kernel numbers. The negative effect of temperature on thousand-kernel mass of spring wheat increased with increasing air temperature. The sterile spikelet of spring wheat response to air temperature was quadratic under all precipitation regimes. Compared with control ( no temperature increase), the decreases of grain yield of spring wheat when air temperature increased by 1.0°C, 2.0°C and 3.0°C under each of the three precipitation conditions (decrease 20%, no changing and increase 20%) were 12.1%, 24.7% and 42.7%, 8.4%, 15.1% and 21.8%, and 9.0%, 15.5% and 22.2%, respectively. The starch content of spring wheat decreased and the protein content increased with increasing air temperature. The number of aphids increased when air temperature increased by 2.0°C , but decreased when air temperature increased by 3.0°CT. The infection rates of rust disease increased with increasing air temperature.

  16. Changing the Air Force Narrative

    DTIC Science & Technology

    2014-10-14

    tablets and televisions as well (Lessin and Ante, 2013). Similarly, few things capture the imagination of today’s youth like video games, and few adults...has had to take with recent scandals. A simple Google News search of the term “Air Force” reveals mainly articles about sexual assault, suicide ...The Bully -pulpit: Theodore Roosevelt, William Howard Taft, and the Golden Age of Journalism. New York: Simon and Schuster. Greenert, J. and Welsh, M

  17. Simulations and projections of major air pollutants over the United States and uncertainty analyses, effects of natural change and human activities

    NASA Astrophysics Data System (ADS)

    Lei, Hang

    Changes in global climate and pollutant emissions are very likely to continue in the coming decades driven by the human-related activities and natural fluctuations in the Earth climate system. These potential changes would have very important consequences on regional air quality over the contiguous United States due to their effects on atmospheric chemical and physical processes. To understand these effects, the present studies use the global climate chemistry model, CAM-Chem version 3, to systematically assess potential changes in major air pollutants including surface ozone, particulate matter and mercury from the present (1998--2002) to the 2050 (2048--2052). The projections of future air quality consider changes in global climate, precursor emissions from anthropogenic and biogenic sources, and pollutant transport. Moreover, to evaluate the projection uncertainties resulting from different plausible trends of climate and emissions as a result of unknown human-related activities and climate variations, three IPCC SRES scenarios, A1FI, A1B and B1, are considered and compared to evaluate the resulting uncertainty in projecting future pollutant concentrations. To achieve a better understanding on the effect of mineral dust emissions on changes in future air quality especially the PM concentrations, a physical dust aerosol module is developed and incorporated into the CAM-Chem model. A mercury module is developed for the CAM-Chem model to simulate the atmospheric cycle of mercury and its consequences on the toxicity of U.S. air quality. For the study of ozone air quality, we focus on the risk of high ozone episodes and the relative contributions from changes in local anthropogenic emissions (LE) versus changes in intercontinental transport (ICT) on 2050 U.S. surface ozone air quality. It is found that the projected changes in air temperature, precipitation, lighting, planetary boundary layer height and cyclone activities tend to intensify the associated extreme

  18. Exploring the consequences of climate change for indoor air quality

    NASA Astrophysics Data System (ADS)

    Nazaroff, William W.

    2013-03-01

    Climate change will affect the concentrations of air pollutants in buildings. The resulting shifts in human exposure may influence public health. Changes can be anticipated because of altered outdoor pollution and also owing to changes in buildings effected in response to changing climate. Three classes of factors govern indoor pollutant levels in occupied spaces: (a) properties of pollutants; (b) building factors, such as the ventilation rate; and (c) occupant behavior. Diversity of indoor conditions influences the public health significance of climate change. Potentially vulnerable subpopulations include not only the young and the infirm but also those who lack resources to respond effectively to changing conditions. Indoor air pollutant levels reflect the sum of contributions from indoor sources and from outdoor pollutants that enter with ventilation air. Pollutant classes with important indoor sources include the byproducts of combustion, radon, and volatile and semivolatile organic compounds. Outdoor pollutants of special concern include particulate matter and ozone. To ensure good indoor air quality it is important first to avoid high indoor emission rates for all pollutants and second to ensure adequate ventilation. A third factor is the use of air filtration or air cleaning to achieve further improvements where warranted. Reprinted with permission from Climate Change, the Indoor Environment, and Health (2011) by the National Academy of Sciences, Courtesy of the National Academies Press, Washington, DC.

  19. Air Pollution, Greenhouse Gases and Climate Change

    NASA Astrophysics Data System (ADS)

    Ramanathan, V.

    2007-12-01

    The global build up of greenhouse gases (GHGs), is the most significant environmental issue facing the planet. GHGs warm the surface and the atmosphere with significant implications for, rainfall, retreat of glaciers and sea ice, sea level, among other factors. What is less recognized, however, is a comparably major global problem dealing with air pollution. Until about ten years ago, air pollution was thought to be just an urban or a local problem. But new data have revealed that, due to fast long range transport, air pollution is transported across continents and ocean basins, resulting in trans-oceanic and trans-continental plumes of atmospheric brown clouds (ABCs) containing sub micron size particles, i.e, aerosols. ABCs intercept sunlight by absorbing as well as reflecting it, both of which lead to a large surface dimming. The dimming effect is enhanced further because aerosols nucleate more cloud drops which makes the clouds reflect more solar radiation. While the solar heating at the surface is reduced by aerosols in ABCs, the atmospheric solar heating increases due to soot solar absorption. The net difference between the dimming and the atmospheric solar heating is estimated be negative which contributes to a global cooling effect. The global cooling from this negative ABC forcing may have masked as much as 50% of the warming due to GHGs. We will identify regional and mega-city hot spots of ABCs. Long range transport from these hot spots gives rise to wide spread plumes over the adjacent oceans. Such a pattern of regionally concentrated surface dimming and atmospheric solar heating, accompanied by wide spread dimming over the oceans, gives rise to large regional effects. Only during the last decade, we have begun to comprehend the surprisingly large regional impacts. The large north-south gradient in the ABC dimming has altered the north-south gradients in sea surface temperatures, which in turn has been shown by models to decrease rainfall over the

  20. Omega-3 Fatty Acid Supplementation Appears to Attenuate Particulate Air Pollution-induced Cardiac Effects and Lipid Changes in Healthy Middle-aged Adults.

    EPA Science Inventory

    Context: Air pollution exposure has been associated with adverse cardiovascular effects. A recent epidemiologic study reported that omega-3 fatty acid (fish oil) supplementation blunted the cardiac responses to air pollution exposure. Objective: To evaluate in a randomized contro...

  1. Changing the Paradigm of Air Pollution Monitoring

    EPA Science Inventory

    Historically, approaches for monitoring air pollution generally use expensive, complex, stationary equipment,1,2 which limits who collects data, why data are collected, and how data are accessed. This paradigm is changing with the materialization of lower-cost, easy-to...

  2. [Temporal change in annual air temperature and heat island effect in a coastal city and an inland city at mid-latitude in China during 1956-1998].

    PubMed

    Chao, Lu-men; Sun, Jian-xin

    2009-12-01

    Temporal changes in air temperature and urban heat island (UHI) effects during 1956-1998 were compared between a coastal city, Ji' nan, and an inland city, Xi' an, which were similar in latitude, size and development. During 1956-1978, except that the annual mean minimum temperature in Ji' nan increased by 0.37 degrees C x 10 a(-1), the temperature variables in the two cities did not display any apparent trend. During 1979-1998, all temperature variables of the two cities showed an increasing trend. Comparing with that in Ji' nan, the increasing rate of annual mean maximum temperature and annual mean temperature in Xi' an was greater, but that of annual mean minimum temperature was smaller. In the two cities, heat island effect occurred during 1956-1978 but without any apparent trend, whereas during 1979-1998, this effect increased with time, especially in Xi' an where the annual mean minimum temperature and annual mean temperature increased by 0.22 degrees C x 10 a(-1) and 0.32 degrees C x 10 a(-1), respectively. Both the level and the inter-annual variation of the heat island effect were much greater in Ji' nan than in Xi' an, but the increasing rate of this effect was greater in Xi' an than in Ji' nan. Obvious differences were observed in the increasing rate of annual mean maximum air temperature, annual mean air temperature, and annual mean minimum temperature as well as the heat island effect in Ji' nan, whereas negligible differences were found in Xi' an. Among the three temperature variables, annual mean minimum temperature displayed the most obvious increasing trend and was most affected by heat island effect, while annual mean maximum temperature was most variable inter-annually. Geographical location not only affected the magnitude of urban warming, but also affected the mode of urban warming and the strength of heat island effect.

  3. Dose- and time- effect responses of DNA methylation and histone H3K9 acetylation changes induced by traffic-related air pollution

    PubMed Central

    Ding, Rui; Jin, Yongtang; Liu, Xinneng; Ye, Huaizhuang; Zhu, Ziyi; Zhang, Yuan; Wang, Ting; Xu, Yinchun

    2017-01-01

    As an important risk factor of respiratory disorders, traffic-related air pollution (TRAP) has caused extensive concerns. Epigenetic change has been considered a link between TRAP and respiratory diseases. However, the exact effects of TRAP on epigenetic changes are still unclear. Here we investigated the dose- and time- effect responses of TRAP on DNA methylations and H3K9 acetylation (H3K9ac) in both blood and lung tissues of rats. The findings showed that every 1 μg/m3 increase of TRAP components were associated with changes in %5 mC (95% CI) in LINE-1, iNOS, p16CDKN2A, and APC ranging from −0.088% (−0.150, −0.026) to 0.102 (0.049, 0.154), as well as 0.276 (0.053, 0.498) to 0.475 (0.103, 0.848) ng/mg increase of H3K9ac. In addition, every 1 more day exposure at high level of TRAP (in tunnel) also significantly changed the levels of DNA methylation (ranging from −0.842% to 0.248%) and H3K9ac (16.033 and 15.718 ng/mg pro in PBMC and lung tissue, respectively) changes. Season and/or sex could interact with air pollutants in affecting DNA methylation and H3K9ac. The findings showed that TRAP exposure is dose- and time- dependently associated with the changes of DNA methylation and H3K9ac. PMID:28256616

  4. How emissions, climate, and land use change will impact mid-century air quality over the United States: a focus on effects at national parks

    NASA Astrophysics Data System (ADS)

    Martin, M. Val; Heald, C. L.; Lamarque, J.-F.; Tilmes, S.; Emmons, L. K.; Schichtel, B. A.

    2015-03-01

    We use a global coupled chemistry-climate-land model (CESM) to assess the integrated effect of climate, emissions and land use changes on annual surface O3 and PM2.5 in the United States with a focus on national parks (NPs) and wilderness areas, using the RCP4.5 and RCP8.5 projections. We show that, when stringent domestic emission controls are applied, air quality is predicted to improve across the US, except surface O3 over the western and central US under RCP8.5 conditions, where rising background ozone counteracts domestic emission reductions. Under the RCP4.5 scenario, surface O3 is substantially reduced (about 5 ppb), with daily maximum 8 h averages below the primary US Environmental Protection Agency (EPA) National Ambient Air Quality Standards (NAAQS) of 75 ppb (and even 65 ppb) in all the NPs. PM2.5 is significantly reduced in both scenarios (4 μg m-3; ~50%), with levels below the annual US EPA NAAQS of 12 μg m-3 across all the NPs; visibility is also improved (10-15 dv; >75 km in visibility range), although some western US parks with Class I status (40-74 % of total sites in the US) are still above the 2050 planned target level to reach the goal of natural visibility conditions by 2064. We estimate that climate-driven increases in fire activity may dominate summertime PM2.5 over the western US, potentially offsetting the large PM2.5 reductions from domestic emission controls, and keeping visibility at present-day levels in many parks. Our study indicates that anthropogenic emission patterns will be important for air quality in 2050. However, climate and land use changes alone may lead to a substantial increase in surface O3 (2-3 ppb) with important consequences for O3 air quality and ecosystem degradation at the US NPs. Our study illustrates the need to consider the effects of changes in climate, vegetation, and fires in future air quality management and planning and emission policy making.

  5. Air quality research: perspective from climate change modelling research.

    PubMed

    Semazzi, Fredrick

    2003-06-01

    A major component of climate change is a manifestation of changes in air quality. This paper explores the question of air quality from the climate change modelling perspective. It reviews recent research advances on the cause-effect relationships between atmospheric air composition and climate change, primarily based on the Intergovernmental Panel on Climate Change (IPCC) assessment of climate change over the past decade. There is a growing degree of confidence that the warming world over the past century was caused by human-related changes in the composition of air. Reliability of projections of future climate change is highly dependent on future emission scenarios that have been identified that in turn depend on a multitude of complicated interacting social-economic factors. Anticipated improvements in the performance of climate models is a major source of optimism for better climate projections in the future, but the real benefits of its contribution will be closely coupled with other sources of uncertainty, and in particular emission projections.

  6. Human health effects of air pollution.

    PubMed Central

    Folinsbee, L J

    1993-01-01

    Over the past three or four decades, there have been important advances in the understanding of the actions, exposure-response characteristics, and mechanisms of action of many common air pollutants. A multidisciplinary approach using epidemiology, animal toxicology, and controlled human exposure studies has contributed to the database. This review will emphasize studies of humans but will also draw on findings from the other disciplines. Air pollutants have been shown to cause responses ranging from reversible changes in respiratory symptoms and lung function, changes in airway reactivity and inflammation, structural remodeling of pulmonary airways, and impairment of pulmonary host defenses, to increased respiratory morbidity and mortality. Quantitative and qualitative understanding of the effects of a small group of air pollutants has advanced considerably, but the understanding is by no means complete, and the breadth of effects of all air pollutants is only partially understood. PMID:8354181

  7. Modeling green infrastructure land use changes on future air ...

    EPA Pesticide Factsheets

    Green infrastructure can be a cost-effective approach for reducing stormwater runoff and improving water quality as a result, but it could also bring co-benefits for air quality: less impervious surfaces and more vegetation can decrease the urban heat island effect, and also result in more removal of air pollutants via dry deposition with increased vegetative surfaces. Cooler surface temperatures can also decrease ozone formation through the increases of NOx titration; however, cooler surface temperatures also lower the height of the boundary layer resulting in more concentrated pollutants within the same volume of air, especially for primary emitted pollutants (e.g. NOx, CO, primary particulate matter). To better understand how green infrastructure impacts air quality, the interactions between all of these processes must be considered collectively. In this study, we use a comprehensive coupled meteorology-air quality model (WRF-CMAQ) to simulate the influence of planned land use changes that include green infrastructure in Kansas City (KC) on regional meteorology and air quality. Current and future land use data was provided by the Mid-America Regional Council for 2012 and 2040 (projected land use due to population growth, city planning and green infrastructure implementation). These land use datasets were incorporated into the WRF-CMAQ modeling system allowing the modeling system to propagate the changes in vegetation and impervious surface coverage on meteoro

  8. Effects of air pollution on changes in lung function induced by exercise in children with chronic respiratory symptoms

    PubMed Central

    Timonen, K; Pekkanen, J; Tiittanen, P; Salonen, R

    2002-01-01

    Objective: To investigate how daily variations in ambient air pollution, especially in particles, during the cold of winter affect repeated measurements of baseline lung function and exercise induced bronchial responsiveness among primary school children with chronic respiratory symptoms. Methods: During alternate school weeks (mamimum five) from February to April 1994, 33 children took part in exercise challenge tests (n=141 tests). The exercise challenges were conducted outdoors in a school yard in the centre of Kuopio, Finland. Spirometric lung functions were measured indoors before the exercise, and 3 and 10 minutes after. Daily mean concentrations of PM10, black smoke (BS), NO2, CO, SO2, and particle size and numbers were monitored at a nearby fixed monitoring site. Results: Daily variations in ambient air pollution were not associated with enhanced bronchial responsiveness. However, increased concentrations of BS, PM10, particle numbers, NO2, and CO were consistently associated with an impairment of baseline lung functions. The reductions in forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) were 0.5% and 0.6%, respectively, for each 10 µg/m3 increase in BS (lag 2). Conclusion: Particles derived from combustion affect baseline lung function rather than bronchial responsiveness among children with chronic respiratory symptoms. PMID:11850557

  9. Air flow paths and porosity/permeability change in a saturated zone during in situ air sparging.

    PubMed

    Tsai, Yih-Jin

    2007-04-02

    This study develops methods to estimate the change in soil characteristics and associated air flow paths in a saturated zone during in situ air sparging. These objectives were achieved by performing combined in situ air sparging and tracer testing, and comparing the breakthrough curves obtained from the tracer gas with those obtained by a numerical simulation model that incorporates a predicted change in porosity that is proportional to the air saturation. The results reveal that revising the porosity and permeability according to the distribution of gas saturation is helpful in breakthrough curve fitting, however, these changes are unable to account for the effects of preferential air flow paths, especially in the zone closest to the points of air injection. It is not known the extent to which these preferential air flow paths were already present versus created, increased, or reduced as a result of the air sparging experiment. The transport of particles from around the sparging well could account for the overall increase in porosity and permeability observed in the study. Collection of soil particles in a monitoring well within 2m of the sparging well provided further evidence of the transport of particles. Transport of particles from near the sparging well also appeared to decrease the radius of influence (ROI). Methods for predicting the effects of pressurized air injection and water flow on the creation or modification of preferential air flow paths are still needed to provide a full description of the change in soil conditions that accompany air sparging.

  10. Composition changes in refrigerant blends for automotive air conditioning

    SciTech Connect

    Jetter, J.J.; Delafield, F.R.; Ng, A.S.; Ratanaphruks, K.; Tufts, M.W.

    1999-07-01

    Three refrigerant blends used to replace the chlorofluorocarbon R-12 in automotive air conditioners were evaluated for composition changes due to typical servicing and leakage. When recommended service procedures were followed, changes in blend compositions were relatively small. Small changes in blend compositions caused no significant changes in refrigeration capacities. However, when recommended procedures were not followed, changes in compositions were relatively large. The amount of change in composition and the resulting effect on performance varied among the three refrigerant blends that were tested. Of the three blends, a quaternary blend containing hydrochlorofluorocarbon R-22 had the greatest changes in composition, while a binary blend containing hydrofluorocarbon R-134a had the smallest changes in composition.

  11. The effectiveness of air bags.

    PubMed

    Barry, S; Ginpil, S; O'Neill, T J

    1999-11-01

    Previous research has shown that the installation of air bags in vehicles significantly reduces crash related deaths, but these analyses have used statistical techniques which have not been capable of controlling for other major determinants of crash survival. This study analysed data from the US FARS database of fatal crashes using conditional logistic regression which is simultaneously able to estimate occupant protection effects for a range of variables. Results of the analysis provided a comparative quantification of both the effect of the air bag as well as other well known determinants of occupant crash survival (age, seat belt use, and gender). When potentially confounding variables were controlled, both the driver and passenger side air bag devices were shown to significantly reduce the probability of death in direct frontal collisions, but the effect size calculated was small compared to the effect of the seat belt. The effect size may also be very small in absolute terms depending on the severity of the crash involved. Given the limited benefit of the air bag, efforts to promote air bags seem particularly difficult to justify in countries such as the United States where the vastly superior occupant protection of the seat belt is under-utilised.

  12. Effect of regional precursor emission controls on long-range ozone transport - Part 2: Steady-state changes in ozone air quality and impacts on human mortality

    NASA Astrophysics Data System (ADS)

    West, J. J.; Naik, V.; Horowitz, L. W.; Fiore, A. M.

    2009-08-01

    Large-scale changes in ozone precursor emissions affect ozone directly in the short term, and also affect methane, which in turn causes long-term changes in ozone that affect surface ozone air quality. Here we assess the effects of changes in ozone precursor emissions on the long-term change in surface ozone via methane, as a function of the emission region, by modeling 10% reductions in anthropogenic nitrogen oxide (NOx) emissions from each of nine world regions. Reductions in NOx emissions from all world regions increase methane and long-term surface ozone. While this long-term increase is small compared to the intra-regional short-term ozone decrease, it is comparable to or larger than the short-term inter-continental ozone decrease for some source-receptor pairs. The increase in methane and long-term surface ozone per ton of NOx reduced is greatest in tropical and Southern Hemisphere regions, exceeding that from temperate Northern Hemisphere regions by roughly a factor of ten. We also assess changes in premature ozone-related human mortality associated with regional precursor reductions and long-range transport, showing that for 10% regional NOx reductions, the strongest inter-regional influence is for emissions from Europe affecting mortalities in Africa. Reductions of NOx in North America, Europe, the Former Soviet Union, and Australia are shown to reduce more mortalities outside of the source regions than within. Among world regions, NOx reductions in India cause the greatest number of avoided mortalities per ton, mainly in India itself. Finally, by increasing global methane, NOx reductions in one hemisphere tend to cause long-term increases in ozone concentration and mortalities in the opposite hemisphere. Reducing emissions of methane, and to a lesser extent carbon monoxide and non-methane volatile organic compounds, alongside NOx reductions would avoid this disbenefit.

  13. Effect of regional precursor emission controls on long-range ozone transport - Part 2: steady-state changes in ozone air quality and impacts on human mortality

    NASA Astrophysics Data System (ADS)

    West, J. J.; Naik, V.; Horowitz, L. W.; Fiore, A. M.

    2009-03-01

    Large-scale changes in ozone precursor emissions affect ozone directly in the short term, and also affect methane, which in turn causes long-term changes in ozone that affect surface ozone air quality. Here we assess the effects of changes in ozone precursor emissions on the long-term change in surface ozone via methane, as a function of the emission region, by modeling 10% reductions in anthropogenic nitrogen oxide (NOx) emissions from each of nine world regions. Reductions in NOx emissions from all world regions increase methane and long-term surface ozone. While this long-term increase is small compared to the intra-regional short-term ozone decrease, it is comparable to or larger than the short-term inter-continental ozone decrease for some source-receptor pairs. The increase in methane and long-term surface ozone per ton of NOx reduced is greatest in tropical and Southern Hemisphere regions, exceeding that from temperate Northern Hemisphere regions by roughly a factor of ten. We also assess changes in premature ozone-related human mortality associated with regional precursor reductions and long-range transport, showing that for 10% regional NOx reductions, the strongest inter-regional influence is for emissions from Europe affecting mortalities in Africa. Reductions of NOx in North America, Europe, the Former Soviet Union, and Australia are shown to reduce more mortalities outside of the source regions than within. Among world regions, NOx reductions in India cause the greatest number of avoided mortalities per ton, mainly in India itself. Finally, by increasing global methane, NOx reductions in one hemisphere tend to cause long-term increases in ozone concentration and mortalities in the opposite hemisphere. Reducing emissions of methane, and to a lesser extent carbon monoxide and non-methane volatile organic compounds, alongside NOx reductions would avoid this disbenefit.

  14. Evaluation of the impact of transportation changes on air quality

    NASA Astrophysics Data System (ADS)

    Titos, G.; Lyamani, H.; Drinovec, L.; Olmo, F. J.; Močnik, G.; Alados-Arboledas, L.

    2015-08-01

    Transport regulation at local level for the abatement of air pollution has gained significant traction in the EU. In this work, we analyze the effect of different transportation changes on air quality in two similarly sized cities: Granada (Spain) and Ljubljana (Slovenia). Several air pollutants were measured at both sites before and after the implementation of the changes. In Ljubljana, a 72% reduction of local black carbon (BC), from 5.6 to 1.6 μg/m3, was observed after the restriction was implemented. In Granada, statistically significant reductions of 1.3 μg/m3 (37%) in BC and of 15 μg/m3 (33%) in PM10 concentrations were observed after the public transportation re-organization. However, the improvement observed in air quality was very local since other areas of the cities did not improve significantly. We show that closing streets to private traffic, renewal of the bus fleet and re-organization of the public transportation significantly benefit air quality.

  15. Mobile Air Monitoring: Measuring Change in Air Quality in the City of Hamilton, 2005-2010

    ERIC Educational Resources Information Center

    Adams, Matthew D.; DeLuca, Patrick F.; Corr, Denis; Kanaroglou, Pavlos S.

    2012-01-01

    This paper examines the change in air pollutant concentrations between 2005 and 2010 occurring in the City of Hamilton, Ontario, Canada. After analysis of stationary air pollutant concentration data, we analyze mobile air pollutant concentration data. Air pollutants included in the analysis are CO, PM[subscript 2.5], SO[subscript 2], NO,…

  16. Evaluating the effectiveness of air quality interventions.

    PubMed

    van Erp, Annemoon M M; O'Keefe, Robert; Cohen, Aaron J; Warren, Jane

    2008-01-01

    Evaluating the extent to which air quality regulations improve public health--sometimes referred to as accountability--is part of an emerging effort to assess the effectiveness of environmental regulatory policies. Air quality has improved substantially in the United States and Western Europe in recent decades, with far less visible pollution and decreasing concentrations of several major pollutants. In large part, these gains were achieved through increasingly stringent air quality regulations. The costs associated with compliance and, importantly, the need to ensure that the regulations are achieving the intended public health benefits underscore the importance of accountability research. To date, accountability research has emphasized measuring the effects of actions already taken to improve air quality. Such research may also contribute to estimating the burden of disease that might be avoided in the future if certain actions are taken. The Health Effects Institute (HEI) currently funds eight ongoing studies on accountability, which cover near-term interventions to improve air quality including (1) a ban on the sale of coal, (2) replacing old wood stoves with cleaner ones, (3) decreasing sulfur content in fuel, (4) measures to reduce traffic, and (5) longer term, wide-ranging actions or events (such as complex changes associated with the reunification of Germany). HEI is also funding the development of methods and research to assess regulations that are implemented incrementally over extended periods of time, such as Title IV of the 1990 Clean Air Act Amendments, which reduces sulfur dioxide emissions from power plants in the eastern United States.

  17. The Operational Air National Guard: Relationship Changes and Policy Implications

    DTIC Science & Technology

    2015-02-13

    spending, thirteen years of war, ambitious domestic programs and monetary policies aimed at overcoming the 2008 economic collapse led to the Budget...AIR WAR COLLEGE AIR UNIVERSITY THE "OPERATIONAL" AIR NATIONAL GUARD: RELATIONSHIP CHANGES AND POLICY IMPLICATIONS by Todd L Remington...2015 to 00-00-2015 4. TITLE AND SUBTITLE The Operational Air National Guard: Relationship Changes And Policy Implications 5a. CONTRACT NUMBER 5b

  18. Health Effects of Air Pollution.

    ERIC Educational Resources Information Center

    Environmental Education Report and Newsletter, 1985

    1985-01-01

    Summarizes health hazards associated with air pollution, highlighting the difficulty in establishing acceptable thresholds of exposure. Respiratory disease, asthma, cancer, cardiovascular disease, and other problems are addressed. Indicates that a wide range of effects from any one chemical exists and that there are differences in sensitivity to…

  19. Increases in ambient particulate matter air pollution, acute changes in platelet function, and effect modification by aspirin and omega-3 fatty acids: A panel study.

    PubMed

    Becerra, Adan Z; Georas, Steve; Brenna, J Thomas; Hopke, Philip K; Kane, Cathleen; Chalupa, David; Frampton, Mark W; Block, Robert; Rich, David Q

    2016-01-01

    Increased particulate matter (PM) air pollutant concentrations have been associated with platelet activation. It was postulated that elevated air pollutant concentrations would be associated with increases in measures of platelet function and that responses would be blunted when taking aspirin and/or fish oil. Data from a sequential therapy trial (30 subjects with type 2 diabetes mellitus), with 4 clinic visits (first: no supplements, second: aspirin, third: omega-3 fatty acid supplements, fourth: aspirin and omega-3 fatty acids) per subject, were utilized. Using linear mixed models, adjusted for relative humidity, temperature, visit number, and season, changes in three platelet function measures including (1) aggregation induced by adenosine diphosphate (ADP), (2) aggregation induced by collagen, and (3) thromboxane B2 production were associated with interquartile range (IQR) increases in mean concentrations of ambient PM2.5, black carbon, ultrafine particles (UFP; 10-100 nm), and accumulation mode particles (AMP; 100-500 nm) in the previous 1-96 h. IQR increases in mean UFP and AMP concentrations were associated with significant decreases in platelet response, with the largest being a -0.43 log(pg/ml) decrease in log(thromboxane B2) (95% CI = -0.8, -0.1) associated with each 582-particles/cm(3) increase in AMP, and a -1.7 ohm reduction in collagen-induced aggregation (95% CI = -3.1, -0.3) associated with each 2097-particles/cm(3) increase in UFP in the previous 72 h. This UFP effect on thromboxane B2 was significantly muted in diabetic subjects taking aspirin (-0.01 log[pg/ml]; 95% CI = -0.4, 0.3). The reason for this finding remains unknown, and needs to be investigated in future studies.

  20. COMPOSITION CHANGES IN REFRIGERANT BLENDS FOR AUTOMOTIVE AIR CONDITIONING

    EPA Science Inventory

    Three refrigerant blends used to replace CFC-12 in automotive air conditioners were evaluated for composition changes due to typical servicing and leakage. When recommended service procedures were followed, changes in blend compositions were relatively small. Small changes in b...

  1. Ground cloud air quality effects

    NASA Technical Reports Server (NTRS)

    Brubaker, K. L.

    1980-01-01

    The effects of the ground cloud associated with launching of a large rocket on air quality are discussed. The ground cloud consists of the exhaust emitted by the rocket during the first 15 to 25 seconds following ignition and liftoff, together with a large quantity of entrained air, cooling water, dust and other debris. Immediately after formation, the ground cloud rises in the air due to the buoyant effect of its high thermal energy content. Eventually, at an altitude typically between 0.7 and 3 km, the cloud stabilizes and is carried along by the prevailing wind at that altitude. For the use of heavy lift launch vehicles small quantities of nitrogen oxides, primarily nitric oxide and nitrogen dioxide, are expected to be produced from a molecular nitrogen impurity in the fuel or liquid oxygen, or from entrainment and heating of ambient air in the hot rocket exhaust. In addition, possible impurities such as sulfur in the fuel would give rise to a corresponding amount of oxidation products such as sulfur dioxide.

  2. ASSESSMENT OF THE IMPACTS OF GLOBAL CHANGE ON REGIONAL U.S. AIR QUALITY: A SYNTHESIS OF CLIMATE CHANGE IMPACTS ON GROUND-LEVEL OZONE (AN INTERIM REPORT OF THE U.S. EPA GLOBAL CHANGE RESEARCH PROGRAM)

    EPA Science Inventory

    The Air Quality Assessment Final Report is intended for managers and scientists working on air quality to provide them with information on the potential effects of climate change on regional air quality in the United States.

  3. Model-based estimation of changes in air temperature seasonality

    NASA Astrophysics Data System (ADS)

    Barbosa, Susana; Trigo, Ricardo

    2010-05-01

    Seasonality is a ubiquitous feature in climate time series. Climate change is expected to involve not only changes in the mean of climate parameters but also changes in the characteristics of the corresponding seasonal cycle. Therefore the identification and quantification of changes in seasonality is a highly relevant topic in climate analysis, particularly in a global warming context. However, the analysis of seasonality is far from a trivial task. A key challenge is the discrimination between long-term changes in the mean and long-term changes in the seasonal pattern itself, which requires the use of appropriate statistical approaches in order to be able to distinguish between overall trends in the mean and trends in the seasons. Model based approaches are particularly suitable for the analysis of seasonality, enabling to assess uncertainties in the amplitude and phase of seasonal patterns within a well defined statistical framework. This work addresses the changes in the seasonality of air temperature over the 20th century. The analysed data are global air temperature values close to surface (2m above ground) and mid-troposphere (500 hPa geopotential height) from the recently developed 20th century reanalysis. This new 3-D Reanalysis dataset is available since 1891, considerably extending all other Reanalyses currently in use (e.g. NCAR, ECWMF), and was obtained with the Ensemble Filter (Compo et al., 2006) by assimilation of pressure observations into a state-of-the-art atmospheric general circulation model that includes the radiative effects of historical time-varying CO2 concentrations, volcanic aerosol emissions and solar output variations. A modeling approach based on autoregression (Barbosa et al, 2008; Barbosa, 2009) is applied within a Bayesian framework for the estimation of a time varying seasonal pattern and further quantification of changes in the amplitude and phase of air temperature over the 20th century. Barbosa, SM, Silva, ME, Fernandes, MJ

  4. IMPACTS OF AIR POLLUTION AND CLIMATE CHANGE ON FOREST ECOSYSTEMS - EMERGING RESEARCH NEEDS

    EPA Science Inventory

    Outcomes from the 22nd meeting for Specialists in Air Pollution Effects on Forest Ecosystems "Forests under Anthropogenic Pressure - Effects of Air Pollution, Climate Change and Urban Development", September 10-16, 2006, Riverside, CA, USA are summarized. Tropospheric ozone is st...

  5. The effectiveness of a heated air curtain

    NASA Astrophysics Data System (ADS)

    Frank, Daria

    2014-11-01

    Air curtains are high-velocity plane turbulent jets which are installed in the doorway in order to reduce the heat and the mass exchange between two environments. The air curtain effectiveness E is defined as the fraction of the exchange flow prevented by the air curtain compared to the open-door situation. In the present study, we investigate the effects of an opposing buoyancy force on the air curtain effectiveness. Such an opposing buoyancy force arises for example if a downwards blowing air curtain is heated. We conducted small-scale experiments using water as the working fluid with density differences created by salt and sugar. The effectiveness of a downwards blowing air curtain was measured for situations in which the initial density of the air curtain was less than both the indoor and the outdoor fluid density, which corresponds to the case of a heated air curtain. We compare the effectiveness of the heated air curtain to the case of the neutrally buoyant air curtain. It is found that the effectiveness starts to decrease if the air curtain is heated beyond a critical temperature. Furthermore, we propose a theoretical model to describe the dynamics of the buoyant air curtain. Numerical results obtained from solving this model corroborate our experimental findings.

  6. Impact of Climate Change on Air Quality and Public Health in Urban Areas.

    PubMed

    Hassan, Noor Artika; Hashim, Zailina; Hashim, Jamal Hisham

    2016-03-01

    This review discusses how climate undergo changes and the effect of climate change on air quality as well as public health. It also covers the inter relationship between climate and air quality. The air quality discussed here are in relation to the 5 criteria pollutants; ozone (O3), carbon dioxide (CO2), nitrogen dioxide (NO2), sulfur dioxide (SO2), and particulate matter (PM). Urban air pollution is the main concern due to higher anthropogenic activities in urban areas. The implications on health are also discussed. Mitigating measures are presented with the final conclusion.

  7. EPA Research Funding Aims to Improve Understanding of Climate Change Impacts on Indoor Air Quality

    EPA Pesticide Factsheets

    Harvard College is one of only nine institutions that will share nearly $8 million from the US Environmental Protection Agency to study how climate change affects indoor air quality and the resulting health effects.

  8. Characterizing climate change impacts on human exposures to air pollutants

    EPA Science Inventory

    Human exposures to air pollutants such as ozone (O3) have the potential to be altered by changes in climate through multiple factors that drive population exposures, including: ambient pollutant concentrations, human activity patterns, population sizes and distributions, and hous...

  9. Modeling air temperature changes in Northern Asia

    NASA Astrophysics Data System (ADS)

    Onuchin, A.; Korets, M.; Shvidenko, A.; Burenina, T.; Musokhranova, A.

    2014-11-01

    Based on time series (1950-2005) of monthly temperatures from 73 weather stations in Northern Asia (limited by 70-180° EL and 48-75° NL), it is shown that there are statistically significant spatial differences in character and intensity of the monthly and yearly temperature trends. These differences are defined by geomorphological and geographical parameters of the area including exposure of the territory to Arctic and Pacific air mass, geographic coordinates, elevation, and distances to Arctic and Pacific oceans. Study area has been divided into six domains with unique groupings of the temperature trends based on cluster analysis. An original methodology for mapping of temperature trends has been developed and applied to the region. The assessment of spatial patterns of temperature trends at the regional level requires consideration of specific regional features in the complex of factors operating in the atmosphere-hydrosphere-lithosphere-biosphere system.

  10. Motor Vehicles, Air Pollution, and Climate Change

    NASA Astrophysics Data System (ADS)

    Mark, Jason

    2000-04-01

    Despite years of technical progress, motor vehicles continue to be a leading cause of environmental damage in the United States. For example, today's cars and trucks are the largest source of air pollution in many urban areas. US motor vehicles also account for 25 percent of the nation's carbon emissions, more than most countries emit from all sources combined. Fortunately, a host of technical improvements are emerging that could go a long ways towards taking vehicles out of the pollution picture. In the near-term, improving on the century-old internal combustion engine can deliver much-needed incremental gains. But electric drive vehicles--whether powered by batteries, small engines in hybrid configuration, or fuel cells--ultimately offer the greatest promise. Such technologies could dramatically reduce energy use, greenhouse gas emissions, and key air pollutants. The bulk of technical attention in recent years has been focused on improving the passenger vehicle, which will be the dominant energy consumer in the transportation sector for years to come. But freight trucks are also of growing concern, both because their contribution to global warming is on the rise and because serious questions are being raised about the public health impact of diesel technology. As a result, heavy trucks are emerging as a priority issue. Capitalizing on the opportunity presented by new technologies will not only require continued technical innovation but also policy action. As research into improved engines, fuels, and drive systems bears fruit over the coming years, aggressive and prudent policies will ensure that these new options make it onto the road and deliver on their environmental promise.

  11. Committee on air pollution effects research: 40 years of UK air pollution.

    PubMed

    Fowler, David; Dise, Nancy; Sheppard, Lucy

    2016-01-01

    The UK Committee on Air Pollution Effects Research (CAPER) was established 40 years ago. This special section was compiled to mark this anniversary. During this time there have been dramatic changes in the composition of the air over the UK. The four papers in this special section of Environmental Pollution represent the current air pollution effects research focus on ozone and nitrogen deposition, two related issues and are proving from a policy perspective to be quite intractable issues. The UK CAPER research community continues to advance the underpinning science and engages closely with the user community in government departments.

  12. Climate Change and Agriculture: Effects and Adaptation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This document is a synthesis of science literature on the effects of climate change on agriculture and issues associated with agricultural adaptation to climate change. Information is presented on how long-term changes in air temperatures, precipitation, and atmospheric levels of carbon dioxide wi...

  13. Ambient air pollution, climate change, and population health in China.

    PubMed

    Kan, Haidong; Chen, Renjie; Tong, Shilu

    2012-07-01

    As the largest developing country, China has been changing rapidly over the last three decades and its economic expansion is largely driven by the use of fossil fuels, which leads to a dramatic increase in emissions of both ambient air pollutants and greenhouse gases (GHGs). China is now facing the worst air pollution problem in the world, and is also the largest emitter of carbon dioxide. A number of epidemiological studies on air pollution and population health have been conducted in China, using time-series, case-crossover, cross-sectional, cohort, panel or intervention designs. The increased health risks observed among Chinese population are somewhat lower in magnitude, per amount of pollution, than the risks found in developed countries. However, the importance of these increased health risks is greater than that in North America or Europe, because the levels of air pollution in China are very high in general and Chinese population accounts for more than one fourth of the world's totals. Meanwhile, evidence is mounting that climate change has already affected human health directly and indirectly in China, including mortality from extreme weather events; changes in air and water quality; and changes in the ecology of infectious diseases. If China acts to reduce the combustion of fossil fuels and the resultant air pollution, it will reap not only the health benefits associated with improvement of air quality but also the reduced GHG emissions. Consideration of the health impact of air pollution and climate change can help the Chinese government move forward towards sustainable development with appropriate urgency.

  14. Air-Pollution-Mediated Changes in Alpine Ecosystems and Ecotones.

    PubMed

    Rusek, Josef

    1993-08-01

    Soil biological parameters (e.g., Collembola), soil types, soil chemical parameters (pH, humus substances), and plant communities were studied in different ecosystems and ecotones in alpine, subalpine, and spruce forest zones in the Tatra National Park, Slovak Republic. The preliminary, selected data, based on a long-term research program, showed a high sensitivity of some alpine ecotones and ecosystems to long-distance transported acid deposits. The changes in different ecosystem parameters since 1977 were more extensive in alpine grasslands on limestone than on granite. The greatest soil pH decrease was in the plant communities Festucetum versicoloris (-1.5 pH), Geranio-Alchemilletum crinitae (-1.32 pH), and Saxifragetum perdurantis (-1.25 pH), which are restricted to places with snow accumulation and water runoff gullies. In these ecosystems the greatest changes occurred in the leaching of humus substances. Some formerly less abundant and rare soil animals restricted to acid bedrock became dominant in some ecosystems on limestone as well as on granite; other formerly dominant species disappeared from the entire study area (e.g., Folsomia alpina). The aerial extent of some ecosystems changed substantially since 1977, and their surrounding ecotones moved into the space formerly occupied by one of the adjacent ecosystems. These changes are detectable by remote-sensing methods. In Central European mountains, strongly affected by global and regional industrial air pollution (e.g., Krusne Hory, Krkonose, Beskydy), spruce forests started to die back from higher to lower mountain elevations. The effects of air pollution on alpine and subalpine vegetation were not studied there. Strong alterations in alpine ecosystems and ecotones were detected by the author during long-term studies in the High Tatra Mountains, and I suggest that subalpine and mountain forest belts will be affected here in the near future as they were in the more polluted Central European mountains. The

  15. Co-benefits of air quality and climate change policies on air quality of the Mediterranean

    NASA Astrophysics Data System (ADS)

    Pozzoli, Luca; Mert Gokturk, Ozan; Unal, Alper; Kindap, Tayfun; Janssens-Maenhout, Greet

    2015-04-01

    The Mediterranean basin is one of the regions of the world where significant impacts due to climate changes are predicted to occur in the future. Observations and model simulations are used to provide to the policy makers scientifically based estimates of the necessity to adjust national emission reductions needed to achieve air quality objectives in the context of a changing climate, which is not only driven by GHGs, but also by short lived climate pollutants, such as tropospheric ozone and aerosols. There is an increasing interest and need to design cost-benefit emission reduction strategies, which could improve both regional air quality and global climate change. In this study we used the WRF-CMAQ air quality modelling system to quantify the contribution of anthropogenic emissions to ozone and particulate matter concentrations in Europe and the Eastern Mediterranean and to understand how this contribution could change in different future scenarios. We have investigated four different future scenarios for year 2050 defined during the European Project CIRCE: a "business as usual" scenario (BAU) where no or just actual measures are taken into account; an "air quality" scenario (BAP) which implements the National Emission Ceiling directive 2001/81/EC member states of the European Union (EU-27); a "climate change" scenario (CC) which implements global climate policies decoupled from air pollution policies; and an "integrated air quality and climate policy" scenario (CAP) which explores the co-benefit of global climate and EU-27 air pollution policies. The BAP scenario largely decreases summer ozone concentrations over almost the entire continent, while the CC and CAP scenarios similarly determine lower decreases in summer ozone but extending all over the Mediterranean, the Middle East countries and Russia. Similar patterns are found for winter PM concentrations; BAP scenario improves pollution levels only in the Western EU countries, and the CAP scenario determines

  16. Effects of rheological change by addition of carboxymethylcellulose in culture media of an air-lift fermentor on poly-D-3-hydroxybutyric acid productivity in autotrophic culture of hydrogen-oxidizing bacterium, Alcaligenes eutrophus.

    PubMed

    Taga, N; Tanaka, K; Ishizaki, A

    1997-03-05

    The effects of rheological change by addition of sodium carboxymethylcellulose (CMC) to culture medium in an air-lift-type fermentor on autotrophic production of poly-(D-3-hydroxybutyric acid) [P(3HB)] by two-stage culture of Alcaligenes eutrophus is investigated. Addition of 0.05% CMC increased P(3HB) production rate during the P(3HB) accumulation phase to twice that of the control culture. It was thought that addition of a small amount of CMC was beneficial for production of P(3HB) employing the air-lift fermentor under safe autotrophic culture conditions in wich oxygen concentration was maintained below 6.9% (v/v). the volumetric mass transfer coefficient (K(L)a) observed in the presence of CMC is shown to correlated with the P(3HB) production rate obtained. (c) 1997 John Wiley & Sons, Inc. Biotechnol Bioeng 53: 529-533, 1997.

  17. Effect of Initial Mixture Temperature on Flame Speed of Methane-Air, Propane-Air, and Ethylene-Air Mixtures

    NASA Technical Reports Server (NTRS)

    Dugger, Gordon L

    1952-01-01

    Flame speeds based on the outer edge of the shadow cast by the laminar Bunsen cone were determined as functions of composition for methane-air mixtures at initial mixture temperatures ranging from -132 degrees to 342 degrees c and for propane-air and ethylene-air mixtures at initial mixture temperatures ranging from -73 degrees to 344 degrees c. The data showed that maximum flame speed increased with temperature at an increasing rate. The percentage change in flame speed with change in initial temperature for the three fuels followed the decreasing order, methane, propane, and ethylene. Empirical equations were determined for maximum flame speed as a function of initial temperature over the temperature range covered for each fuel. The observed effect of temperature on flame speed for each of the fuels was reasonably well predicted by either the thermal theory as presented by Semenov or the square-root law of Tanford and Pease.

  18. European Air Quality and Climate Change: a numerical modeling study

    NASA Astrophysics Data System (ADS)

    Lacressonniere, G.

    2011-12-01

    In the context of climate change, the evolution of air quality in Europe is a challenging scientific question, despite the political measures taken to limit and reduce anthropogenic emissions. Heat waves, changes in transport pathways or synoptic patterns, increase of emissions in other areas in the world, or for instance possible increase of biogenic emissions or changes in deposition and land use may affect adversely future Air Quality levels in Europe. In the context of a project co-funded by the French environment agency ADEME, a numerical modeling study has begun relying on the tools used by Météo-France for its contribution to the 5th IPCC assessment report, to GMES atmospheric services (MACC FP7 project) and to the French national operational Air Quality platform Prév'Air (http://www.prevair.org). In particular, the MOCAGE 3-D chemical transport model (CTM) is used with a configuration comprising a global (2°) and a European domain (0.2°), allowing representation of both long-range transport of pollutants and European Air Quality at relevant resolutions and with a two-ways coupling. MOCAGE includes 47 layers from the surface to 5hPa. The first step of this project was to assess the impact of meteorological forcings, either analyses ("best" meteorology available for the recent past) or climate runs for the current atmosphere, on air quality hindcasts with MOCAGE over Europe. For these climate runs, we rely on Météo-France Earth-System model CNRM-CM, and particularly the ARPEGE-climate general circulation model for the atmosphere. By studying several key variables for Air Quality (surface and low troposphere concentrations of ozone, nitrogen oxides, volatile organic compounds, radicals, PM,...), we investigated the indicators that are robust, through averages over several years, (monthly averages, frequency of exceedances, AOTs, ...) for a given climate when using climatological forcings instead of analyses, which constitutes the reference. Both

  19. Household air pollution and its effects on health.

    PubMed

    Apte, Komalkirti; Salvi, Sundeep

    2016-01-01

    Household air pollution is a leading cause of disability-adjusted life years in Southeast Asia and the third leading cause of disability-adjusted life years globally. There are at least sixty sources of household air pollution, and these vary from country to country. Indoor tobacco smoking, construction material used in building houses, fuel used for cooking, heating and lighting, use of incense and various forms of mosquito repellents, use of pesticides and chemicals used for cleaning at home, and use of artificial fragrances are some of the various sources that contribute to household air pollution. Household air pollution affects all stages of life with multi-systemic health effects, and its effects are evident right from pre-conception to old age. In utero exposure to household air pollutants has been shown to have health effects which resonate over the entire lifetime. Exposures to indoor air pollutants in early childhood also tend to have repercussions throughout life. The respiratory system bears the maximum brunt, but effects on the cardiovascular system, endocrine system, and nervous system are largely underplayed. Household air pollutants have also been implicated in the development of various types of cancers. Identifying household air pollutants and their health implications helps us prepare for various health-related issues. However, the real challenge is adopting changes to reduce the health effects of household air pollution and designing innovative interventions to minimize the risk of further exposure. This review is an attempt to understand the various sources of household air pollution, the effects on health, and strategies to deal with this emergent risk factor of global mortality and morbidity.

  20. Household air pollution and its effects on health

    PubMed Central

    Apte, Komalkirti; Salvi, Sundeep

    2016-01-01

    Household air pollution is a leading cause of disability-adjusted life years in Southeast Asia and the third leading cause of disability-adjusted life years globally. There are at least sixty sources of household air pollution, and these vary from country to country. Indoor tobacco smoking, construction material used in building houses, fuel used for cooking, heating and lighting, use of incense and various forms of mosquito repellents, use of pesticides and chemicals used for cleaning at home, and use of artificial fragrances are some of the various sources that contribute to household air pollution. Household air pollution affects all stages of life with multi-systemic health effects, and its effects are evident right from pre-conception to old age. In utero exposure to household air pollutants has been shown to have health effects which resonate over the entire lifetime. Exposures to indoor air pollutants in early childhood also tend to have repercussions throughout life. The respiratory system bears the maximum brunt, but effects on the cardiovascular system, endocrine system, and nervous system are largely underplayed. Household air pollutants have also been implicated in the development of various types of cancers. Identifying household air pollutants and their health implications helps us prepare for various health-related issues. However, the real challenge is adopting changes to reduce the health effects of household air pollution and designing innovative interventions to minimize the risk of further exposure. This review is an attempt to understand the various sources of household air pollution, the effects on health, and strategies to deal with this emergent risk factor of global mortality and morbidity. PMID:27853506

  1. Three Northwest Institutions Receive Funding from EPA for Research to Better Understand the Effects of Climate Change on Indoor Air Quality

    EPA Pesticide Factsheets

    (Seattle - July 28, 2015) On July 21, the U.S. Environmental Protection Agency announced its continued commitment to improving America's indoor air quality by providing almost $8 million to fund nine institutions, including three in the Northwest, research

  2. Air bubble bursting effect of lotus leaf.

    PubMed

    Wang, Jingming; Zheng, Yongmei; Nie, Fu-Qiang; Zhai, Jin; Jiang, Lei

    2009-12-15

    In this paper, a phenomenon of air bubbles quickly bursting within several milliseconds on a "self-cleaning" lotus leaf was described. This observation prompted the synthesis of artificial surfaces similar to that of the lotus leaf. The artificial leaf surfaces, prepared by photolithography and wet etching, showed a similar air bubble bursting effect. Smooth and rough silicon surfaces with an ordered nanostructure or patterned microstructure were utilized to study the contribution of the micro/nano hierarchical structures to this phenomenon of air bubble bursting. Air bubbles were found to burst on some superhydrophobic surfaces with microstructure (within 220 ms). However, air bubbles burst much more rapidly (within 13 ms) on similar surfaces with micro/nanostructure. The height, width, and spacing of hierarchical structures could also affect air bubble bursting, and the effect of the height was more obvious. When the height of hierarchical structures was around the height found in natural lotus papillae, the width and spacing were significant for air bubble bursting. An original model was proposed to further evaluate the reason why the micro/nano hierarchical rough structures had an excellent air bubble bursting effect, and the validity of the model was theoretically demonstrated.

  3. Pulmonary Health Effects of Air Pollution

    PubMed Central

    Kurt, Ozlem Kar; Zhang, Jingjing; Pinkerton, Kent E.

    2016-01-01

    Purpose of the review Air pollution continues to be a major public health concern affecting nine out of ten individuals living in urban areas worldwide. Exposure to air pollution is the ninth leading risk factor for cardiopulmonary mortality. The aim of this review is to examine the current literature for the most recent updates on health effects of specific air pollutants and their impact on asthma, chronic obstructive pulmonary disease (COPD), lung cancer and respiratory infection. Recent findings A total of 53 publications were reviewed to establish new insights as to how air pollution is associated with pulmonary morbidity and mortality. Considerable past evidence suggests that air pollution is an important factor that enhances pulmonary disease, while also causing greater harm in susceptible populations, such as children, the elderly and those of low socio-economic status worldwide. Asthma, COPD, lung cancer and respiratory infections all seem to be exacerbated due to exposure to a variety of environmental air pollutants with the greatest effects due to particulate matter (PM), ozone and nitrogen oxides. New publications reviewed reaffirm these findings. Summary Continued vigilence will be essential to lessen the effects of air pollution on human health and pulmonary disease. Cooperation at a multi-national level will be required on the part of governments, industry, energy-based enterprises and the public working together to solve our air quality issues at the local, national and global level. PMID:26761628

  4. Environmental equity in air quality management: local and international implications for human health and climate change.

    PubMed

    O'Neill, Marie S; Kinney, Patrick L; Cohen, Aaron J

    2008-01-01

    The health burden of environmental exposures, including ambient air pollution and climate-change-related health impacts, is not equally distributed between or within regions and countries. These inequalities are currently receiving increased attention in environmental research as well as enhanced appreciation in environmental policy, where calls for environmental equity are more frequently heard. The World Health Organization (WHO) 2006 Global Update of the Air Quality Guidelines attempted to address the global-scale inequalities in exposures to air pollution and the burden of diseases due to air pollution. The guidelines stop short, however, of addressing explicitly the inequalities in exposure and adverse health effects within countries and urban areas due to differential distribution of sources of air pollution such as motor vehicles and local industry, and differences in susceptibility to the adverse health effects attributed to air pollution. These inequalities, may, however, be addressed in local air quality and land use management decisions. Locally, community-based participatory research can play an important role in documenting potential inequities and fostering corrective action. Research on environmental inequities will also benefit from current efforts to (1) better understand social determinants of health and (2) apply research evidence to reduce health disparities. Similarly, future research and policy action will benefit from stronger linkages between equity concerns related to health consequences of both air pollution exposure and climate change, since combustion products are important contributors to both of these environmental problems.

  5. Climate change impact on air quality in California

    NASA Astrophysics Data System (ADS)

    Mahmud, Abdullah Al

    California has persistent air quality problems that affect the health of millions of residents. Global climate change will affect long-term weather patterns in California with unknown consequences to air quality. This dissertation explores how climate change will influence intermediary weather patterns and how they will subsequently affect air quality in California. The statistical relationship between the daily 1-hr maximum measured ozone concentrations and the daily maximum upper air temperature (T850) was explored for California's two most heavily polluted air basins. The temperature-ozone correlation was combined with T850 values predicted by Princeton's Geophysical Fluid Dynamics Laboratory (GFDL) model to predict how climate change will affect ozone concentrations. The results suggest that by the year 2050 California would experience an additional 22--30 days year-1 and 6--13 days year-1 with ozone concentrations ≥90 ppb under the IPCC A2 and B1 emissions scenarios (assuming emissions of criteria pollutants in California remained at 1990--2004 levels). Output from the NCAR/DOE Parallel Climate Model (PCM) generated under the "business as usual" global emissions scenario was downscaled to regional scales using the Weather Research and Forecasting (WRF) model followed by air quality simulations using the UCD/CIT airshed model. The air quality simulations were carried out for the entire state of California with a resolution of 8 km for the years 2000--06 (present climate) and 2047--53 (future climate). Averaging predictions from over 2000 simulation days suggest that annual average PM2.5 concentrations will decrease by ˜0.6--1.9 mug m-3 in coastal and central Los Angeles and increase by ˜0.9--1.3 mug m-3 at locations within the San Joaquin Valley (SJV) and the Sacramento Valley (SACV). A corresponding analysis of the annual variability showed that the 95% confidence interval spans zero (meaning no change due to climate). Similar analysis was carried out for

  6. "Air pollution in Delhi: Its Magnitude and Effects on Health".

    PubMed

    Rizwan, Sa; Nongkynrih, Baridalyne; Gupta, Sanjeev Kumar

    2013-01-01

    Air pollution is responsible for many health problems in the urban areas. Of late, the air pollution status in Delhi has undergone many changes in terms of the levels of pollutants and the control measures taken to reduce them. This paper provides an evidence-based insight into the status of air pollution in Delhi and its effects on health and control measures instituted. The urban air database released by the World Health Organization in September 2011 reported that Delhi has exceeded the maximum PM10 limit by almost 10-times at 198 μg/m3. Vehicular emissions and industrial activities were found to be associated with indoor as well as outdoor air pollution in Delhi. Studies on air pollution and mortality from Delhi found that all-natural-cause mortality and morbidity increased with increased air pollution. Delhi has taken several steps to reduce the level of air pollution in the city during the last 10 years. However, more still needs to be done to further reduce the levels of air pollution.

  7. Why business wants the Clean Air Act changed

    SciTech Connect

    Marth, D.

    1982-06-01

    New legislation to modify the Clean Air Act is designed to eliminate the cumbersome requirements that constrain economic growth without lowering present air standards. Environmentalists reject the Luken bill, however, in favor of only fine-tuning the existing Clean Air Act. Ignorance of how the complicated Act works has hampered its implementation by industry. The two sides appear irreconcilable as the debate focuses on the tradeoffs of jobs versus air quality. The Luken bill would ease auto emission requirements enough to lower car prices and reduce unemployment. Environmentalists challenge that claim and seek to tighten specific controls that will reduce the effects of acid rain. President Reagan favors the Luken bill, but political considerations will probably keep the battle concentrated in the House committee. Industry leaders are counting on public pressure to improve both the Act and the economy. (DCK)

  8. Changes in airborne fungi from the outdoors to indoor air; large HVAC systems in nonproblem buildings in two different climates.

    PubMed

    Kemp, P C; Neumeister-Kemp, H G; Esposito, B; Lysek, G; Murray, F

    2003-01-01

    Little is known about the changes in occurrence and distribution of airborne fungi as they are transported in the airstream from the outdoor air through the heating, ventilation, and air conditioning (HVAC) system to the indoor air. To better understand this, airborne fungi were analyzed in the HVAC systems of two large office buildings in different climate zones. Fungal samples were taken in each of the walk-in chambers of the HVAC systems using a six-stage Andersen Sampler with malt extract agar. Results showed that fungal species changed with different locations in the HVAC systems. The outdoor air intake produced the greatest filtration effect for both the counts and species of outdoor air fungi. The colony forming unit (CFU) counts and species diversity was further reduced in the air directly after the filters. The cooling coils also had a substantial filtration effect. However, in room air the CFU counts were double and the mixture of fungal species was different from the air leaving the HVAC system at the supply air outlet in most locations. Diffusion of outdoor air fungi to the indoors did not explain the changes in the mixture of airborne fungi from the outdoor air to the indoor air, and some of the fungi present in the indoor air did not appear to be transported indoors by the HVAC systems.

  9. U.S. Air Quality and Health Benefits from Avoided Climate Change under Greenhouse Gas Mitigation.

    PubMed

    Garcia-Menendez, Fernando; Saari, Rebecca K; Monier, Erwan; Selin, Noelle E

    2015-07-07

    We evaluate the impact of climate change on U.S. air quality and health in 2050 and 2100 using a global modeling framework and integrated economic, climate, and air pollution projections. Three internally consistent socioeconomic scenarios are used to value health benefits of greenhouse gas mitigation policies specifically derived from slowing climate change. Our projections suggest that climate change, exclusive of changes in air pollutant emissions, can significantly impact ozone (O3) and fine particulate matter (PM2.5) pollution across the U.S. and increase associated health effects. Climate policy can substantially reduce these impacts, and climate-related air pollution health benefits alone can offset a significant fraction of mitigation costs. We find that in contrast to cobenefits from reductions to coemitted pollutants, the climate-induced air quality benefits of policy increase with time and are largest between 2050 and 2100. Our projections also suggest that increasing climate policy stringency beyond a certain degree may lead to diminishing returns relative to its cost. However, our results indicate that the air quality impacts of climate change are substantial and should be considered by cost-benefit climate policy analyses.

  10. Climate change, extreme weather events, air pollution and respiratory health in Europe.

    PubMed

    De Sario, M; Katsouyanni, K; Michelozzi, P

    2013-09-01

    Due to climate change and other factors, air pollution patterns are changing in several urbanised areas of the world, with a significant effect on respiratory health both independently and synergistically with weather conditions; climate scenarios show Europe as one of the most vulnerable regions. European studies on heatwave episodes have consistently shown a synergistic effect of air pollution and high temperatures, while the potential weather-air pollution interaction during wildfires and dust storms is unknown. Allergen patterns are also changing in response to climate change, and air pollution can modify the allergenic potential of pollens, especially in the presence of specific weather conditions. The underlying mechanisms of all these interactions are not well known; the health consequences vary from decreases in lung function to allergic diseases, new onset of diseases, exacerbation of chronic respiratory diseases, and premature death. These multidimensional climate-pollution-allergen effects need to be taken into account in estimating both climate and air pollution-related respiratory effects, in order to set up adequate policy and public health actions to face both the current and future climate and pollution challenges.

  11. Effects of Indoor Air Pollutants on Atopic Dermatitis

    PubMed Central

    Kim, JaKyoung; Kim, HyungJin; Lim, DaeHyun; Lee, Young-Kyu; Kim, Jeong Hee

    2016-01-01

    The increasing prevalence of atopic dermatitis (AD) is associated with variations in indoor environments. In Korea, many inner walls of homes are covered with wallpaper: such walls emit indoor air pollutants, including volatile organic compounds (VOCs) and formaldehyde. This randomized, double-blind study investigated the effects of wallpaper on indoor air quality and AD. Thirty-one children (aged three to eight years) with moderate AD were assigned to environmentally-friendly (EF) and polyvinyl chloride (PVC) wallpaper groups. Indoor air concentrations of VOCs, natural VOCs (NVOCs), formaldehyde, and total suspended bacteria were measured before and two (W2) and eight weeks (W8) after wallpapering. Scoring Atopic Dermatitis (SCORAD) evaluations and blood tests were performed during the same period. The EF wallpaper and PVC wallpaper groups showed similar trends in the changes in total VOCs (TVOC) and formaldehyde content in the indoor air. However, the EF wallpaper group showed more improvement on the SCORAD at W2 and W8 than the PVC wallpaper group. The SCORAD index was positively correlated with several indoor air pollutants. Further, the SCORAD index and NVOC % were negatively correlated. Improved SCORAD index and effects of wallpapering on indoor air quality improvements occurred within a short period of time in both groups. We believe that NVOCs in indoor air after EF wallpapering have a beneficial effect on health. PMID:27941696

  12. Health effects of outdoor air pollution

    PubMed Central

    Abelsohn, Alan; Stieb, Dave M.

    2011-01-01

    Abstract Objective To inform family physicians about the health effects of air pollution and to provide an approach to counseling vulnerable patients in order to reduce exposure. Sources of information MEDLINE was searched using terms relevant to air pollution and its adverse effects. We reviewed English-language articles published from January 2008 to December 2009. Most studies provided level II evidence. Main message Outdoor air pollution causes substantial morbidity and mortality in Canada. It can affect both the respiratory system (exacerbating asthma and chronic obstructive pulmonary disease) and the cardiovascular system (triggering arrhythmias, cardiac failure, and stroke). The Air Quality Health Index (AQHI) is a new communication tool developed by Health Canada and Environment Canada that indicates the level of health risk from air pollution on a scale of 1 to 10. The AQHI is widely reported in the media, and the tool might be of use to family physicians in counseling high-risk patients (such as those with asthma, chronic obstructive pulmonary disease, or cardiac failure) to reduce exposure to outdoor air pollution. Conclusion Family physicians can use the AQHI and its health messages to teach patients with asthma and other high-risk patients how to reduce health risks from air pollution. PMID:21841106

  13. Estimation of potential evapotranspiration from extraterrestrial radiation, air temperature and humidity to assess future climate change effects on the vegetation of the Northern Great Plains, USA

    USGS Publications Warehouse

    King, David A.; Bachelet, Dominique M.; Symstad, Amy J.; Ferschweiler, Ken; Hobbins, Michael

    2014-01-01

    The potential evapotranspiration (PET) that would occur with unlimited plant access to water is a central driver of simulated plant growth in many ecological models. PET is influenced by solar and longwave radiation, temperature, wind speed, and humidity, but it is often modeled as a function of temperature alone. This approach can cause biases in projections of future climate impacts in part because it confounds the effects of warming due to increased greenhouse gases with that which would be caused by increased radiation from the sun. We developed an algorithm for linking PET to extraterrestrial solar radiation (incoming top-of atmosphere solar radiation), as well as temperature and atmospheric water vapor pressure, and incorporated this algorithm into the dynamic global vegetation model MC1. We tested the new algorithm for the Northern Great Plains, USA, whose remaining grasslands are threatened by continuing woody encroachment. Both the new and the standard temperature-dependent MC1 algorithm adequately simulated current PET, as compared to the more rigorous PenPan model of Rotstayn et al. (2006). However, compared to the standard algorithm, the new algorithm projected a much more gradual increase in PET over the 21st century for three contrasting future climates. This difference led to lower simulated drought effects and hence greater woody encroachment with the new algorithm, illustrating the importance of more rigorous calculations of PET in ecological models dealing with climate change.

  14. MODELING THE IMPACT OF AIR POLLUTION ON GLOBAL CLIMATE CHANGE

    EPA Science Inventory

    Tropospheric ozone (O3) and aerosols have major effects on climate and are the two air pollutants of most concern in the developed world. O3 is a major greenhouse gas (GHG) and light-absorbing aerosols such as black carbon (BC) also contribute to global warm...

  15. Ventilation System Effectiveness and Tested Indoor Air Quality Impacts

    SciTech Connect

    Rudd, A.; Bergey, D.

    2014-02-01

    Ventilation system effectiveness testing was conducted at two unoccupied, single-family, detached lab homes at the University of Texas - Tyler. Five ventilation system tests were conducted with various whole-building ventilation systems. Multizone fan pressurization testing characterized building and zone enclosure leakage. PFT testing showed multizone air change rates and interzonal airflow. Cumulative particle counts for six particle sizes, and formaldehyde and other Top 20 VOC concentrations were measured in multiple zones. The testing showed that single-point exhaust ventilation was inferior as a whole-house ventilation strategy. It was inferior because the source of outside air was not direct from outside, the ventilation air was not distributed, and no provision existed for air filtration. Indoor air recirculation by a central air distribution system can help improve the exhaust ventilation system by way of air mixing and filtration. In contrast, the supply and balanced ventilation systems showed that there is a significant benefit to drawing outside air from a known outside location, and filtering and distributing that air. Compared to the Exhaust systems, the CFIS and ERV systems showed better ventilation air distribution and lower concentrations of particulates, formaldehyde and other VOCs. System improvement percentages were estimated based on four System Factor Categories: Balance, Distribution, Outside Air Source, and Recirculation Filtration. Recommended System Factors could be applied to reduce ventilation fan airflow rates relative to ASHRAE Standard 62.2 to save energy and reduce moisture control risk in humid climates. HVAC energy savings were predicted to be 8-10%, or $50-$75/year.

  16. Ventilation System Effectiveness and Tested Indoor Air Quality Impacts

    SciTech Connect

    Rudd, Armin; Bergey, Daniel

    2014-02-01

    In this project, Building America research team Building Science Corporation tested the effectiveness of ventilation systems at two unoccupied, single-family, detached lab homes at the University of Texas - Tyler. Five ventilation system tests were conducted with various whole-building ventilation systems. Multizone fan pressurization testing characterized building and zone enclosure leakage. PFT testing showed multizone air change rates and interzonal airflow. Cumulative particle counts for six particle sizes, and formaldehyde and other Top 20 VOC concentrations were measured in multiple zones. The testing showed that single-point exhaust ventilation was inferior as a whole-house ventilation strategy. This was because the source of outside air was not direct from outside, the ventilation air was not distributed, and no provision existed for air filtration. Indoor air recirculation by a central air distribution system can help improve the exhaust ventilation system by way of air mixing and filtration. In contrast, the supply and balanced ventilation systems showed that there is a significant benefit to drawing outside air from a known outside location, and filtering and distributing that air. Compared to the exhaust systems, the CFIS and ERV systems showed better ventilation air distribution and lower concentrations of particulates, formaldehyde and other VOCs. System improvement percentages were estimated based on four system factor categories: balance, distribution, outside air source, and recirculation filtration. Recommended system factors could be applied to reduce ventilation fan airflow rates relative to ASHRAE Standard 62.2 to save energy and reduce moisture control risk in humid climates. HVAC energy savings were predicted to be 8-10%, or $50-$75/year.

  17. Summary Report for the Workshop on Integrating Climate Change Adaption into Air Quality Decision Making

    EPA Science Inventory

    Over the past few decades, air quality planners have forecasted future air pollution levels based on information about changing emissions from stationary and mobile sources, population trends, transportation demand, natural sources of emissions, and other pressures on air quality...

  18. Air pollution holiday effect in metropolitan Kaohsiung

    NASA Astrophysics Data System (ADS)

    Tan, P.; Chen, P. Y.

    2014-12-01

    Different from Taipei, the metropolitan Kaohsiung which is a coastal and industrial city has the major pollution sources from stationary sources such as coal-fired power plants, petrochemical facilities and steel plants, rather than mobile sources. This study was an attempt to conduct a comprehensive and systematical examination of the holiday effect, defined as the difference in air pollutant concentrations between holiday and non-holiday periods, over the Kaohsiung metropolitan area. We documented evidence of a "holiday effect", where concentrations of NOx, CO, NMHC, SO2 and PM10 were significantly different between holidays and non-holidays, in the Kaohsiung metropolitan area from daily surface measurements of seven air quality monitoring stations of the Taiwan Environmental Protection Administration during the Chinese New Year (CNY) and non-Chinese New Year (NCNY) periods of 1994-2010. Concentrations of the five pollutants were lower in the CNY than in the NCNY period, however, that of O3 was higher in the CNY than in the NCNY period and had no holiday effect. The exclusion of the bad air quality day (PSI > 100) and the Lantern Festival Day showed no significant effects on the holiday effects of air pollutants. Ship transportation data of Kaohsiung Harbor Bureau showed a statistically significant difference in the CNY and NCNY period. This difference was consistent with those found in air pollutant concentrations of some industrial and general stations in coastal areas, implying the possible impact of traffic activity on the air quality of coastal areas. Holiday effects of air pollutants over the Taipei metropolitan area by Tan et al. (2009) are also compared.

  19. Effect of road blockages on local air pollution during the Hong Kong protests and its implications for air quality management.

    PubMed

    Brimblecombe, Peter; Ning, Zhi

    2015-12-01

    Roadside air quality in urban areas is largely affected by the traffic emissions. Changes in emissions and transport control policy are often assumed to yield benefits in air quality, but have often not always been effective in producing perceptible improvements due to the complexity of meteorological conditions. This study evaluates the air quality before, during and after a temporary roadway blockage event in Hong Kong that took place during Hong Kong protests from late September to mid-December, 2014. The local regulatory air quality monitoring data from both roadside and general ambient stations were used to assess the impact of roadway blockages on the air quality. There was a public perception of improved air quality, but analysis of the data shows the changes can be difficult to discern. This study showed some benefits deriving from road blockages on the local air quality, but the impact was not always apparent because of seasonal variation in meteorological conditions and synoptic transport of pollutants. The finding suggests care is required before making policy changes based on claimed benefits of shifting transport routes. The study highlights the needs to remove seasonal and meteorological change when examining air pollution data to develop strategies to improve air quality.

  20. Climate change and air pollution jointly creating nightmare for tourism industry.

    PubMed

    Sajjad, Faiza; Noreen, Umara; Zaman, Khalid

    2014-11-01

    The objective of the study is to examine the long-run and causal relationship between climate change (i.e., greenhouse gas emissions, hydrofluorocarbons, per fluorocarbons, and sulfur hexafluoride), air pollution (i.e., methane emissions, nitrous oxide emissions, and carbon dioxide emissions), and tourism development indicators (i.e., international tourism receipts, international tourism expenditures, natural resource depletion, and net forest depletion) in the World's largest regions. The aggregate data is used for robust analysis in the South Asia, the Middle East and North Africa, sub-Saharan Africa, and East Asia and the Pacific regions, over a period of 1975-2012. The results show that climatic factors and air pollution have a negative impact on tourism indicators in the form of deforestation and natural resource depletion. The impact is evident, as we have seen the systematic eroding of tourism industry, due to severe changes in climate and increasing strain of air pollution. There are several channels of cause-effect relationship between the climatic factors, air pollution, and tourism indicators in the World's region. The study confirms the unidirectional, bidirectional, and causality independent relationship between climatic factors, air pollution, and tourism indicators in the World. It is conclusive that tourism industry is facing all time bigger challenges of reduce investment, less resources, and minor importance from the government agencies because of the two broad challenges, i.e., climate change and air pollution, putting them in a dismal state.

  1. Health Impacts of Air Pollution Under a Changing Climate

    NASA Astrophysics Data System (ADS)

    Kinney, P. L.; Knowlton, K.; Rosenthal, J.; Hogrefe, C.; Rosenzweig, C.; Solecki, W.

    2003-12-01

    Outdoor air pollution remains a serious public health problem in cities throughout the world. In the US, despite considerable progress in reducing emissions over the past 30 years, as many as 50,000 premature deaths each year have been attributed to airborne particulate matter alone. Tropospheric ozone has been associated with increased daily mortality and hospitalization rates, and with a variety of related respiratory problems. Weather plays an important role in the transport and transformation of air pollution. In particular, a warming climate is likely to promote the atmospheric reactions that are responsible for ozone and secondary aerosol production, as well as increasing emissions of many of their volatile precursors. Increasingly, efforts to address urban air pollution problems throughout the world will be complicated by trends and variability in climate. The New York Climate and Health Project (NYCHP) is developing and applying tools for integrated assessment of health impacts from air pollution and heat associated with climate and land-use changes in the New York City metropolitan region. Global climate change is modeled over the 21st century based on the Intergovernmental Panel on Climate Change (IPCC) A2 greenhouse gas emissions scenario using the Goddard Institute for Space Studies (GISS) Global Atmosphere-Ocean Model (GCM). Meteorological fields are downscaled to a 36 km grid over the eastern US using the Penn State/NCAR MM5 mesoscale meteorological model. MM5 results are then used as input to the Community Multiscale Air Quality (CMAQ) model for simulating air quality, with emissions based on the Sparse Matrix Operator Kernel Emissions Modeling System (SMOKE). To date, simulations have been performed for five summer seasons each during the 1990s and the 2050s. An evaluation of the present-day climate and air quality predictions indicates that the modeling system largely captures the observed climate-ozone system. Analysis of future-year predictions

  2. Adapting Buildings for Indoor Air Quality in a Changing Climate

    EPA Pesticide Factsheets

    Climate change presents many challenges, including the production of severe weather events. These events and efforts to minimize their effects through weatherization can adversely affect indoor environments.

  3. The effects of air leaks on solar air heating systems

    NASA Technical Reports Server (NTRS)

    Elkin, R.; Cash, M.

    1979-01-01

    This paper presents the results of an investigation to determine the effects of leakages in collector and duct work on the system performance of a typical single-family residence solar air heating system. Positive (leakage out) and negative (leakage in) pressure systems were examined. Collector and duct leakage rates were varied from 10 to 30 percent of the system flow rate. Within the range of leakage rates investigated, solar contribution to heated space and domestic hot water loads was found to be reduced up to 30 percent from the no-leak system contribution with duct leakage equally divided between supply and return duct; with supply duct leakage greater than return leakage a reduction of up to 35 percent was noted. The negative pressure system exhibited a reduction in solar contribution somewhat larger than the positive pressure system for the same leakage rates.

  4. Climatic effects of air pollutants over china: A review

    NASA Astrophysics Data System (ADS)

    Liao, Hong; Chang, Wenyuan; Yang, Yang

    2015-01-01

    Tropospheric ozone (O3) and aerosols are major air pollutants in the atmosphere. They have also made significant contributions to radiative forcing of climate since preindustrial times. With its rapid economic development, concentrations of air pollutants are relatively high in China; hence, quantifying the role of air pollutants in China in regional climate change is especially important. This review summarizes existing knowledge with regard to impacts of air pollutants on climate change in China and defines critical gaps needed to reduce the associated uncertainties. Measured monthly, seasonal, and annual mean surface-layer concentrations of O3 and aerosols over China are compiled in this work, with the aim to show the magnitude of concentrations of O3 and aerosols over China and to provide datasets for evaluation of model results in future studies. Ground-based and satellite measurements of O3 column burden and aerosol optical properties, as well as model estimates of radiative forcing by tropospheric O3 and aerosols are summarized. We also review regional and global modeling studies that have investigated climate change driven by tropospheric O3 and/or aerosols in China; the predicted sign and magnitude of the responses in temperature and precipitation to O3/aerosol forcings are presented. Based on this review, key priorities for future research on the climatic effects of air pollutants in China are highlighted.

  5. Climate change and the meteorological drivers of PM air pollution: Understanding U.S. particulate matter concentrations in a changing climate

    EPA Science Inventory

    Particulate matter (PM) air pollution is a serious public health issue for the United States. While there is a growing body of evidence that climate change will partially counter the effectiveness of future precursor emission reductions to reduce ozone (O3) air pollution, the lin...

  6. Respiratory effects of outdoor air pollution

    SciTech Connect

    Griffith, D.E.; Levin, J.L. )

    1989-10-01

    Outdoor air pollution adversely affects human health and the quality of the environment. However, epidemiologic studies of these effects are difficult to control because of confounding variables such as age and cigarette smoking and the difficulty in estimating doses of pollutants. Drs Griffith and Levin discuss the relationship between major types of pollutants and increased morbidity and mortality from respiratory disease.35 references.

  7. Changes in the frequency of extreme air pollution events over the Eastern United States and Europe

    NASA Astrophysics Data System (ADS)

    Rieder, H. E.; Fiore, A. M.; Polvani, L. M.; Lamarque, J.-F.; Fang, Y.; Staehelin, J.

    2012-04-01

    Over the past few decades, thresholds for national air quality standards, intended to protect public health and welfare, have been lowered repeatedly. At the same time observations, over Europe and the Eastern U.S., demonstrate that extreme air pollution events (high O3 and PM2.5) are typically associated with stagnation events. Recent work showed that in a changing climate high air pollution events are likely to increase in frequency and duration. Within this work we examine meteorological and surface ozone observations from CASTNet over the U.S. and EMEP over Europe. With innovative statistical tools - i.e., statistics of extremes (EVT) - we analyze the frequency distribution of extreme air pollution events over the Eastern United States and Europe. The upper tail of observed values at individual stations (e.g., within the CASTNet), i.e., the extremes (maximum daily 8-hour average (MDA8) O3>60ppb) are poorly described by a Gaussian distribution. However, further analysis showed that applying Peak-Over-Threshold-models, better capture the extremes and allows us to estimate return levels of pollution events above certain threshold values of interest. The results show that changes in national ambient air quality standards had significant effect on the occurrence frequency of high air pollution episodes.

  8. Negative air ion effects on human performance and physiological condition.

    PubMed

    Buckalew, L W; Rizzuto, A P

    1984-08-01

    Beneficial effects of exposure to negative air ions have been suggested, to include improved performance, mood, attention, and physiological condition. Existing support is clouded by methodological problems of control and standardization in treatment and equipment. This study investigated effects of negative ions produced by a commercially marketed air purification device on grip magnitude, coding, motor dexterity, reaction time, tracking, pulse, blood pressure, and temperature. Two groups of 12 males were exposed to 6 continuous h of either negative or "normal" ion environments under a double blind condition. Repeated measures (0,3,6 h) on each variable were obtained. MANOVA applied to change scores revealed no differences between groups, and 0 vs. 3 and 0 vs. 6-h group differences showed no significant alteration in any measure. Negative ions generated by an air purification device were concluded to produce no general or specific alteration of cognitive or psychomotor performance or physiological condition.

  9. Regional volume changes in canine lungs suspended in air

    NASA Technical Reports Server (NTRS)

    Abbrecht, Peter H.; Kyle, Richard R.; Bryant, Howard J.; Feuerstein, Irwin

    1995-01-01

    The purpose of this study was to determine the effect of the absence of a pleural pressure gradient (simulating the presumed condition found in microgravity) upon regional expansion of the lung. We attempted to produce a uniform pressure over the surface of the lung by suspending excised lungs in air. Such studies should help determine whether or not the absence of a pleural pressure gradient leads to uniform ventilation. A preparation in which there is no pleural pressure gradient should also be useful in studying non-gravitational effects on ventilation distribution.

  10. Spectra Handling from AIRS and IRIS for Climate Change Research

    NASA Astrophysics Data System (ADS)

    Jiang, Y.; Lau, M.; Aumann, H. H.; Yung, Y. L.

    2010-12-01

    Outgoing longwave radiation (OLR) measurements over a long period from satellites provide valuable information for the climate change research. Due to the different coverage, spectral resolution and instrument sensitivities, the data comparisons between different satellites could be problematic and possible artifacts could be easily introduced. In this paper, we have analyzed the data taken by IRIS in 1970 and by AIRS from 2002 to 2010. IRIS (Prabhakara, 1988) was a Fourier transform spectrometer (FTS) and it flew on the NASA Nimbus 4 satellite which was launched in April 1970 into an 1100km altitude sun-synchronous polar orbit. It collected data from the nadir track between 400cm-1 and 1600 cm-1 from April 1970 until January 1971. AIRS (Aumann, 2003) is a grating spectrometer launched on the EOS-Aqua satellite in May 2002 and it measures spectra from 650cm-1 to 2700cm-1. AIRS scans to ±49.5o cross track as the satellite moves forwards taking 90 spectra each with an instantaneous field of view of 1.1o in a row perpendicular to the direction of motion of the satellite. This results in a ground footprint of 13km diameter at nadir. In this paper, we analyzed the spectra between 650 cm-1 and 1350 cm-1 for nadir view footprints in order to match the IRIS’s measurements. Most of the possible sources of error or biases have been carefully handled, these include the errors from the data editing, spatial coverage, missing data (spatial gap), and spectral resolution, spectra frequency shift due to the fields of view, sea surface temperature fluctuations, clear sky determination, and spectra response function symmetry. It is extremely important when comparing spectra in the high slope spectra regions where possible large artifacts could be introduced. We have used a radiative model to simulate the spectra as observed in both IRIS and AIRS by using US Standard Atmospheric Profiles. The tropospheric warming and stratospheric warming are introduced in the model as well. The

  11. Considering Climate Change in U.S. Air Quality Management

    SciTech Connect

    Hogrefe, C.; Leung, Lai R.; Mickley, L. J.; Hunt, Sherri W.; Winner, D. A.

    2005-10-01

    Despite the challenges in linking global and regional processes, evidence from recent studies suggests that the effects of a changing climate should not be neglected when planning for the future attainment of regional-scale ozone standards such as the U.S. NAAQS. Research underway should provide insight regarding the impact of climate change on Ozone and PM2.5 and of the complex interaction of climate, land-use, and technology change.

  12. The Effects of Air Pollution and Temperature on COPD

    PubMed Central

    Hansel, Nadia N.; McCormack, Meredith C.; Kim, Victor

    2016-01-01

    Chronic Obstructive Pulmonary Disease (COPD) affects 12–16 million people in the United States and is the third-leading cause of death. In developed countries, smoking is the greatest risk factor for the development of COPD, but other exposures also contribute to the development and progression of the disease. Several studies suggest, though are not definitive, that outdoor air pollution exposure is linked to the prevalence and incidence of COPD. Among individuals with COPD, outdoor air pollutants are associated with loss of lung function and increased respiratory symptoms. In addition, outdoor air pollutants are also associated with COPD exacerbations and mortality. There is much less evidence for the impact of indoor air on COPD, especially in developed countries in residences without biomass exposure. The limited existing data suggests that indoor particulate matter and nitrogen dioxide concentrations are linked to increased respiratory symptoms among patients with COPD. In addition, with the projected increases in temperature and extreme weather events in the context of climate change there has been increased attention to the effects of heat exposure. Extremes of temperature—both heat and cold—have been associated with increased respiratory morbidity in COPD. Some studies also suggest that temperature may modify the effect of pollution exposure and though results are not conclusive, understanding factors that may modify susceptibility to air pollution in patients with COPD is of utmost importance. PMID:26683097

  13. The Air Toxics Health Effects Database (ATHED).

    PubMed

    Woodall, George M; Smith, Roy L

    2008-11-15

    The Air Toxics Health Effects Database (ATHED) is currently used by the EPA's Office of Air Quality Planning and Standards (OAQPS) to support risk assessments for the Residual Risk Program. An assessment of the residual risk is required to be performed at a specified time (typically 8 years) following the promulgation of a technology-based Maximum Achievable Control Technologies (MACT) standard. The goal of the Residual Risk Program is to assure that the risk that remains after MACT standards are implemented (i.e., the "residual risk") is acceptable, and if not, to propose additional regulations to mitigate those risks. ATHED maintains all available reference values for each chemical as separate data records, and includes values for all exposure durations (acute, short-term, subchronic and chronic). These values are used as benchmarks to determine acceptable exposure levels to the hazardous air pollutants (HAPs) listed in Section 112 of the Clean Air Act. ATHED also provides useful background information on the uncertainty and/or modifying factors that were applied in the derivation of each reference value, as well as the point of departure and the critical study/studies. To facilitate comparisons across durations for a specific chemical, ATHED data can be graphically presented.

  14. Air Pollution

    MedlinePlus

    ... of Climate Change on Children's Health: Session Two: Air Quality Impacts MODERATOR: Susan Anenberg, EPA Meredith McCormack, Johns ... University • Effects of Climate Change on Children’s Health: Air Quality Impacts Frederica Perera, Columbia University • Air quality Impacts ...

  15. Air

    MedlinePlus

    ... do to protect yourself from dirty air . Indoor air pollution and outdoor air pollution Air can be polluted indoors and it can ... this chart to see what things cause indoor air pollution and what things cause outdoor air pollution! Indoor ...

  16. Regional change in snow water equivalent-surface air temperature relationship over Eurasia during boreal spring

    NASA Astrophysics Data System (ADS)

    Wu, Renguang; Chen, Shangfeng

    2016-10-01

    Present study investigates local relationship between surface air temperature and snow water equivalent (SWE) change over mid- and high-latitudes of Eurasia during boreal spring. Positive correlation is generally observed around the periphery of snow covered region, indicative of an effect of snow on surface temperature change. In contrast, negative correlation is usually found over large snow amount area, implying a response of snow change to wind-induced surface temperature anomalies. With the seasonal retreat of snow covered region, region of positive correlation between SWE and surface air temperature shifts northeastward from March to May. A diagnosis of surface heat flux anomalies in April suggests that the snow impact on surface air temperature is dominant in east Europe and west Siberia through modulating surface shortwave radiation. In contrast, atmospheric effect on SWE is important in Siberia and Russia Far East through wind-induced surface sensible heat flux change. Further analysis reveals that atmospheric circulation anomalies in association with snowmelt over east Siberia may be partly attributed to sea surface temperature anomalies in the North Atlantic and the atmospheric circulation anomaly pattern associated with snowmelt over Russia Far East has a close association with the Arctic Oscillation.

  17. Global topics and novel approaches in the study of air pollution, climate change and forest ecosystems.

    PubMed

    Sicard, Pierre; Augustaitis, Algirdas; Belyazid, Salim; Calfapietra, Carlo; de Marco, Alessandra; Fenn, Mark; Bytnerowicz, Andrzej; Grulke, Nancy; He, Shang; Matyssek, Rainer; Serengil, Yusuf; Wieser, Gerhard; Paoletti, Elena

    2016-06-01

    Research directions from the 27th conference for Specialists in Air Pollution and Climate Change Effects on Forest Ecosystems (2015) reflect knowledge advancements about (i) Mechanistic bases of tree responses to multiple climate and pollution stressors, in particular the interaction of ozone (O3) with nitrogen (N) deposition and drought; (ii) Linking genetic control with physiological whole-tree activity; (iii) Epigenetic responses to climate change and air pollution; (iv) Embedding individual tree performance into the multi-factorial stand-level interaction network; (v) Interactions of biogenic and anthropogenic volatile compounds (molecular, functional and ecological bases); (vi) Estimating the potential for carbon/pollution mitigation and cost effectiveness of urban and peri-urban forests; (vii) Selection of trees adapted to the urban environment; (viii) Trophic, competitive and host/parasite relationships under changing pollution and climate; (ix) Atmosphere-biosphere-pedosphere interactions as affected by anthropospheric changes; (x) Statistical analyses for epidemiological investigations; (xi) Use of monitoring for the validation of models; (xii) Holistic view for linking the climate, carbon, N and O3 modelling; (xiii) Inclusion of multiple environmental stresses (biotic and abiotic) in critical load determinations; (xiv) Ecological impacts of N deposition in the under-investigated areas; (xv) Empirical models for mechanistic effects at the local scale; (xvi) Broad-scale N and sulphur deposition input and their effects on forest ecosystem services; (xvii) Measurements of dry deposition of N; (xviii) Assessment of evapotranspiration; (xix) Remote sensing assessment of hydrological parameters; and (xx) Forest management for maximizing water provision and overall forest ecosystem services. Ground-level O3 is still the phytotoxic air pollutant of major concern to forest health. Specific issues about O3 are: (xxi) Developing dose-response relationships and

  18. Measurement of inflammation and oxidative stress following drastic changes in air pollution during the Beijing Olympics: a panel study approach.

    PubMed

    Kipen, Howard; Rich, David; Huang, Wei; Zhu, Tong; Wang, Guangfa; Hu, Min; Lu, Shou-en; Ohman-Strickland, Pamela; Zhu, Ping; Wang, Yuedan; Zhang, Jim Junfeng

    2010-08-01

    Ambient air pollution has been linked to cardiovascular and respiratory morbidity and mortality in epidemiology studies. Frequently, oxidative and nitrosative stress are hypothesized to mediate these pollution effects, however precise mechanisms remain unclear. This paper describes the methodology for a major panel study to examine air pollution effects on these and other mechanistic pathways. The study took place during the drastic air pollution changes accompanying the 2008 Olympics in Beijing, China. After a general description of air pollution health effects, we provide a discussion of panel studies and describe the unique features of this study that make it likely to provide compelling results. This study should lead to a clearer and more precise definition of the role of oxidative and nitrosative stress, as well as other mechanisms, in determining acute morbidity and mortality from air pollution exposure.

  19. Measurement of inflammation and oxidative stress following drastic changes in air pollution during the Beijing Olympics: a panel study approach

    PubMed Central

    Kipen, Howard; Rich, David; Huang, Wei; Zhu, Tong; Wang, Guangfa; Hu, Min; Lu, Shou-en; Ohman-Strickland, Pamela; Zhu, Ping; Wang, Yuedan; Zhang, Jim (Junfeng)

    2014-01-01

    Ambient air pollution has been linked to cardiovascular and respiratory morbidity and mortality in epidemiology studies. Frequently, oxidative and nitrosative stress are hypothesized to mediate these pollution effects, however precise mechanisms remain unclear. This paper describes the methodology for a major panel study to examine air pollution effects on these and other mechanistic pathways. The study took place during the drastic air pollution changes accompanying the 2008 Olympics in Beijing, China. After a general description of air pollution health effects, we provide a discussion of panel studies and describe the unique features of this study that make it likely to provide compelling results. This study should lead to a clearer and more precise definition of the role of oxidative and nitrosative stress, as well as other mechanisms, in determining acute morbidity and mortality from air pollution exposure. PMID:20716299

  20. Social Justice Is in the Air: Teaching Climate Change and Air Pollution with Scientific and Social Inquiry

    NASA Astrophysics Data System (ADS)

    Hahnenberger, M.

    2014-12-01

    The intersection of environmental with social problems is a growing area of concern for scientists, policy makers, and citizens. Climate change and air pollution are two current environmental issues holding the public's attention which require collaboration of all stakeholders to create meaningful solutions. General education science courses are critical venues to engage students in the intersection of science with society. Effective teaching methods for these intersections include case studies, gallery walks, and town hall meetings. A case study from California explores how air quality has greatly improved in Los Angeles in the past 20 years, however residents of neighborhoods with lower socioeconomic status are still exposed to high levels of air pollutants. Students analyze scientific and health data to develop understanding and expertise in the problem, and are then tasked with developing a cost-benefit analysis of solutions. Gallery walks can be used to connect natural phenomena, such as hurricanes and severe weather, with their human impacts. Students bring their personal experiences with disasters and recovery to analyze how societies should deal with the changing climate and weather risks in their region, the country, or across the world. Town hall meetings allow students to gain expertise and perspective while embodying a role as a particular stakeholder in a climate mitigation or adaptation issue. A successful application of this method is a discussion of whether a resort community should be rebuilt on a barrier island after being destroyed in a category 3 hurricane. Stakeholders which students take on as roles have included climate scientists, homeowners, emergency managers, meteorologists, and others. Including distinct connections to social issues in introductory science courses helps students to not only engage with the material in a deeper way, but also helps to create critical thinkers who will become better citizens for tomorrow.

  1. Air quality in postunification Erfurt, East Germany: associating changes in pollutant concentrations with changes in emissions.

    PubMed

    Ebelt, S; Brauer, M; Cyrys, J; Tuch, T; Kreyling, W G; Wichmann, H E; Heinrich, J

    2001-04-01

    The unification of East and West Germany in 1990 resulted in sharp decreases in emissions of major air pollutants. This change in air quality has provided an opportunity for a natural experiment to evaluate the health impacts of air pollution. We evaluated airborne particle size distribution and gaseous co-pollutant data collected in Erfurt, Germany, throughout the 1990s and assessed the extent to which the observed changes are associated with changes in the two major emission sources: coal burning for power production and residential heating, and motor vehicles. Continuous data for sulfur dioxide, total suspended particulates (TSP), nitric oxide, carbon monoxide, and meteorologic parameters were available for 1990-1999, and size-selective particle number and mass concentration measurements were made during winters of 1991 and 1998. We used hourly profiles of pollutants and linear regression analyses, stratified by year, weekday/weekend, and hour, using NO and SO(2) as markers of traffic- and heating-related combustion sources, respectively, to study the patterns of various particle size fractions. Supplementary data on traffic and heating-related sources were gathered to support hypotheses linking these sources with observed changes in ambient air pollution levels. Substantially decreased (19-91%) concentrations were observed for all pollutants, with the exception of particles in the 0.01-0.03 microm size range (representing the smallest ultrafine particles that were measured). The number concentration for these particles increased by 115% between 1991 and 1998. The ratio of these ultrafine particles to TSP also increased by more than 500%, indicating a dramatic change in the size distribution of airborne particles. Analysis of hourly concentration patterns indicated that in 1991, concentrations of SO(2) and larger particle sizes were related to residential heating with coal. These peaks were no longer evident in 1998 due to decreases in coal consumption and

  2. Air quality in postunification Erfurt, East Germany: associating changes in pollutant concentrations with changes in emissions.

    PubMed Central

    Ebelt, S; Brauer, M; Cyrys, J; Tuch, T; Kreyling, W G; Wichmann, H E; Heinrich, J

    2001-01-01

    The unification of East and West Germany in 1990 resulted in sharp decreases in emissions of major air pollutants. This change in air quality has provided an opportunity for a natural experiment to evaluate the health impacts of air pollution. We evaluated airborne particle size distribution and gaseous co-pollutant data collected in Erfurt, Germany, throughout the 1990s and assessed the extent to which the observed changes are associated with changes in the two major emission sources: coal burning for power production and residential heating, and motor vehicles. Continuous data for sulfur dioxide, total suspended particulates (TSP), nitric oxide, carbon monoxide, and meteorologic parameters were available for 1990-1999, and size-selective particle number and mass concentration measurements were made during winters of 1991 and 1998. We used hourly profiles of pollutants and linear regression analyses, stratified by year, weekday/weekend, and hour, using NO and SO(2) as markers of traffic- and heating-related combustion sources, respectively, to study the patterns of various particle size fractions. Supplementary data on traffic and heating-related sources were gathered to support hypotheses linking these sources with observed changes in ambient air pollution levels. Substantially decreased (19-91%) concentrations were observed for all pollutants, with the exception of particles in the 0.01-0.03 microm size range (representing the smallest ultrafine particles that were measured). The number concentration for these particles increased by 115% between 1991 and 1998. The ratio of these ultrafine particles to TSP also increased by more than 500%, indicating a dramatic change in the size distribution of airborne particles. Analysis of hourly concentration patterns indicated that in 1991, concentrations of SO(2) and larger particle sizes were related to residential heating with coal. These peaks were no longer evident in 1998 due to decreases in coal consumption and

  3. Investigation of air pollution and regional climate change due to anthropogenic aerosols

    NASA Astrophysics Data System (ADS)

    Nakata, Makiko; Sano, Itaru; Mukai, Sonoyo

    2016-10-01

    Increased emissions of anthropogenic aerosols associated with economic growth can lead to increased concentrations of hazardous air pollutants. In particular, large cities in East Asia have experienced numerous heavy haze episodes. Atmospheric aerosol distributions in East Asia are complex, being influenced by both natural phenomena and human activity, with urban areas in particular being dominated by fine anthropogenic aerosols released from diesel-powered vehicles and industrial activity. In Japan, air pollution levels have been reduced; nevertheless, in recent years, there is increasing concern regarding air pollution caused by fine particulate matter. The origins of air pollution were examined, focusing on the comparison between aerosol properties observed from satellites and that on the ground. Because of their short life spans, concentrations of anthropogenic aerosols are highest over the source regions, and as a result, the climatic impacts of anthropogenic aerosols are also found to be most pronounced in these regions. In this study, aerosol impacts on climate are assessed by numerical model simulations. The direct effects of aerosols include reduced solar radiation, and hence a decrease in surface temperatures. In addition to these changes in the radiation budget, aerosols have a significant potential to change cloud and precipitation fields. These climatic responses to aerosols can manifest far from their source regions with high industrial activities.

  4. Air pollution response to changing weather and power plant emissions in the eastern United States

    NASA Astrophysics Data System (ADS)

    Bloomer, Bryan Jaye

    Air pollution in the eastern United States causes human sickness and death as well as damage to crops and materials. NOX emission reduction is observed to improve air quality. Effectively reducing pollution in the future requires understanding the connections between smog, precursor emissions, weather, and climate change. Numerical models predict global warming will exacerbate smog over the next 50 years. My analysis of 21 years of CASTNET observations quantifies a climate change penalty. I calculate, for data collected prior to 2002, a climate penalty factor of ˜3.3 ppb O3/°C across the power plant dominated receptor regions in the rural, eastern U.S. Recent reductions in NOX emissions decreased the climate penalty factor to ˜2.2 ppb O3/°C. Prior to 1995, power plant emissions of CO2, SO2, and NOX were estimated with fuel sampling and analysis methods. Currently, emissions are measured with continuous monitoring equipment (CEMS) installed directly in stacks. My comparison of the two methods show CO 2 and SO2 emissions are ˜5% lower when inferred from fuel sampling; greater differences are found for NOX emissions. CEMS are the method of choice for emission inventories and commodity trading and should be the standard against which other methods are evaluated for global greenhouse gas trading policies. I used CEMS data and applied chemistry transport modeling to evaluate improvements in air quality observed by aircraft during the North American electrical blackout of 2003. An air quality model produced substantial reductions in O3, but not as much as observed. The study highlights weaknesses in the model as commonly used for evaluating a single day event and suggests areas for further investigation. A new analysis and visualization method quantifies local-daily to hemispheric-seasonal scale relationships between weather and air pollution, confirming improved air quality despite increasing temperatures across the eastern U.S. Climate penalty factors indicate

  5. Indoor air pollution: Acute adverse health effects and host susceptibility

    SciTech Connect

    Zummo, S.M.; Karol, M.H.

    1996-01-01

    Increased awareness of the poor quality of indoor air compared with outdoor air has resulted in a significant amount of research on the adverse health effects and mechanisms of action of indoor air pollutants. Common indoor air agents are identified, along with resultant adverse health effects, mechanisms of action, and likely susceptible populations. Indoor air pollutants range from biological agents (such as dust mites) to chemical irritants (such as nitrogen dioxide, carbon monoxide, sulfur dioxide, formaldehyde, and isocyanates). These agents may exert their effects through allergic as well as nonallergic mechanisms. While the public does not generally perceive poor indoor air quality as a significant health risk, increasing reports of illness related to indoor air and an expanding base of knowledge on the health effects of indoor air pollution are likely to continue pushing the issue to the forefront.

  6. Energy Solutions to Air Pollution and Climate Change in California

    SciTech Connect

    Jacobson, M.Z.; Dvorak, M.; Archer, C.L.; Hoste, G.

    2007-07-01

    Wind, solar, hydro, and geothermal power can be combined for baseload or load-matching power supply, particularly in combination with plug-in electric vehicles. California and the U.S. have significant wind resources. California's offshore resources were quantified. Interconnecting wind farms can convert about 1/3 of intermittent power to power with the same reliability as a coal-fired power plant. Wind-battery electric vehicles could reduce U.S. CO2 by 25.5%; solar-battery electric vehicles can reduce it by 23.4%. Corn-ethanol vehicles cannot practically reduce CO2 in the U.S. by more than 0.07-0.2%. Battery electric and hydrogen-fuel cell vehicles powered by renewable sources will eliminate 10,000-20,000 U.S. air pollution deaths each year. Ethanol vehicles will increase the death rate or cause no change. Wind turbines require 30 times less land than corn ethanol and 20 times less land than cellulosic ethanol for the same power.

  7. Air pollution effects due to deregulation of the electric industry

    NASA Astrophysics Data System (ADS)

    Davoodi, Khojasteh Riaz

    The Energy Policy Act of 1992 introduced the concept of open-access into the electric utility industry which allows privately-owned utilities to transmit power produced by non-utility generators and independent power producers (IPPs). In April 1996, the Federal Energy Regulatory Commission (FERC) laid down the final rules (Orders No. 888 & No. 889), which required utilities to open their transmission lines to any power producer and charge them no more than what they pay for the use of their own lines. These rules set the stage for the retail sale of electricity to industrial, commercial and residential utility customers; non-utility generators (Nugs); and power marketers. These statutory, regulatory and administrative changes create for the electric utility industry two different forces that contradict each other. The first is the concept of competition among utility companies; this places a greater emphasis on electric power generation cost control and affects generation/fuel mix selection and demand side management (DSM) activities. The second force, which is converse to the first, is that utilities are major contributors to the air pollution burden in the United States and environmental concerns are forcing them to reduce emissions of air pollutants by using more environmentally friendly fuels and implementing energy saving programs. This study evaluates the impact of deregulation within the investor owned electric utilities and how this deregulation effects air quality by investigating the trend in demand side management programs and generation/fuel mix. A survey was conducted of investor owned utilities and independent power producers. The results of the survey were analyzed by analysis of variance and regression analysis to determine the impact to Air Pollution. An air Quality Impact model was also developed in this study. This model consists of six modules: (1) demand side management and (2) consumption of coal, (3) gas, (4) renewable, (5) oil and (6

  8. Isotope effect of mercury diffusion in air

    PubMed Central

    Koster van Groos, Paul G.; Esser, Bradley K.; Williams, Ross W.; Hunt, James R.

    2014-01-01

    Identifying and reducing impacts from mercury sources in the environment remains a considerable challenge and requires process based models to quantify mercury stocks and flows. The stable isotope composition of mercury in environmental samples can help address this challenge by serving as a tracer of specific sources and processes. Mercury isotope variations are small and result only from isotope fractionation during transport, equilibrium, and transformation processes. Because these processes occur in both industrial and environmental settings, knowledge of their associated isotope effects is required to interpret mercury isotope data. To improve the mechanistic modeling of mercury isotope effects during gas phase diffusion, an experimental program tested the applicability of kinetic gas theory. Gas-phase elemental mercury diffusion through small bore needles from finite sources demonstrated mass dependent diffusivities leading to isotope fractionation described by a Rayleigh distillation model. The measured relative atomic diffusivities among mercury isotopes in air are large and in agreement with kinetic gas theory. Mercury diffusion in air offers a reasonable explanation of recent field results reported in the literature. PMID:24364380

  9. Long-term Changes in Extreme Air Pollution Meteorology and the Implications for Air Quality.

    PubMed

    Hou, Pei; Wu, Shiliang

    2016-03-31

    Extreme air pollution meteorological events, such as heat waves, temperature inversions and atmospheric stagnation episodes, can significantly affect air quality. Based on observational data, we have analyzed the long-term evolution of extreme air pollution meteorology on the global scale and their potential impacts on air quality, especially the high pollution episodes. We have identified significant increasing trends for the occurrences of extreme air pollution meteorological events in the past six decades, especially over the continental regions. Statistical analysis combining air quality data and meteorological data further indicates strong sensitivities of air quality (including both average air pollutant concentrations and high pollution episodes) to extreme meteorological events. For example, we find that in the United States the probability of severe ozone pollution when there are heat waves could be up to seven times of the average probability during summertime, while temperature inversions in wintertime could enhance the probability of severe particulate matter pollution by more than a factor of two. We have also identified significant seasonal and spatial variations in the sensitivity of air quality to extreme air pollution meteorology.

  10. Long-term Changes in Extreme Air Pollution Meteorology and the Implications for Air Quality

    PubMed Central

    Hou, Pei; Wu, Shiliang

    2016-01-01

    Extreme air pollution meteorological events, such as heat waves, temperature inversions and atmospheric stagnation episodes, can significantly affect air quality. Based on observational data, we have analyzed the long-term evolution of extreme air pollution meteorology on the global scale and their potential impacts on air quality, especially the high pollution episodes. We have identified significant increasing trends for the occurrences of extreme air pollution meteorological events in the past six decades, especially over the continental regions. Statistical analysis combining air quality data and meteorological data further indicates strong sensitivities of air quality (including both average air pollutant concentrations and high pollution episodes) to extreme meteorological events. For example, we find that in the United States the probability of severe ozone pollution when there are heat waves could be up to seven times of the average probability during summertime, while temperature inversions in wintertime could enhance the probability of severe particulate matter pollution by more than a factor of two. We have also identified significant seasonal and spatial variations in the sensitivity of air quality to extreme air pollution meteorology. PMID:27029386

  11. Changes in the planetary heat balance with chemical changes in air

    NASA Technical Reports Server (NTRS)

    Chamberlain, J. W.

    1980-01-01

    The concept of an 'equivalent radiative atmosphere', a simplified model of the atmospheric radiative aspects, is used to explore changes in the greenhouse effect, caused by changes in the atmospheric composition, and changes in the incident solar flux. By extending this model to the zonal energy-balance type, it is shown that global heating has the more profound effect at higher latitudes. It is also shown that the positive feedback in H2O opacity is comparable to the initial change in opacity due, for example, to a change in CO2 content.

  12. Global premature mortality due to anthropogenic outdoor air pollution and the contribution of past climate change

    NASA Astrophysics Data System (ADS)

    Silva, Raquel A.; West, J. Jason; Zhang, Yuqiang; Anenberg, Susan C.; Lamarque, Jean-François; Shindell, Drew T.; Collins, William J.; Dalsoren, Stig; Faluvegi, Greg; Folberth, Gerd; Horowitz, Larry W.; Nagashima, Tatsuya; Naik, Vaishali; Rumbold, Steven; Skeie, Ragnhild; Sudo, Kengo; Takemura, Toshihiko; Bergmann, Daniel; Cameron-Smith, Philip; Cionni, Irene; Doherty, Ruth M.; Eyring, Veronika; Josse, Beatrice; MacKenzie, I. A.; Plummer, David; Righi, Mattia; Stevenson, David S.; Strode, Sarah; Szopa, Sophie; Zeng, Guang

    2013-09-01

    Increased concentrations of ozone and fine particulate matter (PM2.5) since preindustrial times reflect increased emissions, but also contributions of past climate change. Here we use modeled concentrations from an ensemble of chemistry-climate models to estimate the global burden of anthropogenic outdoor air pollution on present-day premature human mortality, and the component of that burden attributable to past climate change. Using simulated concentrations for 2000 and 1850 and concentration-response functions (CRFs), we estimate that, at present, 470 000 (95% confidence interval, 140 000 to 900 000) premature respiratory deaths are associated globally and annually with anthropogenic ozone, and 2.1 (1.3 to 3.0) million deaths with anthropogenic PM2.5-related cardiopulmonary diseases (93%) and lung cancer (7%). These estimates are smaller than ones from previous studies because we use modeled 1850 air pollution rather than a counterfactual low concentration, and because of different emissions. Uncertainty in CRFs contributes more to overall uncertainty than the spread of model results. Mortality attributed to the effects of past climate change on air quality is considerably smaller than the global burden: 1500 (-20 000 to 27 000) deaths yr-1 due to ozone and 2200 (-350 000 to 140 000) due to PM2.5. The small multi-model means are coincidental, as there are larger ranges of results for individual models, reflected in the large uncertainties, with some models suggesting that past climate change has reduced air pollution mortality.

  13. Health Effects of Climate Change

    MedlinePlus

    ... health. Climate defines health concerns such as the direct effects of excess heat or cold, the lack ... nih.gov/climatereport ) examined the state of the science on effects of climate change on human health. ...

  14. The effects of air pollution on children.

    PubMed

    Bates, D V

    1995-09-01

    Air pollutants have been documented to be associated with a wide variety of adverse health impacts in children. These include increases in mortality in very severe episodes; an increased risk of perineonatal mortality in regions of higher pollution, and an increased general rate of mortality in children; increased acute respiratory disease morbidity; aggravation of asthma, as shown by increased hospital emergency visits or admissions as well as in longitudinal panel studies; increased prevalence of respiratory symptoms in children, and infectious episodes of longer duration; lowered lung function in children when pollutants increase; lowered lung function in more polluted regions; increased sickness rates as indicated by kindergarten and school absences; the adverse effects of inhaled lead from automobile exhaust. These impacts are especially severe when high levels of outdoor pollution (usually from uncontrolled coal burning) are combined with high levels of indoor pollution. In developed countries, where indoor pollution levels are lower, increasing traffic density and elevated NO2 levels with secondary photochemical and fine particulate pollution appear to be the main contemporary problem. By virtue of physical activity out of doors when pollution levels may be high, children may experience higher exposures than adults. Air pollution is likely to have a greater impact on asthmatic children if they are without access to routine medical care.

  15. Quantifying the health impacts of air pollution under a changing climate-a review of approaches and methodology.

    PubMed

    Sujaritpong, Sarunya; Dear, Keith; Cope, Martin; Walsh, Sean; Kjellstrom, Tord

    2014-03-01

    Climate change has been predicted to affect future air quality, with inevitable consequences for health. Quantifying the health effects of air pollution under a changing climate is crucial to provide evidence for actions to safeguard future populations. In this paper, we review published methods for quantifying health impacts to identify optimal approaches and ways in which existing challenges facing this line of research can be addressed. Most studies have employed a simplified methodology, while only a few have reported sensitivity analyses to assess sources of uncertainty. The limited investigations that do exist suggest that examining the health risk estimates should particularly take into account the uncertainty associated with future air pollution emissions scenarios, concentration-response functions, and future population growth and age structures. Knowledge gaps identified for future research include future health impacts from extreme air pollution events, interactions between temperature and air pollution effects on public health under a changing climate, and how population adaptation and behavioural changes in a warmer climate may modify exposure to air pollution and health consequences.

  16. Effects of data selection on the assimilation of AIRS data

    NASA Technical Reports Server (NTRS)

    Joiner, Joanna; Brin, E.; Treadon, R.; Derber, J.; VanDelst, P.; DeSilva, A.; Marshall, J. Le; Poli, P.; Atlas, R.; Cruz, C.; Bungato, D.

    2006-01-01

    The Atmospheric InfraRed Sounder (AIRS), flying aboard NASA's Earth Observing System (EOS) Aqua satellite with the Advanced Microwave Sounding Unit-A (AMSU-A), has been providing data for use in numerical weather prediction (NWP) and data assimilation systems (DAS) for over three years. The full AIRS data set is currently not transmitted in near-real-time (NRT) to the NWP centers. Instead, data sets with reduced spatial and spectral information are produced and made available in NRT. In this paper, we evaluate the use of different channel selections and error specifications. We achieved significant positive impact from the Aqua AIRS/AMSU-A combination in both hemispheres during our experimental time period of January 2003. The best results were obtained using a set of 156 channels that did not include any in the 6.7micron water vapor band. The latter have a large influence on both temperature and humidity analyses. If observation and background errors are not properly specified, the partitioning of temperature and humidity information from these channels will not be correct, and this can lead to a degradation in forecast skill. We found that changing the specified channel errors had a significant effect on the amount of data that entered into the analysis as a result of quality control thresholds that are related to the errors. However, changing the channel errors within a relatively small window did not significantly impact forecast skill with the 155 channel set. We also examined the effects of different types of spatial data reduction on assimilated data sets and NWP forecast skill. Whether we picked the center or the warmest AIRS pixel in a 3x3 array affected the amount of data ingested by the analysis but had a negligible impact on the forecast skill.

  17. Effect of Intake Air Filter Condition on Vehicle Fuel Economy

    SciTech Connect

    Norman, Kevin M; Huff, Shean P; West, Brian H

    2009-02-01

    The U.S. Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy and the U.S. Environmental Protection Agency (EPA) jointly maintain a fuel economy website (www.fueleconomy.gov), which helps fulfill their responsibility under the Energy Policy Act of 1992 to provide accurate fuel economy information [in miles per gallon (mpg)] to consumers. The site provides information on EPA fuel economy ratings for passenger cars and light trucks from 1985 to the present and other relevant information related to energy use such as alternative fuels and driving and vehicle maintenance tips. In recent years, fluctuations in the price of crude oil and corresponding fluctuations in the price of gasoline and diesel fuels have renewed interest in vehicle fuel economy in the United States. (User sessions on the fuel economy website exceeded 20 million in 2008 compared to less than 5 million in 2004 and less than 1 million in 2001.) As a result of this renewed interest and the age of some of the references cited in the tips section of the website, DOE authorized the Oak Ridge National Laboratory (ORNL) Fuels, Engines, and Emissions Research Center (FEERC) to initiate studies to validate and improve these tips. This report documents a study aimed specifically at the effect of engine air filter condition on fuel economy. The goal of this study was to explore the effects of a clogged air filter on the fuel economy of vehicles operating over prescribed test cycles. Three newer vehicles (a 2007 Buick Lucerne, a 2006 Dodge Charger, and a 2003 Toyota Camry) and an older carbureted vehicle were tested. Results show that clogging the air filter has no significant effect on the fuel economy of the newer vehicles (all fuel injected with closed-loop control and one equipped with MDS). The engine control systems were able to maintain the desired AFR regardless of intake restrictions, and therefore fuel consumption was not increased. The carbureted engine did show a decrease in

  18. Examining Projected Changes in Weather & Air Quality Extremes Between 2000 & 2030 using Dynamical Downscaling

    EPA Science Inventory

    Climate change may alter regional weather extremes resulting in a range of environmental impacts including changes in air quality, water quality and availability, energy demands, agriculture, and ecology. Dynamical downscaling simulations were conducted with the Weather Research...

  19. Impacts of Changes of Indoor Air Pressure and Air Exchange Rate in Vapor Intrusion Scenarios.

    PubMed

    Shen, Rui; Suuberg, Eric M

    2016-02-01

    There has, in recent years, been increasing interest in understanding the transport processes of relevance in vapor intrusion of volatile organic compounds (VOCs) into buildings on contaminated sites. These studies have included fate and transport modeling. Most such models have simplified the prediction of indoor air contaminant vapor concentrations by employing a steady state assumption, which often results in difficulties in reconciling these results with field measurements. This paper focuses on two major factors that may be subject to significant transients in vapor intrusion situations, including the indoor air pressure and the air exchange rate in the subject building. A three-dimensional finite element model was employed with consideration of daily and seasonal variations in these factors. From the results, the variations of indoor air pressure and air exchange rate are seen to contribute to significant variations in indoor air contaminant vapor concentrations. Depending upon the assumptions regarding the variations in these parameters, the results are only sometimes consistent with the reports of several orders of magnitude in indoor air concentration variations from field studies. The results point to the need to examine more carefully the interplay of these factors in order to quantitatively understand the variations in potential indoor air exposures.

  20. Impacts of Changes of Indoor Air Pressure and Air Exchange Rate in Vapor Intrusion Scenarios

    PubMed Central

    Shen, Rui; Suuberg, Eric M.

    2016-01-01

    There has, in recent years, been increasing interest in understanding the transport processes of relevance in vapor intrusion of volatile organic compounds (VOCs) into buildings on contaminated sites. These studies have included fate and transport modeling. Most such models have simplified the prediction of indoor air contaminant vapor concentrations by employing a steady state assumption, which often results in difficulties in reconciling these results with field measurements. This paper focuses on two major factors that may be subject to significant transients in vapor intrusion situations, including the indoor air pressure and the air exchange rate in the subject building. A three-dimensional finite element model was employed with consideration of daily and seasonal variations in these factors. From the results, the variations of indoor air pressure and air exchange rate are seen to contribute to significant variations in indoor air contaminant vapor concentrations. Depending upon the assumptions regarding the variations in these parameters, the results are only sometimes consistent with the reports of several orders of magnitude in indoor air concentration variations from field studies. The results point to the need to examine more carefully the interplay of these factors in order to quantitatively understand the variations in potential indoor air exposures. PMID:28090133

  1. Analysis of Aircraft Evasion Strategies in Air-to-Air Missille Effectiveness Models

    DTIC Science & Technology

    1975-08-01

    AD-A015 238 ANALYSIS OF AIRCRAFT EVASION STRATEGIES IN AIR-TO-AIR MISSILE EFFECTIVENESS MObri ’ G. Carpenter, et al Grumman Aerospace Corporation ...overall tep t Es CIS*atiet d) Oft ’IsNA 1tTNG AC ?v I TV ? corpor te author) 2S. REPORT SECUNITY CLASSIrICA TION Unclassified ;rummn Aerospace... Corporation b RoU N/A I NEPOA’ I ?LE nalysis of Aircraft Evasion Strategies in Air-to-Air Missile Effectiveness Models 4 DESCRIP T IVE *40TS ’Type of repct

  2. What is an effective portable air cleaning device? A review.

    PubMed

    Shaughnessy, R J; Sextro, R G

    2006-04-01

    The use of portable air cleaning devices in residential settings has been steadily growing over the last 10 years. Three out of every 10 households now contain a portable air cleaning device. This increased use of air cleaners is accompanied by, if not influenced by, a fundamental belief by consumers that the air cleaners are providing an improved indoor air environment. However, there is a wide variation in the performance of air cleaners that is dependent on the specific air cleaner design and various indoor factors. The most widely used method in the United States to assess the performance of new air cleaners is the procedure described in the American National Standards Institute (ANSI)/Association of Home Appliance Manufacturers (AHAM) AC-1-2002. This method describes both the test conditions and the testing protocol. The protocol yields a performance metric that is based on the measured decay rate of contaminant concentrations with the air cleaner operating compared with the measured decay rate with the air cleaner turned off. The resulting metric, the clean air delivery rate (CADR), permits both an intercomparison of performance among various air cleaners and a comparison of air cleaner operation to other contaminant removal processes. In this article, we comment on the testing process, discuss its applicability to various contaminants, and evaluate the resulting performance metrics for effective air cleaning.

  3. Effect of Ambient Design Temperature on Air-Cooled Binary Plant Output

    SciTech Connect

    Dan Wendt; Greg Mines

    2011-10-01

    Air-cooled binary plants are designed to provide a specified level of power production at a particular air temperature. Nominally this air temperature is the annual mean or average air temperature for the plant location. This study investigates the effect that changing the design air temperature has on power generation for an air-cooled binary plant producing power from a resource with a declining production fluid temperature and fluctuating ambient temperatures. This analysis was performed for plants operating both with and without a geothermal fluid outlet temperature limit. Aspen Plus process simulation software was used to develop optimal air-cooled binary plant designs for specific ambient temperatures as well as to rate the performance of the plant designs at off-design operating conditions. Results include calculation of annual and plant lifetime power generation as well as evaluation of plant operating characteristics, such as improved power generation capabilities during summer months when electric power prices are at peak levels.

  4. Technology Solutions Case Study: Ventilation System Effectiveness and Tested Indoor Air Quality Impacts

    SciTech Connect

    A. Rudd and D. Bergey

    2015-08-01

    Ventilation system effectiveness testing was conducted at two unoccupied, single-family, detached lab homes at the University of Texas - Tyler. Five ventilation system tests were conducted with various whole-building ventilation systems. Multizone fan pressurization testing characterized building and zone enclosure leakage. PFT testing showed multizone air change rates and interzonal airflow filtration. Indoor air recirculation by a central air distribution system can help improve the exhaust ventilation system by way of air mixing and filtration. In contrast, the supply and balanced ventilation systems showed that there is a significant benefit to drawing outside air from a known outside location, and filtering and distributing that air. Compared to the Exhaust systems, the CFIS and ERV systems showed better ventilation air distribution and lower concentrations of particulates, formaldehyde and other VOCs.

  5. A new air quality perception scale for global assessment of air pollution health effects.

    PubMed

    Deguen, Séverine; Ségala, Claire; Pédrono, Gaëlle; Mesbah, Mounir

    2012-12-01

    Despite improvements in air quality in developed countries, air pollution remains a major public health issue. To fully assess the health impact, we must consider that air pollution exposure has both physical and psychological effects; this latter dimension, less documented, is more difficult to measure and subjective indicators constitute an appropriate alternative. In this context, this work presents the methodological development of a new scale to measure the perception of air quality, useful as an exposure or risk appraisal metric in public health contexts. On the basis of the responses from 2,522 subjects in eight French cities, psychometric methods are used to construct the scale from 22 items that assess risk perception (anxiety about health and quality of life) and the extent to which air pollution is a nuisance (sensorial perception and symptoms). The scale is robust, reproducible, and discriminates between subpopulations more susceptible to poor air pollution perception. The individual risk factors of poor air pollution perception are coherent with those findings in the risk perception literature. Perception of air pollution by the general public is a key issue in the development of comprehensive risk assessment studies as well as in air pollution risk management and policy. This study offers a useful new tool to measure such efforts and to help set priorities for air quality improvements in combination with air quality measurements.

  6. Changes in lung function after working with the shotcrete lining method under compressed air conditions.

    PubMed Central

    Kessel, R; Redl, M; Mauermayer, R; Praml, G J

    1989-01-01

    Shotcrete techniques under compressed air are increasingly applied in the construction of tunnels. Up to now little is known about the influence of shotcrete dusts on the function of the lung. The lung function of 30 miners working with shotcrete under compressed air (before and after one shift) was measured. They carried personal air samplers to assess the total dust exposure. Long term effects were studied on a second group of 29 individuals exposed to shotcrete dusts and compressed air for two years. A significant increase of airway resistance and a significant decrease of some flow-volume parameters were found after one workshift. These changes partially correlate close to the dust exposure. After two years exposure a significant decrease of mean expiratory flow (MEF)50 and MEF25 was found. These results point to damage in the small airways and emphasise the major role of the lung function test--including the flow-volume manoeuvre for the medical examination of the workers. Additionally, they should carry filter masks. Images PMID:2923823

  7. Changes in lung function after working with the shotcrete lining method under compressed air conditions.

    PubMed

    Kessel, R; Redl, M; Mauermayer, R; Praml, G J

    1989-02-01

    Shotcrete techniques under compressed air are increasingly applied in the construction of tunnels. Up to now little is known about the influence of shotcrete dusts on the function of the lung. The lung function of 30 miners working with shotcrete under compressed air (before and after one shift) was measured. They carried personal air samplers to assess the total dust exposure. Long term effects were studied on a second group of 29 individuals exposed to shotcrete dusts and compressed air for two years. A significant increase of airway resistance and a significant decrease of some flow-volume parameters were found after one workshift. These changes partially correlate close to the dust exposure. After two years exposure a significant decrease of mean expiratory flow (MEF)50 and MEF25 was found. These results point to damage in the small airways and emphasise the major role of the lung function test--including the flow-volume manoeuvre for the medical examination of the workers. Additionally, they should carry filter masks.

  8. Do sudden air temperature and pressure changes affect cardiovascular morbidity and mortality?

    NASA Astrophysics Data System (ADS)

    Plavcová, E.; Davídkovová, H.; Kyselý, J.

    2012-04-01

    Previous studies have shown that sudden changes in weather (usually represented by air temperature and/or pressure) are associated with increases in daily mortality. Little is understood about physiological mechanisms responsible for the impacts of weather changes on mortality, and whether similar patterns appear for morbidity as well. Relatively little is known also about differences in the magnitude of the mortality response in provincial regions and in cities, where the impacts may be exacerbated by air pollution effects and/or heat island. The present study examines the effects of sudden air temperature and pressure changes on morbidity (represented by hospital admissions) and mortality due to cardiovascular diseases in the population of the Czech Republic (approx. 10 million inhabitants) and separately in the city of Prague (1.2 million inhabitants). The events are selected from data covering 1994-2009 using the methodology introduced by Plavcová and Kyselý (2010), and they are compared with the datasets on hospital admissions and daily mortality (both standardized to account for long-term changes and the seasonal and weekly cycles). Relative deviations of morbidity/mortality from the baseline were averaged over the selected events for days D-2 (2 days before a change) up to D+7 (7 days after), and their statistical significance was tested by means of the Monte Carlo method. The study aims at (i) identifying those weather changes associated with increased cardiovascular morbidity/mortality, separately in summer and winter, (ii) comparing the effects of weather changes on morbidity and mortality, (iii) identifying whether urban population of Prague is more/less vulnerable in comparison to the population of the whole Czech Republic, (iv) comparing the effects for different cardiovascular diseases (ischaemic heart diseases, ICD-10 codes I20-I25; cerebrovascular diseases, I60-I69; hypertension, I10; atherosclerosis, I70) and individual population groups (by age

  9. Evaluation of co-benefits from combined climate change and air pollution reduction strategies

    NASA Astrophysics Data System (ADS)

    Leitao, Joana; Van Dingenen, Rita; Dentener, Frank; Rao, Shilpa

    2014-05-01

    climate and air pollution strategies assessed. The TM5-FASST tool allows for a fast screening of emission scenario variants and the resulting impacts can be investigated by source country, source sector level or by precursor. Developed at JRC, this model is a linearized version derived from the full chemical transport model TM5-CTM, taking as input pollutants emissions from 56 source regions with global coverage. The resulting pollutant concentrations are determined and their associated effect on human health (from PM2.5 and O3), the yield loss of damaged crops (from O3), and CO2eq of short lived climate forcers are quantified. The analysis of the LIMITS scenarios allows for impact assessment of alternate air pollution control assumptions on pollutant emission trajectories out to 2030 and 2050. The results show that stringent climate policies provide a significant air quality benefit compared to current legislation air quality policy. The identified benefits and trade-offs provide a strong incentive for the implementation of combined national policy focusing both on climate change and air pollution.

  10. Threat to future global food security from climate change and ozone air pollution

    NASA Astrophysics Data System (ADS)

    Tai, Amos P. K.; Martin, Maria Val; Heald, Colette L.

    2014-09-01

    Future food production is highly vulnerable to both climate change and air pollution with implications for global food security. Climate change adaptation and ozone regulation have been identified as important strategies to safeguard food production, but little is known about how climate and ozone pollution interact to affect agriculture, nor the relative effectiveness of these two strategies for different crops and regions. Here we present an integrated analysis of the individual and combined effects of 2000-2050 climate change and ozone trends on the production of four major crops (wheat, rice, maize and soybean) worldwide based on historical observations and model projections, specifically accounting for ozone-temperature co-variation. The projections exclude the effect of rising CO2, which has complex and potentially offsetting impacts on global food supply. We show that warming reduces global crop production by >10% by 2050 with a potential to substantially worsen global malnutrition in all scenarios considered. Ozone trends either exacerbate or offset a substantial fraction of climate impacts depending on the scenario, suggesting the importance of air quality management in agricultural planning. Furthermore, we find that depending on region some crops are primarily sensitive to either ozone (for example, wheat) or heat (for example, maize) alone, providing a measure of relative benefits of climate adaptation versus ozone regulation for food security in different regions.

  11. Effects on health of air pollution: a narrative review.

    PubMed

    Mannucci, Pier Mannuccio; Harari, Sergio; Martinelli, Ida; Franchini, Massimo

    2015-09-01

    Air pollution is a complex and ubiquitous mixture of pollutants including particulate matter, chemical substances and biological materials. There is growing awareness of the adverse effects on health of air pollution following both acute and chronic exposure, with a rapidly expanding body of evidence linking air pollution with an increased risk of respiratory (e.g., asthma, chronic obstructive pulmonary disease, lung cancer) and cardiovascular disease (e.g., myocardial infarction, heart failure, cerebrovascular accidents). Elderly subjects, pregnant women, infants and people with prior diseases appear especially susceptible to the deleterious effects of ambient air pollution. The main diseases associated with exposure to air pollutants will be summarized in this narrative review.

  12. Effects of temperature change on mussel, Mytilus.

    PubMed

    Zippay, Mackenzie L; Helmuth, Brian

    2012-09-01

    An increasing body of research has demonstrated the often idiosyncratic responses of organisms to climate-related factors, such as increases in air, sea and land surface temperatures, especially when coupled with non-climatic stressors. This argues that sweeping generalizations about the likely impacts of climate change on organisms and ecosystems are likely less valuable than process-based explorations that focus on key species and ecosystems. Mussels in the genus Mytilus have been studied for centuries, and much is known of their physiology and ecology. Like other intertidal organisms, these animals may serve as early indicators of climate change impacts. As structuring species, their survival has cascading impacts on many other species, making them ecologically important, in addition to their economic value as a food source. Here, we briefly review the categories of information available on the effects of temperature change on mussels within this genus. Although a considerable body of information exists about the genus in general, knowledge gaps still exist, specifically in our ability to predict how specific populations are likely to respond to the effects of multiple stressors, both climate and non-climate related, and how these changes are likely to result in ecosystem-level responses. Whereas this genus provides an excellent model for exploring the effects of climate change on natural and human-managed ecosystems, much work remains if we are to make predictions of likely impacts of environmental change on scales that are relevant to climate adaptation.

  13. Ambient air pollution, weather changes, and outpatient visits for allergic conjunctivitis: A retrospective registry study

    PubMed Central

    Hong, Jiaxu; Zhong, Taoling; Li, Huili; Xu, Jianming; Ye, Xiaofang; Mu, Zhe; Lu, Yi; Mashaghi, Alireza; Zhou, Ying; Tan, Mengxi; Li, Qiyuan; Sun, Xinghuai; Liu, Zuguo; Xu, Jianjiang

    2016-01-01

    Allergic conjunctivitis is a common problem that significantly impairs patients’ quality of life. Whether air pollution serves as a risk factor for the development of allergic conjunctivitis remains elusive. In this paper, we assess the relationship between air pollutants and weather conditions with outpatient visits for allergic conjunctivitis. By using a time-series analysis based on the largest dataset ever assembled to date, we found that the number of outpatient visits for allergic conjunctivitis was significantly correlated with the levels of NO2, O3, and temperature, while its association with humidity was statistically marginal. No associations between PM10, PM2.5, SO2, or wind velocity and outpatient visits were seen. Subgroup analyses showed that sex seemed to modify the effects of humidity on outpatient visits for allergic conjunctivitis, but not for NO2, O3, or temperature. People younger than 40 were found to be susceptible to changes of all four parameters, while those older than 40 were only consistently affected by NO2 levels. Our findings revealed that higher levels of ambient NO2, O3, and temperature increase the chances of outpatient visits for allergic conjunctivitis. Ambient air pollution and weather changes may contribute to the worsening of allergic conjunctivitis. PMID:27033635

  14. Ambient air pollution, weather changes, and outpatient visits for allergic conjunctivitis: A retrospective registry study.

    PubMed

    Hong, Jiaxu; Zhong, Taoling; Li, Huili; Xu, Jianming; Ye, Xiaofang; Mu, Zhe; Lu, Yi; Mashaghi, Alireza; Zhou, Ying; Tan, Mengxi; Li, Qiyuan; Sun, Xinghuai; Liu, Zuguo; Xu, Jianjiang

    2016-04-01

    Allergic conjunctivitis is a common problem that significantly impairs patients' quality of life. Whether air pollution serves as a risk factor for the development of allergic conjunctivitis remains elusive. In this paper, we assess the relationship between air pollutants and weather conditions with outpatient visits for allergic conjunctivitis. By using a time-series analysis based on the largest dataset ever assembled to date, we found that the number of outpatient visits for allergic conjunctivitis was significantly correlated with the levels of NO2, O3, and temperature, while its association with humidity was statistically marginal. No associations between PM10, PM2.5, SO2, or wind velocity and outpatient visits were seen. Subgroup analyses showed that sex seemed to modify the effects of humidity on outpatient visits for allergic conjunctivitis, but not for NO2, O3, or temperature. People younger than 40 were found to be susceptible to changes of all four parameters, while those older than 40 were only consistently affected by NO2 levels. Our findings revealed that higher levels of ambient NO2, O3, and temperature increase the chances of outpatient visits for allergic conjunctivitis. Ambient air pollution and weather changes may contribute to the worsening of allergic conjunctivitis.

  15. Ambient air pollution, weather changes, and outpatient visits for allergic conjunctivitis: A retrospective registry study

    NASA Astrophysics Data System (ADS)

    Hong, Jiaxu; Zhong, Taoling; Li, Huili; Xu, Jianming; Ye, Xiaofang; Mu, Zhe; Lu, Yi; Mashaghi, Alireza; Zhou, Ying; Tan, Mengxi; Li, Qiyuan; Sun, Xinghuai; Liu, Zuguo; Xu, Jianjiang

    2016-04-01

    Allergic conjunctivitis is a common problem that significantly impairs patients’ quality of life. Whether air pollution serves as a risk factor for the development of allergic conjunctivitis remains elusive. In this paper, we assess the relationship between air pollutants and weather conditions with outpatient visits for allergic conjunctivitis. By using a time-series analysis based on the largest dataset ever assembled to date, we found that the number of outpatient visits for allergic conjunctivitis was significantly correlated with the levels of NO2, O3, and temperature, while its association with humidity was statistically marginal. No associations between PM10, PM2.5, SO2, or wind velocity and outpatient visits were seen. Subgroup analyses showed that sex seemed to modify the effects of humidity on outpatient visits for allergic conjunctivitis, but not for NO2, O3, or temperature. People younger than 40 were found to be susceptible to changes of all four parameters, while those older than 40 were only consistently affected by NO2 levels. Our findings revealed that higher levels of ambient NO2, O3, and temperature increase the chances of outpatient visits for allergic conjunctivitis. Ambient air pollution and weather changes may contribute to the worsening of allergic conjunctivitis.

  16. Health effects of particulate air pollution: time for reassessment?

    PubMed Central

    Pope, C A; Bates, D V; Raizenne, M E

    1995-01-01

    Numerous studies have observed health effects of particulate air pollution. Compared to early studies that focused on severe air pollution episodes, recent studies are more relevant to understanding health effects of pollution at levels common to contemporary cities in the developed world. We review recent epidemiologic studies that evaluated health effects of particulate air pollution and conclude that respirable particulate air pollution is likely an important contributing factor to respiratory disease. Observed health effects include increased respiratory symptoms, decreased lung function, increased hospitalizations and other health care visits for respiratory and cardiovascular disease, increased respiratory morbidity as measured by absenteeism from work or school or other restrictions in activity, and increased cardiopulmonary disease mortality. These health effects are observed at levels common to many U.S. cities including levels below current U.S. National Ambient Air Quality Standards for particulate air pollution. Images Figure 1. PMID:7656877

  17. Comparative microarray analysis and pulmonary changes in Brown Norway rats exposed to ovalbumin and concentrated air particulates.

    PubMed

    Heidenfelder, Brooke L; Reif, David M; Harkema, Jack R; Cohen Hubal, Elaine A; Hudgens, Edward E; Bramble, Lori A; Wagner, James G; Morishita, Masako; Keeler, Gerald J; Edwards, Stephen W; Gallagher, Jane E

    2009-03-01

    The interaction between air particulates and genetic susceptibility has been implicated in the pathogenesis of asthma. The overall objective of this study was to determine the effects of inhalation exposure to environmentally relevant concentrated air particulates (CAPs) on the lungs of ovalbumin (ova) sensitized and challenged Brown Norway rats. Changes in gene expression were compared with lung tissue histopathology, morphometry, and biochemical and cellular parameters in bronchoalveolar lavage fluid (BALF). Ova challenge was responsible for the preponderance of gene expression changes, related largely to inflammation. CAPs exposure alone resulted in no significant gene expression changes, but CAPs and ova-exposed rodents exhibited an enhanced effect relative to ova alone with differentially expressed genes primarily related to inflammation and airway remodeling. Gene expression data was consistent with the biochemical and cellular analyses of the BALF, the pulmonary pathology, and morphometric changes when comparing the CAPs-ova group to the air-saline or CAPs-saline group. However, the gene expression data were more sensitive than the BALF cell type and number for assessing the effects of CAPs and ova versus the ova challenge alone. In addition, the gene expression results provided some additional insight into the TGF-beta-mediated molecular processes underlying these changes. The broad-based histopathology and functional genomic analyses demonstrate that exposure to CAPs exacerbates rodents with allergic inflammation induced by an allergen and suggests that asthmatics may be at increased risk for air pollution effects.

  18. Modeling exposure close to air pollution sources in naturally ventilated residences: association of turbulent diffusion coefficient with air change rate.

    PubMed

    Cheng, Kai-Chung; Acevedo-Bolton, Viviana; Jiang, Ruo-Ting; Klepeis, Neil E; Ott, Wayne R; Fringer, Oliver B; Hildemann, Lynn M

    2011-05-01

    For modeling exposure close to an indoor air pollution source, an isotropic turbulent diffusion coefficient is used to represent the average spread of emissions. However, its magnitude indoors has been difficult to assess experimentally due to limitations in the number of monitors available. We used 30-37 real-time monitors to simultaneously measure CO at different angles and distances from a continuous indoor point source. For 11 experiments involving two houses, with natural ventilation conditions ranging from <0.2 to >5 air changes per h, an eddy diffusion model was used to estimate the turbulent diffusion coefficients, which ranged from 0.001 to 0.013 m² s⁻¹. The model reproduced observed concentrations with reasonable accuracy over radial distances of 0.25-5.0 m. The air change rate, as measured using a SF₆ tracer gas release, showed a significant positive linear correlation with the air mixing rate, defined as the turbulent diffusion coefficient divided by a squared length scale representing the room size. The ability to estimate the indoor turbulent diffusion coefficient using two readily measurable parameters (air change rate and room dimensions) is useful for accurately modeling exposures in close proximity to an indoor pollution source.

  19. Effectiveness of in-room air filtration and dilution ventilation for tuberculosis infection control

    SciTech Connect

    Miller-Leiden, S.; Lobascio, C.; Nazaroff, W.W.; Macher, J.M.

    1996-09-01

    Tuberculosis (TB) is a public health problem that may pose substantial risks to health care workers and others. TB infection occurs by inhalation of airborne bacteria emitted by persons with active disease. We experimentally evaluated the effectiveness of in-room air filtration systems, specifically portable air filters (PAFs) and ceiling-mounted air filters (CMAFs), in conjunction with dilution ventilation, for controlling TB exposure in high-risk settings. For each experiment, a test aerosol was continuously generated and released into a full-sized room. With the in-room air filter and room ventilation system operating, time-averaged airborne particle concentrations were measured at several points. The effectiveness of in-room air filtration plus ventilation was determined by comparing particle concentrations with and without device operation. The four PAFs and three CMAFs we evaluated reduced room-average particle concentrations, typically by 30% to 90%, relative to a baseline scenario with two air-changes per hour of ventilation (outside air) only. Increasing the rate of air flow recirculating through the filter and/or air flow from the ventilation did not always increase effectiveness. Concentrations were generally higher near the emission source than elsewhere in the room. Both the air flow configuration of the filter and its placement within the room were important. 46 refs., 12 figs., 1 tab.

  20. Air plasma effect on dental disinfection

    SciTech Connect

    Duarte, S.; Murata, R. M.; Saxena, D.; Kuo, S. P.; Chen, C. Y.; Huang, K. J.; Popovic, S.

    2011-07-15

    A nonthermal low temperature air plasma jet is characterized and applied to study the plasma effects on oral pathogens and biofilms. Experiments were performed on samples of six defined microorganisms' cultures, including those of gram-positive bacteria and fungi, and on a cultivating biofilm sample of Streptococcus mutans UA159. The results show that the plasma jet creates a zone of microbial growth inhibition in each treated sample; the zone increases with the plasma treatment time and expands beyond the entire region directly exposed to the plasma jet. With 30s plasma treatment twice daily during 5 days of biofilm cultivation, its formation was inhibited. The viability of S. mutans cells in the treated biofilms dropped to below the measurable level and the killed bacterial cells concentrated to local regions as manifested by the fluorescence microscopy via the environmental scanning electron microscope. The emission spectroscopy of the jet indicates that its plasma effluent carries an abundance of reactive atomic oxygen, providing catalyst for the observed plasma effect.

  1. Air plasma effect on dental disinfection

    NASA Astrophysics Data System (ADS)

    Duarte, S.; Kuo, S. P.; Murata, R. M.; Chen, C. Y.; Saxena, D.; Huang, K. J.; Popovic, S.

    2011-07-01

    A nonthermal low temperature air plasma jet is characterized and applied to study the plasma effects on oral pathogens and biofilms. Experiments were performed on samples of six defined microorganisms' cultures, including those of gram-positive bacteria and fungi, and on a cultivating biofilm sample of Streptococcus mutans UA159. The results show that the plasma jet creates a zone of microbial growth inhibition in each treated sample; the zone increases with the plasma treatment time and expands beyond the entire region directly exposed to the plasma jet. With 30s plasma treatment twice daily during 5 days of biofilm cultivation, its formation was inhibited. The viability of S. mutans cells in the treated biofilms dropped to below the measurable level and the killed bacterial cells concentrated to local regions as manifested by the fluorescence microscopy via the environmental scanning electron microscope. The emission spectroscopy of the jet indicates that its plasma effluent carries an abundance of reactive atomic oxygen, providing catalyst for the observed plasma effect.

  2. Effect of air on water capillary flow in silica nanochannels

    NASA Astrophysics Data System (ADS)

    Zambrano, Harvey; Walther, Jens; Oyarzua, Elton

    2013-11-01

    Capillarity is a classical topic in fluid dynamics. The fundamental relationship between capillarity and surface tension is solidly established. Nevertheless, capillarity is an active research area especially as the miniaturization of devices is reaching the molecular scale. Currently, with the fabrication of microsystems integrated by nanochannels, a thorough understanding of the transport of fluids in nanoconfinement is required for a successful operation of the functional parts of such devices. In this work, Molecular Dynamics simulations are conducted to study the spontaneous imbibition of water in sub 10 nm silica channels. The capillary filling speed is computed in channels subjected to different air pressures. In order to describe the interactions between the species, an effective force field is developed, which is calibrated by reproducing the water contact angle. The results show that the capillary filling speed qualitatively follows the classical Washburn model, however, quantitatively it is lower than expected. Furthermore, it is observed that the deviations increase as air pressure is higher. We attribute the deviations to amounts of air trapped at the silica-water interface which leads to changes in the dynamics contact angle of the water meniscus.

  3. The impact of changing technology on the demand for air transportation

    NASA Technical Reports Server (NTRS)

    Kneafsey, J. T.; Taneja, N. K.

    1978-01-01

    Demand models for air transportation that are sensitive to the impact of changing technology were developed. The models are responsive to potential changes in technology, and to changing economic, social, and political factors as well. In addition to anticipating the wide differences in the factors influencing the demand for long haul and short haul air travel, the models were designed to clearly distinguish among the unique features of these markets.

  4. Characterization of air freshener emission: the potential health effects.

    PubMed

    Kim, Sanghwa; Hong, Seong-Ho; Bong, Choon-Keun; Cho, Myung-Haing

    2015-01-01

    Air freshener could be one of the multiple sources that release volatile organic compounds (VOCs) into the indoor environment. The use of these products may be associated with an increase in the measured level of terpene, such as xylene and other volatile air freshener components, including aldehydes, and esters. Air freshener is usually used indoors, and thus some compounds emitted from air freshener may have potentially harmful health impacts, including sensory irritation, respiratory symptoms, and dysfunction of the lungs. The constituents of air fresheners can react with ozone to produce secondary pollutants such as formaldehyde, secondary organic aerosol (SOA), oxidative product, and ultrafine particles. These pollutants then adversely affect human health, in many ways such as damage to the central nervous system, alteration of hormone levels, etc. In particular, the ultrafine particles may induce severe adverse effects on diverse organs, including the pulmonary and cardiovascular systems. Although the indoor use of air freshener is increasing, deleterious effects do not manifest for many years, making it difficult to identify air freshener-associated symptoms. In addition, risk assessment recognizes the association between air fresheners and adverse health effects, but the distinct causal relationship remains unclear. In this review, the emitted components of air freshener, including benzene, phthalate, and limonene, were described. Moreover, we focused on the health effects of these chemicals and secondary pollutants formed by the reaction with ozone. In conclusion, scientific guidelines on emission and exposure as well as risk characterization of air freshener need to be established.

  5. Measurements of CFC Isotope Changes in Firn, Stratospheric and Tropospheric Air

    NASA Astrophysics Data System (ADS)

    Allin, S.; Laube, J.; Witrant, E.; Kaiser, J.; McKenna, E.; Dennis, P.; Mulvaney, R.; Capron, E.; Martinerie, P.; Blunier, T.; Schwander, J.; Fraser, P. J.; Sturges, W. T.

    2014-12-01

    The degradation of chlorofluorocarbons (CFCs) releases chlorine, which is a major contributor to the destruction of stratospheric ozone. Recent studies of CFC-12 (CCl2F2) have reported strong chlorine and carbon isotope fractionations in stratospheric and tropospheric samples, respectively. The δ(37Cl) variations were attributed to isotope dependent sink reactions, similar to effects seen in nitrous oxide (N2O), whereas adjustments to manufacturing processes were used to explain the δ(13C) changes. Using air archives to measure chlorine and carbon isotope ratios in CFCs could help to identify and quantify their sources and sinks. We analyse the three most abundant CFCs and show that CFC-11 (CCl3F) and CFC-113 (CClF2CCl2F) exhibit significant chlorine isotope fractionation in the stratosphere, in common with CFC-12. We then use a 2-box model to estimate the expected tropospheric isotope signature of these gases, based on their emissions and transport history, as well as their measured stratospheric isotope fractionation constants (ɛapp). We also present long-term δ(37Cl) and δ(13C) trends of all three CFCs, determined from background tropospheric samples from the Cape Grim air archive (1978 - 2010) and firn air samples from the Arctic (NEEM, Greenland) and Antarctica (Fletcher Promontory). These measurements are compared to our model trends, leading to an evaluation of long-term chlorine and carbon isotope changes. This study also extends the novel approach to measuring trace gas isotope ratios in small air volumes, using a single-detector gas chromatography-mass spectrometry system.

  6. Policy Implications of Air Quality Research and Co-benefit to Climate Change

    NASA Astrophysics Data System (ADS)

    Fernandez, A.

    2007-05-01

    In recent decades air pollution has become one of the most important problems of megacities and large urban centers. Photochemical smog induced from motorization, industrial activities, power generation, and solvents, has now become the main source of concern for air quality. Air pollution has serious impacts on public health and ecosystems, causes urban and regional haze, and has the potential to contribute significantly to climate change. While an integrated approach is required to address air pollution problems to achieve and sustain improvements, policy strategies must be based on a solid understanding of the pollutant emissions and atmospheric processes that lead to unacceptable levels of air quality. This talk will address the air pollution problems in the Mexico City Metropolitan Area and other large urban centers in Mexico, and the strategies undertaken by the Mexican authorities to improve air quality and reduce greenhouse gas emissions.

  7. Climate change and river temperature sensitivity to warmer nighttime vs. warmer daytime air temperatures

    NASA Astrophysics Data System (ADS)

    Diabat, M.; Haggerty, R.; Wondzell, S. M.

    2011-12-01

    We investigated the July river temperature response to atmospheric warming over the diurnal cycle in a 36 km reach of the upper Middle Fork John Day River of Oregon, USA. The physical model Heat Source was calibrated and used to run 3 different cases of increased air temperature during July: 1) uniform increase over the whole day ("delta method"), 2) warmer daytime, and 3) warmer nighttime. All 3 cases had the same mean daily air temperatures - a 4 °C increase relative to 2002. Results show that the timing of air temperature increases has a significant effect on the magnitude, timing and duration of changes in water temperatures relative to current conditions. In all cases, river temperatures in the lower reach increased by at least 1.1 °C . For the delta case, water temperature increases never exceeded 2.3 °C. In contrast, under the warmer daytime case, water temperature increases exceeded 2.3 °C for 6.6 hours/day on average, with the largest increases occurring during mid-day. In the warmer night case the river temperature increases exceeded 2.3 °C for 4.3 hours/day on average with the largest increases occurring around midnight. In addition, an average increase of 4 °C in air temperature under the delta case increased the water temperature by an average of 1.9 °C uniformly during daytime and nighttime. Still, an average increase of 4 °C in air temperature under the warmer daytime case increased water temperature by an average of at least 1.6 °C during the daytime and by an average of up to 2.5 °C during the nighttime, while an average increase of 4 °C in air temperature under the warmer nighttime case increased the water temperature by an average of at least 1.4 °C during the nighttime and by an average of up to 2.4 °C during the daytime. The spatial response of temperature was different for each case. The lower 13 rkm warmed by at least 1.1 °C with the delta case, while only the lower 6 rkm warmed by at least 1.1 °C with the warmer daytime case

  8. UNDERSTANDING THE EFFECTS OF AIR POLLUTION ON HUMAN HEALTH

    EPA Science Inventory

    Modern air pollution regulation is first and foremost motivated by concerns about the effects of air pollutants on human health and secondarily by concerns about its effects on ecosystems, cultural artifacts, and quality of life values such as visibility. This order of priority ...

  9. A determination of character and frequency changes in air masses using a spatial synoptic classification

    NASA Astrophysics Data System (ADS)

    Kalkstein, Laurence S.; Sheridan, Scott C.; Graybeal, Daniel Y.

    1998-09-01

    Of the numerous climate change studies which have been performed, few of these have analyzed recent trends using an air mass-based approach. The air mass approach is superior to simple trend analysis, as it can identify patterns which may be too subtle to influence the entire climate record. The recently-developed spatial synoptic classification (SSC) is thus used to identify trends over the contiguous United States for summer and winter seasons from 1948 to 1993. Both trends in air mass frequency and character have been assessed.The most noteworthy trend in frequency is a decline in air mass transitional days (TR) during both seasons. In winter, decreases of up to 1% per decade are noted in parts of the central U.S. Other notable trends include a decrease in moist tropical (MT) air in winter, and an increase in MT in summer over the southeastern states.Numerous national and local air mass character changes have been uncovered. A large overall upward trend in cloudiness is noted in summer. All air masses feature an overnight increase, yet afternoon cloudiness increases are generally limited to the three dry air masses. Also in summer, a significant warming and increase in dew point of MT air has occurred at many locales. The most profound winter trend is a large decrease in dew point (up to 1.5°C per decade) in the dry polar (DP) air mass over much of the eastern states.

  10. Technological change and productivity growth in the air transport industry

    NASA Technical Reports Server (NTRS)

    Rosenberg, N.; Thompson, A.; Belsley, S. E.

    1978-01-01

    The progress of the civil air transport industry in the United States was examined in the light of a proposal of Enos who, after examining the growth of the petroleum industry, divided that phenomenon into two phases, the alpha and the beta; that is, the invention, first development and production, and the improvement phase. The civil air transport industry developed along similar lines with the technological progress coming in waves; each wave encompassing several new technological advances while retaining the best of the old ones. At the same time the productivity of the transport aircraft as expressed by the product of the aircraft velocity and the passenger capacity increased sufficiently to allow the direct operating cost in cents per passenger mile to continually decrease with each successive aircraft development.

  11. Guide for Air Force Change of Command Ceremonies

    DTIC Science & Technology

    1986-04-01

    May of 1982 he became the Aide -de-Camp to the Air Logistics Center Commander. He held that position until January 1984 when he became the Deputy...Combat Logistics Support Squadron. He was promoted to the grade of major in December 1983. As the Aide -de-Camp, Major Easterly participated in the...Establish dates and required participants.) 17. MUSIC (banI or taped) - 13. INCLEMENT WEATHER PLAN 19. MEDIA SUPPORT 20. PHOTOGRAPHIC COVERAGE ?1. RECEPTION

  12. Comprehensive national database of tree effects on air quality and human health in the United States.

    PubMed

    Hirabayashi, Satoshi; Nowak, David J

    2016-08-01

    Trees remove air pollutants through dry deposition processes depending upon forest structure, meteorology, and air quality that vary across space and time. Employing nationally available forest, weather, air pollution and human population data for 2010, computer simulations were performed for deciduous and evergreen trees with varying leaf area index for rural and urban areas in every county in the conterminous United States. The results populated a national database of annual air pollutant removal, concentration changes, and reductions in adverse health incidences and costs for NO2, O3, PM2.5 and SO2. The developed database enabled a first order approximation of air quality and associated human health benefits provided by trees with any forest configurations anywhere in the conterminous United States over time. Comprehensive national database of tree effects on air quality and human health in the United States was developed.

  13. Footprints of air pollution and changing environment on the sustainability of built infrastructure.

    PubMed

    Kumar, Prashant; Imam, Boulent

    2013-02-01

    Over 150 research articles relating three multi-disciplinary topics (air pollution, climate change and civil engineering structures) are reviewed to examine the footprints of air pollution and changing environment on the sustainability of building and transport structures (referred as built infrastructure). The aim of this review is to synthesize the existing knowledge on this topic, highlight recent advances in our understanding and discuss research priorities. The article begins with the background information on sources and emission trends of global warming (CO(2), CH(4), N(2)O, CFCs, SF(6)) and corrosive (SO(2), O(3), NO(X)) gases and their role in deterioration of building materials (e.g. steel, stone, concrete, brick and wood) exposed in outdoor environments. Further section covers the impacts of climate- and pollution-derived chemical pathways, generally represented by dose-response functions (DRFs), and changing environmental conditions on built infrastructure. The article concludes with the discussions on the topic areas covered and research challenges. A comprehensive inventory of DRFs is compiled. The case study carried out for analysing the inter-comparability of various DRFs on four different materials (carbon steel, limestone, zinc and copper) produced comparable results. Results of another case study revealed that future projected changes in temperature and/or relatively humidity are expected to have a modest effect on the material deterioration rate whereas changes in precipitation were found to show a more dominant impact. Evidences suggest that both changing and extreme environmental conditions are expected to affect the integrity of built infrastructure both in terms of direct structural damage and indirect losses of transport network functionality. Unlike stone and metals, substantially limited information is available on the deterioration of brick, concrete and wooden structures. Further research is warranted to develop more robust and

  14. Cooling of Gas Turbines I - Effects of Addition of Fins to Blade Tips and Rotor, Admission of Cooling Air Through Part of Nozzles, and Change in Thermal Conductivity of Turbine Components

    NASA Technical Reports Server (NTRS)

    Brown, Byron

    1947-01-01

    An analysis was developed for calculating the radial temperature distribution in a gas turbine with only the temperatures of the gas and the cooling air and the surface heat-transfer coefficient known. This analysis was applied to determine the temperatures of a complete wheel of a conventional single-stage impulse exhaust-gas turbine. The temperatures were first calculated for the case of the turbine operating at design conditions of speed, gas flow, etc. and with only the customary cooling arising from exposure of the outer blade flange and one face of the rotor to the air. Calculations were next made for the case of fins applied to the outer blade flange and the rotor. Finally the effects of using part of the nozzles (from 0 to 40 percent) for supplying cooling air and the effects of varying the metal thermal conductivity from 12 to 260 Btu per hour per foot per degree Farenheit on the wheel temperatures were determined. The gas temperatures at the nozzle box used in the calculations ranged from 1600F to 2000F. The results showed that if more than a few hundred degrees of cooling of turbine blades are required other means than indirect cooling with fins on the rotor and outer blade flange would be necessary. The amount of cooling indicated for the type of finning used could produce some improvement in efficiency and a large increase in durability of the wheel. The results also showed that if a large difference is to exist between the effective temperature of the exhaust gas and that of the blade material, as must be the case with present turbine materials and the high exhaust-gas temperatures desired (2000F and above), two alternatives are suggested: (a) If metal with a thermal conductivity comparable with copper is used, then the blade temperature can be reduced by strong cooling at both the blade tip and root. The center of the blade will be less than 2000F hotter than the ends; (b) With low conductivity materials some method of direct cooling other than

  15. [Aerodynamics study on pressure changes inside pressure-type whole-body plethysmograph produced by flowing air].

    PubMed

    Xu, Wei-Hua; Shen, Hua-Hao

    2010-02-25

    When using pressure-type plethysmography to test lung function of rodents, calculation of lung volume is always based on Boyle's law. The precondition of Boyle's law is that perfect air is static. However, air in the chamber is flowing continuously when a rodent breathes inside the chamber. Therefore, Boyle's law, a principle of air statics, may not be appropriate for measuring pressure changes of flowing air. In this study, we deduced equations for pressure changes inside pressure-type plethysmograph and then designed three experiments to testify the theoretic deduction. The results of theoretic deduction indicated that increased pressure was generated from two sources: one was based on Boyle's law, and the other was based on the law of conservation of momentum. In the first experiment, after injecting 0.1 mL, 0.2 mL, 0.4 mL of air into the plethysmograph, the pressure inside the chamber increased sharply to a peak value, then promptly decreased to horizontal pressure. Peak values were significantly higher than the horizontal values (P<0.001). This observation revealed that flowing air made an extra effect on air pressure in the plethysmograph. In the second experiment, the same volume of air was injected into the plethysmograph at different frequencies (0, 0.5, 1, 2, 3 Hz) and pressure changes inside were measured. The results showed that, with increasing frequencies, the pressure changes in the chamber became significantly higher (P<0.001). In the third experiment, small animal ventilator and pipette were used to make two types of airflow with different functions of time. The pressure changes produced by the ventilator were significantly greater than those produced by the pipette (P<0.001). Based on the data obtained, we draw the conclusion that, the flow of air plays a role in pressure changes inside the plethysmograph, and the faster the airflow is, the higher the pressure changes reach. Furthermore, the type of airflow also influences the pressure changes.

  16. Coal mining activities change plant community structure due to air pollution and soil degradation.

    PubMed

    Pandey, Bhanu; Agrawal, Madhoolika; Singh, Siddharth

    2014-10-01

    The aim of this study was to investigate the effects of coal mining activities on the community structures of woody and herbaceous plants. The response of individual plants of community to defilement caused by coal mining was also assessed. Air monitoring, soil physico-chemical and phytosociological analyses were carried around Jharia coalfield (JCF) and Raniganj coalfield. The importance value index of sensitive species minified and those of tolerant species enhanced with increasing pollution load and altered soil quality around coal mining areas. Although the species richness of woody and herbaceous plants decreased with higher pollution load, a large number of species acclimatized to the stress caused by the coal mining activities. Woody plant community at JCF was more affected by coal mining than herbaceous community. Canonical correspondence analysis revealed that structure of herbaceous community was mainly driven by soil total organic carbon, soil nitrogen, whereas woody layer community was influenced by sulphur dioxide in ambient air, soil sulphate and soil phosphorus. The changes in species diversity observed at mining areas indicated an increase in the proportion of resistant herbs and grasses showing a tendency towards a definite selection strategy of ecosystem in response to air pollution and altered soil characteristics.

  17. Contribution of ecosystem services to air quality and climate change mitigation policies: the case of urban forests in Barcelona, Spain.

    PubMed

    Baró, Francesc; Chaparro, Lydia; Gómez-Baggethun, Erik; Langemeyer, Johannes; Nowak, David J; Terradas, Jaume

    2014-05-01

    Mounting research highlights the contribution of ecosystem services provided by urban forests to quality of life in cities, yet these services are rarely explicitly considered in environmental policy targets. We quantify regulating services provided by urban forests and evaluate their contribution to comply with policy targets of air quality and climate change mitigation in the municipality of Barcelona, Spain. We apply the i-Tree Eco model to quantify in biophysical and monetary terms the ecosystem services "air purification," "global climate regulation," and the ecosystem disservice "air pollution" associated with biogenic emissions. Our results show that the contribution of urban forests regulating services to abate pollution is substantial in absolute terms, yet modest when compared to overall city levels of air pollution and GHG emissions. We conclude that in order to be effective, green infrastructure-based efforts to offset urban pollution at the municipal level have to be coordinated with territorial policies at broader spatial scales.

  18. Behavioural change, indoor air pollution and child respiratory health in developing countries: a review.

    PubMed

    Barnes, Brendon R

    2014-04-25

    Indoor air pollution caused by the indoor burning of solid biomass fuels has been associated with Acute Respiratory Infections such as pneumonia amongst children of less than five years of age. Behavioural change interventions have been identified as a potential strategy to reduce child indoor air pollution exposure, yet very little is known about the impact of behavioural change interventions to reduce indoor air pollution. Even less is known about how behaviour change theory has been incorporated into indoor air pollution behaviour change interventions. A review of published studies spanning 1983-2013 suggests that behavioural change strategies have the potential to reduce indoor air pollution exposure by 20%-98% in laboratory settings and 31%-94% in field settings. However, the evidence is: (1) based on studies that are methodologically weak; and (2) have little or no underlying theory. The paper concludes with a call for more rigorous studies to evaluate the role of behavioural change strategies (with or without improved technologies) to reduce indoor air pollution exposure in developing countries as well as interventions that draw more strongly on existing behavioural change theory and practice.

  19. Changes in young's modulus and electrical conductivity of nuclear grade graphites oxidized with air

    NASA Astrophysics Data System (ADS)

    Imai, Hisashi; Fujii, Kimio; Kurosawa, Takeshi; Nomura, Shinzo

    1983-10-01

    Five kinds of nuclear grade graphites were oxidized to study thermal oxidation effects on Young's modulus and electrical conductivity. The property changes were measured on specimens which were oxidized uniformly throughout their whole volume in the temperature range 500-600°C in air. The following relations were derived as a function of the bulk density of the graphites: E/ E0 = ( ρ/ ρ0) nE and R0/ R = ( ρ/ ρ0) nR, where E, R and ρ are Young's modulus, specific electrical resistivity and bulk density, respectively, and subscript zero refers to the initial unoxidized condition. The exponents nE and nR were found to be dependent on both the kind of graphite and the oxidation temperature, and the dependences were discussed in connection with selective oxidation in the graphite texture. It was also tried to relate the property changes with oxidation rate.

  20. Effective strategies for behavior change.

    PubMed

    Coleman, Mary Thoesen; Pasternak, Ryan H

    2012-06-01

    Strategies that are most effective in both prevention and management of chronic disease consider factors such as age, ethnicity, community, and technology. Most behavioral change strategies derive their components from application of the health belief model, the theory of reasoned action/theory of planned behavior, transtheoretical model, and social cognitive theory. Many tools such as the readiness ruler and personalized action plan form are available to assist health care teams to facilitate healthy behavior change. Primary care providers can support behavior changes by providing venues for peer interventions and family meetings and by making new partnerships with community organizations.

  1. Rapid microRNA changes in airways of human volunteers after controlled exposure to air pollutants

    EPA Science Inventory

    Introduction/Rationale: Exposure to air pollutants, including ozone and diesel exhaust (DE) are known to cause acute cardiopulmonary dysfunction; however, the molecular mechanisms underlying these changes remain elusive. One mechanism for rapid regulation of multiple genes is a...

  2. EPA Provides $8.5 Million to Protect Air Quality in a Changing Climate

    EPA Pesticide Factsheets

    WASHINGTON - Today, the U.S. Environmental Protection Agency (EPA) announced $8.5 million in research funding to 12 universities to protect air quality from the current and future challenges associated with the impacts of climate change.

  3. Concrete blocks` adverse effects on indoor air and recommended solutions

    SciTech Connect

    Ruppersberger, J.S.

    1995-04-01

    Air infiltration through highly permeable concrete blocks can allow entry of various serious indoor air pollutants including radon. An easy approach to avoiding these pollutants is to select a less-air-permeable concrete block. Tests show that air permeability of concrete blocks can vary by a factor greater than 50 (0.63--35 standard L/min/m{sup 2} at 3 Pa). The surface texture of the blocks correlates well with air permeability; test results of smoother, closed-surface-texture blocks were usually less air-permeable. During construction, air infiltration can be minimized by capping walls and carefully sealing around openings for utilities or other penetrations. Structures with indoor air-quality problems due to soil-gas entry can be mitigated more effectively with less coating material if the blocks have a closed surface texture. All coatings evaluated--cementaceous block filler (which has the lowest applied cost and is more than 99.5% effective), surface bonding cement, water-based epoxy, polysulfide vinyl acrylic, and latex (three coats)--were highly effective (more than 98%) in reducing air permeability when adequately applied. Coating selection should be influenced by expected service life, considering surface condition and cost.

  4. Tackling air pollution and extreme climate changes in China: Implementing the Paris climate change agreement.

    PubMed

    Tambo, Ernest; Duo-Quan, Wang; Zhou, Xiao-Nong

    2016-10-01

    China still depends on coal for more than 60% of its power despite big investments in the process of shifting to nuclear, solar and wind power renewable energy resources alignment with Paris climate change agreement (Paris CCA). Chinese government through the Communist Party Central Committee (CPCC) ascribes great importance and commitment to Paris CCA legacy and history landmark implementation at all levels. As the world's biggest carbon dioxide emitter, China has embarked on "SMART" pollution and climate changes programs and measures to reduce coal-fired power plants to less than 50% in the next five years include: new China model of energy policies commitment on CO2 and greenhouse gas emissions reductions to less than 20% non-fossil energy use by 2030 without undermining their economic growth, newly introduced electric vehicles transportation benefits, interactive and sustained air quality index (AQI) monitoring systems, decreasing reliance on fossil fuel economic activities, revision of energy price reforms and renewable energy to less energy efficient technologies development. Furthermore, ongoing CPCC improved environmental initiatives, implemented strict regulations and penalties on local companies and firms' pollution production management, massive infrastructures such as highways to reduce CO2 expansion of seven regional emissions trading markets and programs for CO2 emissions and other pollutants are being documented. Maximizing on the centralized nature of the China's government, implemented Chinese pollution, climate changes mitigation and adaptation initiatives, "SMART" strategies and credible measures are promising. A good and practical example is the interactive and dynamic website and database covering 367 Chinese cities and providing real time information on environmental and pollution emissions AQI. Also, water quality index (WQI), radiation and nuclear safety monitoring and management systems over time and space. These are ongoing Chinese

  5. Changes in tropospheric composition and air quality due to stratospheric ozone depletion and climate change.

    PubMed

    Wilson, S R; Solomon, K R; Tang, X

    2007-03-01

    It is well-understood that reductions in air quality play a significant role in both environmental and human health. Interactions between ozone depletion and global climate change will significantly alter atmospheric chemistry which, in turn, will cause changes in concentrations of natural and human-made gases and aerosols. Models predict that tropospheric ozone near the surface will increase globally by up to 10 to 30 ppbv (33 to 100% increase) during the period 2000 to 2100. With the increase in the amount of the stratospheric ozone, increased transport from the stratosphere to the troposphere will result in different responses in polluted and unpolluted areas. In contrast, global changes in tropospheric hydroxyl radical (OH) are not predicted to be large, except where influenced by the presence of oxidizable organic matter, such as from large-scale forest fires. Recent measurements in a relatively clean location over 5 years showed that OH concentrations can be predicted by the intensity of solar ultraviolet radiation. If this relationship is confirmed by further observations, this approach could be used to simplify assessments of air quality. Analysis of surface-level ozone observations in Antarctica suggests that there has been a significant change in the chemistry of the boundary layer of the atmosphere in this region as a result of stratospheric ozone depletion. The oxidation potential of the Antarctic boundary layer is estimated to be greater now than before the development of the ozone hole. Recent modeling studies have suggested that iodine and iodine-containing substances from natural sources, such as the ocean, may increase stratospheric ozone depletion significantly in polar regions during spring. Given the uncertainty of the fate of iodine in the stratosphere, the results may also be relevant for stratospheric ozone depletion and measurements of the influence of these substances on ozone depletion should be considered in the future. In agreement with

  6. Respiratory effects of air pollution on children.

    PubMed

    Goldizen, Fiona C; Sly, Peter D; Knibbs, Luke D

    2016-01-01

    A substantial proportion of the global burden of disease is directly or indirectly attributable to exposure to air pollution. Exposures occurring during the periods of organogenesis and rapid lung growth during fetal development and early post-natal life are especially damaging. In this State of the Art review, we discuss air toxicants impacting on children's respiratory health, routes of exposure with an emphasis on unique pathways relevant to young children, methods of exposure assessment and their limitations and the adverse health consequences of exposures. Finally, we point out gaps in knowledge and research needs in this area. A greater understanding of the adverse health consequences of exposure to air pollution in early life is required to encourage policy makers to reduce such exposures and improve human health.

  7. Impact of Aerosol Direct Effect on East Asian Air Quality During the EAST-AIRE Campaign

    NASA Astrophysics Data System (ADS)

    Wang, J.; Allen, D. J.; Pickering, K. E.; Li, Z.

    2015-12-01

    Three WRF-Chem simulations were conducted for East Asia region during March 2005 East Asian Studies of Tropospheric Aerosols: an International Regional Experiment (EAST-AIRE) Intensive Observation Campaign (IOC) period to investigate the direct effects of aerosols on surface radiation and air quality. WRF-Chem captured the temporal and spatial variations of meteorological fields, trace gases, and aerosol loadings. Surface shortwave radiation changes due to the aerosol direct effect (ADE) were calculated and compared with data from six World Radiation Data Center (WRDC) stations. The comparison indicated that WRF-Chem can simulate the surface short wave radiation moderately well, with temporal correlations between 0.4 and 0.7, and high biases between 9 to 120 W/m2. Domain-wide, WRF-Chem showed a decrease of 22 W/m2 in surface SW radiation due to the aerosol direct effect, consistent with observational studies. The ADE demonstrates diverse influences on air quality in East Asian. For example, the surface concentration of PM2.5 increases in eastern China (~11.1%) due to ADE, but decreases in central China (-7.3%), western China (-8.8%), and Sichuan Basin (-4%). Surface 1-hour maximum ozone is reduced by 2.3%, owing to less radiation reaching the surface due to the ADE. Since PM2.5 pollution raises serious public concern in China, regulations that control the emissions of PM2.5 and its precursors have been implemented. We investigate the impact of reducing two different types of aerosols, sulfate (scattering) and black carbon (absorbing), by cutting 80% of SO2 and black carbon (BC) emissions in two sensitivity simulations. We found that reducing SO2 emissions results in the decline of PM2.5 as much as 16mg/m3 in eastern China, and 20mg/m3 in the Sichuan Basin. Reducing the BC emissions by the same percentage causes the PM2.5 to decrease as much as 40mg/m3 in eastern China, and 25mg/m3 in the Sichuan Basin. The monthly averaged surface 1-hour maximum ozone increases 3

  8. Changes in tropospheric composition and air quality due to stratospheric ozone depletion.

    PubMed

    Solomon, Keith R; Tang, Xiaoyan; Wilson, Stephen R; Zanis, Prodromos; Bais, Alkiviadis F

    2003-01-01

    Increased UV-B through stratospheric ozone depletion leads to an increased chemical activity in the lower atmosphere (the troposphere). The effect of stratospheric ozone depletion on tropospheric ozone is small (though significant) compared to the ozone generated anthropogenically in areas already experiencing air pollution. Modeling and experimental studies suggest that the impacts of stratospheric ozone depletion on tropospheric ozone are different at different altitudes and for different chemical regimes. As a result the increase in ozone due to stratospheric ozone depletion may be greater in polluted regions. Attributable effects on concentrations are expected only in regions where local emissions make minor contributions. The vertical distribution of NOx (NO + NO2), the emission of volatile organic compounds and the abundance of water vapor, are important influencing factors. The long-term nature of stratospheric ozone depletion means that even a small increase in tropospheric ozone concentration can have a significant impact on human health and the environment. Trifluoroacetic acid (TFA) and chlorodifluoroacetic acid (CDFA) are produced by the atmospheric degradation of hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs). TFA has been measured in rain, rivers, lakes, and oceans, the ultimate sink for these and related compounds. Significant anthropogenic sources of TFA other than degradation HCFCs and HFCs have been identified. Toxicity tests under field conditions indicate that the concentrations of TFA and CDFA currently produced by the atmospheric degradation of HFCs and HCFCs do not present a risk to human health and the environment. The impact of the interaction between ozone depletion and future climate change is complex and a significant area of current research. For air quality and tropospheric composition, a range of physical parameters such as temperature, cloudiness and atmospheric transport will modify the impact of UV-B. Changes in the

  9. The effects of congestions tax on air quality and health

    NASA Astrophysics Data System (ADS)

    Johansson, Christer; Burman, Lars; Forsberg, Bertil

    The "Stockholm Trial" involved a road pricing system to improve the air quality and reduce traffic congestion. The test period of the trial was January 3-July 31, 2006. Vehicles travelling into and out of the charge cordon were charged for every passage during weekdays. The amount due varied during the day and was highest during rush hours (20 SEK = 2.2 EUR, maximum 60 SEK per day). Based on measured and modelled changes in road traffic it was estimated that this system resulted in a 15% reduction in total road use within the charged cordon. Total traffic emissions in this area of NO x and PM10 fell by 8.5% and 13%, respectively. Air quality dispersion modelling was applied to assess the effect of the emission reductions on ambient concentrations and population exposure. For the situations with and without the trial, meteorological conditions and other emissions than from road traffic were kept the same. The calculations show that, with a permanent congestion tax system like the Stockholm Trial, the annual average NO x concentrations would be lower by up to 12% along the most densely trafficked streets. PM10 concentrations would be up to 7% lower. The limit values for both PM10 and NO 2 would still be exceeded along the most densely trafficked streets. The total population exposure of NO x in Greater Stockholm (35 × 35 km with 1.44 million people) is estimated to decrease with a rather modest 0.23 μg m -3. However, based on a long-term epidemiological study, that found an increased mortality risk of 8% per 10 μg m -3 NO x, it is estimated that 27 premature deaths would be avoided every year. According to life-table analysis this would correspond to 206 years of life gained over 10 years per 100 000 people following the trial if the effects on exposures would persist. The effect on mortality is attributed to road traffic emissions (likely vehicle exhaust particles); NO x is merely regarded as an indicator of traffic exposure. This is only the tip of the ice

  10. The application of remote sensing techniques for air pollution analysis and climate change on Indian subcontinent

    NASA Astrophysics Data System (ADS)

    Palve, S. N.; Nemade, P. D., Dr.; Ghude, S. D., Dr.

    2016-06-01

    India is home to an extraordinary variety of climatic regions, ranging from tropical in the south to temperate and alpine in the Himalayan north, where elevated regions receive sustained winter snowfall. The subcontinent is characterized by high levels of air pollution due to intensively developing industries and mass fuel consumption for domestic purposes. The main tropospheric pollutants (O3, NO2, CO, formaldehyde (HCHO) and SO2) and two major greenhouse gases (tropospheric O3 and methane (CH4)) and important parameters of aerosols, which play a key role in climate change and affecting on the overall well-being of subcontinent residents. In light of considering these facts this paper aims to investigate possible impact of air pollutants over the climate change on Indian subcontinent. Satellite derived column aerosol optical depth (AOD) is a cost effective way to monitor and study aerosols distribution and effects over a long time period. AOD is found to be increasing rapidly since 2000 in summer season that may cause adverse effect to the agricultural crops and also to the human health. Increased aerosol loading may likely affect the rainfall which is responsible for the observed drought conditions over the Indian subcontinent. Carbon monoxide is emitted into the atmosphere by biomass burning activities and India is the second largest contributor of CO emissions in Asia. The MOPITT CO retrievals at 850 hPa show large CO emission from the IG region. The development of convective activity associated with the ASM leads to large scale vertical transport of the boundary layer CO from the Indian region into the upper troposphere. TCO over the Indian subcontinent during 2007 has a systematic and gradual variation, spatial as well as temporal. Higher amount of TCO in the northern latitudes and simultaneous lower TCO at near equatorial latitudes indicates depletion of ozone near the equator and accumulation at higher latitudes within the subcontinent. In addition, changes

  11. Air Change Rates and Interzonal Flows in Residences, and the Need for Multi-Zone Models for Exposure and Health Analysis

    EPA Science Inventory

    Air change rates (ACRs) and interzonal flows are key determinants of indoor air quality (IAQ) and building energy use. This paper characterizes ACRs and interzonal flows in 126 houses, and evaluates effects of these parameters on IAQ. ACRs measured using weeklong tracer measureme...

  12. Insect hygroreceptor responses to continuous changes in humidity and air pressure

    PubMed Central

    Tichy, H.; Kallina, W.

    2011-01-01

    The most favored model of humidity transduction views the cuticular wall of insect hygroreceptive sensilla as a hygromechanical transducer. Hygroscopic swelling or shrinking alters the geometry of the wall, deforming the dendritic membranes of the moist and dry cells. The small size the sensilla and their position surrounded by elevated structures creates technical difficulties to mechanically stimulate them by direct contact. The present study investigated hygroreceptors on the antennae of the cockroach and the stick insect. Accurately controlled, homogeneous mechanical input was delivered by modulating air pressure. Both the moist and dry cells responded not only to changes in air pressure, but also in the opposite direction, as observed during changes in air humidity. The moist-cell’s excitatory response to increasing humidity and increasing air pressure implies that swelling of the hygroscopic cuticle compresses the dendrites, and the dry-cell’s excitatory response to decreasing humidity and decreasing air pressure implies that shrinking of the hygroscopic cuticle expands the dendrites. The moist and dry cells of the stick insect are more sensitive to pressure changes than those of the cockroach, but the responses to air pressure are generally weaker than to humidity. Therefore, the hygroreceptive sensilla differ in their physical properties and constitutions. Furthermore, the mechanical parameters associated with homogeneous changes in air pressure on the sensillum surface can only partially account for the responses of the moist and dry cells of both species to humidity stimulation. PMID:20375249

  13. Low levels of air pollution induce changes of lung function in a panel of schoolchildren.

    PubMed

    Moshammer, H; Hutter, H-P; Hauck, H; Neuberger, M

    2006-06-01

    In search of sensitive screening parameters for assessing acute effects of ambient air pollutants in young schoolchildren, the impact of 8-h average air pollution before lung function testing was investigated by oscillatory measurements of resistance and spirometry with flow-volume loops. At a central elementary school in Linz, the capital of Upper Austria, 163 children aged 7-10 yrs underwent repeated examinations at the same time of day during 1 school year, yielding a total of 11-12 lung function tests per child. Associations to mass concentrations of particulate matter and nitrogen dioxide (NO(2)) measured continuously at a nearby monitoring station were tested, applying the Generalised Estimating Equations model. Reductions per 10 microg.m(-3) (both for particles and for NO(2)) were in the magnitude of 1% for most lung function parameters. The most sensitive indicator for acute effects of combustion-related pollutants was a change in maximal expiratory flow in small airways. NO(2) at concentrations below current standards reduced (in the multipollutant model) the forced expiratory volume in one second by 1.01%, maximal instantaneous forced flow when 50% of the forced vital capacity remains to be exhaled (MEF(50%)) by 1.99% and MEF(25%) by 1.96%. Peripheral resistance increased by 1.03% per 10 microg.m(-3) of particulate matter with a 50% cut-off aerodynamic diameter of 2.5 mum (PM(2.5)). Resistance is less influenced by the child's cooperation and should be utilised more often in environmental epidemiology when screening for early signs of small airway dysfunction from urban air pollution, but cannot replace the measurement of MEF(50%) and MEF(25%). In the basic model, the reduction of these parameters per 10 microg.m(-3) was highest for NO(2), followed by PM(1), PM(2.5) and PM(10), while exposure to coarse dust (PM(10)-PM(2.5)) did not change end-expiratory flow significantly. All acute effects of urban air pollution found on the lung function of healthy

  14. AIR POLLUTION EFFECTS ON SEMEN QUALITY

    EPA Science Inventory

    The potential impact of exposure to periods of high air pollution on male reproductive health was examined within the framework of an international project conducted in the Czech Republic. Semen quality was evaluated in young men (age 18) living in the Teplice District who are ex...

  15. Satellite Models for Global Environmental Change in the NASA Health and Air Quality Programs

    NASA Astrophysics Data System (ADS)

    Haynes, J.; Estes, S. M.

    2015-12-01

    Satellite remote sensing of the environment offers a unique vantage point that can fill in the gaps of environmental, spatial, and temporal data for tracking disease. Health and Air Quality providers and researchers are effective by the global environmental changes that are occurring and they need environmental data to study and understand the geographic, environmental, and meteorological differences in disease. This presentation maintains a diverse constellation of Earth observing research satellites and sponsors research in developing satellite data applications across a wide spectrum of areas including environmental health; infectious disease; air quality standards, policies, and regulations; and the impact of climate change on health and air quality. Successfully providing predictions with the accuracy and specificity required by decision makers will require advancements over current capabilities in a number of interrelated areas. These areas include observations, modeling systems, forecast development, application integration, and the research to operations transition process. This presentation will highlight many projects on which NASA satellites have been a primary partner with local, state, Federal, and international operational agencies over the past twelve years in these areas. Domestic and International officials have increasingly recognized links between environment and health. Health providers and researchers need environmental data to study and understand the geographic, environmental, and meteorological differences in disease. The presentation is directly related to Earth Observing systems and Global Health Surveillance and will present research results of the remote sensing environmental observations of earth and health applications, which can contribute to the health research. As part of NASA approach and methodology they have used Earth Observation Systems and Applications for Health Models to provide a method for bridging gaps of environmental

  16. Extreme weather and air pollution effects on cardiovascular and respiratory hospital admissions in Cyprus.

    PubMed

    Tsangari, H; Paschalidou, A K; Kassomenos, A P; Vardoulakis, S; Heaviside, C; Georgiou, K E; Yamasaki, E N

    2016-01-15

    In many regions of the world, climatic change is associated with increased extreme temperatures, which can have severe effects on mortality and morbidity. In this study, we examine the effect of extreme weather on hospital admissions in Cyprus, for inland and coastal areas, through the use of synoptic weather classifications (air mass types). In addition, the effect of particulate air pollution (PM10) on morbidity is examined. Our results show that two air mass types, namely (a) warm, rainy days with increased levels of water vapour in the atmosphere and (b) cold, cloudy days with increased levels of precipitation, were associated with increased morbidity in the form of hospital admissions. This was true both for cardiovascular and respiratory conditions, for all age groups, but particularly for the elderly, aged over 65. Particulate air pollution was also associated with increased morbidity in Cyprus, where the effect was more pronounced for cardiovascular diseases.

  17. Simulation of climate change impacts on grain sorghum production grown under free air CO2 enrichment

    NASA Astrophysics Data System (ADS)

    Fu, Tongcheng; Ko, Jonghan; Wall, Gerard W.; Pinter, Paul J.; Kimball, Bruce A.; Ottman, Michael J.; Kim, Han-Yong

    2016-07-01

    Potential impacts of climate change on grain sorghum (Sorghum bicolor) productivity were investigated using the CERES-sorghum model in the Decision Support System for Agrotechnology Transfer v4.5. The model was first calibrated for a sorghum cultivar grown in a free air CO2 enrichment experiment at the University of Arizona, Maricopa, Arizona, USA in 1998. The model was then validated with an independent dataset collected in 1999. The simulated grain yield, growth, and soil water of sorghum for the both years were in statistical agreement with the corresponding measurements, respectively. Neither simulated nor measured yields responded to elevated CO2, but both were sensitive to water supply. The validated model was then applied to simulate possible effects of climate change on sorghum grain yield and water use efficiency in western North America for the years 2080-2100. The projected CO2 fertilizer effect on grain yield was dominated by the adverse effect of projected temperature increases. Therefore, temperature appears to be a dominant driver of the global climate change influencing future sorghum productivity. These results suggest that an increase in water demand for sorghum production should be anticipated in a future high-CO2 world.

  18. Effect of ionizing radiation on moist air systems

    SciTech Connect

    Reed, D.T.; Van Konynenburg, R.A.

    1987-12-31

    The radiation chemistry of nitrogen/oxygen/water systems is reviewed. General radiolytic effects in dry nitrogen/oxygen systems are relatively well characterized. Irradiation results in the formation of steady state concentrations of ozone, nitrous oxide and nitrogen dioxide. In closed systems, the concentration observed depends on the total dose, temperature and initial gas composition. Only three studies have been published that focus on the radiation chemistry of nitrogen/oxygen/water homogeneous gas systems. Mixed phase work that is relevant to the gaseous system is also summarized. The presence of water vapor results in the formation of nitric acid and significantly changes the chemistry observed in dry air systems. Mechanistic evidence from the studies reviewed are summarized and discussed in relation to characterizing the gas phase during the containment period of a repository in tuff.

  19. An Air Quality Data Analysis System for Interrelating Effects, Standards and Needed Source Reductions

    ERIC Educational Resources Information Center

    Larsen, Ralph I.

    1973-01-01

    Makes recommendations for a single air quality data system (using average time) for interrelating air pollution effects, air quality standards, air quality monitoring, diffusion calculations, source-reduction calculations, and emission standards. (JR)

  20. Air suspension characterisation and effectiveness of a variable area orifice

    NASA Astrophysics Data System (ADS)

    Alonso, A.; Giménez, J. G.; Nieto, J.; Vinolas, J.

    2010-12-01

    The air spring is one of the components that most affects vehicle comfort. This element usually makes up the main part of the secondary suspension, which introduces both stiffness and damping between the bogie and the car body. Therefore, a deep understanding of this element is necessary in order to study the comfort of a vehicle, the influence of different parameters and the ways to improve it. In this work, the effect of the air spring system on comfort is studied. To accomplish this, a typical pneumatic suspension composition is briefly studied as a first step. Then, the test bench developed to characterise air springs is described, presenting experimental results. Correlation of the results with some theoretical models is also addressed. Afterwards, the effect of the air spring system on comfort is analysed, and finally, improvements from introducing a variable area orifice in the pipe that joints the air spring and the surge reservoir are discussed.

  1. The effect of undissolved air on isochoric freezing.

    PubMed

    Perez, Pedro A; Preciado, Jessica; Carlson, Gary; DeLonzor, Russ; Rubinsky, Boris

    2016-06-01

    This study evaluates the effect of undissolved air on isochoric freezing of aqueous solutions. Isochoric freezing is concerned with freezing in a constant volume thermodynamic system. A possible advantage of the process is that it substantially reduces the percentage of ice in the system at every subzero temperature, relative to atmospheric freezing. At the pressures generated by isochoric freezing, or high pressure isobaric freezing, air cannot be considered an incompressible substance and the presence of undissolved air substantially increases the amount of ice that forms at any subfreezing temperature. This effect is measurable at air volumes as low as 1%. Therefore eliminating the undissolved air, or any separate gaseous phase, from the system is essential for retaining the properties of isochoric freezing.

  2. Which ornamental plant species effectively remove benzene from indoor air?

    NASA Astrophysics Data System (ADS)

    Liu, Yan-Ju; Mu, Yu-Jing; Zhu, Yong-Guan; Ding, Hui; Crystal Arens, Nan

    Phytoremediation—using plants to remove toxins—is an attractive and cost effective way to improve indoor air quality. This study screened ornamental plants for their ability to remove volatile organic compounds from air by fumigating 73 plant species with 150 ppb benzene, an important indoor air pollutant that poses a risk to human health. The 10 species found to be most effective at removing benzene from air were fumigated for two more days (8 h per day) to quantify their benzene removal capacity. Crassula portulacea, Hydrangea macrophylla, Cymbidium Golden Elf., Ficus microcarpa var. fuyuensis, Dendranthema morifolium, Citrus medica var. sarcodactylis, Dieffenbachia amoena cv. Tropic Snow; Spathiphyllum Supreme; Nephrolepis exaltata cv. Bostoniensis; Dracaena deremensis cv. Variegata emerged as the species with the greatest capacity to remove benzene from indoor air.

  3. 77 FR 47617 - Change of Names Given for the Performance Review Board for the Department of the Air Force.

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-09

    ... Department of the Air Force Change of Names Given for the Performance Review Board for the Department of the Air Force. AGENCY: Department of the Air Force, DOD. ACTION: Notice. SUMMARY: Notice is given to replace a member of the 2012 Performance Review Board for the Department of the Air Force....

  4. Land use changes and its impacts on air quality and atmospheric patterns

    NASA Astrophysics Data System (ADS)

    Freitas, E. D.; Mazzoli, C. R.; Martins, L. D.; Martins, J. A.; Carvalho, V.; Andrade, M.

    2013-05-01

    Possible modifications on atmospheric patterns and air quality caused by land use changes are discussed in this work. With the increasing interest in alternative energy sources, mainly due to the replacement of fossil fuels, large part of the Brazilian territory is being used for sugar cane cultivation. The resultant modifications in land use and some activities associated to this crop are studied with some detail through numerical modeling of the atmosphere. The same tool was applied to study the effect of surface type and emission sources over urban areas in the neighborhoods of the cultivated areas, in particular those located in the Metropolitan Area of Campinas, inside the state of São Paulo, Brazil. The main focus of this work was to identify some relationship between these two types of land use modification and its influence on the regional atmospheric circulation patterns and air quality over agricultural and urban areas affected by biomass burning and the traditional sources of pollutants, such as industries and vehicles. First, the effect of urban areas was analyzed and it was possible to identify typical patterns associated with urban heat islands, especially over the city of Campinas. In this region, air temperature differences up to 3 K were detected during night time. During the day, due to the atmospheric conditions of the studied period, this effect was not significant. Afterwards, the effect of sugar cane cultivated regions was discussed. The results show that the regions of sugar cane grow can significantly modify the surface energy fluxes, with direct consequences to the standards of local temperature and humidity and over nearby regions. Sensitivity tests were carried out during part of September, 2007, through the substitution of the sugar cane by a generic crop in the model, and show that during the day the cultivated areas can present temperatures up to 0,65 k higher than those in the case of the generic one. Throughout the dispersion module

  5. Potential impact of a US climate policy and air quality regulations on future air quality and climate change

    NASA Astrophysics Data System (ADS)

    Lee, Y. H.; Shindell, D. T.; Faluvegi, G.; Pinder, R. W.

    2015-11-01

    We have investigated how future air quality and climate change are influenced by the US air quality regulations that existed or were proposed in 2013 and a hypothetical climate mitigation policy that reduces 2050 CO2 emissions to be 50 % below 2005 emissions. Using NASA GISS ModelE2, we look at the impacts in year 2030 and 2055. The US energy-sector emissions are from the GLIMPSE project (GEOS-Chem LIDORT Integrated with MARKAL for the Purpose of Scenario Exploration), and other US emissions and the rest of the world emissions are based on the RCP4.5 scenario. The US air quality regulations are projected to have a strong beneficial impact on US air quality and public health in the future but result in positive radiative forcing. Surface PM2.5 is reduced by ~ 2 μg m-3 on average over the US, and surface ozone by ~ 8 ppbv. The improved air quality prevents about 91 400 premature deaths in the US, mainly due to the PM2.5 reduction (~ 74 200 lives saved). The air quality regulations reduces the light-reflecting aerosols (i.e., sulfate and organic matter) more than the light-absorbing species (i.e., black carbon and ozone), leading a strong positive radiative forcing (RF) by both aerosols direct and indirect forcing: total RF is ~ 0.04 W m-2 over the globe; ~ 0.8 W m-2 over the US. Under the hypothetical climate policy, future US energy relies less on coal and thus SO2 emissions are noticeably reduced. This provides air quality co-benefits, but it leads to climate dis-benefits over the US. In 2055, the US mean total RF is +0.22 W m-2 due to positive aerosol direct and indirect forcing, while the global mean total RF is -0.06 W m-2 due to the dominant negative CO2 RF (instantaneous RF). To achieve a regional-scale climate benefit via a climate policy, it is critical (1) to have multi-national efforts to reduce GHGs emissions and (2) to target emission reduction of light-absorbing species (e.g., BC and O3) on top of long-lived species. The latter is very desirable as the

  6. Job Dissatisfaction among Air Force Clinical Nurses: Causes and Ways to Change It.

    DTIC Science & Technology

    1988-01-01

    34 burnout " syndrome . 4. Reports indicate clinical nurses are providing effective, quality nursing care to patients in Air Force medical treatment facilities...clinical nurses are falling victim to " burnout " syndrome , which in turn is affecting their job satisfaction. Air Force clinical inpatient nurses are managing

  7. Investigating the Effects of Traffic on Air Pollution.

    ERIC Educational Resources Information Center

    Taylor, Sharon

    2001-01-01

    Discusses the benefits of bringing scientists into the classroom to collaborate with children on environmental research projects. Describes one collaborative project that focused on the effects of traffic on air pollution. (DDR)

  8. Downscaling a Global Climate Model to Simulate Climate Change Impacts on U.S. Regional and Urban Air Quality

    NASA Technical Reports Server (NTRS)

    Trail, M.; Tsimpidi, A. P.; Liu, P.; Tsigaridis, K.; Hu, Y.; Nenes, A.; Russell, A. G.

    2013-01-01

    Climate change can exacerbate future regional air pollution events by making conditions more favorable to form high levels of ozone. In this study, we use spectral nudging with WRF to downscale NASA earth system GISS modelE2 results during the years 2006 to 2010 and 2048 to 2052 over the continental United States in order to compare the resulting meteorological fields from the air quality perspective during the four seasons of five-year historic and future climatological periods. GISS results are used as initial and boundary conditions by the WRF RCM to produce hourly meteorological fields. The downscaling technique and choice of physics parameterizations used are evaluated by comparing them with in situ observations. This study investigates changes of similar regional climate conditions down to a 12km by 12km resolution, as well as the effect of evolving climate conditions on the air quality at major U.S. cities. The high resolution simulations produce somewhat different results than the coarse resolution simulations in some regions. Also, through the analysis of the meteorological variables that most strongly influence air quality, we find consistent changes in regional climate that would enhance ozone levels in four regions of the U.S. during fall (Western U.S., Texas, Northeastern, and Southeastern U.S), one region during summer (Texas), and one region where changes potentially would lead to better air quality during spring (Northeast). We also find that daily peak temperatures tend to increase in most major cities in the U.S. which would increase the risk of health problems associated with heat stress. Future work will address a more comprehensive assessment of emissions and chemistry involved in the formation and removal of air pollutants.

  9. Air Quality from Early Pittsburgh to the Present: The Science of Change

    NASA Astrophysics Data System (ADS)

    Davidson, Cliff

    2009-03-01

    Throughout Pittsburgh's history over the past 250 years, coal reserves in the city and nearby have influenced its economy, demographics, and environmental quality. They have also played a major role in determining air quality in the region. For example, Pittsburgh became famous for its high particle loadings as early as the beginning of the nineteenth century, when the first complaints about air quality in the city were recorded. Nevertheless, residents tolerated the high coal smoke levels since jobs depended on the iron works, steel mills, and other industries. When natural gas was discovered just east of the city in the 1870's and replaced coal for some applications, particle concentrations decreased. But the local supplies of natural gas ran short several years later, and as industry continued to expand in the 1890's the city went back to the use of coal as its primary fuel. The return to smoky air was met with resistance that marked the beginning of sustained public outcry and initiation of several air pollution studies. The next half century was marked by periods of occasional high and low concentration, the latter due to events such as the financial panic of 1907 and the depression of the 1930's. It was not until the 1940's that effective regulations were passed to reduce smoky conditions. Particle levels fell throughout the 1950's and 1960's, and eventually the decline of heavy industry in Pittsburgh led to relatively clean air in many parts of the city. Over the past few decades, airborne particle concentrations averaged across the Pittsburgh region have remained below their earlier levels. However, there are still ``hot spots'' of high concentration resulting from regional background coming from upwind areas and emissions of some large sources that have continued to operate in the Pittsburgh region. Furthermore, the composition of airborne particles in the city has changed from earlier times. Such particles are now the result of emissions from sources in

  10. Impact of 2050 climate change on North American wildfire: consequences for ozone air quality

    NASA Astrophysics Data System (ADS)

    Yue, X.; Mickley, L. J.; Logan, J. A.; Hudman, R. C.; Martin, M. V.; Yantosca, R. M.

    2015-09-01

    We estimate future area burned in the Alaskan and Canadian forest by the mid-century (2046-2065) based on the simulated meteorology from 13 climate models under the A1B scenario. We develop ecoregion-dependent regressions using observed relationships between annual total area burned and a suite of meteorological variables and fire weather indices, and apply these regressions to the simulated meteorology. We find that for Alaska and western Canada, almost all models predict significant (p < 0.05) increases in area burned at the mid-century, with median values ranging from 150 to 390 %, depending on the ecoregion. Such changes are attributed to the higher surface air temperatures and 500 hPa geopotential heights relative to present day, which together lead to favorable conditions for wildfire spread. Elsewhere the model predictions are not as robust. For the central and southern Canadian ecoregions, the models predict increases in area burned of 45-90 %. Except for the Taiga Plain, where area burned decreases by 50 %, no robust trends are found in northern Canada, due to the competing effects of hotter weather and wetter conditions there. Using the GEOS-Chem chemical transport model, we find that changes in wildfire emissions alone increase mean summertime surface ozone levels by 5 ppbv for Alaska, 3 ppbv for Canada, and 1 ppbv for the western US by the mid-century. In the northwestern US states, local wildfire emissions at the mid-century enhance surface ozone by an average of 1 ppbv, while transport of boreal fire pollution further degrades ozone air quality by an additional 0.5 ppbv. The projected changes in wildfire activity increase daily summertime surface ozone above the 95th percentile by 1 ppbv in the northwestern US, 5 ppbv in the high latitudes of Canada, and 15 ppbv in Alaska, suggesting a greater frequency of pollution episodes in the future atmosphere.

  11. Biofuels that cause land-use change may have much larger non-GHG air quality emissions than fossil fuels.

    PubMed

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

    2012-10-02

    Although biofuels present an opportunity for renewable energy production, significant land-use change resulting from biofuels may contribute to negative environmental, economic, and social impacts. Here we examined non-GHG air pollution impacts from both indirect and direct land-use change caused by the anticipated expansion of Brazilian biofuels production. We synthesized information on fuel loading, combustion completeness, and emission factors, and developed a spatially explicit approach with uncertainty and sensitivity analyses to estimate air pollution emissions. The land-use change emissions, ranging from 6.7 to 26.4 Tg PM(2.5), were dominated by deforestation burning practices associated with indirect land-use change. We also found Brazilian sugar cane ethanol and soybean biodiesel including direct and indirect land-use change effects have much larger life-cycle emissions than conventional fossil fuels for six regulated air pollutants. The emissions magnitude and uncertainty decrease with longer life-cycle integration periods. Results are conditional to the single LUC scenario employed here. After LUC uncertainty, the largest source of uncertainty in LUC emissions stems from the combustion completeness during deforestation. While current biofuels cropland burning policies in Brazil seek to reduce life-cycle emissions, these policies do not address the large emissions caused by indirect land-use change.

  12. Changes in Ultrastructure and Sensory Characteristics on Electro-magnetic and Air Blast Freezing of Beef during Frozen Storage

    PubMed Central

    2015-01-01

    The ultrastructure in the beef muscle of the electro-magnetic resonance and air blast freezing during the frozen storage, and the changes in the quality characteristics after thawing were evaluated. The size of ice crystal was small and evenly formed in the initial freezing period, and it showed that the size was increased as the storage period was elapsed (p<0.05). The beef stored by the electro-magnetic resonance freezing showed the size of ice crystal with a lower rate of increase than the air blast freezing during the frozen storage. The thawing loss of beef stored by the electro-magnetic resonance freezing was significantly lower than the air blast freezing during frozen storage (p<0.05), and it showed that the thawing loss of the round was higher than the loin. Water holding capacity decreased as the storage period became longer while the electro-magnetic resonance freezing was higher than the air blast on 8 month (p<0.05). As a result of sensory evaluation, the beef stored by the electro-magnetic resonance freezing did not show the difference until 4 months, and it showed higher acceptability in comparison with the beef stored by the air blast freezing. Thus, it is considered that the freezing method has an effect on the change in the ultrastructure and quality characteristics of the beef. PMID:26761797

  13. Changes in Ultrastructure and Sensory Characteristics on Electro-magnetic and Air Blast Freezing of Beef during Frozen Storage.

    PubMed

    Choi, Yun-Sang; Ku, Su-Kyung; Jeong, Ji-Yun; Jeon, Ki-Hong; Kim, Young-Boong

    2015-01-01

    The ultrastructure in the beef muscle of the electro-magnetic resonance and air blast freezing during the frozen storage, and the changes in the quality characteristics after thawing were evaluated. The size of ice crystal was small and evenly formed in the initial freezing period, and it showed that the size was increased as the storage period was elapsed (p<0.05). The beef stored by the electro-magnetic resonance freezing showed the size of ice crystal with a lower rate of increase than the air blast freezing during the frozen storage. The thawing loss of beef stored by the electro-magnetic resonance freezing was significantly lower than the air blast freezing during frozen storage (p<0.05), and it showed that the thawing loss of the round was higher than the loin. Water holding capacity decreased as the storage period became longer while the electro-magnetic resonance freezing was higher than the air blast on 8 month (p<0.05). As a result of sensory evaluation, the beef stored by the electro-magnetic resonance freezing did not show the difference until 4 months, and it showed higher acceptability in comparison with the beef stored by the air blast freezing. Thus, it is considered that the freezing method has an effect on the change in the ultrastructure and quality characteristics of the beef.

  14. The Adverse Effects of Air Pollution on the Nervous System

    PubMed Central

    Genc, Sermin; Zadeoglulari, Zeynep; Fuss, Stefan H.; Genc, Kursad

    2012-01-01

    Exposure to ambient air pollution is a serious and common public health concern associated with growing morbidity and mortality worldwide. In the last decades, the adverse effects of air pollution on the pulmonary and cardiovascular systems have been well established in a series of major epidemiological and observational studies. In the recent past, air pollution has also been associated with diseases of the central nervous system (CNS), including stroke, Alzheimer's disease, Parkinson's disease, and neurodevelopmental disorders. It has been demonstrated that various components of air pollution, such as nanosized particles, can easily translocate to the CNS where they can activate innate immune responses. Furthermore, systemic inflammation arising from the pulmonary or cardiovascular system can affect CNS health. Despite intense studies on the health effects of ambient air pollution, the underlying molecular mechanisms of susceptibility and disease remain largely elusive. However, emerging evidence suggests that air pollution-induced neuroinflammation, oxidative stress, microglial activation, cerebrovascular dysfunction, and alterations in the blood-brain barrier contribute to CNS pathology. A better understanding of the mediators and mechanisms will enable the development of new strategies to protect individuals at risk and to reduce detrimental effects of air pollution on the nervous system and mental health. PMID:22523490

  15. Register Closing Effects on Forced Air Heating System Performance

    SciTech Connect

    Walker, Iain S.

    2003-11-01

    Closing registers in forced air heating systems and leaving some rooms in a house unconditioned has been suggested as a method of quickly saving energy for California consumers. This study combined laboratory measurements of the changes in duct leakage as registers are closed together with modeling techniques to estimate the changes in energy use attributed to closing registers. The results of this study showed that register closing led to increased energy use for a typical California house over a wide combination of climate, duct leakage and number of closed registers. The reduction in building thermal loads due to conditioning only a part of the house was offset by increased duct system losses; mostly due to increased duct leakage. Therefore, the register closing technique is not recommended as a viable energy saving strategy for California houses with ducts located outside conditioned space. The energy penalty associated with the register closing technique was found to be minimized if registers furthest from the air handler are closed first because this tends to only affect the pressures and air leakage for the closed off branch. Closing registers nearer the air handler tends to increase the pressures and air leakage for the whole system. Closing too many registers (more than 60%) is not recommended because the added flow resistance severely restricts the air flow though the system leading to safety concerns. For example, furnaces may operate on the high-limit switch and cooling systems may suffer from frozen coils.

  16. Air pollution effects on the structure of Citrus aurantium leaves

    SciTech Connect

    Psaras, G.K.; Christodoulakis, N.S.

    1987-09-01

    Individual air pollutants cause acute and chronic plant injury, act on stomata and affect carbon dioxide exchange as well as plant growth and development. Inhibition of photosynthesis by several air pollutants has been reported repeatedly. Besides, structural modifications of cell organelles have been reported after fumigation by SO/sub 2/. Although chlorosis and subsequent necrosis are common phenomena caused by artificial treatment with pollutants, fine structural leaf characteristics of plants exposed to long-term air pollution in natural conditions are little explored. Light microscope examination of air pollution affected leaves of plants common in natural ecosystems of Athens' metropolitan area revealed chlorosis phenomena. Electron microscope examination of the leaves of a common subshrub of greek phryganic formations grown in a heavily air polluted natural ecosystem of Athens metropolitan area revealed pronounced ultrastructural anomalies of chloroplasts, mitochondria and microbodies of the mesophyll cells. This organelle destruction of the photosynthesizing tissue as well as the minimization of the ecosystem primary productivity are attributed to the compound action of several toxic air pollutants of the photochemical smog of Athens. This work describes the long-term air pollution effects on the structural features of the leaves of Citrus aurantium, a decorative species planted throughout the heavily air polluted city of Athens.

  17. Assessment of contribution of greenhouse gases, water vapour and cloudiness to global surface air temperature changes

    NASA Astrophysics Data System (ADS)

    Gusakova, Maria; Karlin, Lev N.

    2013-04-01

    A contribution of the basic greenhouse effect components to the changes of global surface air temperature (SAT) has been assessed. The Earth's energy budget and the longwave energy transformation, in particular, were considered to investigate the mechanism of the influence of greenhouse effect (GHE) on global SAT. As is known, some part of the outgoing terrestrial radiation is retained in the atmosphere by greenhouse gases (GHGs) such as CO2, CH4, N2O, water vapour (WV) and cloudiness. The analysis of the changes in global SAT, GHGs and WV concentrations for the period 1984 - 2010 has shown that these parameters have a trend to increase. The research into global cloudiness and the vertical distribution of cloud layers made it possible to trace both positive and negative trends, namely the increase of availability of middle and high clouds has a positive trend while the increase of availability of global clouds and low clouds have a negative trend. Making use of the regression analysis relationships between global SAT and the components of greenhouse effect were obtained. It is shown, that the availability of total clouds and low clouds result in climate cooling, while the availability of middle and high clouds cause the increase of global SAT. The analysis of these parameters made it possible to carry out parameterization of GHE. To identify non-anthropogenic possible reasons of global SAT changes the influence of GHE on global SAT has been analyzed, with El-Nino phenomenon being one of the possible reasons. It has been shown that the GHGs role in global SAT changes is not dominant.

  18. Potential Impact of a US Climate Policy and Air Quality Regulations on Future Air Quality and Climate Change

    NASA Technical Reports Server (NTRS)

    Lee, Y. H.; Faluvegi, Gregory S.

    2016-01-01

    We have investigated how future air quality and climate change are influenced by the US air quality regulations that existed or were proposed in 2013 and a hypothetical climate mitigation policy that aims to reduce 2050 CO2 emissions to be 50% below 2005 emissions. Using the NASA GISS ModelE2 general circulation model, we look at the impacts for year 2030 and 2055. The US energy-sector emissions are from the GLIMPSE project (GEOS-Chem LIDORT Integrated with MARKAL (MARKet ALlocation) for the Purpose of Scenario Exploration), and other US emissions data sets and the rest of the world emissions data sets are based on the RCP4.5 scenario. The US air quality regulations are projected to have a strong beneficial impact on US air quality and public health in year 2030 and 2055 but result in positive radiative forcing. Under this scenario, no more emission constraints are added after 2020, and the impacts on air quality and climate change are similar between year 2030 and 2055. Surface particulate matter with a diameter smaller than 2.5 micron PM(sub 2:5) is reduced by 2 approximately µg/m(sup -3) on average over the USA, and surface ozone by approximately 8 ppbv. The improved air quality prevents about 91 400 premature deaths in the USA, mainly due to the PM(sub 2:5) reduction approximately (74 200 lives saved). The air quality regulations reduce the light-reflecting aerosols (i.e., sulfate and organic matter) more than the light-absorbing species (i.e., black carbon and ozone), leading to a strong positive radiative forcing (RF) over the USA by both aerosols' direct and indirect forcing: the total RF is approximately 0.04 W m(sup -2) over the globe, and approximately 0.8 W m(sup -2) over the USA. Under the hypothetical climate policy, a future CO2 emissions cut is achieved in part by relying less on coal, and thus SO2 emissions are noticeably reduced. This provides air quality co-benefits, but it could lead to potential climate disbenefits over the USA. In 2055, the US

  19. Potential impact of a US climate policy and air quality regulations on future air quality and climate change

    NASA Astrophysics Data System (ADS)

    Lee, Yunha; Shindell, Drew T.; Faluvegi, Greg; Pinder, Rob W.

    2016-04-01

    We have investigated how future air quality and climate change are influenced by the US air quality regulations that existed or were proposed in 2013 and a hypothetical climate mitigation policy that aims to reduce 2050 CO2 emissions to be 50 % below 2005 emissions. Using the NASA GISS ModelE2 general circulation model, we look at the impacts for year 2030 and 2055. The US energy-sector emissions are from the GLIMPSE project (GEOS-Chem LIDORT Integrated with MARKAL (MARKet ALlocation) for the Purpose of Scenario Exploration), and other US emissions data sets and the rest of the world emissions data sets are based on the RCP4.5 scenario. The US air quality regulations are projected to have a strong beneficial impact on US air quality and public health in year 2030 and 2055 but result in positive radiative forcing. Under this scenario, no more emission constraints are added after 2020, and the impacts on air quality and climate change are similar between year 2030 and 2055. Surface particulate matter with a diameter smaller than 2.5 µm (PM2.5) is reduced by ˜ 2 µg m-3 on average over the USA, and surface ozone by ˜ 8 ppbv. The improved air quality prevents about 91 400 premature deaths in the USA, mainly due to the PM2.5 reduction (˜ 74 200 lives saved). The air quality regulations reduce the light-reflecting aerosols (i.e., sulfate and organic matter) more than the light-absorbing species (i.e., black carbon and ozone), leading to a strong positive radiative forcing (RF) over the USA by both aerosols' direct and indirect forcing: the total RF is ˜ 0.04 W m-2 over the globe, and ˜ 0.8 W m-2 over the USA. Under the hypothetical climate policy, a future CO2 emissions cut is achieved in part by relying less on coal, and thus SO2 emissions are noticeably reduced. This provides air quality co-benefits, but it could lead to potential climate disbenefits over the USA. In 2055, the US mean total RF is +0.22 W m-2 due to positive aerosol direct and indirect forcing

  20. Assessing changes in stratospheric mean age of air and fractional release using historical trace gas observations

    NASA Astrophysics Data System (ADS)

    Laube, Johannes; Bönisch, Harald; Engel, Andreas; Röckmann, Thomas; Sturges, William

    2014-05-01

    Large-scale stratospheric transport is pre-dominantly governed by the Brewer-Dobson circulation. Due to climatic change a long-term acceleration of this residual stratospheric circulation has been proposed (e.g. Austin et al.,2006). Observational evidence has revealed indications for temporary changes (e.g. Bönisch et al., 2011) but a confirmation of a significant long-term trend is missing so far (e.g. Engel et al., 2009). A different aspect is a possible long-term change in the break-down of chemically important species such as chlorofluorocarbons as proposed by Butchart et al. 2001. Recent studies show significant differences adding up to more than 20 % in the chlorine released from such compounds (Newman et al., 2007; Laube et al., 2013). We here use a data set of three long-lived trace gases, namely SF6, CF2Cl2, and N2O, as measured in whole-air samples collected during balloon and aircraft flights between 1975 and 2011, to assess changes in stratospheric transport and chemistry. For this purpose we utilise the mean stratospheric transit times (or mean ages of air) in combination with a measure of the chemical decomposition (i.e. fractional release factors). We also evaluate the influence of different trend correction methods on these quantities and explore their variability with latitude, altitude, and season. References Austin, J. & Li, F.: On the relationship between the strength of the Brewer-Dobson circulation and the age of stratospheric air, Geophys. Res. Lett., 33, L17807, 2006. Bönisch, H., Engel, A., Birner, Th., Hoor, P., Tarasick, D. W., and Ray, E. A.: On the structural changes in the Brewer-Dobson circulation after 2000, Atmos. Chem. Phys., 11, 3937-3948, 2011. Butchart, N. & Scaife, A. A. Removal of chlorofluorocarbons by increased mass exchange between the stratosphere and troposphere in a changing climate. Nature, 410, 799-802, 2001. Engel, A., Möbius, T., Bönisch, H., Schmidt, U., Heinz, R., Levin, I., Atlas, E., Aoki, S., Nakazawa, T

  1. Changes in air quality and tropospheric composition due to depletion of stratospheric ozone and interactions with changing climate: implications for human and environmental health.

    PubMed

    Madronich, S; Shao, M; Wilson, S R; Solomon, K R; Longstreth, J D; Tang, X Y

    2015-01-01

    UV radiation is an essential driver for the formation of photochemical smog, which includes ground-level ozone and particulate matter (PM). Recent analyses support earlier work showing that poor outdoor air quality is a major environmental hazard as well as quantifying health effects on regional and global scales more accurately. Greater exposure to these pollutants has been linked to increased risks of cardiovascular and respiratory diseases in humans and is associated globally with several million premature deaths per year. Ozone also has adverse effects on yields of crops, leading to loss of billions of US dollars each year. These detrimental effects also may alter biological diversity and affect the function of natural ecosystems. Future air quality will depend mostly on changes in emission of pollutants and their precursors, but changes in UV radiation and climate will contribute as well. Significant reductions in emissions, mainly from the energy and transportation sectors, have already led to improved air quality in many locations. Air quality will continue to improve in those cities/states that can afford controls, and worsen where the regulatory infrastructure is not available. Future changes in UV radiation and climate will alter the rates of formation of ground-level ozone and photochemically-generated particulate matter and must be considered in predictions of air quality. The decrease in UV radiation associated with recovery of stratospheric ozone will, according to recent global atmospheric model simulations, lead to increases in ground-level ozone at most locations. If correct, this will add significantly to future ground-level ozone trends. However, the spatial resolution of these global models is insufficient to inform policy at this time, especially for urban areas. UV radiation affects the atmospheric concentration of hydroxyl radicals, ˙OH, which are responsible for the self-cleaning of the atmosphere. Recent measurements confirm that, on a

  2. Modeling the global levels and distribution of polychlorinated biphenyls in air under a climate change scenario.

    PubMed

    Lamon, Lara; Von Waldow, Harald; Macleod, Matthew; Scheringer, Martin; Marcomini, Antonio; Hungerbühler, Konrad

    2009-08-01

    We used the multimedia chemical fate model BETR Global to evaluate changes in the global distribution of two polychlorinated biphenyls, PCB 28 and PCB 153, under the influence of climate change. This was achieved by defining two climate scenarios based on results from a general circulation model, one scenario representing the last twenty years of the 20th century (20CE scenario) and another representing the global climate under the assumption of strong future greenhouse gas emissions (A2 scenario). The two climate scenarios are defined by four groups of environmental parameters: (1) temperature in the planetary boundary layer and the free atmosphere, (2) wind speeds and directions in the atmosphere, (3) current velocities and directions in the surface mixed layer of the oceans, and (4) rate and geographical pattern of precipitation. As a fifth parameter in our scenarios, we considerthe effect of temperature on primary volatilization emissions of PCBs. Comparison of dynamic model results using environmental parameters from the 20CE scenario against historical long-term monitoring data of concentrations of PCB 28 and PCB 153 in air from 16 different sites shows satisfactory agreement between modeled and measured PCBs concentrations. The 20CE scenario and A2 scenario were compared using steady-state calculations and assuming the same source characteristics of PCBs. Temperature differences between the two scenarios is the dominant factor that determines the difference in PCB concentrations in air. The higher temperatures in the A2 scenario drive increased primary and secondary volatilization emissions of PCBs, and enhance transport from temperate regions to the Arctic. The largest relative increase in concentrations of both PCB congeners in air under the A2 scenario occurs in the high Arctic and the remote Pacific Ocean. Generally, higher wind speeds under the A2 scenario result in more efficient intercontinental transport of PCB 28 and PCB 153 compared to the 20CE

  3. Health effects of air quality regulations in Delhi, India

    NASA Astrophysics Data System (ADS)

    Foster, Andrew; Kumar, Naresh

    2011-03-01

    This, the first systematic study, quantifies the health effects of air quality regulations in Delhi, which adopted radical measures to improve air quality, including, for example, the conversion of all commercial vehicles to compressed natural gas (CNG), and the closure of polluting industries in residential areas from 2000 to 2002. Air pollution data, collected at 113 sites (spread across Delhi and its neighboring areas) from July-December 2003, were used to compute exposure at the place of residence of 3989 subjects. A socio-economic and respiratory health survey was administered in 1576 households. This survey collected time-use, residence histories, demographic information, and direct measurements of lung function with subjects. The optimal interpolation methods were used to link air pollution and respiratory health data at the place of their residence. Resident histories, in combination with secondary data, were used to impute cumulative exposure prior to the air-quality interventions, and the effects of recent air quality measures on lung function were then evaluated. Three important findings emerge from the analysis. First, the interventions were associated with a significant improvement in respiratory health. Second, the effect of these interventions varied significantly by gender and income. Third, consistent with a causal interpretation of these results, effects were the strongest among those individuals who spend a disproportionate share of their time out-of-doors.

  4. Ambient air temperature effects on the temperature of sewage sludge composting process.

    PubMed

    Huang, Qi-fei; Chen, Tong-bin; Gao, Ding; Huang, Ze-chun

    2005-01-01

    Using data obtained with a full-scale sewage sludge composting facility, this paper studied the effects of ambient air temperature on the composting temperature with varying volume ratios of sewage sludge and recycled compost to bulking agent. Two volume ratios were examined experimentally, 1: 0: 1 and 3: 1: 2. The results show that composting temperature was influenced by ambient air temperature and the influence was more significant when composting was in the temperature rising process: composting temperature changed 2.4-6.5 degrees C when ambient air temperature changed 13 degrees C. On the other hand, the influence was not significant when composting was in the high-temperature and/or temperature falling process: composting temperature changed 0.75-1.3 degrees C when ambient air temperature changed 8-15 degrees C. Hysteresis effect was observed in composting temperature's responses to ambient air temperature. When the ventilation capability of pile was excellent (at a volume ratio of 1:0:1), the hysteresis time was short and ranging 1.1-1.2 h. On the contrary, when the proportion of added bulking agent was low, therefore less porosity in the substrate (at a volume ratio of 3:1:2), the hysteresis time was long and ranging 1.9-3.1 h.

  5. Effect of timed secondary-air injection on automotive emissions

    NASA Technical Reports Server (NTRS)

    Coffin, K. P.

    1973-01-01

    A single cylinder of an automotive V-8 engine was fitted with an electronically timed system for the pulsed injection of secondary air. A straight-tube exhaust minimized any mixing other than that produced by secondary-air pulsing. The device was operated over a range of engine loads and speeds. Effects attributable to secondary-air pulsing were found, but emission levels were generally no better than using the engine's own injection system. Under nontypical fast-idle, no-load conditions, emission levels were reduced by roughly a factor of 2.

  6. Managing Chemotherapy Side Effects: Memory Changes

    MedlinePlus

    ... C ancer I nstitute Managing Chemotherapy Side Effects Memory Changes What is causing these changes? Your doctor ... thinking or remembering things Managing Chemotherapy Side Effects: Memory Changes Get help to remember things. Write down ...

  7. Air pollution may alter efforts to mitigate climate change

    NASA Astrophysics Data System (ADS)

    Yassaa, Noureddine

    2016-02-01

    Renewable energy, considered in the past as a mitigation option to climate change by reducing carbon emission, is now becoming a source of energy security and competing fossil fuels in many areas of the world. According to recent reports (e.g., IEA, IRENA, REN21), renewable energy has reached in 2014 a historical record of power generation capacity. With 1712 GW installed capacity in 2014, renewable energy represents 27.7% of the world's power generating capacity. Solar photovoltaic (PV) energy, conversion of solar light to electricity through solar panels, has increased to reach 177 GW mostly due to the political engagement for the deployment of renewable through targeted programs and the decrease of PV panels prize in the market (roughly 80% decrease since 2008 according to IRENA's report). Concentrated Solar Power (CSP), reaching a total capacity of 4.4 GW in 2014 (REN21 Report), is also demonstrating a clear growth and progresses have been made with regards to the efficiency, the storage capacity and the cost. In order to reduce the energy consumption and carbon emissions, water solar heaters are being installed in the rooftop of households and a total capacity of 406 GW thermal was recorded in 2014 (REN21 Report).

  8. Changes in regional meteorology induced by anthropogenic heat and their impacts on air quality in South China

    NASA Astrophysics Data System (ADS)

    Xie, Min; Zhu, Kuanguang; Wang, Tijian; Feng, Wen; Gao, Da; Li, Mengmeng; Li, Shu; Zhuang, Bingliang; Han, Yong; Chen, Pulong; Liao, Jingbiao

    2016-12-01

    Anthropogenic heat (AH) emissions from human activities can change the urban circulation and thereby affect the air pollution in and around cities. Based on statistic data, the spatial distribution of AH flux in South China is estimated. With the aid of the Weather Research and Forecasting model coupled with Chemistry (WRF/Chem), in which the AH parameterization is developed to incorporate the gridded AH emissions with temporal variation, simulations for January and July in 2014 are performed over South China. By analyzing the differences between the simulations with and without adding AH, the impact of AH on regional meteorology and air quality is quantified. The results show that the regional annual mean AH fluxes over South China are only 0.87 W m-2, but the values for the urban areas of the Pearl River Delta (PRD) region can be close to 60 W m-2. These AH emissions can significantly change the urban heat island and urban-breeze circulations in big cities. In the PRD city cluster, 2 m air temperature rises by 1.1° in January and over 0.5° in July, the planetary boundary layer height (PBLH) increases by 120 m in January and 90 m in July, 10 m wind speed is intensified to over 0.35 m s-1 in January and 0.3 m s-1 in July, and accumulative precipitation is enhanced by 20-40 % in July. These changes in meteorological conditions can significantly impact the spatial and vertical distributions of air pollutants. Due to the increases in PBLH, surface wind speed and upward vertical movement, the concentrations of primary air pollutants decrease near the surface and increase in the upper levels. But the vertical changes in O3 concentrations show the different patterns in different seasons. The surface O3 concentrations in big cities increase with maximum values of over 2.5 ppb in January, while O3 is reduced at the lower layers and increases at the upper layers above some megacities in July. This phenomenon can be attributed to the fact that chemical effects can play a

  9. Building America Case Study: Ventilation System Effectiveness and Tested Indoor Air Quality Impacts, Tyler, Texas

    SciTech Connect

    2015-08-01

    ?Ventilation system effectiveness testing was conducted at two unoccupied, single-family, detached lab homes at the University of Texas - Tyler. Five ventilation system tests were conducted with various whole-building ventilation systems. Multizone fan pressurization testing characterized building and zone enclosure leakage. PFT testing showed multizone air change rates and interzonal airflow filtration. Indoor air recirculation by a central air distribution system can help improve the exhaust ventilation system by way of air mixing and filtration. In contrast, the supply and balanced ventilation systems showed that there is a significant benefit to drawing outside air from a known outside location, and filtering and distributing that air. Compared to the Exhaust systems, the CFIS and ERV systems showed better ventilation air distribution and lower concentrations of particulates, formaldehyde and other VOCs. System improvement percentages were estimated based on four System Factor Categories: Balance, Distribution, Outside Air Source, and Recirculation Filtration. Recommended System Factors could be applied to reduce ventilation fan airflow rates relative to ASHRAE Standard 62.2 to save energy and reduce moisture control risk in humid climates. HVAC energy savings were predicted to be 8-10%, or $50-$75/year. Cumulative particle counts for six particle sizes, and formaldehyde and other Top 20 VOC concentrations were measured in multiple zones. The testing showed that single-point exhaust ventilation was inferior as a whole-house ventilation strategy.

  10. Turbulence and wave breaking effects on air-water gas exchange

    PubMed

    Boettcher; Fineberg; Lathrop

    2000-08-28

    We present an experimental characterization of the effects of turbulence and breaking gravity waves on air-water gas exchange in standing waves. We identify two regimes that govern aeration rates: turbulent transport when no wave breaking occurs and bubble dominated transport when wave breaking occurs. In both regimes, we correlate the qualitative changes in the aeration rate with corresponding changes in the wave dynamics. In the latter regime, the strongly enhanced aeration rate is correlated with measured acoustic emissions, indicating that bubble creation and dynamics dominate air-water exchange.

  11. Changes in U.S. Regional-Scale Air Quality at 2030 Simulated Using RCP 6.0

    NASA Astrophysics Data System (ADS)

    Nolte, C. G.; Otte, T.; Pinder, R. W.; Faluvegi, G.; Shindell, D. T.

    2012-12-01

    Recent improvements in air quality in the United States have been due to significant reductions in emissions of ozone and particulate matter (PM) precursors, and these downward emissions trends are expected to continue in the next few decades. To ensure that planned air quality regulations are robust under a range of possible future climates and to consider possible policy actions to mitigate climate change, it is important to characterize and understand the effects of climate change on air quality. Recent work by several research groups using global and regional models has demonstrated that there is a "climate penalty," in which climate change leads to increases in surface ozone levels in polluted continental regions. One approach to simulating future air quality at the regional scale is via dynamical downscaling, in which fields from a global climate model are used as input for a regional climate model, and these regional climate data are subsequently used for chemical transport modeling. However, recent studies using this approach have encountered problems with the downscaled regional climate fields, including unrealistic surface temperatures and misrepresentation of synoptic pressure patterns such as the Bermuda High. We developed a downscaling methodology and showed that it now reasonably simulates regional climate by evaluating it against historical data. In this work, regional climate simulations created by downscaling the NASA/GISS Model E2 global climate model are used as input for the Community Multiscale Air Quality (CMAQ) model. CMAQ simulations over the continental United States are conducted for two 11-year time slices, one representing current climate (1995-2005) and one following Representative Concentration Pathway 6.0 from 2025-2035. Anthropogenic emissions of ozone and PM precursors are held constant at year 2006 levels for both the current and future periods. In our presentation, we will examine the changes in ozone and PM concentrations, with

  12. Impacts of grassland types and vegetation cover changes on surface air temperature in the regions of temperate grassland of China

    NASA Astrophysics Data System (ADS)

    Shen, Xiangjin; Liu, Binhui; Li, Guangdi; Yu, Pujia; Zhou, Daowei

    2016-10-01

    The sensitivity of surface air temperature response to different grassland types and vegetation cover changes in the regions of temperate grassland of China was analyzed by observation minus reanalysis (OMR) method. The basis of the OMR approach is that reanalysis data are insensitive to local surface properties, so the temperature differences between surface observations and reanalysis can be attributed to land effects. Results showed that growing-season air temperature increased by 0.592 °C/decade in the regions of temperate grassland of China, with about 31 % of observed warming associated with the effects of grassland types and vegetation cover changes. For different grassland types, the growing-season OMR trend was the strongest for temperate desert steppe (0.259 °C/decade) and the weakest for temperate meadow (0.114 °C/decade). Our results suggest that the stronger intraseasonal changes of grassland vegetation are present, the more sensitive the OMR trend responds to the intraseasonal vegetation cover changes. In August and September, the OMR of temperate meadow showed a weak cooling trend. For temperate meadow, about 72.2 and 72.6 % of surface cooling were explained by both grassland type and increase of vegetation cover for August and September, respectively. For temperate steppe and temperate desert steppe, due to the limited soil moisture and little evaporative cooling feedback, the vegetation changes have no significant effect on the surface air temperature. These results indicate that the impact of grassland types and vegetation cover changes should be considered when projecting further climate change in the temperate grassland region of China.

  13. Effects of air pollution on the skin: A review.

    PubMed

    Puri, Poonam; Nandar, Shashi Kumar; Kathuria, Sushruta; Ramesh, V

    2017-02-07

    The increase in air pollution over the years has had major effects on the human skin. Various air pollutants such as ultraviolet radiation, polycyclic aromatic hydrocarbons, volatile organic compounds, oxides, particulate matter, ozone and cigarette smoke affect the skin as it is the outermost barrier. Air pollutants damage the skin by inducing oxidative stress. Although human skin acts as a biological shield against pro-oxidative chemicals and physical air pollutants, prolonged or repetitive exposure to high levels of these pollutants may have profound negative effects on the skin. Exposure to ultraviolet radiation has been associated with extrinsic skin aging and skin cancers. Cigarette smoke contributes to premature aging and an increase in the incidence of psoriasis, acne and skin cancers. It is also implicated in allergic skin conditions such as atopic dermatitis and eczema. Polyaromatic hydrocarbons are associated with extrinsic skin aging, pigmentation, cancers and acneiform eruptions. Volatile organic compounds have been associated with atopic dermatitis. Given the increasing levels of air pollution and its detrimental effects on the skin, it is advisable to use strategies to decrease air pollution.

  14. Detailed Comparison of Blast Effects in Air and Vacuum

    SciTech Connect

    Tringe, J W; Molitoris, J D; Garza, R G; Andreski, H G; Batteux, J D; Lauderbach, L M; Vincent, E R; Wong, B M

    2007-07-26

    Although blast mitigation is most often achieved with solid shielding, ambient gas pressure can also affect the coupling of shock waves to solid targets. In this work the role of air as an energy transfer medium was examined experimentally by subjecting identical large-area rectangular witness plates to short-range blast effects in air and vacuum ({approx}50 mtorr) at 25 C. The expanding reactant front of 3 kg C4 charges was observed by fast camera to be cylindrically symmetric in both air and vacuum. The horizontal component of the reactant cloud velocity (perpendicular to the witness plates) was constant in both cases, with values of 3.0 and 5.9 km/s for air and vacuum, respectively. As a result of the blast, witness plates were plastically deformed into a shallow dish geometry, with local maxima 30 and 20 mm deep for air and vacuum, respectively. The average plate deflection from the air blast was 11 mm, {approx}10% deeper than the average vacuum plate deflection. Shock pressure estimates were made with a simple impedance-matching model, and indicate peak values in the 30-50 MPa range are consistent with the reactant cloud density and velocity. However, more detailed analysis is necessary to definitely establish the mechanisms by which air couples shock energy to the plates.

  15. The Effects of Very Light Jet Air Taxi Operations on Commercial Air Traffic

    NASA Technical Reports Server (NTRS)

    Smith, Jeremy C.; Dollyhigh, Samuel M.

    2006-01-01

    This study investigates the potential effects of Very Light Jet (VLJ) air taxi operations adding to delays experienced by commercial passenger air transportation in the year 2025. The affordable cost relative to existing business jets and ability to use many of the existing small, minimally equipped, but conveniently located airports is projected to stimulate a large demand for the aircraft. The resulting increase in air traffic operations will mainly be at smaller airports, but this study indicates that VLJs have the potential to increase further the pressure of demand at some medium and large airports, some of which are already operating at or near capacity at peak times. The additional delays to commercial passenger air transportation due to VLJ air taxi operations are obtained from simulation results using the Airspace Concepts Evaluation System (ACES) simulator. The direct increase in operating cost due to additional delays is estimated. VLJs will also cause an increase in traffic density, and this study shows increased potential for conflicts due to VLJ operations.

  16. An Optimization Approach to Analyzing the Effect of Supply Water and Air Temperatures in Planning an Air Conditioning System

    NASA Astrophysics Data System (ADS)

    Karino, Naoki; Shiba, Takashi; Yokoyama, Ryohei; Ito, Koichi

    In planning an air conditioning system, supply water and air temperatures are important factors from the viewpoint of cost reduction. For example, lower temperature supply water and air reduce the coefficient of performance of a refrigeration machine, and increase the thickness of heat insulation material. However, they enable larger temperature differences, and reduce equipment sizes and power demand. The purposes of this paper are to propose an optimal planning method for a cold air distribution system, and to analyze the effect of supply water and air temperatures on the long-term economics through a numerical study for an office building. As a result, it is shown that the proposed method effectively determines supply water and air temperatures for a cold air distribution system, and that the influence of supply air temperature is larger than that of supply water temperature on the long-term economics.

  17. Effects of travel mode on exposures to particulate air pollution.

    PubMed

    Briggs, David J; de Hoogh, Kees; Morris, Chloe; Gulliver, John

    2008-01-01

    Monitoring was carried out of particulate concentrations whilst simultaneously walking and driving 48 routes in London, UK. Monitoring was undertaken during May and June 2005. Route lengths ranged from 601 to 1351 m, and most routes were travelled in both directions. Individual journey times ranged from 1.5 to 15 min by car (average 3.7 min) and 7.3 to 30 min (average 12.8 min) whilst walking; car trips were therefore repeated up to 5 times for each single walking trip and the results averaged for the route. Car trips were made with windows closed and the ventilation system on a moderate setting. Results show that mean exposures while walking are greatly in excess of those while driving, by a factor 4.7 for the coarse particle mass (PM10-PM2.5), 2.2 for the fine particle mass (PM2.5-PM1), 1.9 for the very fine particle mass (air pollution present in the street. When account is also taken of the additional travel time involved in walking, these excesses are further increased: to factors of 15.6, 7.4, 6.5 and 4.4, respectively. Individuals who change their travel mode from car to walking in response to policies aimed at encouraging a modal shift in travel behavior are thus likely to experience considerably increased journey-time personal exposures to traffic-related air pollution. More effort is consequently needed to increase separation between road vehicles and pedestrians if negative effects of these policies are to be avoided.

  18. Air-leakage effects on stone cladding panels

    NASA Astrophysics Data System (ADS)

    Colantonio, Antonio

    1995-03-01

    This paper looks at the effects of air leakage on insulated stone clad precast panels used in present day construction of large commercial buildings. The building investigated was a newly built twenty story office building in a high density urban setting. Air leakage was suspected as a possible cause for thermal comfort complaints at isolated locations within the perimeter zones of the building. During the warrantee period the building owner asked for a quality control inspection of the air barrier assembly of the building envelope. Infrared thermography was used to locate areas of suspected air leakage within the building envelope. In order to differentiate thermal patterns produced by air leakage, conduction and convection as well as radiation from external sources, the building was inspected from the exterior; (1) after being pressurized for three hours, (2) one hour after the building was depressurized and (3) two and a half hours after total building depressurization was maintained by the building mechanical systems. Thermal images from similar locations were correlated for each time and pressure setting to verify air leakage locations within the building envelope. Areas exhibiting air leakage were identified and contractors were requested to carry out the necessary repairs. The pressure differential across the building envelope needs to be known in order to properly carry out an inspection to identify all locations of air leakage within a building envelope. As well the direction of the air movement and the density of the cladding material need to be accounted for in the proper inspection of these types of wall assemblies.

  19. Effects of climate change on aerosol concentrations in Europe

    NASA Astrophysics Data System (ADS)

    Megaritis, Athanasios G.; Fountoukis, Christos; Pandis, Spyros N.

    2013-04-01

    High concentrations of particulate matter less than 2.5 μm in size (PM2.5), ozone and other major constituents of air pollution, have adverse effects on human health, visibility and ecosystems (Seinfeld and Pandis, 2006), and are strongly influenced by meteorology. Emissions control policy is currently made assuming that climate will remain constant in the future. However, climate change over the next decades is expected to be significant (IPCC, 2007) and may impact local and regional air quality. Determining the sensitivity of the concentrations of air pollutants to climate change is an important step toward estimating future air quality. In this study we applied PMCAMx (Fountoukis et al., 2011), a three dimensional chemical transport model, over Europe, in order to quantify the individual effects of various meteorological parameters on fine particulate matter (PM2.5) concentrations. A suite of perturbations in various meteorological factors, such as temperature, wind speed, absolute humidity and precipitation were imposed separately on base case conditions to determine the sensitivities of PM2.5 concentrations and composition to these parameters. Different simulation periods (summer, autumn 2008 and winter 2009) are used to examine also the seasonal dependence of the air quality - climate interactions. The results of these sensitivity simulations suggest that there is an important link between changes in meteorology and PM2.5 levels. We quantify through separate sensitivity simulations the processes which are mainly responsible for the final predicted changes in PM2.5 concentration and composition. The predicted PM2.5 response to those meteorology perturbations was found to be quite variable in space and time. These results suggest that, the changes in concentrations caused by changes in climate should be taken into account in long-term air quality planning. References Fountoukis C., Racherla P. N., Denier van der Gon H. A. C., Polymeneas P., Charalampidis P. E

  20. 14 CFR 204.5 - Certificated and commuter air carriers undergoing or proposing to undergo substantial change in...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... undergoing or proposing to undergo substantial change in operations, ownership, or management. 204.5 Section..., ownership, or management. (a) A certificated or commuter air carrier proposing a substantial change in... operations, management, or ownership, including changes that may affect the air carrier's citizenship,...

  1. 14 CFR 204.5 - Certificated and commuter air carriers undergoing or proposing to undergo substantial change in...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... undergoing or proposing to undergo substantial change in operations, ownership, or management. 204.5 Section..., ownership, or management. (a) A certificated or commuter air carrier proposing a substantial change in... operations, management, or ownership, including changes that may affect the air carrier's citizenship,...

  2. [Attaching importance to study on acute health risk assessment and adaptation of air pollution and climate change].

    PubMed

    Shi, X M

    2017-03-10

    Air pollution and climate change have become key environmental and public health problems around the world, which poses serious threat to human health. How to assess and mitigate the health risks and increase the adaptation of the public have become an urgent topic of research in this area. The six papers in this issue will provide important and rich information on design, analysis method, indicator selection and setting about acute health risk assessment and adaptation study of air pollution and climate change in China, reflecting the advanced conceptions of multi-center and area-specific study and multi-pollutant causing acute effect study. However, the number and type of the cities included in these studies were still limited. In future, researchers should further expand detailed multi-center and multi-area study coverage, conduct area specific predicting and early warning study and strengthen adaptation study.

  3. Effective Stack Design in Air Pollution Control.

    ERIC Educational Resources Information Center

    Clarke, John H.

    1968-01-01

    Stack design problems fall into two general caterories--(1) those of building re-entry, and (2) those of general area pollution. Extensive research has developed adequate information, available in the literature, to permit effective stack design. A major roadblock to effective design has been the strong belief by architects and engineers that high…

  4. Auditory Effects of Multiple Impulses from a Seismic Air Gun on Bottlenose Dolphins (Tursiops truncatus).

    PubMed

    Schlundt, Carolyn E; Finneran, James J; Branstetter, Brian K; Trickey, Jennifer S; Bowman, Victoria; Jenkins, Keith

    2016-01-01

    Auditory thresholds were measured in three bottlenose dolphins before and after exposure to ten impulses from a seismic air gun. Thresholds were measured using behavioral and electrophysiological methods to determine the amount of temporary threshold shift induced. The results suggest that the potential for seismic surveys using air guns to cause auditory effects on dolphins may be lower than previously predicted; however, two of the three dolphins exhibited "anticipatory" behavioral changes at the highest exposure condition that suggested they were attempting to mitigate the effects of the exposures.

  5. Climate change and pollutant emissions impacts on air quality in 2050 over Portugal

    NASA Astrophysics Data System (ADS)

    Sá, E.; Martins, H.; Ferreira, J.; Marta-Almeida, M.; Rocha, A.; Carvalho, A.; Freitas, S.; Borrego, C.

    2016-04-01

    Changes in climate and air pollutant emissions will affect future air quality from global to urban scale. In this study, regional air quality simulations for historical and future periods are conducted, with CAMx version 6.0, to investigate the impacts of future climate and anthropogenic emission projections on air quality over Portugal and the Porto metropolitan area in 2050. The climate and the emission projections were derived from the Representative Concentrations Pathways (RCP8.5) scenario. Modelling results show that climate change will impact NO2, PM10 and O3 concentrations over Portugal. The NO2 and PM10 annual means will increase in Portugal and in the Porto municipality, and the maximum 8-hr daily O3 value will increase in the Porto suburban areas (approximately 5%) and decrease in the urban area (approximately 2%). When considering climate change and projected anthropogenic emissions, the NO2 annual mean decreases (approximately 50%); PM10 annual mean will increase in Portugal and decrease in Porto municipality (approximately 13%); however PM10 and O3 levels increase and extremes occur more often, surpassing the currently legislated annual limits and displaying a higher frequency of daily exceedances. This air quality degradation is likely to be related with the trends found for the 2046-2065 climate, which implies warmer and dryer conditions, and with the increase of background concentrations of ozone and particulate matter. The results demonstrate the need for Portuguese authorities and policy-makers to design and implement air quality management strategies that take climate change impacts into account.

  6. Influence of policy and climate change on air quality within the UK West Midlands plume

    NASA Astrophysics Data System (ADS)

    Walker, H. L.; Baker, J.

    2009-04-01

    The photochemical trajectory model (PTM), coupled with the Master Chemical Mechanism (MCM v3.1), was used to assess the contribution of locally emitted anthropogenic and biogenic emissions to ambient secondary pollutant levels recorded in Birmingham, UK during the summer Pollution in the Urban Midlands Atmosphere (PUMA) campaign (9 June - 12 July 1999). The contribution to ozone (and particulate matter) formation were found to be small, 0.0 to 3.2 ppb (0 to 11 %), with an overall average contribution of about 0.35 ppb or 1.0 % of the total ozone during the period. Subsequently, a stationary or slowly advecting boundary layer scenario was used to assess the timescales for which the local emissions within the West Midlands react and impact on secondary pollutant levels within or downwind of the region. Considering averaged biogenic and anthropogenic emissions across the region as representative of the West Midlands plume, the formation of ozone was found to be VOC-limited, and increased emissions of BVOCs were found to overall increase the reactivity of the plume. Future emissions scenarios were then modelled for 2010, 2015 and 2020 taking into account implementation of European legislation and possible climate change. This work reports on the predicted effects of these policy implementations and possible climate changes have on air quality within and downwind of the West Midlands connurbation.

  7. Effects of successive air and nitrox dives on human vascular function.

    PubMed

    Marinovic, Jasna; Ljubkovic, Marko; Breskovic, Toni; Gunjaca, Grgo; Obad, Ante; Modun, Darko; Bilopavlovic, Nada; Tsikas, Dimitrios; Dujic, Zeljko

    2012-06-01

    SCUBA diving is regularly associated with asymptomatic changes in cardiac, pulmonary and vascular function. The aim of this study was to evaluate the changes in vascular/endothelial function following SCUBA diving and to assess the potential difference between two breathing gases: air and nitrox 36 (36% oxygen and 64% nitrogen). Ten divers performed two 3-day diving series (no-decompression dive to 18 m with 47 min bottom time with air and nitrox, respectively), with 2 weeks pause in between. Arterial/endothelial function was assessed using SphygmoCor and flow-mediated dilation measurements, and concentration of nitrite before and after diving was determined in venous blood. Production of nitrogen bubbles post-dive was assessed by ultrasonic determination of venous gas bubble grade. Significantly higher bubbling was found after all air dives as compared to nitrox dives. Pulse wave velocity increased slightly (~6%), significantly after both air and nitrox diving, indicating an increase in arterial stiffness. However, augmentation index became significantly more negative after diving indicating smaller wave reflection. There was a trend for post-dive reduction of FMD after air dives; however, only nitrox diving significantly reduced FMD. No significant differences in blood nitrite before and after the dives were found. We found that nitrox diving affects systemic/vascular function more profoundly than air diving by reducing FMD response, most likely due to higher oxygen load. Both air and nitrox dives increased arterial stiffness, but decreased wave reflection suggesting a decrease in peripheral resistance due to exercise during diving. These effects of nitrox and air diving were not followed by changes in plasma nitrite.

  8. Water Vapor Storage Change in the Canopy-Air Space of a Tall Deciduous Forest

    NASA Astrophysics Data System (ADS)

    Wade, C.; Dragoni, D.; Schmid, H.

    2005-05-01

    The ability of weather and climate models to predict humidity, cloud formation and precipitation critically depends on the exchange of water vapor between vegetation and the atmosphere. The canopy air-space in tall forests is deep enough to act as a buffer volume that is depleted at times of well developed turbulent mixing, and gets recharged in conditions of poor mixing. Recent studies have attributed biases in modeled vapor exchange to the misrepresentation or neglect of this mechanism. At the Morgan-Monroe State Forest AmeriFlux site (Indiana, USA), water vapor exchange and the vapor storage change in the canopy air-space has been observed for the last six years. The objective of this work is to calculate vapor storage change fluxes in the canopy air-space from time increments of concentration profiles from data collected in 2003. We relate vapor storage change fluxes to measured environmental forcing quanitites, such as net radiation, ambient vapor pressure deficit, dew-point temperature depression, stability, and friction velocity to interpret the observed seasonal and daily patterns. Also, changes in water vapor storage rates are compared with measured latent heat fluxes to determine how the total forest-atmosphere vapor exchange is affected by the recharging and depletion of water vapor throughout the canopy air-space.

  9. The effects of negative air ions on various physiological functions during work in a hot environment

    NASA Astrophysics Data System (ADS)

    Inbar, O.; Rotstein, A.; Dlin, R.; Dotan, R.; Sulman, F. G.

    1982-06-01

    The effects of negative air-ions on human physical performance has been investigated. Twenty-one healthy males, 20 25 years old (X=23.6±2.6) were exposed to two 180-min rest and exercise sessions two weeks apart. The subjects were randomly assigned into either an experimental group (n=12) or to a control group (n=9). The experimental group performed the first session in neutral air conditions and the second one in air containing 1.36 to 1.90×105 negative air ions and 1.40 to 1.66×102 positive air ions/ml. The control group performed both sessions under neutral air conditions. All sessions were held at Ta=40±1‡C and 25±5% RH. Each session included one hour of resting under the respective ionization conditions, followed by 3 30-min cycle ergometer work bouts, separated by 7-min rest periods. The mechanical work-load during the bicycle exercise was 1.64±0.6 W/kg BW. The experimental group showed a significant reduction with negative air-ions in heart rate (HR), in rectal temperature, and in the rating of perceived exertion (RPE), all when compared with their own neutral session. The control group showed no significant changes between the first and the second exposure. Although not statistically significant, being exposed to negative air-ions seems also to reduce total sweat rate and minute ventilation (VE), and to increase O2 pulse. It is suggested that under the conditions of this study negative air ions can improve various cardiovascular and thermoregulatory functions as well as subjective feelings during physical effort. It is felt that such positive influences may be augmented by increasing the exposure time to negative ionized air and/or prolonging the stressful conditions.

  10. Effect of Outside Combustion Air on Gas Furnace Efficiency.

    DTIC Science & Technology

    1981-10-15

    Support Agency REPORT FESA-TS-2104 EFFECT OF OUTSIDE COMBUSTION AIR ON GAS FURNACE EFFICIENCY THOMAS E. BRISBANE Q KATHLEEN L. HANCOCK u JOHNS - MANVILLE SALES...and Dilution Air With No Furnace Setback. 93 AO-A113 4~84 . JOHNS - MANVILLE SALES CORP DENVER CO RESEARCH AND OEV--ETC F/6 13/ 1 EFFECT OF OUTSIDE...NUMBER(S) Thomas E. Brisbane, Kathleen L. Hancock DAAK 70-78-D-0002 9. PERFORMING ORGANIZATION NAME AND ADDRESS 1O. PROGRAM ELEMENT. PR.;ECT, TASK Johns

  11. Urban air pollution and climate change as environmental risk factors of respiratory allergy: an update.

    PubMed

    D'Amato, G; Cecchi, L; D'Amato, M; Liccardi, G

    2010-01-01

    The incidence of allergic respiratory diseases and bronchial asthma appears to be increasing worldwide, and people living in urban areas more frequently experience these conditions than those living in rural areas. One of the several causes of the rise in morbidity associated with allergic respiratory diseases is the increased presence of outdoor air pollutants resulting from more intense energy consumption and exhaust emissions from cars and other vehicles. Urban air pollution is now a serious public health hazard. Laboratory studies confirm epidemiologic evidence that air pollution adversely affects lung function in asthmatics. Damage to airway mucous membranes and impaired mucociliary clearance caused by air pollution may facilitate access of inhaled allergens to the cells of the immune system, thus promoting sensitization of the airway. Consequently, a more severe immunoglobulin (Ig) E-mediated response to aeroallergens and airway inflammation could account for increasing prevalence of allergic respiratory diseases in polluted urban areas. The most abundant components of urban air pollution in urban areas with high levels of vehicle traffic are airborne particulate matter, nitrogen dioxide, and ozone. In addition, the earth's temperature is increasing, mainly as a result of anthropogenic factors (e.g., fossil fuel combustion and greenhouse gas emissions from energy supply, transport, industry, and agriculture), and climate change alters the concentration and distribution of air pollutants and interferes with the seasonal presence of allergenic pollens in the atmosphere by prolonging these periods.

  12. Attribution of precipitation changes on ground-air temperature offset: Granger causality analysis

    NASA Astrophysics Data System (ADS)

    Cermak, Vladimir; Bodri, Louise

    2016-06-01

    This work examines the causal relationship between the value of the ground-air temperature offset and the precipitation changes for monitored 5-min data series together with their hourly and daily averages obtained at the Sporilov Geophysical Observatory (Prague). Shallow subsurface soil temperatures were monitored under four different land cover types (bare soil, sand, short-cut grass and asphalt). The ground surface temperature (GST) and surface air temperature (SAT) offset, ΔT(GST-SAT), is defined as the difference between the temperature measured at the depth of 2 cm below the surface and the air temperature measured at 5 cm above the surface. The results of the Granger causality test did not reveal any evidence of Granger causality for precipitation to ground-air temperature offsets on the daily scale of aggregation except for the asphalt pavement. On the contrary, a strong evidence of Granger causality for precipitation to the ground-air temperature offsets was found on the hourly scale of aggregation for all land cover types except for the sand surface cover. All results are sensitive to the lag choice of the autoregressive model. On the whole, obtained results contain valuable information on the delay time of ΔT(GST-SAT) caused by the rainfall events and confirmed the importance of using autoregressive models to understand the ground-air temperature relationship.

  13. The Potential Impacts of Climate Change on Air Quality in the Upper Northern Thailand

    NASA Astrophysics Data System (ADS)

    Chotamonsak, Chakrit; Salathé, Eric P.; Kreasuwun, Jiemjai

    2016-04-01

    In this study, the Weather Research and Forecasting (WRF) model were used as regional climate model to dynamically downscale the ECHAM5 Global Climate Model projection for the regional climate change impact on air quality-related meteorological conditions in the upper northern Thailand. The analyses were focused on meteorological variables that potentially impact on the regional air quality such as sea level pressure, planetary boundary layer height (PBLH), surface temperature, wind speed and ventilation. Comparisons were made between the present (1990-2009) and future (2045-2064) climate downscaling results during majority air pollution season (dry season, January-April). Analyses showed that the sea level pressure will be stronger in the future, suggesting more stable atmosphere. Increases in temperature were obvious observed throughout the region. Decreases in the surface wind and PBLH were predicted during air pollution season, indicating weaker ventilation rate in this region. Consequently, air quality-related meteorological variables were predicted to change in almost part of the upper northern Thailand, yielding a favorable meteorological condition for pollutant accumulation in the future.

  14. Effect of body repositioning after venous air embolism. An echocardiographic study

    NASA Technical Reports Server (NTRS)

    Geissler, H. J.; Allen, S. J.; Mehlhorn, U.; Davis, K. L.; Morris, W. P.; Butler, B. D.

    1997-01-01

    BACKGROUND: Current therapy for massive venous air embolism (VAE) may include the use of the left lateral recumbent (LLR) position, although its effectiveness has been questioned. This study used transesophageal echocardiography to evaluate the effect of body repositioning on intracardiac air and acute cardiac dimension changes. METHODS: Eighteen anesthetized dogs in the supine position received a venous air injection of 2.5 ml/kg at a rate of 5 ml/ s. After 1 min the dogs were repositioned into either the LLR, LLR 10 degrees head down (LLR-10 degrees), right lateral recumbence, or remained in the supine position. RESULTS: Repositioning after VAE resulted in relocation of intracardiac air to nondependent areas of the right heart. Peak right ventricular (RV) diameter increase and mean arterial pressure decrease were greater in the repositioned animals compared with those in the supine position (P < 0.05). Right ventricular diameter and mean arterial pressure showed an inverse correlation (r = 0.81). Peak left atrial diameter decrease was greater in the LLR and LLR-10 degrees positions compared with the supine position (P < 0.05). Repositioning did not influence peak pulmonary artery pressure increase, and no correlation was found between RV diameter and pulmonary artery pressure. All animals showed electrocardiogram and echocardiographic changes reconcilable with myocardial ischemia. CONCLUSIONS: In dogs, body repositioning after VAE provided no benefit in hemodynamic performance or cardiac dimension changes, although relocation of intracardiac air was demonstrated. Right ventricular air did not appear to result in significant RV outflow obstruction, as pulmonary artery pressure increased uniformly in all groups and was not influenced by the relocation of intracardiac air. The combination of increased RV afterload and arterial hypotension, possibly with subsequent RV ischemia rather than RV outflow obstruction by an airlock appeared to be the primary mechanism for

  15. Solar Eclipse Effect on Shelter Air Temperature

    NASA Technical Reports Server (NTRS)

    Segal, M.; Turner, R. W.; Prusa, J.; Bitzer, R. J.; Finley, S. V.

    1996-01-01

    Decreases in shelter temperature during eclipse events were quantified on the basis of observations, numerical model simulations, and complementary conceptual evaluations. Observations for the annular eclipse on 10 May 1994 over the United States are presented, and these provide insights into the temporal and spatial changes in the shelter temperature. The observations indicated near-surface temperature drops of as much as 6 C. Numerical model simulations for this eclipse event, which provide a complementary evaluation of the spatial and temporal patterns of the temperature drops, predict similar decreases. Interrelationships between the temperature drop, degree of solar irradiance reduction, and timing of the peak eclipse are also evaluated for late spring, summer, and winter sun conditions. These simulations suggest that for total eclipses the drops in shelter temperature in midlatitudes can be as high as 7 C for a spring morning eclipse.

  16. A Synoptic Air Mass Approach to Defining Southwest U.S. Summer Duration and Change

    NASA Astrophysics Data System (ADS)

    Morrill, C.; Wachtel, C. J.; Godek, M. L.

    2015-12-01

    As the past decade was the warmest in the 110-year active record, and future Southwest warming is expected to be most intense in the summer season, it is important to have an updated atmospheric definition of what constitutes a Southwest summer. This is particularly true given the intensity of current drought conditions and that summers may be changing. Using weather-type data from the Spatial Synoptic Classification, this research aims to synoptically define the summer season in the Southwest since 1950. The Southwest is spatially described here by sub-region and 28 air mass stations within are chosen for air mass analysis. Daily air mass frequencies are examined to determine the dominant and less prevalent types annually and seasonally, from May to September. Then, frequencies in the middle of summer are compared to those in the seasonal fringe months to explore the possibility of a synoptic shift in the timing of the region's summer season. Finally, to further scrutinize how regional air mass frequencies have changed with time, the data are subdivided and evaluated for the 'Early record' (years prior to 1975) and 'Modern record' (post 1975). Frequency departures are tested for practical and statistical significance to characterize the strength of summer season variability. Results indicate that Dry Moderate air masses are the most common annually and in summer. Moist and transitional air masses tend to less frequent throughout the Southwest; however, frequencies vary greatly by sub-region. Wet and dry conditions are observed in accordance with the monsoon in some sub-regions, but not throughout the region. Significant changes in sub-regional air mass tendencies are identified that show the Early record experienced cooler air mass conditions (fewer tropical types and more moderate and cool types) than the Modern record. From a long-term synoptic air mass perspective, typical Southwest summers likely last from May to August. However, in the Modern record May

  17. Climate Change and Health Risks from Extreme Heat and Air Pollution in the Eastern United States

    NASA Astrophysics Data System (ADS)

    Limaye, V.; Vargo, J.; Harkey, M.; Holloway, T.; Meier, P.; Patz, J.

    2013-12-01

    Climate change is expected to exacerbate health risks from exposure to extreme heat and air pollution through both direct and indirect mechanisms. Directly, warmer ambient temperatures promote biogenic emissions of ozone precursors and favor the formation of ground-level ozone, while an anticipated increase in the frequency of stagnant air masses will allow fine particulates to accumulate. Indirectly, warmer summertime temperatures stimulate energy demand and exacerbate polluting emissions from the electricity sector. Thus, while technological adaptations such as air conditioning can reduce risks from exposures to extreme heat, they can trigger downstream damage to air quality and public health. Through an interdisciplinary modeling effort, we quantify the impacts of climate change on ambient temperatures, summer energy demand, air quality, and public health. The first phase of this work explores how climate change will directly impact the burden of heat-related mortality. Climatic patterns, demographic trends, and epidemiologic risk models suggest that populations in the eastern United States are likely to experience an increasing heat stress mortality burden in response to rising summertime air temperatures. We use North American Regional Climate Change Assessment Program modeling data to estimate mid-century 2-meter air temperatures and humidity across the eastern US from June-August, and quantify how long-term changes in actual and apparent temperatures from present-day will affect the annual burden of heat-related mortality across this region. With the US Environmental Protection Agency's Environmental Benefits Mapping and Analysis Program, we estimate health risks using concentration-response functions, which relate temperature increases to changes in annual mortality rates. We compare mid-century summertime temperature data, downscaled using the Weather Research and Forecasting model, to 2007 baseline temperatures at a 12 km resolution in order to estimate

  18. Environmental dust effects on aluminum surfaces in humid air ambient

    PubMed Central

    Yilbas, Bekir Sami; Hassan, Ghassan; Ali, Haider; Al-Aqeeli, Nasser

    2017-01-01

    Environmental dusts settle on surfaces and influence the performance of concentrated solar energy harvesting devices, such as aluminum troughs. The characteristics of environmental dust and the effects of mud formed from the dust particles as a result of water condensing in humid air conditions on an aluminum wafer surface are examined. The dissolution of alkaline and alkaline earth compounds in water condensate form a chemically active mud liquid with pH 8.2. Due to gravity, the mud liquid settles at the interface of the mud and the aluminum surface while forming locally scattered patches of liquid films. Once the mud liquid dries, adhesion work to remove the dry mud increases significantly. The mud liquid gives rise to the formation of pinholes and local pit sites on the aluminum surface. Morphological changes due to pit sites and residues of the dry mud on the aluminum surface lower the surface reflection after the removal of the dry mud from the surface. The characteristics of the aluminum surface can address the dust/mud-related limitations of reflective surfaces and may have implications for the reductions in the efficiencies of solar concentrated power systems. PMID:28378798

  19. Environmental dust effects on aluminum surfaces in humid air ambient.

    PubMed

    Yilbas, Bekir Sami; Hassan, Ghassan; Ali, Haider; Al-Aqeeli, Nasser

    2017-04-05

    Environmental dusts settle on surfaces and influence the performance of concentrated solar energy harvesting devices, such as aluminum troughs. The characteristics of environmental dust and the effects of mud formed from the dust particles as a result of water condensing in humid air conditions on an aluminum wafer surface are examined. The dissolution of alkaline and alkaline earth compounds in water condensate form a chemically active mud liquid with pH 8.2. Due to gravity, the mud liquid settles at the interface of the mud and the aluminum surface while forming locally scattered patches of liquid films. Once the mud liquid dries, adhesion work to remove the dry mud increases significantly. The mud liquid gives rise to the formation of pinholes and local pit sites on the aluminum surface. Morphological changes due to pit sites and residues of the dry mud on the aluminum surface lower the surface reflection after the removal of the dry mud from the surface. The characteristics of the aluminum surface can address the dust/mud-related limitations of reflective surfaces and may have implications for the reductions in the efficiencies of solar concentrated power systems.

  20. Modeling green infrastructure land use changes on future air quality in Kansas City

    EPA Science Inventory

    Green infrastructure can be a cost-effective approach for reducing stormwater runoff and improving water quality as a result, but it could also bring co-benefits for air quality: less impervious surfaces and more vegetation can decrease the urban heat island effect, and also resu...

  1. Oil Palm expansion over Southeast Asia: land use change and air quality

    NASA Astrophysics Data System (ADS)

    Silva, S. J.; Heald, C. L.; Geddes, J.; Marlier, M. E.; Austin, K.; Kasibhatla, P. S.

    2015-12-01

    Over recent decades oil palm plantations have rapidly expanded across Southeast Asia (SEA). Much of this expansion has come at the expense of natural forests and grasslands. Aircraft measurements from a 2008 campaign, OP3, found that oil palm plantations emit as much as 7 times more isoprene than nearby natural forests. Furthermore, SEA is a rapidly developing region, with increasing urban population, and growing air quality concerns. Thus, SEA represents an ideal case study to examine the impacts of land use change on air quality in the region, and whether those changes can be detected from satellite observations of atmospheric composition. We investigate the impacts of historical and future oil palm expansion in SEA using satellite data, high-resolution land maps, and the chemical transport model GEOS-Chem. We examine the impact of palm plantations on surface-atmosphere processes (dry deposition, biogenic emissions). We show the sensitivity of air quality to current and future oil palm expansion scenarios, and discuss the limitations of current satellite measurements in capturing these changes. Our results indicate that while the impact of oil palm expansion on air quality can be significant, the retrieval error and sensitivity of the satellite measurements limit our ability to observe these impacts from space.

  2. Effect of glow discharge air plasma on grain crops seed

    SciTech Connect

    Dubinov, A.E.; Lazarenko, E.M.; Selemir, V.D.

    2000-02-01

    Oat and barley seeds have been exposed to both continuous and pulsed glow discharge plasmas in air to investigate the effects on germination and sprout growth. Statistical analysis was used to evaluate the effect of plasma exposure on the percentage germination and length of sprout growth. A stimulating effect of plasma exposure was found together with a strong dependence on whether continuous or pulsed discharges were used.

  3. Effectiveness of an air-cooled vest using selected air temperature and humidity combinations.

    PubMed

    Pimental, N A; Cosimini, H M; Sawka, M N; Wenger, C B

    1987-02-01

    We evaluated the effectiveness of an air-cooled vest in reducing thermal strain of subjects exercising in the heat (49 degrees C dry bulb (db), 20 degrees C dew point (dp] in chemical protective clothing. Four male subjects attempted 300-min heat exposures at two metabolic rates (175 and 315 W) with six cooling combinations--control (no vest) and five different db and dp combinations. Air supplied to the vest at 15 scfm ranged from 20-27 degrees C db, 7-18 degrees C dp; theoretical cooling capacities were 498-687 W. Without the vest, endurance times were 118 min (175 W) and 73 min (315 W). Endurance times with the vest were 300 min (175 W) and 242-300 min (315 W). The five cooling combinations were similarly effective in reducing thermal strain and extending endurance time, although there was a trend for the vest to be more effective when supplied with air at the lower dry bulb temperature. At 175 W, subjects maintained a constant body temperature; at 315 W, the vest's ability to extend endurance is limited to about 5 hours.

  4. Respiratory health effects of indoor air pollution.

    PubMed

    Perez-Padilla, R; Schilmann, A; Riojas-Rodriguez, H

    2010-09-01

    Domestic pollution is relevant to health because people spend most of their time indoors. One half of the world's population is exposed to high concentrations of solid fuel smoke (biomass and coal) that are produced by inefficient open fires, mainly in the rural areas of developing countries. Concentrations of particulate matter in kitchens increase to the range of milligrams per cubic meter during cooking. Solid fuel smoke possesses the majority of the toxins found in tobacco smoke and has also been associated with a variety of diseases, such as chronic obstructive pulmonary disease in women, acute respiratory infection in children and lung cancer in women (if exposed to coal smoke). Other tobacco smoke-associated diseases, such as tuberculosis, asthma, respiratory tract cancer and interstitial lung diseases, may also be associated with solid fuel smoke inhalation, but evidence is limited. As the desirable change to clean fuels is unlikely, efforts have been made to use efficient, vented wood or coal stoves, with varied success due to inconsistent acceptance by the community.

  5. Managing Chemotherapy Side Effects: Appetite Changes

    MedlinePlus

    ... ational C ancer I nstitute Managing Chemotherapy Side Effects Appetite Changes “Many days I’m just not ... are eating and drinking enough. Managing Chemotherapy Side Effects: Appetite Changes Keep this list on your refrigerator. ...

  6. What matters most: Are summer stream temperatures more sensitive to changing air temperature, changing discharge, or changing riparian vegetation under future climates?

    NASA Astrophysics Data System (ADS)

    Diabat, M.; Haggerty, R.; Wondzell, S. M.

    2012-12-01

    We investigated stream temperature responses to changes in both air temperature and stream discharge projected for 2040-2060 from downscaled GCMs and changes in the height and canopy density of streamside vegetation. We used Heat Source© calibrated for a 37 km section of the Middle Fork John Day River located in Oregon, USA. The analysis used the multiple-variable-at-a-time (MVAT) approach to simulate various combinations of changes: 3 levels of air warming, 5 levels of stream flow (higher and lower discharges), and 6 types of streamside vegetation. Preliminary results show that, under current discharge and riparian vegetation conditions, projected 2 to 4 °C increase in air temperature will increase the 7-day Average Daily Maximum Temperature (7dADM) by 1 to 2 °C. Changing stream discharge by ±30% changes stream temperature by ±0.5 °C, and the influence of changing discharge is greatest when the stream is poorly shaded. In contrast, the 7dADM could change by as much as 11°C with changes in riparian vegetation from unshaded conditions to heavily shaded conditions along the study section. The most heavily shaded simulations used uniformly dense riparian vegetation over the full 37-km reach, and this vegetation was composed of the tallest trees and densest canopies that can currently occur within the study reach. While this simulation represents an extreme case, it does suggest that managing riparian vegetation to substantially increase stream shade could decrease 7dADM temperatures relative to current temperatures, even under future climates when mean air temperatures have increased from 2 to 4 °C.

  7. A Study of the Effects of Air Pollution on Children

    ERIC Educational Resources Information Center

    Bury, Irene B.

    1970-01-01

    An investigation of the possible effects of air pollution on the absenteeism of elementary school children showed that a greater percent of absences occurred in the test group than in a comparable group. There is little question as to the importance that such information should have for educators, informed parents, and other adults in community…

  8. CARDIAC MOLECULAR EFFECTS INDUCED BY AIR POLLUTION PARTICLES

    EPA Science Inventory

    Abstract Submitted to the American Thoracic Society 98th International Conference, May 17 - 22, 2002, Atlanta, GA

    CARDIAC MOLECULAR EFFECTS INDUCED BY AIR POLLUTION PARTICLES
    K. Dreher1, R. Jaskot1, J. Richards1, and T. Knuckles2. 1U. S. Environmental Protection Agency,...

  9. Effects of air velocity on laying hen production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thermal conditions play a major role in production efficiency in commercial poultry production. Mitigation of thermal stress can improve productivity, but must be achieved economically. Weather and system design can limit effectiveness of evaporative cooling and increased air movement has been sho...

  10. The Effects of a Blizzard on Urban Air Pollution.

    ERIC Educational Resources Information Center

    da Silva, Armando; Bein, Frederick L.

    1981-01-01

    The chronology and effects of a 1978 blizzard on Indianapolis' air pollution levels (ozone, sulfur dioxide, carbon monoxide) are used as a case study for geography classes. Photographs, graphs, and maps are provided as examples of meteorological data collection and interpretation. (AM)

  11. European Air Quality and Climate Change: first steps of a numerical modeling study

    NASA Astrophysics Data System (ADS)

    Lacressonnière, Gwendoline; Peuch, Vincent-Henri; Josse, Béatrice; Joly, Mathieu; Martet, Maud

    2010-05-01

    In the context of climate change, the evolution of air quality in Europe is a challenging scientific question, despite the political measures taken to limit and reduce anthropogenic emissions. Heat waves, changes in transport pathways or synoptic patterns, increase of emissions in other areas in the world (in particular in Asia), or for instance possible increase of biogenic emissions may affect adversely future Air Quality levels in Europe. In the context of a project co-funded by the French environment agency ADEME, a numerical modeling study has begun relying on the tools used by Météo-France for its contribution to the 5th IPCC assessment report, to GMES atmospheric services (MACC FP7 project) and to the French national operational Air Quality platform Prév'Air (http://www.prevair.org). In particular, the MOCAGE 3-D chemical transport model (CTM) is used with a configuration comprising a global (2°) and a European domain (0.2°), allowing representation of both long-range transport of pollutants and European Air Quality at relevant resolutions and with a two-ways coupling. MOCAGE includes 47 layers from the surface to 5hPa. The first step of this project is to assess the impact of meteorological forcings, either analyses ("best" meteorology available for the recent past) or climate runs for the current atmosphere (interpolated on the same high resolution grid), on air quality hindcasts with MOCAGE over Europe. For these climate runs, we rely on Météo-France Earth-System model CNRM-CM, and particularly the ARPEGE-climate general circulation model for the atmosphere. By studying several key variables for Air Quality (surface and low troposphere concentrations of ozone, nitrogen oxides, volatile organic compounds, radicals, PM,…) we aim at investigating the indicators that are robust or not (monthly averages, frequency of exceedances, AOTs,…) for a given climate when using climatological forcings instead of analyses (reference), all the rest in the CTM

  12. Joint Effects of Ambient Air Pollutants on Pediatric Asthma ...

    EPA Pesticide Factsheets

    Background: Because ambient air pollution exposure occurs in the form of mixtures, consideration of joint effects of multiple pollutants may advance our understanding of air pollution health effects. Methods: We assessed the joint effect of selected ambient air pollutant combinations (groups of oxidant, secondary, traffic, power plant, and criteria pollutants constructed using combinations of criteria gases, fine particulate matter (PM2.5) and PM2.5 components) on warm season pediatric asthma emergency department (ED) visits in Atlanta during 1998-2004. Joint effects were assessed using multi-pollutant Poisson generalized linear models controlling for time trends, meteorology and daily non-asthma respiratory ED visit counts. Rate ratios (RR) were calculated for the combined effect of an interquartile-range increment in the concentration of each pollutant. Results: Increases in all of the selected pollutant combinations were associated with increases in pediatric asthma ED visits [e.g., joint effect rate ratio=1.13 (95% confidence interval 1.06-1.21) for criteria pollutants (including ozone, carbon monoxide, nitrogen dioxide, sulfur dioxide, and PM2.5)]. Joint effect estimates were smaller than estimates calculated based on summing results from single-pollutant models, due to control for confounding. Compared with models without interactions, joint effect estimates from models including first-order pollutant interactions were similar for oxidant a

  13. Effects of future anthropogenic pollution emissions on global air quality

    NASA Astrophysics Data System (ADS)

    Pozzer, A.; Zimmermann, P.; Doering, U.; van Aardenne, J.; Dentener, F.; Lelieveld, J.

    2012-04-01

    The atmospheric chemistry general circulation model EMAC is used to estimate the impact of anthropogenic emission changes on global and regional air quality in recent and future years (2005, 2010, 2025 and 2050). The emission scenario assumes that population and economic growth largely determine energy consumption and consequent pollution sources ("business as usual"). By comparing with recent observations, it is shown that the model reproduces the main features of regional air pollution distributions though with some imprecision inherent to the coarse horizontal resolution (around 100 km). To identify possible future hot spots of poor air quality, a multi pollutant index (MPI) has been applied. It appears that East and South Asia and the Arabian Gulf regions represent such hotspots due to very high pollutant concentrations. In East Asia a range of pollutant gases and particulate matter (PM2.5) are projected to reach very high levels from 2005 onward, while in South Asia air pollution, including ozone, will grow rapidly towards the middle of the century. Around the Arabian Gulf, where natural PM2.5 concentrations are already high (desert dust), ozone levels will increase strongly. By extending the MPI definition, we calculated a Per Capita MPI (PCMPI) in which we combined population projections with those of pollution emissions. It thus appears that a rapidly increasing number of people worldwide will experience reduced air quality during the first half of the 21st century. It is projected that air quality for the global average citizen in 2050 will be comparable to the average in East Asia in the year 2005.

  14. On the impact of entrapped air in infiltration under ponding conditions: Part a: Preferential air flow path effects on infiltration

    NASA Astrophysics Data System (ADS)

    Weisbord, N.; Mizrahi, G.; Furman, A.

    2015-12-01

    Entrapped air effects on infiltration under ponding conditions could be important for massive infiltration of managed aquifer recharge or soil aquifer treatment. Earlier studies found that under ponding conditions air could reduce infiltration by 70-90%. Most studies have dealt with entrapped air effects when soil surface topography is flat. The objective of this study is to investigate the effects of: (1) irregular surface topography on preferential air flow path development; (2) preferential air flow path on infiltration; and (3) hydraulic head on infiltration when air is trapped. Column experiments were used to investigate these particular effects. A 140 cm deep and 30 cm wide column packed with silica sand was used under two boundary conditions: in the first, air can only escape vertically upward through the soil surface; in the second, air is free to escape. The surface was flooded with 13 liters of water, with ponding depth decreasing with time. Two soil surface conditions were tested: flat surface and irregular. It was found that in irregular surfaces, stable air flow through preferential paths was developed in the high altitude zones. Flat surface topography caused unstable air flow through random paths. Comparison between irregular and flat surface topography showed that the entrapped air pressure was lower and the infiltration rate was about 40% higher in the irregular surface topography than in the flat surface topography. No difference of infiltration rate between flat and irregular surface topography was observed when air was free to escape along the infiltration path. It was also found that at the first stage of infiltration, higher hydraulic heads caused higher entrapped air pressures and lower infiltration rates. In contrast, higher hydraulic head results in higher infiltration rate, when air was free to escape. Our results suggest that during ponding conditions: (1) preferential air flow paths develop at high surface zones of irregular topography

  15. Effects of China's Energy Policy on Future Air Quality in China and the U.S.

    NASA Astrophysics Data System (ADS)

    Li, M.; Selin, N. E.; Karplus, V. J.; Li, C. T.; Zhang, D.; Luo, X.; Zhang, X.

    2014-12-01

    We examine the effects of recently announced energy policies in mainland China on air quality in both China and the U.S. in 2030. China is the largest contributor to global anthropogenic emissions of air pollutants, especially the precursors to ozone and fine particulate matter (PM2.5) such as nitrogen oxides (NOx) and sulfur dioxide (SO2). Efforts to limit coal use in China under the country's National Air Pollution Action Plan will reduce these air pollutants. Control efforts are expected to not only decrease the concentration of ozone and PM2.5 locally in China, but also reduce the trans-Pacific transport of air pollutants to the U.S. We couple an energy-economic model with sub-national detail for China (the China Regional Energy Model, or C-REM) to a global atmospheric chemistry model (GEOS-Chem) to assess air pollution reductions under an energy policy scenario relative to a no policy baseline scenario. Future Chinese anthropogenic emissions are predicted by C-REM under a national energy policy scenario which achieves a 20% reduction in energy intensity from 2012 to 2017 by targeting fossil fuel use nationwide as specified in the National Air Pollution Action Plan and also meets the Plan's sub-national constraint that coal use must not increase above present levels in three largest urban regions (the Beijing-Tianjin-Hebei Area, Yangtze River Delta, and Pearl River Delta) through 2030. Using GEOS-Chem, we project changes in the surface concentration of ozone and PM2.5 over China and the U.S. in 2030. We find that air pollutants decrease substantially over both China and the U.S. under the national targets set by the Air Pollution Action Plan.

  16. Epidemiologic evidence of cardiovascular effects of particulate air pollution.

    PubMed Central

    Dockery, D W

    2001-01-01

    In the past decade researchers have developed a body of epidemiologic evidence showing increased daily cardiovascular mortality and morbidity associated with acute exposures to particulate air pollution. Associations have been found not only with cardiovascular deaths reported on death certificates but also with myocardial infarctions and ventricular fibrillation. Particulate air pollution exposure has been associated with indicators of autonomic function of the heart including increased heart rate, decreased heart rate variability, and increased cardiac arrhythmias. Several markers of increased risk for sudden cardiac death have also been associated with such exposures. These epidemiologic studies provide early guidance to possible pathways of particulate air pollution health effects, which can only be addressed fully in toxicologic and physiologic studies. PMID:11544151

  17. Ground-level air pollution changes during a boreal wildland mega-fire.

    PubMed

    Bytnerowicz, Andrzej; Hsu, Yu-Mei; Percy, Kevin; Legge, Allan; Fenn, Mark E; Schilling, Susan; Frączek, Witold; Alexander, Diane

    2016-12-01

    The 2011 Richardson wildland mega-fire in the Athabasca Oil Sands Region (AOSR) in northern Alberta, Canada had large effects on air quality. At a receptor site in the center of the AOSR ambient PM2.5, O3, NO, NO2, SO2, NH3, HONO, HNO3, NH4(+) and NO3(-) were measured during the April-August 2011 period. Concentrations of NH3, HNO3, NO2, SO2 and O3 were also monitored across the AOSR with passive samplers, providing monthly summer and bi-monthly winter average values in 2010, 2011 and 2012. During the fire, hourly PM2.5 concentrations >450μgm(-3) were measured at the AMS 1 receptor site. The 24-h National Ambient Air Quality Standard (NAAQS) of 35μgm(-3) and the Canada Wide Standard (CWS) of 30μgm(-3) were exceeded on 13days in May and 7days in June. During the fire emission periods, sharp increases in NH3, HONO, HNO3, NH4(+), NO3(-) and total inorganic reactive N concentrations occurred, all closely correlated with the PM2.5 changes. There were large differences in the relative contribution of various N compounds to total inorganic N between the no-fire emission and fire emission periods. While in the absence of fires NO and NO2 dominated, their relative contribution during the fires was ~2 fold smaller, mainly due to increased NH3, NH4(+) and NO3(-). Concentrations of HONO and HNO3 also greatly increased during the fires, but their contribution to the total inorganic N pool was relatively small. Elevated NH3 and HNO3 concentrations affected large areas of northern Alberta during the Richardson Fire. While NH3 and HNO3 concentrations were not at levels considered toxic to plants, these gases contributed significantly to atmospheric N deposition. Generally, no significant changes in O3 and SO2 concentrations were detected and their ambient concentrations were below levels harmful to human health or sensitive vegetation.

  18. Effecting Change in Library Education.

    ERIC Educational Resources Information Center

    Hershfield, Allan F.

    While libraries, as a species of complex organization, may not be facing immediate extinction, the available evidence suggests their long-term survival prospects are not particularly encouraging. Libraries, in general, have not responded adequately to rapidly changing social, economic and political factors. The locus for change lies in library…

  19. Ecological effects of global change

    NASA Astrophysics Data System (ADS)

    Menzel, A.

    2010-03-01

    Mankind actually puts manifolds loads on our earth including stratospheric ozone depletion, rising freshwater use, changes of land cover and land use. For several of these threats, critical loads and thresholds may be already exceeded, e.g. nitrogen input, climate change and biodiversity loss (Röckström et al. 2009). The working group on Impacts, Adaptation and Vulnerability of the last IPCC report (AR4, 2007) concluded that anthropogenic warming over the last three decades has had a discernible influence on many physical and biological systems, thus global fingerprint of anthropogenic climate change was detectable on all continents and almost all ocean areas (Rosenzweig et al. 2007, 2008). 90% of the significant temperature related changes in 29000 records analysed were consistent with climate warming, e.g. in warming climates earlier spring events, distributional shifts pole wards and to higher altitudes, or community changes with reduced cold adapted species were observed. These impacts, already visible and only related to less than 1°C global warming, allow a limited glance at future changes and pressures on our ecosystems, as the rate of warming may accelerate and will be linked to stronger and more frequent extreme events. Vegetation is an important component of the climate system, part of biogeochemical cycles and the lower boundary of GCMs characterised by certain albedo and roughness. Thus, climate change impacts on vegetation exert feedbacks. The most striking and challenging problems in analysing climate change impacts on ecosystems are related to cases where one would expect major changes due to warming however there is reduced, limited or no reaction in the observed systems. This feature is known as divergence problem in tree ring research, called resilience in ecosystem dynamics or might be simply a time-lag or environmental monitoring problem. However, there are various other pressures by global change, e.g. land use change or pollution, leading

  20. Effect of air pollution on peak expiratory flow rate variability.

    PubMed

    Singh, Virendra; Khandelwal, Rakesh; Gupta, A B

    2003-02-01

    Exposure to air pollution affects pulmonary functions adversely. Effect of exposure to pollution on diurnal variation of peak flow was assessed in healthy students. Three hundred healthy age-matched nonsmoker students were studied. They were categorized into two groups on the basis of their residence: commuters and living on campus. Peak expiratory flow (PEF) recordings were made twice daily for 2 days with the Pink City Flow Meter. The measurement was then used to calculate for each subject the amplitude percentage mean, which is an index for expressing PEF variability for epidemiological purposes (Higgins BG, Britton JR, Chinns Jones TD, Jenkinson D, Burnery PG, Tattersfield AE. Distribution of peak expiratory flow variability in a population sample. Am Rev Respir Dis 1989; 140:1368-1372). Air pollution parameters were quantified by measurement of sulfur dioxide (SO2), oxides of nitrogen (NO2), carbon monoxide (CO), and respirable suspended particulate matter (RSPM) in the ambient air at the campus and on the roadside. The mean values of PEF variability (amplitude percent mean) in the students living on campus and in the commuters were 5.7 +/- 3.2 and 11 +/- 3.6, respectively (P < .05). Among the commuters, maximum number of subjects showed amplitude percentage mean PEFR at the higher end of variability distribution, as compared to the students living on campus, among whom the majority of subjects fell in the lower ranges of variability distribution. The ambient air quality parameters, namely SO2, NO2, CO, and RSPM were significantly lower on the campus. It can be concluded that long-term periodic exposure to air pollution can lead to increased PEF variability even in healthy subjects. Measurement of PEF variability may prove to be a simple test to measure effect of air pollution in healthy subjects.

  1. Air quality impacts of European wildfire emissions in a changing climate

    NASA Astrophysics Data System (ADS)

    Knorr, Wolfgang; Dentener, Frank; Hantson, Stijn; Jiang, Leiwen; Klimont, Zbigniew; Arneth, Almut

    2016-05-01

    Wildfires are not only a threat to human property and a vital element of many ecosystems, but also an important source of air pollution. In this study, we first review the available evidence for a past or possible future climate-driven increase in wildfire emissions in Europe. We then introduce an ensemble of model simulations with a coupled wildfire-dynamic-ecosystem model, which we combine with published spatial maps of both wildfire and anthropogenic emissions of several major air pollutants to arrive at air pollutant emission projections for several time slices during the 21st century. The results indicate moderate wildfire-driven emission increases until 2050, but there is a possibility of large increases until the last decades of this century at high levels of climate change. We identify southern and north-eastern Europe as potential areas where wildfires may surpass anthropogenic pollution sources during the summer months. Under a scenario of high levels of climate change (Representative Concentration Pathway, RCP, 8.5), emissions from wildfires in central and northern Portugal and possibly southern Italy and along the west coast of the Balkan peninsula are projected to reach levels that could affect annual mean particulate matter concentrations enough to be relevant for meeting WHO air quality targets.

  2. The effect of inlet air vitiation on combustion efficiency

    SciTech Connect

    Zuomin, F.; Yijun, J.

    1985-01-01

    Experimental results of the effect of inlet air vitiation produced by a vitiating preheater on combustion efficiency of a turbojet combustor and a model ramjet combustor are presented in this paper. An empirical correlation and a calculation method based on stirred reactor theory are derived to correct the vitiation effect. Results obtained by means of these two methods are in good agreement with test data.

  3. Temperature effect on titanium nitride nanometer thin film in air

    NASA Astrophysics Data System (ADS)

    Cen, Z. H.; Xu, B. X.; Hu, J. F.; Ji, R.; Toh, Y. T.; Ye, K. D.; Hu, Y. F.

    2017-02-01

    Titanium nitride (TiN) is a promising alternative plasmonic material to conventional novel metals. For practical plasmonic applications under the influence of air, the temperature-dependent optical properties of TiN thin films in air and its volume variation are essential. Ellipsometric characterizations on a TiN thin film at different increasing temperatures in ambient air were conducted, and optical constants along with film thickness were retrieved. Below 200 °C, the optical properties varied linearly with temperature, in good agreement with other temperature dependent studies of TiN films in vacuum. The thermal expansion coefficient of the TiN thin film was determined to be 10.27  ×  10‑6 °C‑1. At higher temperatures, the TiN thin film gradually loses its metallic characteristics and has weaker optical absorption, impairing its plasmonic performance. In addition, a sharp increase in film thickness was observed at the same time. Changes in the optical properties and film thickness with temperatures above 200 °C were revealed to result from TiN oxidation in air. For the stability of TiN-based plasmonic devices, operation temperatures of lower than 200 °C, or measures to prevent oxidation, are required. The present study is important to fundamental physics and technological applications of TiN thin films.

  4. Effect of isobaric breathing gas shifts from air to heliox mixtures on resolution of air bubbles in lipid and aqueous tissues of recompressed rats.

    PubMed

    Hyldegaard, O; Kerem, D; Melamed, Y

    2011-09-01

    Deep tissue isobaric counterdiffusion that may cause unwanted bubble formation or transient bubble growth has been referred to in theoretical models and demonstrated by intravascular gas formation in animals, when changing inert breathing gas from nitrogen to helium after hyperbaric air breathing. We visually followed the in vivo resolution of extravascular air bubbles injected at 101 kPa into nitrogen supersaturated rat tissues: adipose, spinal white matter, skeletal muscle or tail tendon. Bubbles were observed during isobaric breathing-gas shifts from air to normoxic (80:20) heliox mixture while at 285 kPa or following immediate recompression to either 285 or 405 kPa, breathing 80:20 and 50:50 heliox mixtures. During the isobaric shifts, some bubbles in adipose tissue grew marginally for 10-30 min, subsequently they shrank and disappeared at a rate similar to or faster than during air breathing. No such bubble growth was observed in spinal white matter, skeletal muscle or tendon. In spinal white matter, an immediate breathing gas shift after the hyperbaric air exposure from air to both (80:20) and (50:50) heliox, coincident with recompression to either 285 or 405 kPa, caused consistent shrinkage of all air bubbles, until they disappeared from view. Deep tissue isobaric counterdiffusion may cause some air bubbles to grow transiently in adipose tissue. The effect is marginal and of no clinical consequence. Bubble disappearance rate is faster with heliox breathing mixtures as compared to air. We see no reason for reservations in the use of heliox breathing during treatment of air-diving-induced decompression sickness.

  5. Assessing the changes in the biomechanical properties of the crystalline lens induced by cold cataract with air-pulse OCE

    NASA Astrophysics Data System (ADS)

    Wu, C.; Singh, M.; Liu, C.-H.; Han, Z.; Li, J.; Raghunathan, R.; Larin, K. V.

    2015-11-01

    A cataract is the increase in opacity of the crystalline lens that can pathologically degrade visual acuity. In this study, we utilized a phase-sensitive optical coherence elastography (OCE) system to study the effects of a cold cataract on the biomechanical properties of the porcine crystalline lens in vitro. The cold cataract was induced by placing the whole lens in a low temperature environment until the lens was obviously clouded. Air-pulse OCE measurements were conducted on 6 lenses before and after cold cataract induction. A low amplitude displacement (≤ 10 µm) was induced by a focused air-pulse and the temporal deformation profiles from the surface and within the lenses were analyzed. The results demonstrated that the stiffness of the porcine lens increased after induction of the cold cataract, and it demonstrated the feasibility of OCE to assess the biomechanical changes in the lens due to cataract.

  6. The effect of body postures on the distribution of air gap thickness and contact area.

    PubMed

    Mert, Emel; Psikuta, Agnes; Bueno, Marie-Ange; Rossi, René M

    2017-02-01

    The heat and mass transfer in clothing is predominantly dependent on the thickness of air layer and the magnitude of contact area between the body and the garment. The air gap thickness and magnitude of the contact area can be affected by the posture of the human body. Therefore, in this study, the distribution of the air gap and the contact area were investigated for different body postures of a flexible manikin. In addition, the effect of the garment fit (regular and loose) and style (t-shirts, sweatpants, jacket and trousers) were analysed for the interaction between the body postures and the garment properties. A flexible manikin was scanned using a three-dimensional (3D) body scanning technique, and the scans were post-processed in dedicated software. The body posture had a strong effect on the air gap thickness and the contact area for regions where the garment had a certain distance from the body. Furthermore, a mathematical model was proposed to estimate the possible heat transfer coefficient for the observed air layers and their change with posture. The outcome of this study can be used to improve the design of the protective and functional garments and predict their effect on the human body.

  7. The effect of body postures on the distribution of air gap thickness and contact area

    NASA Astrophysics Data System (ADS)

    Mert, Emel; Psikuta, Agnes; Bueno, Marie-Ange; Rossi, René M.

    2017-02-01

    The heat and mass transfer in clothing is predominantly dependent on the thickness of air layer and the magnitude of contact area between the body and the garment. The air gap thickness and magnitude of the contact area can be affected by the posture of the human body. Therefore, in this study, the distribution of the air gap and the contact area were investigated for different body postures of a flexible manikin. In addition, the effect of the garment fit (regular and loose) and style (t-shirts, sweatpants, jacket and trousers) were analysed for the interaction between the body postures and the garment properties. A flexible manikin was scanned using a three-dimensional (3D) body scanning technique, and the scans were post-processed in dedicated software. The body posture had a strong effect on the air gap thickness and the contact area for regions where the garment had a certain distance from the body. Furthermore, a mathematical model was proposed to estimate the possible heat transfer coefficient for the observed air layers and their change with posture. The outcome of this study can be used to improve the design of the protective and functional garments and predict their effect on the human body.

  8. Effect of plateout, air motion and dust removal on radon decay product concentration in a simulated residence.

    PubMed

    Rudnick, S N; Hinds, W C; Maher, E F; First, M W

    1983-08-01

    The effectiveness of increased air motion and dust removal in reducing radon decay product concentration in residences subject to radon intrusion was evaluated in a 78-m3 room under steady-state conditions for air infiltration rates between 0.2 and 0.9 air changes per hour. Room-size, portable electrostatic precipitators and high-efficiency fibrous filters were tested as typical residential air cleaning devices; a portable box fan and a ceiling fan were employed as typical residential air movers. Reductions in working levels of 40-90% were found. The fate of radon decay products, with and without mixing fans, was determined by direct measurement. When mixing fans were used, most of the nonairborne potential alpha-energy was plated out on the room surfaces; less than 10% was deposited on the fan blades or housing. Results were compared to a mathematical model based on well-mixed room air, and good agreement was obtained.

  9. Close correlation between global air temperature change and polar motion during 1962-2013

    NASA Astrophysics Data System (ADS)

    Huang, Mei; Zhu, Lin; Gong, He; Shao, Yaping

    2016-10-01

    Polar motion is an important Earth orientation parameter, but our understanding of its relation to global climate change is highly uncertain. In this study, we examine the links between polar motion excitation and annual mean air temperature during the period of 1962-2013 and discuss the possible responsible mechanisms. The regions of positive correlation correspond well with the warming centers. Spectral analysis shows that they have strong signals at similar frequencies. Strong correlations are also found between the polar motion and surface air pressure and vertical integrated zonal wind. This implies that polar motion serves as an important indicator of global climate change, and thus, the feedbacks between the solid Earth and the climate system deserve careful considerations.

  10. Ozone and Trace Gas Trends in the UK and Links to Changing Air Mass Pathways

    NASA Astrophysics Data System (ADS)

    Fleming, Z.; Monks, P. S.; Reeves, C.; Bohnenstengel, S.

    2014-12-01

    Trace gas measurements from UK measurement sites on the North Sea coast and in central London reveal a complicated relationship between NO2, CO, hydrocarbons and ozone. Due to the location of the sites, they receive air masses from the UK, Europe, the North sea, Scandinavia and the Arctic and Atlantic Seas and any seasonality is hard to discern. The transport pathway of air masses that can change on an hourly timescale clearly influences the trace gas levels. Investigations into how the transport pathways have changed over the years, using the NAME dispersion model try to elucidate whether it is the 'where' (transport pathway) or the 'what' (trace gas emissions) that is leading to the ozone trends recorded over the past few years.

  11. Winter sports athletes: long-term effects of cold air exposure.

    PubMed

    Sue-Chu, Malcolm

    2012-05-01

    Athletes such as skaters and skiers inhale large volumes of cold air during exercise and shift from nasal to mouth breathing. Endurance athletes, like cross-country skiers, perform at 80% or more of their maximal oxygen consumption and have minute ventilations in excess of 100 l/min. Cold air is always dry, and endurance exercise results in loss of water and heat from the lower respiratory tract. In addition, athletes can be exposed to indoor and outdoor pollutants during the competitive season and during all-year training. Hyperpnoea with cold dry air represents a significant environmental stress to the airways. Winter athletes have a high prevalence of respiratory symptoms and airway hyper-responsiveness to methacholine and hyperpnoea. The acute effects of exercise in cold air are neutrophil influx as demonstrated in lavage fluid and airway epithelial damage as demonstrated by bronchoscopy. Upregulation of pro-inflammatory cytokines has been observed in horses. Chronic endurance training damages the epithelium of the small airways in mice. Airway inflammation has been observed on bronchoscopy of cross-country skiers and in dogs after a 1100-mile endurance race in Alaska. Neutrophilic and lymphocytic inflammation with remodelling is present in bronchial biopsies from skiers. Repeated peripheral airway hyperpnoea with dry air causes inflammation and remodelling in dogs. As it is currently unknown if these airway changes are reversible upon cessation of exposure, preventive measures to diminish exposure of the lower airways to cold air should be instituted by all winter sports athletes.

  12. A proxy analysis of urban air quality hazards in Bergen, Norway under a changing climate.

    NASA Astrophysics Data System (ADS)

    Wolf, Tobias; Esau, Igor; Reuder, Joachim

    2014-05-01

    The urban air quality in Bergen, Norway is characterized by clean air throughout most of the year interrupted by short episodes of hazardous pollution levels especially in close proximity to major road-emission sources. These pollution episodes are linked to winter time anti-cyclonic weather conditions with persistent stable temperature stratification (inversions) in the Atmospheric Boundary Layer. Although the pollution episodes are local events, the high pollution episodes are linked to large-scale persistent blockings in the atmospheric circulation. Here we present an atmospheric circulation proxy for the pollution episodes based on the ECMWF ERA-Interim reanalysis. The proxy is based on local 3-hourly instantaneous wind-speeds and directions at the 1000 hPa pressure level, and 1-day running mean temperature deviations at 2 m above ground from the 1-day running mean temperatures averaged over the full ERA-Interim record length. We tuned the thresholds for each quantity to the occurrence of events with an hourly mean NO2 concentration > 150 μg/m3 at a high pollution reference station. A condition on cloud cover had only little effect, sea-level pressure was not applicable. High pollution episodes predicted during typical low traffic days (Sundays, Christmas, New Year) were removed. The final proxy had a detection rate of 82 %, a false alarm rate of 77 % and a correct null prediction rate of 96 %. The high false alarm rate was expected because of the relaxed thresholds chosen in order to include a large fraction of possible states of atmospheric circulation that lead to hazardous air quality. Additionally, the false alarm rate was high because no constraint on the persistence of adverse meteorological conditions was set and because of the high variability of traffic, not always leading to hazardous pollution levels, even if the atmospheric circulation would allow for it. The Scandinavian index, an often used proxy for the occurrence of atmospheric circulation

  13. Changes in Foliar Chemistry Along a Midwestern Air Pollution Gradient: 1988- 2005

    NASA Astrophysics Data System (ADS)

    Talhelm, A. F.; Burton, A. J.; Pregitzer, K. S.

    2008-12-01

    Sugar maple (Acer saccharum) leaf litter has been collected annually for the past two decades from four sites in Michigan along a regional gradient in air pollution. During this time, wet acid deposition at monitoring stations near these sites declined 20-30 % while wet deposition of nitrogen remained virtually unchanged. Given these dynamics, we examined the foliar chemistry of this leaf litter to determine (a) if concentrations of the biologically important elements Ca and Al had responded to the reduction in acid deposition and (b) if foliar N concentrations and δ15N values reflected a trend toward increased N availability resulting from the persistence of high rates of N deposition. During the study period of 1988-2005, the foliar [Ca] declined significantly at three of the four sites and the foliar [Al] declined significantly at all four sites. Together, these changes suggest that amount of these elements removed from exchange sites and put into soil solution has decreased with the decline in acid deposition. Furthermore, the ratio of Ca:Al significantly increased at each site. Changes in the Ca:Al are of particular importance because low Ca to Al ratios in foliar tissue have been strongly implicated in declines in plant growth resulting from acid deposition. The increase in the foliar Ca:Al suggests that rather than causing a lasting depletion of base cations, previous highs in acid deposition had a transient effect from which hardwood forests in this region have largely recovered. In contrast, there were no significant trends in the [N] at any of the four sites and only one site in the middle of the pollution gradient showed a significant trend in δ15N that implies increased N availability. These results suggest that current levels of N deposition are not causing widespread increases in the amount of N available to plants in these ecosystems and do not appear to be quickly pushing the systems toward N saturation.

  14. Final Environmental Assessment for Force Structure Changes at Langley Air Force Base, VA

    DTIC Science & Technology

    2011-10-01

    Shepard Blvd, Hampton, VA, 23665, DEQ PC No. 20095002, PC Case Status - Release Confirmed, Case Closed. Langley Air Force Base- Building 333, 90 Oak...NOISEXPO ‘77, Chicago , IL. March. White, R. 1972. Effects of Repetitive Sonic Booms on Glass Breakage. FAA Report FAA-RD-72- 43. April. 6

  15. New Directions: Understanding Interactions of Air Quality and Climate Change at Regional Scales

    EPA Science Inventory

    The estimates of the short-lived climate forcers’ (SLCFs) impacts and mitigation effects on the radiation balance have large uncertainty because the current global model set-ups and simulations contain simplified parameterizations and do not completely cover the full range of air...

  16. Implementation of Organizational Change in the Air Force: a Case Study

    DTIC Science & Technology

    1989-09-01

    30 What are the Primary Missions of the LOC (MM)?.......................... 31 What Is the Mission of Your Part In the organization...procedures for the Air Logistics Centers (ALCs) and the Major Commands (MAJCOMS). The primary function of the LOC is to provide weapon system guidance and...innovative company. Key to their success is a wholistic approach to change, with an emphasis on people. In an article about outstanding companies

  17. Measured Air Distribution Effectiveness for Residential Mechanical Ventilation Systems

    SciTech Connect

    Sherman, Max; Sherman, Max H.; Walker, Iain S.

    2008-05-01

    The purpose of ventilation is dilute or remove indoor contaminants that an occupant is exposed to. In a multi-zone environment such as a house, there will be different dilution rates and different source strengths in every zone. Most US homes have central HVAC systems, which tend to mix the air thus the indoor conditions between zones. Different types of ventilation systems will provide different amounts of exposure depending on the effectiveness of their air distribution systems and the location of sources and occupants. This paper will report on field measurements using a unique multi-tracer measurement system that has the capacity to measure not only the flow of outdoor air to each zone, but zone-to-zone transport. The paper will derive seven different metrics for the evaluation of air distribution. Measured data from two homes with different levels of natural infiltration will be used to evaluate these metrics for three different ASHRAE Standard 62.2 compliant ventilation systems. Such information can be used to determine the effectiveness of different systems so that appropriate adjustments can be made in residential ventilation standards such as ASHRAE Standard 62.2.

  18. Health effects of SRS non-radiological air emissions

    SciTech Connect

    Stewart, J.

    1997-06-16

    This report examines the potential health effects of non radiological emissions to the air resulting from operations at the Savannah River Site (SRS). The scope of this study was limited to the 55 air contaminants for which the US Environmental Protection Agency (EPA) has quantified risk by determining unit risk factors (excess cancer risks) and/or reference concentrations (deleterious non cancer risks). Potential health impacts have been assessed in relation to the maximally exposed individual. This is a hypothetical person who resides for a lifetime at the SRS boundary. The most recent (1994) quality assured SRS emissions data available were used. Estimated maximum site boundary concentrations of the air contaminants were calculated using air dispersion modeling and 24-hour and annual averaging times. For the emissions studied, the excess cancer risk was found to be less than the generally accepted risk level of 1 in 100,000 and, in most cases, was less than 1 in 1,000,000. Deleterious non cancer effects were also found to be very unlikely.

  19. Use of a mobile laboratory to evaluate changes in on-road air pollutants during the Beijing 2008 Summer Olympics

    NASA Astrophysics Data System (ADS)

    Wang, M.; Zhu, T.; Zheng, J.; Zhang, R. Y.; Zhang, S. Q.; Xie, X. X.; Han, Y. Q.; Li, Y.

    2009-11-01

    China implemented systematic air pollution control measures during the 2008 Beijing Summer Olympics and Paralympics to improve air quality. This study used a versatile mobile laboratory to conduct in situ monitoring of on-road air pollutants along Beijing's Fourth Ring Road on 31 selected days before, during, and after the Olympics air pollution control period. A suite of instruments with response times of less than 30 s was used to measure temporal and spatial variations in traffic-related air pollutants, including NOx, CO, PM1.0 surface area (S(PM1)), black carbon (BC), and benzene, toluene, the sum of ethylbenzene, and m-, p-, and o-xylene (BTEX). During the Olympics (8-23 August, 2008), on-road air pollutant concentrations decreased significantly, by up to 54% for CO, 41% for NOx, 70% for SO2, 66% for BTEX, 12% for BC, and 18% for SPM1, compared with the pre-control period (before 20 July). Concentrations increased again after the control period ended (after 20 September), with average increases of 33% for CO, 42% for NOx, 60% for SO2, 40% for BTEX, 26% for BC, and 37% for S(PM1), relative to the control period. Variations in pollutants concentrations were correlated with changes in traffic speed and the number and types of vehicles on the road. Throughout the measurement periods, the concentrations of NOx, CO, and BTEX varied markedly with the numbers of light- and medium-duty vehicles (LDVs and MDVs, respectively) on the road. Only after 8 August was a noticeable relationship found between BC and S(PM1) and the number of heavy-duty vehicles (HDVs). Additionally, BC and S(PM1) showed a strong correlation with SO2 before the Olympics, indicating possible industrial sources from local emissions as well as regional transport activities in the Beijing area. Such factors were identified in measurements conducted on 6 August in an area southwest of Beijing. The ratio of benzene to toluene, a good indicator of traffic emissions, shifted suddenly from about 0

  20. Use of a mobile laboratory to evaluate changes in on-road air pollutants during the Beijing 2008 Summer Olympics

    NASA Astrophysics Data System (ADS)

    Wang, M.; Zhu, T.; Zheng, J.; Zhang, R. Y.; Zhang, S. Q.; Xie, X. X.; Han, Y. Q.; Li, Y.

    2009-06-01

    China implemented systematic air pollution control measures during the 2008 Beijing Summer Olympics and Paralympics to improve air quality. This study used an innovative mobile laboratory to conduct in situ monitoring of on-road air pollutants along Beijing's 4th Ring Road on 31 selected days before, during, and after the Olympics air pollution control period. A suite of instruments with response times of less than 30 s was used to measure temporal and spatial variations in traffic-related air pollutants, including NOx, CO, PM1.0 surface area (SPM1), black carbon (BC), and benzene, toluene, ethylbenzene, and m-, p-, and o-xylene (BTEX). During the Olympics (8-23 August 2008), on-road air pollutant concentrations decreased significantly by up to 54% for CO, 41% for NOx, 70% for SO2, 66% for BTEX, 12% for BC, and 18% for SPM1 compared to the pre-control period (before 20 July). Concentrations increased again after the control period ended (after 20 September), with average increases of 33% for CO, 42% for NOx, 60% for SO2, 40% for BTEX, 26% for BC, and 37% for SPM1. Variations in pollutants concentrations were correlated with changes in traffic speed and the number and types of vehicles on the road. Throughout the measurement periods, the concentrations of NOx, CO, and BTEX varied markedly with the numbers of light- and medium-duty vehicles (LDVs and MDVs, respectively) on the road. Only after 8 August was a noticeable relationship between BC and SPM1 and the number of heavy-duty vehicles (HDVs) found. Additionally, BC and SPM1 showed a strong correlation with SO2 before the Olympics, indicating possible industrial sources from local emissions as well as regional transport activities in the Beijing area. Such factors were identified in measurements conducted on 6 August in an area southwest of Beijing. The ratio of benzene to toluene, a good indicator of traffic emissions, shifted suddenly from about 0.26 before the Olympics to approximately 0.48 after the Olympics

  1. Rebuilding the Joint Airborne Forward Air Controller: Analyzing Joint Air Tasking Doctrine’s Ability to Facilitate Effective Air-Ground Integration

    DTIC Science & Technology

    2013-12-13

    Joint Training Directive LNO Liaison Officer MAAP Master Air Attack Plan MACCS Marine Air Command and Control System MACV Military Assistance...needed in creating a common understanding of force employment concepts, establishing effective information networks and joint communications systems , and...

  2. The effects of air pollution regulations on the US refining industry. Task 3

    SciTech Connect

    Not Available

    1989-06-01

    Numerous air pollution regulations affecting petroleum refineries recently have been promulgated, have been proposed, or are under consideration at the federal, state, and local level. As shown in Figure ES-1, all of these environmental regulations are intended to take effect over the relatively short time period from 1989 through 1995. In the aggregate these regulatory activities have significant implications for the US refining industry and the Nation, including: Major investment requirements; changes in industry profitability; potential closure of some refineries; and potential changes in crude oil or product import dependence. At issue is whether the cumulative effect of these regulations could so adversely affect the US refining industry that US national security would be affected. In addition to the regulations outlined in Figure ES-1, President Bush recently presented a major new plan to improve the nation`s air quality. The aspects of the President`s plan that could strongly affect US refineries are summarized below.

  3. Effect of air pollution on athlete health and performance.

    PubMed

    Rundell, Kenneth William

    2012-05-01

    Unfavourable effects on the respiratory and the cardiovascular systems from short-term and long-term inhalation of air pollution are well documented. Exposure to freshly generated mixed combustion emissions such as those observed in proximity to roadways with high volumes of traffic and those from ice-resurfacing equipment are of particular concern. This is because there is a greater toxicity from freshly generated whole exhaust than from its component parts. The particles released from emissions are considered to cause oxidative damage and inflammation in the airways and the vascular system, and may be related to decreased exercise performance. However, few studies have examined this aspect. Several papers describe deleterious effects on health from chronic and acute air pollution exposure. However, there has been no research into the effects of long-term exposure to air pollution on athletic performance and a paucity of studies that describe the effects of acute exposure on exercise performance. The current knowledge of exercising in the high-pollution environment and the consequences that it may have on athlete performance are reviewed.

  4. Effects of climate change on Arctic marine mammal health.

    PubMed

    Burek, Kathy A; Gulland, Frances M D; O'Hara, Todd M

    2008-03-01

    The lack of integrated long-term data on health, diseases, and toxicant effects in Arctic marine mammals severely limits our ability to predict the effects of climate change on marine mammal health. The overall health of an individual animal is the result of complex interactions among immune status, body condition, pathogens and their pathogenicity, toxicant exposure, and the various environmental conditions that interact with these factors. Climate change could affect these interactions in several ways. There may be direct effects of loss of the sea ice habitat, elevations of water and air temperature, and increased occurrence of severe weather. Some of the indirect effects of climate change on animal health will likely include alterations in pathogen transmission due to a variety of factors, effects on body condition due to shifts in the prey base/food web, changes in toxicant exposures, and factors associated with increased human habitation in the Arctic (e.g., chemical and pathogen pollution in the runoff due to human and domestic-animal wastes and chemicals and increased ship traffic with the attendant increased risks of ship strike, oil spills, ballast pollution, and possibly acoustic injury). The extent to which climate change will impact marine mammal health will also vary among species, with some species more sensitive to these factors than others. Baseline data on marine mammal health parameters along with matched data on the population and climate change trends are needed to document these changes.

  5. Effects of cold dry air nasal stimulation on airway mucosal blood flow in humans.

    PubMed

    Le Merre, C; Isber, J; Chediak, A D; Wanner, A

    2003-10-01

    Several studies have demonstrated that nasal challenges can induce reflex responses in the respiratory system. Some authors have described bronchoconstriction and modification of the pattern of breathing following nasal challenges by irritants and cold air. We propose to determine the effect of nasal stimulation with cold dry air on airway mucosal blood flow (Qaw) in the proximal tracheal bronchial tree of healthy humans. Nine healthy subjects participated in the study. Baseline measurement Qaw, nasal airway resistance (NAR) and airway caliber by specific airways conductance (SGaw) were followed by nasal challenge with cold dry air. Qaw, NAR and Sgaw were determined after the challenge. In those subjects in which a significant decline in Qaw was recorded the protocol was repeated after pretreatment with nasal anesthesia using topical lidocaine. Cold dry air challenge produced a significant decrease in mean Qaw for the nine subjects and this response was abolished by pretreatment with nasal anesthesia using topical lidocaine. There was no significant change in Sgaw and NAR after the challenge and topical lidocaine anesthesia. Our data indicates that nasal stimulation with cold dry air leads to a reduction in Qaw and that this effect may be mediated by a nasal reflex.

  6. Cross influences of ozone and sulfate precursor emissions changes on air quality and climate.

    PubMed

    Unger, Nadine; Shindell, Drew T; Koch, Dorothy M; Streets, David G

    2006-03-21

    Tropospheric O(3) and sulfate both contribute to air pollution and climate forcing. There is a growing realization that air quality and climate change issues are strongly connected. To date, the importance of the coupling between O(3) and sulfate has not been fully appreciated, and thus regulations treat each pollutant separately. We show that emissions of O(3) precursors can dramatically affect regional sulfate air quality and climate forcing. At 2030 in an A1B future, increased O(3) precursor emissions enhance surface sulfate over India and China by up to 20% because of increased levels of OH and gas-phase SO(2) oxidation rates and add up to 20% to the direct sulfate forcing for that region relative to the present day. Hence, O(3) precursors impose an indirect forcing via sulfate, which is more than twice the direct O(3) forcing itself (compare -0.61 vs. +0.35 W/m(2)). Regulatory policy should consider both air quality and climate and should address O(3) and sulfate simultaneously because of the strong interaction between these species.

  7. Product lifetime, energy efficiency and climate change: A case study of air conditioners in Japan.

    PubMed

    Nishijima, Daisuke

    2016-10-01

    This study proposed a modelling technique for estimating life-cycle CO2 emissions of durable goods by considering changes in product lifetime and energy efficiency. The stock and flow of durable goods was modelled by Weibull lifetime distributions and the trend in annual energy efficiency (i.e., annual electricity consumption) of an "average" durable good was formulated as a reverse logistic curve including a technologically critical value (i.e., limit energy efficiency) with respect to time. I found that when the average product lifetime is reduced, there is a trade-off between the reduction in emissions during product use (use phase), due to the additional purchases of new, more energy-efficient air conditioners, and the increase in emissions arising from the additional production of new air conditioners stimulated by the reduction of the average product lifetime. A scenario analysis focused on residential air conditioners in Japan during 1972-2013 showed that for a reduction of average lifetime of 1 year, if the air conditioner energy efficiency limit can be improved by 1.4% from the estimated current efficiency level, then CO2 emissions can be reduced by approximately the same amount as for an extension of average product lifetime of 1 year.

  8. Effect of low emission sources on air quality in Cracow

    SciTech Connect

    Nedoma, J.

    1995-12-31

    The paper presents calculation of power engineering low emission and results of stimulation of the effect of this emission on air quality in Cracow, Poland. It has been stated that the segment of low emission in central areas of the town makes up ca. 40% of the observed concentration of sulfur dioxide. Furthermore it has been stated that the capital investment must be concentrated in the central part of the town in order to reach noticeable improvement of air quality in Cracow. Neither the output of a separate power source nor the emission level and its individual harmful effect, but the location of the source and especially packing density of the sources must decide the priority of upgrading actions.

  9. Geomagnetic Field Effects on the Imaging Air Shower Cherenkov Technique

    NASA Astrophysics Data System (ADS)

    Commichau, S.C.; Biland, A.; Kranich, D.; de los Reyes, R.; Moralejo, A.; Sobczyńska, D.

    Imaging Air Cherenkov Telescopes (IACTs) detect the Cherenkov light flashes of Extended Air Showers (EAS) triggered by VHE gamma-rays impinging on the Earth's atmosphere. Due to the overwhelming background from hadron induced EAS, the discrimination of the rare gamma-like events is rather difficult, in particular at energies below 100 GeV. The influence of the Geomagnetic Field (GF) on the EAS development can further complicate this discrimination and, in addition, also systematically affect the gamma-efficiency and energy resolution of an IACT. Here we present the results from dedicated Monte Carlo (MC) simulations for the MAGIC telescope site, show the GF effects on real data as well as possible corrections for these effects.

  10. Ozone changes under solar geoengineering: implications for UV exposure and air quality

    NASA Astrophysics Data System (ADS)

    Nowack, P. J.; Abraham, N. L.; Braesicke, P.; Pyle, J. A.

    2015-11-01

    Various forms of geoengineering have been proposed to counter anthropogenic climate change. Methods which aim to modify the Earth's energy balance by reducing insolation are often subsumed under the term Solar Radiation Management (SRM). Here, we present results of a standard SRM modelling experiment in which the incoming solar irradiance is reduced to offset the global mean warming induced by a quadrupling of atmospheric carbon dioxide. For the first time in an atmosphere-ocean coupled climate model, we include atmospheric composition feedbacks such as ozone changes under this scenario. Including the composition changes, we find large reductions in surface UV-B irradiance, with implications for vitamin D production, and increases in surface ozone concentrations, both of which could be important for human health. We highlight that both tropospheric and stratospheric ozone changes should be considered in the assessment of any SRM scheme, due to their important roles in regulating UV exposure and air quality.

  11. Effectiveness of national air pollution control policies on the air quality in metropolitan areas of China.

    PubMed

    Wang, Shuxiao; Xing, Jia; Zhao, Bin; Jang, Carey; Hao, Jiming

    2014-01-01

    Understanding the effectiveness of national air pollution controls is important for control policy design to improve the future air quality in China. This study evaluated the effectiveness of major national control policies implemented recently in China through a modeling analysis. The sulfur dioxide (SO2) control policy during the 11th Five Year Plan period (2006-2010) had succeeded in reducing the national SO2 emission in 2010 by 14% from its 2005 level, which correspondingly reduced ambient SO2 and sulfate (SO4(2-)) concentrations by 13%-15% and 8%-10% respectively over east China. The nitrogen oxides (NO(x)) control policy during the 12th Five Year Plan period (2011-2015) targets the reduction of the national NO(x) emission in 2015 by 10% on the basis of 2010. The simulation results suggest that such a reduction in NO(x) emission will reduce the ambient nitrogen dioxide (NO2), nitrate (NO3(-)), 1-hr maxima ozone (O3) concentrations and total nitrogen deposition by 8%, 3%-14%, 2% and 2%-4%, respectively over east China. The application of new emission standards for power plants will further reduce the NO2, NO3(-), 1-hr maxima O(3 concentrations and total nitrogen deposition by 2%-4%, 1%-6%, 0-2% and 1%-2%, respectively. Sensitivity analysis was conducted to evaluate the inter-provincial impacts of emission reduction in Beijing-Tianjin-Hebei and the Yangtze River Delta, which indicated the need to implement joint regional air pollution control.

  12. Respiratory health effects of ambient air pollution: an update.

    PubMed

    Sava, Francesco; Carlsten, Chris

    2012-12-01

    There is new evidence for ambient air pollution (AAP) leading to an increased incidence of respiratory diseases in adults. Research has demonstrated that co-exposures have the potential to dramatically augment the effects of AAP and lower the threshold of effect of a given pollutant. Interactions between genes related to oxidative stress and AAP seem to significantly alter the effect of AAP on an individual and population basis. A better definition of vulnerable populations may bolster local or regional efforts to remediate AAP. Advances in genetic research tools have the potential to identify candidate genes that can guide further research.

  13. Extended effects of air pollution on cardiopulmonary mortality in Vienna

    NASA Astrophysics Data System (ADS)

    Neuberger, Manfred; Rabczenko, Daniel; Moshammer, Hanns

    BackgroundCurrent standards for fine particulates and nitrogen dioxide are under revision. Patients with cardiovascular disease have been identified as the largest group which need to be protected from effects of urban air pollution. MethodsWe sought to estimate associations between indicators of urban air pollution and daily mortality using time series of daily TSP, PM 10, PM 2.5, NO 2, SO 2, O 3 and nontrauma deaths in Vienna (Austria) 2000-2004. We used polynomial distributed lag analysis adjusted for seasonality, daily temperature, relative humidity, atmospheric pressure and incidence of influenza as registered by sentinels. ResultsAll three particulate measures and NO 2 were associated with mortality from all causes and from ischemic heart disease and COPD at all ages and in the elderly. The magnitude of the effect was largest for PM 2.5 and NO 2. Best predictor of mortality increase lagged 0-7 days was PM 2.5 (for ischemic heart disease and COPD) and NO 2 (for other heart disease and all causes). Total mortality increase, lagged 0-14 days, per 10 μg m -3 was 2.6% for PM 2.5 and 2.9% for NO 2, mainly due to cardiopulmonary and cerebrovascular causes. ConclusionAcute and subacute lethal effects of urban air pollution are predicted by PM 2.5 and NO 2 increase even at relatively low levels of these pollutants. This is consistent with results on hospital admissions and the lack of a threshold. While harvesting (reduction of mortality after short increase due to premature deaths of most sensitive persons) seems to be of minor importance, deaths accumulate during 14 days after an increase of air pollutants. The limit values for PM 2.5 and NO 2 proposed for 2010 in the European Union are unable to prevent serious health effects.

  14. Metropolitan New York in the greenhouse: Air quality and health effects

    SciTech Connect

    Kleinman, L.I.; Lipfert, F.

    1996-01-01

    A variety of potential effects on human health resulting from climate change have been identified in several assessments. According to an international panel{sup 1} they include direct effects of extreme temperatures on cardiovascular deaths, secondary effects due to vector-borne diseases or crop yields, and tertiary effects such as those that might arise from conflicts over freshwater supplies. To this fist we add the secondary effects of increased air pollution, which may result either directly from climate change or indirectly from increased air conditioning loads and the corresponding pollutant emissions from electric utilities. Higher ozone concentrations have been linked to increased ambient temperatures by both theory and observations of monitoring data. A similar association with particulate matter has been limited to observations, thus far. The pollution-heat linkage has been recognized before` but health effects have not been evaluated in terms of predictions of the joint effects of both agents. This paper has been prepared in two sections. First, we discuss the ozone situation with special reference to the Northeast Corridor and New York. In the second section, we present estimates of the health effects of climate change on New York and discuss some mitigation options.

  15. Air pollution induced changes in the photosynthetic pigments of selected plant species.

    PubMed

    Joshi, P C; Swami, Abhishek

    2009-03-01

    Changes in the concentration of different photosynthetic pigments (Chlorophyll and carotenoids) were determined in the leaves of six tree species exposed to air pollution due to vehicular emissions. The six tree species, which are all economically important because of their being fruit bearers, used for timber fodder and as road side trees on the basis of their air pollution tolerance index. These included Mangifera indica L., Tectona grandis Linn.f , Shorea robusta Gaertn.f., Holoptelea integrifolia (Roxb.) Planch, Eucalyptus citridora Hook. Syn. and Mallotus philippinensis Muell-Arg. Reduction in chlorophyll 'a', 'b' and carotenoid was recorded in the leaf samples collected from polluted areas when compared with samples from control areas. The highest reduction in total chlorophyll was observed in Holoptelea integrifolia (Roxb.) (48.73%) Planch whereas, the lowest reduction (17.84 %) was recorded in Mallotus philippinensis Muell-Arg. Similarly in case of carotenoid contents, highest reduction (43.02%) was observed in Eucalyptus citridora, and lowest in Mallotus philippinensis Muell-Arg (19.31%). The data obtained were further analyzed using one-way ANOVA and a significant change was recorded in the studied parameters. These studies clearly indicate that the vehicular induced air pollution reduces the concentration of photosynthetic pigments in the trees exposed to road side pollution.

  16. Impacts of Future Climate and Emission Changes on U.S. Air Quality

    SciTech Connect

    Penrod, Ashley; Zhang, Yang; Wang, K.; Wu, Shiang Yuh; Leung, Lai-Yung R.

    2014-06-01

    Changes in climate and emissions will affect future air quality. In this work, simulations of present (2001-2005) and future (2026-2030) regional air quality are conducted with the newly released CMAQ version 5.0 to examine the individual and combined impacts of simulated future climate and anthropogenic emission projections on air quality over the U.S. Current (2001-2005) meteorological and chemical predictions are evaluated against observational data to assess the model’s capability in reproducing the seasonal differences. Overall, WRF and CMAQ perform reasonably well. Increased temperatures (up to 3.18 °C) and decreased ventilation (up to 157 m in planetary boundary layer height) are found in both future winter and summer, with more prominent changes in winter. Increases in future temperatures result in increased isoprene and terpene emissions in winter and summer, driving the increase in maximum 8-h average O3 (up to 5.0 ppb) over the eastern U.S. in winter while decreases in NOx emissions drive the decrease in O3 over most of the U.S. in summer. Future concentrations of PM2.5 in winter and summer and many of its components including organic matter in winter, ammonium and nitrate in summer, and sulfate in winter and summer, decrease due to decreases in primary anthropogenic emissions and the concentrations of secondary anthropogenic pollutants and increased precipitation in winter. Future winter and summer dry and wet deposition fluxes are spatially variable and increase with increasing surface resistance and precipitation (e.g., NH4+ and NO3- dry and wet deposition fluxes increase in winter over much of the U.S.), respectively, and decrease with a decrease in ambient particulate concentrations (e.g., SO42- dry and wet deposition fluxes decrease over the eastern U.S. in summer and winter). Sensitivity simulations show that anthropogenic emission projections dominate over changes in climate in their impacts on the U.S. air quality in the near future. Changes

  17. Power Reduction of the Air-Breathing Hall-Effect Thruster

    NASA Astrophysics Data System (ADS)

    Kim, Sungrae

    Electric propulsion system is spotlighted as the next generation space propulsion system due to its benefits; one of them is specific impulse. While there are a lot of types in electric propulsion system, Hall-Effect Thruster, one of electric propulsion system, has higher thrust-to-power ratio and requires fewer power supplies for operation in comparison to other electric propulsion systems, which means it is optimal for long space voyage. The usual propellant for Hall-Effect Thruster is Xenon and it is used to be stored in the tank, which may increase the weight of the thruster. Therefore, one theory that uses the ambient air as a propellant has been proposed and it is introduced as Air-Breathing Hall-Effect Thruster. Referring to the analysis on Air-Breathing Hall-Effect Thruster, the goal of this paper is to reduce the power of the thruster so that it can be applied to real mission such as satellite orbit adjustment. To reduce the power of the thruster, two assumptions are considered. First one is changing the altitude for the operation, while another one is assuming the alpha value that is electron density to ambient air density. With assumptions above, the analysis was done and the results are represented. The power could be decreased to 10s˜1000s with the assumptions. However, some parameters that do not satisfy the expectation, which would be the question for future work, and it will be introduced at the end of the thesis.

  18. Estimating causal effects of air quality regulations using principal stratification for spatially correlated multivariate intermediate outcomes.

    PubMed

    Zigler, Corwin M; Dominici, Francesca; Wang, Yun

    2012-04-01

    Methods for causal inference regarding health effects of air quality regulations are met with unique challenges because (1) changes in air quality are intermediates on the causal pathway between regulation and health, (2) regulations typically affect multiple pollutants on the causal pathway towards health, and (3) regulating a given location can affect pollution at other locations, that is, there is interference between observations. We propose a principal stratification method designed to examine causal effects of a regulation on health that are and are not associated with causal effects of the regulation on air quality. A novel feature of our approach is the accommodation of a continuously scaled multivariate intermediate response vector representing multiple pollutants. Furthermore, we use a spatial hierarchical model for potential pollution concentrations and ultimately use estimates from this model to assess validity of assumptions regarding interference. We apply our method to estimate causal effects of the 1990 Clean Air Act Amendments among approximately 7 million Medicare enrollees living within 6 miles of a pollution monitor.

  19. Evaluating the Contribution of Natural Variability and Climate Model Response to Uncertainty in Projections of Climate Change Impacts on U.S. Air Quality

    EPA Science Inventory

    We examine the effects of internal variability and model response in projections of climate impacts on U.S. ground-level ozone across the 21st century using integrated global system modeling and global atmospheric chemistry simulations. The impact of climate change on air polluti...

  20. Changes in the frequency of extreme air pollution events over the Eastern United States and Europe

    NASA Astrophysics Data System (ADS)

    Rieder, H. E.; Fiore, A. M.; Fang, Y.; Staehelin, J.

    2011-12-01

    Over the past few decades, thresholds for national air quality standards, intended to protect public health and welfare, have been lowered repeatedly. At the same time observations, over Europe and the Eastern U.S., demonstrate that extreme air pollution events (high O3 and PM2.5) are typically associated with stagnation events. Recent work showed that in a changing climate high air pollution events are likely to increase in frequency and duration. Within this work we examine meteorological and surface ozone observations from CASTNet over the U.S. and EMEP over Europe and "idealized" simulations with the GFDL AM3 chemistry-climate model, which isolate the role of climate change on air quality. Specifically, we examine an "idealized 1990s" simulation, forced with 20-year mean monthly climatologies for sea surface temperatures and sea ice from observations for 1981-2000, and an "idealized 2090s" simulation forced by the observed climatologies plus the multi-model mean changes in sea surface temperature and sea ice simulated by 19 IPCC AR-4 models under the A1B scenario for 2081-2100. With innovative statistical tools (empirical orthogonal functions (EOFs) and statistics of extremes (EVT)), we analyze the frequency distribution of past, present and future extreme air pollution events over the Eastern United States and Europe. The upper tail of observed values at individual stations (e.g., within the CASTNet), i.e., the extremes (maximum daily 8-hour average (MDA8) O3>60ppb) are poorly described by a Gaussian distribution. However, further analysis showed that applying Peak-Over-Threshold-models, better capture the extremes and allows us to estimate return levels of pollution events above certain threshold values of interest. We next apply EOF analysis to identify regions that vary coherently within the ground-based monitoring networks. Over the United States, the first EOF obtained from the model in both the 1990s and 2090s idealized simulations identifies the

  1. Air quality effects of alternative fuels. Final report

    SciTech Connect

    Guthrie, P.; Ligocki, M.; Looker, R.; Cohen, J.

    1997-11-01

    To support the Alternative Fuels Utilization Program, a comparison of potential air quality effects of alternative transportation fuels is being performed. This report presents the results of Phase 1 of this program, focusing on reformulated gasoline (RFG), methanol blended with 15 percent gasoline (M85), and compressed natural gas (CNG). The fuels are compared in terms of effects on simulated future concentrations of ozone and mobile source air toxics in a photochemical grid model. The fuel comparisons were carried out for the future year 2020 and assumed complete replacement of gasoline in the projected light-duty gasoline fleet by each of the candidate fuels. The model simulations were carried out for the areas surrounding Los Angeles and Baltimore/DC, and other (non-mobile) sources of atmospheric emissions were projected according to published estimates of economic and population growth, and planned emission control measures specific to each modeling domain. The future-year results are compared to a future-year run with all gasoline vehicle emissions removed. The results of the comparison indicate that the use of M85 is likely to produce similar ozone and air toxics levels as those projected from the use of RFG. Substitution of CNG is projected to produce significantly lower levels of ozone and the mobile source air toxics than those projected for RFG or M85. The relative benefits of CNG substitution are consistent in both modeling domains. The projection methodologies used for the comparison are subject to a large uncertainty, and modeled concentration distributions depend on meteorological conditions. The quantitative comparison of fuel effects is thus likely to be sensitive to alternative assumptions. The consistency of the results for two very different modeling domains, using very different base assumptions, lends credibility to the qualitative differentiation among these fuels. 32 refs., 42 figs., 47 tabs.

  2. Impacts of Global Climate Variations and Changes on U.S. Air Quality

    NASA Astrophysics Data System (ADS)

    Liang, X.; Zhu, J.; Lei, H.; Wuebbles, D. J.

    2011-12-01

    This study will demonstrate how global climate variations and changes affect U.S. air quality: First, the Bermuda high plays a critical role on regional climate and air quality variations over the U.S. Observational data reveal that, in summer, a more westward extension of the high enhances the Great Plains low-level jet (LLJ) along its west flank. The enhanced transport of cleaner marine air from the Gulf of Mexico reduces ozone along the LLJ path across the Great Plains to the Midwest. In contrast, larger transport of more polluted air from the Midwest to New England and more frequent air stagnation under the control of the high over the Southeast increase ozone along most of the eastern coastal States. This Bermuda high-induced ozone oscillation between the central U.S. and eastern coastal States exhibits strong decadal variations that must be considered in the dynamic management of the U.S. air quality. Second, long-range transport of pollutants under changing climate has important consequences on U.S. air quality projections. The actual outcome, however, strongly depends on the model ability to resolve the key physical and chemical processes. Here we illustrate how an improved physical dust aerosol model (PDAM) leads to substantially different projections of future U.S. PM 2.5 concentrations from existing studies. The incorporation of PDAM remarkably improves the CAM-Chem's ability in simulating the present aerosol distribution. Without PDAM, CAM-Chem projects that future PM2.5 will decrease over most of the U.S. due to emissions reduction for both A1B and A1FI scenarios; the changes are essentially the same between the two scenarios, with largest decreases of 8-15 μg m-3 over the Midwest-Northeast. This is similar to the general conclusion in the published literature. On the other hand, with PDAM, the A1B result remains almost the same, but the A1FI outcome shows large increases of 3-15 μg m-3 over the central U.S. In the southern part, these increases

  3. Mathematical Modeling of Radiocesium Migration and Air Dose Rate Changes in Eastern Fukushima Prefecture

    NASA Astrophysics Data System (ADS)

    Kitamura, A.; Sakuma, K.; Kurikami, H.; Malins, A.; Okumura, M.; Itakura, M.; Yamada, S.; Machida, M.

    2015-12-01

    Radioactive cesium that was deposited over Fukushima Prefecture after the accident at the Fukushima Daiichi nuclear power plant station is one of the major concerns regarding health physics today. Its migration is primarily by soil erosion and sediment transport within surface water during times of heavy rainfall and flooding. In order to predict the future distribution of radioactive cesium and resulting air dose rate at any location in Fukushima, we have integrated a number of mathematical models covering different time and spatial scales. In this presentation we report our overall scheme of prediction starting from sediment and radioactive cesium movement and resulting long term air dose rate changes. Specifically, we present simulation results of sediment movement and radioactive cesium migration using semi-empirical and physics based watershed models, and that of sediment and radioactive cesium behavior in a dam reservoir using one and two dimensional river simulation models. The model's results are compared with ongoing field monitoring.

  4. Macrolichens as biomonitors of air-quality change in western Pennsylvania

    SciTech Connect

    McClenahen, J.R.; Davis, D.D.; Hutnik, R.J.

    2007-07-01

    Species richness of corticolous macrolichens was monitored at one- or two-year intervals on a total of 63 plots from 1997-2003 in a region of west-central Pennsylvania that included four coal-fired power generating stations and an industrial city. Lichen richness significantly increased from an average of 5.7 species/plot in 1997 to 9.3 species/plot in 2003. A linear mean rate of gain in species on regional monitoring plots was 0.56 species/yr. Plots along a major ridge top had a slower but significant gain in richness, and a localized area flanked by the city and two generating stations exhibited less lichen recolonization. Our results confirm the value of macrolichens as indicators of air quality and the importance of examining temporal as well as spatial changes in lichen richness to ascertain air-quality status.

  5. Can air temperature be used to project influences of climate change on stream temperature?

    USGS Publications Warehouse

    Arismendi, Ivan; Safeeq, Mohammad; Dunham, Jason B.; Johnson, Sherri L.

    2014-01-01

    Worldwide, lack of data on stream temperature has motivated the use of regression-based statistical models to predict stream temperatures based on more widely available data on air temperatures. Such models have been widely applied to project responses of stream temperatures under climate change, but the performance of these models has not been fully evaluated. To address this knowledge gap, we examined the performance of two widely used linear and nonlinear regression models that predict stream temperatures based on air temperatures. We evaluated model performance and temporal stability of model parameters in a suite of regulated and unregulated streams with 11–44 years of stream temperature data. Although such models may have validity when predicting stream temperatures within the span of time that corresponds to the data used to develop them, model predictions did not transfer well to other time periods. Validation of model predictions of most recent stream temperatures, based on air temperature–stream temperature relationships from previous time periods often showed poor performance when compared with observed stream temperatures. Overall, model predictions were less robust in regulated streams and they frequently failed in detecting the coldest and warmest temperatures within all sites. In many cases, the magnitude of errors in these predictions falls within a range that equals or exceeds the magnitude of future projections of climate-related changes in stream temperatures reported for the region we studied (between 0.5 and 3.0 °C by 2080). The limited ability of regression-based statistical models to accurately project stream temperatures over time likely stems from the fact that underlying processes at play, namely the heat budgets of air and water, are distinctive in each medium and vary among localities and through time.

  6. Effects of Ambient Air Pollution Exposure on Olfaction: A Review

    PubMed Central

    Ajmani, Gaurav S.; Suh, Helen H.; Pinto, Jayant M.

    2016-01-01

    Background: Olfactory dysfunction affects millions of people worldwide. This sensory impairment is associated with neurodegenerative disease and significantly decreased quality of life. Exposure to airborne pollutants has been implicated in olfactory decline, likely due to the anatomic susceptibility of the olfactory nerve to the environment. Historically, studies have focused on occupational exposures, but more recent studies have considered effects from exposure to ambient air pollutants. Objectives: To examine all relevant human data evaluating a link between ambient pollution exposure and olfaction and to review supporting animal data in order to examine potential mechanisms for pollution-associated olfactory loss. Methods: We identified and reviewed relevant articles from 1950 to 2015 using PubMed and Web of Science and focusing on human epidemiologic and pathophysiologic studies. Animal studies were included only to support pertinent data on humans. We reviewed findings from these studies evaluating a relationship between environmental pollutant exposure and olfactory function. Results: We identified and reviewed 17 articles, with 1 additional article added from a bibliography search, for a total of 18 human studies. There is evidence in human epidemiologic and pathologic studies that increased exposure to ambient air pollutants is associated with olfactory dysfunction. However, most studies have used proxies for pollution exposure in small samples of convenience. Human pathologic studies, with supporting animal work, have also shown that air pollution can contact the olfactory epithelium, translocate to the olfactory bulb, and migrate to the olfactory cortex. Pollutants can deposit at each location, causing direct damage and disruption of tissue morphology or inducing local inflammation and cellular stress responses. Conclusions: Ambient air pollution may impact human olfactory function. Additional studies are needed to examine air pollution

  7. Effecting Change in a Resistant Organization.

    ERIC Educational Resources Information Center

    Caldwell, Patricia F.; Gould, Edward

    In an effort to overcome organizational resistance to change, Victor Valley College, in Victorville, California, has utilized a seven-part strategy to enable leaders to empower others and effect change. Step 1 requires the development of a visionary plan, so that changes have a meaningful context. Step 2 calls for an assessment of the campus…

  8. Impacts of rainfall and air temperature variations due to climate change upon hydrological characteristics: a case study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rainfall and air temperature variations resulting from climate change are important driving forces to alter hydrologic processes in watershed ecosystems. This study investigated impacts of past and potential future rainfall and air temperature variations upon water discharge, water outflow (from th...

  9. Adverse health effects of air pollutants in a nonsmoking population.

    PubMed

    Pope, C A

    1996-07-17

    Utah Valley has provided an interesting and unique opportunity to evaluate the health effects of respirable particulate air pollution (PM10). Residents of this valley are predominantly nonsmoking members of the Church of Jesus Christ of Latter-day Saints (Mormons). The area has moderately high average PM10 levels with periods of highly elevated PM10 concentrations due to local emissions being trapped in a stagnant air mass near the valley floor during low-level temperature inversion episodes. Due to a labor dispute, there was intermittent operation of the single largest pollution source, an old integrated steel mill. Levels of other common pollutants including sulfur dioxide, ozone, and acidic aerosol are relatively low. Studies specific to Utah Valley have observed that elevated PM10 concentrations are associated with: (1) decreased lung function; (2) increased incidence of respiratory symptoms; (3) increased school absenteeism; (4) increased respiratory hospital admissions; and (5) increased mortality, especially respiratory and cardiovascular mortality.

  10. Encapsulated graphene field-effect transistors for air stable operation

    SciTech Connect

    Alexandrou, Konstantinos Kymissis, Ioannis; Petrone, Nicholas; Hone, James

    2015-03-16

    In this work, we report the fabrication of encapsulated graphene field effects transistors (GFETs) with excellent air stability operation in ambient environment. Graphene's 2D nature makes its electronics properties very sensitive to the surrounding environment, and thus, non-encapsulated graphene devices show extensive vulnerability due to unintentional hole doping from the presence of water molecules and oxygen limiting their performance and use in real world applications. Encapsulating GFETs with a thin layer of parylene-C and aluminum deposited on top of the exposed graphene channel area resulted in devices with excellent electrical performance stability for an extended period of time. Moisture penetration is reduced significantly and carrier mobility degraded substantially less when compared to non-encapsulated control devices. Our CMOS compatible encapsulation method minimizes the problems of environmental doping and lifetime performance degradation, enabling the operation of air stable devices for next generation graphene-based electronics.

  11. Air pathway effects of nuclear materials production at the Hanford Site, 1983 to 1992

    SciTech Connect

    Patton, G.W.; Cooper, A.T.

    1993-10-01

    This report describes the air pathway effects of Hanford Site operations from 1983 to 1992 on the local environment by summarizing the air concentrations of selected radionuclides at both onsite and offsite locations, comparing trends in environment concentrations to changing facility emissions, and briefly describing trends in the radiological dose to the hypothetical maximally exposed member of the public. The years 1983 to 1992 represent the last Hanford Site plutonium production campaign, and this report deals mainly with the air pathway effects from the 200 Areas, in which the major contributors to radiological emissions were located. An additional purpose for report was to review the environmental data for a long period of time to provide insight not available in an annual report format. The sampling and analytical systems used by the Surface Environmental Surveillance Project (SESP) to collect air samples during the period of this report were sufficiently sensitive to observe locally elevated concentrations of selected radionuclides near onsite source of emission as well as observing elevated levels, compared to distant locations, of some radionuclides at the down wind perimeter. The US DOE Derived Concentration Guides (DCGs) for airborne radionuclides were not exceeded for any air sample collected during 1983 to 1992, with annual average concentrations of all radionuclides at the downwind perimeter being considerably below the DCG values. Air emissions at the Hanford Site during the period of this report were dominated by releases from the PUREX Plant, with {sup 85}Kr being the major release on a curie basis and {sup 129}I being the major release on a radiological dose basis. The estimated potential radiological dose from Hanford Site point source emissions to the hypothetical maximally exposed individual (MEI) ranged from 0. 02 to 0.22 mrem/yr (effective dose equivalent), which is well below the DOE radiation limit to the public of 100 mrem/yr.

  12. Mobile Air Monitoring Data Processing Strategies and Effects on Spatial Air Pollution Trends

    EPA Science Inventory

    The collection of real-time air quality measurements while in motion (i.e., mobile monitoring) is currently conducted worldwide to evaluate in situ emissions, local air quality trends, and air pollutant exposure. This measurement strategy pushes the limits of traditional data an...

  13. An overview of climate change metrics, latest developments and links with air quality (Invited)

    NASA Astrophysics Data System (ADS)

    Forster, P.

    2013-12-01

    Greenhouse gas (GHG) metrics underpin most climate policies by allowing emissions of different GHGs and other forcing agents to be expressed in a common unit. They have potentially benefited climate policy by allowing substitution among different gases ( a so called 'basket approach'). The choice of metric and especially its time horizon depend on the policy context and there is no perfect metric as no single metric can capture all the nuances of the climate and/or air quality effects policy makers maybe interested in addressing. This is especially true when considering regional effects. We will discuss case studies for aviation emissions and black carbon emissions to test specific situations where pragmatic metric choice can guide sensible policy decisions. We give several examples of clear win-win situations for both air quality and climate, where decisions would be relatively insensitive to metric choice.

  14. Colour changes of a historical Gotland sandstone caused by laser surface cleaning in ambient air and N2 flow

    NASA Astrophysics Data System (ADS)

    Jasińska, M.; Nowak, A.; Łukaszewicz, J. W.; Śliwiński, G.

    2008-07-01

    The surface discoloration due to laser cleaning was investigated for a historical Gotland sandstone. The difference in discoloration for cleaning performed in air and in the shielding environment of N2 flowing at low velocities was studied by means of colorimetry and scanning electron microscopy and energy dispersive X-ray spectroscopy techniques. For ablative removal of the natural as well as artificially applied encrustation a pulsed 1064-nm laser operated at a fluence of 0.5 J/cm2 was applied. It was observed that the natural colour variations (ΔL*=21; Δb*=23) of the stone can completely screen the laser-induced changes. Under conditions of shielding with nitrogen, darkening and yellowing slightly stronger than those occurring in the ambient air were revealed for the laser-cleaned, artificially crusted samples and the effect was independent of the gas-flow velocity. The observed difference confirmed the contribution of iron oxidation to the laser-induced yellowing and showed that the presence of oxygen in the ambient air affects favourably the cleaning by supporting removal of a variety of combustible surface remnants and crust components of organic as well as inorganic origin.

  15. Predicting effects of climate and land use change on human well-being via changes in ecosystem services

    EPA Science Inventory

    Landuse and climate change have affected biological systems in many parts of the world, and are projected to further adversely affect associated ecosystem goods and services, including provisioning of clean air, clean water, food, and biodiversity. Such adverse effects on ecosyst...

  16. Evaluation of Impacts of Landuse Changes on Air Quality in Hyderabad Metropolis Using Remote Sensing and GIS - A Case Study from Indian Sub-Continent

    NASA Astrophysics Data System (ADS)

    Vuppala, P.; S. S, A.; Mareddy, A.

    2004-12-01

    Around the world cities in developing countries are rapidly growing as more and more people become urban dwellers resulting in increased level of air pollution caused by changes in transportation, energy production and industrial activities. Air quality is an issue of critical importance in view of the accumulating evidence showing the adverse effects of pollution on human health, agricultural crops, manmade environments and ecosystems. An integrated study for identification of appropriate sites for representative evaluation of air pollution, novel means of monitoring air quality, identifying the predominant sources of pollution, effective assessment of air quality and evaluation of different management strategies essential for the development of a healthy and livable region is carried out for Hyderabad metropolis in India using Remote sensing and Geographical Information System (GIS) based assessment tools. Correlation studies between the concentration level of pollutants in urban air and urban land use are also dealt with. Municipal Corporation of Hyderabad (MCH) is divided into eleven planning zones out of which the present study area i.e. Zone I & IIA comprises of industrial, highly commercial and densely populated areas, apart from medium and sparse residential areas making it environmentally sensitive. Sampling locations were identified based on the land use/ land cover of the region and air samples were collected from areas having varying land use patterns using a high volume air sampler. The samples were then analyzed for the presence of Sulphur oxides(SO--x), Oxides of Nitrogen(NO--x), Total Suspended Particulate Matter(TSPM) and Respirable Suspended Particulate Matter(RSPM) using standard protocols and maps showing spatial distribution of SOx, NO--x, TSPM & RSPM were prepared using curve fitting technique of Arc/Info & ArcView GIS software. Air Quality Index (AQI), indicating the overall quality of air and extent of pollution is also calculated, based on

  17. Multiple Threats to Child Health from Fossil Fuel Combustion: Impacts of Air Pollution and Climate Change

    PubMed Central

    Perera, Frederica P.

    2016-01-01

    Background: Approaches to estimating and addressing the risk to children from fossil fuel combustion have been fragmented, tending to focus either on the toxic air emissions or on climate change. Yet developing children, and especially poor children, now bear a disproportionate burden of disease from both environmental pollution and climate change due to fossil fuel combustion. Objective: This commentary summarizes the robust scientific evidence regarding the multiple current and projected health impacts of fossil fuel combustion on the young to make the case for a holistic, child-centered energy and climate policy that addresses the full array of physical and psychosocial stressors resulting from fossil fuel pollution. Discussion: The data summarized here show that by sharply reducing our dependence on fossil fuels we would achieve highly significant health and economic benefits for our children and their future. These benefits would occur immediately and also play out over the life course and potentially across generations. Conclusion: Going beyond the powerful scientific and economic arguments for urgent action to reduce the burning of fossil fuels is the strong moral imperative to protect our most vulnerable populations. Citation: Perera FP. 2017. Multiple threats to child health from fossil fuel combustion: impacts of air pollution and climate change. Environ Health Perspect 125:141–148; http://dx.doi.org/10.1289/EHP299 PMID:27323709

  18. Short term effects of criteria air pollutants on daily mortality in Delhi, India

    NASA Astrophysics Data System (ADS)

    Maji, Sanjoy; Ahmed, Sirajuddin; Siddiqui, Weqar Ahmad; Ghosh, Santu

    2017-02-01

    Various epidemiological studies conducted in different parts of the world have conclusively established that the adverse health effects are associated with common urban air pollutants. Although several recent studies revealed the poor air quality status in Delhi, but limited evidence of the impact of criterion air pollutants on human health remains a big limitation for relevant policy changes. So we conducted a time series to estimate the short term effects of ambient air pollution on all-natural-cause mortality in Delhi for the period 2008 to 2010. The study examined the impact of criteria air pollutants [particulate matter less than 10 μm in diameter (PM10), sulphur di-oxide (SO2), Nitrogen di-oxide (NO2), Carbon monoxide (CO) and Ozone (O3)] on daily all-cause-mortality rate. A semi-parametric regression model was developed to estimate the short term effects of air pollutants on daily all-natural-cause-mortality adjusting nonlinear confounding of time, temperature and relative humidity. A significant association of all-natural-cause mortality in association with short-term exposure to particulate as well as the gaseous pollutants were observed. The study estimated 0.14% (95% CI 0.02%-0.26%) increase in all-cause-mortality for every 10 μg/m3 increase in PM10 concentration. Among the gaseous pollutants, NO2 has been found to show most significant positive association of 1.00% (95% CI 0.07%-1.93%) increase in all-cause-mortality with every 10 μg/m3 increase in daily NO2 concentration. The effect of O3 and CO has been observed to be significant after controlling the effects of NO2. Analysis by different age groups reveals that particulate matter has maximum effect estimate in the age group ≥65 years (RR 1.002, 95% CI 1.000 to 1.004) whereas gaseous pollutants have been found to exhibit maximum effect estimate (RR 1.016, 95% CI 1.002 to 1.030) in the age group 5-44 years. The results of the present effect estimates appeared consistent with previous findings and

  19. Air mass distribution and the heterogeneity of the climate change signal in the Hudson Bay/Foxe Basin region, Canada

    NASA Astrophysics Data System (ADS)

    Leung, Andrew; Gough, William

    2016-08-01

    The linkage between changes in air mass distribution and temperature trends from 1971 to 2010 is explored in the Hudson Bay/Foxe Basin region. Statistically significant temperature increases were found of varying spatial and temporal magnitude. Concurrent statistically significant changes in air mass frequency at the same locations were also detected, particularly in the declining frequency of dry polar (DP) air. These two sets of changes were found to be linked, and we thus conclude that the heterogeneity of the climatic warming signal in the region is at least partially the result of a fundamental shift in the concurrent air mass frequency in addition to global and regional changes in radiative forcing due to increases in long-lived greenhouse gases.

  20. EPA Provides $2.3 Million to Two Universities in Atlanta to Protect Air Quality in a Changing Climate

    EPA Pesticide Factsheets

    ATLANTA - Today, the U.S. Environmental Protection Agency (EPA) announced $8.5 million in research funding to 12 universities to protect air quality from the current and future challenges associated with the impacts of climate change.

  1. Aerosol Absorption by Black Carbon and Dust: Implications of Climate Change and Air Quality in Asia

    NASA Technical Reports Server (NTRS)

    Chin, Mian

    2010-01-01

    Atmospheric aerosol distributions from 2000 to 2007 are simulated with the global model GOCART to attribute light absorption by aerosol to its composition and sources. We show the seasonal and interannual variations of absorbing aerosols in the atmosphere over Asia, mainly black carbon and dust. and their linkage to the changes of anthropogenic and dust emissions in the region. We compare our results with observations from satellite and ground-based networks, and estimate the importance of black carbon and dust on regional climate forcing and air quality.

  2. Air quality and changes in inversion characteristics in the Western United States

    NASA Astrophysics Data System (ADS)

    Raudzens Bailey, A.; Chase, T. N.

    2009-12-01

    Though noxious emissions are the root cause of poor air quality, meteorological conditions are largely responsible for deviations in mean pollution concentrations. Temperature inversions, for example, are a common feature of high pollution episodes around the world. Characterized by an inverted lapse rate, in which temperature increases with height in the atmosphere, inversions trap pollutants in a cold pool under a warmer layer of air. The resulting atmospheric stagnation inhibits pollutants from dispersing out of the region. Climate modeling studies suggest that the meteorological conditions that favor atmospheric stagnation will increase as greenhouse gas concentrations alter global climate. To put this hypothesis to the test, we analyze upper air soundings for the period 1994-2008 from six Southwestern cities: Denver, Albuquerque, El Paso, Tucson, Flagstaff, and Salt Lake City. We note that while the overall strength (temperature difference) of low-level afternoon inversions increased through 2006, the frequency of inversions decreased for all six locations. We correlate these findings with the North American Regional Reanalysis, using Self-Organizing Maps to partition synoptic-scale meteorological patterns between days when inversions are present and absent. During the 15-year period of analysis, we test for significant changes in synoptic meteorology to determine whether large-scale weather patterns are responsible for the observed variations in inversion strength and frequency across the six sites.

  3. Project ATLANTA (Atlanta Land use Analysis: Temperature and Air Quality): Use of Remote Sensing and Modeling to Analyze How Urban Land Use Change Affects Meteorology and Air Quality Through Time

    NASA Technical Reports Server (NTRS)

    Quattrochi, Dale A.; Luvall, Jeffrey C.; Estes, Maurice G., Jr.

    1999-01-01

    This paper presents an overview of Project ATLANTA (ATlanta Land use ANalysis: Temperature and Air-quality) which is an investigation that seeks to observe, measure, model, and analyze how the rapid growth of the Atlanta, Georgia metropolitan area since the early 1970's has impacted the region's climate and air quality. The primary objectives for this research effort are: (1) To investigate and model the relationships between land cover change in the Atlanta metropolitan, and the development of the urban heat island phenomenon through time; (2) To investigate and model the temporal relationships between Atlanta urban growth and land cover change on air quality; and (3) To model the overall effects of urban development on surface energy budget characteristics across the Atlanta urban landscape through time. Our key goal is to derive a better scientific understanding of how land cover changes associated with urbanization in the Atlanta area, principally in transforming forest lands to urban land covers through time, has, and will, effect local and regional climate, surface energy flux, and air quality characteristics. Allied with this goal is the prospect that the results from this research can be applied by urban planners, environmental managers and other decision-makers, for determining how urbanization has impacted the climate and overall environment of the Atlanta area. Multiscaled remote sensing data, particularly high resolution thermal infrared data, are integral to this study for the analysis of thermal energy fluxes across the Atlanta urban landscape.

  4. The Dynamic Characteristic and Hysteresis Effect of an Air Spring

    NASA Astrophysics Data System (ADS)

    Löcken, F.; Welsch, M.

    2015-02-01

    In many applications of vibration technology, especially in chassis, air springs present a common alternative to steel spring concepts. A design-independent and therefore universal approach is presented to describe the dynamic characteristic of such springs. Differential and constitutive equations based on energy balances of the enclosed volume and the mountings are given to describe the nonlinear and dynamic characteristics. Therefore all parameters can be estimated directly from physical and geometrical properties, without parameter fitting. The numerically solved equations fit very well to measurements of a passenger car air spring. In a second step a simplification of this model leads to a pure mechanical equation. While in principle the same parameters are used, just an empirical correction of the effective heat transfer coefficient is needed to handle some simplification on this topic. Finally, a linearization of this equation leads to an analogous mechanical model that can be assembled from two common spring- and one dashpot elements in a specific arrangement. This transfer into "mechanical language" enables a system description with a simple force-displacement law and a consideration of the nonobvious hysteresis and stiffness increase of an air spring from a mechanical point of view.

  5. Joint Effects of Ambient Air Pollutants on Pediatric Asthma Emergency Department Visits in Atlanta, 1998–2004

    EPA Science Inventory

    Background: Because ambient air pollution exposure occurs in the form of mixtures, consideration of joint effects of multiple pollutants may advance our understanding of air pollution health effects. Methods: We assessed the joint effect of selected ambient air pollutant com...

  6. Assessment of health effects in epidemiologic studies of air pollution.

    PubMed Central

    Samet, J M; Speizer, F E

    1993-01-01

    As we increasingly recognize the complexity of the pollutants in indoor and outdoor microenvironments, a broad array of inhaled mixtures has assumed scientific, public health, and regulatory importance. Few adverse effects of environmental pollutants are specific, that is, uniquely associated with a single agent; the adverse effects that might be considered in an investigation of the consequences of exposure to an inhaled complex mixture are generally nonspecific. In the context of this paper, we will refer to binary mixtures as complex, though we realize that a more precise definition of complexity would restrict the term to mixtures of three or more constituents. Their causes potentially include not only pollutant exposures through the medium of inhaled air but other environmental agents, such as infectious organisms and radiation, and inherent characteristics of the exposed persons, such as atopy. We review the outcome measures that have been used in epidemiologic studies of the health effects of single pollutants and complex mixtures. Some of these outcome measures have been carefully standardized, whereas others need similar standardization and modification to improve sensitivity and specificity for investigating the health effects of air pollution. PMID:8206024

  7. Effects of air pollution on children’s pulmonary health

    NASA Astrophysics Data System (ADS)

    Tabaku, Afrim; Bejtja, Gazmend; Bala, Silvana; Toci, Ervin; Resuli, Jerina

    2011-12-01

    IntroductionMany reports regarding the effects of air pollution on children's respiratory health have appeared in the scientific literature. Some investigators found increases in persistent cough and phlegm, bronchitis, and early respiratory infections in communities with poor air quality. The purpose of this survey was to compare the pulmonary function of children living in urban area of Tirana city with children living in suburban area of the city. Material and methodsThis survey is carried out during 2004-2005 period on 238 children living in urban area and in 72 children living in suburban area, measuring dynamic pulmonary function. A questionnaire was used to collect data on sex, current respiratory symptoms, allergy diagnosed by the physician, parent education and smoking habit of parents, presence of animals, synthetic carpets and moulds in their houses. The selection of schools, and children included in this survey was done by randomized method. Also, we have measured and classic air pollutants. ResultsComparing the results of values of pulmonary function of two groups of children, we have shown that differences were significant ( p 0.001), whereas comparing symptoms were for cough ( p 0.011) and for phlegm ( p 0.032). The level of particulate matter (PM10) and total suspended matter (TSP) were over the recommended limit values, whereas the levels of other pollutants have resulted within recommended levels of World Health Organization (WHO) ConclusionsThe results of this survey suggest that air pollution is associated with respiratory health of children causing a slight decrease in values of pulmonary function in children of urban area compared with those of suburban area.

  8. Impact of aerosol direct effect on East Asian air quality during the EAST-AIRE campaign

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Allen, Dale J.; Pickering, Kenneth E.; Li, Zhanqing; He, Hao

    2016-06-01

    WRF-Chem simulations were performed for the March 2005 East Asian Studies of Tropospheric Aerosols: an International Regional Experiment (EAST-AIRE) Intensive Observation Campaign (IOC) to investigate the direct effects of aerosols on surface radiation and air quality. Domain-wide, WRF-Chem showed a decrease of 20 W/m2 in surface shortwave (SW) radiation due to the aerosol direct effect (ADE), consistent with observational studies. The ADE caused 24 h surface PM2.5 (particulate matter with diameter < 2.5 µm) concentrations to increase in eastern China (4.4%), southern China (10%), western China (2.3%), and the Sichuan Basin (9.6%), due to different aerosol compositions in these four regions. Conversely, surface 1 h maximum ozone was reduced by 2.3% domain-wide and up to 12% in eastern China because less radiation reached the surface. We also investigated the impact of reducing SO2 and black carbon (BC) emissions by 80% on aerosol amounts via two sensitivity simulations. Reducing SO2 decreased surface PM2.5 concentrations in the Sichuan Basin and southern China by 5.4% and decreased ozone by up to 6 ppbv in the Sichuan Basin and Southern China. Reducing BC emissions decreased PM2.5 by 3% in eastern China and the Sichuan Basin but increased surface ozone by up to 3.6 ppbv in eastern China and the Sichuan Basin. This study indicates that the benefits of reducing PM2.5 associated with reducing absorbing aerosols may be partially offset by increases in ozone at least for a scenario when NOx and VOC emissions are unchanged.

  9. CONCRETE BLOCKS' ADVERSE EFFECTS ON INDOOR AIR AND RECOMMENDED SOLUTIONS

    EPA Science Inventory

    Air infiltration through highly permeable concrete blocks can allow entry of various serious indoor air pollutants. An easy approach to avoiding these pollutants is to select a less–air-permeable concrete block. Tests show that air permeability of concrete blocks can vary by a fa...

  10. Effects of gamma-irradiation and air annealing on Yb-doped Y3Al5O12 single crystal.

    PubMed

    Zeng, Xionghui; Xu, Xiaodong; Wang, Xiaodan; Zhao, Zhiwei; Zhao, Guangjun; Xu, Jun

    2008-03-01

    The effects of gamma-irradiation on the air-annealed 10at.% Yb:Y(3)Al(5)O(12) (YAG) and air annealing on the gamma-irradiated 10at.% Yb:YAG have been studied by the difference absorption spectra before and after treatment. The gamma-irradiation and air annealing led to opposite changes of the absorption properties of the Yb:YAG crystal. After air annealing, the gamma-irradiation induced centers were totally removed and the concentration of Fe(3+) and Yb(3+) were lightly increased. For the first time, the gamma-irradiation induced valence changes between Yb(3+) and Yb(2+) ions in Yb:YAG crystals have been observed.

  11. Who benefits from environmental policy? An environmental justice analysis of air quality change in Britain, 2001-2011

    NASA Astrophysics Data System (ADS)

    Mitchell, Gordon; Norman, Paul; Mullin, Karen

    2015-10-01

    Air quality in Great Britain has improved in recent years, but not enough to prevent the European Commission (EC) taking legal action for non-compliance with limit values. Air quality is a national public health concern, with disease burden associated with current air quality estimated at 29 000 premature deaths per year due to fine particulates, with a further burden due to NO2. National small-area analyses showed that in 2001 poor air quality was much more prevalent in socio-economically deprived areas. We extend this social distribution of air quality analysis to consider how the distribution changed over the following decade (2001-2011), a period when significant efforts to meet EC air quality directive limits have been made, and air quality has improved. We find air quality improvement is greatest in the least deprived areas, whilst the most deprived areas bear a disproportionate and rising share of declining air quality including non-compliance with air quality standards. We discuss the implications for health inequalities, progress towards environmental justice, and compatibility of social justice and environmental sustainability objectives.

  12. Blood volume changes. [weightlessness effects

    NASA Technical Reports Server (NTRS)

    Johnson, P. C.; Driscoll, T. B.; Leblance, A. D.

    1974-01-01

    Analysis of radionuclide volume determinations made for the crewmembers of selected Gemini and Apollo missions showed that orbital spaceflight has an effect on red cell mass. Because the methods and the protocol developed for earlier flights were used for the crews of the three Skylab missions, direct comparisons are possible. After each Skylab mission, decreases were found in crewmembers' red cell masses. The mean red cell mass decrease of 11 percent or 232 milliliters was approximately equal to the 10 percent mean red cell mass decrease of the Apollo 14 to 17 crewmembers. The red cell mass drop was greatest and the postrecovery reticulocyte response least for crewmembers of the 28-day Skylab 2 mission. Analyses of data from the red cell mass determinations indicate that the red cell mass drops occurred in the first 30 days of flight and that a gradual recovery of the red cell mass deficits began approximately 60 days after launch. The beginning of red cell mass regeneration during the Skylab 4 flight may explain the higher postmission reticulocyte counts.

  13. Air pollution and associated human mortality: The role of air pollutant emissions, climate change and methane concentration increases during the industrial period

    NASA Astrophysics Data System (ADS)

    Fang, Y.; Naik, V.; Horowitz, L. W.; Mauzerall, D. L.

    2012-12-01

    Increases in surface ozone (O3) and fine particulate matter (≤ 2.5μm aerodynamic diameter, PM2.5) are associated with excess premature human mortalities. Here we estimate changes in surface O3 and PM2.5 since preindustrial (1860) times and the global present-day (2000) premature human mortalities associated with these changes. We go beyond previous work to analyze and differentiate the contribution of three factors: changes in emissions of short-lived air pollutants, climate change, and increased methane (CH4) concentrations, to air pollution levels and the associated premature mortalities. We use a coupled chemistry-climate model in conjunction with global population distributions in 2000 to estimate exposure attributable to concentration changes since 1860 from each factor. Attributable mortalities are estimated using health impact functions of long-term relative risk estimates for O3 and PM2.5 from the epidemiology literature. We find global mean surface PM2.5 and health-relevant O3 (defined as the maximum 6-month mean of 1-hour daily maximum O3 in a year) have increased by 8±0.16 μg/m3 and 30±0.16 ppbv, respectively, over this industrial period as a result of combined changes in emissions of air pollutants (EMIS), climate (CLIM) and CH4 concentrations (TCH4). EMIS, CLIM and TCH4 cause global average PM2.5 (O3) to change by +7.5±0.19 μg/m3 (+25±0.30 ppbv), +0.4±0.17 μg/m3 (+0.5±0.28 ppbv), and -0.02±0.01 μg/m3 (+4.3±0.33 ppbv), respectively. Total changes in PM2.5 are associated with 1.5 (95% confidence interval, CI, 1.0-2.5) million all-cause mortalities annually and in O3 are associated with 375 (95% CI, 129-592) thousand respiratory mortalities annually. Most air pollution mortality is driven by changes in emissions of short-lived air pollutants and their precursors (95% and 85% of mortalities from PM2.5 and O3 respectively). However, changing climate and increasing CH4 concentrations also increased premature mortality associated with air

  14. Air pollution and associated human mortality: the role of air pollutant emissions, climate change and methane concentration increases during the industrial period

    NASA Astrophysics Data System (ADS)

    Fang, Y.; Naik, V.; Horowitz, L. W.; Mauzerall, D. L.

    2012-09-01

    Increases in surface ozone (O3) and fine particulate matter (≤2.5 μm} aerodynamic diameter, PM2.5) are associated with excess premature human mortalities. Here we estimate changes in surface O3 and PM2.5 since preindustrial (1860) times and the global present-day (2000) premature human mortalities associated with these changes. We go beyond previous work to analyze and differentiate the contribution of three factors: changes in emissions of short-lived air pollutants, climate change, and increased methane (CH4) concentrations, to air pollution levels and the associated premature mortalities. We use a coupled chemistry-climate model in conjunction with global population distributions in 2000 to estimate exposure attributable to concentration changes since 1860 from each factor. Attributable mortalities are estimated using health impact functions of long-term relative risk estimates for O3 and PM2.5 from the epidemiology literature. We find global mean surface PM2.5 and health-relevant O3 (defined as the maximum 6-month mean of 1-h daily maximum O3 in a year) have increased by 8 ± 0.16 μg m-3 and 30 ± 0.16 ppbv, respectively, over this industrial period as a result of combined changes in emissions of air pollutants (EMIS), climate (CLIM) and CH4 concentrations (TCH4). EMIS, CLIM and TCH4 cause global average PM2.5(O3) to change by +7.5 ± 0.19 μg m-3 (+25 ± 0.30 ppbv), +0.4 ± 0.17 μg m-3 (+0.5 ± 0.28 ppbv), and -0.02 ± 0.01 μg m-3 (+4.3 ± 0.33 ppbv), respectively. Total changes in PM2.5 are associated with 1.5 (95% confidence interval, CI, 1.0-2.5) million all-cause mortalities annually and in O3 are associated with 375 (95% CI, 129-592) thousand respiratory mortalities annually. Most air pollution mortality is driven by changes in emissions of short-lived air pollutants and their precursors (95% and 85% of mortalities from PM2.5 and O3, respectively). However, changing climate and increasing CH4 concentrations also increased premature mortality

  15. Can changing the timing of outdoor air intake reduce indoor concentrations of traffic-related pollutants in schools?

    PubMed

    MacNeill, M; Dobbin, N; St-Jean, M; Wallace, L; Marro, L; Shin, T; You, H; Kulka, R; Allen, R W; Wheeler, A J

    2016-10-01

    Traffic emissions have been associated with a wide range of adverse health effects. Many schools are situated close to major roads, and as children spend much of their day in school, methods to reduce traffic-related air pollutant concentrations in the school environment are warranted. One promising method to reduce pollutant concentrations in schools is to alter the timing of the ventilation so that high ventilation time periods do not correspond to rush hour traffic. Health Canada, in collaboration with the Ottawa-Carleton District School Board, tested the effect of this action by collecting traffic-related air pollution data from four schools in Ottawa, Canada, during October and November 2013. A baseline and intervention period was assessed in each school. There were statistically significant (P < 0.05) reductions in concentrations of most of the pollutants measured at the two late-start (9 AM start) schools, after adjusting for outdoor concentrations and the absolute indoor-outdoor temperature difference. The intervention at the early-start (8 AM start) schools did not have significant reductions in pollutant concentrations. Based on these findings, changing the timing of the ventilation may be a cost-effective mechanism of reducing traffic-related pollutants in late-start schools located near major roads.

  16. Changes in future air quality, deposition, and aerosol-cloud interactions under future climate and emission scenarios

    NASA Astrophysics Data System (ADS)

    Glotfelty, Timothy; Zhang, Yang; Karamchandani, Prakash; Streets, David G.

    2016-08-01

    The prospect of global climate change will have wide scale impacts, such as ecological stress and human health hazards. One aspect of concern is future changes in air quality that will result from changes in both meteorological forcing and air pollutant emissions. In this study, the GU-WRF/Chem model is employed to simulate the impact of changing climate and emissions following the IPCC AR4 SRES A1B scenario. An average of 4 future years (2020, 2030, 2040, and 2050) is compared against an average of 2 current years (2001 and 2010). Under this scenario, by the Mid-21st century global air quality is projected to degrade with a global average increase of 2.5 ppb in the maximum 8-hr O3 level and of 0.3 μg m-3 in 24-hr average PM2.5. However, PM2.5 changes are more regional due to regional variations in primary aerosol emissions and emissions of gaseous precursor for secondary PM2.5. Increasing NOx emissions in this scenario combines with a wetter climate elevating levels of OH, HO2, H2O2, and the nitrate radical and increasing the atmosphere's near surface oxidation state. This differs from findings under the RCP scenarios that experience declines in OH from reduced NOx emissions, stratospheric recovery of O3, and increases in CH4 and VOCs. Increasing NOx and O3 levels enhances the nitrogen and O3 deposition, indicating potentially enhanced crop damage and ecosystem stress under this scenario. The enhanced global aerosol level results in enhancements in aerosol optical depth, cloud droplet number concentration, and cloud optical thickness. This leads to dimming at the Earth's surface with a global average reduction in shortwave radiation of 1.2 W m-2. This enhanced dimming leads to a more moderate warming trend and different trends in radiation than those found in NCAR's CCSM simulation, which does not include the advanced chemistry and aerosol treatment of GU-WRF/Chem and cannot simulate the impacts of changing climate and emissions with the same level of detailed

  17. Changes in future air quality, deposition, and aerosol-cloud interactions under future climate and emission scenarios

    SciTech Connect

    Glotfelty, Timothy; Zhang, Yang; Karamchandani, Prakash; Streets, David G.

    2016-08-01

    The prospect of global climate change will have wide scale impacts, such as ecological stress and human health hazards. One aspect of concern is future changes in air quality that will result from changes in both meteorological forcing and air pollutant emissions. In this study, the GU-WRF/Chem model is employed to simulate the impact of changing climate and emissions following the IPCC AR4 SRES A1B scenario. An average of 4 future years (2020, 2030, 2040, and 2050) is compared against an average of 2 current years (2001 and 2010). Under this scenario, by the Mid-21st century global air quality is projected to degrade with a global average increase of 2.5 ppb in the maximum 8-hr O3 level and of 0.3 mg m3 in 24-hr average PM2.5. However, PM2.5 changes are more regional due to regional variations in primary aerosol emissions and emissions of gaseous precursor for secondary PM2.5. Increasing NOx emissions in this scenario combines with a wetter climate elevating levels of OH, HO2, H2O2, and the nitrate radical and increasing the atmosphere’s near surface oxidation state. This differs from findings under the RCP scenarios that experience declines in OH from reduced NOx emissions, stratospheric recovery of O3, and increases in CH4 and VOCs. Increasing NOx and O3 levels enhances the nitrogen and O3 deposition, indicating potentially enhanced crop damage and ecosystem stress under this scenario. The enhanced global aerosol level results in enhancements in aerosol optical depth, cloud droplet number concentration, and cloud optical thickness. This leads to dimming at the Earth’s surface with a global average reduction in shortwave radiation of 1.2 W m2 . This enhanced dimming leads to a more moderate warming trend and different trends in radiation than those found in NCAR’s CCSM simulation, which does not include the advanced chemistry and aerosol

  18. Effects of air resistance on AT-cut quartz thickness-shear resonators.

    PubMed

    Chen, Yangyang; Wang, Ji; Du, Jianke; Zhang, Weiping; Yang, Jiashi

    2013-02-01

    We study theoretically the effects of air resistance on an AT-cut quartz plate thickness-shear mode resonator. Mindlin's two-dimensional equations for coupled thickness-shear and flexural motions of piezoelectric plates are employed for the crystal resonator. The equations of a Newtonian fluid and the equations of linear acoustics are used for the shear and compressive waves in the air surrounding the resonator, respectively. Solutions for free and electrically forced vibrations are obtained. The impedance of the resonator is calculated. The effects of air resistance are examined. It is found that air viscosity causes a relative frequency shift of the order of ppm. When the material quality factor of quartz Q = 10(5), the air viscosity and compressibility both have significant effects on resonator impedance. For resonators with larger aspect ratios the effects of air resistance are weaker, and the effect of air compressibility is weaker than air viscosity.

  19. Subway platform air quality: Assessing the influences of tunnel ventilation, train piston effect and station design

    NASA Astrophysics Data System (ADS)

    Moreno, T.; Pérez, N.; Reche, C.; Martins, V.; de Miguel, E.; Capdevila, M.; Centelles, S.; Minguillón, M. C.; Amato, F.; Alastuey, A.; Querol, X.; Gibbons, W.

    2014-08-01

    A high resolution air quality monitoring campaign (PM, CO2 and CO) was conducted on differently designed station platforms in the Barcelona subway system under: (a) normal forced tunnel ventilation, and (b) with daytime tunnel ventilation systems shut down. PM concentrations are highly variable (6-128 μgPM1 m-3, 16-314 μgPM3 m-3, and 33-332 μgPM10 m-3, 15-min averages) depending on ventilation conditions and station design. Narrow platforms served by single-track tunnels are heavily dependent on forced tunnel ventilation and cannot rely on the train piston effect alone to reduce platform PM concentrations. In contrast PM levels in stations with spacious double-track tunnels are not greatly affected when tunnel ventilation is switched off, offering the possibility of significant energy savings without damaging air quality. Sampling at different positions along the platform reveals considerable lateral variation, with the greatest accumulation of particulates occurring at one end of the platform. Passenger accesses can dilute PM concentrations by introducing cleaner outside air, although lateral down-platform accesses are less effective than those positioned at the train entry point. CO concentrations on the platform are very low (≤1 ppm) and probably controlled by ingress of traffic-contaminated street-level air. CO2 averages range from 371 to 569 ppm, changing during the build-up and exchange of passengers with each passing train.

  20. Evaluating the effectiveness of air quality regulations: A review of accountability studies and frameworks.

    PubMed

    Henneman, Lucas R F; Liu, Cong; Mulholland, James A; Russell, Armistead G

    2017-02-01

    Assessments of past environmental policies-termed accountability studies-contribute important information to the decision-making process used to review the efficacy of past policies, and subsequently aid in the development of effective new policies. These studies have used a variety of methods that have achieved varying levels of success at linking improvements in air quality and/or health to regulations. The Health Effects Institute defines the air pollution accountability framework as a chain of events that includes the regulation of interest, air quality, exposure/dose, and health outcomes, and suggests that accountability research should address impacts for each of these linkages. Early accountability studies investigated short-term, local regulatory actions (for example, coal use banned city-wide on a specific date or traffic pattern changes made for Olympic Games). Recent studies assessed regulations implemented over longer time and larger spatial scales. Studies on broader scales require accountability research methods that account for effects of confounding factors that increase over time and space. Improved estimates of appropriate baseline levels (sometimes termed "counterfactual"-the expected state in a scenario without an intervention) that account for confounders and uncertainties at each link in the accountability chain will help estimate causality with greater certainty. In the direct accountability framework, researchers link outcomes with regulations using statistical methods that bypass the link-by-link approach of classical accountability. Direct accountability results and methods complement the classical approach. New studies should take advantage of advanced planning for accountability studies, new data sources (such as satellite measurements), and new statistical methods. Evaluation of new methods and data sources is necessary to improve investigations of long-term regulations, and associated uncertainty should be accounted for at each link to

  1. Research on inert gas narcosis and air velocity effects on metabolic performance

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The effects of air velocity on metabolic performance are studied by using high forced airflow in a closed environment as a mechanism to control the concentration of volatile animal wastes. Air velocities between 100 and 200 ft/min are without significant effects on the metabolism of rats. At velocities of 200 ft/min and above, oxygen consumption and CO2 production as well as food consumption increase. In most instances, the changes are on the order of 5-10%. At the same time, the RQ for the animals increases slightly and generally correlates well with oxygen consumption and CO2 production. Experiments on the nature of inert gas narcosis show that halothane and methoxyflurane are rather potent inhibitors of the NADH:O2 oxidoreductase system in rats. These experiments suggest that the mechanism of inert gas narcosis is not mandatorily related to a membrane surface phenomenon.

  2. Impact of climate and land cover changes on tropospheric ozone air quality and public health in East Asia between 1980 and 2010

    NASA Astrophysics Data System (ADS)

    Fu, Y.; Tai, A. P. K.

    2015-09-01

    Understanding how historical climate and land cover changes have affected tropospheric ozone in East Asia would help constrain the large uncertainties associated with future East Asian air quality projections. We perform a series of simulations using a global chemical transport model driven by assimilated meteorological data and a suite of land cover and land use data to examine the public health effects associated with changes in climate, land cover, land use, and anthropogenic emissions between the 5-year periods 1981-1985 and 2007-2011 in East Asia. We find that between these two periods land cover change alone could lead to a decrease in summertime surface ozone by up to 4 ppbv in East Asia and ~ 2000 fewer ozone-related premature deaths per year, driven mostly by enhanced dry deposition resulting from climate- and CO2-induced increase in vegetation density, which more than offsets the effect of reduced isoprene emission arising from cropland expansion. Climate change alone could lead to an increase in summertime ozone by 2-10 ppbv in most regions of East Asia and ~ 6000 more premature deaths annually, mostly attributable to warming. The combined impacts (-2 to +12 ppbv) show that while the effect of climate change is more pronounced, land cover change could offset part of the climate effect and lead to a previously unknown public health benefit. While the changes in anthropogenic emissions remain the largest contributor to deteriorating ozone air quality in East Asia over the past 30 years, we show that climate change and land cover changes could lead to a substantial modification of ozone levels, and thus should come into consideration when formulating future air quality management strategies. We also show that the sensitivity of surface ozone to land cover change is more dependent on dry deposition than on isoprene emission in most of East Asia, leading to ozone responses that are quite distinct from that in North America, where most ozone

  3. Quantifying the effects of mixing and residual circulation on trends of stratospheric mean age of air

    NASA Astrophysics Data System (ADS)

    Ploeger, Felix; Abalos, Marta; Birner, Thomas; Konopka, Paul; Legras, Bernard; Müller, Rolf; Riese, Martin

    2015-04-01

    Trends in stratospheric mean age of air are driven both by changes in the (slow, large scale) residual mean mass circulation and by changes in (fast, locally acting) eddy mixing. However, to what degree both effects affect mean age trends is an open question. Here, we present a method that allows the effects of mixing and residual circulation on trends of mean age of air to be quantified. This method is based on mean age simulations with the Lagrangian chemistry transport model CLaMS driven by ERA-Interim reanalysis, and on the mean age tracer continuity equation integrated along the residual circulation. CLaMS simulated climatological mean age in the lower stratosphere shows reliable agreement with balloon borne in-situ obsevations and with satellite observations by MIPAS (Michelson Interferometer for Passive Atmospheric Sounding). During 1990--2013, CLaMS simulated mean age decreases throughout most of the stratosphere, qualitatively consistent with results based on climate model simulations (e.g., Butchart et al., 2010). Remarkably, in the Northern hemisphere subtropics and mid-latitudes above about 24km CLaMS mean age trends are insignificant, consistent with published mean age trends from in-situ observations (Engel et al., 2009). Furthermore, during 2002--2012 CLaMS mean age changes show a clear hemispheric asymmetry in agreement with MIPAS satellite observations (Stiller et al., 2012; Ploeger et al., 2014) and HCl decadal changes (Mahieu et al., 2014). We find that changes in the transit time along the residual circulation alone cannot explain the mean age trends, and including the effect of mixing integrated along the air parcel history is essential. Therefore, differences in mean age trends between models or between models and observations are likely related to differences in the integrated effect of mixing on mean age of air. Above about 550K, trends in the integrated mixing effect appear to be likely coupled to residual circulation changes. References

  4. Effect of climate change on watershed runoff

    USGS Publications Warehouse

    Wolock, D.M.; Ayers, M.A.; Hay, L.E.; McCabe, G.J.

    1989-01-01

    This paper examines forecasts of changes in watershed runoff in the Delaware River basin that result from a range of predicted effects of increased atmospheric carbon dioxide (CO2) on future precipitation, temperature, and stomatal resistance of plants. A deterministic hydrologic model, TOPMODEL, was driven with stochastic inputs of temperature and precipitation to derive the forecasts. Results indicate that the direction and magnitude of the changes in watershed runoff are dependent on the relative magnitudes of the induced changes in precipitation, temperature, and stomatal resistance. Natural variability in temperature and precipitation obscured the changes in watershed runoff even when the simulated changes in precipitation, temperature, and stomatal resistance were substantial.

  5. Air pollution and associated human mortality: the role of air pollutant emissions, climate change and methane concentration increases from the preindustrial period to present

    NASA Astrophysics Data System (ADS)

    Fang, Y.; Naik, V.; Horowitz, L. W.; Mauzerall, D. L.

    2013-02-01

    Increases in surface ozone (O3) and fine particulate matter (≤2.5 μm aerodynamic diameter, PM2.5) are associated with excess premature human mortalities. We estimate changes in surface O3 and PM2.5 from pre-industrial (1860) to present (2000) and the global present-day (2000) premature human mortalities associated with these changes. We extend previous work to differentiate the contribution of changes in three factors: emissions of short-lived air pollutants, climate change, and increased methane (CH4) concentrations, to air pollution levels and associated premature mortalities. We use a coupled chemistry-climate model in conjunction with global population distributions in 2000 to estimate exposure attributable to concentration changes since 1860 from each factor. Attributable mortalities are estimated using health impact functions of long-term relative risk estimates for O3 and PM2.5 from the epidemiology literature. We find global mean surface PM2.5 and health-relevant O3 (defined as the maximum 6-month mean of 1-h daily maximum O3 in a year) have increased by 8 ± 0.16 μg m-3 and 30 ± 0.16 ppbv (results reported as annual average ±standard deviation of 10-yr model simulations), respectively, over this industrial period as a result of combined changes in emissions of air pollutants (EMIS), climate (CLIM) and CH4 concentrations (TCH4). EMIS, CLIM and TCH4 cause global population-weighted average PM2.5 (O35) to change by +7.5 ± 0.19 μg m-3 (+25 ± 0.30 ppbv), +0.4 ± 0.17 μg m-3 (+0.5 ± 0.28 ppbv), and 0.04 ± 0.24 μg m-3 (+4.3 ± 0.33 ppbv), respectively. Total global changes in PM2.5 are associated with 1.5 (95% confidence interval, CI, 1.2-1.8) million cardiopulmonary mortalities and 95 (95% CI, 44-144) thousand lung cancer mortalities annually and changes in O3 are associated with 375 (95% CI, 129-592) thousand respiratory mortalities annually. Most air pollution mortality is driven by changes in emissions of short-lived air pollutants and their

  6. Conformational changes of a calix[8]arene derivative at the air-water interface.

    PubMed

    de Miguel, Gustavo; Pedrosa, José M; Martín-Romero, María T; Muñoz, Eulogia; Richardson, Tim H; Camacho, Luis

    2005-03-10

    The particular behavior of a p-tert-butyl calix[8]arene derivative (C8A) has been studied at the air-water interface using surface pressure-area isotherms, surface potential-area isotherms, film relaxation measurements, Brewster angle microscopy (BAM), and infrared spectroscopy for Langmuir-Blodgett films. Thus, it is observed that the properties of the film, for example, isotherms, domain formation, and FTIR spectra, recorded during the first compression cycle differ appreciably from those during the second compression and following cycles. The results obtained are interpreted on the basis of the conformational changes of the C8A molecules by surface pressure, allowing us to inquire into the inter- and intramolecular interactions (hydrogen bonds) of those molecules. Thus, the compression induces changes in the kind of hydrogen bonds from intra- and intermolecular with other C8A molecules to hydrogen bonds with water molecules.

  7. The possible role of local air pollution in climate change in West Africa

    NASA Astrophysics Data System (ADS)

    Knippertz, Peter; Evans, Mat J.; Field, Paul R.; Fink, Andreas H.; Liousse, Catherine; Marsham, John H.

    2015-09-01

    The climate of West Africa is characterized by a sensitive monsoon system that is associated with marked natural precipitation variability. This region has been and is projected to be subject to substantial global and regional-scale changes including greenhouse-gas-induced warming and sea-level rise, land-use and land-cover change, and substantial biomass burning. We argue that more attention should be paid to rapidly increasing air pollution over the explosively growing cities of West Africa, as experiences from other regions suggest that this can alter regional climate through the influences of aerosols on clouds and radiation, and will also affect human health and food security. We need better observations and models to quantify the magnitude and characteristics of these impacts.

  8. Studies with the USF/NASA toxicity screening test method - Effect of air flow and effect of fabric dye

    NASA Technical Reports Server (NTRS)

    Hilado, C. J.; Lopez, M. T.

    1976-01-01

    One sample each of commercial polyurethane and polychloroprene flexible foams were evaluated using the USF/NASA toxicity screening test method. Air flow rates of 0, 0.16, 16, and 48 ml/sec were used to determine the effect of air flow on relative toxicity. Time to first sign of incapacitation and time to death were substantially reduced with both polyurethane and polychloroprene flexible foams by the introduction of 16 to 48 ml/sec air flow. The relative toxicity rankings of these materials were not altered by changes in air flow. Under these test conditions, the polyurethane foam consistently appeared more toxic than the polychloroprene foam. Samples of six different colors from the same fabric were evaluated separately, using the USF/NASA toxicity screening test method, to determine the effect of fabric dye, if any. The material was an upholstery fabric, consisting of 46 percent cotton, 33 percent wool, and 21 percent nylon. There appeared to be no significant effect of fabric dye on relative toxicity, for this material under these test conditions.

  9. Effects of filter housing and ductwork configuration on air flow uniformity inside air cleaning filter housings

    SciTech Connect

    Paul, J.D.

    1992-12-31

    Each new HEPA filter installation presents a different physical configuration based on the system requirements the available space and designer preference. Each different configuration can result in variations of air flow uniformity inside the filter housing across the filter banks. This paper will present the results of air flow uniformity testing for six different filter housing/ductwork configurations and discuss if any of the variations in air flow uniformity is attributable to the difference in the physical arrangements for the six cases.

  10. Effects of filter housing and ductwork configuration on air flow uniformity inside air cleaning filter housings

    SciTech Connect

    Paul, J.D.

    1992-01-01

    Each new HEPA filter installation presents a different physical configuration based on the system requirements the available space and designer preference. Each different configuration can result in variations of air flow uniformity inside the filter housing across the filter banks. This paper will present the results of air flow uniformity testing for six different filter housing/ductwork configurations and discuss if any of the variations in air flow uniformity is attributable to the difference in the physical arrangements for the six cases.

  11. Assessment of climatic factors influence on interannual changes in the global surface air temperature

    NASA Astrophysics Data System (ADS)

    Gusakova, Maria; Karlin, Lev

    2014-05-01

    A model to assess a number of factors such as TSI, albedo, cloudiness and greenhouse gases including water vapour affecting global surface air temperature (SAT) changes has been developed. To develop the model solar energy transformation in the atmosphere and the other radiation fluxes transformation were investigated. It's a common knowledge that some part of the incoming solar energy is reflected into space by the Earth's surface, aerosol and cloud particles. A contribution of these components to changes in the reflected solar energy was assessed on the basis of developed linear parameterization. During the period of 2001 - 2010, clouds were found to be the basic contributor to the changes in reflected shortwave radiation. Some part of outgoing terrestrial radiation is retained in the atmosphere by greenhouse gases, water vapour and cloudiness. A contribution of these components to changes in the absorbed longwave radiation was assessed on the basis of developed linear parameterization. It was estimated that the contribution of water vapour was dominant during the analyzed period. The developed parameterization of global albedo made it possible to assess the contribution of TSI to global SAT changes. Making use of the parameterizations listed above the model has been improved. The model calculations showed that the our projections of global SAT to 2030 were lower than IPCC estimates.

  12. Advances of air pollution science: from forest decline to multiple-stress effects on forest ecosystem services.

    PubMed

    Paoletti, E; Schaub, M; Matyssek, R; Wieser, G; Augustaitis, A; Bastrup-Birk, A M; Bytnerowicz, A; Günthardt-Goerg, M S; Müller-Starck, G; Serengil, Y

    2010-06-01

    Over the past 20 years, the focus of forest science on air pollution has moved from forest decline to a holistic framework of forest health, and from the effects on forest production to the ecosystem services provided by forest ecosystems. Hence, future research should focus on the interacting factorial impacts and resulting antagonistic and synergistic responses of forest trees and ecosystems. The synergistic effects of air pollution and climatic changes, in particular elevated ozone, altered nitrogen, carbon and water availability, must be key issues for research. Present evidence suggests air pollution will become increasingly harmful to forests under climate change, which requires integration amongst various stressors (abiotic and biotic factors, including competition, parasites and fire), effects on forest services (production, biodiversity protection, soil protection, sustained water balance, socio-economical relevance) and assessment approaches (research, monitoring, modeling) to be fostered.

  13. Direct effects of energy-related air pollutants on plant sexual reproduction

    SciTech Connect

    Ragsdale, H.L.; Murdy, W.H.

    1987-12-08

    Our completed research program concentrated on the direct in vivo effects of energy-related air pollutants on plant sexual reproduction. Direct air pollution effects on plant sexual reproduction have been studied for SO{sub 2} and NO{sub 2}, two of the three major air pollutants.

  14. The Effect of Ambient Air Pollution on Sperm Quality

    PubMed Central

    Hansen, Craig; Luben, Thomas J.; Sacks, Jason D.; Olshan, Andrew; Jeffay, Susan; Strader, Lillian; Perreault, Sally D.

    2010-01-01

    Background Research has suggested an association with ambient air pollution and sperm quality. Objectives We investigated the effect of exposure to ozone (O3) and particulate matter < 2.5 μm in aerodynamic diameter (PM2.5) on sperm quality. Methods We reexamined a previous cohort study of water disinfection by-products to evaluate sperm quality in 228 presumed fertile men with different air pollution profiles. Outcomes included sperm concentration, total sperm per ejaculate (count), and morphology, as well as DNA integrity and chromatin maturity. Exposures to O3 and PM2.5 were evaluated for the 90–day period before sampling. We used multivariable linear regression, which included different levels of adjustment (i.e., without and with season and temperature) to assess the relationship between exposure to air pollutants during key periods of sperm development and adverse sperm outcomes. Results Sperm concentration and count were not associated with exposure to PM2.5, but there was evidence of an association (but not statistically significant) with O3 concentration and decreased sperm concentration and count. Additionally, a significant increase in the percentage of sperm cells with cytoplasmic drop [β = 2.64; 95% confidence interval (CI), 0.21–5.06] and abnormal head (β = 0.47; 95% CI, 0.03–0.92) was associated with PM2.5 concentration in the base model. However, these associations, along with all other sperm outcomes, were not significantly associated with either pollutant after controlling for season and temperature. Overall, although we found both protective and adverse effects, there was generally no consistent pattern of increased abnormal sperm quality with elevated exposure to O3 or PM2.5. Conclusions Exposures to O3 or PM2.5 at levels below the current National Ambient Air Quality Standards were not associated with statistically significant decrements in sperm outcomes in this cohort of fertile men. However, some results suggested effects on sperm

  15. Acute Effects of Fine Particulate Air Pollution on ST Segment Height: A Longitudinal Study

    EPA Science Inventory

    Background: The mechanisms for the relationship between particulate air pollution and cardiac disease are not fully understood. Air pollution-induced myocardial ischemia is one of the potentially important mechanisms. Methods: We investigate the acute effects and the time cours...

  16. Changes in air quality and tropospheric composition due to depletion of stratospheric ozone and interactions with climate.

    PubMed

    Tang, X; Wilson, S R; Solomon, K R; Shao, M; Madronich, S

    2011-02-01

    Air pollution will be directly influenced by future changes in emissions of pollutants, climate, and stratospheric ozone, and will have significant consequences for human health and the environment. UV radiation is one of the controlling factors for the formation of photochemical smog, which includes tropospheric ozone (O(3)) and aerosols; it also initiates the production of hydroxyl radicals (˙OH), which control the amount of many climate- and ozone-relevant gases (e.g., methane and HCFCs) in the atmosphere. Numerical models predict that future changes in UV radiation and climate will modify the trends and geographic distribution of ˙OH, thus affecting the formation of photochemical smog in many urban and regional areas. Concentrations of ˙OH are predicted to decrease globally by an average of 20% by 2100, with local concentrations varying by as much as a factor of two above and below current values. However, significant differences between modelled and measured values in a limited number of case studies show that chemistry of hydroxyl radicals in the atmosphere is not fully understood. Photochemically produced tropospheric ozone is projected to increase. If emissions of anthropogenic air pollutants from combustion of fossil fuels, burning of biomass, and agricultural activities continue to increase, concentrations of tropospheric O(3) will tend to increase over the next 20-40 years in certain regions of low and middle latitudes because of interactions of emissions, chemical processes, and climate change. Climate-driven increases in temperature and humidity will also increase production of tropospheric O(3) in polluted regions, but reduce it in more pristine regions. Higher temperatures tend to increase emissions of nitrogen oxides (NO(x)) from some soils and release of biogenic volatile organic compounds (VOCs) from vegetation, leading to greater background concentrations of ozone in the troposphere. The net effects of future changes in UV radiation

  17. The Effect of the Saharan Air Layer on the Formation of Hurricane Isabel (2003) Simulated with AIRS Data

    NASA Technical Reports Server (NTRS)

    Wu, iguang; Braun, Scott A.; Qu, John J.

    2006-01-01

    The crucial physics of how the atmosphere really accomplishes the tropical cyclogenesis process is still poorly understood. The presence of the Saharan Air Layer (SAL), an elevated mixed layer of warm and dry air that extends from Africa to the tropical Atlantic and contains a substantial amount of mineral dust, adds more complexity to the tropical cyclogenesis process in the Atlantic basin. The impact of the SAL on tropical cyclogenesis is still uncertain. Karyampudi and Carlson (1988) conclude that a strong SAL can potentially aid tropical cyclone development while Dunion and Velden (2004) argue that the SAL generally inhibits tropical cyclogenesis and intensification. Advancing our understanding of the physical mechanisms of tropical cyclogenesis and the associated roles of the SAL strongly depends on the improvement in the observations over the data-sparse ocean areas. After the Atmospheric Infrared Sounder (AIRS), the Advanced Microwave Sounding Unit (AMSU), and the microwave Humidity Sounder of Brazil (HSB) were launched with the NASA Aqua satellite in 2002, new data products retrieved from the AIRS suite became available for studying the effect of the warm, dry air mass associated with the SAL (referred to as the thermodynamic effect). The vertical profiles of the AIRS retrieved temperature and humidity provide an unprecedented opportunity to examine the thermodynamic effect of the SAL. The observational data can be analyzed and assimilated into numerical models, in which the model thermodynamic state is allowed to relax to the observed state from AIRS data. The objective of this study is to numerically demonstrate that the thermodynamic effect of the SAL on the formation of Hurricane Isabel (2003) can be largely simulated through nudging of the AIRS data.

  18. Global gene expression changes in human embryonic lung fibroblasts induced by organic extracts from respirable air particles

    PubMed Central

    2012-01-01

    Background Recently, we used cell-free assays to demonstrate the toxic effects of complex mixtures of organic extracts from urban air particles (PM2.5) collected in four localities of the Czech Republic (Ostrava-Bartovice, Ostrava-Poruba, Karvina and Trebon) which differed in the extent and sources of air pollution. To obtain further insight into the biological mechanisms of action of the extractable organic matter (EOM) from ambient air particles, human embryonic lung fibroblasts (HEL12469) were treated with the same four EOMs to assess changes in the genome-wide expression profiles compared to DMSO treated controls. Method For this purpose, HEL cells were incubated with subtoxic EOM concentrations of 10, 30, and 60 μg EOM/ml for 24 hours and global gene expression changes were analyzed using human whole genome microarrays (Illumina). The expression of selected genes was verified by quantitative real-time PCR. Results Dose-dependent increases in the number of significantly deregulated transcripts as well as dose-response relationships in the levels of individual transcripts were observed. The transcriptomic data did not differ substantially between the localities, suggesting that the air pollution originating mainly from various sources may have similar biological effects. This was further confirmed by the analysis of deregulated pathways and by identification of the most contributing gene modulations. The number of significantly deregulated KEGG pathways, as identified by Goeman's global test, varied, depending on the locality, between 12 to 29. The Metabolism of xenobiotics by cytochrome P450 exhibited the strongest upregulation in all 4 localities and CYP1B1 had a major contribution to the upregulation of this pathway. Other important deregulated pathways in all 4 localities were ABC transporters (involved in the translocation of exogenous and endogenous metabolites across membranes and DNA repair), the Wnt and TGF-β signaling pathways (associated

  19. Collaborative Leadership for Promoting Effective School Change.

    ERIC Educational Resources Information Center

    Mullen, Bennat; And Others

    1994-01-01

    When initiating major structural change in schools, collaboration among educators, community members, and business persons is vital. This publication describes the efforts of the Ysleta (Texas) Independent School District, which successfully used collaboration to promote effective school change. Within the district, the Del Valle High School has…

  20. Effects of climate change on croplands

    EPA Science Inventory

    This talk will describe likely changes in temperature and precipitation expected in the northwestern US with global climate change, and their potential impacts on Oregon croplands. The focus will be on the effects of temperature and carbon dioxide on crop productivity, weed cont...

  1. Air pollution and its influence on vegetation: Causes - Effects - Prophylaxis and therapy

    SciTech Connect

    Dassler, H.G.; Bortitz, S.

    1988-01-01

    This book presents a survey about air pollution from power stations, industry, traffic and other anthroponegic sources together with its effects on vegetation. It provides information on chronic and acute effects of air pollution in agriculture, horticulture, and forestry (including soil and animals), on symptoms of damage, immission tolerance, bioindication, methods of air and plant analysis and especially on prophylaxis and therapy in air polluted areas and on landscape planning.

  2. ASSESSING HIPPOCAMPAL CHANGES INDICATIVE OF NEUROTOXIC EFFECTS.

    EPA Science Inventory

    Subtle changes in cognitive function are often the earliest indication of neurotoxic effects in humans. The hippocampus is a large forebrain structure subserving specific kinds of information encoding and consolidation in humans and other animals. Because of it laminar structur...

  3. Stratospheric ozone changes under solar geoengineering: implications for UV exposure and air quality

    NASA Astrophysics Data System (ADS)

    Nowack, Peer Johannes; Abraham, Nathan Luke; Braesicke, Peter; Pyle, John Adrian

    2016-03-01

    Various forms of geoengineering have been proposed to counter anthropogenic climate change. Methods which aim to modify the Earth's energy balance by reducing insolation are often subsumed under the term solar radiation management (SRM). Here, we present results of a standard SRM modelling experiment in which the incoming solar irradiance is reduced to offset the global mean warming induced by a quadrupling of atmospheric carbon dioxide. For the first time in an atmosphere-ocean coupled climate model, we include atmospheric composition feedbacks for this experiment. While the SRM scheme considered here could offset greenhouse gas induced global mean surface warming, it leads to important changes in atmospheric composition. We find large stratospheric ozone increases that induce significant reductions in surface UV-B irradiance, which would have implications for vitamin D production. In addition, the higher stratospheric ozone levels lead to decreased ozone photolysis in the troposphere. In combination with lower atmospheric specific humidity under SRM, this results in overall surface ozone concentration increases in the idealized G1 experiment. Both UV-B and surface ozone changes are important for human health. We therefore highlight that both stratospheric and tropospheric ozone changes must be considered in the assessment of any SRM scheme, due to their important roles in regulating UV exposure and air quality.

  4. Development of North American emission inventories for air quality modeling under climate change.

    PubMed

    Woo, Jung-Hun; He, Shan; Tagaris, Efthimios; Liao, Kuo-Jen; Manomaiphiboon, Kasemsan; Amar, Praveen; Russell, Armistead G

    2008-11-01

    An assessment of how future climate change will impact regional air quality requires projecting emissions many decades into the future in a consistent manner. An approach that integrates the impact of both the current regulations and the longer-term national and global trends is developed to construct an emissions inventory (EI) for North America for the mid-century in support of a regional modeling study of ozone and particulate matter (PM) less than or equal to 2.5 microm (PM2.5). Because the time horizon of such a distant projection is beyond that of EIs used in typical modeling studies, it is necessary to identify a practical approach that allows the emission projections to account for emission controls and climatic and energy-use changes. However, a technical challenge arises because this requires integration of various different types of information with which emissions from human activities are associated. Often, emission information in global models has less detail and uses coarser spatiotemporal resolution. The method developed here is based on data availability, spatiotemporal coverage and resolution, and future-scenario consistency (i.e., Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios [IPCC SRES] A1B), and consists of two major steps: (1) near-future EI projection (to the year 2020), and (2) longer-term EI projection (to mid-century). The first step is based closely on the U.S. Environmental Protection Agency Clean Air Interstate Rule EI, the Environment Canada EI, as well estimates of Mexico's EI; whereas the second step follows approaches proposed by the EI from the Integrated Model to Assess the Global Environment (IMAGE), developed by Netherlands's National Institute for Public Health and the Environment (RIVM). For the United States, the year-2050 emissions for nitrogen oxides (NOx), sulfur dioxide (SO2), PM2.5, anthropogenic volatile organic compounds (VOCs), and ammonia are projected to change by -55, -55, -30, -40

  5. Effect of green roofs on air temperature; measurement study of well-watered and dry conditions

    NASA Astrophysics Data System (ADS)

    Solcerova, Anna; van de Ven, Frans; Wang, Mengyu; van de Giesen, Nick

    2016-04-01

    Rapid urbanization and increasing number and duration of heat waves poses a need for understanding urban climate and ways to mitigate extremely high temperatures. One of repeatedly suggested and often investigated methods to moderate the so called urban heat island are green roofs. This study investigates several extensive green roofs in Utrecht (NL) and their effect on air temperature right above the roof surface. Air temperature was measured 15 and 30 cm above the roof surface and also in the substrate. We show that under normal condition is air above green roof, compared to white gravel roof, colder at night and warmer during day. This suggest that green roofs might help decrease air temperatures at night, when the urban heat island is strongest, but possibly contribute to high temperatures during daytime. We also measured situation when the green roofs wilted and dried out. Under such conditions green roof exhibits more similar behavior to conventional white gravel roof. Interestingly, pattern of soil temperature remains almost the same for both dry and well-prospering green roof, colder during day and warmer at night. As such, green roof works as a buffer of diurnal temperature changes.

  6. Air Distribution Effectiveness for Residential Mechanical Ventilation: Simulation and Comparison of Normalized Exposures

    SciTech Connect

    Petithuguenin, T.D.P.; Sherman, M.H.

    2009-05-01

    The purpose of ventilation is to dilute indoor contaminants that an occupant is exposed to. Even when providing the same nominal rate of outdoor air, different ventilation systems may distribute air in different ways, affecting occupants' exposure to household contaminants. Exposure ultimately depends on the home being considered, on source disposition and strength, on occupants' behavior, on the ventilation strategy, and on operation of forced air heating and cooling systems. In any multi-zone environment dilution rates and source strengths may be different in every zone and change in time, resulting in exposure being tied to occupancy patterns.This paper will report on simulations that compare ventilation systems by assessing their impact on exposure by examining common house geometries, contaminant generation profiles, and occupancy scenarios. These simulations take into account the unsteady, occupancy-tied aspect of ventilation such as bathroom and kitchen exhaust fans. As most US homes have central HVAC systems, the simulation results will be used to make appropriate recommendations and adjustments for distribution and mixing to residential ventilation standards such as ASHRAE Standard 62.2.This paper will report on work being done to model multizone airflow systems that are unsteady and elaborate the concept of distribution matrix. It will examine several metrics for evaluating the effect of air distribution on exposure to pollutants, based on previous work by Sherman et al. (2006).

  7. The impact of past and future climate change on global human mortality due to ozone and PM2.5 outdoor air pollution

    NASA Astrophysics Data System (ADS)

    Silva, R.; West, J.; Anenberg, S.; Lamarque, J.; Shindell, D. T.; Bergmann, D. J.; Berntsen, T.; Cameron-Smith, P. J.; Collins, B.; Ghan, S. J.; Josse, B.; Nagashima, T.; Naik, V.; Plummer, D.; Rodriguez, J. M.; Szopa, S.; Zeng, G.

    2012-12-01

    Climate change can adversely affect air quality, through changes in meteorology, atmospheric chemistry, and emissions. Future changes in air pollutant emissions will also profoundly influence air quality. These changes in air quality can affect human health, as exposure to ground-level ozone and fine particulate matter (PM2.5) has been associated with premature human mortality. Here we will quantify the global mortality impacts of past and future climate change, considering the effects of climate change on air quality isolated from emission changes. The Atmospheric Chemistry and Climate Model Intercomparison Project (ACCMIP) has simulated the past and future surface concentrations of ozone and PM2.5 from each of several GCMs, for emissions from 1850 ("preindustrial") to 2000 ("present-day"), and for the IPCC AR5 Representative Concentration Pathways (RCPs) scenarios to 2100. We will use ozone and PM2.5 concentrations from simulations from five or more global models of atmospheric dynamics and chemistry, for a base year (present-day), pre-industrial conditions, and future scenarios, considering changes in climate and emissions. We will assess the mortality impacts of past climate change by using one simulation ensemble with present emissions and climate and one with present emissions but 1850 climate. We will similarly quantify the potential impacts of future climate change under the four RCP scenarios in 2030, 2050 and 2100. All model outputs will be regridded to the same resolution to estimate multi-model medians and range in each grid cell. Resulting premature deaths will be calculated using these medians along with epidemiologically-derived concentration-response functions, and present-day or future projections of population and baseline mortality rates, considering aging and transitioning disease rates over time. The spatial distributions of current and future global premature mortalities due to ozone and PM2.5 outdoor air pollution will be presented separately

  8. Ancillary human health benefits of improved air quality resulting from climate change mitigation

    PubMed Central

    Bell, Michelle L; Davis, Devra L; Cifuentes, Luis A; Krupnick, Alan J; Morgenstern, Richard D; Thurston, George D

    2008-01-01

    Background Greenhouse gas (GHG) mitigation policies can provide ancillary benefits in terms of short-term improvements in air quality and associated health benefits. Several studies have analyzed the ancillary impacts of GHG policies for a variety of locations, pollutants, and policies. In this paper we review the existing evidence on ancillary health benefits relating to air pollution from various GHG strategies and provide a framework for such analysis. Methods We evaluate techniques used in different stages of such research for estimation of: (1) changes in air pollutant concentrations; (2) avoided adverse health endpoints; and (3) economic valuation of health consequences. The limitations and merits of various methods are examined. Finally, we conclude with recommendations for ancillary benefits analysis and related research gaps in the relevant disciplines. Results We found that to date most assessments have focused their analysis more heavily on one aspect of the framework (e.g., economic analysis). While a wide range of methods was applied to various policies and regions, results from multiple studies provide strong evidence that the short-term public health and economic benefits of ancillary benefits related to GHG mitigation strategies are substantial. Further, results of these analyses are likely to be underestimates because there are a number of important unquantified health and economic endpoints. Conclusion Remaining challenges include integrating the understanding of the relative toxicity of particulate matter by components or sources, developing better estimates of public health and environmental impacts on selected sub-populations, and devising new methods for evaluating heretofore unquantified and non-monetized benefits. PMID:18671873

  9. Research on Health and Environmental Effects of Air Quality

    EPA Pesticide Factsheets

    Research has linked regulated air pollutants such as ozone and particulate matter, to lung, heart disease and other health problems. Further investigation is needed to understand the role poor air quality plays on health and disease

  10. Assessing recent air-sea freshwater flux changes using a surface temperature-salinity space framework

    NASA Astrophysics Data System (ADS)

    Grist, Jeremy P.; Josey, Simon A.; Zika, Jan D.; Evans, Dafydd Gwyn; Skliris, Nikolaos

    2016-12-01

    A novel assessment of recent changes in air-sea freshwater fluxes has been conducted using a surface temperature-salinity framework applied to four atmospheric reanalyses. Viewed in the T-S space of the ocean surface, the complex pattern of the longitude-latitude space mean global Precipitation minus Evaporation (PME) reduces to three distinct regions. The analysis is conducted for the period 1979-2007 for which there is most evidence for a broadening of the (atmospheric) tropical belt. All four of the reanalyses display an increase in strength of the water cycle. The range of increase is between 2% and 30% over the period analyzed, with an average of 14%. Considering the average across the reanalyses, the water cycle changes are dominated by changes in tropical as opposed to mid-high latitude precipitation. The increases in the water cycle strength, are consistent in sign, but larger than in a 1% greenhouse gas run of the HadGEM3 climate model. In the model a shift of the precipitation/evaporation cells to higher temperatures is more evident, due to the much stronger global warming signal. The observed changes in freshwater fluxes appear to be reflected in changes in the T-S distribution of the Global Ocean. Specifically, across the diverse range of atmospheric reanalyses considered here, there was an acceleration of the hydrological cycle during 1979-2007 which led to a broadening of the ocean's salinity distribution. Finally, although the reanalyses indicate that the warm temperature tropical precipitation dominated water cycle change, ocean observations suggest that ocean processes redistributed the freshening to lower ocean temperatures.

  11. Future Tree Effects on Air Quality and Human Health in the United States

    NASA Astrophysics Data System (ADS)

    Hirabayashi, S.; Nowak, D.

    2014-12-01

    Trees are critical green infrastructure for mitigating adverse effects associated with human population, land use, and climate change (e.g. urban heat island, greenhouse gasses, air pollution, and floods). i-Tree (www.itreetools.org) is a suite of software tools developed by the USDA Forest Service and The Davey Institute that allows users to assess urban forest structure and the ecosystem services provided. Using i-Tree, the annual effects of trees on air quality and human health in urban and rural areas of counties across the conterminous United States have been quantified for 2010 (Nowak et al. 2014). Here, we extended the study to incorporate future forest structure scenarios using a model that accounts for tree growth, mortality and new plantings. Computer simulations using local environmental data and the possible leaf area index (LAI) for deciduous or evergreen tree covers were performed in urban and rural areas of counties across the conterminous United States. The result is a tree effects database on air pollutant removal (CO, NO2, O3, PM10, PM2.5 and SO2), biogenic emission of volatile organic compounds (VOCs), and monetary values associated with human health quantified per unit tree cover area with deciduous or evergreen trees and LAI ranging from 0 to 18 within each modeling domain. With these data, the potential annual effects that trees have on air quality and human health under future scenarios of urban forest extent can be readily derived for anywhere in the conterminous United States. The developed database will be integrated into i-Tree's suite in 2015 to enhance its functionality in estimating tree effects under the future scenarios.

  12. Measuring the impact of energy consumption and air quality indicators on climate change: evidence from the panel of UNFCC classified countries.

    PubMed

    Ozturk, Ilhan

    2015-10-01

    This study examines the relationship between energy consumption, air pollution, and climate change in the panel of six economically diversified countries classified by the United Nations Framework Convention on Climate Change (UNFCC) as industrialized countries and economies in transition nations by using the panel econometric techniques for the period of 1990-2012. The results of pooled least square regression show that both the energy consumption and air quality indicators have a positive and significant relationship with the climate change, i.e., 1 % increase in energy consumption increases greenhouse gas emissions by 0.124 %, carbon dioxide emissions increase by 0.652 %, methane emissions increase by 0.123 %, and nitrous oxide emissions increase greenhouse gas emissions by 0.105 % age points. The results of fixed-effect regression and random-effect regression confirmed the deteriorating impact of air quality indicators on climate change; however, the results failed to show any significant association between energy consumption and climate change when absorbing country-specific shocks and time-variant shocks during the study time period.

  13. Cold air performance of a 12.766-centimeter-tip-diameter axial-flow cooled turbine. 2: Effect of air ejection on turbine performance

    NASA Technical Reports Server (NTRS)

    Haas, J. E.; Kofskey, M. G.

    1977-01-01

    An air cooled version of a single-stage, axial-flow turbine was investigated to determine aerodynamic performance with and without air ejection from the stator and rotor blades surfaces to simulate the effect of cooling air discharge. Air ejection rate was varied from 0 to 10 percent of turbine mass flow for both the stator and the rotor. A primary-to-air ejection temperature ratio of about 1 was maintained.

  14. The Effective Mass of a Ball in the Air

    ERIC Educational Resources Information Center

    Messer, J.; Pantaleone, J.

    2010-01-01

    The air surrounding a projectile affects the projectile's motion in three very different ways: the drag force, the buoyant force, and the added mass. The added mass is an increase in the projectile's inertia from the motion of the air around it. Here we experimentally measure the added mass of a spherical projectile in air. The results agree well…

  15. Some Effects of Air Flow on the Penetration and Distribution of Oil Sprays

    NASA Technical Reports Server (NTRS)

    Rothrock, A M; Beardsley, E G

    1929-01-01

    Tests were made to determine the effects of air flow on the characteristics of fuel sprays from fuel injection valves. Curves and photographs are presented showing the airflow throughout the chamber and the effects of the air flow on the fuel spray characteristics. It was found that the moving air had little effect on the spray penetration except with the 0.006 inch orifice. The moving air did, however, affect the oil particles on the outside of the spray cone. After spray cut-off, the air flow rapidly distributed the atomized fuel throughout the spray chamber.

  16. In vitro effects of pollutants from particulate and volatile fractions of air samples-day and night variability.

    PubMed

    Novák, Jiří; Giesy, John P; Klánová, Jana; Hilscherová, Klára

    2013-09-01

    Chemicals in air were characterized for potential interference with signaling of estrogen, androgen, and arylhydrocarbon (AhR) receptors, which are known to play an important role in endocrine-disruptive changes in vivo. Previously, effects of this type have been studied mainly in particulate matter in the ambient air from various localities. In this study, both volatile and particulate fractions of air from three sites in Banja Luka region (Bosnia and Herzegovina) were investigated to describe the distribution of endocrine-disrupting contaminants on a small spatial scale. Circadian variability of air pollution was investigated by collecting samples during both day and night. Air samples collected from urban localities at night were more potent in producing the AhR-mediated effects than those collected during daytime. This trend was not observed at the reference rural location. None of the samples showed significant estrogenic or androgenic activity. On the other hand, anti-androgenicity was detected in both particulate and vapor phases, while anti-estrogenicity was detected only in the particulate fraction of air from all localities. The AhR-mediated potencies of samples were associated primarily with non-persistent compounds. Based on the concentrations of 28 individual compounds, PAHs accounted for approximately 30 % of the AhR-mediated potency determined by the bioassay. The results show that there can be a significant difference between levels of bioactive compounds in air between daytime and nighttime.

  17. 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.

  18. Health effects of particulate air pollution and airborne desert dust

    NASA Astrophysics Data System (ADS)

    Lelieveld, J.; Pozzer, A.; Giannadaki, D.; Fnais, M.

    2013-12-01

    Air pollution by fine particulate matter (PM2.5) has increased strongly with industrialization and urbanization. In the past decades this increase has taken place at a particularly high pace in South and East Asia. We estimate the premature mortality and the years of human life lost (YLL) caused by anthropogenic PM2.5 and airborne desert dust (DU2.5) on regional and national scales (Giannadaki et al., 2013; Lelieveld et al., 2013). This is based on high-resolution global model calculations that resolve urban and industrial regions in relatively great detail. We apply an epidemiological health impact function and find that especially in large countries with extensive suburban and rural populations, air pollution-induced mortality rates have been underestimated given that previous studies largely focused on the urban environment. We calculate a global premature mortality by anthropogenic aerosols of 2.2 million/year (YLL ≈ 16 million/year) due to lung cancer and cardiopulmonary disease. High mortality rates by PM2.5 are found in China, India, Bangladesh, Pakistan and Indonesia. Desert dust DU2.5 aerosols add about 0.4 million/year (YLL ≈ 3.6 million/year). Particularly significant mortality rates by DU2.5 occur in Pakistan, China and India. The estimated global mean per capita mortality caused by airborne particulates is about 0.1%/year (about two thirds of that caused by tobacco smoking). We show that the highest premature mortality rates are found in the Southeast Asia and Western Pacific regions (about 25% and 46% of the global rate, respectively) where more than a dozen of the most highly polluted megacities are located. References: Giannadaki, D., A. Pozzer, and J. Lelieveld, Modeled global effects of airborne desert dust on air quality and premature mortality, Atmos. Chem. Phys. Discuss. (submitted), 2013. Lelieveld, J., C. Barlas, D. Giannadaki, and A. Pozzer, Model calculated global, regional and megacity premature mortality due to air pollution by ozone

  19. Protecting national parks from air pollution effects: Making sausage from science and policy

    USGS Publications Warehouse

    Baron, Jill; Blett, Tamara; Malm, William C.; Alexander, Ruth; Doremus, Holly

    2016-01-01

    The story of air pollution research, policy development, and management in national parks is a fascinating blend of cultural change, vision, interdisciplinary and interagency collaboration, and science-policy-management-stakeholder collaborations. Unable to ignore the loss of iconic vistas from regional haze and loss of fish from acid rain in the 1980s, the National Park Service (NPS) embraced an obligation to protect resources from threats originating outside park boundaries. Upholding the Organic Act requirement for parks to remain "unimpaired" for the enjoyment of future generations, and using the Clean Air Act statement that NPS has an “affirmative responsibility” to protect park resources, NPS has supported, and effectively used, research as a means to protect lands, waters, and vistas from a mostly unseen threat. Using visibility and atmospheric nitrogen deposition as examples, we will illustrate some success stories where NPS led the way to benefit not only parks, but the Nation.

  20. A numerical investigation of the effects of dry air aloft on deep convection

    NASA Astrophysics Data System (ADS)

    James, Richard P.

    A high-resolution numerical model was used to investigate the direct effects of dry air above cloud base in the environment of convective storms. Simulations of both quasi-linear convective systems and supercells were performed in which the relative humidity in a midlevel dry layer was varied while preserving the buoyancy profile and CAPE. The presence of dry air caused a reduction in overall storm intensity, as measured by updraft mass flux, total condensation and total rainfall; the reduction was more dramatic at lower values of CAPE. In high-CAPE line-type simulations, the downdraft mass flux and cold pool strength were enhanced at the rear of the trailing stratiform region in a drier environment. However, the downdraft and cold pool strengths were unchanged in the convective region, and were also unchanged or reduced in simulations of supercells and of line-type systems at lower CAPE. The effects of dry air aloft are interpreted in terms of the reduction in the rate of updraft entrainment when dry air is present, leading to decreased mass flux and a lower rate of condensate production. Smaller hydrometeor mixing ratios then exert a negative influence on the latent cooling rates associated with phase changes in the downdraft formation regions. This effect offsets the enhancement of rain evaporation that is expected to occur in a drier environment and thereby prevents the strengthening of downdrafts and low-level outflow. The modeling results reported here are inconsistent with the widespread notion that dry air aloft is favorable for stronger downdrafts and greater low-level outflow intensity. A review of the literature is presented in which it is shown that observational evidence does not unambiguously support the necessity of dry air aloft for strong downdrafts and outflow. The relative importance of environmental humidity, temperature and stability are examined, and it is shown that some observational studies may have overemphasized the role of environmental

  1. Cardiorespiratory Biomarker Responses in Healthy Young Adults to Drastic Air Quality Changes Surrounding the 2008 Beijing Olympics

    PubMed Central

    Zhang, Junfeng; Zhu, Tong; Kipen, Howard; Wang, Guangfa; Huang, Wei; Rich, David; Zhu, Ping; Wang, Yuedan; Lu, Shou-En; Ohman-Strickland, Pamela; Diehl, Scott; Hu, Min; Tong, Jian; Gong, Jicheng; Thomas, Duncan

    2014-01-01

    Associations between air pollution and cardiorespiratory mortality and morbidity have been well established, but data to support biologic mechanisms underlying these associations are limited. We designed this study to examine several prominently hypothesized mechanisms by assessing Beijing residents’ biologic responses, at the biomarker level, to drastic changes in air quality brought about by unprecedented air pollution control measures implemented during the 2008 Beijing Olympics. To test the hypothesis that changes in air pollution levels are associated with changes in biomarker levels reflecting inflammation, hemostasis, oxidative stress, and autonomic tone, we recruited and retained 125 nonsmoking adults (19 to 33 years old) free of cardiorespiratory and other chronic diseases. Using the combination of a quasi-experimental design and a panel-study approach, we measured biomarkers of autonomic dysfunction (heart rate [HR*] and heart rate variability [HRV]), of systemic inflammation and oxidative stress (plasma C-reactive protein [CRP], fibrinogen, blood cell counts and differentials, and urinary 8-hydroxy-2′-deoxyguanosine [8-OHdG]), of pulmonary inflammation and oxidative stress (fractional exhaled nitric oxide [FeNO], exhaled breath condensate [EBC] pH, EBC nitrate, EBC nitrite, EBC nitrite+nitrate [sum of the concentrations of nitrite and nitrate], and EBC 8-isoprostane), of hemostasis (platelet activation [plasma sCD62P and sCD40L], platelet aggregation, and von Willebrand factor [vWF]), and of blood pressure (systolic blood pressure [SBP] and diastolic blood pressure [DBP]). These biomarkers were measured on each subject twice before, twice during, and twice after the Beijing Olympics. For each subject, repeated measurements were separated by at least one week to avoid potential residual effects from a prior measurement. We measured a large suite of air pollutants (PM2.5 [particulate matter ≤ 2.5 μm in aerodynamic diameter] and constituents, sulfur

  2. Effect of dynamic diffusion of air, nitrogen, and helium gaseous media on the microhardness of ionic crystals with juvenile surfaces

    NASA Astrophysics Data System (ADS)

    Klyavin, O. V.; Fedorov, V. Yu.; Chernov, Yu. M.; Shpeizman, V. V.

    2015-09-01

    The load dependences of the microhardness of surface layers of NaCl and LiF ionic single crystals with juvenile surfaces and surfaces exposed to air for a long time measured in the air, nitrogen, and helium gaseous media have been investigated. It has been found that there is a change in the sign of the derivative of the microhardness as a function of the load for LiF crystals indented in helium and after their aging in air, as well as a weaker effect of the nitrogen and air gaseous media on the studied dependences as compared to NaCl crystals. It has also been found that, after the aging of the surface of NaCl crystals in air, there is a change in the sign of the derivative of the microhardness in the nitrogen and air gaseous media, as well as a pronounced change in the microhardness as a function of the time of aging the samples in air as compared to the weaker effect of the gaseous medium for LiF crystals. The obtained data have been analyzed in terms of the phenomenon of dislocation-dynamic diffusion of particles from the external medium into crystalline materials during their plastic deformation along the nucleating and moving dislocations. It has been shown that this phenomenon affects the microhardness through changes in the intensity of dislocation multiplication upon the formation of indentation rosettes in different gaseous media. The performed investigation of the microhardness of the juvenile surface of NaCl and LiF crystals in different gaseous media has revealed for the first time a different character of dislocation-dynamic diffusion of these media in a "pure" form.

  3. UNINTENDED BENEFITS: LEADERSHIP SKILLS AND BEHAVIORAL CHANGE AMONG GUATEMALAN FIELDWORKERS EMPLOYED IN A LONGITUDINAL HOUSEHOLD AIR POLLUTION STUDY*

    PubMed Central

    KUO, DEVINA; THOMPSON, LISA M.; LEE, AMY; ROMERO, CAROLINA; SMITH, KIRK R.

    2015-01-01

    The RESPIRE and CRECER studies measured the effects of reduced household air pollution (HAP) from wood-fired cookstoves on respiratory health in rural highland Guatemala. This article examines behavior change and leadership skill development in local community members who were hired as fieldworkers to assist with research. Fieldworkers administered household questionnaires, shared functions similar to community health workers, and bridged health resources to communities. A mixed-methods design for data collection (in-depth interviews, focus groups, impact drawings, knowledge questionnaire, and retrospective pre-test) was used. Purposive sampling included 10 fieldworkers and 13 local service providers. Fieldworkers showed an increase in knowledge, positive attitudes, and practices around HAP. They developed new technical, interpersonal, and leadership skills. Fieldworkers played a crucial role in building confianza (trust) with the community, bridging resources, and improving outside researchers’ relationships with locals. Recommendations for future researchers include inclusion of additional training courses and adoption of community participatory approaches. PMID:22192940

  4. Unintended benefits: leadership skills and behavioral change among Guatemalan fieldworkers employed in a longitudinal household air pollution study.

    PubMed

    Kuo, Devina; Thompson, Lisa M; Lee, Amy; Romero, Carolina; Smith, Kirk R

    2010-01-01

    The RESPIRE and CRECER studies measured the effects of reduced household air pollution (HAP) from wood-fired cookstoves on respiratory health in rural highland Guatemala. This article examines behavior change and leadership skill development in local community members who were hired as fieldworkers to assist with research. Fieldworkers administered household questionnaires, shared functions similar to community health workers, and bridged health resources to communities. A mixed-methods design for data collection (in-depth interviews, focus groups, impact drawings, knowledge questionnaire, and retrospective pre-test) was used. Purposive sampling included 10 fieldworkers and 13 local service providers. Fieldworkers showed an increase in knowledge, positive attitudes, and practices around HAP. They developed new technical, interpersonal, and leadership skills. Fieldworkers played a crucial role in building confianza (trust) with the community, bridging resources, and improving outside researchers' relationships with locals. Recommendations for future researchers include inclusion of additional training courses and adoption of community participatory approaches.

  5. Effects of business-as-usual anthropogenic emissions on air quality

    NASA Astrophysics Data System (ADS)

    Pozzer, A.; Zimmermann, P.; Doering, U. M.; van Aardenne, J.; Tost, H.; Dentener, F.; Janssens-Maenhout, G.; Lelieveld, J.

    2012-08-01

    The atmospheric chemistry general circulation model EMAC has been used to estimate the impact of anthropogenic emission changes on global and regional air quality in recent and future years (2005, 2010, 2025 and 2050). The emission scenario assumes that population and economic growth largely determine energy and food consumption and consequent pollution sources with the current technologies ("business as usual"). This scenario is chosen to show the effects of not implementing legislation to prevent additional climate change and growing air pollution, other than what is in place for the base year 2005, representing a pessimistic (but plausible) future. By comparing with recent observations, it is shown that the model reproduces the main features of regional air pollution distributions though with some imprecisions inherent to the coarse horizontal resolution (~100 km) and simplified bottom-up emission input. To identify possible future hot spots of poor air quality, a multi pollutant index (MPI), suited for global model output, has been applied. It appears that East and South Asia and the Middle East represent such hotspots due to very high pollutant concentrations, while a general increase of MPIs is observed in all populated regions in the Northern Hemisphere. In East Asia a range of pollutant gases and fine particulate matter (PM2.5) is projected to reach very high levels from 2005 onward, while in South Asia air pollution, including ozone, will grow rapidly towards the middle of the century. Around the Persian Gulf, where natural PM2.5 concentrations are already high (desert dust), ozone levels are expected to increase strongly. The population weighted MPI (PW-MPI), which combines demographic and pollutant concentration projections, shows that a rapidly increasing number of people worldwide will experience reduced air quality during the first half of the 21st century. Following this business as usual scenario, it is projected that air quality for the global

  6. Effects of business-as-usual anthropogenic emissions on air quality

    NASA Astrophysics Data System (ADS)

    Pozzer, A.; Zimmermann, P.; Doering, U. M.; van Aardenne, J.; Tost, H.; Dentener, F.; Janssens-Maenhout, G.; Lelieveld, J.

    2012-04-01

    The atmospheric chemistry general circulation model EMAC has been used to estimate the impact of anthropogenic emission changes on global and regional air quality in recent and future years (2005, 2010, 2025 and 2050). The emission scenario assumes that population and economic growth largely determine energy and food consumption and consequent pollution sources with the current technologies ("business as usual"). This scenario is chosen to show the effects of not implementing legislation to prevent additional climate change and growing air pollution, other than what is in place for the base year 2005, representing a pessimistic (but feasible) future. By comparing with recent observations, it is shown that the model reproduces the main features of regional air pollution distributions though with some imprecisions inherent to the coarse horizontal resolution (~100 km) and simplified bottom-up emission input. To identify possible future hot spots of poor air quality, a multi pollutant index (MPI), suited for global model output, has been applied. It appears that East and South Asia and the Middle East represent such hotspots due to very high pollutant concentrations, although a general increase of MPIs is observed in all populated regions in the Northern Hemisphere. In East Asia a range of pollutant gases and fine particulate matter (PM2.5) is projected to reach very high levels from 2005 onward, while in South Asia air pollution, including ozone, will grow rapidly towards the middle of the century. Around the Arabian Gulf, where natural PM2.5 concentrations are already high (desert dust), ozone levels are expected to increase strongly. The per capita MPI (PCMPI), which combines demographic and pollutants concentrations projections, shows that a rapidly increasing number of people worldwide will experience reduced air quality during the first half of the 21st century. Following the business as usual scenario, it is projected that air quality for the global average

  7. EFFECT OF LASER LIGHT ON LASER PLASMAS: Laser plasma at low air pressure

    NASA Astrophysics Data System (ADS)

    Vas'kovskiĭ, Yu M.; Moiseev, V. N.; Rovinskiĭ, R. E.; Tsenina, I. S.

    1993-01-01

    The dynamic and optical characteristics of the laser plasma produced during the application of a CO2 laser pulse to a target have been studied as a function of the ambient air pressure. The changes in the surface roughness of the sample after bombardment were studied as a function of the air pressure. It is concluded from the results that a transition from an air plasma to an erosion plasma occurs at a residual air pressure on the order of 1 torr. The experiment data support the existing picture of the process by which a plasma is produced near the surface of a target in air by laser pulses.

  8. Effects of burstiness on the air transportation system

    NASA Astrophysics Data System (ADS)

    Ito, Hidetaka; Nishinari, Katsuhiro

    2017-01-01

    The effects of burstiness in complex networks have received considerable attention. In particular, the effects on temporal distance and delays in the air transportation system are significant owing to their huge impact on our society. Therefore, in this paper, the temporal distance of empirical U.S. flight schedule data is compared with that of regularized data without burstiness to analyze the effects of burstiness. The temporal distance is calculated by a graph analysis method considering flight delays, missed connections, flight cancellations, and congestion. In addition, we propose two temporal distance indexes based on passengers' behavior to quantify the effects. As a result, we find that burstiness reduces both the scheduled and the actual temporal distances for business travelers, while delays caused by missed connections and congestion are increased. We also find that the decrease of the scheduled temporal distance by burstiness is offset by an increase of the delays for leisure passengers. Moreover, we discover that the positive effect of burstiness is lost when flight schedules are overcrowded.

  9. Effects of environmental change on wildlife health

    PubMed Central

    Acevedo-Whitehouse, Karina; Duffus, Amanda L. J.

    2009-01-01

    Environmental change has negatively affected most biological systems on our planet and is becoming of increasing concern for the well-being and survival of many species. At an organism level, effects encompass not only endocrine disruptions, sex-ratio changes and decreased reproductive parameters, but also include teratogenic and genotoxic effects, immunosuppression and other immune-system impairments that can lead directly to disease or increase the risk of acquiring disease. Living organisms will strive to maintain health by recognizing and resolving abnormal situations, such as the presence of invading microorganisms or harmful peptides, abnormal cell replication and deleterious mutations. However, fast-paced environmental changes may pose additional pressure on immunocompetence and health maintenance, which may seriously impact population viability and persistence. Here, we outline the importance of a functional immune system for survival and examine the effects that exposure to a rapidly changing environment might exert on immunocompetence. We then address the various levels at which anthropogenic environmental change might affect wildlife health and identify potential deficits in reproductive parameters that might arise owing to new immune challenges in the context of a rapidly changing environment. Throughout the paper, a series of examples and case studies are used to illustrate the impact of environmental change on wildlife health. PMID:19833653

  10. Air Force Training: Further Analysis and Planning Needed to Improve Effectiveness

    DTIC Science & Technology

    2016-09-01

    explained that Red Flag exercises require a significant adversary air presence to provide high quality training for the participants. As discussed... AIR FORCE TRAINING Further Analysis and Planning Needed to Improve Effectiveness Report to Congressional Committees...GAO-16-864, a report to congressional committees September 2016 AIR FORCE TRAINING Further Analysis and Planning Needed to Improve

  11. THE EFFECTS OF BUILDING FEATURES ON INDOOR AIR AND POLLUTANT MOVEMENTS

    EPA Science Inventory

    The paper discusses full-scale residential building tests to determine the effects of building features on indoor air and pollutant movement. It was found that the activated heating and air-conditioning (HAC) system served as a conductor that enhanced the indoor air movement and ...

  12. Effect of wind tunnel air velocity on VOC flux rates from CAFO manure and wastewater

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wind tunnels and flux chambers are often used to estimate volatile organic compound (VOC) emissions from animal feeding operations (AFOs) without regard to air velocity or sweep air flow rates. Laboratory experiments were conducted to evaluate the effect of wind tunnel air velocity on VOC emission ...

  13. Air Pollution and Its Effects on an Individual's Health and Exercise Performance.

    ERIC Educational Resources Information Center

    Singh, A. I. Clifford

    1988-01-01

    Air Pollution is a common environmental stressor affecting the training and competitive performance of athletes, commonly irritating the eyes, nose, and throat. The health and exercise effects of such primary and secondary air pollutants as carbon monoxide, sulfur dioxide, air particulates, ozone, and nitrogen dioxide are discussed. (CB)

  14. Effect of air on energy and rise-time spectra measured by proportional gas counter

    SciTech Connect

    Kawano, T.; Tanaka, M.; Isozumi, S.; Isozumi, Y.; Tosaki, M.; Sugiyama, T.

    2015-03-15

    Air exerts a negative effect on radiation detection using a gas counter because oxygen contained in air has a high electron attachment coefficient and can trap electrons from electron-ion pairs created by ionization from incident radiation in counting gas. This reduces radiation counts. The present study examined the influence of air on energy and rise-time spectra measurements using a proportional gas counter. In addition, a decompression procedure method was proposed to reduce the influence of air and its effectiveness was investigated. For the decompression procedure, the counting gas inside the gas counter was decompressed below atmospheric pressure before radiation detection. For the spectrum measurement, methane as well as various methane and air mixtures were used as the counting gas to determine the effect of air on energy and rise-time spectra. Results showed that the decompression procedure was effective for reducing or eliminating the influence of air on spectra measurement using a proportional gas counter. (authors)

  15. Passenger aircraft cabin air quality: trends, effects, societal costs, proposals.

    PubMed

    Hocking, M B

    2000-08-01

    As aircraft operators have sought to substantially reduce propulsion fuel cost by flying at higher altitudes, the energy cost of providing adequate outside air for ventilation has increased. This has lead to a significant decrease in the amount of outside air provided to the passenger cabin, partly compensated for by recirculation of filtered cabin air. The purpose of this review paper is to assemble the available measured air quality data and some calculated estimates of the air quality for aircraft passenger cabins to highlight the trend of the last 25 years. The influence of filter efficiencies on air quality, and a few medically documented and anecdotal cases of illness transmission aboard aircraft are discussed. Cost information has been collected from the perspective of both the airlines and passengers. Suggestions for air quality improvement are given which should help to result in a net, multistakeholder savings and improved passenger comfort.

  16. Determination of the effect of transfer between vacuum and air on mass standards of platinum-iridium and stainless steel

    NASA Astrophysics Data System (ADS)

    Davidson, Stuart

    2010-08-01

    This paper reports work undertaken to assess the change in the mass values of stainless steel and platinum-iridium weights transferred between air and vacuum and to determine the repeatability of this change. Sets of kilogram transfer standards, manufactured from stainless steel and platinum-iridium and with different surface areas, were used to determine the effect of transfer between air and vacuum on the values of the mass standards. The SI unit of mass is the only unit of the seven base SI quantities which is still defined in terms of an artefact rather than by relation to a fundamental physical constant. Work is underway to identify a means of deriving the SI unit of mass from fundamental constants and at present the two principal approaches are the International Avogadro Coordination and the watt balance projects. Both of these approaches involve realizing a kilogram in vacuum and therefore the traceability from a kilogram realized in vacuum to mass standards in air is crucial to the effective dissemination of the mass scale. The work reported here characterizes the changes in mass values of standards on transfer between air and vacuum and thus will enable traceability to be established for an in-air mass scale based on a definition of the unit in vacuum.

  17. Volcanic gas emissions and their effect on ambient air character

    SciTech Connect

    Sutton, A.J.; Elias, T.

    1994-01-01

    This bibliography was assembled to service an agreement between Department of Energy and the USGS to provide a body of references and useful annotations for understanding background gas emissions from Kilauea volcano. The current East Rift Zone (ERZ) eruption of Kilauea releases as much as 500,000 metric tonnes of SO{sub 2} annually, along with lesser amounts of other chemically and radiatively active species including H{sub 2}S, HCl, and HF. Primary degassing locations on Kilauea are located in the summit caldera and along the middle ERZ. The effects of these emissions on ambient air character are a complex function of chemical reactivity, source geometry and effusivity, and local meteorology. Because of this complexity, we organized the bibliography into three main sections: (1) characterizing gases as they leave the edifice; (2) characterizing gases and chemical reaction products away from degassing sources; and (3) Hawaii Island meteorology.

  18. Assessing Resistance to Change During Shifting from Legacy to Open Web-Based Systems in the Air Transport Industry

    NASA Astrophysics Data System (ADS)

    Brewer, Denise

    The air transport industry (ATI) is a dynamic, communal, international, and intercultural environment in which the daily operations of airlines, airports, and service providers are dependent on information technology (IT). Many of the IT legacy systems are more than 30 years old, and current regulations and the globally distributed workplace have brought profound changes to the way the ATI community interacts. The purpose of the study was to identify the areas of resistance to change in the ATI community and the corresponding factors in change management requirements that minimize product development delays and lead to a successful and timely shift from legacy to open web-based systems in upgrading ATI operations. The research questions centered on product development team processes as well as the members' perceived need for acceptance of change. A qualitative case study approach rooted in complexity theory was employed using a single case of an intercultural product development team dispersed globally. Qualitative data gathered from questionnaires were organized using Nvivo software, which coded the words and themes. Once coded, themes emerged identifying the areas of resistance within the product development team. Results of follow-up interviews with team members suggests that intercultural relationship building prior to and during project execution; focus on common team goals; and, development of relationships to enhance interpersonal respect, understanding and overall communication help overcome resistance to change. Positive social change in the form of intercultural group effectiveness evidenced in increased team functioning during major project transitions is likely to result when global managers devote time to cultural understanding.

  19. Effects of Group Support Systems on United States Air Force Strategic Planning Efforts

    DTIC Science & Technology

    1998-09-01

    Strategic planning at an Air Force wing is a team based activity that offers many advantages to the Air Force. But, it is clear there are still...questions about how to properly conduct strategic planning to produce the highest quality plans in the most effective and efficient manner. To answer this...question, the Air Force created a research project aimed at discovering new methods to improve strategic planning at Air Force wing levels using a

  20. Short-term effects of daily air pollution on mortality

    NASA Astrophysics Data System (ADS)

    Wan Mahiyuddin, Wan Rozita; Sahani, Mazrura; Aripin, Rasimah; Latif, Mohd Talib; Thach, Thuan-Quoc; Wong, Chit-Ming

    2013-02-01

    The daily variations of air pollutants in the Klang Valley, Malaysia, which includes Kuala Lumpur were investigated for its association with mortality counts using time series analysis. This study located in the tropic with much less seasonal variation than typically seen in more temperate climates. Data on daily mortality for the Klang Valley (2000-2006), daily mean concentrations of air pollutants of PM10, SO2, CO, NO2, O3, daily maximum O3 and meteorological conditions were obtained from Malaysian Department of Environment. We examined the association between pollutants and daily mortality using Poisson regression while controlling for time trends and meteorological factors. Effects of the pollutants (Relative Risk, RR) on current-day (lag 0) mortality to seven previous days (lag 7) and the effects of the pollutants from the first two days (lag 01) to the first eight days (lag 07) were determined. We found significant associations in the single-pollutant model for PM10 and the daily mean O3 with natural mortality. For the daily mean O3, the highest association was at lag 05 (RR = 1.0215, 95% CI = 1.0013-1.0202). CO was found not significantly associated with natural mortality, however the RR's of CO were found to be consistently higher than PM10. In spite of significant results of PM10, the magnitude of RR's of PM10 was not important for natural mortality in comparison with either daily mean O3 or CO. There is an association between daily mean O3 and natural mortality in a two-pollutants model after adjusting for PM10. Most pollutants except SO2, were significantly associated with respiratory mortality in a single pollutant model. Daily mean O3 is also important for respiratory mortality, with over 10% of mortality associated with every IQR increased. These findings are noteworthy because seasonal confounding is unlikely in this relatively stable climate, by contrast with more temperate regions.

  1. Energy and air emission effects of water supply.

    PubMed

    Stokes, Jennifer R; Horvath, Arpad

    2009-04-15

    Life-cycle air emission effects of supplying water are explored using a hybrid life-cycle assessment For the typically sized U.S. utility analyzed, recycled water is preferable to desalination and comparable to importation. Seawater desalination has an energy and air emission footprint that is 1.5-2.4 times larger than that of imported water. However, some desalination modes fare better; brackish groundwater is 53-66% as environmentally intensive as seawater desalination. The annual water needs (326 m3) of a typical Californian that is met with imported water requires 5.8 GJ of energy and creates 360 kg of CO2 equivalent emissions. With seawater desalination, energy use would increase to 14 GJ and 800 kg of CO2 equivalent emissions. Meeting the water demand of California with desalination would consume 52% of the state's electricity. Supply options were reassessed using alternative electricity mixes, including the average mix of the United States and several renewable sources. Desalination using solar thermal energy has lower greenhouse gas emissions than that of imported and recycled water (using California's electricity mix), but using the U.S. mix increases the environmental footprint by 1.5 times. A comparison with a more energy-intensive international scenario shows that CO2 equivalent emissions for desalination in Dubai are 1.6 times larger than in California. The methods, decision support tool (WEST), and results of this study should persuade decision makers to make informed water policy choices by including energy consumption and material use effects in the decision-making process.

  2. Climate change effects on hydroecology of arctic freshwater ecosystems.

    PubMed

    Prowse, Terry D; Wrona, Frederick J; Reist, James D; Gibson, John J; Hobbie, John E; Lévesque, Lucie M J; Vincent, Warwick F

    2006-11-01

    In general, the arctic freshwater-terrestrial system will warm more rapidly than the global average, particularly during the autumn and winter season. The decline or loss of many cryospheric components and a shift from a nival to an increasingly pluvial system will produce numerous physical effects on freshwater ecosystems. Of particular note will be reductions in the dominance of the spring freshet and changes in the intensity of river-ice breakup. Increased evaporation/evapotranspiration due to longer ice-free seasons, higher air/water temperatures and greater transpiring vegetation along with increase infiltration because of permafrost thaw will decrease surface water levels and coverage. Loss of ice and permafrost, increased water temperatures and vegetation shifts will alter water chemistry, the general result being an increase in lotic and lentic productivity. Changes in ice and water flow/levels will lead to regime-specific increases and decreases in habitat availability/quality across the circumpolar Arctic.

  3. DYNAMIC EVALUATION OF REGIONAL AIR QUALITY MODELS: ASSESSING CHANGES TO O 3 STEMMING FROM CHANGES IN EMISSIONS AND METEOROLOGY

    EPA Science Inventory

    Regional-scale air quality models are used to estimate the response of air pollutants to potential emission control strategies as part of the decision-making process. Traditionally, the model predicted pollutant concentrations are evaluated for the “base case” to assess a model’s...

  4. Creating Effective Dialogue Around Climate Change

    NASA Astrophysics Data System (ADS)

    Kiehl, J. T.

    2015-12-01

    Communicating climate change to people from diverse sectors of society has proven to be difficult in the United States. It is widely recognized that difficulties arise from a number of sources, including: basic science understanding, the psychologically affect laden content surrounding climate change, and the diversity of value systems that exist in our society. I explore ways of working with the affect that arises around climate change and describe specific methods to work with the resistance often encountered when communicating this important issue. The techniques I describe are rooted in psychology and group process and provide means for creating more effective narratives to break through the barriers to communicating climate change science. Examples are given from personal experiences in presenting climate change to diverse groups.

  5. Air pollution and blood lipid markers levels: Estimating short and long-term effects on elderly hypertension inpatients complicated with or without type 2 diabetes.

    PubMed

    Xiao, Sanhua; Liu, Ranran; Wei, Youxiu; Feng, Lin; Lv, Xuemin; Tang, Fei

    2016-08-01

    With the development of society and the economy, many Chinese cities are shrouded in pollution haze for much of the year. Scientific studies have identified various adverse effects of air pollutants on human beings. However, the relationships between air pollution and blood lipid levels are still unclear. The objective of this study is to explore the short and long-term effects of air pollution on eight blood lipid markers among elderly hypertension inpatients complicated with or without type 2 diabetes (T2D). Blood lipid markers which met the pre-established inclusion criteria were exported from the medical record system. Air pollution data were acquired from the official environmental protection website. Associations between the air quality index and the blood lipid indexes were analyzed by one-way ANOVA and further Bonferroni correction. In an exposure time of 7 days or longer, blood lipid markers were somewhat affected by poor air quality. However, the results could not predict whether atherosclerosis would be promoted or inhibited by poorer air condition. Changes of blood lipid markers of hypertension inpatients with or without T2D were not completely the same, but no blood lipid markers had an opposite trend between the two populations. The air quality index was associated with changes to blood lipid markers to some extent in a population of hypertension inpatients with or without T2D. Further studies are needed to investigate the potential mechanism by which air pollutants induce blood lipids changes.

  6. Change in strategy of solving psychological tests: evidence of nitrogen narcosis in shallow air-diving.

    PubMed

    Petri, N M

    2003-01-01

    The depths from 10 to 30 m are usually not considered narcotic in scuba air-diving, and evidence of psychomotor disturbances attributable to nitrogen narcosis at these depths is weak and contradictory. 15 experienced male divers were tested in a chamber at 1, 2, 3, and 4 bars over five consecutive days using a battery of computer generated psychological tests-Computerized Reactionmeter Drenovac (CRD-series). Total test solving time, minimal single task solving time, total "ballast" time, and total number of errors were recorded. Nitrogen narcosis effects were evident at all hyperbaric pressures with marked performance differences among subjects. MANOVA revealed significant effects of nitrogen partial pressure for groups of the same variables as follows: total test solving time (p < 0.001), total "ballast" time (p < 0.001), and total number of errors (p = 0.038), but not for minimal single task solving time. ANOVA showed significant effects of pressure only on tests of visual discrimination of signal location (total test solving time: p = 0.012, total "ballast" time: p < 0.001), simple convergent visual orientation (total test solving time: p = 0.012), and convergent thinking (total test solving time: p = 0.002, total number of errors: p = 0.049). The order of the pressure exposures had no influence on subject performance. Impaired psychomotor processing found during air exposures from 2 to 4 bars suggests that nitrogen narcosis at depths usually considered safe from its effects might be a problem in underwater operations that require accuracy, speed, limited time of performance, and complex psychomotor skills.

  7. Aire Downregulation Is Associated with Changes in the Posttranscriptional Control of Peripheral Tissue Antigens in Medullary Thymic Epithelial Cells

    PubMed Central

    Oliveira, Ernna H.; Macedo, Claudia; Collares, Cristhianna V.; Freitas, Ana Carolina; Donate, Paula Barbim; Sakamoto-Hojo, Elza T.; Donadi, Eduardo A.; Passos, Geraldo A.

    2016-01-01

    Autoimmune regulator (Aire) is a transcriptional regulator of peripheral tissue antigens (PTAs) and microRNAs (miRNAs) in medullary thymic epithelial cells (mTECs). In this study, we tested the hypothesis that Aire also played a role as an upstream posttranscriptional controller in these cells and that variation in its expression might be associated with changes in the interactions between miRNAs and the mRNAs encoding PTAs. We demonstrated that downregulation of Aire in vivo in the thymuses of BALB/c mice imbalanced the large-scale expression of these two RNA species and consequently their interactions. The expression profiles of a large set of mTEC miRNAs and mRNAs isolated from the thymuses of mice subjected (or not) to small-interfering-induced Aire gene knockdown revealed that 87 miRNAs and 4,558 mRNAs were differentially expressed. The reconstruction of the miRNA–mRNA interaction networks demonstrated that interactions between these RNAs were under Aire influence and therefore changed when this gene was downregulated. Prior to Aire-knockdown, only members of the miR-let-7 family interacted with a set of PTA mRNAs. Under Aire-knockdown conditions, a larger set of miRNA families and their members established this type of interaction. Notably, no previously described Aire-dependent PTA interacted with the miRNAs, indicating that these PTAs were somehow refractory. The miRNA–mRNA interactions were validated by calculating the minimal free energy of the pairings between the miRNA seed regions and the mRNA 3′ UTRs and within the cellular milieu using the luciferase reporter gene assay. These results suggest the existence of a link between transcriptional and posttranscriptional control because Aire downregulation alters the miRNA–mRNA network controlling PTAs in mTEC cells. PMID:27933063

  8. An air/sea flux model including the effects of capillary waves

    NASA Technical Reports Server (NTRS)

    Bourassa, Mark A.

    1993-01-01

    An improved model of the air/sea interface is developed. The improvements consist in including the effect of capillary (surface tension) waves on the tropical surface fluxes and the consideration of the sea state, both of which increase the magnitude of tropical surface fluxes. Changes in surface stress are most significant in the low wind-speed regions, which include the areas where westerly bursts occur. It is shown that the changes, from the regular wind conditions to those of a westerly burst or El-Nino, can double when the effects of capillary waves are considered. This implies a much stronger coupling between the ocean and the atmosphere than is predicted by other boundary layer models.

  9. EXAMINING THE IMPACT OF CLIMATE CHANGE AND VARIABILITY OF REGIONAL AIR QUALITY OVER THE UNITED STATES

    EPA Science Inventory

    The United States has established a series of standards for criteria and other air pollutants to safeguard air quality to protect human health and the environment. The Climate Impact on Regional Air Quality (CIRAQ) project, a collaborative research effort involving multiple Fede...

  10. How Can Urban Policies Improve Air Quality and Help Mitigate Global Climate Change: a Systematic Mapping Review.

    PubMed

    Slovic, Anne Dorothée; de Oliveira, Maria Aparecida; Biehl, João; Ribeiro, Helena

    2016-02-01

    Tackling climate change at the global level is central to a growing field of scientific research on topics such as environmental health, disease burden, and its resulting economic impacts. At the local level, cities constitute an important hub of atmospheric pollution due to the large amount of pollutants that they emit. As the world population shifts to urban centers, cities will increasingly concentrate more exposed populations. Yet, there is still significant progress to be made in understanding the contribution of urban pollutants other than CO2, such as vehicle emissions, to global climate change. It is therefore particularly important to study how local governments are managing urban air pollution. This paper presents an overview of local air pollution control policies and programs that aim to reduce air pollution levels in megacities. It also presents evidence measuring their efficacy. The paper argues that local air pollution policies are not only beneficial for cities but are also important for mitigating and adapting to global climate change. The results systematize several policy approaches used around the world and suggest the need for more in-depth cross-city studies with the potential to highlight best practices both locally and globally. Finally, it calls for the inclusion of a more human rights-based approach as a mean of guaranteeing of clean air for all and reducing factors that exacerbate climate change.

  11. Air Pollution–Associated Changes in Lung Function among Asthmatic Children in Detroit

    PubMed Central

    Lewis, Toby C.; Robins, Thomas G.; Dvonch, J. Timothy; Keeler, Gerald J.; Yip, Fuyuen Y.; Mentz, Graciela B.; Lin, Xihong; Parker, Edith A.; Israel, Barbara A.; Gonzalez, Linda; Hill, Yolanda

    2005-01-01

    In a longitudinal cohort study of primary-school–age children with asthma in Detroit, Michigan, we examined relationships between lung function and ambient levels of particulate matter ≤ 10 μm and ≤ 2.5 μm in diameter (PM10 and PM2.5) and ozone at varying lag intervals using generalized estimating equations. Models considered effect modification by maintenance corticosteroid (CS) use and by the presence of an upper respiratory infection (URI) as recorded in a daily diary among 86 children who participated in six 2-week seasonal assessments from winter 2001 through spring 2002. Participants were predominantly African American from families with low income, and > 75% were categorized as having persistent asthma. In both single-pollutant and two-pollutant models, many regressions demonstrated associations between higher exposure to ambient pollutants and poorer lung function (increased diurnal variability and decreased lowest daily values for forced expiratory volume in 1 sec) among children using CSs but not among those not using CSs, and among children reporting URI symptoms but not among those who did not report URIs. Our findings suggest that levels of air pollutants in Detroit, which are above the current National Ambient Air Quality Standards, adversely affect lung function of susceptible asthmatic children. PMID:16079081

  12. Effect of the accumulation of polycyclic aromatic hydrocarbons in the sea surface microlayer on their coastal air-sea exchanges

    NASA Astrophysics Data System (ADS)

    Guitart, C.; García-Flor, N.; Miquel, J. C.; Fowler, S. W.; Albaigés, J.

    2010-01-01

    Several measurements of polycyclic aromatic hydrocarbons (PAHs) in coastal marine compartments (viz. atmosphere, sea surface microlayer, subsurface seawater, sinking particles and sediments), made nearly simultaneously at two stations in the north-eastern Mediterranean, were used to estimate the transport fluxes of individual and total PAHs through the air-seawater-sediment system. Diffusive air-sea exchange fluxes were estimated using both subsurface water (SSW) and sea surface microlayer (SML) concentrations. The air-SML fluxes ranged from 411 to 12,292 ng m - 2 d - 1 (absorption) and from - 506 to -13,746 ng m - 2 d - 1 (volatilisation) for total PAHs (Σ15). Air-seawater column transport of particle-associated PAHs was estimated from the analysis of particulate atmospheric and sediment interceptor trap materials. Air-sea particle deposition fluxes of total PAHs ranged from 13 to 114 ng m - 2 d - 1 and seawater particle settling fluxes (upper 5 m water column) ranged from 184 to 323 ng m - 2 d - 1 . The results of this study indicate that both the magnitude and the direction of the calculated air-sea diffusive fluxes change when PAH concentrations in the SML are considered. As a result, PAHs accumulation in the SML could produce the so-called "flux capping effect". However, the high variability in the coastal air-sea PAHs flux estimations, mainly due to the parameters uncertainty, requires further experimental approaches, including improvement of parameterisations.

  13. Strain-induced extinction of hydrogen-air counterflow diffusion flames - Effects of steam, CO2, N2, and O2 additives to air

    NASA Technical Reports Server (NTRS)

    Pellett, G. L.; Northam, G. B.; Wilson, L. G.

    1992-01-01

    A fundamental study was performed using axisymmetric nozzle and tubular opposed jet burners to measure the effects of laminar plug flow and parabolic input velocity profiles on the extinction limits of H2-air counterflow diffusion flames. Extinction limits were quantified by 'flame strength', (average axial air jet velocity) at blowoff of the central flame. The effects of key air contaminants, on the extinction limits, are characterized and analyzed relative to utilization of combustion contaminated vitiated air in high enthalpy supersonic test facilities.

  14. Air pollution and detrimental effects on children's brain. The need for a multidisciplinary approach to the issue complexity and challenges.

    PubMed

    Calderón-Garcidueñas, Lilian; Torres-Jardón, Ricardo; Kulesza, Randy J; Park, Su-Bin; D'Angiulli, Amedeo

    2014-01-01

    Millions of children in polluted cities are showing brain detrimental effects. Urban children exhibit brain structural and volumetric abnormalities, systemic inflammation, olfactory, auditory, vestibular and cognitive deficits v low-pollution controls. Neuroinflammation and blood-brain-barrier (BBB) breakdown target the olfactory bulb, prefrontal cortex and brainstem, but are diffusely present throughout the brain. Urban adolescent Apolipoprotein E4 carriers significantly accelerate Alzheimer pathology. Neurocognitive effects of air pollution are substantial, apparent across all populations, and potentially clinically relevant as early evidence of evolving neurodegenerative changes. The diffuse nature of the neuroinflammation and neurodegeneration forces to employ a weight of evidence approach incorporating current clinical, cognitive, neurophysiological, radiological and epidemiological research. Pediatric air pollution research requires extensive multidisciplinary collaborations to accomplish a critical goal: to protect exposed children through multidimensional interventions having both broad impact and reach. Protecting children and teens from neural effects of air pollution should be of pressing importance for public health.

  15. Investigating the urban heat island effect on air quality

    NASA Astrophysics Data System (ADS)

    Loughner, C. P.; Allen, D. J.; Dickerson, R. R.; Pickering, K. E.; Shou, Y.; Zhang, D.

    2009-12-01

    Urbanization impacts meteorology and air quality in and downwind of cities. An urban heat island can increase the temperature in and downwind of cities. An increase in temperature may worsen air quality by increasing the amount of photochemically produced ozone. During an air pollution episode on July 9, 2007, in which 8-hour maximum ozone and 24-hour average PM2.5 concentrations reached 125ppb and 40μg/m3 respectively, the Washington, DC urban heat island propagated downwind over Columbia, MD and then Baltimore, MD further amplifying the temperature in and downwind of Baltimore. With the use of the Weather Research and Forecasting model coupled with an urban canopy model (WRF/UCM) and EPA’s Community Multi-scale Air Quality (CMAQ) model, the air quality is analyzed within the urban heat island. In addition, the interactions between the Chesapeake Bay breeze, the urban heat island, and the air chemistry are analyzed.

  16. Positive and negative ions by air purifier have no effects on embryo-fetal development in rats.

    PubMed

    Yamamoto, Dai; Wako, Kiyoshi; Sato, Yukari; Fujishiro, Mayumi; Matsuura, Ikuo; Ohnishi, Yasuyuki

    2014-06-01

    Air purifiers, which release positive and negative ions generated by an electric discharge into the air, have been widely used in common households. In this study, the developmental toxicity potential of the ionized air containing positive and negative ions was evaluated in SD rats [Crl:CD(SD)] following whole-body inhalation to obtain preliminary information for the definitive study. Two groups of 10 pregnant female rats were exposed to the ionized air at concentrations of 0 and 7,000,000 ions/cm(3) for 6 hr per day from Days 6 to 19 of gestation. All dams underwent a cesarean section on Day 20 of gestation and their fetuses were examined externally, viscerally, and skeletally for morphological changes. The ionized air had no effects on dams in terms of clinical signs, body weight, food consumption, gravid uterine weights, corrected body weight by gravid uterine weight, or necropsy findings. In addition, there were no effects on the maintenance of pregnancy, including abortion or premature delivery. No exposure-related changes were detected in the number of corpora lutea, implantations, dead embryos, or live fetuses, implantation loss, live fetal weights, sex ratio, or placental weight or features. Fetal examination revealed no external, visceral, or skeletal anomalies or variations caused by the ionized air, nor were there any changes in degree of ossification. Although this study did not fully adhere to the current guidelines because of a smaller number of animals per group, it was suggested that the ionized air has no maternal toxicity or embryo-fetal toxicity in rats.

  17. Effect of VOC emissions from vegetation on urban air quality during hot periods

    NASA Astrophysics Data System (ADS)

    Churkina, Galina; Kuik, Friderike; Bonn, Boris; Lauer, Axel; Grote, Ruediger; Butler, Tim

    2016-04-01

    Programs to plant millions of trees in cities around the world aim at the reduction of summer temperatures, increase of carbon storage, storm water control, and recreational space, as well as at poverty alleviation. These urban greening programs, however, do not take into account how closely human and natural systems are coupled in urban areas. Compared with the surroundings of cities, elevated temperatures together with high anthropogenic emissions of air and water pollutants are quite typical in urban systems. Urban and sub-urban vegetation respond to changes in meteorology and air quality and can react to pollutants. Neglecting this coupling may lead to unforeseen negative effects on air quality resulting from urban greening programs. The potential of emissions of volatile organic compounds (VOC) from vegetation combined with anthropogenic emissions of air pollutants to produce ozone has long been recognized. This ozone formation potential increases under rising temperatures. Here we investigate how emissions of VOC from urban vegetation affect corresponding ground-level ozone and PM10 concentrations in summer and especially during heat wave periods. We use the Weather Research and Forecasting Model with coupled atmospheric chemistry (WRF-CHEM) to quantify these feedbacks in the Berlin-Brandenburg region, Germany during the two summers of 2006 (heat wave) and 2014 (reference period). VOC emissions from vegetation are calculated by MEGAN 2.0 coupled online with WRF-CHEM. Our preliminary results indicate that the contribution of VOCs from vegetation to ozone formation may increase by more than twofold during heat wave periods. We highlight the importance of the vegetation for urban areas in the context of a changing climate and discuss potential tradeoffs of urban greening programs.

  18. Cleaning up the air: effectiveness of air quality policy for SO2 and NOx emissions in China

    NASA Astrophysics Data System (ADS)

    van der A, Ronald J.; Mijling, Bas; Ding, Jieying; Elissavet Koukouli, Maria; Liu, Fei; Li, Qing; Mao, Huiqin; Theys, Nicolas

    2017-02-01

    Air quality observations by satellite instruments are global and have a regular temporal resolution, which makes them very useful in studying long-term trends in atmospheric species. To monitor air quality trends in China for the period 2005-2015, we derive SO2 columns and NOx emissions on a provincial level with improved accuracy. To put these trends into perspective they are compared with public data on energy consumption and the environmental policies of China. We distinguish the effect of air quality regulations from economic growth by comparing them relatively to fossil fuel consumption. Pollutant levels, per unit of fossil fuel, are used to assess the effectiveness of air quality regulations. We note that the desulfurization regulations enforced in 2005-2006 only had a significant effect in the years 2008-2009, when a much stricter control of the actual use of the installations began. For national NOx emissions a distinct decreasing trend is only visible from 2012 onwards, but the emission peak year differs from province to province. Unlike SO2, emissions of NOx are highly related to traffic. Furthermore, regulations for NOx emissions are partly decided on a provincial level. The last 3 years show a reduction both in SO2 and NOx emissions per fossil fuel unit, since the authorities have implemented several new environmental regulations. Despite an increasing fossil fuel consumption and a growing transport sector, the effects of air quality policy in China are clearly visible. Without the air quality regulations the concentration of SO2 would be about 2.5 times higher and the NO2 concentrations would be at least 25 % higher than they are today in China.

  19. Evaluating the Effectiveness of Air Force Foundational Cyberspace Training

    DTIC Science & Technology

    2012-06-14

    is contagious and his passion for both cyberspace and the Air Force provided continual motivation. viii Table of Contents Page Abstract...while the others enter a wide variety of Air Force specialties. The USAFA cyber training program was developed in coordination with Air University...commissioned more than 1,796 second lieutenants who entered active duty [8]. ROTC cadets receive two hours of instruction via lecture and guided

  20. Climate Effects of Global Land Cover Change

    SciTech Connect

    Gibbard, S G; Caldeira, K; Bala, G; Phillips, T; Wickett, M

    2005-08-24

    There are two competing effects of global land cover change on climate: an albedo effect which leads to heating when changing from grass/croplands to forest, and an evapotranspiration effect which tends to produce cooling. It is not clear which effect would dominate in a global land cover change scenario. We have performed coupled land/ocean/atmosphere simulations of global land cover change using the NCAR CAM3 atmospheric general circulation model. We find that replacement of current vegetation by trees on a global basis would lead to a global annual mean warming of 1.6 C, nearly 75% of the warming produced under a doubled CO{sub 2} concentration, while global replacement by grasslands would result in a cooling of 0.4 C. These results suggest that more research is necessary before forest carbon storage should be deployed as a mitigation strategy for global warming. In particular, high latitude forests probably have a net warming effect on the Earth's climate.

  1. Effect of air sparging on fate and transport of trichloroethylene in chambers with alfalfa plants

    SciTech Connect

    Zhang, Q.; Hu, J.; Erickson, L.E.; Davis, L.C.

    1997-12-31

    To study the effect of air sparging in soil with trichloroethylene present as a dense nonaqueous phase, air was supplied through pipes installed at the bottom of two chambers planted with alfalfa. Air input rate was 2.14 L/m{sup 2}/day. The fate of trichloroethylene (TCE) was investigated by monitoring TCE concentration in both outflow groundwater and soil gas. Comparison of these results with those of the previous study without air sparging indicates that air sparging appreciably increases the groundwater concentration of TCE. The soil gas at the surface shows even greater concentration difference. The flux of TCE to the atmosphere is increased significantly by air input. Accordingly, the authors can conclude that air sparging improved mass transfer of TCE from the nonaqueous phase to groundwater phase. Air sparging appeared to negatively impact the health of the alfalfa because of the elevated TCE present in the vadose zone of the chamber.

  2. Effect of fireworks on ambient air quality in Malta

    NASA Astrophysics Data System (ADS)

    Camilleri, Renato; Vella, Alfred J.

    2010-11-01

    Religious festivals ( festas) in the densely populated Maltese archipelago (Central Mediterranean) are ubiquitous during summer when 86 of them are celebrated between June and October, each involving the burning of fireworks both in ground and aerial displays over a period of 3 days or longer per festival. We assessed the effect of fireworks on the air quality by comparing PM 10 and its content of Al, Ba, Cu, Sr and Sb which materials are used in pyrotechnic compositions. PM 10 was collected mainly from two sites, one in Malta (an urban background site) and the other in Gozo (a rural site) during July-August 2005 when 59 feasts were celebrated and September-October 2005 when only 11 feasts occurred. For both Malta and Gozo, PM 10 and metal concentration levels measured as weekly means were significantly higher during July-August compared to September-October and there exist strong correlations between PM 10 and total metal content. Additionally, for Malta dust, Al, Ba, Cu and Sr correlated strongly with each other and also with total concentration of all five metals. The same parameters measured in April 2006 in Malta were at levels similar to those found in the previous October. Ba and Sb in dust from the urban background site in Malta during July-August were at comparable or higher concentration than recently reported values in PM 10 from a heavily-trafficked London road and this suggests that these metals are locally not dominated by sources from roadside materials such as break liner wear but more likely by particulate waste from fireworks. Our findings point to the fact that festa firework displays contribute significantly and for a prolonged period every year to airborne dust in Malta where PM 10 is an intractable air quality concern. The presence in this dust of elevated levels of Ba and especially Sb, a possible carcinogen, is of concern to health.

  3. Impacts of Ozone-vegetation Interactions and Biogeochemical Feedbacks on Atmospheric Composition and Air Quality Under Climate Change

    NASA Astrophysics Data System (ADS)

    Sadeke, M.; Tai, A. P. K.; Lombardozzi, D.; Val Martin, M.

    2015-12-01

    Surface ozone pollution is one of the major environmental concerns due to its damaging effects on human and vegetation. One of the largest uncertainties of future surface ozone prediction comes from its interaction with vegetation under a changing climate. Ozone can be modulated by vegetation through, e.g., biogenic emissions, dry deposition and transpiration. These processes are in turn affected by chronic exposure to ozone via lowered photosynthesis rate and stomatal conductance. Both ozone and vegetation growth are expected to be altered by climate change. To better understand these climate-ozone-vegetation interactions and possible feedbacks on ozone itself via vegetation, we implement an online ozone-vegetation scheme [Lombardozzi et al., 2015] into the Community Earth System Model (CESM) with active atmospheric chemistry, climate and land surface components. Previous overestimation of surface ozone in eastern US, Canada and Europe is shown to be reduced by >8 ppb, reflecting improved model-observation comparison. Simulated surface ozone is lower by 3.7 ppb on average globally. Such reductions (and improvements) in simulated ozone are caused mainly by lower isoprene emission arising from reduced leaf area index in response to chronic ozone exposure. Effects via transpiration are also potentially significant but require better characterization. Such findings suggest that ozone-vegetation interaction may substantially alter future ozone simulations, especially under changing climate and ambient CO2 levels, which would further modulate ozone-vegetation interactions. Inclusion of such interactions in Earth system models is thus necessary to give more realistic estimation and prediction of surface ozone. This is crucial for better policy formulation regarding air quality, land use and climate change mitigation. Reference list: Lombardozzi, D., et al. "The Influence of Chronic Ozone Exposure on Global Carbon and Water Cycles." Journal of Climate 28.1 (2015): 292-305.

  4. Biannual cycles of organochlorine pesticide enantiomers in arctic air suggest changing sources and pathways

    NASA Astrophysics Data System (ADS)

    Bidleman, T. F.; Jantunen, L. M.; Hung, H.; Ma, J.; Stern, G. A.; Rosenberg, B.; Racine, J.

    2014-09-01

    Air samples collected during 1994-2000 at the Canadian arctic air monitoring station Alert (82°30' N, 62°20' W) were analyzed by enantiospecific gas chromatography - mass spectrometry for α-hexachlorocyclohexane (α-HCH), trans-chlordane (TC) and cis-chlordane (CC). Results were expressed as enantiomer fractions (EF = quantities of (+)/[(+) + (-)] enantiomers), where EFs = 0.5, <0.5 and >0.5 indicate racemic composition, and preferential depletion of (+) and (-) enantiomers, respectively. Long-term average EFs were close to racemic values for α-HCH (0.504 ± 0.004, n = 197) and CC (0.505 ± 0.004, n = 162), and deviated farther from racemic for TC (0.470 ± 0.013, n = 165). Digital filtration analysis revealed biannual cycles of lower α-HCH EFs in summer-fall and higher EFs in winter-spring. These cycles suggest volatilization of partially degraded α-HCH with EF < 0.5 from open water and advection to Alert during the warm season, and background transport of α-HCH with EF > 0.5 during the cold season. The contribution of sea-volatilized α-HCH was only 11% at Alert, vs. 32% at Resolute Bay (74.68° N, 94.90° W) in 1999. EFs of TC also followed biannual cycles of lower and higher values in the warm and cold seasons. These were in phase with low and high cycles of the TC/CC ratio (expressed as FTC = TC/(TC + CC)), which suggests greater contribution of microbially "weathered" TC in summer-fall vs. winter-spring. CC was closer to racemic than TC and displayed seasonal cycles only in 1997-1998. EF profiles are likely to change with rising contribution of secondary emission sources, weathering of residues in the environment, and loss of ice cover in the Arctic. Enantiomer-specific analysis could provide added forensic capability to air monitoring programs.

  5. Annual cycles of organochlorine pesticide enantiomers in Arctic air suggest changing sources and pathways

    NASA Astrophysics Data System (ADS)

    Bidleman, T. F.; Jantunen, L. M.; Hung, H.; Ma, J.; Stern, G. A.; Rosenberg, B.; Racine, J.

    2015-02-01

    Air samples collected during 1994-2000 at the Canadian Arctic air monitoring station Alert (82°30' N, 62°20' W) were analysed by enantiospecific gas chromatography-mass spectrometry for α-hexachlorocyclohexane (α-HCH), trans-chlordane (TC) and cis-chlordane (CC). Results were expressed as enantiomer fractions (EF = peak areas of (+)/[(+) + (-)] enantiomers), where EFs = 0.5, < 0.5 and > 0.5 indicate racemic composition, and preferential depletion of (+) and (-) enantiomers, respectively. Long-term average EFs were close to racemic values for α -HCH (0.504 ± 0.004, n = 197) and CC (0.505 ± 0.004, n = 162), and deviated farther from racemic for TC (0.470 ± 0.013, n = 165). Digital filtration analysis revealed annual cycles of lower α-HCH EFs in summer-fall and higher EFs in winter-spring. These cycles suggest volatilization of partially degraded α-HCH with EF < 0.5 from open water and advection to Alert during the warm season, and background transport of α-HCH with EF > 0.5 during the cold season. The contribution of sea-volatilized α-HCH was only 11% at Alert, vs. 32% at Resolute Bay (74.68° N, 94.90° W) in 1999. EFs of TC also followed annual cycles of lower and higher values in the warm and cold seasons. These were in phase with low and high cycles of the TC/CC ratio (expressed as FTC = TC/(TC+CC)), which suggests greater contribution of microbially "weathered" TC in summer-fall versus winter-spring. CC was closer to racemic than TC and displayed seasonal cycles only in 1997-1998. EF profiles are likely to change with rising contribution of secondary emission sources, weathering of residues in the environment, and loss of ice cover in the Arctic. Enantiomer-specific analysis could provide added forensic capability to air monitoring programs.

  6. 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

  7. The Effect of Adversary Unmanned Aerial Systems on the US Concept of Air Superiority

    DTIC Science & Technology

    2014-12-04

    release; distribution is unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT The last time an enemy aircraft attacked a member of the American...joint, and primarily offensive operations can preclude enemy attacks from the air. The United States can either change its concept of air superiority...or commit the necessary resources to ensure continued immunity from aerial attack . 15. SUBJECT TERMS Air Superiority, Remotely Piloted Aircraft

  8. Chemical Extraction of Carbon Dioxide From Air: A Strategy to Avoid Climate Change and Sustain Fossil Energy?

    NASA Astrophysics Data System (ADS)

    Dubey, M. K.; Ziock, H.; Rueff, G.; Colman, J.; Smith, W. S.

    2002-12-01

    analyzed by X ray diffraction and thermal gravimetric analysis. We identify the atmospheric sub-laminar boundary layer and the stagnant liquid surface as potential barriers to CO2 uptake. Strategies to overcome these limits are developed. We discuss other renewable, energy efficient, and effective CO2 scrubbers with lower binding energies. High-resolution simulations are also being performed to characterize the effects of atmospheric mixing, size and geometry of extractors on the collection efficiency. Capture of CO2 from air is a promising long term strategy to sustain fossil energy use by avoiding climate change but much research and development is needed to implement it. [1] Elliott S. et al.,Compensation of atmospheric CO2 buildup through engineered chemical sinkage, Geophys. Res. Lett., 28(7), 1235-1238, 2001. [2] Dubey, M. K. et al., Extraction of carbon dioxide from the atmosphere through engineered chemical sinkage, 2002 American Chemical Society, Division of Fuel Chemistry Preprints, 47(1), 81-84, 2002. [3] Johnston, et al. Chemical Transport Modeling of Potential Atmospheric Carbon Dioxide Sinks, in press Energy Conversion & Management, 2002.

  9. Note: A heated-air curtain design using the Coanda effect to protect optical access windows in high-temperature, condensing, and corrosive stack environments

    NASA Astrophysics Data System (ADS)

    Williams, Gustavious Paul; Keenan, Thomas L.; Herning, James; Kimblin, Clare; DiBenedetto, John; Anthony, Glen

    2011-01-01

    We present an air knife design for creating a heated air curtain to protect optical infrared access windows in high-temperature, condensing, and corrosive stack environments. The design uses the Coanda effect to turn the air curtain and to attach the air curtain to the window surface. The design was tested and verified on our 24 m stack and used extensively over a 6 yr period on several release stacks. During testing and subsequent use no detrimental changes to access window materials have been noted. This design allows stack monitoring without significantly affecting the stack flow profile or chemical concentration.

  10. Note: A heated-air curtain design using the Coanda effect to protect optical access windows in high-temperature, condensing, and corrosive stack environments.

    PubMed

    Williams, Gustavious Paul; Keenan, Thomas L; Herning, James; Kimblin, Clare; DiBenedetto, John; Anthony, Glen

    2011-01-01

    We present an air knife design for creating a heated air curtain to protect optical infrared access windows in high-temperature, condensing, and corrosive stack environments. The design uses the Coanda effect to turn the air curtain and to attach the air curtain to the window surface. The design was tested and verified on our 24 m stack and used extensively over a 6 yr period on several release stacks. During testing and subsequent use no detrimental changes to access window materials have been noted. This design allows stack monitoring without significantly affecting the stack flow profile or chemical concentration.

  11. Effects of air-polishing powders on color stability of composite resins

    PubMed Central

    GÜLER, Ahmet Umut; DURAN, Ibrahim; YÜCEL, Ali Çagin; ÖZKAN, Pelin

    2011-01-01

    Objectives The purpose of this study was to investigate the effect of different air-polishing powders on the color stability of different types of composite resin restorative materials. Material and methods Thirty cylindrical specimens (15×2 mm) were prepared for each of 7 composite resin restorative materials. All specimens were polished with a series of aluminum oxide polishing discs (Sof-Lex). The prepared specimens of each composite resin were randomly divided into 3 groups of 10 specimens each, for control (Group-C) and two air-powder applications (Group-CP: Cavitron Prophy-Jet; Group-PS: Sirona ProSmile prophylaxis powder). A standard air-polishing unit (ProSmile Handly) was used. All specimens were air-powdered for 10 s at 4-bar pressure. The distance of the spray nosel from the specimens was approximately 10 mm and angulation of the nosel was 90º. Specimens were stored in 100 mL of coffee (Nescafe Classic) for 24 h at 37ºC. Color measurement of all specimens was recorded before and after exposure to staining agent with a colorimeter (Minolta CR-300). Color differences (∆E*) between the 2 color measurements (baseline and after 24 h storage) were calculated. The data were analyzed with a 2-way ANOVA test, and mean values were compared by the Tukey HSD test (p≤0.05). Results According to the 2-way ANOVA results, composite resin restorative materials, air-polishing powders, and their interaction were statistically significant (p<0.05) For Aelite Aesthetic Enemal, Filtek Z250, Grandio, CeramX Mono, and Quixfil composite resin restorative materials, no significant difference was observed between Group-PS and Group-CP (p>.05) and these groups demonstrated the highest ∆E* values. For Filtek Silorane and IntenS, the highest ∆E* values were observed in Group-PS. The lowest ∆E* values for all composite resin groups were observed in Group-C. When comparing the 7 composite resin restorative materials, Aelite Aesthetic Enemal demonstrated significantly less

  12. Cytologic respiratory changes in workers exposed to air pollution and cigarette smoking

    SciTech Connect

    Vetrani, A.; Palombini, L.; Del Basso De Caro, M.L.; Marino, M.

    1981-01-01

    Sputum specimens taken at random from 420 of 2,500 sweepers of Naples (369 male smokers, at least ten filter cigarettes daily for a minimum of ten years, and 51 male controls, nonsmokers) have been investigated. In the smokers group, 220 cases (59.6%) with nonspecific chronic inflammatory disease, 54 cases (14.6%) with regular squamous metaplasia, 13 (3.5%) with atypical squamous metaplasia, and one case (0.3%) of presumed carcinoma in situ have been identified. In the control group, 17 cases (35.3%) of nonspecific chronic inflammatory processes with occasional regular squamous metaplasia were the only found pathology. Based upon their results, the authors have been unable to demonstrate that air pollution may enhance the smoking effect on the respiratory tract.

  13. Effects of air pollution on general practitioner consultations for upper respiratory diseases in London

    PubMed Central

    Hajat, S; Anderson, H; Atkinson, R; Haines, A; Seaton, A.

    2002-01-01

    Objectives: Few published studies have examined the effect of air pollution on upper respiratory conditions. Furthermore, most epidemiological studies on air pollution focus on mortality or hospital admissions as the main health outcomes, but very rarely consider the effect in primary care. If pollution effects do exist then the public health impact could be considerable because of the many patient contacts involved. We investigated the relation between air pollution and upper respiratory disease as reflected in number of consultations made at family practices in London. Methods: The study used non-parametric methods of analysis of time series data, adjusting for seasonal factors, day of the week, holiday effects, influenza, weather, pollen concentrations, and serial correlation. Results: It was estimated that a 10–90th percentile change (13–31 µg/m3) in sulphur dioxide (SO2) measures resulted in a small increase in numbers of childhood consultation: 3.5% (95% confidence interval (95% CI 1.4% to 5.8%). Stronger associations were found in the case of a 10–90th percentile change (16–47 µg/m3) in fine particles (PM10) in adults aged 15–64 5.7% (2.9% to 8.6%), and in adults aged 65 and over: 10.2% (5.3% to 15.3%). In general, associations were strongest in elderly people, weakest in the children, and were largely found in the winter months for these two age groups, and in the summer months for adults aged 15–64. An apparent decrease in consultations was associated with ozone concentrations but this was most pronounced in colder months when ozone concentrations were at their lowest. Conclusions: The results suggest an adverse effect of air pollution on consultations for upper respiratory symptoms, in particular in the case of PM10 and SO2. The effects are relatively small; however, due to the many consultations made in primary care, the impact on demand for services could be considerable. PMID:11983844

  14. The biotic effects of climate change.

    PubMed

    Lister, Adrian M

    2009-02-01

    Humans are part of the biosphere and dependent upon it. The impact of climate change on 'ecosystem services' is therefore of extreme concern. Many studies demonstrate unequivocally that global warming is shifting the distribution of animal and plant species, affecting the composition not only of natural ecosystems but of agricultural ones as well, and also altering the range and impact of pathogenic organisms. The future trajectory of such complex processes is hard to map accurately, but even conservative estimates predict substantial species extinctions and changes in regional productivity. There is still a chance to significantly mitigate these effects, however, if urgent measures are taken. The biotic effects of climate change are strongly exacerbated by ongoing habitat destruction, which no less urgently needs to be halted or reversed by concerted international action. In terms of its rate and its human causation, the present crisis is not analogous to past 'natural' events.

  15. The Impact of Climate Change on Air Quality and Respiratory Disease: Maryland/DC Metropolitan Area

    NASA Astrophysics Data System (ADS)

    Kaushiva, A.; Strong, S. B.; Babin, S. M.; Paxton, L. J.

    2011-12-01

    Ground level ozone, or tropospheric ozone, forms smog and becomes directly harmful to humans by exacerbating respiratory conditions, primarily asthma (Knowlton et al. 2004). As climate change progresses, increased ozone concentrations emerge as a major public health concern (Gardiner et al. 2011). Increasing ground level ozone concentrations have been directly correlated with rising temperatures (Patz et al. 2005). The projected increase in ozone concentration caused by climate induced temperature change is 1-2 ppb in 2020 and 2-7 ppb in 2050, with associated temperature increases of 1-2 degrees Fahrenheit and 2-5.5 degrees Fahrenheit, respectively (UCS, 2011). Those with existing respiratory conditions, children and the elderly, and those who spend a significant amount of time outdoors are the most sensitive to ground level ozone pollution (Schlink et al. 2006). In Maryland, there would be approximately 68,894 occurrences of acute respiratory symptoms associated with a 2 ppb climate penalty in 2020, and the total costs for health impacts associated with this would be approximately $133,398,027 (UCS, 2011). In their 2011 "State of the Air" report, the American Lung Association rated the Washington/Baltimore/Northern Virginia region as one of the 25 most ozone polluted regions nationwide (ALA, 2011). We examine asthma hospital admissions data for the Maryland/DC metropolitan region between 2005 and 2010 and identify possible correlations with the reported ozone measurements provided by the EPA (CASTNET). We examine trends between the archived temperatures from NCEP reanalysis data, the EPA ozone data, and reported asthma cases. We utilize these trends to investigate the future impact of changes in ozone concentration based on the IPCC AR4 and SRES emissions scenarios and attempt to quantify the financial burden of its implications. Visualizations from this data can serve as important educational and planning tools for decision makers in the Maryland, DC, and

  16. Overview of different aspects of climate change effects on soils

    SciTech Connect

    Qafoku, Nikolla P.

    2014-08-01

    Climate change [i.e., high atmospheric carbon dioxide (CO2) concentrations (≥400 ppm); increasing air temperatures (2-4°C or greater); significant and/or abrupt changes in daily, seasonal, and inter-annual temperature; changes in the wet/dry cycles; intensive rainfall and/or heavy storms; extended periods of drought; extreme frost; heat waves and increased fire frequency] is and will significantly affect soil properties and fertility, water resources, food quantity and quality, and environmental quality. Biotic processes that consume atmospheric CO2 and create organic carbon (C) that is either reprocessed to CO2 or stored in soils, are the subject of active current investigations with great concern over the influence of climate change. In addition, abiotic C cycling and its influence on the inorganic C pool in soils is a fundamental global process in which acidic atmospheric CO2 participates in the weathering of carbonate and silicate minerals, ultimately delivering bicarbonate and Ca2+ or other cations that precipitate in the form of carbonates in soils or are transported to the rivers, lakes, and oceans. Soil responses to climate change will be complex, and there are many uncertainties and unresolved issues. The objective of the review is to initiate and further stimulate a discussion about some important and challenging aspects of climate-change effects on soils, such as accelerated weathering of soil minerals and resulting C and elemental fluxes in and out of soils, soil/geo-engineering methods used to increase C sequestration in soils, soil organic matter (SOM) protection, transformation and mineralization, and SOM temperature sensitivity. This review reports recent discoveries and identifies key research needs required to understand the effects of climate change on soils.

  17. GLOBAL CHANGE EFFECTS ON CORAL REEF CONDITION

    EPA Science Inventory

    Fisher, W., W. Davis, J. Campbell, L. Courtney, P. Harris, B. Hemmer, M. Parsons, B. Quarles and D. Santavy. In press. Global Change Effects on Coral Reef Condition (Abstract). To be presented at the EPA Science Forum: Healthy Communities and Ecosystems, 1-3 June 2004, Washington...

  18. Managing Chemotherapy Side Effects: Nerve Changes

    MedlinePlus

    ... ational C ancer I nstitute Managing Chemotherapy Side Effects Nerve Changes “My fingers and toes felt numb and tingly. It was hard to button shirts. I got help from my wife. To keep from getting cuts, I always wore shoes.” u.s. Department of health anD human services national ...

  19. Air pollutin and acid rain, Report 4. Effects of air pollution and acid rain on fish, wildlife, and their habitats - lakes

    SciTech Connect

    Potter, W.; Adler, D.

    1982-06-01

    This report summarizes the results of scientific research related to air pollution effects on fish and wildlife associated with lakes and wetlands. The effects of photochemical oxidants, particulates, and acidifying air pollutants on water quality and lake and wetland biota are summarized. The characteristics that indicate lake sensitivity to air pollutants, in particular acidifying pollutants, are presented. Socioeconomic aspects of air pollution impacts on lake ecosystems are discussed and areas of research are suggested to increase the understanding of the effects of air pollutants on lake and wetland ecosystems. 172 references, 1 figure, 6 tables.

  20. 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.

  1. Air Pollution in Megacities: Sources and Regional/Global Effects

    NASA Astrophysics Data System (ADS)

    Artaxo, P.

    2007-12-01

    Air Pollution in Megacities is increasing significantly in all continents. The socio-economic and health problems are escalating, especially in developing countries. In terms of sources, urban transportation is relevant in most cities, as well as industrial pollution. In Latin American Cities such as Sao Paulo, Mexico City and Santiago, serious governmental efforts are being doing to reduce emissions and effects. Latin America has about 300 cities with population above 300.000 people. In Sao Paulo, the significant increase in the use of ethanol as fuel brings important increase in aldehyde concentrations. In all 3 Megacities, high aerosol concentrations are observed, with clear effects on population health. Large studies on aerosol source apportionment were done in these 3 cities, and detailed results will be presented. Quantification of aerosol sources is a problem, especially in the organic aerosol component that is high in most of Megacities. In Asia and Africa, the problems are similar as in Latin America, and the large emissions from these urban centers are relevant and needs to be taken into account in policies to reduce carbon dioxide emissions.

  2. Climate change effect on outdoor ambiences in Iranian cities.

    PubMed

    Orosa, José Antonio; Roshan, Gholamreza; Negahban, Saeed

    2014-03-01

    In present research work the effect of climate change over the humidex in Iran is analyzed. From this research, we can conclude that the PDIAQ index showed a special sensibility to changes in temperature and relative humidity, hence, it can be an interesting tool, may be even better than the humidex to show the expected effect of climate change in perception of air quality. Thus, it was found that the humidex expected in the future will be more elevated than that in the preceding period and, on the other hand, the PDWRC has clearly reached a lower value than in the preceding period. The same effects, other than those using the earlier indexes in a more detailed manner, were observed with the PDIAQ. This index showed a higher sensitivity to variations in temperature and relative humidity, than the humidex. Finally, the main results obtained must be considered at the time of design and during construction of future buildings, since buildings that are being constructed today will be occupied in the future years of the 2100s.

  3. Responses of soil respiration to elevated CO2, air warming, and changing soil water availability in an old-field grassland<