Science.gov

Sample records for greenhouse gases releases

  1. Greenhouse Gases

    MedlinePlus

    ... Greenhouse Gases Come From Outlook for Future Emissions Recycling and Energy Nonrenewable Sources Oil and Petroleum Products ... Power Wave Power Ocean Thermal Energy Conversion Biomass Wood and Wood Waste Waste-to-Energy (MSW) Landfill ...

  2. GREENHOUSE GASES AND AGRICULTURE

    EPA Science Inventory

    Agriculture ranks third in its contribution to Earth's anthropogenically nhanced greenhouse effect. Energy use and production and chlorofluorocarbons are anked first and second, respectively.) pecifically, greenhouse gas sources and inks are increased, and sinks are decreased, by...

  3. Climate Change and Greenhouse Gases

    NASA Technical Reports Server (NTRS)

    Ledley, Tamara S.; Sundquist, Eric; Schwartz, Stephen; Hall, Dorothy K.; Fellows, Jack; Killeen, Timothy

    1999-01-01

    The American Geophysical Union (AGU), as a scientific organization devoted to research on the Earth and space sciences, provides current scientific information to the public on issues pertinent to geophysics. The Council of the AGU approved a position statement on Climate Change and Greenhouse Gases in December 1998. The statement, together with a short summary of the procedures that were followed in its preparation, review, and adoption were published in the February 2, 1999 issue of Eos ([AGU, 1999]. The present article reviews scientific understanding of this issue as presented in peer-reviewed publications that serves as the underlying basis of the position statement.

  4. Greenhouse gases: What is their role in climate change

    SciTech Connect

    Edmonds, J.A.; Chandler, W.U. ); Wuebbles, D. )

    1990-12-01

    This paper summarizes information relevant to understanding the role of greenhouse gases in the atmosphere. It examines the nature of the greenhouse effect, the Earth's radiation budget, the concentrations of these gases in the atmosphere, how these concentrations have been changing, natural processes which regulate these concentrations of greenhouse gases, residence times of these gases in the atmosphere, and the rate of release of gases affecting atmospheric composition by human activities. We address the issue of the greenhouse effect itself in the first section. In the second section we examine trends in atmospheric concentration of greenhouse gases and emissions sources. In the third section, we examine the natural carbon cycle and its role in determining the atmospheric residence time of carbon dioxide (CO{sub 2}). In the fourth section, we examine the role atmospheric chemistry plays in the determining the concentrations of greenhouse gases. This paper is not intended to be an exhaustive treatment of these issues. Exhaustive treatments can be found in other volumes, many of which are cited throughout this paper. Rather, this paper is intended to summarize some of the major findings, unknowns, and uncertainties associated with the current state of knowledge regarding the role of greenhouse gases in the atmosphere. 57 refs., 11 figs., 11 tabs.

  5. Greenhouse Trace Gases in Deadwood

    NASA Astrophysics Data System (ADS)

    Covey, Kristofer; Bueno de Mesquita, Cliff; Oberle, Brad; Maynard, Dan; Bettigole, Charles; Crowther, Thomas; Duguid, Marlyse; Steven, Blaire; Zanne, Amy; Lapin, Marc; Ashton, Mark; Oliver, Chad; Lee, Xuhui; Bradford, Mark

    2016-04-01

    Deadwood, long recognized as playing an important role in carbon cycling in forest ecosystems, is more recently drawing attention for its potential role in the cycling of other greenhouse trace gases. We report data from four independent studies measuring internal gas concentrations in deadwood in in three Quercus dominated upland forest systems in the Northeastern and Central United States. Mean methane concentrations in deadwood were 23 times atmospheric levels, indicating a lower bound, mean radial wood surface area flux of ~6 x 10-4 μmol CH4 m-2 s-1. Site, decay class, diameter, and species were all highly significant predictors of methane abundance in deadwood, and log diameter and decay stage interacted as important controls limiting methane concentrations in the smallest and most decayed logs. Nitrous oxide concentrations were negatively correlated with methane and on average ~25% lower than ambient, indicating net consumption of nitrous oxide. These data suggest nonstructural carbohydrates fuel archaeal methanogens and confirm the potential for widespread in situ methanogenesis in both living and deadwood. Applying this understanding to estimate methane emissions from microbial activity in living trees implies a potential global flux of 65.6±12.0 Tg CH4 yr-1, more than 20 times greater than currently considered.

  6. Synthetic greenhouse gases to decline if Montreal Protocol amended

    NASA Astrophysics Data System (ADS)

    Wendel, JoAnna

    2014-07-01

    The Montreal Protocol, an international treaty designed to reduce the release into the atmosphere of ozone-depleting gases such as hydrochlorofluorocarbons and chlorofluorocarbons, has been successful since its implementation in the late 1980s. However, related greenhouse gases, such as hydrofluorocarbons (HFCs), have increased in concentration in the atmosphere since then. HFCs, along with other synthetic greenhouse gases (SGHGs), account for a radiative forcing almost 20% as large as that due to the increase in carbon dioxide (CO2) since the preindustrial era.

  7. Voluntary reporting of greenhouse gases, 1995

    SciTech Connect

    1996-07-01

    The Voluntary Reporting Program for greenhouse gases is part of an attempt by the U.S. Government to develop innovative, low-cost, and nonregulatory approaches to limit emissions of greenhouse gases. It is one element in an array of such programs introduced in recent years as part of the effort being made by the United States to comply with its national commitment to stabilize emissions of greenhouse gases under the Framework Convention on Climate Change. The Voluntary Reporting Program, developed pursuant to Section 1605(b) of the Energy Policy Act of 1992, permits corporations, government agencies, households, and voluntary organizations to report to the Energy Information Administration (EIA) on actions taken that have reduced or avoided emissions of greenhouse gases.

  8. Where do California's greenhouse gases come from?

    ScienceCinema

    Fischer, Marc

    2013-05-29

    Last March, more than two years after California passed legislation to slash greenhouse gas emissions 25 percent by 2020, Lawrence Berkeley National Laboratory scientist Marc Fischer boarded a Cessna loaded with air monitoring equipment and crisscrossed the skies above Sacramento and the Bay Area. Instruments aboard the aircraft measured a cocktail of greenhouse gases: carbon dioxide from fossil fuel use, methane from livestock and landfills, CO2 from refineries and power plants, traces of nitrous oxide from agriculture and fuel use, and industrially produced other gases like refrigerants. The flight was part of the Airborne Greenhouse Gas Emissions Survey, a collaboration between Berkeley Lab, the National Oceanic and Atmospheric Administration, and the University of California, and UC Davis to pinpoint the sources of greenhouse gases in central California. The survey is intended to improve inventories of the states greenhouse gas emissions, which in turn will help scientists verify the emission reductions mandated by AB-32, the legislation enacted by California in 2006.

  9. Where do California's greenhouse gases come from?

    SciTech Connect

    Fischer, Marc

    2009-01-01

    Last March, more than two years after California passed legislation to slash greenhouse gas emissions 25 percent by 2020, Lawrence Berkeley National Laboratory scientist Marc Fischer boarded a Cessna loaded with air monitoring equipment and crisscrossed the skies above Sacramento and the Bay Area. Instruments aboard the aircraft measured a cocktail of greenhouse gases: carbon dioxide from fossil fuel use, methane from livestock and landfills, CO2 from refineries and power plants, traces of nitrous oxide from agriculture and fuel use, and industrially produced other gases like refrigerants. The flight was part of the Airborne Greenhouse Gas Emissions Survey, a collaboration between Berkeley Lab, the National Oceanic and Atmospheric Administration, and the University of California, and UC Davis to pinpoint the sources of greenhouse gases in central California. The survey is intended to improve inventories of the states greenhouse gas emissions, which in turn will help scientists verify the emission reductions mandated by AB-32, the legislation enacted by California in 2006.

  10. Atmospheric Chemistry and Greenhouse Gases

    SciTech Connect

    Ehhalt, D.; Prather, M.; Dentener, F.; Derwent, R.; Dlugokencky, Edward J.; Holland, E.; Isaksen, I.; Katima, J.; Kirchhoff, V.; Matson, P.; Midgley, P.; Wang, M.; Berntsen, T.; Bey, I.; Brasseur, G.; Buja, L.; Collins, W. J.; Daniel, J. S.; DeMore, W. B.; Derek, N.; Dickerson, R.; Etheridge, D.; Feichter, J.; Fraser, P.; Friedl, R.; Fuglestvedt, J.; Gauss, M.; Grenfell, L.; Grubler, Arnulf; Harris, N.; Hauglustaine, D.; Horowitz, L.; Jackman, C.; Jacob, D.; Jaegle, L.; Jain, Atul K.; Kanakidou, M.; Karlsdottir, S.; Ko, M.; Kurylo, M.; Lawrence, M.; Logan, J. A.; Manning, M.; Mauzerall, D.; McConnell, J.; Mickley, L. J.; Montzka, S.; Muller, J. F.; Olivier, J.; Pickering, K.; Pitari, G.; Roelofs, G.-J.; Rogers, H.; Rognerud, B.; Smith, Steven J.; Solomon, S.; Staehelin, J.; Steele, P.; Stevenson, D. S.; Sundet, J.; Thompson, A.; van Weele, M.; von Kuhlmann, R.; Wang, Y.; Weisenstein, D. K.; Wigley, T. M.; Wild, O.; Wuebbles, D.J.; Yantosca, R.; Joos, Fortunat; McFarland, M.

    2001-10-01

    Chapter 4 of the IPCC Third Assessment Report Climate Change 2001: The Scientific Basis. Sections include: Executive Summary 2414.1 Introduction 2434.2 Trace Gases: Current Observations, Trends and Budgets 2484.3 Projections of Future Emissions 2664.4 Projections of Atmospheric Composition for the 21st Century 2674.5 Open Questions 2774.6 Overall Impact of Global Atmospheric Chemistry Change 279

  11. Managing biogeochemical cycles to reduce greenhouse gases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This special issue focuses on terrestrial biogeochemical cycles and their roles in determining current continental-scale budgets and future trends in biogenic greenhouse gases (GHGs) for North America. Understanding the current magnitude and forecasting future trajectories of atmospheric GHG concent...

  12. Managing biogeochemical cycles to reduce greenhouse gases

    SciTech Connect

    Post, Wilfred M; Venterea, Rodney

    2012-01-01

    This special issue focuses on terrestrial biogeochemical cycles as they relate to North America-wide budgeting and future projection of biogenic greenhouse gases (GHGs). Understanding the current magnitude and providing guidance on the future trajectories of atmospheric concentrations of these gases requires investigation of their (i) biogeochemical origins, (ii) response to climate feedbacks and other environmental factors, and (iii) susceptibility to management practices. This special issue provides a group of articles that present the current state of continental scale sources and sinks of biogenic GHGs and the potential to better manage them in the future.

  13. Voluntary reporting of greenhouse gases 1997

    SciTech Connect

    1999-05-01

    The Voluntary Reporting of Greenhouse Gases Program, required by Section 1605(b) of the Energy Policy Act of 1992, records the results of voluntary measures to reduce, avoid, or sequester greenhouse gas emissions. In 1998, 156 US companies and other organizations reported to the Energy information Administration that, during 1997, they had achieved greenhouse gas emission reductions and carbon sequestration equivalent to 166 million tons of carbon dioxide, or about 2.5% of total US emissions for the year. For the 1,229 emission reduction projects reported, reductions usually were measured by comparing an estimate of actual emissions with an estimate of what emissions would have been had the project not been implemented.

  14. 40 CFR 70.12 - Enforceable commitments for further actions addressing greenhouse gases (GHGs).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... actions addressing greenhouse gases (GHGs). 70.12 Section 70.12 Protection of Environment ENVIRONMENTAL... commitments for further actions addressing greenhouse gases (GHGs). (a) Definitions. (1) Greenhouse Gases... six greenhouse gases: carbon dioxide, nitrous oxide, methane, hydrofluorocarbons,...

  15. 40 CFR 70.12 - Enforceable commitments for further actions addressing greenhouse gases (GHGs).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... actions addressing greenhouse gases (GHGs). 70.12 Section 70.12 Protection of Environment ENVIRONMENTAL... commitments for further actions addressing greenhouse gases (GHGs). (a) Definitions. (1) Greenhouse Gases... six greenhouse gases: carbon dioxide, nitrous oxide, methane, hydrofluorocarbons,...

  16. 40 CFR 70.12 - Enforceable commitments for further actions addressing greenhouse gases (GHGs).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... actions addressing greenhouse gases (GHGs). 70.12 Section 70.12 Protection of Environment ENVIRONMENTAL... commitments for further actions addressing greenhouse gases (GHGs). (a) Definitions. (1) Greenhouse Gases... six greenhouse gases: carbon dioxide, nitrous oxide, methane, hydrofluorocarbons,...

  17. 40 CFR 70.12 - Enforceable commitments for further actions addressing greenhouse gases (GHGs).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... actions addressing greenhouse gases (GHGs). 70.12 Section 70.12 Protection of Environment ENVIRONMENTAL... commitments for further actions addressing greenhouse gases (GHGs). (a) Definitions. (1) Greenhouse Gases... six greenhouse gases: carbon dioxide, nitrous oxide, methane, hydrofluorocarbons,...

  18. Effect of Greenhouse Gases Dissolved in Seawater.

    PubMed

    Matsunaga, Shigeki

    2016-01-01

    A molecular dynamics simulation has been performed on the greenhouse gases carbon dioxide and methane dissolved in a sodium chloride aqueous solution, as a simple model of seawater. A carbon dioxide molecule is also treated as a hydrogen carbonate ion. The structure, coordination number, diffusion coefficient, shear viscosity, specific heat, and thermal conductivity of the solutions have been discussed. The anomalous behaviors of these properties, especially the negative pressure dependence of thermal conductivity, have been observed in the higher-pressure region. PMID:26729101

  19. Effect of Greenhouse Gases Dissolved in Seawater

    PubMed Central

    Matsunaga, Shigeki

    2015-01-01

    A molecular dynamics simulation has been performed on the greenhouse gases carbon dioxide and methane dissolved in a sodium chloride aqueous solution, as a simple model of seawater. A carbon dioxide molecule is also treated as a hydrogen carbonate ion. The structure, coordination number, diffusion coefficient, shear viscosity, specific heat, and thermal conductivity of the solutions have been discussed. The anomalous behaviors of these properties, especially the negative pressure dependence of thermal conductivity, have been observed in the higher-pressure region. PMID:26729101

  20. Veracruz State Preliminary Greenhouse Gases Emissions Inventory

    NASA Astrophysics Data System (ADS)

    Welsh Rodriguez, C.; Rodriquez Viqueira, L.; Guzman Rojas, S.

    2007-05-01

    At recent years, the international organisms such as United Nations, has discussed that the temperature has increased slightly and the pattern of precipitations has changed in different parts of the world, which cause either extreme droughts or floods and that the extreme events have increased. These are some of the risks of global climate change because of the increase of gas concentration in the atmosphere such as carbon dioxides, nitrogen oxides and methane - which increase the greenhouse effect. Facing the consequences that could emerge because of the global temperature grown, there is a genuine necessity in different sectors of reduction the greenhouse gases and reduced the adverse impacts of climate change. To solve that, many worldwide conventions have been realized (Rio de Janeiro, Kyoto, Montreal) where different countries have established political compromises to stabilize their emissions of greenhouse gases. The mitigation and adaptation policies merge as a response to the effects that the global climate change could have, on the humans as well as the environment. That is the reason to provide the analysis of the areas and geographic zones of the country that present major vulnerability to the climate change. The development of an inventory of emissions that identifies and quantifies the principal sources of greenhouse gases of a country, and also of a region is basic to any study about climate change, also to develop specific political programs that allow to preserve and even improve a quality of the atmospheric environment, and maybe to incorporate to international mechanisms such as the emissions market. To estimate emissions in a systematic and consistent way on a regional, national and international level is a requirement to evaluate the feasibility and the cost-benefit of instrumented possible mitigation strategies and to adopt politics and technologies to reduce emissions. Mexico has two national inventories of emissions, 1990 and 1995, now it is

  1. A Simple Experiment to Demonstrate the Effects of Greenhouse Gases

    ERIC Educational Resources Information Center

    Keating, C. F.

    2007-01-01

    The role of greenhouse gases in our atmosphere is the subject of considerable discussion and debate. Global warming is well-documented, as is the continually increasing amount of greenhouse gases that human activity puts in the air. Is there a relationship between the two? The simple experiment described in this paper provides a good demonstration…

  2. World Energy Projection System Plus Model Documentation: Greenhouse Gases Model

    EIA Publications

    2011-01-01

    This report documents the objectives, analytical approach and development of the World Energy Projection System Plus (WEPS ) Greenhouse Gases Model. It also catalogues and describes critical assumptions, computational methodology, parameter estimation techniques, and model source code.

  3. Trace Gases, CO2, Climate, and the Greenhouse Effect.

    ERIC Educational Resources Information Center

    Aubrecht, Gordon J., II

    1988-01-01

    Reports carbon dioxide and other trace gases can be the cause of the Greenhouse Effect. Discusses some effects of the temperature change and suggests some solutions. Included are several diagrams, graphs, and a table. (YP)

  4. 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

  5. GLOBAL MITIGATION OF NON-CO2 GREENHOUSE GASES

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mitigation of noncarbon dioxide (non-CO2) greenhouse gas emissions can be a relatively inexpensive supplement to CO2-only mitigation strategies. The non-CO2 gases include methane (CH4), nitrous oxide (N2O), and a number of high global warming potential (high- GWP) or fluorinated gases. These ga...

  6. Are recent Arctic ozone losses caused by increasing greenhouse gases?

    NASA Astrophysics Data System (ADS)

    Rieder, Harald E.; Polvani, Lorenzo M.

    2013-08-01

    has been suggested that the Arctic ozone losses observed in recent years might be a manifestation of climate change due to increasing greenhouse gases. We here offer evidence to the contrary, by focusing on the volume of polar stratospheric clouds (VPSC), a convenient proxy for polar ozone loss whose simplicity allows for easily reproducible results. First, we analyze the time series of VPSC in three reanalysis data sets and find no statistically significant trends in VPSC-nor changes in their probability density functions-over the period 1979-2011. Second, we analyze VPSC in a stratosphere-resolving chemistry-climate model forced uniquely with increasing greenhouse gases following the A1B scenario: here too, we find no significant changes in VPSC over the entire 21st century. Taken together, these results strongly suggest that the sporadic high ozone losses in recent years have not been caused by increasing greenhouse gases.

  7. Are recent Arctic ozone losses caused by increasing greenhouse gases?

    NASA Astrophysics Data System (ADS)

    Rieder, H.; Polvani, L. M.

    2013-12-01

    It has been suggested that the Arctic ozone losses observed in recent years might be a manifestation of climate change due to increasing greenhouse gases. We here offer evidence to the contrary, by focusing on the volume of polar stratospheric clouds (VPSC), a convenient proxy for polar ozone loss whose simplicity allows for easily reproducible results. First, we analyze the time series of VPSC in three reanalysis datasets and find no statistically significant trends in VPSC - nor changes in their probability density functions - over the period 1979-2011. Second, we analyze VPSC in a stratosphere-resolving chemistry-climate model forced uniquely with increasing greenhouse gases following the A1B scenario: here too, we find no significant changes in VPSC over the entire 21st century. Taken together, these results strongly suggest that the sporadic high ozone losses in recent years have not been caused by increasing greenhouse gases.

  8. Emissions of greenhouse gases in the United States 1997

    SciTech Connect

    1998-10-01

    This is the sixth annual report on aggregate US national emissions of greenhouse gases. It covers emissions over the period 1990--1996, with preliminary estimates of emissions for 1997. Chapter one summarizes some background information about global climate change and the greenhouse effect. Important recent developments in global climate change activities are discussed, especially the third Conference of the Parties to the Framework Convention on Climate Change, which was held in December of 1997 in Kyoto, Japan. Chapters two through five cover emissions of carbon dioxide, methane, nitrous oxide, halocarbons and related gases, respectively. Chapter six describes potential sequestration and emissions of greenhouse gases as a result of land use changes. Six appendices are included in the report. 96 refs., 38 tabs.

  9. Greenhouse effect of chlorofluorocarbons and other trace gases

    NASA Technical Reports Server (NTRS)

    Hansen, James; Lacis, Andrew; Prather, Michael

    1989-01-01

    A comparison is made of the radiative (greenhouse) forcing of the climate system due to changes of atmospheric chlorofluorocarbons and other trace gases. It is found that CFCs, defined to include chlorofluorocarbons, chlorocarbons, and fluorocarbons, now provide about one-quater of current annual increases in anthropogenic greenhouse climate forcing. If the growth rates of CFC production in the early 1970s had continued to the present, current annual growth of climate forcing due to CFCs would exceed that due to CO2.

  10. Impact of greenhouse gases on the Earth's ozone layer

    NASA Astrophysics Data System (ADS)

    Zadorozhny, Alexander

    A numerical 2-D zonally averaged interactive dynamical radiative-photochemical model of the ozonosphere including aerosol physics is used to examine the role of the greenhouse gases CO2 , CH4 , and N2 O in the future long-term changes of the Earth's ozone layer, in particular in its recovery after reduction of anthropogenic discharges of chlorine and bromine compounds into the atmosphere. The model allows calculating self-consistently diabatic circulation, temperature, gaseous composition of the troposphere and stratosphere at latitudes from the South to North Poles, as well as distribution of sulphate aerosol particles and polar stratospheric clouds (PSCs) of types I and II. The scenarios of expected changes of the anthropogenic pollutants for the period from 1980 through 2050 are taken from Climate Change 2001. The processes, which determine the influence of anthropogenic growth of atmospheric abundance of the greenhouse gases on the dynamics of recovery of the Earth's ozone layer, have been studied in details. Expected cooling of the stratosphere caused by increases of greenhouse gases, most importantly CO2 , essentially influences the ozone layer by two ways: through temperature dependencies of the gas phase reaction rates and through enhancement of polar ozone depletion via increased PSC formation. The model calculations show that a weakness in efficiencies of all gas phase catalytic cycles of the ozone destruction due to cooling of the stratosphere is a dominant mechanism of the impact of the greenhouse gases on the ozone layer in Antarctic as well as at the lower latitudes. This mechanism leads to a significant acceleration of the ozone layer recovery here because of the greenhouse gases growth. On the contrary, the mechanism of the impact of the greenhouse gases on the ozone through PSC modification begins to be more effective in Arctic in comparison with the gas phase mechanism in springs after about 2020, which leads to retard the expected recovery of the

  11. Welcome to Greenhouse Gases: Science and Technology: Editorial

    SciTech Connect

    Oldenburg, C.M.; Maroto-Valer, M.M.

    2011-02-01

    This editorial introduces readers and contributors to a new online journal. Through the publication of articles ranging from peer-reviewed research papers and short communications, to editorials and interviews on greenhouse gas emissions science and technology, this journal will disseminate research results and information that address the global crisis of anthropogenic climate change. The scope of the journal includes the full spectrum of research areas from capture and separation of greenhouse gases from flue gases and ambient air, to beneficial utilization, and to sequestration in deep geologic formations and terrestrial (plant and soil) systems, as well as policy and technoeconomic analyses of these approaches.

  12. Production of Greenhouse Gases in The Atmosphere of Early Mars

    NASA Technical Reports Server (NTRS)

    Kress, Monika E.; McKay, Christopher P.; DeVincenzi, Donald L. (Technical Monitor)

    2000-01-01

    Mars was much warmer and wetter 3.5 to 4 billion years ago than it is today, suggesting that its climate was able to support life in the distant past. Carbon dioxide and methane are greenhouse gases which may have kept Mars warm during this time. We explore the possibility that these gases were produced via grain-catalyzed reactions in the warm, dusty aftermath of large comet and/or asteroid impacts which delivered Mars, volatile inventory.

  13. Biomass Burning and the Production of Greenhouse Gases. Chapter 9

    NASA Technical Reports Server (NTRS)

    Levine, Joel S.

    1994-01-01

    Biomass burning is a source of greenhouse gases, carbon dioxide, methane, and nitrous oxide. In addition, biomass burning is a source of chemically active gases, including carbon monoxide, nonmethane hydrocarbons, and nitric oxide. These gases, along with methane, lead to the chemical production of tropospheric ozone (another greenhouse gas) as well as control the concentration of the hydroxyl radical, which regulates the lifetime of almost every atmospheric gas. Following biomass burning, biogenic emissions of nitrous oxide, nitric oxide, and methane are significantly enhanced. It is hypothesized that enhanced postburn biogenic emissions of these gases are related to fire-induced changes in soil chemistry and/or microbial ecology. Biomass burning, once believed to be a tropical phenomenon, has been demonstrated by satellite imagery to also be a regular feature of the world's boreal forests. One example of biomass burning is the extensive 1987 fire that destroyed more than 12 million acres of boreal forest in the People's Republic of China and across its border in the Soviet Union. Recent estimates indicate that almost all biomass burning is human-initiated and that it is increasing with time. With the formation of greenhouse and chemically active gases as direct combustion products and a longer-term enhancement of biogenic emissions of gases, biomass burning may be a significant driver for global change.

  14. OPTIONS FOR ABATING GREENHOUSE GASES FROM EXHAUST STREAMS.

    SciTech Connect

    FTHENAKIS,V.

    2001-12-01

    This report examines different alternatives for replacing, treating, and recycling greenhouse gases. It is concluded that treatment (abatement) is the only viable short-term option. Three options for abatement that were tested for use in semiconductor facilities are reviewed, and their performance and costs compared. This study shows that effective abatement options are available to the photovoltaic (PV) industry, at reasonable cost.

  15. Iatrogenic greenhouse gases: the role of anaesthetic agents.

    PubMed

    Uzoigwe, Chika E; Sanchez Franco, Luis C; Forrest, Michael D

    2016-01-01

    The contribution of health-care activity to climate change is not negligible and is increasing. Anaesthetic greenhouse gases, in particular the fluranes, have a much more potent global warming capacity, volume for volume, than carbon dioxide, but their emissions remain completely unregulated. PMID:26903451

  16. The Global Research Alliance on agricultural greenhouse gases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Global Research Alliance on Agricultural Greenhouse Gases was proposed by New Zealand at the United Nations Framework Convention on Climate Change Conference of the Parties (COP) in Copenhagen in 2009 and developed in partnership with the United States. This alliance now includes 32 member count...

  17. 76 FR 47391 - Mandatory Reporting of Greenhouse Gases

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-04

    ...EPA is proposing to amend specific provisions in the Mandatory Reporting of Greenhouse Gases Rule to correct certain technical and editorial errors that have been identified since promulgation and to clarify or propose amendments to certain provisions that have been the subject of questions from reporting entities. These proposed changes include additional information to clarify compliance......

  18. Greenhouse gases from wastewater treatment - A review of modelling tools.

    PubMed

    Mannina, Giorgio; Ekama, George; Caniani, Donatella; Cosenza, Alida; Esposito, Giovanni; Gori, Riccardo; Garrido-Baserba, Manel; Rosso, Diego; Olsson, Gustaf

    2016-05-01

    Nitrous oxide, carbon dioxide and methane are greenhouse gases (GHG) emitted from wastewater treatment that contribute to its carbon footprint. As a result of the increasing awareness of GHG emissions from wastewater treatment plants (WWTPs), new modelling, design, and operational tools have been developed to address and reduce GHG emissions at the plant-wide scale and beyond. This paper reviews the state-of-the-art and the recently developed tools used to understand and manage GHG emissions from WWTPs, and discusses open problems and research gaps. The literature review reveals that knowledge on the processes related to N2O formation, especially due to autotrophic biomass, is still incomplete. The literature review shows also that a plant-wide modelling approach that includes GHG is the best option for the understanding how to reduce the carbon footprint of WWTPs. Indeed, several studies have confirmed that a wide vision of the WWPTs has to be considered in order to make them more sustainable as possible. Mechanistic dynamic models were demonstrated as the most comprehensive and reliable tools for GHG assessment. Very few plant-wide GHG modelling studies have been applied to real WWTPs due to the huge difficulties related to data availability and the model complexity. For further improvement in GHG plant-wide modelling and to favour its use at large real scale, knowledge of the mechanisms involved in GHG formation and release, and data acquisition must be enhanced. PMID:26878638

  19. Modern inhalation anesthetics: Potent greenhouse gases in the global atmosphere

    NASA Astrophysics Data System (ADS)

    Vollmer, Martin K.; Rhee, Tae Siek; Rigby, Matt; Hofstetter, Doris; Hill, Matthias; Schoenenberger, Fabian; Reimann, Stefan

    2015-03-01

    Modern halogenated inhalation anesthetics undergo little metabolization during clinical application and evaporate almost completely to the atmosphere. Based on their first measurements in a range of environments, from urban areas to the pristine Antarctic environment, we detect a rapid accumulation and ubiquitous presence of isoflurane, desflurane, and sevoflurane in the global atmosphere. Over the past decade, their abundances in the atmosphere have increased to global mean mole fractions in 2014 of 0.097ppt, 0.30ppt, and 0.13ppt (parts per trillion, 10-12, in dry air), respectively. Emissions of these long-lived greenhouse gases inferred from the observations suggest a global combined release to the atmosphere of 3.1 ± 0.6 million t CO2 equivalent in 2014 of which ≈80% stems from desflurane. We also report on halothane, a previously widely used anesthetic. Its global mean mole fraction has declined to 9.2ppq (parts per quadrillion, 10-15) by 2014. However, the inferred present usage is still 280 ±120t yr-1.

  20. Inhomogeneous radiative forcing of homogeneous greenhouse gases

    NASA Astrophysics Data System (ADS)

    Huang, Yi; Tan, Xiaoxiao; Xia, Yan

    2016-03-01

    Radiative forcing of a homogeneous greenhouse gas (HGG) can be very inhomogeneous because the forcing is dependent on other atmospheric and surface variables. In the case of doubling CO2, the monthly mean instantaneous forcing at the top of the atmosphere is found to vary geographically and temporally from positive to negative values, with the range (-2.5-5.1 W m-2) being more than 3 times the magnitude of the global mean value (2.3 W m-2). The vertical temperature change across the atmospheric column (temperature lapse rate) is found to be the best single predictor for explaining forcing variation. In addition, the masking effects of clouds and water vapor also contribute to forcing inhomogeneity. A regression model that predicts forcing from geophysical variables is constructed. This model can explain more than 90% of the variance of the forcing. Applying this model to analyzing the forcing variation in the Climate Model Intercomparison Project Phase 5 models, we find that intermodel discrepancy in CO2 forcing caused by model climatology leads to considerable discrepancy in their projected change in poleward energy transport.

  1. Greenhouse gases mitigation options and strategies for Tanzania

    SciTech Connect

    Mwandosya, M.J.; Meena, H.E.

    1996-12-31

    Tanzania became a party to the United Nations Framework on Climate Change (UN FCCC) when she ratified the Convention in March, 1996. Now that Tanzania and other developing countries are Parties to the UN FCCC, compliance with its provisions is mandatory. The legal requirements therefore provide a basis for their participation in climate change studies and policy formulation. All parties to the Convention are required by Article 4.1 of the United Nations Convention on Climate Change (UN FCCC) to develop, periodically update, publish, and make available national inventories of anthropogenic emissions and removal of greenhouse gases that are not controlled by the Montreal Protocol. This study on possible options for the mitigation of greenhouse gases in Tanzania is a preliminary effort towards the fulfilment of the obligation. In order to fulfil their obligations under the UN FCCC and have a meaningful mitigation assessment, identification and quantification of anthropogenic sources of atmospheric emissions of greenhouse gases in the country was undertaken. In this respect, the study of anthropogenic emissions by source and removals by sink of GHGs in Tanzania was done with the main objective of increasing the quantity and quality of base-line data available in order to further scientific understanding of the relationship of greenhouse gas emissions to climate change. Furthermore, the study facilitated identification of national policy and technological options that could reduce the level of emissions in the country.

  2. Emissions Of Greenhouse Gases From Rice Agriculture

    SciTech Connect

    M. Aslam K. Khalil

    2009-07-16

    This project produced detailed data on the processes that affect methane and nitrous oxide emissions from rice agriculture and their inter-relationships. It defines the shifting roles and potential future of these gases in causing global warming and the benefits and tradeoffs of reducing emissions. The major results include: 1). Mechanisms and Processes Leading to Methane Emissions are Delineated. Our experiments have tested the standard model of methane emissions from rice fields and found new results on the processes that control the flux. A mathematical mass balance model was used to unravel the production, oxidation and transport of methane from rice. The results suggested that when large amounts of organic matter are applied, the additional flux that is observed is due to both greater production and reduced oxidation of methane. 2). Methane Emissions From China Have Been Decreasing Over the Last Two Decades. We have calculated that methane emissions from rice fields have been falling in recent decades. This decrease is particularly large in China. While some of this is due to reduced area of rice agriculture, the bigger effect is from the reduction in the emission factor which is the annual amount of methane emitted per hectare of rice. The two most important changes that cause this decreasing emission from China are the reduced use of organic amendments which have been replaced by commercial nitrogen fertilizers, and the increased practice of intermittent flooding as greater demands are placed on water resources. 3). Global Methane Emissions Have Been Constant For More Than 20 Years. While the concentrations of methane in the atmosphere have been leveling off in recent years, our studies show that this is caused by a near constant total global source of methane for the last 20 years or more. This is probably because as some anthropogenic sources have increased, others, such as the rice agriculture source, have fallen. Changes in natural emissions appear small

  3. 40 CFR 71.13 - Enforceable commitments for further actions addressing Greenhouse Gases (GHGs)

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... actions addressing Greenhouse Gases (GHGs) 71.13 Section 71.13 Protection of Environment ENVIRONMENTAL... § 71.13 Enforceable commitments for further actions addressing Greenhouse Gases (GHGs) (a) Definitions—(1) Greenhouse Gases (GHGs) means the air pollutant as defined in § 86.1818-12(a) of this chapter...

  4. 40 CFR 71.13 - Enforceable commitments for further actions addressing greenhouse gases (GHGs).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... actions addressing greenhouse gases (GHGs). 71.13 Section 71.13 Protection of Environment ENVIRONMENTAL... § 71.13 Enforceable commitments for further actions addressing greenhouse gases (GHGs). (a) Definitions—(1) Greenhouse Gases (GHGs) means the air pollutant as defined in § 86.1818-12(a) of this chapter...

  5. 40 CFR 71.13 - Enforceable commitments for further actions addressing Greenhouse Gases (GHGs)

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... actions addressing Greenhouse Gases (GHGs) 71.13 Section 71.13 Protection of Environment ENVIRONMENTAL... § 71.13 Enforceable commitments for further actions addressing Greenhouse Gases (GHGs) (a) Definitions. (1) Greenhouse Gases (GHGs) means the air pollutant as defined in § 86.1818-12(a) of this chapter...

  6. 40 CFR 71.13 - Enforceable commitments for further actions addressing Greenhouse Gases (GHGs)

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... actions addressing Greenhouse Gases (GHGs) 71.13 Section 71.13 Protection of Environment ENVIRONMENTAL... § 71.13 Enforceable commitments for further actions addressing Greenhouse Gases (GHGs) (a) Definitions—(1) Greenhouse Gases (GHGs) means the air pollutant as defined in § 86.1818-12(a) of this chapter...

  7. 40 CFR 71.13 - Enforceable commitments for further actions addressing greenhouse gases (GHGs).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... actions addressing greenhouse gases (GHGs). 71.13 Section 71.13 Protection of Environment ENVIRONMENTAL... § 71.13 Enforceable commitments for further actions addressing greenhouse gases (GHGs). (a) Definitions—(1) Greenhouse Gases (GHGs) means the air pollutant as defined in § 86.1818-12(a) of this chapter...

  8. Greenhouse effect of trace gases, 1970-1980

    NASA Technical Reports Server (NTRS)

    Lacis, A.; Hansen, J.; Lee, P.; Lebedeff, S.; Mitchell, T.

    1981-01-01

    Increased abundances were measured for several trace atmospheric gases in the decade 1970-1980. The equilibrium greenhouse warming for the measured increments of CH4, chlorofluorocarbons and N2O is between 50% and 100% of the equilibrium warming for the measured increase of atmospheric CO2 during the same 10 years. The combined warming of CO2 and trace gases should exceed natural global temperature variability in the 1980's and cause the global mean temperature to rise above the maximum of the late 1930's.

  9. Comparisons of aircraft measurements of greenhouse gases with GOSAT data

    NASA Astrophysics Data System (ADS)

    Tanaka, T.; Yates, E. L.; Iraci, L. T.; Loewenstein, M.; Gore, W.; Tadic, J.; Lopez, J. P.; Shiomi, K.; Kawakami, S.; kuze, A.; Yokota, T.

    2013-12-01

    Vertical profiles of greenhouse gases (GHGs) and ozone were measured using the Alpha Jet research aircraft as part of the Alpha Jet Atmospheric eXperiment (AJAX). Airborne instruments measuring GHGs (Picarro Inc. G2301-m) and ozone (2B Technologies Inc., model 205) are installed in a wing pod and operated from NASA Ames Research Center at Moffett Field, CA (37.415°N, 120.050°W). The in situ measurement instruments mounted on the aircraft yield precise and accurate vertical profiles of atmospheric GHGs and ozone. The purpose of this work is to validate GOSAT data and estimate from Alpha Jet measurements the contribution of GHGs from urban areas. We show the result of comparison of GOSAT and Alpha Jet measurements over Railroad Valley, NV and urban areas in Northern California. The Alpha Jet aircraft performs a measurement over the Railroad Valley (RRV) desert playa, Nevada (38.497°N, 115.691°W, 1437m above mean sea level) once a month for the comparison with Greenhouse gases Observing Satellite (GOSAT) measurements from 2011. The GOSAT was developed to measure concentrations of CO2 and CH4 from space and has been in operation from 2009. The instruments onboard GOSAT are the Thermal And Near-infrared Sensor for carbon Observation Fourier Transform Spectrometer (TANSO-FTS) and the TANSO Cloud and Aerosol Imager (TANSO-CAI) (Kuze et al., 2009). The RRV playa is a flat, high altitude desert site and an area where local sources and sinks of carbon-species are expected to be minimal. The playa has virtually no vegetation and an overall size of 15 km× 15 km, which includes GOSAT's field of view. Reference Akihiko Kuze, Hiroshi Suto, Masakatsu Nakajima, and Takashi Hamazaki. Thermal and near infrared sensor for carbon observation Fourier-transform spectrometer on the Greenhouse Gases Observing Satellite for greenhouse gases monitoring. App. Opt., 48, 6716-6733, 2009.

  10. Position statement on climate change and greenhouse gases

    NASA Astrophysics Data System (ADS)

    Adopted by Council December 1998Atmospheric concentrations of carbon dioxide and other greenhouse gases have substantially increased as a consequence of fossil fuel combustion and other human activities. These elevated concentrations of greenhouse gases are predicted to persist in the atmosphere for times ranging to thousands of years. Increasing concentrations of carbon dioxide and other greenhouse gases affect the Earth-atmosphere energy balance, enhancing the natural greenhouse effect and thereby exerting a warming influence at the Earth's surface. Although greenhouse gas concentrations and their climatic influences are projected to increase, the detailed response of the system is uncertain. Principal sources of this uncertainty are the climate system's inherent complexity and natural variability.The increase in global mean surface temperatures over the past 150 years appears to be unusual in the context of the last few centuries, but it is not clearly outside the range of climate variability of the last few thousand years. The geologic record of the more distant past provides evidence of larger climate variations associated with changes in atmospheric carbon dioxide. These changes appear to be consistent with present understanding of the radiative properties of carbon dioxide and the influence of climate on the carbon cycle.There is no known geologic precedent for the transfer of carbon from the Earth's crust to atmospheric carbon dioxide, in quantities comparable to the burning of fossil fuels, without simultaneous changes in other parts of the carbon cycle and climate system.This close coupling between atmospheric carbon dioxide and climate suggests that a change in one would in all likelihood be accompanied by a change in the other.

  11. Emissions of greenhouse gases in the United States 1996

    SciTech Connect

    1997-10-01

    The Energy Information Administration (EIA) is required by the Energy Policy Act of 1992 to prepare a report on aggregate US national emissions of greenhouse gases for the period 1987--1990, with annual updates thereafter. This report is the fifth annual update, covering national emissions over the period 1989--1995, with preliminary estimates of emissions for 1996. The estimates contained in this report have been revised from those in last year`s report. Emissions estimates for carbon dioxide are reported in metric tons of carbon; estimates for other gases are reported in metric tons of gas. Chapter 1 of this report briefly recapitulates some background information about global climate change and the greenhouse effect and discusses important recent developments in global climate change activities. Chapter 2 through 6 cover emissions of carbon dioxide, methane, nitrous oxide, halocarbons, and criteria pollutants, respectively. Chapter 7 describes potential sequestration and emissions of greenhouse gases as a result of land use changes. Five appendixes are included with this report. 216 refs., 11 figs., 38 tabs.

  12. Response of Thermospheric Hydrogen to Solar Variability and Greenhouse Gases

    NASA Astrophysics Data System (ADS)

    Nossal, S. M.; Qian, L.; Solomon, S. C.; Burns, A. G.; Wang, W.; Mierkiewicz, E. J.; Roesler, F. L.; Woodward, R. C., Jr.

    2015-12-01

    Geocoronal hydrogen forms the upper boundary of the Earth's HOx chemisty and is a byproduct of methane and water vapor below. We will discuss observational and modeling studies of the upper atmospheric hydrogen response to the solar cycle and increases in greenhouse gases. The Wisconsin Northern hemisphere hydrogen airglow data set spans over two solar cycles. These data show a statistically significant solar cycle variation and a possible increase in intensity between successive solar maximum periods. We will discuss these data in the context of recent modeling studies with a single-column version of the Thermosphere-Ionosphere-Mesosphere-Electrodynamics General Circulation Model. We investigate mechanisms associated with the solar cycle and greenhouse gas forcing of hydrogen by separately doubling carbon dioxide and methane, as well as doubling both together. These simulations indicate that carbon dioxide cooling, as well as methane changes to the source species for hydrogen, both lead to predicted increases in the upper thermospheric hydrogen density and that the response of hydrogen to greenhouse gases depends on the phase of the solar cycle. However, the effect of greenhouse gas doubling is not as large as the modeled solar cycle variability of thermospheric hydrogen. I will discuss results from these simulations and comparisons to observations.

  13. The terrestrial biosphere as a net source of greenhouse gases to the atmosphere

    DOE PAGESBeta

    Tian, Hanqin; Lu, Chaoqun; Ciais, Philippe; Michalak, Anna M.; Canadell, Josep G.; Saikawa, Eri; Huntzinger, Deborah N.; Gurney, Kevin R; Sitch, Stephen; Zhang, Bowen; et al

    2016-03-09

    The terrestrial biosphere can release or absorb the greenhouse gases, carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), and therefore has an important role in regulating atmospheric composition and climate1. Anthropogenic activities such as land-use change, agriculture and waste management have altered terrestrial biogenic greenhouse gas fluxes, and the resulting increases in methane and nitrous oxide emissions in particular can contribute to climate change2, 3. The terrestrial biogenic fluxes of individual greenhouse gases have been studied extensively4, 5, 6, but the net biogenic greenhouse gas balance resulting from anthropogenic activities and its effect on the climate system remains uncertain.more » Here we use bottom-up (inventory, statistical extrapolation of local flux measurements, and process-based modelling) and top-down (atmospheric inversions) approaches to quantify the global net biogenic greenhouse gas balance between 1981 and 2010 resulting from anthropogenic activities and its effect on the climate system. We find that the cumulative warming capacity of concurrent biogenic methane and nitrous oxide emissions is a factor of about two larger than the cooling effect resulting from the global land carbon dioxide uptake from 2001 to 2010. This results in a net positive cumulative impact of the three greenhouse gases on the planetary energy budget, with a best estimate (in petagrams of CO2 equivalent per year) of 3.9 ± 3.8 (top down) and 5.4 ± 4.8 (bottom up) based on the GWP100 metric (global warming potential on a 100-year time horizon). Lastly, our findings suggest that a reduction in agricultural methane and nitrous oxide emissions, particularly in Southern Asia, may help mitigate climate change.« less

  14. The terrestrial biosphere as a net source of greenhouse gases to the atmosphere

    NASA Astrophysics Data System (ADS)

    Tian, Hanqin; Lu, Chaoqun; Ciais, Philippe; Michalak, Anna M.; Canadell, Josep G.; Saikawa, Eri; Huntzinger, Deborah N.; Gurney, Kevin R.; Sitch, Stephen; Zhang, Bowen; Yang, Jia; Bousquet, Philippe; Bruhwiler, Lori; Chen, Guangsheng; Dlugokencky, Edward; Friedlingstein, Pierre; Melillo, Jerry; Pan, Shufen; Poulter, Benjamin; Prinn, Ronald; Saunois, Marielle; Schwalm, Christopher R.; Wofsy, Steven C.

    2016-03-01

    The terrestrial biosphere can release or absorb the greenhouse gases, carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), and therefore has an important role in regulating atmospheric composition and climate. Anthropogenic activities such as land-use change, agriculture and waste management have altered terrestrial biogenic greenhouse gas fluxes, and the resulting increases in methane and nitrous oxide emissions in particular can contribute to climate change. The terrestrial biogenic fluxes of individual greenhouse gases have been studied extensively, but the net biogenic greenhouse gas balance resulting from anthropogenic activities and its effect on the climate system remains uncertain. Here we use bottom-up (inventory, statistical extrapolation of local flux measurements, and process-based modelling) and top-down (atmospheric inversions) approaches to quantify the global net biogenic greenhouse gas balance between 1981 and 2010 resulting from anthropogenic activities and its effect on the climate system. We find that the cumulative warming capacity of concurrent biogenic methane and nitrous oxide emissions is a factor of about two larger than the cooling effect resulting from the global land carbon dioxide uptake from 2001 to 2010. This results in a net positive cumulative impact of the three greenhouse gases on the planetary energy budget, with a best estimate (in petagrams of CO2 equivalent per year) of 3.9 ± 3.8 (top down) and 5.4 ± 4.8 (bottom up) based on the GWP100 metric (global warming potential on a 100-year time horizon). Our findings suggest that a reduction in agricultural methane and nitrous oxide emissions, particularly in Southern Asia, may help mitigate climate change.

  15. The terrestrial biosphere as a net source of greenhouse gases to the atmosphere.

    PubMed

    Tian, Hanqin; Lu, Chaoqun; Ciais, Philippe; Michalak, Anna M; Canadell, Josep G; Saikawa, Eri; Huntzinger, Deborah N; Gurney, Kevin R; Sitch, Stephen; Zhang, Bowen; Yang, Jia; Bousquet, Philippe; Bruhwiler, Lori; Chen, Guangsheng; Dlugokencky, Edward; Friedlingstein, Pierre; Melillo, Jerry; Pan, Shufen; Poulter, Benjamin; Prinn, Ronald; Saunois, Marielle; Schwalm, Christopher R; Wofsy, Steven C

    2016-03-10

    The terrestrial biosphere can release or absorb the greenhouse gases, carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O), and therefore has an important role in regulating atmospheric composition and climate. Anthropogenic activities such as land-use change, agriculture and waste management have altered terrestrial biogenic greenhouse gas fluxes, and the resulting increases in methane and nitrous oxide emissions in particular can contribute to climate change. The terrestrial biogenic fluxes of individual greenhouse gases have been studied extensively, but the net biogenic greenhouse gas balance resulting from anthropogenic activities and its effect on the climate system remains uncertain. Here we use bottom-up (inventory, statistical extrapolation of local flux measurements, and process-based modelling) and top-down (atmospheric inversions) approaches to quantify the global net biogenic greenhouse gas balance between 1981 and 2010 resulting from anthropogenic activities and its effect on the climate system. We find that the cumulative warming capacity of concurrent biogenic methane and nitrous oxide emissions is a factor of about two larger than the cooling effect resulting from the global land carbon dioxide uptake from 2001 to 2010. This results in a net positive cumulative impact of the three greenhouse gases on the planetary energy budget, with a best estimate (in petagrams of CO2 equivalent per year) of 3.9 ± 3.8 (top down) and 5.4 ± 4.8 (bottom up) based on the GWP100 metric (global warming potential on a 100-year time horizon). Our findings suggest that a reduction in agricultural methane and nitrous oxide emissions, particularly in Southern Asia, may help mitigate climate change. PMID:26961656

  16. Emissions of greenhouse gases in the United States 1995

    SciTech Connect

    1996-10-01

    This is the fourth Energy Information Administration (EIA) annual report on US emissions of greenhouse gases. This report presents estimates of US anthropogenic (human-caused) emissions of carbon dioxide, methane, nitrous oxide, and several other greenhouse gases for 1988 through 1994. Estimates of 1995 carbon dioxide, nitrous oxide, and halocarbon emissions are also provided, although complete 1995 estimates for methane are not yet available. Emissions of carbon dioxide increased by 1.9% from 1993 to 1994 and by an additional 0.8% from 1994 to 1995. Most carbon dioxide emissions are caused by the burning of fossil fuels for energy consumption, which is strongly related to economic growth, energy prices, and weather. The US economy grew rapidly in 1994 and slowed in 1995. Estimated emissions of methane increased slightly in 1994, as a result of a rise in emissions from energy and agricultural sources. Estimated nitrous oxide emissions increased by 1.8% in 1995, primarily due to increased use of nitrogen fertilizers and higher output of chemicals linked to nitrous oxide emissions. Estimated emissions of hydrofluorocarbons (HFCs) and perfluorocarbons (PFCs), which are known to contribute to global warming, increased by nearly 11% in 1995, primarily as a result of increasing substitution for chlorofluorocarbons (CFCs). With the exception of methane, the historical emissions estimates presented in this report are only slightly revised from those in last year`s report.

  17. Validation of aerosols, reactive gases and greenhouse gases in the CAMS forecasts, analyses and reanalyses

    NASA Astrophysics Data System (ADS)

    Eskes, Henk; Basart, Sara; Blechschmidt, Anne; Chabrillat, Simon; Clark, Hannah; Cuevas, Emilio; Engelen, Richard; Kapsomenakis, John; Katragkou, Eleni; Mantzius Hansen, Kaj; Niemeijer, Sander; Ramonet, Michel; Schulz, Michael; Sudarchikova, Natalia; Wagner, Annette; Warneke, Thorsten

    2016-04-01

    The Atmosphere Monitoring Service of the European Copernicus Programme (CAMS) is an operational service providing analyses, reanalyses and daily forecasts of aerosols, reactive gases and greenhouse gases on a global scale, and air quality forecasts and reanalyses on a regional scale. CAMS is based on the systems developed during the European MACC I-II-III (Monitoring Atmospheric Composition and Climate) research projects. In CAMS data assimilation techniques are applied to combine in-situ and remote sensing observations with global and European-scale models of atmospheric reactive gases, aerosols and greenhouse gases. The global component is based on the Integrated Forecast System of the ECMWF, and the regional component on an ensemble of 7 European air quality models. CAMS is implemented by ECMWF, and the transition from MACC to CAMS is currently being implemented (2015-2016). CAMS has a dedicated validation activity, a partnership of 13 institutes co-ordinated by KNMI, to document the quality of the atmospheric composition products. In our contribution we discuss this validation activity, including the measurement data sets, validation requirements, the operational aspects, the upgrade procedure, the validation reports and scoring methods, and the model configurations and assimilation systems validated. Of special concern are the forecasts of high pollution concentration events (fires, dust storms, air pollution events, volcano ash and SO2). A few interesting validation results will be shown.

  18. Hyper-spectral observations of greenhouse gases in Three Gorges Reservoir Region, China

    NASA Astrophysics Data System (ADS)

    Wang, Ding Yi; Zhang, Chun-ming; Qin, Lin; Zhang, Lu; Wang, Xiang-hong; Li, Hong-qun; Yang, Fu-Mo; Chen, Gang-Cai; Wang, Shu-peng; Zhang, Xing-ying; Zhang, Peng

    The Three Gorges Reservoir (TGR) is the most ambitious hydroelectric and flood control project in human history. Its riparian zone has areas of ~300 km2 with water levels fluctuating between 175m above the sea in winter and 145m in summer, and is a special type of wetlands at the low water levels. These wetlands may release CO2 and CH4 with significantly spatial and temporal variations, and have been misleadingly described as a “methane menace” and caused a worldwide concern. A joint research program for TGR greenhouse gases monitoring is operated by several institutions and based at Yangtze Normal Univ. in Fuling of Chongqing. It is characterized by the combined satellite, airship, and ground-based hyper-spectral observations, which serve to simultaneously measure various eco-environmental parameters in a large area with high spatial and spectral resolutions, and to model the status and key dynamic processes of the TGR greenhouse gases. In this talk, the retrieval algorithm of the gas species from satellite near-infrared observations is discussed with special attentions paid to the mountainous and foggy TGR region. The distributions and variations of TGR greenhouse gases are studied by using the AIRS and SCIAMACHY monthly means of multiple years. The airship and ground-based observation system is outlined and expected to provide unique data needed to address the TGR environmental issues, and to evolve towards operational service.

  19. Enhancement of greenhouse gases associated with Canadian forest fire using multi sensor data

    NASA Astrophysics Data System (ADS)

    Singh, Rachita; Singh, Rachita; Chaturvedi, Ritu

    Forest fire is a common natural hazard that takes lives of people and billion dollar loss of properties almost every year. In the recent past frequency of forest fires have increased in Canada and throughout the world that is associated with the changes in land use and land cover practice. Multi sensor satellites are now capable in providing information about the land cover, atmosphere and meteorological parameters. The present paper deals with the multi sensor data (AIRS, MODIS, OMI AURA, TOMS) to study the changes in greenhouse and other gases (NOx, O3, CO, water vapor) and aerosol parameters. The detailed analysis of multi sensor data have shown elevated amount of greenhouse gases, total ozone column and aerosol optical depth during summer of 2004 at the time of Canadian forest fire compared to other years. The spatial distribution of greenhouse gas, aerosol optical depth and meteorological conditions are found to change after the onset of forest fire that shows the dynamic nature of the greenhouse gas and associated releases with the dispersion of the plume and smoke from the forest fire. The maximum changes are found from the surface up to a pressure level height 500 hPa, the change occur is found to be very much dependent on the distance from the source (forest fire location) and also on the meteorological conditions.

  20. Fluorinated greenhouse gases in the troposphere and stratosphere

    NASA Astrophysics Data System (ADS)

    Laube, Johannes C.; Gallacher, Eileen; Oram, David E.; Bönisch, Harald; Brenninkmeijer, Carl A. M.; Fraser, Paul J.; Röckmann, Thomas; Sturges, William T.

    2015-04-01

    Fluorinated organic trace gases in the atmosphere are almost exclusively thought to be of anthropogenic origin. In the case of fully fluorinated alkane and cycloalkane-derivatives their IR absorption features and very long atmospheric lifetimes (on the order of thousands of years) make them very strong greenhouse gases. We here present measurements of 10 of these perfluorocarbons in the UT/LS and stratosphere as derived from deployments of regular passenger aircraft (CARIBIC project, http://www.caribic-atmospheric.com/) and the high-altitude research aircraft M55 Geophysica. In combination with long-term tropospheric records obtained from the Cape Grim observatory, Tasmania, we estimate their impact on radiative forcing expressed as CO2-equivalents. As these gases have no significant sinks in the stratosphere they could also be suitable to derive an important transport diagnostic: the so-called mean age-of-air i.e. the average stratospheric transit time of an air parcel. We evaluate this possibility for all above-mentioned species and compare their characteristics with other inert species such as SF6, SF5CF3, and long-lived chlorofluorocarbons.

  1. 40 CFR 70.12 - Enforceable commitments for further actions addressing greenhouse gases (GHGs).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... six greenhouse gases: carbon dioxide, nitrous oxide, methane, hydrofluorocarbons, perfluorocarbons... measures developed by EPA (and adopted by the states) for reducing the permitting burden associated...

  2. Integrated model shows that atmospheric brown clouds and greenhouse gases have reduced rice harvests in India

    SciTech Connect

    Auffhammer, M.; Ramanathan, V.; Vincent, J.R.

    2007-12-26

    Previous studies have found that atmospheric brown clouds partially offset the warming effects of greenhouse gases. This finding suggests a tradeoff between the impacts of reducing emissions of aerosols and greenhouse gases. Results from a statistical model of historical rice harvests in India, coupled with regional climate scenarios from a parallel climate model, indicate that joint reductions in brown clouds and greenhouse gases would in fact have complementary, positive impacts on harvests. The results also imply that adverse climate change due to brown clouds and greenhouse gases contributed to the slowdown in harvest growth that occurred during the past two decades.

  3. Remote Sensing of Greenhouse Gases and Their Sources and Sinks

    NASA Astrophysics Data System (ADS)

    Butz, Andre; Babenhauserheide, Arne; Bertleff, Marco; Checa-Garcia, Ramiro; Hahne, Philipp; Hase, Frank; Klappenbach, Friedrich; Kostinek, Julian; Aben, Ilse; Hasekamp, Otto; Landgraf, Jochen; Galli, Andre; Basu, Sourish

    2014-06-01

    The man-made emissions of the greenhouse gases carbon dioxide (CO2) and methane (CH4) are considered the main drivers of anthropogenically induced climate change. Major uncertainties persist when it comes to quantifying regional scale surface fluxes of these gases or predicting the evolution of the relevant source/sink processes in a changing climate. Remote sensing of the atmospheric greenhouse gas concentrations from space-borne and ground-based platforms offers the opportunity to significantly advance our knowledge on spatial and temporal scales that are suitable for process attribution and mitigation actions. Overall, the most promising remote-sensing strategy exploits the rotational-vibrational absorption of CO2 and CH4 in sunlight penetrating the Earth's atmosphere. Typically, satellite sounders such as GOSAT (Greenhouse Gases Observing Satellite), OCO-2 (Orbiting Carbon Observatory), and S5P (Sentinel-5 precursor) as well as the ground-based spectrometers of the TCCON (Total Carbon Column Observing Network) cover various CO2, CH4, and O2 absorption bands in the near and shortwave infrared spectral range between 0.75 micron (13400cm-1) and 2.5 micron (4000cm-1). Accuracy of the inferred gas concentrations is contingent on the accuracy of the adopted spectroscopic parameters and spectroscopic models available in these spectral regions. Here, I will report on recent achievements and challenges within our greenhouse-gas remote-sensing activities mainly focusing on the GOSAT observational record. Since its launch in early 2009, the Fourier Transform Spectrometer onboard GOSAT delivers solar absorption spectra with good spectral resolution and high signal-to-noise. It has been shown that the CO2 and CH4 retrievals from these observations can achieve an accuracy on the order of fractions of a percent which makes them suitable for tracking regional scale source/sink processes and their response to climate events. In order to achieve the required accuracy, it is

  4. Vertical profiles of trapped greenhouse gases in Alaskan permafrost active layers before the spring thaw

    NASA Astrophysics Data System (ADS)

    Byun, Eunji; Yang, Ji-woong; Kim, Yongwon; Ahn, Jinho

    2015-04-01

    Seasonally frozen ground over permafrost is important in controlling annual greenhouse gas exchange between permafrost and atmosphere. Soil microbes decompose soil carbon and generate carbon dioxide and methane when they become activated. However, the actual greenhouse gas emission follows various efflux pathways. For example, seasonal freezing of the top soil layers can either restrain or press the gas emission from deeper layers. It has been reported that abrupt release of methane during spring is attributable to the emission of trapped gases that had failed to be released instantly after formation (1, 2). In order to examine the seasonally trapped greenhouse gases, we drilled five Alaskan permafrost cores before spring thaw; one from coastal tundra, two from typical boreal forests, one from area where fire occurred, and one from peat accumulated sites. Vertical profiles of carbon dioxide and methane concentrations were obtained with 5-10 cm depth intervals. We found methane peaks from two cores, indicating inhibition of methane efflux. We also analyzed organic carbon, nitrogen and water contents and compared them with the greenhouse gas profiles. We are continuing analysis for the soil temperature profiles of the sampling boreholes because the detailed temperature information might be related to microbial activity, and can be used as indirect indicators of soil water freezing and latent heat influences at some active layer depth (zero curtain effects). All the high-resolution analyses for subsurface environments may help to improve understanding greenhouse gas emission from permafrost regions. 1. Mastepanov M, et al. (2008) Large tundra methane burst during onset of freezing. Nature 456(7222):628-630. 2. Song C, et al. (2012) Large methane emission upon spring thaw from natural wetlands in the northern permafrost region. Environmental Research Letters 7(3):034009.

  5. Hydrothermal venting of greenhouse gases triggering Early Jurassic global warming

    NASA Astrophysics Data System (ADS)

    Svensen, Henrik; Planke, Sverre; Chevallier, Luc; Malthe-Sørenssen, Anders; Corfu, Fernando; Jamtveit, Bjørn

    2007-04-01

    The climate change in the Toarcian (Early Jurassic) was characterized by a major perturbation of the global carbon cycle. The event lasted for approximately 200,000 years and was manifested by a global warming of ˜ 6 °C, anoxic conditions in the oceans, and extinction of marine species. The triggering mechanisms for the perturbation and environmental change are however strongly debated. Here, we present evidence for a rapid formation and transport of greenhouse gases from the deep sedimentary reservoirs in the Karoo Basin, South Africa. Magmatic sills were emplaced during the initial stages of formation of the Early Jurassic Karoo Large Igneous Province, and had a profound influence on the fate of light elements in the organic-rich sedimentary host rocks. Total organic carbon contents and vitrinite reflectivity data from contact aureoles around the sills show that organic carbon was lost from the country rocks during heating. We present data from a new type of geological structures, termed breccia pipes, rooted in the aureoles within the shale of the Western Karoo Basin. The breccia pipes are cylindrical structures up to 150 meters in diameter and are mainly comprised of brecciated and baked black shale. Thousands of breccia pipes were formed due to gas pressure build-up during metamorphism of the shales, resulting in venting of greenhouse gases to the Toarcian atmosphere. Mass balance calculations constrained by new aureole data show that up to 1800 Gt of CO 2 was formed from organic material in the western Karoo Basin. About 15 times this amount of CO 2 (27,400 Gt) may have formed in the entire basin during the intrusive event. U-Pb dating of zircons from a sill related to many of the pipes demonstrates that the magma was emplaced 182.5 ± 0.4 million years ago. This supports a causal relationship between the intrusive volcanism, the gas venting, and the Toarcian global warming.

  6. 75 FR 26904 - Mandatory Reporting of Greenhouse Gases: Notice of Data Availability; Default Emission Factors...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-13

    ...The Environmental Protection Agency (EPA) is making available to the public draft default emission factors for semiconductor manufacturing refined process categories. On April 12, 2010 EPA published a proposed rule, Mandatory Reporting of Greenhouse Gases: Additional Sources of Fluorinated GHGs (75 FR 18652) which included proposed methods for monitoring and reporting greenhouse gases (GHGs)......

  7. Effects of elevated CO2 and agricultural management on flux of greenhouse gases from soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To evaluate the contribution of agriculture to climate change, flux of greenhouse gases from different cropping systems must be assessed. Measurement of soil efflux of greenhouse gases (CO2, N2O, and CH4) from conservation and conventional tillage systems that have been under the influence of eleva...

  8. 76 FR 61293 - Extension of Public Comment Period: Mandatory Reporting of Greenhouse Gases: Technical Revisions...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-04

    ... period on the action published on September 9, 2011 (76 FR 56010), Mandatory Reporting of Greenhouse... Gases: Technical Revisions to the Electronics Manufacturing and the Petroleum and Natural Gas Systems..., Mandatory Reporting of Greenhouse Gases: Technical Revisions to the Electronics Manufacturing and...

  9. Evolution of the global inequality in greenhouse gases emissions using multidimensional generalized entropy measures

    NASA Astrophysics Data System (ADS)

    Remuzgo, Lorena; Trueba, Carmen; Sarabia, José María

    2016-02-01

    Given the cumulative consequences of climate change, global concentration of greenhouse gases (GHGs) must be reduced; being inequality in per-capita emissions levels a problem to achieve a commitment by all countries. Thus, the evolution of carbon dioxide (CO2) emissions inequality has received special attention because CO2 is the most abundant GHG in the atmosphere. However, it is necessary to consider other gases to provide a real illustration of our starting point to achieve a multilateral agreement. In this paper, we study the evolution of global inequality in GHGs emissions during the period 1990-2011, considering the four main gases: CO2, methane (CH4), nitrous oxide (N2O) and fluorinated gases (F-gases). The data used in this analysis is taken from the World Resources Institute (2014) and the groups of countries are constructed according to the quantity of emissions that each country released into the atmosphere in the first year of study. For this purpose we use the multidimensional generalized entropy measures proposed by Maasoumi (1986) that can be decomposable into the between- and within-group inequality components. The biggest fall in inequality is observed when we attach more weight to the emissions transfers between the most polluting countries and assume a low substitution degree among pollutants. Finally, some economic policy implications are commented.

  10. 75 FR 12489 - Mandatory Reporting of Greenhouse Gases: Minor Harmonizing Changes to the General Provisions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-16

    ... AGENCY 40 CFR Part 98 RIN 2060-AQ15 Mandatory Reporting of Greenhouse Gases: Minor Harmonizing Changes to...: EPA is proposing to amend the general provisions for the Mandatory Greenhouse Gas (GHG) Reporting Rule... the Mandatory Greenhouse Gas Reporting Rule (40 CFR part 98, subpart A.) We have published a...

  11. 76 FR 22825 - Mandatory Reporting of Greenhouse Gases: Petroleum and Natural Gas Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-25

    ... AGENCY 40 CFR Parts 98 Mandatory Reporting of Greenhouse Gases: Petroleum and Natural Gas Systems AGENCY..., 2010 EPA promulgated Subpart W: Petroleum and Natural Gas Systems of the Greenhouse Gas Reporting Rule... outlined for calculating greenhouse gas emissions for the petroleum and natural gas systems source...

  12. Adaptation to Impacts of Greenhouse Gases on the Ocean (Invited)

    NASA Astrophysics Data System (ADS)

    Caldeira, K.

    2010-12-01

    Greenhouse gases are producing changes in ocean temperature and circulation, and these changes are already adversely affecting marine biota. Furthermore, carbon dioxide is absorbed by the oceans from the atmosphere, and this too is already adversely affecting some marine ecosystems. And, of course, sea-level rise affects both what is above and below the waterline. Clearly, the most effective approach to limit the negative impacts of climate change and acidification on the marine environment is to greatly diminish the rate of greenhouse gas emissions. However, there are other measures that can be taken to limit some of the negative effects of these stresses in the marine environment. Marine ecosystems are subject to multiple stresses, including overfishing, pollution, and loss of coastal wetlands that often serve as nurseries for the open ocean. The adaptive capacity of marine environments can be improved by limiting these other stresses. If current carbon dioxide emission trends continue, for some cases (e.g., coral reefs), it is possible that no amount of reduction in other stresses can offset the increase in stresses posed by warming and acidification. For other cases (e.g., blue-water top-predator fisheries), better fisheries management might yield improved population health despite continued warming and acidification. In addition to reducing stresses so as to improve the adaptive capacity of marine ecosystems, there is also the issue of adaptation in human communities that depend on this changing marine environment. For example, communities that depend on services provided by coral reefs may need to locate alternative foundations for their economies. The fishery industry will need to adapt to changes in fish abundance, timing and location. Most of the things we would like to do to increase the adaptive capacity of marine ecosystems (e.g., reduce fishing pressure, reduce coastal pollution, preserve coastal wetlands) are things that would make sense to do even in

  13. Thermospheric hydrogen response to increases in greenhouse gases

    NASA Astrophysics Data System (ADS)

    Nossal, S. M.; Qian, L.; Solomon, S. C.; Burns, A. G.; Wang, W.

    2016-04-01

    We investigated thermospheric hydrogen response to increase in greenhouse gases and the dependence of this response to solar activity, using a global mean version of the National Center for Atmospheric Research Thermosphere-Ionosphere-Mesosphere-Electrodynamics General Circulation Model. We separately doubled carbon dioxide (CO2) and methane (CH4) to study the influence of temperature and changes to source species for hydrogen. Our results indicate that both CO2 cooling and CH4 changes to the source species for hydrogen lead to predicted increases in the upper thermospheric hydrogen density. At 400 km, hydrogen increases ~30% under solar maximum and ~25% under solar minimum responding to doubling of CH4, indicating that hydrogen response to the source variation due to CH4 increase is relatively independent of solar activity. On the other hand, hydrogen response to doubling of CO2 highly depends on solar activity. At 400 km, doubling of CO2 results in an ~7% hydrogen increase at solar maximum, whereas it is ~25% at solar minimum. Consequently, at solar maximum, the predicted ~40% increase in atomic hydrogen in the upper thermosphere is primarily due to the source variation as a result of doubling of CH4, whereas at solar minimum, both cooling due to doubling of CO2 and the source variation due to doubling of CH4 have commensurate effects, resulting in an approximate 50% increase in the modeled upper thermospheric hydrogen.

  14. In-Situ Microbial Conversion of Sequestered Greenhouse Gases

    SciTech Connect

    Scott, A R; Mukhopadhyay, M; Balin, D F

    2012-09-06

    The objectives of the project are to use microbiological in situ bioconversion technology to convert sequestered or naturally-occurring greenhouse gases, including carbon dioxide and carbon monoxide, into methane and other useful organic compounds. The key factors affecting coal bioconversion identified in this research include (1) coal properties, (2) thermal maturation and coalification process, (3) microbial population dynamics, (4) hydrodynamics (5) reservoir conditions, and (6) the methodology of getting the nutrients into the coal seams. While nearly all cultures produced methane, we were unable to confirm sustained methane production from the enrichments. We believe that the methane generation may have been derived from readily metabolized organic matter in the coal samples and/or biosoluble organic material in the coal formation water. This raises the intriguing possibility that pretreatment of the coal in the subsurface to bioactivate the coal prior to the injection of microbes and nutrients might be possible. We determined that it would be more cost effective to inject nutrients into coal seams to stimulate indigenous microbes in the coal seams, than to grow microbes in fermentation vats and transport them to the well site. If the coal bioconversion process can be developed on a larger scale, then the cost to generate methane could be less than $1 per Mcf

  15. Generation and release of radioactive gases in LLW disposal facilities

    SciTech Connect

    Yim, M.S.; Simonson, S.A.

    1995-02-01

    The atmospheric release of radioactive gases from a generic engineered LLW disposal facility and its radiological impacts were examined. To quantify the generation of radioactive gases, detailed characterization of source inventory for carbon-14, tritium, iodine-129, krypton-85, and radon-222, was performed in terms of their activity concentrations; their distribution within different waste classes, waste forms and containers; and their subsequent availability for release in volatile or gaseous form. The generation of gases was investigated for the processes of microbial activity, radiolysis, and corrosion of waste containers and metallic components in wastes. The release of radionuclides within these gases to the atmosphere was analyzed under the influence of atmospheric pressure changes.

  16. Remote sensing of atmospheric greenhouse gases: bridging spatial scales

    NASA Astrophysics Data System (ADS)

    Humpage, N.; Boesch, H.; Parker, R.; Hewson, W.; Sembhi, H.; Somkuti, P.; Webb, A.; Palmer, P. I.; Feng, L.

    2015-12-01

    Observed atmospheric variations of greenhouse gases (GHG) are determined by surface-atmosphere exchange, and atmospheric chemistry and transport. These processes occur over a wide spectrum of spatial and temporal scales. Confronting atmospheric transport models and ultimately improving the fidelity of surface flux estimates demands an integrated observing system that captures these scales. We will discuss using data the role of GHG remote sensing instruments and argue that our ability to deploy them from the ground and to fly them on satellite, aircraft, and unmanned airborne vehicles (UAV) mean that they represent the ideal technology to bridge the observed scales of variability. We will discuss a five-year record of global-scale column observations of CO2 and CH4 from the Japanese GOSAT satellite instrument that is available from University of Leicester as part of the ESA Climate Change Initiative. We will showcase new CO2 and CH4 column data that was collected by our shortwave infrared spectrometer GHOST oboard the NASA Global Hak during a regional survey over the eastern Pacific during early spring 2015, which included coincident overpasses from GOSAT and the NASA OCO-2. These data are being used to test atmospheric transport models over remote regions and to help validate satellite observations over the oceans. We will also discuss GHOST data collected on the UK Dornier 226 research aircraft to measure local-scale measurements over Leicester city centre, a major power plant, and downwind of a controlled Cumbrian heathland fire. Finally, we will report preliminary results from a new ground-based Fourier transform spectrometer station at Harwell (80 km west of London). We anticipate that this site will eventually join the TCCON network, which has been used to validation of satellite observations.

  17. EVALUATION OF GREENHOUSE GASES EMISSION FROM SOILS AMENDED WITH SEWAGE SLUDGE

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increase in concentration of various greenhouse gases and their possible contributions to the global warming have received considerable research intrest. Agricultural practices, fossil fuel burning, deforestation, industrial emissions, and wetlands have contributed to atmospheric increases of carbo...

  18. Peru mitigation assessment of greenhouse gases: Sector -- Energy. Peru climate change country study; Final report

    SciTech Connect

    1996-08-01

    The aim of this study is to determine the Inventory and propose Greenhouse Gases Mitigation alternatives in order to face the future development of the country in a clean environmental setting without delaying the development process required to improve Peruvian standard of living. The main idea of this executive abstract is to show concisely the results of the Greenhouse Gases Mitigation for Peru in the period 1990--2015. The studies about mitigation for the Energy Sector are shown in this summary.

  19. Emissions of greenhouse gases in the United States, 1985--1990

    SciTech Connect

    Not Available

    1993-11-10

    The Earth`s capacity to support life depends on the moderating influences of gases that envelop the planet and warm its surface and protect it from harmful radiation. These gases are referred to as ``greenhouse gases.`` Their warming capacity, called ``the greenhouse effect,`` is essential to maintaining a climate hospitable to all plant, animal, and human life. In recent years, however, there has been increasing concern that human activity may be affecting the intricate balance between the Earth`s absorption of heat from the sun and its capacity to reradiate excess heat back into space. Emissions of greenhouse gases from human activities may be an important mechanism that affects global climate. Thus, research is intensifying to improve our understanding of the role human activities might play in influencing atmospheric concentrations of greenhouse gases. On the basis of scientific findings of the past few decades, the US Government and the international community at large are now taking steps toward stabilizing greenhouse gas emissions. This report contributes to that process. Mandated by Congress this report provides estimates of US emissions of the principal greenhouse gases--carbon dioxide, methane, nitrous oxide, chlorofluorcarbons, carbon monoxide, nitrogen oxides, and nonmethane volatile organic compounds. Estimates are for the period 1985 to 1990. Preliminary estimates for 1991 have also been included, whenever data were available.

  20. 75 FR 70254 - PSD and Title V Permitting Guidance for Greenhouse Gases

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-17

    ... under the GHG Tailoring Rule at 75 FR 31514 (June 3, 2010). EPA invites public comment on all aspects of... AGENCY PSD and Title V Permitting Guidance for Greenhouse Gases AGENCY: Environmental Protection Agency... the EPA has posted its guidance titled, ``PSD and Title V Permitting Guidance for Greenhouse...

  1. Global Mitigation Of Non-CO2 Greenhouse Gases: 2010-2030

    EPA Science Inventory

    This report illustrates the abatement potential of non-CO2 greenhouse gases, by sector and by region, from 2010-2030. This peer-reviewed update provides economists and policymakers with improved data to better understand the costs and opportunities for reducing non-CO2 greenhouse...

  2. Sun and dust versus greenhouse gases - An assessment of their relative roles in global climate change

    NASA Technical Reports Server (NTRS)

    Hansen, James E.; Lacis, Andrew A.

    1990-01-01

    Many mechanisms, including variations in solar radiation and atmospheric aerosol concentrations, compete with anthropogenic greenhouse gases as causes of global climate change. Comparisons of available data show that solar variability will not counteract greenhouse warming and that future observations will need to be made to quantify the role of tropospheric aerosols, for example.

  3. 77 FR 5514 - Mandatory Reporting of Greenhouse Gases: Notice of Preliminary Determinations Regarding Requests...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-03

    ...The EPA is announcing and explaining to the public its preliminary determinations regarding requests to use provisional global warming potentials for eight fluorinated greenhouse gases submitted by DuPont de Nemours, Inc. and Honeywell International for purposes of certain calculations in the Fluorinated Gas Production portion of the Mandatory Greenhouse Gas Reporting Rule. EPA's preliminary......

  4. 76 FR 73885 - Mandatory Reporting of Greenhouse Gases

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-29

    .... Environmental Protection Agency FR Federal Register GHG greenhouse gas GHGRP Greenhouse Gas Reporting Program... September 22, 2009 and published in the Federal Register on October 30, 2009 (74 FR 56260, October 30, 2009... notices were published in 2010 promulgating the requirements for subparts FF, II, and TT (75 FR...

  5. Managing agricultural greenhouse gases: The basis of GRACEnet

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since 2002, USDA Agricultural Research Service has been engaged in a national project called GRACEnet (Greenhouse gas Reduction through Agricultural Carbon Enhancement network). Goals of the project are to (1) evaluate soil organic carbon status and change, (2) assess net greenhouse gas emissions (...

  6. The relative roles of sulfate aerosols and greenhouse gases in climate forcing

    NASA Technical Reports Server (NTRS)

    Kiehl, J. T.; Briegleb, B. P.

    1993-01-01

    Calculations of the effects of both natural and anthropogenic tropospheric sulfate aerosols indicate that the aerosol climate forcing is sufficiently large in a number of regions of the Northern Hemisphere to reduce significantly the positive forcing from increased greenhouse gases. Summer sulfate aerosol forcing in the Northern Hemisphere completely offsets the greenhouse forcing over the eastern United States and central Europe. Anthropogenic sulfate aerosols contribute a globally averaged annual forcing of -0.3 watt per square meter as compared with +2.1 watts per square meter for greenhouse gases. Sources of the difference in magnitude with the previous estimate of Charlson et al. (1992) are discussed.

  7. Remote Sensing of Spatial Distributions of Greenhouse Gases in the Los Angles Basin

    NASA Technical Reports Server (NTRS)

    Fu, Dejian; Pongetti, Thomas J.; Sander, Stanley P.; Cheung, Ross; Stutz, Jochen; Park, Chang Hyoun; Li, Qinbin

    2011-01-01

    The Los Angeles air basin is a significant anthropogenic source of greenhouse gases and pollutants including CO2, CH4, N2O, and CO, contributing significantly to regional and global climate change. Recent legislation in California, the California Global Warming Solutions Act (AB32), established a statewide cap for greenhouse gas emissions for 2020 based on 1990 emissions. Verifying the effectiveness of regional greenhouse gas emissions controls requires high-precision, regional-scale measurement methods combined with models that capture the principal anthropogenic and biogenic sources and sinks. We present a novel approach for monitoring the spatial distributions of greenhouse gases in the Los Angeles basin using high resolution remote sensing spectroscopy. We participated in the CalNex 2010 campaign to provide greenhouse gas distributions for comparison between top-down and bottom-up emission estimates.

  8. Mechanisms of impact of greenhouse gases on the Earth's ozone layer in the Polar Regions

    NASA Astrophysics Data System (ADS)

    Zadorozhny, Alexander; Dyominov, Igor

    A numerical 2-D zonally averaged interactive dynamical radiative-photochemical model of the atmosphere including aerosol physics is used to examine the impact of the greenhouse gases CO2, CH4, and N2O on the future long-term changes of the Earth's ozone layer, in particular on its expected recovery after reduction of anthropogenic discharges of chlorine and bromine compounds into the atmosphere. The model allows calculating self-consistently diabatic circu-lation, temperature, gaseous composition of the troposphere and stratosphere at latitudes from the North to South Poles, as well as distribution of sulphate aerosol particles and polar strato-spheric clouds (PSCs) of types I and II. The scenarios of expected changes of the anthropogenic pollutants for the period from 1980 through 2050 are taken from Climate Change 2001. The processes, which determine the influence of anthropogenic growth of atmospheric abun-dance of the greenhouse gases on the long-term changes of the Earth's ozone layer in the Polar Regions, have been studied in details. Expected cooling of the stratosphere caused by increases of greenhouse gases, most importantly CO2, essentially influences the ozone layer by two ways: through temperature dependencies of the gas phase reaction rates and through enhancement of polar ozone depletion via increased PSC formation. The model calculations show that a weak-ness in efficiencies of all gas phase catalytic cycles of the ozone destruction due to cooling of the stratosphere is a dominant mechanism of the impact of the greenhouse gases on the ozone layer in Antarctic as well as at the lower latitudes. This mechanism leads to a significant acceleration of the ozone layer recovery here because of the greenhouse gases growth. On the contrary, the mechanism of the impact of the greenhouse gases on the ozone through PSC modification be-gins to be more effective in Arctic in comparison with the gas phase mechanism in springs after about 2020, which leads to retard

  9. EVERGREEN (envisat for environmental regulation of greenhouse gases)

    NASA Astrophysics Data System (ADS)

    Goede, A.

    The Kyoto Protocol calls for a quantitative reduction in greenhouse gas emissions by the year 2010. However global emissions, sources and sinks, are not accurately known. EVERGREEN, a recently selected project of the European Commission 5th Framework Programme for Environment and Sustainable Development, proposes to use the measurements of ENVISAT to produce improved greenhouse gas emission inventories. A combination of measurement and (inverse) modelling will be employed to derive emission estimates. Measurements include (partial) columns of CO2, CH4, N2O, CO, O3, NO2 and H2O. The focus will be on methane and carbon monoxide and on regional and seasonal variations. End-user involvement is arranged through participation of one coal industry and several national/European institutes, with responsibility for greenhouse gas issues. Specific objectives are: -Quality assessment and improvement of geenhouse (CO2,CH4) and related gasr (CO) measurements from ENVISAT instruments SCIAMACHY and MIPAS. -Assessment of the role of constituent parts in the radiative forcing based on ENVISAT measurements and atmospheric radiative transfer modelling -Quantification of greenhouse and related biospheric gas fluxes through inverse modelling constrained by ENVISAT measurements, with focus on CH4 and CO. -Provision of greenhouse gas emission data to National and European institutes as a value added product from ENVIS T .A The paper will present progress of the project achieved to date. The project will run until the end of 2005.

  10. Greenhouse gases accounting and reporting for waste management - A South African perspective

    SciTech Connect

    Friedrich, Elena; Trois, Cristina

    2010-11-15

    This paper investigates how greenhouse gases are accounted and reported in the waste sector in South Africa. Developing countries (including South Africa) do not have binding emission reduction targets, but many of them publish different greenhouse gas emissions data which have been accounted and reported in different ways. Results show that for South Africa, inventories at national and municipal level are the most important tools in the process of accounting and reporting greenhouse gases from waste. For the development of these inventories international initiatives were important catalysts at national and municipal levels, and assisted in developing local expertise, resulting in increased output quality. However, discrepancies in the methodology used to account greenhouse gases from waste between inventories still remain a concern. This is a challenging issue for developing countries, especially African ones, since higher accuracy methods are more data intensive. Analysis of the South African inventories shows that results from the recent inventories can not be compared with older ones due to the use of different accounting methodologies. More recently the use of Clean Development Mechanism (CDM) procedures in Africa, geared towards direct measurements of greenhouse gases from landfill sites, has increased and resulted in an improvement of the quality of greenhouse gas inventories at municipal level.

  11. Mitigation options for accidental releases of hazardous gases

    SciTech Connect

    Fthenakis, V.M.

    1995-05-01

    The objective of this paper is to review and compare technologies available for mitigation of unconfined releases of toxic and flammable gases. These technologies include: secondary confinement, deinventory, vapor barriers, foam spraying, and water sprays/monitors. Guidelines for the design and/or operation of effective post-release mitigation systems and case studies involving actual industrial mitigation systems are also presented.

  12. Carbon and Conservation: Cropping systems and greenhouse gases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Quantifying and predicting soil carbon sequestration and greenhouse gas emissions from agricultural systems have been research goals for numerous institutions, especially since the turn of the millennium. Cost, time, and politics are variables that have limited the rapid development of robust quant...

  13. Biomass burning and the production of greenhouse gases

    NASA Technical Reports Server (NTRS)

    Levine, Joel S.

    1991-01-01

    The present discussion of related aspects of biomass burning describes a technique for estimating the instantaneous emission of trace gases generated by such fires on the basis of satellite imagery, and notes that burning results in significantly enhanced biogenic emissions of N2O, NO, and CH4. Biomass burning therefore has both immediate and long-term impacts on the trace-gas content of the atmosphere. The effects of Kuwait's oil fires, which encompass both combustion gases and particulates, are compared with those of the more general problem.

  14. Release of radiogenic gases from the moon

    NASA Technical Reports Server (NTRS)

    Hodges, R. R., Jr.

    1977-01-01

    The rate of escape of Ar-40 from the moon is calculated from mass-spectrometer data obtained at the Apollo-17 landing site. It is shown that the rate of loss of Ar from the moon varies significantly over periods the order of one lunation and that the average loss rate is about 3 t/a, corresponding to about 6% of the present rate of Ar production by K decay within the moon. These features of the Ar loss-rate data are interpreted as evidence that this gas originates in the partially molten asthenosphere, which in turn requires that early differentiation only affected the outer 600 to 1,000 km of the moon, trapping significant amounts of radioactive materials in the present asthenosphere. The relationship between the venting of Ar and other radiogenic gases in the lunar atmosphere is discussed.

  15. A review of research on human activity induced climate change I. Greenhouse gases and aerosols

    NASA Astrophysics Data System (ADS)

    Wang, Mingxing; Liu, Qiang; Yang, Xin

    2004-06-01

    Extensive research on the sources and sinks of greenhouse gases, carbon cycle modeling, and the characterization of atmospheric aerosols has been carried out in China during the last 10 years or so. This paper presents the major achievements in the fields of emissions of greenhouse gases from agricultural lands, carbon cycle modeling, the characterization of Asian mineral dust, source identification of the precursors of the tropospheric ozone, and observations of the concentrations of atmospheric organic compounds. Special, more detailed information on the emissions of methane from rice fields and the physical and chemical characteristics of mineral aerosols are presented.

  16. Remote Sensing of Spatial Distributions of Greenhouse Gases in the Los Angeles Basin

    NASA Technical Reports Server (NTRS)

    Fu, Dejian; Sander, Stanley P.; Pongetti, Thomas J.; Cheung, Ross; Stutz, Jochen

    2010-01-01

    The Los Angeles air basin is a significant anthropogenic source of greenhouse gasses and pollutants including CO2, CH4, N2O, and CO, contributing significantly to regional and global climate change. Recent legislation in California, the California Global Warning Solutions Act (AB32), established a statewide cap for greenhouse gas emissions for 2020 based on 1990 emissions. Verifying the effectiveness of regional greenhouse gas emissions controls requires high-precision, regional-scale measurement methods combined with models that capture the principal anthropogenic and biogenic sources and sinks. We present a novel approach for monitoring the spatial distribution of greenhouse gases in the Los Angeles basin using high resolution remote sensing spectroscopy. We participated in the CalNex 2010 campaign to provide greenhouse gas distributions for comparison between top-down and bottom-up emission estimates.

  17. Effect of noble gases on an atmospheric greenhouse /Titan/.

    NASA Technical Reports Server (NTRS)

    Cess, R.; Owen, T.

    1973-01-01

    Several models for the atmosphere of Titan have been investigated, taking into account various combinations of neon and argon. The investigation shows that the addition of large amounts of Ne and/or Ar will substantially reduce the hydrogen abundance required for a given greenhouse effect. The fact that a large amount of neon should be present if the atmosphere is a relic of the solar nebula is an especially attractive feature of the models, because it is hard to justify appropriate abundances of other enhancing agents.

  18. Greenhouse gases in the corn-to-fuel ethanol pathway.

    SciTech Connect

    Wang, M. Q.

    1998-06-18

    Argonne National Laboratory (ANL) has applied its Greenhouse gas, Regulated Emissions and Energy in Transportation (GREET) full-fuel-cycle analysis model to examine greenhouse gas (GHG) emissions of corn-feedstock ethanol, given present and near-future production technology and practice. On the basis of updated information appropriate to corn farming and processing operations in the four principal corn- and ethanol-producing states (Illinois, Iowa, Minnesota, and Nebraska), the model was used to estimate energy requirements and GHG emissions of corn farming; the manufacture, transportation to farms, and field application of fertilizer and pesticide; transportation of harvested corn to ethanol plants; nitrous oxide emissions from cultivated cornfields; ethanol production in current average and future technology wet and dry mills; and operation of cars and light trucks using ethanol fuels. For all cases examined on the basis of mass emissions per travel mile, the corn-to-ethanol fuel cycle for Midwest-produced ethanol used in both E85 and E10 blends with gasoline outperforms conventional (current) and reformulated (future) gasoline with respect to energy use and GHG production. Also, GHG reductions (but not energy use) appear surprisingly sensitive to the value chosen for combined soil and leached N-fertilizer conversion to nitrous oxide. Co-product energy-use attribution remains the single key factor in estimating ethanol's relative benefits because this value can range from 0 to 50%, depending on the attribution method chosen.

  19. Documentation for Emissions of Greenhouse Gases in the United States 2008

    EIA Publications

    2011-01-01

    The Energy Policy Act of 1992 required the U.S. Energy Information Administration (EIA) to prepare an inventory of aggregate U.S. national emissions of greenhouse gases for the period 1987-1990, with annual updates thereafter. This report documents the methodology for the seventeenth annual inventory, covering national emissions over the period 1990-2008.

  20. Emission Potentials and Capacities of Sediments along Lower Savannah River for Greenhouse Gases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Emission of CH4 and other greenhouse gases (CO2, & N2O) is extremely variable in both space and time. It is well known fact that Savannah River receives effluents from variety of anthropogenic activities. These activities could have significant impact on the amount of available C and other chemical ...

  1. Advances in Data Processing for Open-path Fourier Transform Infrared Spectrometry of Greenhouse Gases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The automated quantification of three greenhouse gases, ammonia, methane and nitrous oxide, in the vicinity of a large dairy farm by open-path Fourier transform infrared (OP/FT-IR) spectrometry at intervals of 5 minutes is demonstrated. Spectral pretreatment, including the detection and correction ...

  2. 75 FR 18575 - Mandatory Reporting of Greenhouse Gases: Injection and Geologic Sequestration of Carbon Dioxide

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-12

    ...EPA is proposing a rule to require reporting on carbon dioxide (CO2) injection and geologic sequestration (GS). The proposed rulemaking does not require control of greenhouse gases (GHGs), rather it requires only monitoring and reporting of CO2 injection and geologic sequestration. EPA first proposed that suppliers of CO2 be subject to mandatory GHG reporting......

  3. Evaluation of Emission of Greenhouse Gases from Soils Amended with Sewage Sludge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increase in concentrations of various greenhouse gases originated by various human activities, including agricultural origin, could contribute to climate change. Anthropogenic activities such as cultivation of flooded rice and application of waste materials, such as sewage sludge which are rich in ...

  4. Photoacoustic Experimental System to Confirm Infrared Absorption Due to Greenhouse Gases

    ERIC Educational Resources Information Center

    Kaneko, Fumitoshi; Monjushiro, Hideaki; Nishiyama, Masayoshi; Kasai, Toshio; Harris, Harold H.

    2010-01-01

    An experimental system for detecting infrared absorption using the photoacoustic (PA) effect is described. It is aimed for use at high-school level to illustrate the difference in infrared (IR) absorption among the gases contained in the atmosphere in connection with the greenhouse effect. The experimental system can be built with readily…

  5. Greenhouse gases emission from municipal waste management: The role of separate collection.

    PubMed

    Calabrò, Paolo S

    2009-07-01

    The municipal solid waste management significantly contributes to the emission in the atmosphere of greenhouse gases (e.g. CO(2), CH(4), N(2)O) and therefore the management process from collection to treatment and disposal has to be optimized in order to reduce these emissions. In this paper, starting from the average composition of undifferentiated municipal solid waste in Italy, the effect of separate collection on greenhouse gases emissions from municipal waste management has been assessed. Different combinations of separate collection scenarios and disposal options (i.e. landfilling and incineration) have been considered. The effect of energy recovery from waste both in landfills and incinerators has also been addressed. The results outline how a separate collection approach can have a significant effect on the emission of greenhouse gases and how wise municipal solid waste management, implying the adoption of Best Available Technologies (i.e. biogas recovery and exploitation system in landfills and energy recovery system in Waste to Energy plants), can not only significantly reduce greenhouse gases emissions but, in certain cases, can also make the overall process a carbon sink. Moreover it has been shown that separate collection of plastic is a major issue when dealing with global warming relevant emissions from municipal solid waste management. PMID:19318239

  6. 75 FR 17331 - Public Hearings for the Mandatory Reporting Rule for Greenhouse Gases

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-06

    ... Reporting of Greenhouse Gases: Injection and Geologic Sequestration of Carbon Dioxide.'' These two notices... above certain threshold levels monitor and report emissions and carbon dioxide injection and geologic... Systems, proposed 40 CFR part 98, subpart W), EPA-HQ-OAR-2009-0926 (Carbon Dioxide Injection and...

  7. Field emissions of greenhouse gases from contrasting biofuel feedstock production systems under different N fertilization rates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Management choices (crop type, fertilization rate) could affect agricultural soil emissions of important temperature-forcing greenhouse gases (GHGs) such as carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O). Soil GHG emissions were measured in situ over the 2010 growing season at a biofu...

  8. Greenhouse gases emission from municipal waste management: The role of separate collection

    SciTech Connect

    Calabro, Paolo S.

    2009-07-15

    The municipal solid waste management significantly contributes to the emission in the atmosphere of greenhouse gases (e.g. CO{sub 2}, CH{sub 4}, N{sub 2}O) and therefore the management process from collection to treatment and disposal has to be optimized in order to reduce these emissions. In this paper, starting from the average composition of undifferentiated municipal solid waste in Italy, the effect of separate collection on greenhouse gases emissions from municipal waste management has been assessed. Different combinations of separate collection scenarios and disposal options (i.e. landfilling and incineration) have been considered. The effect of energy recovery from waste both in landfills and incinerators has also been addressed. The results outline how a separate collection approach can have a significant effect on the emission of greenhouse gases and how wise municipal solid waste management, implying the adoption of Best Available Technologies (i.e. biogas recovery and exploitation system in landfills and energy recovery system in Waste to Energy plants), can not only significantly reduce greenhouse gases emissions but, in certain cases, can also make the overall process a carbon sink. Moreover it has been shown that separate collection of plastic is a major issue when dealing with global warming relevant emissions from municipal solid waste management.

  9. 77 FR 10434 - Mandatory Reporting of Greenhouse Gases Rule: Confidentiality Determinations and Best Available...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-22

    ... including an extension of best available monitoring methods (76 FR 36339, June 22, 2011) and changes to... Reporting of Greenhouse Gases: Additional Sources of ] Fluorinated GHGs'' rule (75 FR 74774, hereinafter... authorities provided in CAA section 114. As stated in the preamble to the 2009 final rule (74 FR 56260)...

  10. 75 FR 18651 - Mandatory Reporting of Greenhouse Gases: Additional Sources of Fluorinated GHGs

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-12

    ...EPA is revising and supplementing its initial proposed actions to require reporting of fluorinated greenhouse gas (fluorinated GHG) emissions from certain source categories. Specifically, EPA is revising and supplementing its initial proposal to require reporting of fluorinated GHG emissions from electronics manufacturing, production of fluorinated gases, and use of electrical transmission and......

  11. Emissions of greenhouse gases in the United States, 1987--1994

    SciTech Connect

    1995-09-25

    The Energy Information Administration (EIA) is required by the Energy Policy Act of 1992 to prepare a report on aggregate US national emissions of greenhouse gases for the period 1987--1992, with annual updates thereafter. This is the third annual update report,covering national emissions over the period 1987--1993, with preliminary estimates of US carbon dioxide and halocarbon emissions for 1994. Calculating national aggregate emissions(or ``national inventories``) of greenhouse gases is a recently developed form of intellectual endeavor. Greenhouse gas emissions are rarely measured directly or reported to statistical agencies. Thus, to prepare emissions inventories usually requires inferring emissions indirectly from information collected for other purposes. Both the available information and the inferences drawn may be of varying reliability. Chapter 1 of this report briefly recapitulates some background information about global climate change and the greenhouse effect and discusses important recent developments in global climate change activities. Chapters 2 through 6 cover emissions of carbon dioxide, methane, nitrous oxide, halocarbons, and criteria pollutants, respectively. Chapter 7 describes potential sequestration and emissions of greenhouse gases as a result of land use changes.

  12. The contribution of drained organic soils to the globally emitted greenhouse gases and emission hotspots

    NASA Astrophysics Data System (ADS)

    Barthelmes, Alexandra; Couwenberg, John; Joosten, Hans

    2016-04-01

    Key words: organic soils, peatlands, drainage, emissions, globally Peatlands cover only 3% of the global land surface. Some 15% of these peatlands have been drained for agriculture, forestry and grazing, which leads to the release of huge amounts of carbon. The '2013 Supplement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories: Wetlands' (IPCC 2014) offers up-to-date default emission factors for different land use types on organic soil and thus enables proper reporting. For this, realistic area data of drained organic soils are needed at a national scale. We analysed the drained organic soil areas and related emissions as reported to the UNFCCC in 2014 for several Nordic-Baltic countries . The analysis revealed that the areas often seem to be underestimated and that several countries use outdated emission factors. The re-assessment of the drained area and the application of the IPCC (2014) default emission factors resulted in 5-10 x higher emissions from drained organic soils for some countries. Out of 9 Nordic-Baltic countries only 1 country seems to have overestimated the drainage related organic soil emissions. If adopting the default emission factors from IPCC (2014) globally, the emissions from drained and degrading organic soils (~ 1,600 Mt CO2-eq.) amount to almost double the amount of CO2 emissions from aviation, even when emissions from peat fires are not included . By far the top single emitter of drained peatland related greenhouse gases is Indonesia, followed by the European Union and Russia. 25 countries are together responsible for 95% of global emissions from peatland drainage, excluding fires. Fires raise the importance of particularly Indonesia and Russian Federation. In 25 countries emissions from peatland degradation are over 50% of the emissions from fossil fuels and cement production combined, hence peatland emissions are of national significance.

  13. Climate-chemical interactions and greenhouse effects of trace gases

    NASA Technical Reports Server (NTRS)

    Shi, Guang-Yu; Fan, Xiao-Biao

    1994-01-01

    A completely coupled one-dimensional radiative-convective (RC) and photochemical-diffusion (PC) model has been developed recently and used to study the climate-chemical interactions. The importance of radiative-chemical interactions within the troposphere and stratosphere has been examined in some detail. We find that increases of radiatively and/or chemically active trace gases such as CO2, CH4 and N2O have both the direct effects and the indirect effects on climate change by changing the atmospheric O3 profile through their interaction with chemical processes in the atmosphere. It is also found that the climatic effect of ozone depends strongly on its vertical distribution throughout the troposphere and stratosphere, as well on its column amount in the atmosphere.

  14. Green trees for greenhouse gases: a fair trade-off?

    PubMed

    Schmidt, C W

    2001-03-01

    While forests retain carbon in plants, detritus, and soils, utility companies spew it into the air as carbon dioxide, the main greenhouse gas behind global warming. Industrial carbon dioxide emissions aren't currently regulated by federal law, but a number of companies are trying to address the problem voluntarily by launching carbon sequestration programs in heavily forested countries, where carbon is contained in so-called sinks. But the November 2000 meeting of the Kyoto Protocol delegates in The Hague collapsed over the issue of the acceptability of carbon sinks as a source of carbon pollution credits, delivering what many see as a deathblow to the concept. At issue are a host of ecological and statistical questions, differing local land use practices, cultural factors, issues of verifiability, and even disagreement over definitions of basic terms such as "forest" Kyoto negotiators are gearing up for another round of discussions in Bonn in May 2001, and it is likely that the continuing debate over carbon sinks will dominate the agenda. PMID:11333205

  15. Greenhouse warming by minor gases on early Mars

    NASA Technical Reports Server (NTRS)

    Heinrich, M. N.; Thompson, W. R.; Sagan, C.

    1992-01-01

    The early atmospheres of Earth and Mars were non-oxidizing mixtures likely derived from volcanic outgassing of a silicate mantle, with some fraction of the volatiles also contributed by impacting comets and meteorites. Here the authors investigate the potential of minor atmospheric constituents produced by ultraviolet and auroral chemistry to contribute to the thermal opacity of early Earth and Mars atmospheres. Using a very simple two-stream thermal opacity model, the authors show that HCN at 10 parts per million (ppm) and N2O at 100 ppm can each block radiation in thermal infrared windows sufficiently to increase the surface temperature by 7 K separately, or 14 K together. Small quantities of other species are also produced in such experiments. Some of these have especially complex infrared spectra and should be further investigated for their potential to help close windows in the CO2 + H2O infrared transmission. Enhancement of greenhouse warming by minor atmospheric species different from those present in today's atmosphere may have played important roles in the climate of early Earth and Mars.

  16. Response of different Earth System Models to ramp-up/ramp-down greenhouse gases concentration trajectory

    NASA Astrophysics Data System (ADS)

    Sgubin, Giovanni; Swingedouw, Didier

    2013-04-01

    It has been relatively well established that, in the past, large abrupt and irreversible changes in the climate have consistently occurred when the climate system crossed certain thresholds. Given the massive amount of greenhouse gases released by human activities, which will further increase in the coming decades, it is crucial to evaluate the reversibility and inertia of the climate system in response to such an anthropogenic perturbation. Indeed, a few model projections have shown that the human contribution to greenhouse gases emission is likely to force the climate system towards potentially risky thresholds, which could dramatically alter the Earth's climate. In order to evaluate the robustness of such a scenario, we compare model results from 4 different state-of-the-art European EMSs (EC-EARTH, HadGEM2, IPSL-CM5-LR, MPI-ESM) in response to the same increase and decrease of anthropogenic forcing. More specifically, 95 years of ramp-up simulations based on the CMIP5 RCP8.5 scenario (where the radiative forcing value is gradually increased up to 8.5 W/m2) are followed by 95 years of ramp-down simulations (where the radiative value is reduced at the same rate down to its initial value). The response and the inertia of the climate system are investigated and the possibility of abrupt and/or (ir)reversible climatic changes are analysed in the different models. In particular, the behaviour of the Atlantic Meridional Overturning Circulation (AMOC) under the ramp-up/ramp-down is addressed and its relation to the evolution of other physical parameters is pointed out. Indeed, the stability of the AMOC, which is believed to lay in a monostable or bistable regime depending on the mean climate state, is controlled by different feedback mechanisms. A classical diagnostic for determining the transition between the single and multiple equilibria regime of the AMOC is the sign of the meridional freshwater transport at 30°S in the Atlantic. We therefore outline the response

  17. Noble gases released by vacuum crushing of EETA 79001 glass

    NASA Technical Reports Server (NTRS)

    Wiens, R. C.

    1988-01-01

    An EETA 79001 glass sample was crushed in a vacuum to observe the gases released. About 15 pct of the total gas concentrations were a mixture of a small amount of SPB-type gas with larger proportions of another air-like component. Less than 5 pct of the SPB gas was released by crushing, while 36-40 pct of the EETV (indigenous) gas was crush-released. The results are consistent with a siting of the EETV component in 10-100 micron vesicles seen in the glass. It is suggested that the SPB component is either in vesicles less than 6 microns in diameter or is primarily sited elsewhere.

  18. The state of greenhouse gases in the atmosphere using global observations through 2014

    NASA Astrophysics Data System (ADS)

    Tarasova, Oksana; Koide, Hiroshi; Dlugokencky, Ed

    2016-04-01

    We present results from the eleventh annual Greenhouse Gas Bulletin (http://www.wmo.int/pages/prog/arep/gaw/ghg/GHGbulletin.html) of the World Meteorological Organization (WMO). The results are based on research and observations performed by laboratories contributing to the WMO Global Atmosphere Watch (GAW) Programme (www.wmo.int/gaw). The Bulletin presents results of global analyses of observational data collected according to GAW recommended practices and submitted to the World Data Center for Greenhouse Gases (WDCGG). Bulletins are prepared by the WMO/GAW Scientific Advisory Group for Greenhouse Gases (http://www.wmo.int/pages/prog/arep/gaw/ScientificAdvisoryGroups.html) in collaboration with WDCGG. Observations used for global analysis are collected at more than 100 marine and terrestrial sites worldwide for CO2 and CH4 and at a smaller number of sites for other greenhouse gases. Globally averaged dry-air mole fractions of CO2, CH4 and N2O derived from this network reached new highs in 2014, at 397.7±0.1 ppm, 1833±1 ppb and 327.1±0.1 ppb respectively. These values constitute 143%, 254% and 121% of pre-industrial (before 1750) levels. The atmospheric increase of CO2 from 2013 to 2014 was 1.9 ppm, which is smaller than the increase from 2012 to 2013 and the average growth rate for the past decade (˜2.06 ppm per year), but larger than the average growth rate for the 1990s (˜1.5 ppm per year). Smaller growth in 2014 compared with other recent years is most likely related to a relatively small net change in large fluxes between the atmosphere and terrestrial biosphere. The rise of atmospheric CO2 has been only about a half of what is expected if all excess CO2 from burning fossil-fuels stayed in the air. The other half has been absorbed by the land biosphere and the oceans, leading to ocean acidification. For both CH4 and N2O the increases from 2013 to 2014 were larger than those observed from 2012 to 2013 and the mean rates over the past 10 years. The National

  19. Long Term Monitoring of Greenhouse Gases at NOAA - a Forty Year Record

    NASA Astrophysics Data System (ADS)

    Butler, J. H.

    2009-04-01

    NOAA's Earth System Research Laboratory and its precursor organizations have been monitoring trends and distributions of greenhouse gases and other climatically relevant constituents in the atmosphere for over 40 years (http://www.esrl.noaa.gov/gmd). The focus of these measurements has been to obtain reliable records of global trends and distributions, but the experimental design and use of these measurements have advanced over time with evolving scientific questions. In earlier days, measurements and data products were global in nature (e.g., Annual Greenhouse Gas Index, http://www.esrl.noaa.gov/gmd/aggi). Later, they addressed intra-hemispheric properties, continental contributions, and eventually regional sources and sinks (e.g., http://CarbonTracker.noaa.gov). Today, and into this century, scientific questions continue to progress and the observation systems will need to progress accordingly. Critical questions likely will center on greenhouse gas emission reduction efforts, ecosystem feedbacks, and climate surprises. Regional information will become increasingly important for supporting greenhouse gas emission reduction efforts, and this information must be accurate, precise, and without bias. With emerging diverse, regionalized efforts to monitor greenhouse gases, comparability of measurements and measurement systems becomes more important than ever. NOAA, with its long-standing networks and its role as the WMO Central Calibration Laboratory for the major greenhouse gases, is well positioned to provide the linkages necessary to assure that regional measurements are comparable. Policy-makers, businesses, and regulatory organizations will need the best information available for decision-making. This presentation will identify major, climate-relevant findings that have come from NOAA's networks and those of others over the past several decades and will address the long-term monitoring needs to support decision-making over the next decades as society begins to

  20. Note: Measurement system for the radiative forcing of greenhouse gases in a laboratory scale

    NASA Astrophysics Data System (ADS)

    Kawamura, Yoshiyuki

    2016-01-01

    The radiative forcing of the greenhouse gases has been studied being based on computational simulations or the observation of the real atmosphere meteorologically. In order to know the greenhouse effect more deeply and to study it from various viewpoints, the study on it in a laboratory scale is important. We have developed a direct measurement system for the infrared back radiation from the carbon dioxide (CO2) gas. The system configuration is similar with that of the practical earth-atmosphere-space system. Using this system, the back radiation from the CO2 gas was directly measured in a laboratory scale, which roughly coincides with meteorologically predicted value.

  1. Note: Measurement system for the radiative forcing of greenhouse gases in a laboratory scale.

    PubMed

    Kawamura, Yoshiyuki

    2016-01-01

    The radiative forcing of the greenhouse gases has been studied being based on computational simulations or the observation of the real atmosphere meteorologically. In order to know the greenhouse effect more deeply and to study it from various viewpoints, the study on it in a laboratory scale is important. We have developed a direct measurement system for the infrared back radiation from the carbon dioxide (CO2) gas. The system configuration is similar with that of the practical earth-atmosphere-space system. Using this system, the back radiation from the CO2 gas was directly measured in a laboratory scale, which roughly coincides with meteorologically predicted value. PMID:26827362

  2. Greenhouse effects due to man-made perturbations of trace gases

    NASA Technical Reports Server (NTRS)

    Wang, W. C.; Yung, Y. L.; Lacis, A. A.; Mo, T.; Hansen, J. E.

    1976-01-01

    Nitrous oxide, methane, ammonia, and a number of other trace constituents of the earth's atmosphere have infrared absorption bands in the spectral range from 7 to 14 microns. Despite their small amounts, these gases can have a significant effect on the thermal structure of the atmosphere by transmitting most of the thermal radiation from the earth's surface to the lower atmosphere. In the present paper, this greenhouse effect is computed for a number of trace gases. The nature and climatic implications of possible changes in the concentrations of N2O, CH4, NH3, and HNO3 are discussed.

  3. Remote Sensing of Greenhouse Gases by Combining Lidar and Optical Correlation Spectroscopy

    NASA Astrophysics Data System (ADS)

    Anselmo, C.; Thomas, B.; Miffre, A.; Francis, M.; Cariou, J. P.; Rairoux, P.

    2016-06-01

    In this contribution, we present recent work on the ability to achieve range-resolved greenhouse gases concentration measurements in the Earth's atmosphere (CH4, H2O) by combining broadband optical correlation spectroscopy (OCS) with lidar. We show that OCS-Lidar is a robust methodology, allowing trace gases remote sensing with a low dependence on the temperature and pressure-variation absorption cross section. Moreover, we evaluate, as an experimental proof, the water vapor profile in the planetary boundary layer using the 4ν 720 nm absorption band.

  4. Counteracting the climate effects of volcanic eruptions using short-lived greenhouse gases

    NASA Astrophysics Data System (ADS)

    Fuglestvedt, Jan S.; Samset, Bjørn H.; Shine, Keith P.

    2014-12-01

    A large volcanic eruption might constitute a climate emergency, significantly altering global temperature and precipitation for several years. Major future eruptions will occur, but their size or timing cannot be predicted. We show, for the first time, that it may be possible to counteract these climate effects through deliberate emissions of short-lived greenhouse gases, dampening the abrupt impact of an eruption. We estimate an emission pathway countering a hypothetical eruption 3 times the size of Mount Pinatubo in 1991. We use a global climate model to evaluate global and regional responses to the eruption, with and without counteremissions. We then raise practical, financial, and ethical questions related to such a strategy. Unlike the more commonly discussed geoengineering to mitigate warming from long-lived greenhouse gases, designed emissions to counter temporary cooling would not have the disadvantage of needing to be sustained over long periods. Nevertheless, implementation would still face significant challenges.

  5. Integrated Modeling & Development of Emission Scenarios for Methane and Key Indirect Greenhouse Gases

    SciTech Connect

    Jain, Atul K.

    2005-09-30

    This report outlines main accomplishments on the development of Emission inventories and Scenarios for Key Indirect Greenhouse Gases (CO, VOCs, NOx) and methane supported by Office of Science (BER), US Department of Energy. This research produced 3 journal articles, 1 book chapter, and 4 research articles/abstracts in conference proceedings. In addition, this grant supported two PhD students and one undergraduate student at UIUC.

  6. Potential effects of anthropogenic greenhouse gases on avian habitas and populations in the northern Great Plains

    SciTech Connect

    Larson, D.L. )

    1994-04-01

    Biotic response to the buildup of greenhouse gases in Earth's atmosphere is considerably more complex than an adjustment to changing temperature and precipitation. The fertilization effect CO[sub 2] has on some plants, the impact UVB radiation has on health and productivity of organisms, and the resulting changes in competitive balance and trophic structure must also be considered. The intent of this paper is to review direct and indirect effects of anthropogenic greenhouse gases on wildlife, and to explore possible effects on populations of birds and their habitats in the northern Great Plains. Many of the potential effects of increasing greenhouse gases, such as declining plant nutritional value, changes in timing of insect emergence, and fewer and saltier wetlands, foreshadow a decline in avian populations on the Great Plains. However, other possible effects such as increased drought resistance and water use efficiency of vegetation, longer growing seasons, and greater overall plant biomass promise at least some mitigation. Effects of multiple simultaneous perturbations such as can be expected under doubled CO[sub 2] scenarios will require substantial basic research to clarify. 113 refs., 1 fig.

  7. Potential effects of anthropogenic greenhouse gases on avian habitats and populations in the northern Great Plains

    USGS Publications Warehouse

    Larson, D.L.

    1994-01-01

    Biotic response to the buildup of greenhouse gases in Earth's atmosphere is considerably more complex than an adjustment to changing temperature and precipitation. The fertilization effect carbon dioxide has on some plants, the impact UVB radiation has on health and productivity of organisms, and the resulting changes in competitive balance and trophic structure must also be considered. The intent of this paper is to review direct and indirect effects of anthropogenic greenhouse gases on wildlife, and to explore possible effects on populations of birds and their habitats in the northern Great Plains.Many of the potential effects of increasing greenhouse gases, such as declining plant nutritional value, changes in timing of insect emergence, and fewer and saltier wetlands, foreshadow a decline in avian populations on the Great Plains. However, other possible effects such as increased drought resistance and water use efficiency of vegetation, longer growing seasons, and greater overall plant biomass promise at least some mitigation. Effects of multiple simultaneous perturbations such as can be expected under doubled carbon dioxide scenarios will require substantial basic research to clarify.

  8. Greenhouse gases, climate change and the transition from coal to low-carbon electricity

    NASA Astrophysics Data System (ADS)

    Myhrvold, N. P.; Caldeira, K.

    2012-03-01

    A transition from the global system of coal-based electricity generation to low-greenhouse-gas-emission energy technologies is required to mitigate climate change in the long term. The use of current infrastructure to build this new low-emission system necessitates additional emissions of greenhouse gases, and the coal-based infrastructure will continue to emit substantial amounts of greenhouse gases as it is phased out. Furthermore, ocean thermal inertia delays the climate benefits of emissions reductions. By constructing a quantitative model of energy system transitions that includes life-cycle emissions and the central physics of greenhouse warming, we estimate the global warming expected to occur as a result of build-outs of new energy technologies ranging from 100 GWe to 10 TWe in size and 1-100 yr in duration. We show that rapid deployment of low-emission energy systems can do little to diminish the climate impacts in the first half of this century. Conservation, wind, solar, nuclear power, and possibly carbon capture and storage appear to be able to achieve substantial climate benefits in the second half of this century; however, natural gas cannot.

  9. Voluntary reporting of greenhouse gases under Section 1605(b) of the Energy Policy Act of 1992

    SciTech Connect

    Holt, E. Jr.; Vernet, J.E. Jr.

    1994-12-31

    DOE is developing guidelines for the voluntary reporting of greenhouse gas emissions and their reductions, under Section 1605(b) of the Energy Policy Act of 1992. The establishment of this voluntary program should encourage the reduction of greenhouse gases while providing the opportunity to share innovative approaches to achieving such reductions. This social learning aspect is an important element of the program. In addition to greenhouse gas reductions achieved during a given year, reporters are encouraged to also report their actual emissions of such gases for 1987 through 1990. Due to the voluntary nature of this program, and the myriad differences among the potential reporting entities and possible uses for the data reported, the guidelines will need to be structured so as to maximize participation without compromising the usefulness of the data collected. Through a broad notice of inquiry, published in the Federal Register on July 27, 1993, the Department began seeking input into development of the guidelines. Subsequently, to gain a better understanding of the various sectors of the economy, six public workshops were held during the 1993. One workshop addressed institutional issues of potential interest to all sectors of the economy, with the other five workshops focusing more on matters of concern to specific sectors. These meetings were structured so as to provide broad representation from potential reporting entities along with public interest organizations. It is clear that there are significant variations among those reporting greenhouse information. Presently voluntary, the program will need flexibility to encourage broad participation.

  10. CARBONGASES: Retrieval and Analysis of Carbon Dioxide and Methane Greenhouse Gases from SCIAMACHY on Envisat

    NASA Astrophysics Data System (ADS)

    Schneising, O.; Buchwitz, M.; Reuter, M.; Bovensmann, H.; Burrows, J. P.

    2010-12-01

    Carbon dioxide (CO2) and methane (CH4) are the two most important anthropogenic greenhouse gases contributing to global climate change. Despite their importance our knowledge about their variable natural and anthropogenic sources and sinks has significant gaps. Satellite observations can add important global scale information on greenhouse gas sources and sinks provided the data are accurate and precise enough and are sensitive to the lowest atmospheric layers where the variability due to regional greenhouse gas sources and sinks are largest. SCIAMACHY onboard ENVISAT was the first and is now besides TANSO onboard GOSAT the only satellite instrument which covers important absorption bands of both gases in the near-infrared/shortwave- infrared (NIR/SWIR) spectral region. In nadir mode SCIAMACHY observes reflected and backscattered solar radiation. The daytime measurements are therefore very sensitive to near-surface greenhouse gas concentration changes except in case of significant cloud cover. The atmospheric greenhouse gas information is extracted from the SCIAMACHY spectra using the Weighting Function Modified Differential Optical Absorption Spectroscopy (WFM-DOAS or WFMD) algorithm developed at the Institute of Environmental Physics (IUP) of the University of Bremen, Germany. In the framework of the CARBONGASES project, which is part of the Changing Earth Science Network, the afore existing data set focussing on the first three full years of the ENVISAT mission (2003-2005) is improved and extended up to end of 2009 constituting seven years of greenhouse gas information derived from European Earth observation data and closing the gap to GOSAT. The status of this retrieval activity and first results are presented.

  11. Geologic Storage of Greenhouse Gases: Multiphase andNon-isothermal Effects, and Implications for Leakage Behavior

    SciTech Connect

    Pruess, Karsten

    2005-08-05

    Storage of greenhouse gases, primarily CO2, in geologic formations has been proposed as a means by which atmospheric emissions of such gases may be reduced (Bachu et al., 1994; Orr, 2004). Possible storage reservoirs currently under consideration include saline aquifers, depleted or depleting oil and gas fields, and unmineable coal seams (Baines and Worden, 2004). The amount of CO2 emitted from fossil-fueled power plants is very large, of the order of 30,000 tons per day (10 million tons per year) for a large 1,000 MW coal-fired plant (Hitchon,1996). In order to make a significant impact on reducing emissions, very large amounts of CO2 would have to be injected into subsurface formations, resulting in CO2 disposal plumes with an areal extent of order 100 km2 or more (Pruess et al., 2003). It appears inevitable, then, that such plumes will encounter imperfections in caprocks, such as fracture zones or faults, that would allow CO2 to leak from the primary storage reservoir. At typical subsurface conditions of temperature and pressure, CO2 is always less dense than aqueous fluids; thus buoyancy forces will tend to drive CO2 upward, towards the land surface, whenever adequate (sub-)vertical permeability is available. Upward migration of CO2 could also occur along wells, including pre-existing wells in sedimentary basins where oil and gas exploration and production may have been conducted (Celia et al., 2004), or along wells drilled as part of a CO2 storage operation. Concerns with leakage of CO2 from a geologic storage reservoir include (1) keeping the CO2 contained and out of the atmosphere, (2) avoiding CO2 entering groundwater aquifers, (3)asphyxiation hazard if CO2 is released at the land surface, and (4) the possibility of a self-enhancing runaway discharge, that may culminate in a ''pneumatic eruption'' (Giggenbach et al., 1991). The manner in which CO2 may leak from storage reservoirs must be understood in order to avoid hazards and design monitoring systems.

  12. Metrology for laser spectroscopic concentration and isotope ratio measurements of atmospheric greenhouse gases

    NASA Astrophysics Data System (ADS)

    Nwaboh, Javis; Manninen, Albert; Mohn, Joachim; Petersen, Jan C.; Werhahn, Olav; Ebert, Volker

    2015-04-01

    Continuous, accurate and precise measurements of greenhouse gases (GHG) and their isotopic composition are required to understand the global cycle as well as source and sink processes of these environmentally harmful substances. Part of the EMRP project HIGHGAS (Metrology for high-impact greenhouse gases) [1] focuses on spectroscopic methods for GHG isotopic composition measurements and optical transfer standards. Harmonization of terminologies and concepts used in the GHG measurement communities and the metrology community are in focus, especially for isotope ratio measurements by laser spectroscopy, where gas metrology is still at an early stage. The focus of the HIGHGAS project here is on 13C/12C and 18O/16O ratios in CO2, 15N/14N ratios in N2O and 13C/12C and 2H/1H ratios in CH4. As an alternative and complement of gas mixture standards, optical spectroscopic transfer standards for CO2 and CO shall be developed providing concentration results that are directly traceable to the international system of units (SI). Optical transfer standards offer an alternative in situ calibration route for other GHG measurement devices operating in the field. An optical transfer standard becomes particularly interesting when measuring sticky or reactive gases where cylinder-based reference gas mixtures may not be feasible. We present an approach to perform IR-spectrometry on gases with results directly traceable to the SI. This is crucial for the development of optical spectroscopic transfer standards providing SI-traceability to field measurements. Ideas for spectroscopic isotope ratio measurements aiming at SI-traceability will be discussed. Finally, we demonstrate the current performance and limitations of our measurement approaches and project possible solutions. Acknowledgement Parts of this work have been carried out within the European Metrology Research Programme (EMRP) ENV52 project-HIGHGAS (Metrology for high-impact greenhouse gases). The EMRP is jointly funded by the

  13. Greenhouse Gases

    MedlinePlus

    ... is involved is critically important to projecting future climate change, but as yet is still fairly poorly measured ... feedbacks in the climate system leading to global climate change. As yet, though the basics of the hydrological ...

  14. The Marginal Damage Costs of Different Greenhouse Gases: An Application of FUND

    SciTech Connect

    Waldhoff, Stephanie T.; Anthoff, David; Rose, Steven K.; Tol, Richard

    2014-01-01

    We use FUND 3.8 to estimate the social cost of four greenhouse gases: carbon dioxide, methane, nitrous oxide, and sulphur hexafluoride emissions. The damage potential for each gas—the ratio of the social cost of the non-carbon dioxide greenhouse gas to the social cost of carbon dioxide—is also estimated. The damage potentials are compared to several metrics, focusing in particular on the global warming potentials, which are frequently used to measure the trade-off between gases in the form of carbon dioxide equivalents. We find that damage potentials could be significantly higher than global warming potentials. This finding implies that previous papers have underestimated the relative importance of reducing non-carbon dioxide greenhouse gas emissions from an economic damage perspective. We show results for a range of sensitivity analyses: carbon dioxide fertilization on agriculture productivity, terrestrial feedbacks, climate sensitivity, discounting, equity weighting, and socioeconomic and emissions scenarios. The sensitivity of the results to carbon dioxide fertilization is a primary focus as it is an important element of climate change that has not been considered in much of the previous literature. We estimate that carbon dioxide fertilization has a large positive impact that reduces the social cost of carbon dioxide with a much smaller effect on the other greenhouse gases. As a result, our estimates of the damage potentials of methane and nitrous oxide are much higher compared to estimates that ignore carbon dioxide fertilization. As a result, our base estimates of the damage potential for methane and nitrous oxide that include carbon dioxide fertilization are twice their respective global warming potentials. Our base estimate of the damage potential of sulphur hexafluoride is similar to the one previous estimate, both almost three times the global warming potential.

  15. Long term changes in the ionosphere over Indian low latitudes: Impact of greenhouse gases

    NASA Astrophysics Data System (ADS)

    Sharma, Som; Chandra, H.; Beig, G.

    2015-06-01

    Increased concentration of greenhouse gases due to anthropogenic activities warm the troposphere and have a cooling effect in the middle and upper atmosphere. Ionospheric densities and heights are affected due to cooling. Carbon dioxide is one of the most dominant gases for the cause of long term ionospheric trends along with other radiatively active greenhouse gases. Regular ionospheric soundings are made over Ahmedabad (23.1°N, 72.7°E), since 1953. Long term changes in the ionosphere as a consequence of the cooling of the mesosphere and thermosphere due to the increased concentration of greenhouse gases have been studied. Ionospheric observations over Ahmedabad, a low latitude station in the anomaly crest region, for the years 1955-2003 are examined to study the long term changes in the critical frequencies of the various ionospheric layers and the height of the maximum ionization as characterized by hPF2. A decrease in foF2 (1.9 MHz for midday, 1.4 MHz for midnight) and hPF2 (18 km for midday, 17 km for midnight) during about five decades are noted. An increase is noted in foF1 (0.4 MHz). The foF2 data are also examined over an equatorial station Kodaikanal (10.2°N, 77.5°E), situated near the magnetic equator for the years 1960-1995 and a decrease of 0.5 MHz for midday and 0.7 MHz for midnight are noted in ~35 years.

  16. Underground Nuclear Explosions and Release of Radioactive Noble Gases

    NASA Astrophysics Data System (ADS)

    Dubasov, Yuri V.

    2010-05-01

    Over a period in 1961-1990 496 underground nuclear tests and explosions of different purpose and in different rocks were conducted in the Soviet Union at Semipalatinsk and anovaya Zemlya Test Sites. A total of 340 underground nuclear tests were conducted at the Semipalatinsk Test Site. One hundred seventy-nine explosions (52.6%) among them were classified as these of complete containment, 145 explosions (42.6%) as explosions with weak release of radioactive noble gases (RNG), 12 explosions (3.5%) as explosions with nonstandard radiation situation, and four excavation explosions with ground ejection (1.1%). Thirty-nine nuclear tests had been conducted at the Novaya Zemlya Test Site; six of them - in shafts. In 14 tests (36%) there were no RNG release. Twenty-three tests have been accompanied by RNG release into the atmosphere without sedimental contamination. Nonstandard radiation situation occurred in two tests. In incomplete containment explosions both early-time RNG release (up to ~1 h) and late-time release from 1 to 28 h after the explosion were observed. Sometimes gas release took place for several days, and it occurred either through tunnel portal or epicentral zone, depending on atmospheric air temperature.

  17. Global emissions of fluorinated greenhouse gases until 2050: technical mitigation potentials and costs

    NASA Astrophysics Data System (ADS)

    Purohit, Pallav; Hoglund-Isaksson, Lena

    2016-04-01

    The anthropogenic fluorinated (F-gases) greenhouse gas emissions have increased significantly in recent years and are estimated to rise further in response to increased demand for cooling services and the phase out of ozone-depleting substances (ODS) under the Montreal Protocol. F-gases (HFCs, PFCs and SF6) are potent greenhouse gases, with a global warming effect up to 22,800 times greater than carbon dioxide (CO2). This study presents estimates of current and future global emissions of F-gases, their technical mitigation potential and associated costs for the period 2005 to 2050. The analysis uses the GAINS model framework to estimate emissions, mitigation potentials and costs for all major sources of anthropogenic F-gases for 162 countries/regions, which are aggregated to produce global estimates. For each region, 18 emission source sectors with mitigation potentials and costs were identified. Global F-gas emissions are estimated at 0.7 Gt CO2eq in 2005 with an expected increase to about 3.6 Gt CO2eq in 2050. There are extensive opportunities to reduce emissions by over 95 percent primarily through replacement with existing low GWP substances. The initial results indicate that at least half of the mitigation potential is attainable at a cost of less than 20€ per t CO2eq, while almost 90 percent reduction is attainable at less than 100€ per t CO2eq. Currently, several policy proposals have been presented to amend the Montreal Protocol to substantially curb global HFC use. We analyze the technical potentials and costs associated with the HFC mitigation required under the different proposed Montreal Protocol amendments.

  18. Temperature and Precipitation Extremes in the United States: Quantifying the Responses to Aerosols and Greenhouse Gases

    NASA Astrophysics Data System (ADS)

    Mascioli, N. R.; Fiore, A. M.; Previdi, M. J.; Correa, G. J. P.

    2014-12-01

    Changes in extreme temperatures, heat waves, heavy rainfall events, and precipitation frequency can have adverse impacts on human health, air quality, agricultural productivity, and water resources. Using the aerosol only (AER) and greenhouse gas only (GHG) "single forcing" simulations (3 ensemble members each) from the GFDL CM3 chemistry-climate model, we investigate aerosol- versus greenhouse gas-induced changes in high temperature and precipitation extremes over the United States. We identify changes in these events from 1860 to 2005 and the associated large-scale dynamical conditions. Small changes in these extremes in the "all forcing" simulations reflect cancellations between the individual, opposite-signed effects of increasing anthropogenic aerosols and greenhouse gases. In AER, aerosols lead to lower extreme high temperatures and fewer warm spells over the western US (-2.1 K regional average; -20 days/year) and over the central and northeast US (-1.5 K; -12 days/year). In GHG, a similar but opposite-signed response pattern occurs (+2.7 K and +14 days/year over the western US; +2.5 K and +10 days/year in the central and northeast US). The similar spatial response patterns in AER versus GHG suggest a preferred regional mode of response that is largely independent of the regional distribution of the forcing agent. The influence of both greenhouse gases and aerosols on extreme high temperature is weakest in the southeast US, collocated with the observed "warming hole". No statistically significant change occurs in AER, and a warming of only +1.8 K occurs in GHG. Warming in this region continues to be muted over the 21st century under the RCP 8.5 scenario, with increases in extreme temperatures more than 1 K smaller than elsewhere. Aerosols induce decreases in the number of days per year with at least 10mm of precipitation (R10mm) over the eastern US in summer and winter and over the southern US in spring of roughly 1 day/year. In contrast, greenhouse gases

  19. GREENHOUSE GASES FROM SMALL-SCALE COMBUSTION IN DEVELOPING COUNTRIES -- A PILOT STUDY IN MANILA

    EPA Science Inventory

    The report gives results of sampling of combustion gases released by household cookstoves in Manila, Philippines. n a total of 24 samples, 14 cookstoves were tested, fueled by liquefied petroleum gas (LPG), kerosene (three kinds of stoves), charcoal, and wood. Five ambient sample...

  20. GREENHOUSE GASES FROM BIOMASS AND FOSSIL FUEL STOVES IN DEVELOPING COUNTRIES: A MANILA PILOT STUDY

    EPA Science Inventory

    Samples were taken of the combustion gases released by household cookstoves in Manila, Philippines. In a total of 24 samples, 14 cookstoves were tested. These were fueled by liquefied petroleum gas (LPG), kerosene (three kinds of stoves), charcoal, and wood. Ambient samples were ...

  1. Emissions of greenhouse gases from the use of transportation fuels and electricity. Volume 2: Appendixes A--S

    SciTech Connect

    DeLuchi, M.A. |

    1993-11-01

    This volume contains the appendices to the report on Emission of Greenhouse Gases from the Use of Transportation Fuels and Electricity. Emissions of methane, nitrous oxide, carbon monoxide, and other greenhouse gases are discussed. Sources of emission including vehicles, natural gas operations, oil production, coal mines, and power plants are covered. The various energy industries are examined in terms of greenhouse gas production and emissions. Those industries include electricity generation, transport of goods via trains, trucks, ships and pipelines, coal, natural gas and natural gas liquids, petroleum, nuclear energy, and biofuels.

  2. Carbon Dioxide Separation from Flue Gases: A Technological Review Emphasizing Reduction in Greenhouse Gas Emissions

    PubMed Central

    Songolzadeh, Mohammad; Soleimani, Mansooreh; Takht Ravanchi, Maryam; Songolzadeh, Reza

    2014-01-01

    Increasing concentrations of greenhouse gases (GHGs) such as CO2 in the atmosphere is a global warming. Human activities are a major cause of increased CO2 concentration in atmosphere, as in recent decade, two-third of greenhouse effect was caused by human activities. Carbon capture and storage (CCS) is a major strategy that can be used to reduce GHGs emission. There are three methods for CCS: pre-combustion capture, oxy-fuel process, and post-combustion capture. Among them, post-combustion capture is the most important one because it offers flexibility and it can be easily added to the operational units. Various technologies are used for CO2 capture, some of them include: absorption, adsorption, cryogenic distillation, and membrane separation. In this paper, various technologies for post-combustion are compared and the best condition for using each technology is identified. PMID:24696663

  3. A Group Increment Scheme for Infrared Absorption Intensities of Greenhouse Gases

    NASA Technical Reports Server (NTRS)

    Kokkila, Sara I.; Bera, Partha P.; Francisco, Joseph S.; Lee, Timothy J.

    2012-01-01

    A molecule's absorption in the atmospheric infrared (IR) window (IRW) is an indicator of its efficiency as a greenhouse gas. A model for estimating the absorption of a fluorinated molecule within the IRW was developed to assess its radiative impact. This model will be useful in comparing different hydrofluorocarbons and hydrofluoroethers contribution to global warming. The absorption of radiation by greenhouse gases, in particular hydrofluoroethers and hydrofluorocarbons, was investigated using ab initio quantum mechanical methods. Least squares regression techniques were used to create a model based on this data. The placement and number of fluorines in the molecule were found to affect the absorption in the IR window and were incorporated into the model. Several group increment models are discussed. An additive model based on one-carbon groups is found to work satisfactorily in predicting the ab initio calculated vibrational intensities.

  4. Atmospheric aerosols versus greenhouse gases in the twenty-first century.

    PubMed

    Andreae, Meinrat O

    2007-07-15

    Looked at in a simplistic way, aerosols have counteracted the warming effects of greenhouse gases (GHG) over the past century. This has not only provided some 'climate protection', but also prevented the true magnitude of the problem from becoming evident. In particular, it may have resulted in an underestimation of the sensitivity of the climate system to the effect of GHG. Over the present century, the role of aerosols in opposing global warming will wane, as there are powerful policy reasons to reduce their emissions and their atmospheric lifetimes are short in contrast to those of the GHG. On the other hand, aerosols will continue to play a role in regional climate change, especially with regard to the water cycle. The end of significant climate protection by atmospheric aerosols, combined with the potentially very high sensitivity of the climate system, makes sharp and prompt reductions in greenhouse gas emissions, especially CO2, very urgent. PMID:17513271

  5. Quantifying the Summertime Austral Jet Stream and Hadley Cell Response to Stratospheric Ozone and Greenhouse Gases

    NASA Astrophysics Data System (ADS)

    Gerber, E. P.; Son, S.

    2013-12-01

    The impact of anthropogenic forcing on the austral jet stream and Hadley Cell in summer is assessed across three comprehensive climate model datasets, the Chemistry Climate Model Validation Activity 2 (CCMVal2) and Coupled Model Intercomparison Projects, Phases 3 and 5 (CMIP3,5). Changes in stratospheric ozone and greenhouse gases impact the troposphere in this season, and a simple framework based on temperature trends in the lower polar stratosphere and upper tropical troposphere is developed to separate their effects. It suggests that Southern Hemisphere circulation trends are driven by changes in upper troposphere/lower stratosphere temperature gradients: the subtropical and extratropical jets respond similarly when the tropics warm or the polar stratosphere cools. The mean circulation response to greenhouse gases and ozone is fairly comparable across the three multimodel datasets; consistent with previous studies, ozone has dominated changes in recent decades, while in the future, ozone and greenhouse gases will largely offset each other. The multimodel mean perspective, however, masks considerable spread between individual models. Uncertainty resulting from differences in temperature trends is separated from differences in the circulation response to a given temperature change. Both sources of uncertainty contribute equally to model spread. Uncertainty in temperature trends is dominated by differences in the polar stratosphere, not the tropics, suggesting that reducing uncertainty in models' climate sensitivity may not narrow the spread in subtropical and extratropical circulation trends in this season. Rather, the ozone forcing must be constrained. Even if the temperature trends could be perfectly constrained, however, models' 'circulation sensitivity,' differences in the response of the circulation to the same thermal forcing, must be addressed in order to narrow spread in climate projections.

  6. Passive and Active Remote Sensing of Greenhouse Gases in the GOSAT Project

    NASA Astrophysics Data System (ADS)

    Morino, I.; Inoue, M.; Yoshida, Y.; Kikuchi, N.; Yokota, T.; Matsunaga, T.; Uchino, O.; Tanaka, T.; Sakaizawa, D.; Kawakami, S.; Ishii, S.; Mizutani, K.; Shibata, Y.; Abo, M.; Nagasawa, C.

    2014-12-01

    The Greenhouse gases Observing SATellite (GOSAT), launched on 23 Jan. 2009, is the world's first satellite dedicated to measuring concentrations of the two major greenhouse gases, carbon dioxide (CO2) and methane (CH4), from space. Column-averaged dry air mole fractions of CO2 and CH4 (XCO2 and XCH4) are retrieved from the Short-Wavelength InfraRed (SWIR) spectral data observed with the Thermal And Near-infrared Sensor for carbon Observation - Fourier Transform Spectrometer (TANSO-FTS) onboard GOSAT. The present NIES full physics SWIR retrieval algorithm (ver. 02.xx) showed smaller biases and standard deviations (-1.48 ppm and 2.09 ppm for XCO2 and -5.9 ppb and 12.6 ppb for XCH4, respectively) than those of the ver. 01.xx by comparing with data of the Total Carbon Column Observing Network (TCCON). GOSAT retrievals from the GOSAT TANSO-FTS SWIR spectra for more than five years are now ready for scientific research, but may be still influenced by thin aerosols and clouds. Under GOSAT validation activities, we made aircraft observation campaigns to validate the GOSAT products and calibrate TCCON FTSs installed in Japan. In their campaigns, we also made partial column measurements of CO2 with an airborne laser absorption spectrometer, and comparison of ground-based CO2Differential Absorption Lidars with aircraft measurement data. Their active remote sensing experiments are for development of new validation methodology for passive space-based mission and fundamental development for future active space-based mission. The Ministry of the Environment, the Japan Aerospace Exploration Agency, and the National Institute for Environmental Studies also started the development of the follow-on satellite, GOSAT-2 in 2013. GOSAT-2 will be launched in 2017 - 2018. Instruments onboard GOSAT-2 are similar to current GOSAT. The SWIR passive remote sensing of greenhouse gases would be more or less affected by aerosols and thin cirrus clouds. Therefore, active remote sensing is expected

  7. The search for active release of volcanic gases on Mars

    NASA Astrophysics Data System (ADS)

    Khayat, Alain; Villanueva, Geronimo; Mumma, Michael; Tokunaga, Alan

    2015-11-01

    The study of planetary atmospheres by means of spectroscopy is important for understanding their origin and evolution. The presence of short-lived trace gases in the martian atmosphere would imply recent production, for example, by ongoing geologic activity. On Earth, sulfur dioxide (SO2), sulfur monoxide (SO) and hydrogen sulfide (H2S) are the main sulfur-bearing gases released during volcanic outgassing. Carbonyl sulfide (OCS), also released from some volcanoes on Earth (e.g., Erebus and Nyiragongo), could be formed by reactions involving SO2 or H2S inside magma chambers. We carried out the first ground-based, semi-simultaneous, multi-band and multi-species search for such gases above the Tharsis and Syrtis volcanic regions on Mars. The submillimeter search extended between 23 November 2011 and 13 May 2012 which corresponded to Mars’ mid Northern Spring and early Northern Summer seasons (Ls = 34-110°). The strong submillimeter rotational transitions of SO2, SO and H2S were targeted using the high-resolution heterodyne receiver (aka Barney) on the Caltech Submillimeter Observatory. We reached sensitivities sufficient to detect a volcanic release on Mars that is 4% of the SO2 released continuously from Kilauea volcano in Hawaii, or 5% that of the Masaya volcano in Nicaragua. The infrared search covered OCS in its combination band (ν2+ν3) at 3.42 μm at two successive Mars years, during Mars’ late Northern Spring and mid Northern Summer seasons, spanning Ls= 43º and Ls= 147º. The targeted volcanic districts were observed during the two intervals, 14 Dec. 2011 to 6 Jan. 2012 in the first year, and 30 May 2014 to 16 June 2014 in the second year, using the high resolution infrared spectrometer (CSHELL) on NASA’s Infrared Telescope Facility (NASA/IRTF). We will present our results and discuss their implications for current volcanic outgassing activity on the red planet. We gratefully acknowledge support from the NASA Planetary Astronomy Program under NASA

  8. The effect of water oxygen content on the production of greenhouse gases from shallow pond sediments

    NASA Astrophysics Data System (ADS)

    Freer, Adam; Quinton, John; Surridge, Ben; McNamara, Niall

    2014-05-01

    Shallow lakes and ponds, including those commonly found in agricultural landscapes are often only a few metres deep, with surface areas <1ha. Despite this, landscapes may contain a high number of these ponds, amounting to a considerable cumulative surface area. Many of these features, both naturally formed and man-made, receive and trap runoff with high nutrient and sediment loadings. As such, the potential for the production of greenhouse gases (GHGs) through biogeochemical cycling in the pond sediments may be significant. Furthermore, the abundance of available nutrients coupled with the shallow physical characteristics of these systems, mean that short, irregular eutrophic episodes during the summer are common, causing large fluctuations in the oxygen content of the overlying water column. The oxygen content of the water column is often cited as key factor in the production of GHGs in large lake and reservoir systems. Given the limited research focusing on shallow ponds/lakes, and potential for these systems to be important sources of GHGs, the impacts of variable water oxygen content should be investigated. Here we present the results from a sediment microcosm experiment utilising sediment cores from an agricultural pond system in Cumbria, UK. Intact sediment cores were incubated in the dark at in-situ temperature and continuously fed with filtered pond water for 2 weeks. During this time the oxygen content of the water was manipulated between fully oxygenated and anaerobic. Measurements of GHG release were based on calculated dissolved gas concentrations present in the water columns of these cores. Results indicated that during times of water column anoxia, production of methane and carbon dioxide increased significantly, despite the presence of substantial quantities of nitrate in the water columns. No change in N2O production was detected. These results indicate that while representing a significant cumulative carbon store in agricultural landscapes, shallow

  9. The response of soil organic matter decomposition and greenhouse gases emission to global warming and nitrogen addition

    NASA Astrophysics Data System (ADS)

    Oh, H.; Choi, J. H.

    2014-12-01

    The increase of atmospheric greenhouse gases has caused noticeable climate change. The increased temperature by climate change could dramatically change in the decomposition rate and greater losses of carbon from soil organic matter. Decomposition of organic carbon regulates both the amount of organic material which is stored in soils, as well as the amount of mineralized carbon that can be released into the atmosphere as greenhouse gases (CO2 and CH4). In addition, the largest increase in the N-deposition was expected in Asia due to the dramatic increase in anthropogenic activities. Previous results from N-deposition experiments led to apparently contradictory hypotheses regarding the decomposition of organic carbon in soil. N-deposition has been found to decrease the decomposition of chemically complex carbon compounds, while increasing decomposition rates of labile carbon pools. Combined changes in temperature increase and N-deposition have considerable potential to affect soil carbon sequestration/loss and soil nutrient cycling. This study investigated how the combined changes of temperature increase and N-deposition influence mineralization processes and C dynamics of two soil systems (wetlands and forest). For this objective, we conducted a growth chamber experiment to examine the effects of combined changes in temperature increase and N-deposition on the decomposition of organic carbon and emission of greenhouse gases from two different soil systems. The samples were collected in wetland and forest around Gyeongan stream of South Korea. Incubator experiment was conducted under the enhanced air temperature (controlled 20 ℃, 25 ℃ and 30 ℃) and nitrogen addition (low and high condition by using ammonium nitrate). GHGs (CO2, N2O, and CH4) were measured gas chromatograph. Results of experiment show that CO2 flux decrease with time at forest soil and increase at wetland. Moreover high temperature (25 ℃, 30 ℃) and high concentration of nitrogen cause

  10. Massive impact-induced release of carbon and sulfur gases in the early Earth's atmosphere

    NASA Astrophysics Data System (ADS)

    Marchi, S.; Black, B. A.; Elkins-Tanton, L. T.; Bottke, W. F.

    2016-09-01

    Recent revisions to our understanding of the collisional history of the Hadean and early-Archean Earth indicate that large collisions may have been an important geophysical process. In this work we show that the early bombardment flux of large impactors (>100 km) facilitated the atmospheric release of greenhouse gases (particularly CO2) from Earth's mantle. Depending on the timescale for the drawdown of atmospheric CO2, the Earth's surface could have been subject to prolonged clement surface conditions or multiple freeze-thaw cycles. The bombardment also delivered and redistributed to the surface large quantities of sulfur, one of the most important elements for life. The stochastic occurrence of large collisions could provide insights on why the Earth and Venus, considered Earth's twin planet, exhibit radically different atmospheres.

  11. Relative Contribution of Greenhouse Gases and Ozone Change to Temperature Trends in the Stratosphere: A Chemistry/Climate Model Study

    NASA Technical Reports Server (NTRS)

    Stolarski, Richard S.; Douglass, A. R.; Newman, P. A.; Pawson, S.; Schoeberl, M. R.

    2006-01-01

    Long-term changes in greenhouse gases, primarily carbon dioxide, are expected to lead to a warming of the troposphere and a cooling of the stratosphere. We examine the cooling of the stratosphere and compare the contributions greenhouse gases and ozone change for the decades between 1980 and 2000. We use 150 years of simulation done with our coupled chemistry/climate model (GEOS 4 GCM with GSFC CTM chemistry) to calculate temperatures and constituents fiom,1950 through 2100. The contributions of greenhouse gases and ozone to temperature change are separated by a time-series analysis using a linear trend term throughout the period to represent the effects of greenhouse gases and an equivalent effective stratospheric chlorine (EESC) term to represent the effects of ozone change. The temperature changes over the 150 years of the simulation are dominated by the changes in greenhouse gases. Over the relatively short period (approx. 20 years) of ozone decline between 1980 and 2000 changes in ozone are competitive with changes in greenhouse gases. The changes in temperature induced by the ozone change are comparable to, but smaller than, those of greenhouse gases in the upper stratosphere (1-3 hPa) at mid latitudes. The ozone term dominates the temperature change near both poles with a negative temperature change below about 3-5 hPa and a positive change above. At mid latitudes in the upper stratosphere and mesosphere (above about 1 hPa) and in the middle stratosphere (3 to 70 ma), the greenhouse has term dominates. From about 70 hPa down to the tropopause at mid latitudes, cooling due to ozone changes is the largest influence on temperature. Over the 150 years of the simulation, the change in greenhouse gases is the most important contributor to temperature change. Ozone caused a perturbation that is expected to reverse over the coming decades. We show a model simulation of the expected temperature change over the next two decades (2006-2026). The simulation shows a

  12. The state of greenhouse gases in the atmosphere using global observations through 2013

    NASA Astrophysics Data System (ADS)

    Tarasova, Oksana; Koide, Hiroshi; Dlugokencky, Ed; Montzka, Stephen A.; Keeling, Ralph; Tanhua, Toste; Lorenzoni, Laura

    2015-04-01

    We present results from the tenth annual Greenhouse Gas Bulletin (http://www.wmo.int/pages/prog/arep/gaw/ ghg/GHGbulletin.html) of the World Meteorological Organization (WMO). The results are based on research and observations performed by laboratories contributing to the WMO Global Atmosphere Watch (GAW) Programme (www.wmo.int/gaw). The Bulletin presents results of global analyses of observational data collected according to GAW recommended practices and submitted to the World Data Center for Greenhouse Gases (WDCGG), and for the first time, it includes a summary of ocean acidification. Bulletins are prepared by the WMO/GAW Scientific Advisory Group for Greenhouse Gases (http://www.wmo.int/pages/prog/arep/gaw/ScientificAdvisoryGroups.html) in collaboration with WDCGG. The summary of ocean acidification and trends in ocean pCO2 was jointly produced by the International Ocean Carbon Coordination Project (IOCCP) of the Intergovernmental Oceanographic Commission of UNESCO (IOC-UNESCO), the Scientific Committee on Oceanic Research (SCOR), and the Ocean Acidification International Coordination Centre (OA-ICC) of the International Atomic Energy Agency (IAEA). The tenth Bulletin included a special edition published prior to the United Nations Climate Summit in September 2014. The scope of this edition was to demonstrate the level of emission reduction necessary to stabilize radiative forcing by long-lived greenhouse gases. It shows in particular that a reduction in radiative forcing from its current level (2.92 W m-2 in 2013) requires significant reductions in anthropogenic emissions of all major greenhouse gases. Observations used for global analysis are collected at more than 100 marine and terrestrial sites worldwide for CO2 and CH4 and at a smaller number of sites for other greenhouse gases. Globally averaged dry-air mole fractions of carbon dioxide, methane and nitrous oxide derived from this network reached new highs in 2013, with CO2 at 396.0 ± 0.1 ppm, CH4 at

  13. Hydrological sensitivity to greenhouse gases and aerosols in a global climate model

    NASA Astrophysics Data System (ADS)

    KvalevâG, Maria Malene; Samset, BjøRn H.; Myhre, Gunnar

    2013-04-01

    Changes in greenhouse gases and aerosols alter the atmospheric energy budget on different time scales and at different levels in the atmosphere. We study the relationship between global mean precipitation changes, radiative forcing, and surface temperature change since preindustrial times caused by several climate change components (CO2, CH4, sulphate and black carbon (BC) aerosols, and solar forcing) using the National Center for Atmospheric Research Community Earth System Model (CESM1.03). We find a fast response in precipitation due to atmospheric instability that correlates with radiative forcing associated with atmospheric absorption and a slower response caused by changes in surface temperature which correlates with radiative forcing at the top of the atmosphere. In general, global climate models show large differences in climate response to global warming, but here we find a strong relationship between global mean radiative forcing and global mean precipitation changes that is very consistent with other models, indicating that precipitation changes from a particular forcing mechanism are more robust than previously expected. In addition, we look at the precipitation response and relate it to changes in lifetime of atmospheric water vapor (τ). BC aerosols have a significantly larger impact on changes in τ related to surface temperature compared to greenhouse gases, sulphate aerosols, and solar forcing and are the dominating forcing mechanism affecting fast precipitation in this quantity.

  14. Interactive Photochemistry in Earth System Models to Assess Uncertainty in Ozone and Greenhouse Gases. Final report

    SciTech Connect

    Prather, Michael J.; Hsu, Juno; Nicolau, Alex; Veidenbaum, Alex; Smith, Philip Cameron; Bergmann, Dan

    2014-11-07

    Atmospheric chemistry controls the abundances and hence climate forcing of important greenhouse gases including N2O, CH4, HFCs, CFCs, and O3. Attributing climate change to human activities requires, at a minimum, accurate models of the chemistry and circulation of the atmosphere that relate emissions to abundances. This DOE-funded research provided realistic, yet computationally optimized and affordable, photochemical modules to the Community Earth System Model (CESM) that augment the CESM capability to explore the uncertainty in future stratospheric-tropospheric ozone, stratospheric circulation, and thus the lifetimes of chemically controlled greenhouse gases from climate simulations. To this end, we have successfully implemented Fast-J (radiation algorithm determining key chemical photolysis rates) and Linoz v3.0 (linearized photochemistry for interactive O3, N2O, NOy and CH4) packages in LLNL-CESM and for the first time demonstrated how change in O2 photolysis rate within its uncertainty range can significantly impact on the stratospheric climate and ozone abundances. From the UCI side, this proposal also helped LLNL develop a CAM-Superfast Chemistry model that was implemented for the IPCC AR5 and contributed chemical-climate simulations to CMIP5.

  15. Understanding and quantifying greenhouse gases (GHG) emissions: the UK GHG Emissions and Feedback Programme

    NASA Astrophysics Data System (ADS)

    Matthiesen, Stephan; Palmer, Paul; Watson, Andrew; Williams, Mathew

    2016-04-01

    We give an overview over the structure, objectives, and methods of the UK-based Greenhouse Gases Emissions and Feedback Programme. The overarching objective of this research programme is to deliver improved GHG inventories and predictions for the UK, and for the globe at a regional scale. To address this objective, the Programme has developed a comprehensive, multi-year and interlinked measurement and data analysis programme, focussing on the major GHGs carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). The Programme integrates three UK research consortia with complementary objectives, focussing on observation and modelling in the atmosphere, the oceans, and the terrestrial biosphere: GAUGE (Greenhouse gAs Uk and Global Emissions) will produce robust estimates of the UK GHG budget, using new and existing atmospheric measurement networks and modelling activities at a range of scales. It integrates inter-calibrated information from ground-based, airborne, ferry-borne, balloon-borne, and space-borne sensors, including new sensor technology. The GREENHOUSE (Generating Regional Emissions Estimates with a Novel Hierarchy of Observations and Upscaled Simulation Experiments) project aims to understand the spatio-temporal patterns of biogenic GHG emissions in the UK's landscape of managed and semi-managed ecosystems. It uses existing UK field data and several targeted new measurement campaigns to build regional GHG inventories and improve the capabilities of land surface models. RAGNARoCC (Radiatively active gases from the North Atlantic Region and Climate Change) is an oceanographic project to investigate the air-sea fluxes of GHGs in the North Atlantic region. Through dedicated research cruises as well as data collection from ships of opportunity, it develops a comprehensive budget of natural and anthropogenic components of the carbon cycle in the North Atlantic and a better understanding of why the air-sea fluxes of CO2 vary regionally, seasonally and multi

  16. Comment on "Radiative forcings for 28 potential Archean greenhouse gases" by Byrne and Goldblatt (2014)

    NASA Astrophysics Data System (ADS)

    Kochanov, R. V.; Gordon, I. E.; Rothman, L. S.; Sharpe, S. W.; Johnson, T. J.; Sams, R. L.

    2015-08-01

    In the recent article by Byrne and Goldblatt, "Radiative forcing for 28 potential Archean greenhouse gases", Clim. Past. 10, 1779-1801 (2014), the authors employ the HITRAN2012 spectroscopic database to evaluate the radiative forcing of 28 Archean gases. As part of the evaluation of the status of the spectroscopy of these gases in the selected spectral region (50-1800 cm-1), the cross sections generated from the HITRAN line-by-line parameters were compared with those of the PNNL database of experimental cross sections recorded at moderate resolution. The authors claimed that for NO2, HNO3, H2CO, H2O2, HCOOH, C2H4, CH3OH and CH3Br there exist large or sometimes severe disagreements between the databases. In this work we show that for only three of these eight gases a modest discrepancy does exist between the two databases and we explain the origin of the differences. For the other five gases, the disagreements are not nearly at the scale suggested by the authors, while we explain some of the differences that do exist. In summary, the agreement between the HITRAN and PNNL databases is very good, although not perfect. Typically differences do not exceed 10 %, provided that HITRAN data exist for the bands/wavelengths of interest. It appears that a molecule-dependent combination of errors has affected the conclusions of the authors. In at least one case it appears that they did not take the correct file from PNNL (N2O4 (dimer)+ NO2 was used in place of the monomer). Finally, cross sections of HO2 from HITRAN (which do not have a PNNL counterpart) were not calculated correctly in BG, while in the case of HF misleading discussion was presented there based on the confusion by foreign or noise features in the experimental PNNL spectra.

  17. Comment on "Radiative forcings for 28 potential Archean greenhouse gases" by Byrne and Goldblatt (2014)

    DOE PAGESBeta

    Kochanov, R. V.; Gordon, I. E.; Rothman, L. S.; Sharpe, S. W.; Johnson, T. J.; Sams, R. L.

    2015-08-25

    In the recent article by Byrne and Goldblatt, "Radiative forcing for 28 potential Archean greenhouse gases", Clim. Past. 10, 1779–1801 (2014), the authors employ the HITRAN2012 spectroscopic database to evaluate the radiative forcing of 28 Archean gases. As part of the evaluation of the status of the spectroscopy of these gases in the selected spectral region (50–1800 cm-1), the cross sections generated from the HITRAN line-by-line parameters were compared with those of the PNNL database of experimental cross sections recorded at moderate resolution. The authors claimed that for NO2, HNO3, H2CO, H2O2, HCOOH, C2H4, CH3OH and CH3Br there exist largemore » or sometimes severe disagreements between the databases. In this work we show that for only three of these eight gases a modest discrepancy does exist between the two databases and we explain the origin of the differences. For the other five gases, the disagreements are not nearly at the scale suggested by the authors, while we explain some of the differences that do exist. In summary, the agreement between the HITRAN and PNNL databases is very good, although not perfect. Typically differences do not exceed 10 %, provided that HITRAN data exist for the bands/wavelengths of interest. It appears that a molecule-dependent combination of errors has affected the conclusions of the authors. In at least one case it appears that they did not take the correct file from PNNL (N2O4 (dimer)+ NO2 was used in place of the monomer). Finally, cross sections of HO2 from HITRAN (which do not have a PNNL counterpart) were not calculated correctly in BG, while in the case of HF misleading discussion was presented there based on the confusion by foreign or noise features in the experimental PNNL spectra.« less

  18. Influence of biochar amendment on greenhouse gases emission and rice production in paddy field, China

    NASA Astrophysics Data System (ADS)

    Liu, X.; Pan, G. X.; Li, L. Q.; Zhou, T.

    2012-04-01

    Biochar incorporating into agricultural soils as a strategy to increase soil carbon content and mitigate climate change received great attention. We present a field study about biochar amendment into paddy field in Sichuan province 2010, China. The objective was to evaluate the impacts of biochar incorporation on rice production and greenhouse gas emissions. Biochar used in this study was produced from wheat straw at temperature 350-550°C. Biochar incorporated into paddy field before rice transplanting. Methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2) fluxes were measured in situ using closed chamber method during whole rice growing season. Flux of greenhouse gases was monitored at about 7 day's interval. Two rates of N fertilizer (0 and 240 kg N/ha) were applied as urea in combination with 3 biochar rates (0, 20 and 40 t/ha). Amendment of biochar had no influence on rice yield even at the hightest rate of 40 t/ha. However, rice production was greatly relying on chemical N fertilization input. No interact effect was detected between biochar and N fertilizer. Amendment of biochar suppressed N2O emission. During the whole rice growing season, the total N2O emission from chemical fertilizer was reduce by 29% and 53% under biochar amendment rates of 20t/ha and 40t/ha respectively. Total amounts of CO2 and CH4 emitted from paddy fields during whole rice growing season were not greatly increased despite of much carbon brought into soil with biochar. However, biochar amendment slightly increased CO2 emission in the absence of N fertilizer. Our results showed that biochar amendment into paddy field did not increase the global warming potential (GPW) and greenhouse gases emission intensity (GHGI).

  19. Atmospheric greenhouse gases and climate at onset of the last glacial termination

    NASA Astrophysics Data System (ADS)

    Ahn, J.; Brook, E.

    2011-12-01

    Deciphering exact phase relationship between greenhouse gases and climate is important for understanding how greenhouse effect and climate are linked. Especially, onset of the last glacial termination is of great interest because that time interval is important for cracking glacial-interglacial climate cycles. However, previous ice core studies were not able to well handle the issue due to lack of sufficient resolution, precision and/or chronology of greenhouse gas records. Here we present high resolution of CO2 and CH4 records from Siple Dome core, Antarctica. We take advantages from the high accumulation rate in the coring site and high-precision analytical techniques. We also take advantage from the high-resolution of the CH4 records that help better synchronize the CO2 ages with GICC05 Greenland ice core timescale, being consistent with absolute ages obtained from stalagmite records. Implications of our new data for carbon cycles and climate during onset of the last termination will be discussed in the presentation.

  20. [Effects of urea and coated urea on harmful gases concentrations in plastic greenhouse].

    PubMed

    Zhou, Xihong; Zeng, Qingru; Mao, Xiaoyun; Zhang, Litian; Liao, Bohan; Tie, Baiqing; Liao, Zongwen

    2006-09-01

    With simulation test and plastic greenhouse experiment, this paper studied the effects of urea and minerals- coated urea on the soil pH and harmful gases concentrations in plastic greenhouse. The results showed that under simulated condition, the application of these'two N fertilizers led to an initial increase of soil pH, which reached the maximum (an increment of > 50%) within the first week and dropped to the initial level by the end of the fifth week. In plastic greenhouse, applying urea and coated urea resulted in the increase of NH3, NO2 and O3 concentrations. The daily volatilization amount of NH3 and NO2 was higher in urea treatment than in coated urea treatment, and the highest value in urea treatment was 42.36 microg x m(-3) x d(-1) for NH3, 41.95 microg x m(-3) x d(-1) for NO2, and 86.00 microg x m(-3) x d(-1) for O3. The volatilization intensity of NH3 and NO2 was influenced by temperature and sunlight, while the O3 concentration was influenced by sunlight. PMID:17147165

  1. Atmospheric Removal of Very Long-lived Greenhouse Gases in the Mesosphere

    NASA Astrophysics Data System (ADS)

    Totterdill, A.; Kovacs, T.; Gomez Martin, J.; FENG, W.; Chipperfield, M.; Plane, J. M.

    2013-12-01

    Chlorofluorocarbons are known to have serious ozone depleting and global warming potentials. Perfluorinated compounds such as SF6, NF3, SF5CF3 and CF3CF2Cl which have very long lifetimes (ranging from a few centuries to over 3000 years) are too stable to affect stratospheric ozone but do have among the highest per molecule radiative forcing of any greenhouse pollutant, making them extremely potent greenhouse gases. Due to the stability of these gases in the lower atmosphere, mesospheric loss processes could significantly reduce their estimated atmospheric lifetimes and hence, overall climate impact. Potential sinks include reactions with metals and energetic particles such as electrons or short wavelength photons already present in the upper atmosphere. The metals, in this instance iron, sodium or potassium, are produced by meteoric ablation, while background and energetic electrons have the continuous source of photoionization and auroral precipitation, respectively. In this study we investigate the removal potentials of four very long lived gases (SF6, NF3, SF5CF3 and CF3CF2Cl). First, by four metals (Fe, Mg, Na and K), where rate coefficients are measured using the Fast Flow Tube and Pulsed Laser Flash Photolysis / Laser Induced Fluorescence techniques. Second, removal by electron attachment was investigated using a quadrupole mass spectrometer. measurements. Third, Lyman-alpha (121.56 nm) photolysis was measured in a VUV absorption cell. The resulting removal rate coefficients are currently being input into the Whole Atmosphere Community Climate Model (WACCM) to obtain lifetime measurements for these species.

  2. Collaborative Emission Reduction Model Based on Multi-Objective Optimization for Greenhouse Gases and Air Pollutants

    PubMed Central

    Zhang, Yi-min; Wan, Xiao-le; Liu, Yuan-yuan; Wang, Yu-zhi

    2016-01-01

    CO2 emission influences not only global climate change but also international economic and political situations. Thus, reducing the emission of CO2, a major greenhouse gas, has become a major issue in China and around the world as regards preserving the environmental ecology. Energy consumption from coal, oil, and natural gas is primarily responsible for the production of greenhouse gases and air pollutants such as SO2 and NOX, which are the main air pollutants in China. In this study, a mathematical multi-objective optimization method was adopted to analyze the collaborative emission reduction of three kinds of gases on the basis of their common restraints in different ways of energy consumption to develop an economic, clean, and efficient scheme for energy distribution. The first part introduces the background research, the collaborative emission reduction for three kinds of gases, the multi-objective optimization, the main mathematical modeling, and the optimization method. The second part discusses the four mathematical tools utilized in this study, which include the Granger causality test to analyze the causality between air quality and pollutant emission, a function analysis to determine the quantitative relation between energy consumption and pollutant emission, a multi-objective optimization to set up the collaborative optimization model that considers energy consumption, and an optimality condition analysis for the multi-objective optimization model to design the optimal-pole algorithm and obtain an efficient collaborative reduction scheme. In the empirical analysis, the data of pollutant emission and final consumption of energies of Tianjin in 1996–2012 was employed to verify the effectiveness of the model and analyze the efficient solution and the corresponding dominant set. In the last part, several suggestions for collaborative reduction are recommended and the drawn conclusions are stated. PMID:27010658

  3. Collaborative Emission Reduction Model Based on Multi-Objective Optimization for Greenhouse Gases and Air Pollutants.

    PubMed

    Meng, Qing-chun; Rong, Xiao-xia; Zhang, Yi-min; Wan, Xiao-le; Liu, Yuan-yuan; Wang, Yu-zhi

    2016-01-01

    CO2 emission influences not only global climate change but also international economic and political situations. Thus, reducing the emission of CO2, a major greenhouse gas, has become a major issue in China and around the world as regards preserving the environmental ecology. Energy consumption from coal, oil, and natural gas is primarily responsible for the production of greenhouse gases and air pollutants such as SO2 and NOX, which are the main air pollutants in China. In this study, a mathematical multi-objective optimization method was adopted to analyze the collaborative emission reduction of three kinds of gases on the basis of their common restraints in different ways of energy consumption to develop an economic, clean, and efficient scheme for energy distribution. The first part introduces the background research, the collaborative emission reduction for three kinds of gases, the multi-objective optimization, the main mathematical modeling, and the optimization method. The second part discusses the four mathematical tools utilized in this study, which include the Granger causality test to analyze the causality between air quality and pollutant emission, a function analysis to determine the quantitative relation between energy consumption and pollutant emission, a multi-objective optimization to set up the collaborative optimization model that considers energy consumption, and an optimality condition analysis for the multi-objective optimization model to design the optimal-pole algorithm and obtain an efficient collaborative reduction scheme. In the empirical analysis, the data of pollutant emission and final consumption of energies of Tianjin in 1996-2012 was employed to verify the effectiveness of the model and analyze the efficient solution and the corresponding dominant set. In the last part, several suggestions for collaborative reduction are recommended and the drawn conclusions are stated. PMID:27010658

  4. A new model for the Toarcian global climate change: Explosive venting of greenhouse gases from metamorphic aureoles around sill complexes in the Karoo basin

    NASA Astrophysics Data System (ADS)

    Svensen, H.; Planke, S.; Chevallier, L.; Malthe-Sorenssen, A.; Jamtveit, B.; Corfu, F.

    2005-12-01

    Emplacement of voluminous intrusive complexes in organic-rich sedimentary basins may cause global climate change (e.g., intrusive volcanism in the NE Atlantic may have caused the Initial Eocene Thermal Maxima). The Karoo basin in South Africa was intruded by voluminous basaltic melts in the early Jurassic. Black organic-rich shale in the lower parts of the Karoo basin (the Ecca Group) were intruded by up to 130 m thick sub-horizontal magmatic sills, whereas dominantly saucer-shaped sills were emplaced in the overlying fluvial sedimentary sequences. The sills are associated with numerous hydrothermal vent complexes formed in a sub-aerial environment and deep-level breccia pipes. Field relations, borehole data, geochemistry, and geodynamic modeling show that both the deep pipes and the shallow hydrothermal vent complexes were formed as a consequence of pressure build-up in contact aureoles surrounding the sill intrusions. Analyses of shale from the metamorphic aureoles show that most of the organic carbon was lost during the heating event. The formed greenhouse gases (e.g., methane) were explosively released to the atmosphere through the pipes and the vent complexes. Mass balance calculations suggest that the volume of the released greenhouse gases were likely sufficient to initiate the Toarcian greenhouse. The causal relationship between the intrusive event and the Toarcian global warming is corroborated by new U-Pb zircon ages from a dolerite sill associated with breccia pipes in the Ecca Group, both occurring at about 183 Ma.

  5. The Importance of Ecosystem Thresholds in Assessing Safe Concentrations of Greenhouse Gases

    NASA Astrophysics Data System (ADS)

    Janetos, A. C.

    2007-12-01

    There is a major strategic challenge in the public debate about global environmental change related to concentrations of greenhouse gases in the atmosphere that might lead to environmentally, socially, and economically unacceptable impacts. This project takes one approach to this problem: avoiding "dangerous anthropogenic interference" and "allowing ecosystems to adapt." But these phrases implicitly assume that the influences of climate change are likely to be gradual and that there will be substantial time for natural resources to adapt or for managers to cope with change. The current state of the science suggests that something quite different may be in the offing. The Intergovernmental Panel on Climate Change (IPCC) and other assessments of possible impacts now agree on two important points. One is that there is already well-documented evidence of the biological and ecological consequences of climate change - in the behavior of migratory birds, in corals bleached from the influence of warming ocean temperatures, in the loss of glaciers to warming air temperatures, and in the loss of sea grass beds to sea level rise. The second is that ecological systems may not in fact change gradually. Modeling studies and the historical record both suggest that changes in ecosystems can be rapid, large, and sometimes irreversible, i.e., there are thresholds that, once crossed, will present serious coping challenges to humans. Moreover, as suggested in a recent National Academy of Sciences (NAS) workshop on "Understanding and Responding to Multiple Environmental Stresses," dealing with threshold responses that may lead to sudden and dramatic change in societal or environmental structure and function will also require that we develop ways to proceed with decision-making despite the many uncertainties associated with thresholds. These observations present serious challenges to the modeling frameworks used in integrated assessment. Not only do the models have to characterize the

  6. Performance Verification of GOSAT-2 FTS-2 Simulator and Sensitivity Analysis for Greenhouse Gases Retrieval

    NASA Astrophysics Data System (ADS)

    Kamei, A.; Yoshida, Y.; Dupuy, E.; Hiraki, K.; Matsunaga, T.

    2015-12-01

    The GOSAT-2, which is scheduled for launch in early 2018, is the successor mission to the Greenhouse gases Observing Satellite (GOSAT). The FTS-2 onboard the GOSAT-2 is a Fourier transform spectrometer, which has three bands in the near to short-wavelength infrared (SWIR) region and two bands in the thermal infrared (TIR) region to observe infrared light reflected and emitted from the Earth's surface and atmosphere with high-resolution spectra. Column amounts and vertical profiles of major greenhouse gases such as carbon dioxide (CO2) and methane (CH4) are retrieved from acquired radiance spectra. In addition, the FTS-2 has several improvements from the FTS onboard the GOSAT: 1) added spectral coverage in the SWIR region for carbon monoxide (CO) retrieval, 2) increased signal-to-noise ratio (SNR) for all bands, 3) extended range of along-track pointing angles for sunglint observations, 4) intelligent pointing to avoid cloud contamination. Since 2012, we have been developing a software tool, which is called the GOSAT-2 FTS-2 simulator, to simulate spectral radiance data that will be acquired by the GOSAT-2 FTS-2. The objective of it is to analyze/optimize data with respect to the sensor specification, the parameters for Level 1 processing, and the improvement of Level 2 retrieval algorithms. It consists of six components: 1) overall control, 2) sensor carrying platform, 3) spectral radiance calculation, 4) Fourier transform module, 5) Level 1B (L1B) processing, and 6) L1B data output. More realistic and faster simulations have been made possible by the improvement of details about sensor characteristics, the sophistication of data processing and algorithms, the addition of various observation modes, the use of surface and atmospheric ancillary data, and the speed-up and parallelization of radiative transfer code. This simulator is confirmed to be working properly from the reproduction of GOSAT FTS L1B data depends on the ancillary data. We will summarize the

  7. From SO{sub 2} to greenhouse gases: trends and events shaping future emissions trading programs in the United States

    SciTech Connect

    Joseph Kruger

    2005-06-15

    Cap-and-trade programs have become widely accepted for the control of conventional air pollution in the United States. However, there is still no political consensus to use these programs to address greenhouse gases. Meanwhile, in the wake of the success of the US SO{sub 2} and NOx trading programs, private companies, state governments, and the European Union are developing new trading programs or other initiatives that may set precedents for a future national US greenhouse gas trading scheme. This paper summarizes the literature on the 'lessons learned' from the SO{sub 2} trading program for greenhouse gas trading, including lessons about the potential differences in design that may be necessary because of the different sources, science, mitigation options, and economics inherent in greenhouse gases. The paper discusses how the programs and initiatives mentioned above have been shaped by lessons from past trading programs and whether they are making changes to the SO{sub 2} model to address greenhouse gases. It concludes with an assessment of the implications of these initiatives for a future US national greenhouse gas trading program. 91 refs., 2 tabs.

  8. Voluntary reporting of greenhouse gases under Section 1605(b) of the Energy Policy Act of 1992: General Guidelines

    SciTech Connect

    Not Available

    1994-10-01

    Because of concerns with the growing threat of global climate change from increasing emissions of greenhouse gases, Congress authorized a voluntary program for the public to report achievements in reducing those gases. This document offers guidance on recording historic and current greenhouse gas emissions, emissions reductions, and carbon sequestration. Under the Energy Policy Act (EPAct) reporters will have the opportunity to highlight specific achievements. If you have taken actions to lessen the greenhouse gas effect, either by decreasing greenhouse gas emissions or by sequestering carbon, the Department of Energy (DOE) encourages you to report your achievements under this program. The program has two related, but distinct parts. First, the program offers you an opportunity to report your annual emissions of greenhouse gases. Second, the program records your specific projects to reduce greenhouse gas emissions and increase carbon sequestration. Although participants in the program are strongly encouraged to submit reports on both, reports on either annual emissions or emissions reductions and carbon sequestration projects will be accepted. These guidelines and the supporting technical documents outline the rationale for the program and approaches to analyzing emissions and emissions reduction projects. Your annual emissions and emissions reductions achievements will be reported.

  9. Aspects regarding vertical distribution of greenhouse gases resulted from in situ airborne measurements

    NASA Astrophysics Data System (ADS)

    Boscornea, Andreea; Sorin Vajaiac, Nicolae; Ardelean, Magdalena; Benciu, Silviu Stefan

    2016-04-01

    In the last decades the air quality, as well as other components of the environment, has been severely affected by uncontrolled emissions of gases - most known as greenhouse gases (GHG). The main role of GHG is given by the direct influence on the Earth's radiative budget, through Sun light scattering and indirectly by participating in cloud formation. Aldo, many efforts were made for reducing the high levels of these pollutants, e.g., International Panel on Climate Change (IPCC) initiatives, Montreal Protocol, etc., this issue is still open. In this context, this study aims to present several aspects regarding the vertical distribution in the lower atmosphere of some greenhouse gases: water vapours, CO, CO2 and methane. Bucharest and its metropolitan area is one of the most polluted regions of Romania due to high traffic. For assessing the air quality of this area, in situ measurements of water vapours, CO, CO2 and CH4 were performed using a Britten Norman Islander BN2 aircraft equipped with a Picarro gas analyser, model G2401-mc, able to provide precised, continuous and accurate data in real time. This configuration consisting in aircraft and airborne instruments was tested for the first time in Romania. For accomplishing the objectives of the measurement campaign, there were proposed several flight strategies which included vertical and horizontal soundings from 105 m to 3300 m and vice-versa around Clinceni area (20 km West of Bucharest). During 5 days (25.08.2015 - 31.08.2015) were performed 7 flights comprising 10h 18min research flight hours. The measured concentrations of GHS ranged between 0.18 - 2.2 ppm for water vapours with an average maximum value of 1.7 ppm, 0.04 - 0.53 ppm for CO with an average maximum value of 0.21 ppm, 377 - 437.5 ppm for CO2 with an average maximum value of 397 ppm and 1.7 - 6.1 ppm for CH4 with an average maximum value of 2.195 ppm. It was noticed that measured concentrations of GHG are decreasing for high values of sounding

  10. European trends in greenhouse gases emissions from integrated solid waste management.

    PubMed

    Calabrò, Paolo S; Gori, Manuela; Lubello, Claudio

    2015-01-01

    The European Union (EU) has 28 member states, each with very different characteristics (e.g. surface, population density, per capita gross domestic product, per capita municipal solid waste (MSW) production, MSW composition, MSW management options). In this paper several integrated waste management scenarios representative of the European situation have been generated and analysed in order to evaluate possible trends in the net emission of greenhouse gases and in the required landfill volume. The results demonstrate that an integrated system with a high level of separate collection, efficient energy recovery in waste-to-energy plants and very limited landfill disposal is the most effective according to the indices adopted. Moreover, it is evident that a fully integrated system can make MSW management a carbon sink with a potentiality of up to approximately 40 Mt CO2eq year(-1). PMID:25704238

  11. Biomass fuel burning and its implications: deforestation and greenhouse gases emissions in Pakistan.

    PubMed

    Tahir, S N A; Rafique, M; Alaamer, A S

    2010-07-01

    Pakistan is facing problem of deforestation. Pakistan lost 14.7% of its forest habitat between 1990 and 2005 interval. This paper assesses the present forest wood consumption rate by 6000 brick kilns established in the country and its implications in terms of deforestation and emission of greenhouse gases. Information regarding consumption of forest wood by the brick kilns was collected during a manual survey of 180 brick kiln units conducted in eighteen provincial divisions of country. Considering annual emission contributions of three primary GHGs i.e., CO(2), CH(4) and N(2)O, due to burning of forest wood in brick kiln units in Pakistan and using IPCC recommended GWP indices, the combined CO(2)-equivalent has been estimated to be 533019 t y(-1). PMID:20398986

  12. Using STELLA System Dynamic Model to Analyze Greenhouse Gases' Emission From Solid Waste Management in Taiwan

    SciTech Connect

    Horng, Jao-Jia; Lee, R.F.; Liao, K.Y.

    2004-03-31

    Using a system dynamic model (SDM), such as STELLA, to analyze the waste management policy is a new trial for Taiwan's research communities. We have developed an easy and relatively accurate model for analyzing the greenhouse gases emission for the wastes from animal farming and municipalities. With the local research data of the past decade, we extract the most prominent factors and assemble the SDM. The results and scenarios were compared with the national inventory. By comparing to the past data, we found these models reasonably represent the situation in Taiwan. However, SDM can program many scenarios and produce a lot of prediction data. With the development of many program control tools on STELLA, we believe the models could be further used by researchers or policy-makers to find the needed research topics, to set the future scenarios and to determine the management tools.

  13. Global CO2 Distributions over Land from the Greenhouse Gases Observing Satellite (GOSAT)

    NASA Technical Reports Server (NTRS)

    Hammerling, Dorit M.; Michalak, Anna M.; O'Dell, Christopher; Kawa, Randolph S.

    2012-01-01

    January 2009 saw the successful launch of the first space-based mission specifically designed for measuring greenhouse gases, the Japanese Greenhouse gases Observing SATellite (GOSAT). We present global land maps (Level 3 data) of column-averaged CO2 concentrations (X(sub CO2)) derived using observations from the GOSAT ACOS retrieval algorithm, for July through December 2009. The applied geostatistical mapping approach makes it possible to generate maps at high spatial and temporal resolutions that include uncertainty measures and that are derived directly from the Level 2 observations, without invoking an atmospheric transport model or estimates of CO2 uptake and emissions. As such, they are particularly well suited for comparison studies. Results show that the Level 3 maps for July to December 2009 on a lO x 1.250 grid, at six-day resolution capture much of the synoptic scale and regional variability of X(sub CO2), in addition to its overall seasonality. The uncertainty estimates, which reflect local data coverage, X(sub CO2) variability, and retrieval errors, indicate that the Southern latitudes are relatively well-constrained, while the Sahara Desert and the high Northern latitudes are weakly-constrained. A probabilistic comparison to the PCTM/GEOS-5/CASA-GFED model reveals that the most statistically significant discrepancies occur in South America in July and August, and central Asia in September to December. While still preliminary, these results illustrate the usefulness of a high spatiotemporal resolution, data-driven Level 3 data product for direct interpretation and comparison of satellite observations of highly dynamic parameters such as atmospheric CO2.

  14. On Road Study of Colorado Front Range Greenhouse Gases Distribution and Sources

    NASA Astrophysics Data System (ADS)

    Petron, G.; Hirsch, A.; Trainer, M. K.; Karion, A.; Kofler, J.; Sweeney, C.; Andrews, A.; Kolodzey, W.; Miller, B. R.; Miller, L.; Montzka, S. A.; Kitzis, D. R.; Patrick, L.; Frost, G. J.; Ryerson, T. B.; Robers, J. M.; Tans, P.

    2008-12-01

    The Global Monitoring Division and Chemical Sciences Division of the NOAA Earth System Research Laboratory have teamed up over the summer 2008 to experiment with a new measurement strategy to characterize greenhouse gases distribution and sources in the Colorado Front Range. Combining expertise in greenhouse gases measurements and in local to regional scales air quality study intensive campaigns, we have built the 'Hybrid Lab'. A continuous CO2 and CH4 cavity ring down spectroscopic analyzer (Picarro, Inc.), a CO gas-filter correlation instrument (Thermo Environmental, Inc.) and a continuous UV absorption ozone monitor (2B Technologies, Inc., model 202SC) have been installed securely onboard a 2006 Toyota Prius Hybrid vehicle with an inlet bringing in outside air from a few meters above the ground. To better characterize point and distributed sources, air samples were taken with a Portable Flask Package (PFP) for later multiple species analysis in the lab. A GPS unit hooked up to the ozone analyzer and another one installed on the PFP kept track of our location allowing us to map measured concentrations on the driving route using Google Earth. The Hybrid Lab went out for several drives in the vicinity of the NOAA Boulder Atmospheric Observatory (BAO) tall tower located in Erie, CO and covering areas from Boulder, Denver, Longmont, Fort Collins and Greeley. Enhancements in CO2, CO and destruction of ozone mainly reflect emissions from traffic. Methane enhancements however are clearly correlated with nearby point sources (landfill, feedlot, natural gas compressor ...) or with larger scale air masses advected from the NE Colorado, where oil and gas drilling operations are widespread. The multiple species analysis (hydrocarbons, CFCs, HFCs) of the air samples collected along the way bring insightful information about the methane sources at play. We will present results of the analysis and interpretation of the Hybrid Lab Front Range Study and conclude with perspectives

  15. Impact of equatorial and continental airflow on primary greenhouse gases in the northern South China Sea

    NASA Astrophysics Data System (ADS)

    Ou-Yang, Chang-Feng; Yen, Ming-Cheng; Lin, Tang-Huang; Wang, Jia-Lin; Schnell, Russell C.; Lang, Patricia M.; Chantara, Somporn; Lin, Neng-Huei

    2015-06-01

    Four-year ground-level measurements of the two primary greenhouse gases (carbon dioxide (CO2) and methane (CH4)) were conducted at Dongsha Island (DSI), situated in the northern South China Sea (SCS), from March 2010 to February 2014. Their mean mixing ratios are calculated to be 396.3 ± 5.4 ppm and 1863.6 ± 50.5 ppb, with an annual growth rate of +2.19 ± 0.5 ppm yr-1 and +4.70 ± 4.4 ppb yr-1 for CO2 and CH4, respectively, over the study period. Our results suggest that the Asian continental outflow driven by the winter northeast monsoon could have brought air pollutants into the northern SCS, as denoted by significantly elevated levels of 6.5 ppm for CO2 and 59.6 ppb for CH4, which are greater than the marine boundary layer references at Cape Kumukahi (KUM) in the tropical northern Pacific in January. By contrast, the summertime CH4 at DSI is shown to be lower than that at KUM by 19.7 ppb, whereas CO2 is shown to have no differences (<0.42 ppm in July) during the same period. Positive biases of the Greenhouse Gases Observing Satellite (GOSAT) L4B data against the surface measurements are estimated to be 2.4 ± 3.4 ppm for CO2 and 43.2 ± 36.8 ppb for CH4. The satellite products retrieved from the GOSAT showed the effects of anthropogenic emissions and vegetative sinks on land on a vertical profiling basis. The prevailing southeasterly winds originating from as far south as the equator or Southern Hemisphere pass through the lower troposphere in the northern SCS, forming a tunnel of relatively clean air masses as indicated by the low CH4 mixing ratios observed on the DSI in summer.

  16. Comparison of airborne measurements of greenhouse gases over Railroad Valley, Nevada to satellite and model results

    NASA Astrophysics Data System (ADS)

    Tanaka, T.; Yates, E. L.; Iraci, L. T.; Johnson, M. S.; Lopez, J.; Loewenstein, M.; Gore, W.; Tadic, J.; Kuze, A.; Kawakami, S.

    2014-12-01

    As part of the Alpha Jet Atmospheric eXperiment (AJAX) we have measured vertical profiles of greenhouse gases (GHGs) (i.e., carbon dioxide (CO2) and methane (CH4)) over Railroad Valley, NV (RRV) on a monthly basis since 2011. These GHG measurements are conducted to quantify trends of climatically important gases and to validate satellite-based GHG column estimates from Greenhouse Observing Satellite (GOSAT) and Orbiting Carbon Observatory-2 (OCO-2).The vertical profiles of GHGs observed over RRV show relatively uniform features below and above the boundary layer, and mixing ratios are increasing every year. Strong enhancements in the free troposphere are seen in these profiles in some instances. To assess possible sources of these enhancements and their effects on the GHG column average, GHG vertical profiles calculated by the 3-D GEOS-Chem chemical transport model (v9-01-03) and back-trajectory analysis from the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT) are compared with airborne measurements. The main results that we will show are 1) the comparison of vertical GHG distribution calculated from GEOS-Chem and that measured by AJAX, 2) total column GHG values from the model, AJAX, and GOSAT, and 3) demonstrate the source apportionment in GHGs profiles measured at RRV.The RRV playa is a flat high altitude desert site where local sources and sinks of carbon-species are expected to be minimal except for a small oil field. RRV is a radiometrically flat region and has been used to calibrate various satellite radiometers before. These measurements are conducted as part of the Alpha Jet Atmospheric eXperiment (AJAX) which regularly measures GHGs, ozone, and 3-D winds over California and Nevada. The Alpha Jet is operated from NASA Ames Research Center at Moffett Field and airborne instruments are installed in an unpressurized wing pod.

  17. TDL based spectrometer for simultaneously monitoring local and column greenhouse gases

    NASA Astrophysics Data System (ADS)

    Klimchuk, A., Sr.; Semenov, V.

    2015-12-01

    In this paper we present a concept of TDL based spectrometer for local and column greenhouse gases monitoring in particular for CO2, CH4, N2O and O2. The optical scheme of spectrometer's single gas monitoring channel is shown on the figure 1 for CO2 as an example. For each gas monitoring laser radiation is divided into four channels.One of the channels is used for monitoring CO2 abundance in the local atmosphere. This channel is presented by off-axis integrated cavity output spectroscopy (OA ICOS). Mirrors with reflection coefficient R~99.99% are used in order to achieve effective optical path equal to 1500 meters for high precision CO2 monitoring. Measurements will be conducted at a pressure of 100 milibar and a compact diaphragm pump will be used. Reference gas spectra will be used for diode laser frequency stabilization. These spectra will be recorded in specified channel, which is also based on OA ICOS technique. Mirrors reflection coefficients are equal to ~99% in this case. A frequency scale calibration will be provided by Fabry-Perot (FP) ethanol in third channel. The same FP-ethanol will be used for each gas measurements. The last channel is presented by heterodyne spectroscopy and will be used for average column and vertical profiling measurements of greenhouse gases. The intermediate frequency bandwidth is 10 MHz. The spectral coverage is provided by laser wavelength sweep with 100 kHz frequency. Signal registration will be carried out by high-speed electronics without principal nonlinear elements in analog signal path. Present concept incorporates channels for local and column monitoring of CO2 (1.605μ), CH4 (1.65μ), O2 (1.27μ), N2O (2.25μ) and can be easily extended to H2O (1.39μ), CO (2.33μ), etc. measurements.

  18. Observations of greenhouse gases at Sodankylä during 2009-2014

    NASA Astrophysics Data System (ADS)

    Kivi, Rigel; Chen, Huilin; Hatakka, Juha; Heikkinen, Pauli; Laurila, Tuomas

    2015-04-01

    A Fourier Transform Spectrometer (FTS) was installed at the Sodankylä research station in February 2009. The system is recording direct solar spectra in the near-infrared spectral region in the spectral range between 0.7 and 2.5 μm. From the spectra column-averaged abundance of CO2, CH4, N2O and other gases are retrieved. The FTS instrument is based on Bruker 125 HR and participates in the Total Carbon Column Observing Network (TCCON); the instrument has been optimized for greenhouse gas measurements. Here we first present analysis of the reprocessed data set over a six year period from 2009 until 2014. We find statistically significant increase of column amounts of carbon dioxide by 2.4 +/- 0.3 ppm per year and methane increase by 6 +/- 1 ppb per year. In addition to the FTS measurements we have started with year around AirCore measurements at Sodankylä in September 2013. AirCore is an atmospheric sampling system that is directly related to the World Meteorological Organization in situ trace gas measurement scales. AirCore provides profile information of CO2, CH4 and CO from troposphere and lower stratosphere. The AirCore measurements have allowed us to evaluate the accuracy of FTS retrievals. Of special interest has been the quality of the FTS retrievals of CH4 under polar vortex conditions. Finally we present comparisons with space borne measurements by GOSAT (the Greenhouse Gases Observing Satellite) mission. We find a good agreement between the GOSAT and ground based observations. In case of CO2 the relative difference between the two instruments has been -0.03 +/- 0.02 % and in case of CH4 the relative difference has been -0.08 +/- 0.03 %.

  19. Measurements of greenhouse gases at Beromünster tall tower station in Switzerland

    NASA Astrophysics Data System (ADS)

    Berhanu, T. A.; Satar, E.; Schanda, R.; Nyfeler, P.; Moret, H.; Brunner, D.; Oney, B.; Leuenberger, M.

    2015-10-01

    In order to constrain the regional flux of greenhouse gases, an automated measurement system was built on an old radio tower at Beromünster, Switzerland. The measurement system has been running since November 2012 as part of the Swiss greenhouse gases monitoring network (CARBOCOUNT-CH), which is composed of four measurement sites across the country. The Beromünster tall tower has five sampling lines with inlets at 12.5, 44.6, 71.5, 131.6 and 212.5 m a.g.l., and it is equipped with a Picarro CRDS analyzer (G-2401), which continuously measures CO, CO2, CH4 and H2O. Sensors for detection of wind speed and direction, air temperature, barometric pressure, and humidity have also been installed at each height level. We have observed a non-negligible temperature effect in the calibration measurements, which was found to be dependent on the type of cylinder (steel or aluminum) as well as trace gas species (strongest for CO). From a target gas of known mixing ratio that has been measured once a day, we have calculated a long-term reproducibility of 2.79, 0.05 and 0.29 ppb for CO, CO2 and CH4, respectively over 19 months of measurements. The values obtained for CO2 and CH4 are compliant with the WMO recommendations, while the value calculated for CO is higher than the recommendation, which is mainly due to the above mentioned temperature effects.

  20. Measurements of greenhouse gases at Beromünster tall-tower station in Switzerland

    NASA Astrophysics Data System (ADS)

    Ayalneh Berhanu, Tesfaye; Satar, Ece; Schanda, Rudiger; Nyfeler, Peter; Moret, Hanspeter; Brunner, Dominik; Oney, Brian; Leuenberger, Markus

    2016-06-01

    In order to constrain the regional flux of greenhouse gases, an automated measurement system was built on an old radio tower at Beromünster, Switzerland. The measurement system has been running since November 2012 as part of the Swiss greenhouse gases monitoring network (CarboCount-CH), which is composed of four measurement sites across the country. The Beromünster tall tower has five sampling lines with inlets at 12.5, 44.6, 71.5, 131.6, and 212.5 m above ground level, and it is equipped with a Picarro cavity ring-down spectrometer (CRDS) analyzer (G-2401), which continuously measures CO, CO2, CH4, and H2O. Sensors for detection of wind speed and direction, air temperature, barometric pressure, and humidity have also been installed at each height level. We have observed a non-negligible temperature effect in the calibration measurements, which was found to be dependent on the type of cylinder (steel or aluminum) as well as trace gas species (strongest for CO). From a target gas of known mixing ratio that has been measured once a day, we have calculated a long-term reproducibility of 2.79 ppb, 0.05 ppm, and 0.29 ppb for CO, CO2, and CH4, respectively, over 19 months of measurements. The values obtained for CO2 and CH4 are compliant with the WMO recommendations, while the value calculated for CO is higher than the recommendation. Since the installation of an air-conditioning system recently at the measurement cabin, we have acquired better temperature stability of the measurement system, but no significant improvement was observed in the measurement precision inferred from the target gas measurements. Therefore, it seems that the observed higher variation in CO measurements is associated with the instrumental noise, compatible with the precision provided by the manufacturer.

  1. Increased soil emissions of potent greenhouse gases under increased atmospheric CO2

    NASA Astrophysics Data System (ADS)

    van Groenigen, Kees Jan; Osenberg, Craig W.; Hungate, Bruce A.

    2011-07-01

    Increasing concentrations of atmospheric carbon dioxide (CO2) can affect biotic and abiotic conditions in soil, such as microbial activity and water content. In turn, these changes might be expected to alter the production and consumption of the important greenhouse gases nitrous oxide (N2O) and methane (CH4) (refs 2, 3). However, studies on fluxes of N2O and CH4 from soil under increased atmospheric CO2 have not been quantitatively synthesized. Here we show, using meta-analysis, that increased CO2 (ranging from 463 to 780 parts per million by volume) stimulates both N2O emissions from upland soils and CH4 emissions from rice paddies and natural wetlands. Because enhanced greenhouse-gas emissions add to the radiative forcing of terrestrial ecosystems, these emissions are expected to negate at least 16.6 per cent of the climate change mitigation potential previously predicted from an increase in the terrestrial carbon sink under increased atmospheric CO2 concentrations. Our results therefore suggest that the capacity of land ecosystems to slow climate warming has been overestimated.

  2. Comment on "Radiative forcings for 28 potential Archean greenhouse gases" by Byrne and Goldblatt (2014)

    SciTech Connect

    Kochanov, R. V.; Gordon, I. E.; Rothman, L. S.; Sharpe, S. W.; Johnson, T. J.; Sams, R. L.

    2015-08-25

    In the recent article by Byrne and Goldblatt, "Radiative forcing for 28 potential Archean greenhouse gases", Clim. Past. 10, 1779–1801 (2014), the authors employ the HITRAN2012 spectroscopic database to evaluate the radiative forcing of 28 Archean gases. As part of the evaluation of the status of the spectroscopy of these gases in the selected spectral region (50–1800 cm-1), the cross sections generated from the HITRAN line-by-line parameters were compared with those of the PNNL database of experimental cross sections recorded at moderate resolution. The authors claimed that for NO2, HNO3, H2CO, H2O2, HCOOH, C2H4, CH3OH and CH3Br there exist large or sometimes severe disagreements between the databases. In this work we show that for only three of these eight gases a modest discrepancy does exist between the two databases and we explain the origin of the differences. For the other five gases, the disagreements are not nearly at the scale suggested by the authors, while we explain some of the differences that do exist. In summary, the agreement between the HITRAN and PNNL databases is very good, although not perfect. Typically differences do not exceed 10 %, provided that HITRAN data exist for the bands/wavelengths of interest. It appears that a molecule-dependent combination of errors has affected the conclusions of the authors. In at least one case it appears that they did not take the correct file from PNNL (N2O4 (dimer)+ NO2 was used in place of the monomer). Finally, cross sections of HO2 from HITRAN (which do not have a PNNL counterpart) were not calculated correctly in BG, while in the case of HF misleading discussion was presented there based on the confusion by foreign or noise features in the experimental PNNL spectra.

  3. Moisture effects on greenhouse gases generation in nitrifying gas-phase compost biofilters.

    PubMed

    Maia, Guilherme D N; Day, George B; Gates, Richard S; Taraba, Joseph L; Coyne, Mark S

    2012-06-01

    Gas-phase compost biofilters are extensively used in concentrated animal feeding operations to remove odors and, in some cases, ammonia from air sources. The expected biochemical pathway for these predominantly aerobic systems is nitrification. However, non-uniform media with low oxygen levels can shift biofilter microbial pathways to denitrification, a source of greenhouse gases. Several factors contribute to the formation of anoxic/anaerobic zones: media aging, media and particle structure, air velocity distribution, compaction, biofilm thickness, and moisture content (MC) distribution. The present work studies the effects of media moisture conditions on ammonia (NH(3)) removal and greenhouse gas generation (nitrous oxide, N(2)O and methane, CH(4)) for gas-phase compost biofilters subject to a 100-day controlled drying process. Continuous recordings were made for the three gases and water vapor (2.21-h sampling cycle, each cycle consisted of three gas species, and water vapor, for a total of 10,050 data points). Media moisture conditions were classified into three corresponding media drying rate (DR) stages: Constant DR (wetter media), falling DR, and stable-dry system. The first-half of the constant DR period (0-750 h; MC=65-52%, w.b.) facilitated high NH(3) removal rates, but higher N(2)O generation and no CH(4) generation. At the drier stages of the constant DR (750-950 h; MC=52-48%, w.b.) NH(3) removal remained high but N(2)O net generation decreased to near zero. In the falling DR stage (1200-1480 h; MC=44-13%) N(2)O generation decreased, CH(4) increased, and NH(3) was no longer removed. No ammonia removal or greenhouse gas generation was observed in the stable-dry system (1500-2500 h; MC=13%). These results indicate that media should remain toward the drier region of the constant DR (in close proximity to the falling DR stage; MC=50%, approx.), to maintain high levels of NH(3) removal, reduced levels of N(2)O generation, and nullify levels of CH(4

  4. Greenhouse gases measurements in road tunnel in São Paulo Megacity, Brazil

    NASA Astrophysics Data System (ADS)

    Fornaro, A.; Andrade, M. F.; Ynoue, R. Y.; Galichio, W.; Astolfo, R.; Miranda, R. M.

    2012-04-01

    The Metropolitan Area of São Paulo (MASP) is the richest area in Brazil and is one of the largest megacities in the world, with more than 20 million inhabitants. The fleet, with more than 7 million vehicles, is unique in that most are fueled by ethanol or by a gasoline-ethanol (flex-fuel vehicles) mixture containing 75-78% gasoline (by volume) and 22-25% ethanol (a blend referred to as gasohol). Nowadays, approximately 50% of the fuel burned by the fleet is ethanol. The vehicular emissions are responsible for approximately 98, 97, and 96%, respectively, of all emissions of carbon monoxide (CO), hydrocarbons (HCs) and nitrogen oxides (NOx). In addition, the fleet is the largest source of CO2 emissions in the MASP. The goal is to evaluate of the vehicles emissions of the pollutants and greenhouse gases (CH4 and CO2) in the MASP. The gases carbon dioxide and methane were carried out by Picarro G2301 Analyzer for CO2/CH4/H2O in air. Field measurements were carried out in two road tunnels within the MASP: May 2 to 13, 2011 in the Janio Quadros (JQ) tunnel and from July 04 to 19, 2011 in the Rodoanel (RA) tunnel. The JQ tunnel is located in the southwest portion of São Paulo. It is a two-lane tunnel that is 1900 m in length, and the traffic in both lanes flows in the same directions. The in-tunnel emissions are mainly from gasohol- and ethanol-powered vehicles. The RA tunnel is located in the West portion of the city and different from JQ tunnel. It is 1700m in length and carries gasohol, ethanol and diesel powered vehicles, being that approximately 40% of the heavy-duty (burning diesel) in its four-lane. The results showed that the effects of the number and velocity of the vehicles in the variability of greenhouse gases and pollutants. The carbon dioxide reaching the hourly maximum value of 550 ppm in-inside the JQ tunnel, and 900 ppm in-side the RA tunnel.

  5. Evaluation of photo-acoustic infrared multigas analyzer in measuring concentrations of greenhouse gases emitted from feedlot soil/manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Photo-acoustic infrared multigas analyzers (PIMAs) are being increasingly utilized to measure concentrations and fluxes of greenhouse gases (i.e., N2O, CO2, and CH4) at the soil surface because of their low cost, portability, and ease of operation. This research evaluated a PIMA in combination with ...

  6. Greenhouse Gases Emission from Land Application of Swine Waste Water: A Comparison of Three Different Swine Slurry Application Methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Agricultural activities (including land application of animal manures) account for about 20% of the total human induced global warming budget due to emissions of greenhouse gases (GHG). Recently, there has been an increasing emphasis on controlling these emissions from livestock operations. One of...

  7. Use of U.S. Croplands for Biofuels Increases Greenhouse Gases Through Emissions from Land-Use Change

    NASA Astrophysics Data System (ADS)

    Searchinger, Timothy; Heimlich, Ralph; Houghton, R. A.; Dong, Fengxia; Elobeid, Amani; Fabiosa, Jacinto; Tokgoz, Simla; Hayes, Dermot; Yu, Tun-Hsiang

    2008-02-01

    Most prior studies have found that substituting biofuels for gasoline will reduce greenhouse gases because biofuels sequester carbon through the growth of the feedstock. These analyses have failed to count the carbon emissions that occur as farmers worldwide respond to higher prices and convert forest and grassland to new cropland to replace the grain (or cropland) diverted to biofuels. By using a worldwide agricultural model to estimate emissions from land-use change, we found that corn-based ethanol, instead of producing a 20% savings, nearly doubles greenhouse emissions over 30 years and increases greenhouse gases for 167 years. Biofuels from switchgrass, if grown on U.S. corn lands, increase emissions by 50%. This result raises concerns about large biofuel mandates and highlights the value of using waste products.

  8. Nature of the gases released from lunar rocks and soils upon crushing

    NASA Technical Reports Server (NTRS)

    Gibson, E. K., Jr.; Andrawes, F. F.

    1978-01-01

    Qualitative and quantitative analyses of inorganic gases released from lunar basalts, breccias and soils by crushing have been performed in an apparatus which consists of a piston operating in a stream of purified He and a dual-column gas chromatograph equipped with He-ionization detectors. The apparatus eliminates the problem of adsorption of the released gases by fresh sample surfaces generated by crushing. Upper concentration levels for nitrogen, H2, CH4, O2 and other gases released from crushed basalts are reported. A direct correlation is established between the amount of nitrogen released from lunar soils by crushing and the lunar soil maturity indicator proposed by Morris (1976).

  9. Miniaturized Laser Heterodyne Radiometer (LHR) for Measurements of Greenhouse Gases in the Atmospheric Column

    NASA Technical Reports Server (NTRS)

    Steel, Emily; McLinden, Matthew

    2012-01-01

    This passive laser heterodyne radiometer (LHR) instrument simultaneously measures multiple trace gases in the atmospheric column including carbon dioxide (CO2) and methane (CH4), and resolves their concentrations at different altitudes. This instrument has been designed to operate in tandem with the passive aerosol sensor currently used in AERONET (an established network of more than 450 ground aerosol monitoring instruments worldwide). Because aerosols induce a radiative effect that influences terrestrial carbon exchange, simultaneous detection of aerosols with these key carbon cycle gases offers a uniquely comprehensive measurement approach. Laser heterodyne radiometry is a technique for detecting weak signals that was adapted from radio receiver technology. In a radio receiver, a weak input signal from a radio antenna is mixed with a stronger local oscillator signal. The mixed signal (beat note, or intermediate frequency) has a frequency equal to the difference between the input signal and the local oscillator. The intermediate frequency is amplified and sent to a detector that extracts the audio from the signal. In the LHR instrument described here, sunlight that has undergone absorption by the trace gas is mixed with laser light at a frequency matched to a trace gas absorption feature in the infrared (IR). Mixing results in a beat signal in the RF (radio frequency) region that can be related to the atmospheric concentration. For a one-second integration, the estimated column sensitivities are 0.1 ppmv for CO2, and <1 ppbv for CH4. In addition to producing a standalone ground measurement product, this instrument could be used to calibrate/validate four Earth observing missions: ASCENDS (Active Sensing of CO2 Emissions over Nights, Days, and Seasons), OCO-2 (Orbiting Carbon Observatory), OCO-3, and GOSAT (Greenhouse gases Observational SATellite). The only network that currently measures CO2 and CH4 in the atmospheric column is TCCON (Total Carbon Column

  10. Air pollution, greenhouse gases and climate change: Global and regional perspectives

    NASA Astrophysics Data System (ADS)

    Ramanathan, V.; Feng, Y.

    Greenhouse gases (GHGs) warm the surface and the atmosphere with significant implications for rainfall, retreat of glaciers and sea ice, sea level, among other factors. About 30 years ago, it was recognized that the increase in tropospheric ozone from air pollution (NO x, CO and others) is an important greenhouse forcing term. In addition, the recognition of chlorofluorocarbons (CFCs) on stratospheric ozone and its climate effects linked chemistry and climate strongly. 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 air pollution is transported across continents and ocean basins due to fast long-range transport, 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 may nucleate more cloud droplets, which makes the clouds reflect more solar radiation. The dimming has a surface cooling effect and decreases evaporation of moisture from the surface, thus slows down the hydrological cycle. On the other hand, absorption of solar radiation by black carbon and some organics increase atmospheric heating and tend to amplify greenhouse warming of the atmosphere. ABCs are concentrated in regional and mega-city hot spots. Long-range transport from these hot spots causes widespread plumes over the adjacent oceans. Such a pattern of regionally concentrated surface dimming and atmospheric solar heating, accompanied by widespread 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. In S. Asia and N. Africa, the large north-south gradient in the ABC

  11. Spatial mapping of greenhouse gases using laser absorption spectrometers at local scales of interest

    NASA Astrophysics Data System (ADS)

    Dobler, Jeremy; Zaccheo, T. S.; Blume, Nathan; Braun, Michael; Botos, Chris; Pernini, Timothy G.

    2015-10-01

    Over the past two years a new system capable of measuring the 2-D spatial distribution of atmospheric CO2 over areas on the order of 1 km2 and time scales of a few minutes, has been developed and demonstrated. The Greenhouse gas Laser Imaging Tomography Experiment (GreenLITE) - developed under a cooperative agreement with the National Energy Technology Laboratory (NETL) of the U.S. Department of Energy (DOE) - attempts to improve monitoring capabilities of Ground Carbon Storage (GCS) sites. GreenLITE sensors are based on an intensity modulated continuous wave (IM-CW) approach developed at ITT (now part of Harris Corp.) in 2004. The GreenLITE system recently completed a remote deployment of nearly 4,000 hours at a GCS site in Illinois. It provided continuous, real-time spatial distribution maps of CO2 via an open web-based interface from February to August 2015. In early 2015 we began work on a new implementation of GreenLITE capable of providing similar measurements over a 25 km2 area and are planning to test the system over a 5 km range late summer 2015. If successful the system will be deployed in an urban environment late 2015, demonstrating the utility of real-time 2-D spatial mapping of CO2 concentrations at this scale. This paper will review the concept for this new measurement capability, including results from the 1 km system. Ultimately, the measurement concept can be adapted to other greenhouse gases such as CH4 and NO2.

  12. Methane and Other Greenhouse Gases in the Arctic - Measurements, Process Studies and Modelling (MAMM)

    NASA Astrophysics Data System (ADS)

    Pyle, J. A.; Warwick, N. J.; Cain, M.; Hayman, G.; Skiba, U.; Drewer, J.; Dinsmore, K.; George, C.; Nisbet, E. G.; Lowry, D.; Fisher, R. E.; France, J. L.; Lanoiselle, M.; Brownlow, R. B.; Allen, G.; Bower, K.; Gallagher, M. W.; Percival, C.; Illingworth, S. M.; Jones, B.; Muller, J.; O'Shea, S.; Manning, A. C.; Kozlova, E.; Manning, A. J.; Smith, M.; Anderson, D.; Bauguitte, S.

    2013-12-01

    The Arctic is a major source of atmospheric methane and other greenhouse gases, of both natural and anthropogenic origin. Arctic greenhouse gas sources need to be quantified, by strength, geographic location, character (e.g. wetlands, gas fields, hydrates), and by temporal variation (daily, seasonally and annually), and their vulnerability to change assessed. To this end, the MAMM project was commissioned as part of the UK NERC Arctic Research Programme. It involves an integrated series of measurement and modelling activities. Analysis of atmospheric gas concentrations, isotopic character, and source fluxes, are being made from both the ground and from the NERC FAAM (Facility for Airborne Atmospheric Measurements) aircraft. The measurements (historic and new) are being interpreted using a suite of models (trajectory, forward and inverse) to improve the understanding of the local/regional scale, placing the role of Arctic emissions in the context of large-scale global atmospheric change. The first measurement campaign was held in August 2012. Surface flux measurements were made at the Sodankylä research station in Finland, together with in-situ surface and aircraft measurements over a wider area. In addition to flights over the Sodankylä wetlands, the aircraft also flew out to Svalbard, Norway to investigate marine sources of methane. Further campaigns are taking place in Sweden in August and September 2013. The initial measurements have been used to infer wetland emission fluxes and confirm that Scandinavian wetlands are a major source of methane in this region (see posters by Fisher et al, O'Shea et al). The aircraft also measured a high-methane plume over the sea between mainland Norway and Svalbard, which was likely advected from mainland wetland sources (see poster by France et al). Results from the field campaigns will be presented, alongside results from the NAME model (the UK Met Office's Numerical Atmospheric dispersion Modelling Environment) to help

  13. Wood decomposition in Amazonian hydropower reservoirs: An additional source of greenhouse gases

    NASA Astrophysics Data System (ADS)

    Abril, Gwenaël; Parize, Marcelo; Pérez, Marcela A. P.; Filizola, Naziano

    2013-07-01

    Amazonian hydroelectric reservoirs produce abundant carbon dioxide and methane from large quantities of flooded biomass that decompose anaerobically underwater. Emissions are extreme the first years after impounding and progressively decrease with time. To date, only water-to-air fluxes have been considered in these estimates. Here, we investigate in two Amazonian reservoirs (Balbina and Petit Saut) the fate of above water standing dead trees, by combining a qualitative analysis of wood state and density through time and a quantitative analysis of the biomass initially flooded. Dead wood was much more decomposed in the Balbina reservoir 23 years after flooding than in the Petit Saut reservoir 10 years after flooding. Termites apparently played a major role in wood decomposition, occurring mainly above water, and resulting in a complete conversion of this carbon biomass into CO2 and CH4 at a timescale much shorter than reservoir operation. The analysis of pre-impounding wood biomass reveals that above-water decomposition in Amazonian reservoirs is a large, previously unrecognized source of carbon emissions to the atmosphere, representing 26-45% of the total reservoir flux integrated over 100 years. Accounting for both below- and above-water fluxes, we could estimate that each km2 of Amazonian forest converted to reservoir would emit over 140 Gg CO2-eq in 100 years. Hydropower plants in the Amazon should thus generate 0.25-0.4 MW h per km2 flooded area to produce lower greenhouse gas emissions than gas power plants. They also have the disadvantage to emit most of their greenhouse gases the earliest years of operation.

  14. Emissions of Greenhouse Gases from Urban Xi'an, China - Direct Measurements by Eddy Covariance

    NASA Astrophysics Data System (ADS)

    VanReken, T. M.; Mwaniki, G. R.; VanderSchelden, G.; O'Keeffe, P.; Waldo, S.; Erickson, M. H.; Lamb, B. K.; Jobson, B. T.; Tie, X.; Cao, J.

    2012-12-01

    Throughout the world and especially in Asia, rapid urbanization is resulting in an increasing number of very large cities. In these areas, the rate of development can outpace the perceived need for environmental regulation, and frequently there are inadequate resources available to monitor pollution or enforce compliance with those environmental regulations that do exist. These limitations obviously impact air quality on a local scale, but cities also have significant environmental impacts on regional and even global scales. In order to understand and mitigate these impacts on the surrounding environment, it is first necessary to robustly characterize the pollutant emissions themselves. This can be a significant challenge. Major discrepancies arise when comparing emissions inventories based on bottom-up compilations of source types, number, and activity levels to estimates inferred from satellite observations and other large-scale techniques. Direct measurements of neighborhood-scale emission fluxes via micrometeorological approaches provide a means to resolve these differences. Such measurements can be used to quantify the integrated vertical exchange for a wide variety of greenhouse gases and other pollutants, typically with spatial footprints of tens of square kilometers and with temporal resolutions of ~30 minutes. Here we present the results of an urban flux study conducted in Xi'an, China in August 2011. For the study a 23 m tower was erected atop the ~100 m tall administration building at Xi'an Jiaotong University. From the tower, we employed an eddy covariance approach to measure concentrations and fluxes of carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and carbon monoxide (CO). Here we present an analysis of the air-surface exchange of these gases. Results indicate that while our study site in Xi'an was a net source of these species, the greenhouse gas fluxes were significantly smaller than at other sites around the world and exhibited a

  15. Emission Inventory of Halogenated greenhouse gases in China during 1980-2050

    NASA Astrophysics Data System (ADS)

    Fang, X.; Velders, G. J. M.; Ravishankara, A. R.; Molina, M.; Su, S.; Zhang, J.; Zhou, X.; Hu, J.; Prinn, R. G.

    2015-12-01

    China is currently the largest producer and consumer of ozone-depleting substances (ODSs) which are regulated by the Montreal Protocol (MP). Many ODSs are also powerful greenhouse gases (GHGs). The Multilateral Fund has subsidized ~1 billion US dollars for the ODS phase out in China, and thus the return on this investment is of great interest. This study gives a comprehensive emission inventory in China from 1980 to 2013 of halocarbons including ODSs and their alternatives, the hydrofluorocarbons (HFCs) that are also greenhouse gases. We then project these emissions up to 2050 according to the MP and several policy options. Total emissions of ODS and HFCs were estimated to be ~500 CO2-eq Tg/yr in 2013 which are equivalent to ~5% of total GHG emissions in China including fossil fuel CO2 emissions. Our estimate shows that China has succeeded in substantially reducing CFC-11-equivalent emissions (to protect the ozone layer), and CO2-equivalent emissions (to protect climate) of ODSs since the mid-1990s when their phase out started in China in compliance with the MP. Furthermore, the avoided CO2-eq emissions due to compliance with the MP are even greater compared to the reduced emissions, for example net cumulative avoided emissions during 19 year period between 1995-2013 are comparable to the current one year CO2 emissions from fossil fuels in China. We find that HFC CO2-eq emissions increased rapidly in last decade, which make up ~2% in 2005 to ~20% of total halocarbon CO2-eq emissions in 2013. Under a baseline scenario in which HFCs are used as alternatives in the ongoing phase out of HCFCs in China, emissions of HFCs are predicted to be important components of both China's and global future GHG emissions. However, potential exists for minimizing China's HFC emissions under mitigation scenarios. Our conclusions about China's past and future ODS and HFC emission trajectories are likely to apply to other developing countries, with important implications for mitigating

  16. Experiments on thermal release of implanted noble gases from minerals and their implications for noble gases in lunar soil grains

    NASA Astrophysics Data System (ADS)

    Futagami, T.; Ozima, M.; Nagai, S.; Aoki, Y.

    1993-07-01

    Experiments on ion implantation were performed in order to study the release mechanisms of solar particles from lunar soil grains. Helium, neon, and argon ions were implanted into olivine and ilmenite. The release temperatures of noble gases were investigated by heating samples stepwise; the results show that they depend on irradiation energy and dose. We conclude that the release temperature is related to the size of bubbles in which noble gases are trapped: noble gases in small and large bubbles are released at 400-600 C and 800-1200 C, respectively. In Ne and Ar implantation experiments into olivine, a component was released during recrystallization of amorphized surfaces. Based on these experimental results, we suggest that components released from lunar ilmenite grains at different temperatures would correspond to solar particles of different energies. We also suggest that He and Ne of solar wind energy (about 1 keV/amu) should be retained in lunar ilmenite grains, while they should be lost from olivine grains.

  17. Airborne observations of greenhouse gases in the North Slope of Alaska during summer 2015

    NASA Astrophysics Data System (ADS)

    Biraud, S.; Torn, M. S.; Sweeney, C.; Springston, S. R.; Sedlacek, A. J., III

    2015-12-01

    Atmospheric temperatures are warming faster in the Arctic than predicted by climate models. The impact of this warming on permafrost degradation is not well understood, but it is projected to increase carbon decomposition and greenhouse gas production (CO2 and/or CH4) by arctic ecosystems. Airborne observations of atmospheric trace gases, aerosols and cloud properties in North Slopes of Alaska (NSA) are improving our understanding of global climate, with the goal of reducing the uncertainty in global and regional climate simulations and projections. From June 1 through September 15, 2015, the Atmospheric radiation measurement (ARM) airborne facility (AAF) deployed a G1 research aircraft (ARM-ACME-V mission) to fly over the North Slope of Alaska, with occasional vertical profiling to measure trace gas concentrations, between Prudhoe Bay, Oliktok point, Barrow, Atqasuk, Ivotuk, and Toolik Lake. The aircraft payload includes a Picarro and a LGR analyzers for continuous measurements of CO2, CH4, H2O, and CO and N2O mixing ratios, and a 12-flask sampler for analysis of carbon cycle gases (CO2, CO, CH4, N2O, 13CO2, 14CO2, carbonyl sulfide, and trace hydrocarbon species including ethane). The aircraft payload also include measurements of aerosol properties (number size distribution, total number concentration, absorption, and scattering), cloud properties (droplet and ice size information), atmospheric thermodynamic state, and solar/infrared radiation. Preliminary results using CO2, CH4, CO, ethane, and soot spectroscopy observations are used to tease apart biogenic and thermogenic (biomass burning, and oil and gas production) contributions

  18. Investigating high concentrations of three greenhouse gases in the Los Angeles Basin and San Bernardino Valley

    NASA Astrophysics Data System (ADS)

    Kirpes, R.; Blake, D. R.; Marrero, J.

    2013-12-01

    Following the Montreal Protocol of 1987 calling for the phase-out of CFCs and other ozone depleting substances, HCFCs and HFCs were introduced as alternatives despite still being greenhouse gases with high global warming potentials. In this study, whole air samples were collected during four research flights over Southern California aboard the NASA DC-8 Airborne Science Laboratory as part of the NASA Student Airborne Science Program. These samples were then analyzed by gas chromatography using a suite of detectors for many compounds, including HFC-134a, HCFC-22, and HFC-152a. HCFC-22 is primarily used as a refrigerant, while HFC-134a and HFC-152a are also used as aerosol propellants and foam blowing agents. High concentrations of these three compounds were observed for samples taken at low altitudes over urban areas around Los Angeles and San Bernardino. Exceptionally high concentrations were seen for all three compounds in samples taken near the Ontario and San Bernardino airports. Concentrations of HFC-134a, HCFC-22, and HFC-152a were enhanced above background levels near other airports sampled in the Los Angeles Basin and San Bernardino Valley. It is clear that concentrations of these three gases are higher in the San Bernardino Valley than in the Los Angeles Basin, and locations with exceptionally high concentrations were investigated to identify potential point sources. Concentrations of these three compounds were also compared to data from past SARP missions and data collected at Trinidad Head, California since 2005 as part of the AGAGE network. Comparison of the average values for each of these campaigns reveal that the background concentrations of HFC-134a, HCFC-22, and HFC-152a are all increasing with a strong linear trend in Southern California.

  19. Air Surface Temperature Correlation with Greenhouse Gases by Using Airs Data Over Peninsular Malaysia

    NASA Astrophysics Data System (ADS)

    Rajab, Jasim Mohammed; MatJafri, M. Z.; Lim, H. S.

    2014-08-01

    The main objective of this study is to develop algorithms for calculating the air surface temperature (AST). This study also aims to analyze and investigate the effects of greenhouse gases (GHGs) on the AST value in Peninsular Malaysia. Multiple linear regression is used to achieve the objectives of the study. Peninsular Malaysia has been selected as the research area because it is among the regions of tropical Southeast Asia with the greatest humidity, pockets of heavy pollution, rapid economic growth, and industrialization. The predicted AST was highly correlated ( R = 0.783) with GHGs for the 6-year data (2003-2008). Comparisons of five stations in 2009 showed close agreement between the predicted AST and the observed AST from AIRS, especially in the wet season (within 1.3 K). The in situ data ranged from 1 to 2 K. Validation results showed that AST ( R = 0.776-0.878) has values nearly the same as the observed AST from AIRS. We found that O3 during the wet season was indicated by a strongly positive beta coefficient (0.264-0.992) with AST. The CO2 yields a reasonable relationship with temperature with low to moderate beta coefficient (-0.065 to 0.238). The O3, CO2, and environmental variables experienced different seasonal fluctuations that depend on weather conditions and topography. The concentration of gases and pollution were the highest over industrial zones and overcrowded cities, and the dry season was more polluted compared with the wet season. These results indicate the advantage of using the satellite AIRS data and a correlation analysis to investigate the effect of atmospheric GHGs on AST over Peninsular Malaysia. An algorithm that is capable of retrieving Peninsular Malaysian AST in all weather conditions with total uncertainties ranging from 1 to 2 K was developed.

  20. A new method for estimating greenhouse gases and ammonia emissions from livestock buildings

    NASA Astrophysics Data System (ADS)

    Barrancos, José; Briz, Susana; Nolasco, Dácil; Melián, Gladys; Padilla, Germán; Padrón, Eleazar; Fernández, Isabel; Pérez, Nemesio; Hernández, Pedro A.

    2013-08-01

    It is widely known that carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) are the main greenhouse gases contributing to global climate change. Emission factors for the aforementioned gases have been proposed in order to calculate the contribution of livestock farming to global climate change. However, these emission factors depend on many additional factors such as the housing system, environmental conditions, etc., which implies some uncertainties in their estimation. Therefore, works that aim at improving experimental calculation of these emissions are crucial to provide reliable estimates of the emissions produced by livestock. The purpose of this work was to apply a new methodology inspired by the accumulation chamber method to estimate emission rates from livestock buildings. The work was based on measuring the increase of gas emissions inside the livestock building by means of the remote sensing technique Open-Path FTIR (OP-FTIR). Previously to the measurements, livestock building cattle was confined outside of the building. Utilization of fan ventilation system favoured the homogenization of air inside the building. This experiment proved that evolution of CH4 and CO2 concentrations inside the livestock building behaved like an accumulation chamber unlike the N2O which did not show such behaviour. Results showed CH4, CO2 and NH3 emissions of 167 ± 54,700 ± 200 and 1.3 ± 0.2 kg head-1 year-1, respectively. One of the main parameters affecting the estimated emission factors is the type of animal feeding. Therefore, it is essential to investigate the influence of food composition on CH4 and CO2 emission in a relative larger number of operating cattle buildings since the methodology herein proposed is an easy and cheap tool to study livestock emission factors and their variability.

  1. Greenhouse Gases and Gas-Water-Rock Interactions at the Surface of Early Mars

    NASA Astrophysics Data System (ADS)

    Murphy, W. M.; Bass, D. S.

    1998-09-01

    Consideration of multiphase equilibria is required to make realistic speculations of conditions on early Mars and can provide indications of modern exploration targets to aid characterization of that remote environment. Greenhouse gases are proposed to sustain elevated surface temperatures compatible with geomorphologic evidence for the stability of liquid water on early Mars. CO2 is commonly invoked as a greenhouse gas at pressures up to 5 bars or more, e.g., [1]. However, solid-gas equilibria show that CO2 pressure is limited by formation of CO2 ice in the upper atmosphere for surface pressure of 2 bars [2]. Recently, SO2 at 10-7 bar in a 2 bar CO2 atmosphere (0.1 ppmv SO2) has been postulated to augment warming in the upper atmosphere on early Mars [3], which could inhibit CO2 precipitation. However, oxidation of SO2 would produce sulfuric acid which dissolves in liquid water and attacks rock components, producing metal sulfate solutions and precipitating gypsum (CaSO4-2H2O). Occurrence of gypsum in SNC meteorites demonstrates conditions permitting oxidation of SO2 on Mars [4]. Equilibrium aqueous speciation calculations show that at low O2 pressure, 10-11 bar of SO2 (i.e., 4 orders of magnitude less than proposed) at equilibrium with water generates sulfuric acid of pH 0.5. Reaction path calculations indicate that silicate minerals would dissolve rapidly in this solution with precipitation of a silica phase, clay minerals, and gypsum. Precipitation of gypsum would deplete atmospheric SO2. These multiphase interactions demonstrate that greenhouse stabilization of liquid water due to an SO2 pressure of 10-7 bar is incompatible with a realistic water-rock system. In the absence of elevated concentrations of atmospheric SO2, at elevated CO2 pressure, and at near neutral pH, geochemical equilibrium models predict that the mineral nahcolite (NaHCO3) may precipitate as a consequence of gas-water-rock interactions. If observed, this mineral could be used together with

  2. Elastic and plastic soil deformation and its influence on emission of greenhouse gases

    NASA Astrophysics Data System (ADS)

    Haas, Christoph; Holthusen, Dörthe; Mordhorst, Anneka; Lipiec, Jerzy; Horn, Rainer

    2016-04-01

    Soil management alters physical, chemical and biological soil properties. Stress application affects microbiological activity and habitats for microorganisms in the root zone and causes soil degradation. We hypothesized that stress application results in altered greenhouse gas emissions if soil strength is exceeded. In the experiments, soil management dependent greenhouse gas emissions of intact soil cores (no, reduced, conventional tillages) were determined using two experimental setups; CO2 emissions were determined with: a dynamic measurement system, and a static chamber method before and after a vertical soil stress had been applied. For the latter CH4 and N2O emissions were analyzed additionally. Stress dependent effects can be summed as follows: In the elastic deformation range microbiological activity increased in conventional tillage soil and decreased in reduced tillage and no tillage. Beyond the precompression stress a release of formerly protected soil organic carbon and an almost total loss of CH4 oxidizability occurred. Only swelling and shrinkage of no tillage and reduced tillage regenerated their microhabitat function. Thus, the direct link between soil strength and microbial activity can be applied as a marker for soil rigidity and the transition to new disequilibria concerning microbial activity and composition.

  3. Evaluation of different techniques to control hydrogen sulfide and greenhouse gases from animal production systems

    NASA Astrophysics Data System (ADS)

    Gautam, Dhan Prasad

    The livestock manure management sector is one of the prime sources for the emission of greenhouse gases (GHGs) and other pollutant gases such as ammonia (NH3) and hydrogen sulfide (H2S), which may affect the human health, animal welfare, and the environment. So, worldwide investigations are going on to mitigate these gaseous emissions. The overall objective of this research was to investigate different approaches (dietary manipulation and nanotechnology) for mitigating the gaseous emissions from livestock manure system. A field study was conducted to investigate the effect of different levels of dietary proteins (12 and 16%) and fat levels (3 to 5.5%) fed to beef cattle on gaseous emission (methane-CH4, nitrous oxide-N2O, carbon dioxide-CO 2 and hydrogen sulfide-H2S) from the pen surface. To evaluate the effects of different nanoparticles (zinc oxide-nZnO; and zirconium-nZrO 2) on these gaseous emissions from livestock manure stored under anaerobic conditions, laboratory studies were conducted with different treatments (control, bare NPs, NPs entrapped alginate beads applying freely and keeping in bags, and used NPs entrapped alginate beads). Field studies showed no significant differences in the GHG and H2S emissions from the manure pen surface. Between nZnO and nZrO2, nZnO outperformed the nZrO2 in terms of gases production and concentration reduction from both swine and dairy liquid manure. Application of nZnO at a rate of 3 g L-1 showed up to 82, 78, 40 and 99% reduction on total gas production, CH 4, CO2 and H2S concentrations, respectively. The effectiveness of nZnO entrapped alginate (alginate-nZnO) beads was statistically lower than the bare nZnO, but both of them were very effective in reducing gas production and concentrations. These gaseous reductions were likely due to combination of microbial inhibition of microorganisms and chemical conversion during the treatment, which was confirmed by microbial plate count, SEM-EDS, and XPS analysis. However

  4. Long open path Fourier transform spectroscopy measurements of greenhouse gases in the near infrared

    NASA Astrophysics Data System (ADS)

    Griffith, David; Pöhler, Denis; Schmidt, Stefan; Hammer, Samuel; Vardag, Sanam; Levin, Ingeborg; Platt, Ulrich

    2015-04-01

    Atmospheric composition measurements are an important tool to quantify local and regional emissions and sinks of greenhouse gases. But how representative are in situ measurements at one point in an inhomogeneous environment? Open path Fourier Transform Spectroscopy (FTS) measurements potentially offer spatial averaging and continuous measurements of several trace gases (including CO2, CH4, CO and N2O) simultaneously in the same airmass. Spatial averaging over kilometre scales is a better fit to the finest scale atmospheric models becoming available, and helps bridge the gap between models and in situ measurements. With what precision, accuracy and reliability can such measurements be made? Building on our pooled experience in ground-level open path Fourier transform spectroscopy and TCCON solar FTS in the infrared (Wollongong) and long path DOAS techniques in the UV-visible (Heidelberg), we set up a new type of open path measurement system across a 1.5 km one-way path in urban Heidelberg, Germany, using FTS in the near infrared. Direct open-atmosphere measurements of trace gases CO2, CH4, CO and N2O as well as O2 were retrieved from several absorption bands between 4000 and 8000 cm-1 (2.5 - 1.25 micron). At one end of the path an in situ FTIR analyser simultaneously collected well calibrated measurements of the same species for comparison with the open path-integrated measurements. The measurements ran continuously from June - November 2014. We introduce the open path FTS measurement system and present an analysis of the results, including assessment of precision, accuracy relative to co-incident in situ measurements, reliability, and avenues for further improvements and extensions. Short term precision of the open path measurement of CO2 was better than 1 ppm for 5 minute averages and thus sufficient for studies in urban and other non-background environments. Measurement bias relative to calibrated in situ measurements was stable across the measurement period. The

  5. Atmospheric observations for quantifying emissions of point-source synthetic greenhouse gases (CF4, NF3 and HFC-23)

    NASA Astrophysics Data System (ADS)

    Arnold, Tim; Manning, Alistair J.; Li, Shanlan; Kim, Jooil; Park, Sunyoung; Fraser, Paul J.; Mitrevski, Blagoj; Steele, L. Paul; Krummel, Paul B.; Mühle, Jens; Weiss, Ray F.

    2016-04-01

    The fluorinated species carbon tetrafluoride (CF4; PFC-14), nitrogen trifluoride (NF3) and trifluoromethane (CHF3; HFC-23) are potent greenhouse gases with 100-year global warming potentials of 6,630, 16,100 and 12,400, respectively. Unlike the majority of CFC-replacement compounds that are emitted from fugitive and mobile emission sources, these gases are largely emitted from large single point sources - semiconductor manufacturing facilities (all three), aluminium smelting plants (CF4) and chlorodifluoromethane factories (HFC-23). In this work we show the potential for atmospheric measurements to understand regional sources of these gases and to highlight emission 'hotspots'. We target our analysis on measurements from two Advanced Global Atmospheric Gases Experiment (AGAGE) long term monitoring sites that are particularly sensitive to regional emissions of these gases: Gosan on Jeju Island in the Republic of Korea and Cape Grim on Tasmania in Australia. These sites measure CF4, NF3 and HFC-23 alongside a suite of greenhouse and stratospheric ozone depleting gases every two hours using automated in situ gas-chromatography mass-spectrometry instrumentation. We couple each measurement to an analysis of air history using the regional atmospheric transport model NAME (Numerical Atmospheric dispersion Modelling Environment) driven by 3D meteorology from the Met Office's Unified Model, and use a Bayesian inverse method (InTEM - Inversion Technique for Emission Modelling) to calculate yearly emission changes over a decade (2005-2015) at high spatial resolution. At present these gases make a small contribution to global radiative forcing, however, given that their impact could rise significantly and that point sources of such gases can be mitigated, atmospheric monitoring could be an important tool for aiding emissions reduction policy.

  6. Counteracting the climate effects of volcanic eruptions using short-lived greenhouse gases

    NASA Astrophysics Data System (ADS)

    Samset, B. H.; Fuglestvedt, J.; Shine, K. P.

    2014-12-01

    A large volcanic eruption might constitute a climate emergency, significantly altering global temperature and precipitation for several years. Major future eruptions will occur, but their size or timing cannot be predicted. How could global society prepare for, and react to, such emergencies? One possibility is deliberate, coordinated emissions of short-lived greenhouse gases, along a pathway designed to match the climate responses to the eruption. We estimate such an emission pathway, countering a hypothetical eruption three times the size of Mt Pinatubo in 1991. Using a global climate model to evaluate global and regional responses to the eruption, with and without counter emissions, we show that it may be possible to counteract its climate effects, significantly dampening the abrupt impact of the eruption. We then raise practical, financial and ethical aspects related to such a strategy. Designed emissions to counter temporary global cooling would not have the disadvantages associated with more commonly discussed geoengineering to avoid long-term warming. Nevertheless, implementation would still face significant challenges.

  7. Influence of nuclear power unit on decreasing emissions of greenhouse gases

    NASA Astrophysics Data System (ADS)

    Stanek, Wojciech; Szargut, Jan; Kolenda, Zygmunt; Czarnowska, Lucyna

    2015-03-01

    The paper presents a comparison of selected power technologies from the point of view of emissions of greenhouse gases. Such evaluation is most often based only on analysis of direct emissions from combustion. However, the direct analysis does not show full picture of the problem as significant emissions of GHG appear also in the process of mining and transportation of fuel. It is demonstrated in the paper that comparison of power technologies from the GHG point of view has to be done using the cumulative calculus covering the whole cycle of fuel mining, processing, transportation and end-use. From this point of view coal technologies are in comparable level as gas technologies while nuclear power units are characterised with lowest GHG emissions. Mentioned technologies are compared from the point of view of GHG emissions in full cycle. Specific GHG cumulative emission factors per unit of generated electricity are determined. These factors have been applied to simulation of the influence of introduction of nuclear power units on decrease of GHG emissions in domestic scale. Within the presented simulations the prognosis of domestic power sector development according to the Polish energy policy till 2030 has been taken into account. The profitability of introduction of nuclear power units from the point of view of decreasing GHG emissions has been proved.

  8. EVN, a regional energy supplier -- measures for reduction of greenhouse gases

    SciTech Connect

    Hans-Georg, R.

    1996-12-31

    The growing demand for electricity, natural gas and heat is facing efforts to lower the emissions of greenhouse gases. Generating electricity and heat measures to maximize efficiency are effective and significant. Accordingly, a modernizing project will be presented. As a part of the project the district heat supply also reduces the emissions of CO{sub 2}. The increasing supply with natural gas in the state of Lower Austria has a positive environmental effect. Natural gas produces less specific CO{sub 2} emissions than do liquid or solid fuels. EVN`s total CO{sub 2} balance is arrived at by adding together CO{sub 2} reduction attributable to the use of natural gas and heat and CO{sub 2} emissions from the power stations. Over the last years the share of CO{sub 2} in the total emission account dropped. A number of different measures shall be added and will be described, like using alternative forms of energy for instance solar energy, biomass, water power and one of the main items are the energy consulting services free of charge and EVN`s modern tariffs, which also help conserve electrical energy.

  9. Collection, transfer and transport of waste: accounting of greenhouse gases and global warming contribution.

    PubMed

    Eisted, Rasmus; Larsen, Anna W; Christensen, Thomas H

    2009-11-01

    The collection, transfer and transport of waste are basic activities of waste management systems all over the world. These activities all use energy and fuels, primarily of fossil origin. Electricity and fuel consumptions of the individual processes were reviewed and greenhouse gases (GHG) emissions were quantified. The emission factors were assigned a global warming potential (GWP) and aggregated into global warming factors (GWFs), which express the potential contribution to global warming from collection, transport and transfer of 1 tonne of wet waste. Six examples involving collection, transfer and transport of waste were assessed in terms of GHG emissions, including both provision and use of energy. (GHG emissions related to production, maintenance and disposal of vehicles, equipment, infrastructure and buildings were excluded.) The estimated GWFs varied from 9.4 to 368 kg CO(2)-equivalent (kg CO(2)-eq.) per tonne of waste, depending on method of collection, capacity and choice of transport equipment, and travel distances. The GHG emissions can be reduced primarily by avoiding transport of waste in private cars and by optimization of long distance transport, for example, considering transport by rail and waterways. PMID:19808734

  10. Greenhouse gases emissions from waste management practices using Life Cycle Inventory model.

    PubMed

    Chen, Tsao-Chou; Lin, Cheng-Fang

    2008-06-30

    When exploring the correlation between municipal solid waste management and green house gas emission, the volume and physical composition of the waste matter must be taken into account. Due to differences in local environments and lifestyles the quantity and composition of waste often vary. This leads to differences in waste treatment methods and causes different volumes of greenhouse gases (GHGs), highlighting the need for local research. In this study the Life Cycle Inventory method was used with global warming indicator GHGs as the variables. By quantifying the data and adopting a region-based approach, this created a model of household MSWM in Taipei City, a metropolitan region in Taiwan. To allow analysis and comparison a compensatory system was then added to expand the system boundary. The results of the analysis indicated that out of all the solid waste management sub-models for a function unit, recycling was the most effective method for reducing GHG emissions while using kitchen food waste as swine feeding resulted in the most GHG emissions. As for the impact of waste collection vehicles on emissions, if the efficiency of transportation could be improved and energy consumption reduced, this will help solid waste management to achieve its goal of reducing GHG emissions. PMID:18164811

  11. POTENTIAL OF GREENHOUSE GASES REDUCTION BY FUEL CROP CULTIVATION UTILIZING SEWAGE SLUDGE IN JAPAN

    NASA Astrophysics Data System (ADS)

    Honda, Ryo; Fukushi, Kensuke

    Potential of greenhouse gases (GHG) reduction was estimated and compared in six scenarios of fuel crop cultivation by utilizing sewage sludge in Japan. Bioethanol from corn and biodiesel fuel from soybean was selected as biofuel produced. When all the sludge discharged from sewage treatment plants in 18 major cities was utilized for soybean cultivation and subsequent biodiesel fuel production, produced biofuel corresponded to 4.0% of GHG emitted from sewage treatment in Japan. On the other hand, cultivation area for fuel crop cultivation was found to be the regulating factor. When fuel crop was cultivated only in abandoned agricultural fields, produced biofuel corresponded to 0.60% and 0.62%, respectively, in the case that corn and soybean was cultivated. Production of biodiesel fuel from soybean was estimated to have more net reduction potential than bioehanol production from corn when sludge production is limited, because required sewage sludge compost was 2.5-times larger in corn although reduction potential per crop area was 2-times larger in bioethanol production from corn.

  12. Emissions of greenhouse gases and air pollutants from commercial aircraft at international airports in Korea

    NASA Astrophysics Data System (ADS)

    Song, Sang-Keun; Shon, Zang-Ho

    2012-12-01

    The emissions of greenhouse gases (GHGs) and air pollutants from aircraft in the boundary layer at four major international airports in Korea over a two-year period (2009-2010) were estimated using the Emissions and Dispersion Modeling System (EDMS) (i.e. activity-based (Landing/Take-Off (LTO) cycle) methodology). Both domestic and international LTOs and ground support equipment at the airports were considered. The average annual emissions of GHGs (CO2, N2O, CH4 and H2O) at all four airports during the study period were 1.11 × 103, 1.76 × 10-2, -1.85 × 10-3 and 3.84 × 108 kt yr-1, respectively. The emissions of air pollutants (NOx, CO, VOCs and particulate matter) were 5.20, 4.12, 7.46 × 10-1 and 3.37 × 10-2 kt yr-1, respectively. The negative CH4 emission indicates the consumption of atmospheric CH4 in the engine. The monthly and daily emissions of GHGs and air pollutants showed no significant variations at all airports examined. The emissions of GHGs and air pollutants for each aircraft operational mode differed considerably, with the largest emission observed in taxi-out mode.

  13. Effect of the greenhouse gases (CO2, H2O, SO2) on Martian paleoclimate

    NASA Technical Reports Server (NTRS)

    Postawko, S. E.; Kuhn, W. R.

    1986-01-01

    There is general agreement that certain surface features on Mars are indicative of the presence of liquid water at various times in the geologic past. In particular, the valley networks are difficult to explain by a mechanism other than the flow of liquid water. It has been suggested in several studies that a thick CO2 atmosphere on Mars early in its history could have provided a greenhouse warming that would have allowed the flow of water either on the surface or just below the surface. However, this effect was examined with a detailed radiation model, and it was found that if reduced solar luminosity early in the history of the solar system is taken into account, even three bars of CO2 will not provide sufficient greeenhouse warming. The addition of water vapor and sulflur dioxide (both plausible gases that may have been emitted by Martian volcanoes) to the atmosphere also fail to warm the surface above 273 K for reduced solar luminosity conditions. The increase in temperature may be large enough, however, for the formation of these features by brines.

  14. Hydrological sensitivity and global temperature change to greenhouse gases and aerosols in CESM

    NASA Astrophysics Data System (ADS)

    Kvalevag, M. M.; Samset, B. H.; Myhre, G.

    2012-04-01

    We present a set of climate model experiments using the NCAR Community Earth System Model (CESM1.03) to investigate the relationship between precipitation changes and surface temperature change for several forcing mechanisms. The model simulations include forcing mechanisms since preindustrial times causing either warming or cooling, in order to study the energy budget at different levels (surface, atmosphere and top of atmosphere), temperature changes and precipitation change. On a short timescale the precipitation changes are due to atmospheric instability and reduced convection caused by the presence of a forcing mechanism in the atmosphere. On longer timescale it is the adjusted surface temperatures that drive the changes. In particular we look at the precipitation response from black carbon and study the model sensitivity to absorbing aerosols by introducing black carbon at different altitudes in the model. Our results are similar to earlier studies regarding greenhouse gases and sulphate aerosols, but extend previous results on black carbon aerosols. We introduce BC aerosols in different altitudes and look at how sensitive the precipitation changes are due to the placement of a warming forcing agent in the atmosphere. We find that while the surface temperature response of a column of BC is positive, it is composed of a warming component at low altitudes and a cooling component at higher altitudes. The precipitation response of a change in BC concentration is however always negative.

  15. The impact of greenhouse gases on past changes in tropospheric ozone

    NASA Astrophysics Data System (ADS)

    Lang, C.; Waugh, D. W.; Olsen, M. A.; Douglass, A. R.; Liang, Q.; Nielsen, J. E.; Oman, L. D.; Pawson, S.; Stolarski, R. S.

    2012-12-01

    The impact of changes in the abundance of greenhouse gases (GHGs) on the evolution of tropospheric ozone (O3) between 1960 and 2005 is examined using a version of the Goddard Earth Observing System chemistry-climate model (GEOS CCM) with a combined troposphere-stratosphere chemical mechanism. Simulations are performed to isolate the relative role of increases in methane (CH4) and stratospheric ozone depleting substances (ODSs) on tropospheric O3. The 1960 to 2005 increases in GHGs (CO2, N2O, CH4, and ODSs) cause increases of around 1-8% in zonal-mean tropospheric O3 in the tropics and northern extratropics, but decreases of 2-4% in most of the southern extratropics. These O3 changes are due primarily to increases in CH4 and ODSs, which cause changes of comparable magnitude but opposite sign. The CH4-related increases in O3are similar in each hemisphere (˜6%), but the ODS-related decreases in the southern extratropics are much larger than in northern extratropics (10% compared to 2%). This results in an interhemispheric difference in the sign of past O3 change. Increases in the other GHGs (CO2 and N2O) and SSTs have only a small impact on the total burden over this period, but do cause zonal variations in the sign of changes in tropical O3 that are coupled to changes in vertical velocities and water vapor.

  16. Advances in data processing for open-path Fourier transform infrared spectrometry of greenhouse gases.

    PubMed

    Shao, Limin; Griffiths, Peter R; Leytem, April B

    2010-10-01

    The automated quantification of three greenhouse gases, ammonia, methane, and nitrous oxide, in the vicinity of a large dairy farm by open-path Fourier transform infrared (OP/FT-IR) spectrometry at intervals of 5 min is demonstrated. Spectral pretreatment, including the automated detection and correction of the effect of interrupting the infrared beam, is by a moving object, and the automated correction for the nonlinear detector response is applied to the measured interferograms. Two ways of obtaining quantitative data from OP/FT-IR data are described. The first, which is installed in a recently acquired commercial OP/FT-IR spectrometer, is based on classical least-squares (CLS) regression, and the second is based on partial least-squares (PLS) regression. It is shown that CLS regression only gives accurate results if the absorption features of the analytes are located in very short spectral intervals where lines due to atmospheric water vapor are absent or very weak; of the three analytes examined, only ammonia fell into this category. On the other hand, PLS regression works allowed what appeared to be accurate results to be obtained for all three analytes. PMID:20879801

  17. Regional rainfall decline in Australia attributed to anthropogenic greenhouse gases and ozone levels

    NASA Astrophysics Data System (ADS)

    Delworth, Thomas L.; Zeng, Fanrong

    2014-08-01

    Precipitation in austral autumn and winter has declined over parts of southern and especially southwestern Australia in the past few decades. According to observations and climate models, at least part of this decline is associated with changes in large-scale atmospheric circulation, including a poleward movement of the westerly winds and increasing atmospheric surface pressure over parts of southern Australia. Here we use a high-resolution global climate model to analyse the causes of this rainfall decline. In our simulations, many aspects of the observed regional rainfall decline over southern and southwest Australia are reproduced in response to anthropogenic changes in levels of greenhouse gases and ozone in the atmosphere, whereas anthropogenic aerosols do not contribute to the simulated precipitation decline. Simulations of future climate with this model suggest amplified winter drying over most parts of southern Australia in the coming decades in response to a high-end scenario of changes in radiative forcing. The drying is most pronounced over southwest Australia, with total reductions in austral autumn and winter precipitation of approximately 40% by the late twenty-first century.

  18. Are Greenhouse Gases Changing ENSO Precursors in the Western North Pacific?

    SciTech Connect

    Wang, S-Y; Heureux, Michelle L.; Yoon, Jin-Ho

    2013-09-01

    Using multiple observational and modeling datasets, we document a strengthening relationship between boreal winter sea surface temperature anomalies (SSTA) in the western North Pacific (WNP) and the development of the El Nino-Southern Oscillation (ENSO) one year later. The increased WNP-ENSO association emerged in the mid 20th century and has grown through the present, reaching correlation coefficients as high as ~0.70 in recent decades. Fully coupled climate experiments with the Community Earth System Model (CESM) replicate the WNP-ENSO association and indicate that greenhouse gases (GHG) are largely responsible for the observed increase. We speculate that shifts in the location and amplitudes of positive SST trends in the subtropical-tropical western Pacific impacts the low-level circulation so that WNP variability is increasingly influencing the development of ENSO one year later. A strengthened GHG-driven relationship between the WNP and ENSO provides an example of how anthropogenic climate change can potentially improve the skill of intraseasonal-to-interannual climate prediction.

  19. Emissions of greenhouse gases from the use of transportation fuels and electricity

    SciTech Connect

    DeLuchi, M.A. )

    1991-11-01

    This report presents estimates of full fuel-cycle emissions of greenhouse gases from using transportation fuels and electricity. The data cover emissions of carbon dioxide (CO{sub 2}), methane, carbon monoxide, nitrous oxide, nitrogen oxides, and nonmethane organic compounds resulting from the end use of fuels, compression or liquefaction of gaseous transportation fuels, fuel distribution, fuel production, feedstock transport, feedstock recovery, manufacture of motor vehicles, maintenance of transportation systems, manufacture of materials used in major energy facilities, and changes in land use that result from using biomass-derived fuels. The results for electricity use are in grams of CO{sub 2}-equivalent emissions per kilowatt-hour of electricity delivered to end users and cover generating plants powered by coal, oil, natural gas, methanol, biomass, and nuclear energy. The transportation analysis compares CO{sub 2}-equivalent emissions, in grams per mile, from base-case gasoline and diesel fuel cycles with emissions from these alternative- fuel cycles: methanol from coal, natural gas, or wood; compressed or liquefied natural gas; synthetic natural gas from wood; ethanol from corn or wood; liquefied petroleum gas from oil or natural gas; hydrogen from nuclear or solar power; electricity from coal, uranium, oil, natural gas, biomass, or solar energy, used in battery-powered electric vehicles; and hydrogen and methanol used in fuel-cell vehicles.

  20. Emissions of greenhouse gases from the use of transportation fuels and electricity. Volume 1, Main text

    SciTech Connect

    DeLuchi, M.A.

    1991-11-01

    This report presents estimates of full fuel-cycle emissions of greenhouse gases from using transportation fuels and electricity. The data cover emissions of carbon dioxide (CO{sub 2}), methane, carbon monoxide, nitrous oxide, nitrogen oxides, and nonmethane organic compounds resulting from the end use of fuels, compression or liquefaction of gaseous transportation fuels, fuel distribution, fuel production, feedstock transport, feedstock recovery, manufacture of motor vehicles, maintenance of transportation systems, manufacture of materials used in major energy facilities, and changes in land use that result from using biomass-derived fuels. The results for electricity use are in grams of CO{sub 2}-equivalent emissions per kilowatt-hour of electricity delivered to end users and cover generating plants powered by coal, oil, natural gas, methanol, biomass, and nuclear energy. The transportation analysis compares CO{sub 2}-equivalent emissions, in grams per mile, from base-case gasoline and diesel fuel cycles with emissions from these alternative- fuel cycles: methanol from coal, natural gas, or wood; compressed or liquefied natural gas; synthetic natural gas from wood; ethanol from corn or wood; liquefied petroleum gas from oil or natural gas; hydrogen from nuclear or solar power; electricity from coal, uranium, oil, natural gas, biomass, or solar energy, used in battery-powered electric vehicles; and hydrogen and methanol used in fuel-cell vehicles.

  1. Global warming: Experimental study about the effect of accumulation of greenhouse gases in the atmosphere

    NASA Astrophysics Data System (ADS)

    Molto, Carlos; Mas, Miquel

    2010-05-01

    The project presented here was developed by fifteen year old students of the Institut Sabadell (Sabadell Secondary School. Spain). The objective of this project was to raise the students awareness' about the problem of climate change, mainly caused by the accumulation of greenhouse gases in the atmosphere. It is also intended that students use the scientific method as an effective system of troubleshooting and that they use the ICTs (Information and Communication Technologies) to elicit data and process information. To develop this project, four lessons of sixty minutes each were needed. The first lesson sets out the role of the atmosphere as an Earth's temperature regulator, highlighting the importance of keeping the levels of carbon dioxide, methane and water steam in balance. The second lesson is focused on the experimental activity that students will develop in the following lesson. In lesson two, students will present and justify their hypothesis about the experiment. Some theoretical concepts, necessary to carry out the experiment, will also be explained. The third lesson involves the core of the project, that is the experiment in the laboratory. The experiment consists on performing the atmosphere heating on a little scale. Four different atmospheres are created inside four plastic boxes heated by an infrared lamp. Students work in groups (one group for each atmosphere) and have to monitor the evolution of temperature by means of a temperature sensor (Multilog software). The first group has to observe the relationship between temperature and carbon dioxide levels increase, mainly caused by the widespread practice of burning fossil fuels by growing human populations. The task of this group is to measure simultaneously the temperature of an empty box (without CO2) and the temperature of a box with high carbon dioxide concentration. The carbon dioxide concentration is the result of the chemical reaction when sodium carbonate mixes with hydrochloric acid. The

  2. Frontiers of QC Laser spectroscopy for high precision isotope ratio analysis of greenhouse gases

    NASA Astrophysics Data System (ADS)

    Emmenegger, Lukas; Mohn, Joachim; Harris, Eliza; Eyer, Simon; Ibraim, Erkan; Tuzson, Béla

    2016-04-01

    An important milestone for laser spectroscopy was achieved when isotope ratios of greenhouse gases were reported at precision levels that allow addressing research questions in environmental sciences. Real-time data with high temporal resolution at moderate cost and instrument size make the optical approach highly attractive, complementary to the well-established isotope-ratio mass-spectrometry (IRMS) method. Especially appealing, in comparison to IRMS, is the inherent specificity to structural isomers having the same molecular mass. Direct absorption in the MIR in single or dual QCL configuration has proven highly reliable for the sta-ble isotopes of CO2, N2O and CH4. The longest time series of real-time measurements is currently available for δ13C and δ18O in CO2 at the high-alpine station Jung-fraujoch. At this well-equipped site, QCL based direct absorption spectroscopy (QCLAS) measurements are ongoing since 2008 1,2. Applications of QCLAS for N2O and CH4 stable isotopes are considerably more challenging because of the lower atmospheric mixing ratios, especially for the less abundant species, such as N218O and CH3D. For high precision (< 0.1 ‰) measurements in ambient air, QCLAS may be combined with a fully automated preconcentration unit yielding an up to 500 times concentration increase and the capability to separate the target gas from spectral interferants by se-quential desorption 3. Here, we review our recent developments on high precision isotope ratio analysis of greenhouse gases, with special focus on the isotopic species of N2O and CH4. Furthermore, we show environ-mental applications illustrating the highly valuable information that isotope ratios of atmospheric trace gases can carry. For example, the intramolecular distribution of 15N in N2O gives important information on the geochemical cycle of N2O4-6, while the analysis of δ13C and δ D in CH4 may be applied to disentangle microbial, fossil and landfill sources 7. 1 Sturm, P., Tuzson, B

  3. Path-radiance correction by polarization observation of Sun glint glitter for remote measurements of tropospheric greenhouse gases.

    PubMed

    Aoki, Tadao; Aoki, Teruo; Fukabori, Masashi

    2002-08-20

    High-accuracy remote measurement of greenhouse gases is hampered by contamination of the field of view by the path radiance of solar radiation scattered from clouds and aerosols. A method is proposed for eliminating the effect of path radiance by differentiating two components of polarized light. The polarization of path radiance is measured directly at the wave-number region of strong water-vapor absorption. Using this measurement, we eliminate the components of path radiance involved in other bands, which are used for greenhouse gas measurements, by differentiating two components of the polarized light. It is shown that the effect of path radiance on retrieving the column amount of gases potentially can be reduced to below 0.1%. PMID:12206201

  4. Fluxes of greenhouse gases at two different aquaculture ponds in the coastal zone of southeastern China

    NASA Astrophysics Data System (ADS)

    Yang, Ping; He, Qinghua; Huang, Jiafang; Tong, Chuan

    2015-08-01

    Shallow water ponds are important contributors to greenhouse gas (GHG) fluxes into the atmosphere. Aquaculture ponds cover an extremely large area in China's entire coastal zone. Knowledge of greenhouse gas fluxes from aquaculture ponds is very limited, but measuring GHG fluxes from aquaculture ponds is fundamental for estimating their impact on global warming. This study investigated the magnitude of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) fluxes from two coastal aquaculture ponds during 2011 and 2012 in the Shanyutan wetland of the Min River estuary, southeastern China, and determined the factors that may regulate GHG fluxes from the two ponds. The average fluxes of CO2, CH4 and N2O were 20.78 mgCO2 m-2h-1, 19.95 mgCH4 m-2h-1 and 10.74 μgN2O m-2h-1, respectively, in the shrimp pond. The average fluxes of CO2, CH4 and N2O were -60.46 mgCO2 m-2h-1, 1.65 mgCH4 m-2h-1 and 11.8 μgN2O m-2h-1, respectively, in the mixed shrimp and fish aquaculture pond during the study period. The fluxes of all three gases showed distinct temporal variations. The variations in the GHG fluxes were influenced by interactions with the thermal regime, pH, trophic status and chlorophyll-a content. Significant differences in the CO2 and N2O fluxes between the shrimp pond and the mixed aquaculture pond were observed from September to November, whereas the CH4 fluxes from the two ponds were not significantly different. The difference in the CO2 flux likely was related to the effects of photosynthesis, biological respiration and the mineralization of organic matter, whereas the N2O fluxes were controlled by the interactions between nitrogen substrate availability and pH. Water salinity, trophic status and dissolved oxygen concentration likely affected CH4 emission. Our results suggest that subtropical coastal aquaculture ponds are important contributors to regional CH4 and N2O emissions into the atmosphere, and their contribution to global warming must be considered

  5. Emissions of greenhouse gases from agriculture, land-use change, and forestry in the Gambia.

    PubMed

    Jallow, B P

    1995-01-01

    The Gambia has successfully completed a national greenhouse gas emissions inventory based on the results of a study funded by the United Nations Environment Programme (UNEP)/Global Environment Facility (GEF) Country Case Study Program. The concepts of multisectoral, multidisciplinary, and interdisciplinary collaboration were most useful in the preparation of this inventory. New data were gathered during the study period, some through regional collaboration with institutions such as Environment and Development in the Third World (ENDA-TM) Energy Program and the Ecological Monitoring Center in Dakar, Senegal, and some through national surveys and the use of remote sensing techniques, as in the Bushfires Survey. Most of the data collected are used in this paper. The Intergovernmental Panel on Climate Change/Organisation for Economic Co-operation and Development/International Energy Agency (IPCC/OECD/IEA) methodology is used to calculate greenhouse gas emissions. Many of the default data in the IPCC/OECD/IEA methodology have also been used. Overall results indicate that in the biomass sectors (agriculture, forestry, and land-use change) carbon dioxide (CO2) is emitted most, with a total of 1.7 Tg. This is followed by methane (CH4), 22.3 Gg; carbon monoxide (CO), 18.7 Gg; nitrogen oxides (NOx), 0.3 Gg; and nitrous oxide (N2O), 0.014 Gg. The Global Warming Potential (GWP) was used as an index to describe the relative effects of the various gases reported here. Based on the emissions in The Gambia in 1993, it was found that CO2 will contribute 75%, CH4 about 24.5%, and N2O 0.2% of the warming expected in the 100-year period beginning in 1993. The results in this analysis are limited by the shortcomings of the IPCC/OECD/IEA methodology and scarce national data. Because the methodology was developed outside of the developing world, most of its emissions factors and coefficients were developed and tested in environments that are very different from The Gambia. This is likely

  6. Measurement and modelling of the sources and sinks of greenhouse gases from northern wetlands

    NASA Astrophysics Data System (ADS)

    Roulet, N. T.; Frolking, S.; Lafleur, P. M.; Moore, T. R.; Richard, P. H. J.

    2003-04-01

    Northern wetlands contain ≈30% of the world's terrestrial carbon store, resulting from the incomplete decomposition of plant material inhibited because oxygen diffusion is limited by water saturation of the soil. While this behaviour results in a sink for CO_2, anaerobic pathways of decomposition result in wetlands being a large, but variable, source of CH_4. Northern wetlands tend to be nitrogen-impoverished, therefore they are not an important source of N_2O. However, nitrogen deposition, peat extraction, and other land-use changes have the potential to alter their greenhouse gas (GHG) sink/source function. Until recently, most of the studies on the atmosphere-biosphere exchange of greenhouse gases from northern wetlands were short-term and seasonal. In 1998 the Peatland Carbon Study began continuous measurements of the carbon dynamics of a northern peatland and developed several ecosystem models to be used in simulations of the response of peatlands to climate variability and change. The continuous measurements have established the dominant role of climate variability in determining the magnitude and sign of the fluxes of GHGs. The Peatland Carbon Simulator (PCARS) was developed to use either direct measurements or modeled climate from a land surface process model such as the Canadian Land Surface Scheme (CLASS) which has been modified to incorporate the physical attributes of wetlands as inputs. PCARS illustrates the relative importance of various components of the ecosystem in determining the inter-annual variability in GHG exchange. Evaluation of PCARS has helped identify significant gaps in our knowledge of peatland systems. A second, more phenomenological model, the Peat Accumulation Model (PAM), demonstrates the overall importance of precipitation in controlling decadal to millennial scale variations in sink/source strength of CO_2. The Canadian Global Coupled Climate Carbon Model (CGC^3M) Network is attempting to parameterize wetland processes for the

  7. Proceedings of the International Workshop on Sustainable ForestManagement: Monitoring and Verification of Greenhouse Gases

    SciTech Connect

    Sathaye , Jayant; Makundi , Willy; Goldberg ,Beth; Andrasko , Ken; Sanchez , Arturo

    1997-07-01

    The International Workshop on Sustainable Forest Management: Monitoring and Verification of Greenhouse Gases was held in San Jose, Costa Rica, July 29-31, 1996. The main objectives of the workshop were to: (1) assemble key practitioners of forestry greenhouse gas (GHG) or carbon offset projects, remote sensing of land cover change, guidelines development, and the forest products certification movement, to offer presentations and small group discussions on findings relevant to the crucial need for the development of guidelines for monitoring and verifying offset projects, and (2) disseminate the findings to interested carbon offset project developers and forestry and climate change policy makers, who need guidance and consistency of methods to reduce project transaction costs and increase probable reliability of carbon benefits, at appropriate venues. The workshop brought together about 45 participants from developed, developing, and transition countries. The participants included researchers, government officials, project developers, and staff from regional and international agencies. Each shared his or her perspectives based on experience in the development and use of methods for monitoring and verifying carbon flows from forest areas and projects. A shared sense among the participants was that methods for monitoring forestry projects are well established, and the techniques are known and used extensively, particularly in production forestry. Introducing climate change with its long-term perspective is often in conflict with the shorter-term perspective of most forestry projects and standard accounting principles. The resolution of these conflicts may require national and international agreements among the affected parties. The establishment of guidelines and protocols for better methods that are sensitive to regional issues will be an important first step to increase the credibility of forestry projects as viable mitigation options. The workshop deliberations led

  8. Greenhouse gases emission from soils under major crops in Northwest India.

    PubMed

    Jain, N; Arora, P; Tomer, R; Mishra, Shashi Vind; Bhatia, A; Pathak, H; Chakraborty, D; Kumar, Vinod; Dubey, D S; Harit, R C; Singh, J P

    2016-01-15

    Quantification of greenhouse gases (GHGs) emissions from agriculture is necessary to prepare the national inventories and to develop the mitigation strategies. Field experiments were conducted during 2008-2010 at the experimental farm of the Indian Agricultural Research Institute, New Delhi, India to quantify nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2) emissions from soils under cereals, pulses, millets, and oilseed crops. Total cumulative N2O emissions were significantly different (P>0.05) among the crop types. Emission of N2O as percentage of applied N was the highest in pulses (0.67%) followed by oilseeds (0.55%), millets (0.43%) and cereals (0.40%). The emission increased with increasing rate of N application (r(2)=0.74, P<0.05). The cumulative flux of CH4 from the rice crop was 28.64±4.40 kg ha(-1), while the mean seasonal integrated flux of CO2 from soils ranged from 3058±236 to 3616±157 kg CO2 ha(-1) under different crops. The global warming potential (GWP) of crops varied between 3053 kg CO2 eq. ha(-1) (pigeon pea) and 3968 kg CO2 eq. ha(-1) (wheat). The carbon equivalent emission (CEE) was least in pigeon pea (833 kg C ha(-1)) and largest in wheat (1042 kg C ha(-1)). The GWP per unit of economic yield was the highest in pulses and the lowest in cereal crops. The uncertainties in emission values varied from 4.6 to 22.0%. These emission values will be useful in updating the GHGs emission inventory of Indian agriculture. PMID:26540602

  9. Radiative Forcing by Long-Lived Greenhouse Gases: Calculations with the AER Radiative Transfer Models

    SciTech Connect

    Collins, William; Iacono, Michael J.; Delamere, Jennifer S.; Mlawer, Eli J.; Shephard, Mark W.; Clough, Shepard A.; Collins, William D.

    2008-04-01

    A primary component of the observed, recent climate change is the radiative forcing from increased concentrations of long-lived greenhouse gases (LLGHGs). Effective simulation of anthropogenic climate change by general circulation models (GCMs) is strongly dependent on the accurate representation of radiative processes associated with water vapor, ozone and LLGHGs. In the context of the increasing application of the Atmospheric and Environmental Research, Inc. (AER) radiation models within the GCM community, their capability to calculate longwave and shortwave radiative forcing for clear sky scenarios previously examined by the radiative transfer model intercomparison project (RTMIP) is presented. Forcing calculations with the AER line-by-line (LBL) models are very consistent with the RTMIP line-by-line results in the longwave and shortwave. The AER broadband models, in all but one case, calculate longwave forcings within a range of -0.20 to 0.23 W m{sup -2} of LBL calculations and shortwave forcings within a range of -0.16 to 0.38 W m{sup -2} of LBL results. These models also perform well at the surface, which RTMIP identified as a level at which GCM radiation models have particular difficulty reproducing LBL fluxes. Heating profile perturbations calculated by the broadband models generally reproduce high-resolution calculations within a few hundredths K d{sup -1} in the troposphere and within 0.15 K d{sup -1} in the peak stratospheric heating near 1 hPa. In most cases, the AER broadband models provide radiative forcing results that are in closer agreement with high 20 resolution calculations than the GCM radiation codes examined by RTMIP, which supports the application of the AER models to climate change research.

  10. Continuous measurements of greenhouse gases and atmospheric oxygen at the Namib Desert Atmospheric Observatory

    NASA Astrophysics Data System (ADS)

    Morgan, E. J.; Lavrič, J. V.; Seifert, T.; Chicoine, T.; Day, A.; Gomez, J.; Logan, R.; Sack, J.; Shuuya, T.; Uushona, E. G.; Vincent, K.; Schultz, U.; Brunke, E.-G.; Labuschagne, C.; Thompson, R. L.; Schmidt, S.; Manning, A. C.; Heimann, M.

    2015-06-01

    A new coastal background site has been established for observations of greenhouse gases (GHGs) in the central Namib Desert at Gobabeb, Namibia. The location of the site was chosen to provide observations for a data-poor region in the global sampling network for GHGs. Semi-automated continuous measurements of carbon dioxide, methane, nitrous oxide, carbon monoxide, atmospheric oxygen, and basic meteorology are made at a height of 21 m a.g.l., 50 km from the coast at the northern border of the Namib Sand Sea. Atmospheric oxygen is measured with a differential fuel cell analyzer (DFCA). Carbon dioxide and methane are measured with an early-model cavity ring-down spectrometer (CRDS); nitrous oxide and carbon monoxide are measured with an off-axis integrated cavity output spectrometer (OA-ICOS). Instrument-specific water corrections are employed for both the CRDS and OA-ICOS instruments in lieu of drying. The performance and measurement uncertainties are discussed in detail. As the station is located in a remote desert environment, there are some particular challenges, namely fine dust, high diurnal temperature variability, and minimal infrastructure. The gas handling system and calibration scheme were tailored to best fit the conditions of the site. The CRDS and DFCA provide data of acceptable quality when base requirements for operation are met, specifically adequate temperature control in the laboratory and regular supply of electricity. In the case of the OA-ICOS instrument, performance is significantly improved through the implementation of a drift correction through frequent measurements of a reference cylinder.

  11. Ammonia, Total Reduced Sulfides, and Greenhouse Gases of Pine Chip and Corn Stover Bedding Packs.

    PubMed

    Spiehs, Mindy J; Brown-Brandl, Tami M; Parker, David B; Miller, Daniel N; Berry, Elaine D; Wells, James E

    2016-03-01

    Bedding materials may affect air quality in livestock facilities. Our objective in this study was to compare headspace concentrations of ammonia (NH), total reduced sulfides (TRS), carbon dioxide (CO), methane (CH), and nitrous oxide (NO) when pine wood chips ( spp.) and corn stover ( L.) were mixed in various ratios (0, 10, 20, 30, 40, 60, 80, and 100% pine chips) and used as bedding with manure. Air samples were collected from the headspace of laboratory-scaled bedded manure packs weekly for 42 d. Ammonia concentrations were highest for bedded packs containing 0, 10, and 20% pine chips (equivalent to 501.7, 502.3, and 502.3 mg m, respectively) in the bedding mixture and were lowest when at least 80% pine chips were used as bedding (447.3 and 431.0 mg m, respectively for 80 and 100% pine chip bedding). The highest NH concentrations were observed at Day 28. The highest concentration of TRS was observed when 100% pine chips were used as bedding (11.4 µg m), with high concentrations occurring between Days 7 and 14, and again at Day 35. Greenhouse gases were largely unaffected by bedding material but CH and CO concentrations increased as the bedded packs aged and NO concentrations were highly variable throughout the incubation. We conclude that a mixture of bedding material that contains 30 to 40% pine chips may be the ideal combination to reduce both NH and TRS emissions. All gas concentrations increased as the bedded packs aged, suggesting that frequent cleaning of facilities would improve air quality in the barn, regardless of bedding materials used. PMID:27065410

  12. A robust optical parametric oscillator and receiver telescope for differential absorption lidar of greenhouse gases

    NASA Astrophysics Data System (ADS)

    Robinson, Iain; Jack, James W.; Rae, Cameron F.; Moncrieff, John B.

    2015-10-01

    We report the development of a differential absorption lidar instrument (DIAL) designed and built specifically for the measurement of anthropogenic greenhouse gases in the atmosphere. The DIAL is integrated into a commercial astronomical telescope to provide high-quality receiver optics and enable automated scanning for three-dimensional lidar acquisition. The instrument is portable and can be set up within a few hours in the field. The laser source is a pulsed optical parametric oscillator (OPO) which outputs light at a wavelength tunable near 1.6 μm. This wavelength region, which is also used in telecommunications devices, provides access to absorption lines in both carbon dioxide at 1573 nm and methane at 1646 nm. To achieve the critical temperature stability required for a laserbased field instrument the four-mirror OPO cavity is machined from a single aluminium block. A piezoactuator adjusts the cavity length to achieve resonance and this is maintained over temperature changes through the use of a feedback loop. The laser output is continuously monitored with pyroelectric detectors and a custom-built wavemeter. The OPO is injection seeded by a temperature-stabilized distributed feedback laser diode (DFB-LD) with a wavelength locked to the absorption line centre (on-line) using a gas cell containing pure carbon dioxide. A second DFB-LD is tuned to a nearby wavelength (off-line) to provide the reference required for differential absorption measurements. A similar system has been designed and built to provide the injection seeding wavelengths for methane. The system integrates the DFB-LDs, drivers, locking electronics, gas cell and balanced photodetectors. The results of test measurements of carbon dioxide are presented and the development of the system is discussed, including the adaptation required for the measurement of methane.

  13. Continuous measurements of greenhouse gases and atmospheric oxygen at the Namib Desert Atmospheric Observatory

    NASA Astrophysics Data System (ADS)

    Morgan, E. J.; Lavrič, J. V.; Seifert, T.; Chicoine, T.; Day, A.; Gomez, J.; Logan, R.; Sack, J.; Shuuya, T.; Uushona, E. G.; Vincent, K.; Schultz, U.; Brunke, E.-G.; Labuschagne, C.; Thompson, R. L.; Schmidt, S.; Manning, A. C.; Heimann, M.

    2015-02-01

    A new coastal background site has been established for observations of greenhouse gases (GHGs) in the central Namib Desert at Gobabeb, Namibia. The location of the site was chosen to provide observations for a data-poor region in the global sampling network for GHGs. Semi-automated, continuous measurements of carbon dioxide, methane, nitrous oxide, carbon monoxide, atmospheric oxygen, and basic meteorology are made at a height of 21 m a.g.l., 50 km from the coast at the northern border of the Namib Sand Sea. Atmospheric oxygen is measured with a differential fuel cell analyzer (DFCA). Carbon dioxide and methane are measured with an early-model cavity ring-down spectrometer (CRDS); nitrous oxide and carbon monoxide are measured with an off-axis integrated cavity output spectrometer (OA-ICOS). Instrument-specific water corrections are employed for both the CRDS and OA-ICOS instruments in lieu of drying. The performance and measurement uncertainties are discussed in detail. As the station is located in a remote desert environment, there are some particular challenges, namely fine dust, high diurnal temperature variability, and minimal infrastructure. The gas handling system and calibration scheme were tailored to best fit the conditions of the site. The CRDS and DFCA provide data of acceptable quality when base requirements for operation are met, specifically adequate temperature control in the laboratory and regular supply of electricity. In the case of the OA-ICOS instrument, performance is significantly improved through the implementation of a drift correction through frequent measurements of a working tank.

  14. Emissions of ammonia and greenhouse gases during combined pre-composting and vermicomposting of duck manure.

    PubMed

    Wang, Jinzhi; Hu, Zhengyi; Xu, Xingkai; Jiang, Xia; Zheng, Binghui; Liu, Xiaoning; Pan, Xubin; Kardol, Paul

    2014-08-01

    Combined pre-composting and vermicomposting has shown potential for reclamation of solid wastes, which is a significant source of ammonia (NH3), and greenhouse gases (GHG), including nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2). Earthworms and amendments may both affect physico-chemical characteristics that control gas-producing processes, and thus affect NH3 and GHG emissions. Here, we used two-way ANOVA to test the effects of addition of reed straw and combined addition of reed straw and zeolite on NH3 and GHG emissions during pre-composting of duck manure, either with or without a follow-up phase of vermicomposting. Results showed that cumulative N2O, CH4, and CO2 emissions during pre-composting and vermicomposting ranged from 92.8, 5.8, and 260.6 mg kg(-)(1) DM to 274.2, 30.4, and 314.0 mg kg(-1) DM, respectively. Earthworms and amendments significantly decreased N2O and CH4 emissions. Emission of CO2 was not affected by earthworms, but increased in responses to addition of reed straw. Cumulative NH3 emission ranged from 3.0 to 8.1 g kg(-1) DM, and was significantly decreased by reed straw and zeolite addition. In conclusion, combined pre-composting and vermicomposting with reed straw and zeolite addition would be strongly recommended in mitigating emissions of N2O, CH4, and NH3 from duck manure. Moreover, this method also provides nutrient-rich products that can be used as a fertilizer. PMID:24835490

  15. Origins and seasonality of greenhouse gases over the South Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Arnold, Sabrina G.; Feist, Dietrich G.; Wang, Zhiting

    2016-04-01

    The Total Carbon Column Observing Network (TCCON) has become the reference network for all total-column observations of greenhouse gases (GHGs) like CO2, CH4, CO, N2O and others. Within TCCON, the Max Planck Institute for Biogeochemistry (MPI-BGC) has been operating a Fourier-Transform Spectrometer (FTS) on Ascension Island (8°S, 14°W) since May 2012. This is currently the only TCCON station covering the South Atlantic Ocean. So far, the measurements span more than two complete seasonal cycles. Due to its location in the southern trade wind zone, the station is downwind from Africa most of the time. A detailed trajectory analysis shows that different parts of the total atmospheric column typically have different origins. Air in the Planetary Boundary Layer (PBL) typically comes from the deep southern Atlantic Ocean and had only little GHG exchange with land surfaces. However, air in the free troposphere above the PBL usually comes from tropical and southern Africa and sometimes also from South America. A detailed analysis allowed us to separate the total column of CH4 into a tropospheric and stratospheric part. Together with independent flask measurements from the surface, the effects of the different origins of air parcels can be seen in the PBL, the free troposphere and the stratosphere. For example, there are striking differences in seasonality for CH4 between the PBL and the free troposphere. Unlike over typical land stations, trace gas concentrations in the free troposphere above Ascension Island seem to be generally much higher than near the surface. Above the PBL, there is a whole layer of GHGs transported from Africa which shows land seasonal effects and biomass burning signals. This layer remains undetectable for surface observations.

  16. Mean Climate Controls on the Simulated Response of ENSO to Increasing Greenhouse Gases

    NASA Astrophysics Data System (ADS)

    Di Nezio, P. N.; Kirtman, B. P.; Clement, A. C.; Lee, S.; Vecchi, G. A.; Wittenberg, A. T.

    2012-12-01

    Climate model experiments are analyzed to elucidate if and how the changes in mean climate in response to doubling of atmospheric CO2 (2xCO2) influence ENSO. The processes involved the development, transition, and decay of simulated ENSO events are quantified through a multi-model heat budget analysis. The simulated changes in ENSO amplitude in response to 2xCO2 are directly related to changes in the anomalous ocean heat flux convergence during the development, transition, and decay of ENSO events. This consistency relationship results from the Bjerknes feedback and cannot be used to attribute the changes in ENSO. In order to avoid a circular argument, we compute the anomalous heat flux convergence due to the interaction of the ENSO anomalies in the pre-industrial climate with the 2xCO2 changes in mean climate. The weakening of the Walker circulation and the increased thermal stratification, both robust features of the mean climate response to 2xCO2, play opposing roles in ENSO - mean climate interactions. Weaker upwelling in response to a weaker Walker circulation drives a reduction in thermocline-driven ocean heat flux convergence (i.e., thermocline feedback), and thus reduces the ENSO amplitude. Conversely, a stronger zonal subsurface temperature gradient, associated with the increased thermal stratification, drives an increase in zonal current-induced ocean heat flux convergence (i.e., zonal advection feedback), and thus increases the ENSO amplitude. These opposing processes explain the lack of model agreement in whether ENSO is going to weaken or strengthen in response to increasing greenhouse gases, but also why ENSO appears to be relatively insensitive to 2xCO2 in most models.

  17. Greenhouse gases observation from space -initial operation and calibration results of TANSO on GOSAT- (Invited)

    NASA Astrophysics Data System (ADS)

    Kuze, A.; Shiomi, K.; Suto, H.; Nakajima, M.

    2009-12-01

    The Greenhouse gases Observing SATellite (GOSAT) observes carbon dioxide (CO2) and methane (CH4) globally from space. It is a joint project of Japan Aerospace Exploration Agency (JAXA), Ministry of the Environment (MOE) and National Institute for Environmental Studies (NIES). GOSAT was launched on January 23, 2009 from Tanegashima Space Center and placed in a 666 km sun-synchronous orbit of 12:48 local time, with an inclination angle of 98 deg. There are two instruments: the Thermal And Near infrared Sensor for carbon Observation Fourier-Transform Spectrometer (TANSO-FTS) detects gas absorption spectra of Short Wave InfraRed (SWIR) reflected on the earth's surface as well as of Thermal InfraRed (TIR) radiated from the ground and the atmosphere. TANSO-FTS is capable of detecting wide spectral coverage; three narrow bands (0.76, 1.6, and 2μm) and a wide band (5.5-14.3 μm) with 0.27 cm-1 spectral resolution. The TANSO Cloud and Aerosol Imager (TANSO-CAI) is a radiometer of ultraviolet (UV), visible, and SWIR to detect cloud and aerosol interference. TANSO-FTS and CAI acquire global data every three days. For the first six months after the launch, on-orbit function, performance, calibration, and validation have been checked-out. The presentation includes instrument design, pre-launch test results, observation plan, onboard calibration schemes, and the initial on-orbit results of radiometric, geometric and spectroscopic performances. The data processing on the ground is also presented.

  18. Modern to millennium-old greenhouse gases emitted from freshwater ecosystems of the eastern Canadian Arctic

    NASA Astrophysics Data System (ADS)

    Bouchard, F.; Laurion, I.; Preskienis, V.; Fortier, D.; Xu, X.; Whiticar, M. J.

    2015-07-01

    Ponds and lakes are widespread across the rapidly changing permafrost environments. Aquatic systems play an important role in global biogeochemical cycles, especially in greenhouse gas (GHG) exchanges between terrestrial systems and the atmosphere. The source, speciation and emission of carbon released from permafrost landscapes are strongly influenced by local specific conditions rather than general environmental setting. This study reports on GHG ages and emission rates from aquatic systems on Bylot Island in the eastern Canadian Arctic. Dissolved and ebullition gas samples were collected during the summer season from different types of water bodies located in a highly dynamic periglacial valley: polygonal ponds, collapsed ice-wedge trough ponds, and larger lakes overlying unfrozen soils (talik). The results showed strikingly different ages and fluxes depending on aquatic system types. Polygonal ponds were net sinks of dissolved CO2, but variable sources of dissolved CH4. They presented the highest ebullition fluxes, one or two orders of magnitude higher than from other ponds and lakes. Trough ponds appeared as substantial GHG sources, especially when their edges were actively eroding. Both types of ponds produced modern to hundreds of years old (<550 yr BP) GHG, even if trough ponds could contain much older carbon (>2000 yr BP) derived from freshly eroded peat. Lakes had small dissolved and ebullition fluxes, however they released much older GHG, including millennium-old CH4 (up to 3500 yr BP) sampled from lake central areas. Acetoclastic methanogenesis dominated at all study sites and there was minimal, if any, methane oxidation in gas emitted through ebullition. These findings provide new insights on the variable role of permafrost aquatic systems as a positive feedback mechanism on climate.

  19. O(1D) kinetic study of key ozone depleting substances and greenhouse gases.

    PubMed

    Baasandorj, Munkhbayar; Fleming, Eric L; Jackman, Charles H; Burkholder, James B

    2013-03-28

    A key stratospheric loss process for ozone depleting substances (ODSs) and greenhouse gases (GHGs) is reaction with the O((1)D) atom. In this study, rate coefficients, k, for the O((1)D) atom reaction were measured for the following key halocarbons: chlorofluorocarbons (CFCs) CFCl3 (CFC-11), CF2Cl2 (CFC-12), CFCl2CF2Cl (CFC-113), CF2ClCF2Cl (CFC-114), CF3CF2Cl (CFC-115); hydrochlorofluorocarbons (HCFCs) CHF2Cl (HCFC-22), CH3CClF2 (HCFC-142b); and hydrofluorocarbons (HFCs) CHF3 (HFC-23), CHF2CF3 (HFC-125), CH3CF3 (HFC-143a), and CF3CHFCF3 (HFC-227ea). Total rate coefficients, kT, corresponding to the loss of the O((1)D) atom, were measured over the temperature range 217-373 K using a competitive reactive technique. kT values for the CFC and HCFC reactions were >1 × 10(-10) cm(3) molecule(-1) s(-1), except for CFC-115, and the rate coefficients for the HFCs were in the range (0.095-0.72) × 10(-10) cm(3) molecule(-1) s(-1). Rate coefficients for the CFC-12, CFC-114, CFC-115, HFC-23, HFC-125, HFC-143a, and HFC-227ea reactions were observed to have a weak negative temperature dependence, E/R ≈ -25 K. Reactive rate coefficients, kR, corresponding to the loss of the halocarbon, were measured for CFC-11, CFC-115, HCFC-22, HCFC-142b, HFC-23, HFC-125, HFC-143a, and HFC-227ea using a relative rate technique. The reactive branching ratio obtained was dependent on the composition of the halocarbon and the trend in O((1)D) reactivity with the extent of hydrogen and chlorine substitution is discussed. The present results are critically compared with previously reported kinetic data and the discrepancies are discussed. 2D atmospheric model calculations were used to evaluate the local and global annually averaged atmospheric lifetimes of the halocarbons and the contribution of O((1)D) chemistry to their atmospheric loss. The O((1)D) reaction was found to be a major global loss process for CFC-114 and CFC-115 and a secondary global loss process for the other molecules included

  20. The GHG-CCI Project to Deliver the Essential Climate Variable Greenhouse Gases: Current status

    NASA Astrophysics Data System (ADS)

    Buchwitz, M.; Boesch, H.; Reuter, M.

    2012-04-01

    The GHG-CCI project (http://www.esa-ghg-cci.org) is one of several projects of ESA's Climate Change Initiative (CCI), which will deliver various Essential Climate Variables (ECVs). The goal of GHG-CCI is to deliver global satellite-derived data sets of the two most important anthropogenic greenhouse gases (GHGs) carbon dioxide (CO2) and methane (CH4) suitable to obtain information on regional CO2 and CH4 surface sources and sinks as needed for better climate prediction. The GHG-CCI core ECV data products are column-averaged mole fractions of CO2 and CH4, XCO2 and XCH4, retrieved from SCIAMACHY on ENVISAT and TANSO on GOSAT. Other satellite instruments will be used to provide constraints in upper layers such as IASI, MIPAS, and ACE-FTS. Which of the advanced algorithms, which are under development, will be the best for a given data product still needs to be determined. For each of the 4 GHG-CCI core data products - XCO2 and XCH4 from SCIAMACHY and GOSAT - several algorithms are bing further developed and the corresponding data products are inter-compared to identify which data product is the most appropriate. This includes comparisons with corresponding data products generated elsewhere, most notably with the operational data products of GOSAT generated at NIES and the NASA/ACOS GOSAT XCO2 product. This activity, the so-called "Round Robin exercise", will be performed in the first two years of this project. At the end of the 2 year Round Robin phase (end of August 2012) a decision will be made which of the algorithms performs best. The selected algorithms will be used to generate the first version of the ECV GHG. In the last six months of this 3 year project the resulting data products will be validated and made available to all interested users. In the presentation and overview about this project will be given focussing on the latest results.

  1. Emissions of ammonia and greenhouse gases during combined pre-composting and vermicomposting of duck manure

    SciTech Connect

    Wang, Jinzhi; Hu, Zhengyi; Xu, Xingkai; Jiang, Xia; Zheng, Binghui; Liu, Xiaoning; Pan, Xubin; Kardol, Paul

    2014-08-15

    Highlights: • Earthworms significantly decreased emissions of N{sub 2}O and CH{sub 4}, but had a marginal effect on CO{sub 2} emission. • NH{sub 3}, N{sub 2}O, and CH{sub 4} emissions were significantly reduced by reed straw and zeolite, CO{sub 2} emission was increased by reed straw. • Combined pre-composting and vermicomposting with reed straw and zeolite would be recommended for disposal of duck manure. - Abstract: Combined pre-composting and vermicomposting has shown potential for reclamation of solid wastes, which is a significant source of ammonia (NH{sub 3}), and greenhouse gases (GHG), including nitrous oxide (N{sub 2}O), methane (CH{sub 4}), and carbon dioxide (CO{sub 2}). Earthworms and amendments may both affect physico-chemical characteristics that control gas-producing processes, and thus affect NH{sub 3} and GHG emissions. Here, we used two-way ANOVA to test the effects of addition of reed straw and combined addition of reed straw and zeolite on NH{sub 3} and GHG emissions during pre-composting of duck manure, either with or without a follow-up phase of vermicomposting. Results showed that cumulative N{sub 2}O, CH{sub 4}, and CO{sub 2} emissions during pre-composting and vermicomposting ranged from 92.8, 5.8, and 260.6 mg kg{sup −1} DM to 274.2, 30.4, and 314.0 mg kg{sup −1} DM, respectively. Earthworms and amendments significantly decreased N{sub 2}O and CH{sub 4} emissions. Emission of CO{sub 2} was not affected by earthworms, but increased in responses to addition of reed straw. Cumulative NH{sub 3} emission ranged from 3.0 to 8.1 g kg{sup −1} DM, and was significantly decreased by reed straw and zeolite addition. In conclusion, combined pre-composting and vermicomposting with reed straw and zeolite addition would be strongly recommended in mitigating emissions of N{sub 2}O, CH{sub 4}, and NH{sub 3} from duck manure. Moreover, this method also provides nutrient-rich products that can be used as a fertilizer.

  2. Decomposition of Potent Greenhouse Gases SF6, CF4 and SF5CF3 by Dielectric Barrier Discharge

    NASA Astrophysics Data System (ADS)

    Zhang, Renxi; Wang, Jingting; Cao, Xu; Hou, Huiqi

    2016-04-01

    For their distinguished global warming potential (GWP100) and long atmosphere lifespan, CF4, SF6 and SF5CF3 were significant in the field of greenhouse gas research. The details of discharging character and the optimal parameter were discussed by using a Dielectric Barrier Discharge (DBD) reactor to decompose these potent greenhouse gases in this work. The results showed that SF6 could be decomposed by 92% under the conditions of 5 min resident time and 3000 V applied voltage with the partial pressure of 2.0 kPa, 28.2 kPa, and 1.8 kPa for SF6, air and water vapor, respectively. 0.4 kPa CF4 could be decomposed by 98.2% for 4 min resident time with 30 kPa Ar added. The decomposition of SF5CF3 was much more effective than that of SF6 and CF4 and moreover, 1.3 kPa SF5CF3, discharged with 30 kPa O2, Ar and air, could not be detected when the resident time was 80 s, 40 s, and 120 s, respectively. All the results indicated that DBD was a feasible technique for the abatement of potent greenhouse gases. supported by National Natural Science Foundation of China (Nos. 20507004, 21577023)

  3. Ecosystem Metabolism and Air-Water Fluxes of Greenhouse Gases in High Arctic Wetland Ponds

    NASA Astrophysics Data System (ADS)

    Lehnherr, I.; Venkiteswaran, J.; St. Louis, V. L.; Emmerton, C.; Schiff, S. L.

    2012-12-01

    Freshwater lakes and wetlands can be very productive systems on the Arctic landscape compared to terrestrial tundra ecosystems and provide valuable resources to many organisms, including waterfowl, fish and humans. Rates of ecosystem productivity dictate how much energy flows through food webs, impacting the abundance of higher-level organisms (e.g., fish), as well as the net carbon balance, which determines whether a particular ecosystem is a source or sink of carbon. Climate change is predicted to result in warmer temperatures, increased precipitation and permafrost melting in the Arctic and is already altering northern ecosystems at unprecedented rates; however, it is not known how freshwater systems are responding to these changes. To predict how freshwater systems will respond to complex environmental changes, it is necessary to understand the key processes, such as primary production and ecosystem respiration, that are driving these systems. We sampled wetland ponds (n=8) and lakes (n=2) on northern Ellesmere Island (81° N, Nunavut, Canada) during the open water season for a suite of biogeochemical parameters, including concentrations of dissolved gases (O2, CO2, CH4, N2O) as well as stable-isotope ratios of dissolved inorganic carbon (δ13C-DIC), dissolved oxygen (δ18O-DO), and water (δ18O-H2O). We will present rates of primary production and ecosystem respiration, modeled from the concentration and stable isotope ratios of DIC and DO, as well as air-water gas exchange of greenhouse gases in these high Arctic ponds and lakes. Preliminary results demonstrate that ecosystem metabolism in these ponds was high enough to result in significant deviations in the isotope ratios of DIC and DO from atmospheric equilibrium conditions. In other words ecosystem rates of primary production and respiration were faster than gas exchange even in these small, shallow, well-mixed ponds. Furthermore, primary production was elevated enough at all sites except Lake Hazen, a

  4. MAGGnet: An international network to foster mitigation of agricultural greenhouse gases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Research networks provide a framework for review, synthesis, and systematic testing of theories by multiple scientists across international borders critical for addressing global-scale issues. In 2012, a greenhouse gas (GHG) research network referred to as MAGGnet (Managing Agricultural Greenhouse ...

  5. 76 FR 36339 - Mandatory Reporting of Greenhouse Gases: Additional Sources of Fluorinated GHGs: Extension of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-22

    ... Regulations EPA U.S. Environmental Protection Agency FR Federal Register GHG greenhouse gas mm millimeters...: Electronics Manufacturing of the Greenhouse Gas Reporting Rule on December 1, 2010 (75 FR 74774). This subpart... Order 12866 (58 FR 51735, October 4, 1993) and, therefore, not subject to review under Executive...

  6. 76 FR 59533 - Mandatory Reporting of Greenhouse Gases: Petroleum and Natural Gas Systems: Revisions to Best...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-27

    .... Currently, according to the provisions in 76 FR 22825 (April 25, 2011), owners and operators subject to 40.... Environmental Protection Agency. FR Federal Register. GHG greenhouse gas. ICR Information Collection Request... Systems of the Greenhouse Gas Reporting Rule on November 30, 2010, 40 CFR part 98, subpart W (75 FR...

  7. Quantifying urban/industrial emissions of greenhouse and ozone-depleting gases based on atmospheric observations

    NASA Astrophysics Data System (ADS)

    Barnes, Diana Hart

    2000-11-01

    Background and pollution trends and cycles of fourteen trace gases over the Northeastern U.S. are inferred from continuous atmospheric observations at the Harvard Forest research station located in Petersham, Massachusetts. This site receives background `clean' air from the northwest (Canada) and `dirty' polluted air from the southwest (New York City-Washington, D.C. corridor). Mixing ratios of gases regulated by the Montreal Protocol or other policies (CO, PCE, CFC11, CFC12, CFC113, CH 3CCl3, CCl4, and Halon-1211) and of those not subject to restrictions (H2, CH4, CHCl3, TCE, N2O, and SF6) were measured over the three-year period, 1996 to 1998, every 24 minutes by a fully automated gas chromatographic instrument with electron capture detectors. Evidence for polar vortex venting is found consistently in the month of June of the background seasonal cycles. The ratio of CO and PCE enhancements borne on southwesterly winds are in excellent agreement with county-level EPA and sales-based inventories for the New York City-Washington, D.C. region. From this firm footing, we use CO and PCE as reference compounds to determine the urban/industrial source strengths for the other species. A broad historical and geographic study of emissions reveals that the international treaty has by and large been a success. Locally, despite the passing of the 1996 Montreal Protocol ban, only emissions of CFC12 and CH3CCl3 are abating. Though source strengths are waning, the sources are not spent and continued releases to the atmosphere may be expected for some years to come. For CH3CCl3, whose rate of decline is central to our understanding of atmospheric processes, we estimate that absolute concentrations may persist until around the year 2010. The long-term high frequency time series of hydrogen provided here represents the first such data set of its kind. The H2 diurnal cycle is established and explained in terms of its sources and sinks. The ratio of H2 to CO in pollution plumes is

  8. Atmospheric Feedbacks By Greenhouse Gases From Baltic Bogs During Late Holocene Reconstructed Using Wetness Anomalies

    NASA Astrophysics Data System (ADS)

    Alm, J.; Sillasoo, Ü.; Endjärv, E.; Lode, E.; Blundell, A.; Charman, D.; Väliranta, M.; Laine, J. K.; Tuittila, E.; Seppä, H.; Korhola, A.; Karofeld, E.

    2006-12-01

    Climate changes are documented in multiple proxies in sediments such as peat. At the same time, information on ecosystem feedbacks in terms of greenhouse gas balances can be derived from the proxies. As part of the EU-project ACCROTELM, we headed to building peat-based multi-proxy datasets from Finnish and Estonian sites over the past 4500 years. The cores were 14C-dated using AMS, and the high resolution age-depth curves were assumed by wiggle matching. We sampled the peat cores with a resolution of 1 cm at least every at 4th cm and analyzed plant macrofossils, testate amoebae, and carbon accumulation rates. At least a decadal resolution was obtained for the 1 cm sample slices throughout the cores. We also sampled current testate amoebae communities at different microsites of vegetation varying in moisture conditions, in order to compile a transfer function for water tables. These reconstructions were attributed with spatial proportions of mire microsites, derived in GIS from aerial images. We reviewed the methane emission and carbon accumulation history of the bog landscape as GWP using the time series of GHG balances over the 4,5 millennia. Special attention was paid for the periods of rapid climatic excursions with wet or dry shifts. The climatic feedbacks, i.e. CO2 deposition from bulk density and C content, and CH4 modeled as function of wetness, were combined in CO2 equivalents. Although the bogs were carbon sinks, the apparent impact was net atmospheric warming, through the dynamics of CH4 release. Burning of peat in the fires located in the sediment cores must have increased the net warming effect. The temporal correlations between the bogs south and north from the Gulf of Finland are inspected.

  9. Codes and regulations governing handling, storage, use and release of toxic gases

    NASA Astrophysics Data System (ADS)

    Bolmen, Richard A.

    1988-07-01

    To control the hazards associated with the handling, storage, use and release of toxic gases in the manufacturing process, a number of codes and regulations have been promulgated. At the forefront of these regulations are the Uniform Fire Code (UFC), Article 51, ``Semiconductor Fabrication Facilities Using Hazardous Production Materials,'' 1985 Edition; UFC Article 80, ``Hazardous Materials,'' 1987 Revision; and the Toxic Gas Model Ordinance, California Assembly Bill 1021. Article 51 of the UFC is specific for semiconductor wafer fabrication facilities and regulates the storage, handling and use of hazardous production materials. Article 80 of the UFC has a much broader scope and incorporates requirements for prevention, control and mitigation of dangerous conditions related to hazardous materials. As it applies to toxic gases, Article 80 incorporates Article 51 requirements and in addition requires treatment systems to reduce discharge concentrations and mitigate unauthorized releases of toxic gases. The Toxic Gas Model Ordinance is specific to toxic gases and regulates storage, handling and use of toxic gases at new and existing facilities incorporating monitoring and treatment systems should an unauthorized release occur. This paper will focus on these regulations as they apply to toxic gases used by the semiconductor and photovoltaics industries.

  10. Opportunities for Coordinated Observations of CO2 with the Orbiting Carbon Observatory (OCO) and Greenhouse Gases Observing Satellite (GOSAT)

    NASA Technical Reports Server (NTRS)

    Crisp, David

    2008-01-01

    The Orbiting Carbon Observatory (OCO) and the Greenhouse Gases Observing Satellite (GOSAT) are the first two satellites designed to make global measurements of atmospheric carbon dioxide (CO2) with the precision and sampling needed identify and monitor surface sources and sinks of this important greenhouse gas. Because the operational phases of the OCO and GOSAT missions overlap in time, there are numerous opportunities for comparing and combining the data from these two satellites to improve our understanding of the natural processes and human activities that control the atmospheric CO2 and it variability over time. Opportunities for cross-calibration, cross-validation, and coordinated observations that are currently under consideration are summarized here.

  11. Non-CO2 Greenhouse Gases in the Second Generation Model

    SciTech Connect

    Fawcett, Allen A.; Sands, Ronald D.

    2006-12-29

    The Second Generation Model (SGM) was developed for the purpose of analyzing policies designed to reduce greenhouse gas emissions. This paper documents how greenhouse gas emissions are calculated in the SGM, an application to several Energy Modeling Forum scenarios that stabilize radiative forcing by using policies that either exclusively limit CO2 emissions or include both CO2 and non-CO2 greenhouse gasses, and an extension including advanced fossil generating technologies with CO2 capture and storage in the USA region of the SGM.

  12. Impact of rising greenhouse gases on mid-latitude storm tracks and associated hydroclimate variability and change

    SciTech Connect

    Seager, Richard

    2014-12-08

    Project Summary This project aimed to advance physical understanding of how and why the mid-latitude jet streams and storm tracks shift in intensity and latitude in response to changes in radiative forcing with an especial focus on rising greenhouse gases. The motivation, and much of the work, stemmed from the importance that these mean and transient atmospheric circulation systems have for hydroclimate. In particular drying and expansion of the subtropical dry zones has been related to a poleward shift of the mid-latitude jets and storm tracks. The work involved integrated assessment of observation and model projections as well as targeted model simulations.

  13. Optimization Model for Reducing Emissions of Greenhouse Gases from Automobiles (OMEGA)

    EPA Science Inventory

    The EPA Vehicle Greenhouse Gas (VGHG) model is used to apply various technologies to a defined set of vehicles in order to meet a specified GHG emission target, and to then calculate the costs and benefits of doing so.

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

    EPA Science Inventory

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

  15. An alternative approach to establishing trade-offs among greenhouse gases.

    PubMed

    Manne, A S; Richels, R G

    2001-04-01

    The Kyoto Protocol permits countries to meet part of their emission reduction obligations by cutting back on gases other than CO2 (ref. 1). This approach requires a definition of trade-offs among the radiatively active gases. The Intergovernmental Panel on Climate Change has suggested global warming potentials for this purpose, which use the accumulated radiative forcing of each gas by a set time horizon to establish emission equivalence. But it has been suggested that this approach has serious shortcomings: damages or abatement costs are not considered and the choice of time horizon for calculating cumulative radiative force is critical, but arbitrary. Here we describe an alternative framework for determining emission equivalence between radiatively active gases that addresses these weaknesses. We focus on limiting temperature change and rate of temperature change, but our framework is also applicable to other objectives. For a proposed ceiling, we calculate how much one should be willing to pay for emitting an additional unit of each gas. The relative prices then determine the trade-off between gases at each point in time, taking into account economical as well as physical considerations. Our analysis shows that the relative prices are sensitive to the lifetime of the gases, the choice of target and the proximity of the target, making short-lived gases more expensive to emit as we approach the prescribed ceiling. PMID:11287950

  16. Gradient anaysis of biomass in Costa Rica and a first estimate of total emissions of greenhouse gases from biomass burning

    SciTech Connect

    Helmer, E.H.; Brown, S.

    1997-12-31

    One important component of sustainable development for a nation is the degree to which it can balance greenhouse gas (GHG) exchange with the atmosphere. Scientists at NHEERL-WED recently estimated the release of such GHGs from the conversion of a range of forest types in Costa Rica between 1940-1983. They also evaluated the influence of environmental gradients that affect the rates and patterns of deforestation and the carbon pools of the forest cleared on GHG emissions.

  17. Imbalance of Nature due to Greenhouse Gases from Land-Use Change and Forestry in the State of Sinaloa, Mexico

    NASA Astrophysics Data System (ADS)

    Guzman Galindo, T. D.; Plata Rocha, W. D.; Aguilar-Villegas, J. M.

    2013-05-01

    The imbalance of nature in recent years has been highlighted throughout the world due to the consequences of population and economic growth and changes land use in general. These changes are the result of complex processes between the human and natural environment. This is a very important phenomenon, especially from the point of view of sustainability, as these changes have been considered as one of the most important components of global change (Plata et al., 2009). In the same way the process of deforestation and forest degradation as a result of human activities are a major source of emissions of greenhouse gases in Mexico (Masera et al., 1997). However, forests in Mexico have great potential to become carbon sinks by adopting appropriate support policies, and implementation of sustainable forestry management techniques to improve their production. From this perspective, forest management and reforestation of forests are presented as options for short and medium term climate change mitigation (Sheinbaum and Masera, 2000). Based on the foregoing, the research updates emissions from the Land-Cover and Land-Use Change (LCLUC) for the period 2000 to 2005 for the State of Sinaloa, Mexico, from activity data and national emission factors, reliable and updated to improve certainty and to determine the emissions of greenhouse gases for the sector. This paper examines the updated statewide LCLUC inventory using the gradation level 2 of the IPCC and recommends climate change mitigation and adaptation strategies.t;

  18. Investigation of the relationship between atmospheric mercury and concentrations of key greenhouse gases at a mountainous monitoring site.

    PubMed

    Kim, Ki-Hyun; Pandey, Sudhir Kumar; Brown, Richard J C; Sheu, Guey Rong; Jeon, Eui-Chan; Jung, Kweon; Kang, Chang-Hee

    2015-03-01

    The concentration of total gaseous mercury (TGM) was monitored, together with some key greenhouse gases (GHGs: carbon dioxide (CO2), methane (CH4), and water (H2O) vapor) at hourly intervals at a mountainous monitoring site close to the highly industrialized city of Seoul, Korea. Correlations between the concentrations of Hg and those of the greenhouse gases were examined to assess their source characteristics and responses to changes in meteorological conditions. The mean Hg levels in this study (3.58 ± 2.13 ng m(-3)) were considerably lower (by, e.g., 24.3%) than those measured previously in other comparable sites during 1999-2006 (4.73 ± 1.34 ng m(-3)). Accordingly, such a reduction in Hg levels suggests the effectiveness of the regulatory measures enforced over the years. The mean Hg level observed in this study is also lower (by approximately 5%) than those in other Asian locations. In contrast, the mean concentrations of the two most important GHGs (CO2 and CH4) were moderately higher than those of other locations across the world (by approximately 4-9%). The results of our analysis indicate that the behavior of Hg is strongly correlated with water vapor and CH4 in terms of their source characteristics, despite notable differences in their diurnal patterns. PMID:25639653

  19. Radio Heating of Lunar Soil to Release Gases

    NASA Technical Reports Server (NTRS)

    Chui, Talso; Penanen, Konstantin

    2006-01-01

    A report proposes the development of a system to collect volatile elements and compounds from Lunar soil for use in supporting habitation and processing into rocket fuel. Prior exploratory missions revealed that H2, He, and N2 are present in Lunar soil and there are some indications that water ice may also be present. The proposed system would include a shroud that would be placed on the Lunar surface. Inside the shroud would be a radio antenna aimed downward. The antenna would be excited at a suitably high power and at a frequency chosen to optimize the depth of penetration of radio waves into the soil. The radio waves would heat the soil, thereby releasing volatiles bound to soil particles. The escaping volatiles would be retained by the shroud and collected by condensation in a radiatively cooled vessel connected to the shroud. It has been estimated that through radio-frequency heating at a power of 10 kW for one day, it should be possible to increase the temperature of a soil volume of about 1 cubic m by about 200 C -- an amount that should suffice for harvesting a significant quantity of volatile material.

  20. Data on greenhouse gases emission in condensate separation unit of a petrochemical company in Iran.

    PubMed

    Ahmadi, Mehdi; Dastorian, Mehrshad; Jafarzadeh, Nemat; Jorfi, Sahand; Ramavandi, Bahman

    2016-09-01

    Since global warming due to greenhouse gas emissions is no respecter of geographical boundaries of countries, concerted mitigation activities such as Clean Development Mechanism (CDM), are suitable. In this mechanism, some developed countries can gain certified emission reduction credits from emission reduction actions undertaken in developing countries. Thus, the data of greenhouse gas emissions in developing countries would be informative for implementing of CDM. Herein, the data of greenhouse gas emissions of Bandar Imam Petrochemical Complex, one of the biggest petrochemical companies in the Middle East region is presented. The data was acquired using emission factor method and self-presented raw information of the Bandar Imam Petrochemical Complex. Overall, the data will be interesting for environmentalists, non-governmental organization (NGO), and developed countries to perform CDM. PMID:27500190

  1. Effects of water-saving irrigation on emissions of greenhouse gases and prokaryotic communities in rice paddy soil.

    PubMed

    Ahn, Jae-Hyung; Choi, Min-Young; Kim, Byung-Yong; Lee, Jong-Sik; Song, Jaekyeong; Kim, Gun-Yeob; Weon, Hang-Yeon

    2014-08-01

    The effects of water-saving irrigation on emissions of greenhouse gases and soil prokaryotic communities were investigated in an experimental rice field. The water layer was kept at 1-2 cm in the water-saving (WS) irrigation treatment and at 6 cm in the continuous flooding (CF) irrigation treatment. WS irrigation decreased CH(4) emissions by 78 % and increased N(2)O emissions by 533 %, resulting in 78 % reduction of global warming potential compared to the CF irrigation. WS irrigation did not affect the abundance or phylogenetic distribution of bacterial/archaeal 16S rRNA genes and the abundance of bacterial/archaeal 16S rRNAs. The transcript abundance of CH(4) emission-related genes generally followed CH(4) emission patterns, but the difference in abundance between mcrA transcripts and amoA/pmoA transcripts best described the differences in CH(4) emissions between the two irrigation practices. WS irrigation increased the relative abundance of 16S rRNAs and functional gene transcripts associated with Anaeromyxobacter and Methylocystis spp., suggesting that their activities might be important in emissions of the greenhouse gases. The N(2)O emission patterns were not reflected in the abundance of N(2)O emission-related genes and transcripts. We showed that the alternative irrigation practice was effective for mitigating greenhouse gas emissions from rice fields and that it did not affect the overall size and structure of the soil prokaryotic community but did affect the activity of some groups. PMID:24682309

  2. Shipboard monitoring of non-CO2 greenhouse gases in Asia and Oceania using commercially cargo vessels

    NASA Astrophysics Data System (ADS)

    Nara, H.; Tanimoto, H.; Mukai, H.; Nojiri, Y.; Tohjima, Y.; Machida, T.; Hashimoto, S.

    2011-12-01

    The National Institute for Environmental Studies (NIES) has been performing a long-term program for monitoring trace gases of atmospheric importance over the Pacific Ocean since 1995. The NIES Voluntary Observing Ships (NIES-VOS) program currently makes use of commercial cargo vessels because they operate regularly over fixed routes for long periods and sail over a wide area between various ports (e.g., between Japan and the United States, between Japan and Australia/New Zealand, and between Japan and southeast Asia). This program allows systematic and continuous measurements of non-CO2 greenhouse gases, providing long-term datasets for background air over the Pacific Ocean and regionally polluted air around east Asia. We observe both long-lived greenhouse gases (e.g., carbon dioxide) and short-lived air pollutants (e.g., tropospheric ozone, carbon monoxide) on a continuous basis. Flask samples are collected for later laboratory analysis of carbon dioxide, methane, nitrous oxide, and carbon monoxide by using gas chromatographic techniques. In addition, we recently installed cavity ringdown spectrometers for high-resolution measurement of methane and carbon dioxide to capture their highly variable features in regionally polluted air around southeast Asia (e.g., Hong Kong, Thailand, Singapore, Malaysia, Indonesia and Philippine), which is now thought to be a large source due to expanding socioeconomic activities as well as biomass burnings. Contrasting the Japan-Australia/New Zealand and Japan-southeast Asia cruises revealed regional characteristics of sources and sinks of these atmospherically important species, suggesting the existence of additional sources for methane, nitrous oxides, and carbon monoxide in this tropical Asian region.

  3. Influence of Meteorology and interrelationship with greenhouse gases (CO2 and CH4) at a suburban site of India

    NASA Astrophysics Data System (ADS)

    Sreenivas, Gaddamidi; Mahesh, Pathakoti; Subin, Jose; Lakshmi Kanchana, Asuri; Venkata Narasimha Rao, Pamaraju; Dadhwal, Vinay Kumar

    2016-03-01

    Atmospheric greenhouse gases (GHGs), such as carbon dioxide (CO2) and methane (CH4), are important climate forcing agents due to their significant impacts on the climate system. The present study brings out first continuous measurements of atmospheric GHGs using high-precision LGR-GGA over Shadnagar, a suburban site of Central India during the year 2014. The annual mean CO2 and CH4 over the study region are found to be 394 ± 2.92 and 1.92 ± 0.07 ppm (μ ± 1σ) respectively. CO2 and CH4 show a significant seasonal variation during the study period with maximum (minimum) CO2 observed during pre-monsoon (monsoon), while CH4 recorded the maximum during post-monsoon and minimum during monsoon. Irrespective of the seasons, consistent diurnal variations of these gases are observed. Influences of prevailing meteorology (air temperature, wind speed, wind direction, and relative humidity) on GHGs have also been investigated. CO2 and CH4 show a strong positive correlation during winter, pre-monsoon, monsoon, and post-monsoon with correlation coefficients (Rs) equal to 0.80, 0.80, 0.61, and 0.72 respectively, indicating a common anthropogenic source for these gases. Analysis of this study reveals the major sources for CO2 are soil respiration and anthropogenic emissions while vegetation acts as a main sink, whereas the major source and sink for CH4 are vegetation and presence of hydroxyl (OH) radicals.

  4. Effect of cover crop in mitigation of greenhouse gases emission from plots amended with swine manure

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Greenhouse gas emissions nitrous oxide, carbon dioxide, and methane (N2O, CO2 and CH4,) were measured from corn-soybean plots amended with different rates of liquid swine manure, and in the presence or absence of a rye winter cover crop. Emission measurements include two periods: 1) from October 20...

  5. Life-cycle analysis of dryland greenhouse gases affected by cropping sequence and nitrogen fertilization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Little information is available about management practices effect on net global warming potential (GWP) and greenhouse gas intensity (GHGI) under dryland cropping systems. We evaluated the effects of cropping sequences (conventional till malt barley-fallow [CTB-F], no-till malt barley-pea [NTB-P], a...

  6. 76 FR 59542 - Mandatory Reporting of Greenhouse Gases: Changes to Provisions for Electronics Manufacturing To...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-27

    ... Removal Efficiency. EPA U.S. Environmental Protection Agency. FR Federal Register. GHG greenhouse gas. ICR...) (75 FR 74774) (subpart I). In that rule, among other provisions, EPA finalized two different methods... BAMM, from June 30, 2011 to September 30, 2011 (76 FR 36339). Second, also on June 22, 2011,...

  7. 76 FR 36472 - Mandatory Reporting of Greenhouse Gases; Changes to Provisions for Electronics Manufacturing...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-22

    ... EPA U.S. Environmental Protection Agency FR Federal Register GHG greenhouse gas m\\2\\ square meters mm... emission sources and suppliers in the United States (74 FR 56260). The rule requires annual reporting to... FR 16448) as part of a larger rulemaking effort to establish a GHG reporting program for all...

  8. "An Inconvenient Truth" Increases Knowledge, Concern, and Willingness to Reduce Greenhouse Gases

    ERIC Educational Resources Information Center

    Nolan, Jessica M.

    2010-01-01

    Since May 24, 2006 millions of people have seen the movie "An Inconvenient Truth." Several countries have even proposed using the film as an educational tool in school classrooms. However, it is not yet clear that the movie accomplishes its apparent goals of increasing knowledge and concern, and motivating people to reduce their greenhouse gas…

  9. 76 FR 37300 - Mandatory Reporting of Greenhouse Gases: Petroleum and Natural Gas Systems: Revisions to Best...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-27

    ... Protection Agency FR Federal Register GHG greenhouse gas IBR incorporation by reference ICR information... CFR part 98, subpart W (75 FR 74458) (subpart W). Included in the final rule were new provisions that... preamble to the 2009 final rule (74 FR 56260), CAA section 114 provides EPA broad authority to require...

  10. 76 FR 56009 - Mandatory Reporting of Greenhouse Gases: Technical Revisions to the Electronics Manufacturing and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-09

    ... BOEMRE Bureau of Ocean Energy Management, Regulation and Enforcement CAA Clean Air Act CBI confidential... List FERC Federal Energy Regulatory Commission FR Federal Register GHG greenhouse gas GPA Gas... of Air Quality, Planning and Standards OMB Office of Management and Budget PHMSA Pipeline...

  11. Environmental controls of greenhouse gas release in a restoring peat bog in NW Germany

    NASA Astrophysics Data System (ADS)

    Glatzel, S.; Forbrich, I.; Krüger, C.; Lemke, S.; Gerold, G.

    2008-01-01

    In Central Europe, most bogs have a history of drainage and many of them are currently being restored. Success of restoration as well as greenhouse gas exchange of these bogs is influenced by environmental stress factors as drought and atmospheric nitrogen deposition. We determined the methane and nitrous oxide exchange of sites in the strongly decomposed center and less decomposed edge of the Pietzmoor bog in NW Germany in 2004. Also, we examined the methane and nitrous oxide exchange of mesocosms from the center and edge before, during, and following a drainage experiment as well as carbon dioxide release from disturbed unfertilized and nitrogen fertilized surface peat. In the field, methane fluxes ranged from 0 to 3.8 mg m-2 h-1 and were highest from hollows. Field nitrous oxide fluxes ranged from 0 to 574 μg m-2 h-1 and were elevated at the edge. A large Eriophorum vaginatum tussock showed decreasing nitrous oxide release as the season progressed. Drainage of mesocosms decreased methane release to 0, even during rewetting. There was a tendency for a decrease of nitrous oxide release during drainage and for an increase in nitrous oxide release during rewetting. Nitrogen fertilization did not increase decomposition of surface peat. Our examinations suggest a competition between vascular vegetation and denitrifiers for excess nitrogen. We also provide evidence that the von Post humification index can be used to explain greenhouse gas release from bogs, if the role of vascular vegetation is also considered. An assessment of the greenhouse gas release from nitrogen saturated restoring bogs needs to take into account elevated release from fresh Sphagnum peat as well as from sedges growing on decomposed peat. Given the high atmospheric nitrogen deposition, restoration will not be able to achieve an oligotrophic ecosystem in the short term.

  12. Modeling the infrastructure dynamics of China -- Water, agriculture, energy, and greenhouse gases

    SciTech Connect

    Conrad, S.H.; Drennen, T.E.; Engi, D.; Harris, D.L.; Jeppesen, D.M.; Thomas, R.P.

    1998-08-01

    A comprehensive critical infrastructure analysis of the People`s Republic of China was performed to address questions about China`s ability to meet its long-term grain requirements and energy needs and to estimate greenhouse gas emissions in China likely to result from increased agricultural production and energy use. Four dynamic computer simulation models of China`s infrastructures--water, agriculture, energy and greenhouse gas--were developed to simulate, respectively, the hydrologic budgetary processes, grain production and consumption, energy demand, and greenhouse gas emissions in China through 2025. The four models were integrated into a state-of-the-art comprehensive critical infrastructure model for all of China. This integrated model simulates diverse flows of commodities, such as water and greenhouse gas, between the separate models to capture the overall dynamics of the integrated system. The model was used to generate projections of China`s available water resources and expected water use for 10 river drainage regions representing 100% of China`s mean annual runoff and comprising 37 major river basins. These projections were used to develop estimates of the water surpluses and/or deficits in the three end-use sectors--urban, industrial, and agricultural--through the year 2025. Projections of the all-China demand for the three major grains (corn, wheat, and rice), meat, and other (other grains and fruits and vegetables) were also generated. Each geographic region`s share of the all-China grain demand (allocated on the basis of each region`s share of historic grain production) was calculated in order to assess the land and water resources in each region required to meet that demand. Growth in energy use in six historically significant sectors and growth in greenhouse gas loading were projected for all of China.

  13. Controlled Freeze-thaw Experiments to Study Biogeochemical Process and its Effects on Greenhouse Gas Release in Arctic Soil Columns

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Kneafsey, T. J.; Tas, N.; Bill, M.; Ulrich, C.; Hubbard, S. S.

    2014-12-01

    Greenhouse gas release associated with permafrost thawing is one of the largest uncertainties in future climate prediction. Improvement of such prediction relies on a better representation of the interactions between hydrological, geochemical and microbial processes in the Arctic ecosystem that occur over a wide range of space and time scales and under dynamic freeze-thaw conditions. As part of the Next Generation Ecosystem Experiments in the Arctic (NGEE-Arctic), we conducted controlled laboratory freeze-thaw experiments to study greenhouse gas release in vertical permafrost soil columns with vertically heterogeneous hydrological, geochemical and microbial properties. The studies were performed using soil cores collected from the NGEE Barrow, AK site. Two cores collected next to each other with very similar soil structures were used for the experiment. One of the cores was destructively sampled for baseline characterization, and the second core was used for the freeze-thaw experiments. The core extends from the ground surface into the permafrost with roughly 40 cm of active layer. The column was instrumented with various sensors and sampling devices, including thermocouples, geophysical (electrical) sensors, and sampling ports for solids and fluids. The headspace of the soil column was purged with CO2 free air and the gas samples were collected periodically for greenhouse gas analysis. Our initial tests simulated seasonal temperature variation from ~ -10°C to +10°C at the ground surface. Our results demonstrated that temperature and geophysical data provided real time information on the freeze thaw dynamics of the column and the surface greenhouse gas fluxes correlated with the freeze thaw stages and associated hydrological and biogeochemical processes in the vertical soil column. For example, surface fluxes data revealed an early burst of GHG concentrations during the initial thawing of the surface ice rich layer of the soil, indicating the presence of trapped

  14. Air-water greenhouse gases exchange in two coastal systems in Cadiz Bay (SW Spain)

    NASA Astrophysics Data System (ADS)

    Burgos, Macarena; Ortega, Teodora; Forja, Jesús

    2014-05-01

    Coastal areas are subject to a great anthropogenic pressure because more than half of the world's population lives in its vicinity, causing organic matter inputs, which intensifies greenhouse gas emissions into the atmosphere. Water surface greenhouse gas concentrations (CH4 and N2O) have been estimated in two aquatic systems of Cadiz Bay Natural Park: Rio San Pedro Creek and Sancti Petri Channel Water renewal in Rio San Pedro Creek is tidally controlled. Due to its little freshwater input, the Creek is essentially a marine system. Several fish farms are distributed on its banks discharging effluents without previous treatment. Nine sampling stations are distributed along this system 12 Km length. Sancti Petri Channel is a flow channel-ebb tides extending from the inner Cadiz Bay to the Atlantic Ocean along 17 Km. Organic matter pollution sources in this environment are straggly. There exist anthropogenic inputs such as aquaculture effluents and sewage discharges coming through the Iro River, which flows into the Channel central part. In addition there are natural organic matter inputs from surrounding marshes. It has been established 11 sampling stations crossing this system. Sampling was conducted seasonally during 2013. CH4 and N2O concentrations were obtained though a gas chromatograph connected to an equilibration system. Greenhouse gas values vary between 24 and 295 nM and 16 and 27 nM for CH4 and N2O, respectively. Gas concentrations increase close to the fish farm effluent in Rio San Pedro Creek, and next to Iro River's mouth in Sancti Petri tidal Channel. Both environments act as greenhouse gas sources into the atmosphere, showing seasonal variations. It has been estimated mean fluxes of 75.3 μmol m-2 d-1 of CH4 and 31.9 μmol m-2 d-1 of N2O for both systems.

  15. The forcing of anthropogenic aerosols and greenhouse gases on sub-thermocline temperature trends in the southern subtropical Indian Ocean

    NASA Astrophysics Data System (ADS)

    Cowan, T.; Purich, A.; Cai, W.; Rotstayn, L. D.; England, M. H.

    2013-12-01

    In the late twentieth century, the sub-thermocline waters of the southern tropical and subtropical Indian Ocean (IO) experienced a sharp cooling. This cooling has been previously attributed to an anthropogenic aerosol-induced strengthening of the global ocean conveyor, which transfers heat from the subtropical gyre latitudes toward the North Atlantic. From the mid-1990s the sub-thermocline IO experienced a rapid temperature trend reversal. In the context of understanding the causes of the sub-thermocline temperature changes, we use a suite of Coupled Model Intercomparison Project phase 5 (CMIP5) models forced with natural and anthropogenic radiative forcings and as well as individual forcing runs. We use these to: (i) examine whether the sub-thermocline cooling and/or rapid warming of the tropical/subtropical IO is anthropogenic or naturally forced; and (ii) assess future projections of the sub-thermocline temperatures in the mid twenty-first century from available model output. Results suggest that the late twentieth century sub-thermocline cooling of the southern IO was primarily driven by increasing anthropogenic aerosols and greenhouse gases. The models simulate a slow-down in the sub-thermocline cooling followed by a rapid warming towards the middle of the twenty-first century. The timing of the commencement of this warming appears dependent on the total change in anthropogenic aerosol levels, with models exhibiting a strong (weak) decline in future aerosols simulating a greater (weaker) magnitude of warming after the occurrence of peak aerosols. The role of greenhouse gases in forcing sub-thermocline temperature trends in the IO in the future remains to be determined. Despite this, it is clear is that as human generated aerosols continue to decline over the coming century, the subsurface ocean circulation will respond accordingly through an acceleration in the warming.

  16. The early faint sun paradox: organic shielding of ultraviolet-labile greenhouse gases

    NASA Technical Reports Server (NTRS)

    Sagan, C.; Chyba, C.

    1997-01-01

    Atmospheric mixing ratios of approximately 10(-5 +/- 1) for ammonia on the early Earth would have been sufficient, through the resulting greenhouse warming, to counteract the temperature effects of the faint early sun. One argument against such model atmospheres has been the short time scale for ammonia photodissociation by solar ultraviolet light. Here it is shown that ultraviolet absorption by steady-state amounts of high-altitude organic solids produced from methane photolysis may have shielded ammonia sufficiently that ammonia resupply rates were able to maintain surface temperatures above freezing.

  17. Effect of duckweed cover on greenhouse gas emissions and odour release from waste stabilisation ponds.

    PubMed

    van der Steen, N P; Nakiboneka, P; Mangalika, L; Ferrer, A V M; Gijzen, H J

    2003-01-01

    Treatment of wastewater in stabilisation pond systems prevents the negative environmental impact of uncontrolled disposal of sewage. However, even a natural treatment system may generate secondary negative environmental impacts in terms of energy consumption, emission of greenhouse gases and emission of odorous compounds. Whereas natural systems have an advantage over electro-mechanical systems in that they use less hardware and less energy, it is not yet known whether secondary environmental effects in the form of greenhouse gas emissions are lower for these systems. This research intends to be a first step in the direction of answering this question by assessing gas emissions from two types of natural systems, namely algae-based and duckweed-based stabilisation ponds. The H2S volatilisation from laboratory scale pond-reactors has been determined by drawing the air above the water surface continuously through a solution of 1 M NaOH for absorption of sulphide. The amount of H2S that volatilised from the algae pond-reactor, and was trapped in the NaOH trap, was found to be 2.5-86 mg/m2/day. The H2S volatilisation from the duckweed pond-reactor was found to be negligible, even though the sulphide concentration was 9.7 mg/l S(2-). The duckweed cover was a physical barrier for volatilisation, since bubbles were trapped in the cover. In addition the duckweed layer was found to be afavourable environment for both aerobic sulphide oxidisers (Beggiatoa gigantae) as well as for photosynthetic purple sulphur bacteria belonging to the genus Chromatium. These may also have contributed to the prevention of H2S volatilisation. Results on methane emissions were not conclusive so far, but the same mechanisms that prevent H2S volatilisation may also prevent methane volatilisation. Therefore it was concluded that duckweed covers on stabilisation ponds may reduce the emission of both odorous and greenhouse gases. PMID:14510229

  18. Detection of optical path in spectroscopic space-based observations of greenhouse gases: Application to GOSAT data processing

    NASA Astrophysics Data System (ADS)

    Oshchepkov, Sergey; Bril, Andrey; Maksyutov, Shamil; Yokota, Tatsuya

    2011-07-01

    We present a method to detect optical path modification due to atmospheric light scattering in space-based greenhouse gas spectroscopic sounding. This method, which was applied to the analysis of radiance spectra measured by the Greenhouse Gases Observing Satellite (GOSAT), is based on the path length probability density function (PPDF) and on retrieval of PPDF parameters from radiance spectra in the oxygen A-band of absorption at 0.76 μm. We show that these parameters can be effectively used to characterize the impact of atmospheric light scattering on carbon dioxide retrieval in the atmospheric carbon dioxide (CO2) absorption bands at 1.6 μm and 2.0 μm. The threshold for PPDF parameters is set so that the optical-path modification is negligible, and these settings are recommended as a basic guideline for selecting the clearest atmospheric scenarios. An example of data processing for six global GOSAT repeat cycles in April and July 2009 shows that PPDF-based selection efficiently removes CO2 retrieval biases associated with subvisible cirrus and sandstorm activities.

  19. On the role of atmosphere-ocean interactions in the expected long-term changes of the Earth's ozone layer caused by greenhouse gases

    NASA Astrophysics Data System (ADS)

    Zadorozhny, Alexander; Dyominov, Igor

    It is well known that anthropogenic emissions of greenhouse gases into the atmosphere produce a global warming of the troposphere and a global cooling of the stratosphere. The expected stratospheric cooling essentially influences the ozone layer via increased polar stratospheric cloud formation and via temperature dependences of the gas phase reaction rates. One more mechanism of how greenhouse gases influences the ozone layer is enhanced water evaporation from the oceans into the atmosphere because of increasing temperatures of the ocean surface due to greenhouse effect. The subject of this paper is a study of the influence of anthropogenic pollution of the atmosphere by the greenhouse gases CO2, CH4, N2O and ozone-depleting chlorine and bromine compounds on the expected long-term changes of the ozone layer with taking into account an increase of water vapour content in the atmosphere due to greenhouse effect. The study based on 2-D zonally averaged interactive dynamical radiative-photochemical model of the troposphere and stratosphere. The model allows to self-consistently calculating diabatic circulation, temperature, gaseous composition of the troposphere and stratosphere at latitudes from the South to North Poles, as well as distribution of sulphate aerosol particles and polar stratospheric clouds of two types. It was supposed in the model that an increase of the ocean surface temperature caused by greenhouse effect is similar to calculated increase of atmospheric surface temperature. Evaporation rate from the ocean surface was computed in dependence of latitude. The model time-dependent runs were made for the period from 1975 to 2100 using two IPCC scenarios depicting maximum and average expected increases of greenhouse gases in the atmosphere. The model calculations show that anthropogenic increasing of water vapour abundance in the atmosphere due to heating of the ocean surface caused by greenhouse effect gives a sensible contribution to the expected ozone

  20. Cattle feedlot soil moisture and manure content: I. Impacts on greenhouse gases, odor compounds, nitrogen losses, and dust.

    PubMed

    Miller, Daniel N; Berry, Elaine D

    2005-01-01

    Beef cattle feedlots face serious environmental challenges associated with manure management, including greenhouse gas, odor, NH3, and dust emissions. Conditions affecting emissions are poorly characterized, but likely relate to the variability of feedlot surface moisture and manure contents, which affect microbial processes. Odor compounds, greenhouse gases, nitrogen losses, and dust potential were monitored at six moisture contents (0.11, 0.25, 0.43, 0.67, 1.00, and 1.50 g H2O g(-1) dry matter [DM]) in three artificial feedlot soil mixtures containing 50, 250, and 750 g manure kg(-1) total (manure + soil) DM over a two-week period. Moisture addition produced three microbial metabolisms: inactive, aerobic, and fermentative at low, moderate, and high moisture, respectively. Manure content acted to modulate the effect of moisture and enhanced some microbial processes. Greenhouse gas (CO2, N2O, and CH4) emissions were dynamic at moderate to high moisture. Malodorous volatile fatty acid (VFA) compounds did not accumulate in any treatments, but their persistence and volatility varied depending on pH and aerobic metabolism. Starch was the dominant substrate fueling both aerobic and fermentative metabolism. Nitrogen losses were observed in all metabolically active treatments; however, there was evidence for limited microbial nitrogen uptake. Finally, potential dust production was observed below defined moisture thresholds, which were related to manure content of the soil. Managing feedlot surface moisture within a narrow moisture range (0.2-0.4 g H2O g(-1) DM) and minimizing the accumulation of manure produced the optimum conditions that minimized the environmental impact from cattle feedlot production. PMID:15758117

  1. Evaluation of the generation and release of flammable gases in tank 241-SY-101

    SciTech Connect

    Babad, H.; Johnson, G.D.; Lechelt, J.A.; Reynolds, D.A. ); Pederson, L.R.; Strachan, D.M. ); Meisel, D.; Jonah, C. ); Ashby, E.C. )

    1991-11-01

    Tank 241-SY-101 is a double shell, high-level waste tank located in the 200 West Area of the Hanford Site. This tank contains about 1 million gallons of waste that was concentrated at the 242-S Evaporator. Shortly after the waste was put in the tank, the waste began to expand because the generation of gases. In 1990 this tank was declared to have an unreviewed safety question because of the periodic release of hydrogen and nitrous oxide. A safety program was established to conduct a characterization of the waste and vented gases and to determine an effective means to prevent the accumulation of flammable gases in the tank dome space and ventilation system. Results of the expanded characterization conducted in fiscal year 1991 are presented. The use of gas chromatographs, mass spectrometers, and hydrogen-specific monitors provided a greater understanding of the vented gases. Additional instrumentation placed in the tank also helped to provide more detailed information on tank temperatures, gas pressure, and gas flow rates. An extensive laboratory study involving the Westinghouse Hanford Company, Pacific Northwest Laboratory, Argonne National Laboratory, and the Georgia Institute of Technology was initiated for the purpose of determining the mechanisms responsible for the generation of various gases. These studies evaluate both radiolytic and thermochemical processes. Results of the first series of experiments are described.

  2. Emissions of greenhouse gases, ammonia, and hydrogen sulfide from pigs fed standard diets and diets supplemented with dried distillers grains with solubles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Swine growers are increasingly supplementing animal diets with dried distillers grains soluble (DDGS) to offset cost of a typical corn-soybean meal diet. An experiment was conducted to investigate the effects of DDGS diets on both on manure composition and emissions of greenhouse gases (GHG), ammoni...

  3. Simulations of greenhouse trace gases using the Los Alamos chemical tracer model

    SciTech Connect

    Kao, C.Y.J.; Morz, E. ); Tie, X. )

    1991-11-01

    Through three-dimensional global model studies on atmospheric composition and transport, we are improving our quantitative understanding of the origins and behavior of trace gases that affect Earth's radiative energy balance and climate. We will focus, in this paper, on the simulations of three individual trace gases including CFC-11, methyl chloroform, and methane. We first used our chemical tracer model to study the global distribution and trend of chemically inert CFC-11 observed by the Atmospheric Lifetime Experiment. The results show that the model has the ability to reproduce the time-series of the observations. The purpose of this CFC-11 simulation was to test the transport of the model. We then used to model introduce methyl chloroform into the atmosphere according to the known emission patterns and iteratively varied OH fields so that the observed concentrations of methyl chloroform from the observations could be simulated well. The rationale behind this approach is that the reaction with OH is the dominant sink for metyl chloroform and the transport of the model has been tested in the previous CFC-11 study. Finally, using the inferred OH distributions, we conducted a steady-state simulation to reproduce the current methane distribution. The general agreement between the modeled an observed methane surface concentrations has laid a foundation for the simulation of the transient increase of methane.

  4. Simulations of greenhouse trace gases using the Los Alamos chemical tracer model

    SciTech Connect

    Kao, C.Y.J.; Morz, E.; Tie, X.

    1991-11-01

    Through three-dimensional global model studies on atmospheric composition and transport, we are improving our quantitative understanding of the origins and behavior of trace gases that affect Earth`s radiative energy balance and climate. We will focus, in this paper, on the simulations of three individual trace gases including CFC-11, methyl chloroform, and methane. We first used our chemical tracer model to study the global distribution and trend of chemically inert CFC-11 observed by the Atmospheric Lifetime Experiment. The results show that the model has the ability to reproduce the time-series of the observations. The purpose of this CFC-11 simulation was to test the transport of the model. We then used to model introduce methyl chloroform into the atmosphere according to the known emission patterns and iteratively varied OH fields so that the observed concentrations of methyl chloroform from the observations could be simulated well. The rationale behind this approach is that the reaction with OH is the dominant sink for metyl chloroform and the transport of the model has been tested in the previous CFC-11 study. Finally, using the inferred OH distributions, we conducted a steady-state simulation to reproduce the current methane distribution. The general agreement between the modeled an observed methane surface concentrations has laid a foundation for the simulation of the transient increase of methane.

  5. Emission Factors of Greenhouse Gases and Particulates from Australian Savanna Fires

    NASA Astrophysics Data System (ADS)

    Desservettaz, Maximilien; Paton-Walsh, Clare; Griffith, David; Kettlewell, Graham; Wilson, Stephen; Keywood, Melita; Van der Schoot, Marcel; Seleck, Paul; Ward, Jason; Harwell, James; Reisen, Fabienne; Lawson, Sarah; Ristovski, Zoran; Mallet, Marc; Miljevic, Brenka; Milic, Andjelija; Atkinson, Brad

    2016-04-01

    In June 2014 a measurement campaign took place at the Australian Tropical Atmospheric Research Station (ATARS), in the Northern Territory, Australia, during the early dry season. The campaign was focused on understanding biomass burning emissions from savanna fires. In order to achieve this, a suite of aerosol, reactive and trace gases instruments were deployed. Seven smoke events were extracted from the 4 weeks of continuous measurements using carbon monoxide as a proxy for biomass burning. Those events were then analysed and emission factors were calculated for CO2, CO, CH4, N2O, NOx and aerosols (Aitken and Accumulation mode, and chemical speciation), along with the modified combustion efficiency (MCE). Upon review of the emission factors, smoke events could then be classified in 3 groups: high MCE events (0.98) were characterised by emission factors typical of savanna grass fires while low MCE events (0.88) were characteristic of shrub fires. Intermediate MCE events (0.93) were found not to reflect any distinct vegetation type. This presentation will outline the campaign and present emission factors of trace and reactive gases as well as the first emission factors for aerosols reported for Australian savanna fires.

  6. Ionic composition and greenhouse gases evaluation in Tietê River sediment and mud landfill

    NASA Astrophysics Data System (ADS)

    La-Scalea, M. A.; Fornaro, A.; Abreu, E. L.; Mendonça, C. A.

    2012-04-01

    There are 39 cities composing the Metropolitan Area of São Paulo (MASP) which has grown seven times during the last sixty years, reaching, in 2011, 19.3 million inhabitants. This fact associated with a strong industrial development provoked, among other consequences, a disordered urbanization along the most important river of the region: Tietê. About 100 Km of its 1,150 Km full extension crosses MASP and, during the 60's, Marginal Tietê roadway was constructed, occupying the river banks as access routes. Tietê River was straightened and several landfills were created with its deposit (sediment and mud). EACH-USP (46.50 W, 23.48 S) lies nowadays in one of these areas, where this work has been developed. Therefore, the goal is to evaluate the chemical composition (ionic and gases) and its variability in function of the depth levels using three wells, from 0.60 to 9.0 m of depth. The wells were perforated in September 2011, end of the dry weather. Each well owns a homemade multiport sampling device (HMSD), being possible to push gas and/or water up from 15 available ports. The gases measurements were carried out using a GEM-2000 plus (Landtec) portable analyzer. Aqueous samples containing solid material were taken at each level depth from ports of the HMSD. However, no water was found in some levels. All samples were kept cooled until analysis procedures. After decantation of the solid material, the supernatant liquid was divided in two portions, being its conductivity (Micronal conductimeter) and pH (pH-meter Metrohm 654 with combined glass electrode) measured with the former and ionic analysis with the latter, in which all samples were filtered (Millex 0.22 micrometer pores) before each ionic chromatographic analysis, using Metrohm 850 System, for the ions: sodium, ammonium, potassium, calcium, magnesium, chloride, nitrate and sulfate. The first sampling stage was carried out during November and December 2011 in the beginning of rainy season in the mid Spring

  7. Greenhouse Gases in the South Atlantic: Testing and Automation of Instrumentation for Long-Term Monitoring

    NASA Astrophysics Data System (ADS)

    Lowry, D.; Fisher, R.; Sriskantharajah, S.; Lanoisellé, M.; Etchells, A.; Manning, A.; Nisbet, E.

    2009-04-01

    Understanding ocean uptake of atmospheric CO2 by the Southern Ocean is important for modelling of future global warming scenarios, particularly since it was recently proposed that this sink was reducing (Le Quéré, et al., 2007). To help our understanding of this problem a new project aims to flask sample air from 5 South Atlantic sites and set up continuous monitoring at the 2 most accessible of these: Ascension Island and the Falklands. Flask sample measurements will include CO2 and CH4 mixing ratios and the ^13C measurement of both of these gases using the rapid continuous flow trace gas analysis system at Royal Holloway, University of London (RHUL). Routine precisions are ±0.03 per mil and ±0.05 per mil for CO2 and CH4, respectively (Fisher et al., 2006). A time series of ^13C in CH4 was maintained for Ascension Island from 2000-2005 and a time series for methane isotopes commenced for the Falkland Islands in autumn 2007. To meet the continuous monitoring requirements of the new project, three Picarro G1301 CO2 / CH4 / H2O Cavity Ring Down Spectrometers (CRDS) were installed at RHUL in October 2008 for testing, calibration and the development of an automated air inlet system suitable for analysis of calibration gases at the remote sites. Initial testing included calibration with NOAA calibrated and target gases, validation of the Picarro-defined H2O-correction of CO2, and derivation of an H2O-correction for CH4. Continuing checks on the H2O correction are made by having 2 instruments side-by-side taking air from the same inlet, but one having a combined Nafion / Mg-perchlorate drying system that utilizes the analysis system exhaust gas for the reverse flow through the Nafion and maintains water-levels at 0.05% for more than 2 weeks. These instruments are connected to the same air inlet as a GC measuring CH4 mixing ratio and a LiCor 6252 measuring CO2 mixing ratio at 30-minute and 1-minute intervals respectively. The third CRDS instrument is connected to a

  8. The Role of Non-CO2 Greenhouse Gases and Aerosols in Climate Mitigation

    SciTech Connect

    Smith, Steven J.; Bond, Tami C.; Wigley, Tom M.; de la Chesnaye, Francisco; Pitcher, Hugh M.

    2003-11-17

    Forcing agents other than carbon dioxide, such as methane, nitrous oxide, halocarbons, and perhaps aerosol particles, may play a major role in mitigating climate change. Of these agents, methane is the most important greenhouse gas and has substantial mitigation potential. The role of black and organic carbon aerosols has attracted increasing interest and we explicitly include these carbonaceous aerosols in our calculations. This paper analyzes the potential role of different forcing agents in reducing future climate forcing in a multi-gas, integrated assessment model in which mitigation options compete and interact. Our framework includes all of the important atmospheric forcing agents: carbon dioxide, methane, nitrous oxide, halocarbons, sulfur dioxide, and carbonaceous aerosols along with an array of potential mitigation options. Through an integrated analysis of all available options we present a realistic portrait of the potential role of these forcing agents in limiting future climate change.

  9. Economic feasibility study for intensive and extensive wastewater treatment considering greenhouse gases emissions.

    PubMed

    Molinos-Senante, M; Hernández-Sancho, F; Sala-Garrido, R; Cirelli, G

    2013-07-15

    Economic feasibility assessments represent a key issue for selecting which wastewater treatment processes should be implemented. The few applications that exist focus on the positive economic value of externalities, overlooking the existence of negative externalities. However, wastewater treatment plants (WWTPs) consume a significant amount of energy, contributing to climate change. In this context, as a pioneering approach, greenhouse gas emissions (GHG) have been incorporated as a negative externality of wastewater treatment. Within this framework, this study aims to compare the economic feasibility of five technologies, both intensive and extensive, for small communities. The results show that both the investment and operation costs are higher for intensive than for extensive technologies. Moreover, significant differences in the value of negative externalities were observed. This study demonstrates that from an economic perspective, constructed wetland is the most suitable option for treating wastewater in small agglomerations. PMID:23583870

  10. The relative contribution of orbital forcing and greenhouse gases to the North American deglaciation

    NASA Astrophysics Data System (ADS)

    Gregoire, Lauren J.; Valdes, Paul J.; Payne, Antony J.

    2015-11-01

    Understanding what drove Northern Hemisphere ice sheet melt during the last deglaciation (21-7 ka) can help constrain how sensitive contemporary ice sheets are to greenhouse gas (GHGs) changes. The roles of orbital forcing and GHGs in the deglaciation have previously been modeled but not yet quantified. Here for the first time we calculate the relative effect of these forcings on the North American deglaciation by driving a dynamical ice sheet model (GLIMMER-CISM) with a set of unaccelerated transient deglacial simulations with a full primitive equation-based ocean-atmosphere general circulation model (FAMOUS). We find that by 9 ka, orbital forcing has caused 50% of the deglaciation, GHG 30%, and the interaction between the two 20%. Orbital forcing starts affecting the ice volume at 19 ka, 2000 years before CO2 starts increasing in our experiments, a delay which partly controls their relative effect.

  11. CLAIRE: a Canadian Small Satellite Mission for Measurement of Greenhouse Gases

    NASA Astrophysics Data System (ADS)

    Sloan, James; Grant, Cordell; Germain, Stephane; Durak, Berke; McKeever, Jason; Latendresse, Vincent

    2016-07-01

    CLAIRE, a Canadian mission operated by GHGSat Inc. of Montreal, is the world's first satellite designed to measure greenhouse gas emissions from single targeted industrial facilities. Claire was launched earlier this year into a 500 km polar sun-synchronous orbit selected to provide an acceptable balance between return frequency and spatial resolution. Extensive simulations of oil & gas facilities, power plants, hydro reservoirs and even animal feedlots were used to predict the mission performance. The principal goal is to measure the emission rates of carbon dioxide and methane from selected targets with greater precision and lower cost than ground-based alternatives. CLAIRE will measure sources having surface areas less than 10 x 10 km2 with a spatial resolution better than 50 m, thereby providing industrial site operators and government regulators with the information they need to understand, manage and ultimately to reduce greenhouse gas emissions more economically. The sensor is based on a Fabry-Perot interferometer, coupled with a 2D InGaAs focal plane array operating in the short-wave infrared with a spectral resolution of about 0.1 nm. The patented, high étendue, instrument design provides signal to noise ratios that permit quantification of emission rates with accuracies adequate for most regulatory reporting thresholds. The very high spatial resolution of the density maps produced by the CLAIRE mission resolves plume shapes and emitter locations so that advanced dispersion models can derive accurate emission rates of multiple sources within the field of view. The satellite bus, provided by the University of Toronto's Space Flight Laboratory, is based on the well-characterized NEMO architecture, including hardware that has significant spaceflight heritage. The mission is currently undergoing initial test and validation measurements in preparation for commercial operation later this year.

  12. Increased spring flooding of agricultural fields will exhibit altered production of greenhouse gases

    NASA Astrophysics Data System (ADS)

    Paul, R. F.; Smith, C. M.; Smyth, E. M.; Kantola, I. B.; DeLucia, E. H.

    2013-12-01

    The U.S. Corn Belt currently is a net source of carbon dioxide and nitrous oxide to the atmosphere, but is also a sink of methane. Among the proposed effects of climate change in the North American Midwest region is an increase in the frequency and duration of spring flooding events. This would cause ponding in fields which may change the greenhouse gas balance of the region, especially by providing a suitable anoxic environment for the proliferation of methanogens, increasing methane emissions. To determine whether methanogenesis occurs in flooded agricultural soils of the Midwest and how other gas fluxes are affected, we installed collars into the ground of a research field located in central Illinois. The control group was maintained at the same conditions as the surrounding field. Two groups of collars were sustained with water flooding the headspaces via a drip irrigation system; one treatment was analyzed for gas fluxes of CH4, N2O, and CO2 evolving from the collars, and a separate treatment of flooded collars was used for soil sampling. Comparing flooded soils versus control we measured reduced N2O fluxes (-3.12 x 10-6 × 6.8 x 10-7 g N m-2 min-1), reduced CO2 fluxes (-6.13 x 10-3 × 9.3 x 10-4 g CO2 m-2 min-1), and increased methane fluxes (+2.72 x 10-6 × 5.8 x 10-7 g CH4 m-2 min-1). After only one week of treatment the flooded soils switched from being sinks to sources of methane, which continued across the duration of the experiment. These preliminary results indicate that methanogenesis occurs in flooded agricultural fields, and suggest including regional modeling into further study. Although the global warming potential of methane is 25 times greater than CO2, our measured rates of methane production were compensated by reductions in nitrous oxide and CO2 fluxes, reducing the total 100-year horizon global warming potential of the flooded soils we studied by 64.8%. This indicates that accounting for more frequent seasonal ponding would significantly

  13. Modelling of accidental released toxic gases for emergency responders in Austria, Kosovo and Bulgaria.

    NASA Astrophysics Data System (ADS)

    Stenzel, Sirma; Baumann-Stanzer, Kathrin; Gashi, Salih; Thaci, Bashkim; Batchvarova, Ekaterina; Spassova, Tatiana

    2010-05-01

    In the case of accidental release of hazardous gases in the atmosphere, the emergency responders need a reliable and fast tool to assess the possible consequences and apply the optimal countermeasures. A number of models for the prediction and simulation of hazard areas affected by accidental releases of toxic gases are available worldwide. Modelling accidental releases may be required for a variety of reasons: for analyzing different accidental toxic release scenarios ("worst-case scenarios"), for preparing emergency response plans and optimal countermeasures as well as for real-time risk assessment and management (e.g. in the frame of the SEVESO directive). Depending on the demand and the particular purposes, the choice of the appropriate model is up to the authorities. The one year project was funded by the Austrian Science and research liaison Office (ASO, www.aso.zsi.at) as a part of the program: Research Cooperation and Networking between Austria, the public higher education institutions in Kosovo and South Eastern Europe. The project was conducted by the Central Institute for Meteorology and Geodynamics (ZAMG, http://www.zamg.ac.at) in cooperation with the University of Prishtina (Kosovo, www.uni-pr.edu and the National Institute of meteorology and Hydrology (NIHM Bulgaria, www.meteo.bg). One of the main purposes of the project was to provide the both partners with basic knowledge in modelling with accidental release of toxic gases, based on the practical experience of the meteorologists from the ZAMG in the area. This knowledge can be used as scientific response to society driven current or upcoming problems especially in Kosovo. The activities involved know-how transfer on European standards and practice among the project partners, as well as joint efforts to adapt and disseminate the scientific methods and results in Kosovo. Within the project, the partners from Kosovo and Bulgaria were introduced to the atmospheric dispersion model (ALOHA - Areal

  14. Greenhouse gases and other airborne pollutants from household stoves in China: a database for emission factors

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Smith, K. R.; Ma, Y.; Ye, S.; Jiang, F.; Qi, W.; Liu, P.; Khalil, M. A. K.; Rasmussen, R. A.; Thorneloe, S. A.

    Emissions from household stoves, especially those using solid fuels, can contribute significantly to greenhouse gas (GHG) inventories and have adverse health impacts. Few data are available on emissions from the numerous types of cookstoves used in developing countries. We have systematically measured emissions from 56 fuel/stove combinations in India and China, a large fraction of the combinations in use world-wide. A database was generated containing emission factors of direct and indirect GHGs and other airborne pollutants such as CO 2, CO, CH 4, TNMHC, N 2O, SO 2, NO x, TSP, etc. In this paper, we report on the 28 fuel/stove combinations tested in China. Since fuel and stove parameters were measured simultaneously along with the emissions, the database allows construction of complete carbon balances and analyses of the trade-off of emissions per unit fuel mass and emissions per delivered energy. Results from the analyses show that the total emissions per unit delivered energy were substantially greater from burning the solid fuels than from burning the liquid or gaseous fuels, due to lower thermal and combustion efficiencies for solid-fuel/stove combinations. For a given biomass fuel type, increasing overall stove efficiency tends to increase emissions of products of incomplete combustion. Biomass fuels are typically burned with substantial production of non-CO 2 GHGs with greater radiative forcing, indicating that biomass fuels have the potential to produce net global warming commitments even when grown renewably.

  15. The seasonal variation of emission of greenhouse gases from a full-scale sewage treatment plant.

    PubMed

    Masuda, Shuhei; Suzuki, Shunsuke; Sano, Itsumi; Li, Yu-You; Nishimura, Osamu

    2015-12-01

    The seasonal variety of greenhouse gas (GHGs) emissions and the main emission source in a sewage treatment plant were investigated. The emission coefficient to treated wastewater was 291gCO2m(-3). The main source of GHGs was CO2 from the consumption of electricity, nitrous oxide from the sludge incineration process, and methane from the water treatment process. They accounted for 43.4%, 41.7% and 8.3% of the total amount of GHGs emissions, respectively. The amount of methane was plotted as a function of water temperature ranging between 13.3 and 27.3°C. An aeration tank was the main source of methane emission from all the units. Almost all the methane was emitted from the aeration tank, which accounted for 86.4% of the total gaseous methane emission. However, 18.4% of the methane was produced in sewage lines, 15.4% in the primary sedimentation tank, and 60.0% in the aeration tank. PMID:25439128

  16. Prospects of and requirements for nuclear power as a contributor toward managing greenhouse gases

    SciTech Connect

    Hassberger, J.A., Schock, R.N.; Isaacs, T.H.

    1997-10-23

    The world`s population, energy demand, and rate of carbon emissions are increasing, but the rates of increase are uncertain. Even modest growth rates present significant challenges to existing and developing technologies for reducing carbon and greenhouse gas emissions while meeting growing energy demands. Nuclear power is currently the most developed alternative to fossil fuel combustion and is one of the options for meeting these challenges. However, there remain significant technical, economic and institutional barriers inhibiting growth of nuclear capacity in the U.S. and slowing implementation worldwide. In the near-term, the major barriers to nuclear power, especially in the U.S., appear to be economic and institutional, with the risks such as safety, waste management and proliferation having reasonably acceptable limits considering the current installed capacity. Future growth of nuclear power, however, may well hinge on continuous evolutionary and perhaps revolutionary reduction of these risks such that the overall risk of nuclear power, aggregated over the entire installed capacity, remains at or below today`s risks.

  17. TREATMENT PERFORMANCE OF A COMBINED CONSTRUCTED WETLAND SYSTEM AND ITS GREENHOUSE GASES EMISSION

    NASA Astrophysics Data System (ADS)

    Xu, K. Q.; Liu, C.; Ebie, Y.; Inamori, Y.

    2009-12-01

    Constructed wetlands (CWs) can be classified into three typical types: Vertical flow (VF), Free-water Surface (FWS) and Subsurface Flow (SF) CWs according to their structures and directions of water flow. A combined FWS-VF-SFS CW system was designed and built to promote its treatment performance for actual domestic wastewater and reduce greenhouse gas emissions. The results from the pilot-scale combined system indicated that comparatively good performance for pollutant removal, which was 98.5%, 95.9%, 93.2% and 90.7% for BOD5, SS, NH4-N and TP under 6-day HRT, respectively. It was also found that the N2O emission was mainly from the VF unit of the system, which accounted for more than 80% of the total emission, whereas N2O emission from the FWS unit was nearly zero. On the other hand, the CH4 emission was not so high as N2O in the combined CW system, which mainly emitted from the FWS and SF units.

  18. Greenhouse gases generated from the anaerobic biodegradation of natural offshore asphalt seepages in southern California

    USGS Publications Warehouse

    Lorenson, T.D.; Wong, Florence L.; Dartnell, Peter; Sliter, Ray W.

    2014-01-01

    Significant offshore asphaltic deposits with active seepage occur in the Santa Barbara Channel offshore southern California. The composition and isotopic signatures of gases sampled from the oil and gas seeps reveal that the coexisting oil in the shallow subsurface is anaerobically biodegraded, generating CO2 with secondary CH4 production. Biomineralization can result in the consumption of as much as 60% by weight of the original oil, with 13C enrichment of CO2. Analyses of gas emitted from asphaltic accumulations or seeps on the seafloor indicate up to 11% CO2 with 13C enrichment reaching +24.8‰. Methane concentrations range from less than 30% up to 98% with isotopic compositions of –34.9 to –66.1‰. Higher molecular weight hydrocarbon gases are present in strongly varying concentrations reflecting both oil-associated gas and biodegradation; propane is preferentially biodegraded, resulting in an enriched 13C isotopic composition as enriched as –19.5‰. Assuming the 132 million barrels of asphaltic residues on the seafloor represent ~40% of the original oil volume and mass, the estimated gas generated is 5.0×1010 kg (~76×109 m3) CH4 and/or 1.4×1011 kg CO2 over the lifetime of seepage needed to produce the volume of these deposits. Geologic relationships and oil weathering inferences suggest the deposits are of early Holocene age or even younger. Assuming an age of ~1,000 years, annual fluxes are on the order of 5.0×107 kg (~76×106 m3) and/or 1.4×108 kg for CH4 and CO2, respectively. The daily volumetric emission rate (2.1×105 m3) is comparable to current CH4 emission from Coal Oil Point seeps (1.5×105 m3/day), and may be a significant source of both CH4 and CO2 to the atmosphere provided that the gas can be transported through the water column.

  19. Modelling absorption and dilution of unconfined releases of hazardous gases by water curtains or monitors

    SciTech Connect

    Fthenakis, V.M.; Blewitt, D.N.; Hague, W.J.

    1995-05-01

    OSHA Process Safety Management guidelines suggest that a facility operator investigate and document a plan for installing systems to detect, contain, or mitigate accidental releases if such systems are not already in place. In addition, proposed EPA 112(r) regulations would require such analysis. This paper illustrates how mathematical modelling can aid such an evaluation and describes some recent enhancements of the HGSPRAY model: (1) Adding algorithms for modeling NH{sub 3} and LNG mitigation; (2) Modeling spraying of releases with fire water monitors encircling the point of release; (3) Combining wind tunnel modeling with mathematical modeling; and (4) Linking HGSPRAY and BEGADAS. Case cases are presented as examples of how HGSPRAY can aid the design of water spray systems for initiation of toxic gases (e.g., BF, NH,) or dilution/dispersion of flammable vapors (e.g., LNG).

  20. Greenhouse gases, Regulated Emissions, and Energy use in Transportation fuel-cyl

    Energy Science and Technology Software Center (ESTSC)

    2000-06-20

    The GREET model estimates the full fuel-cycle energy use and emissions associated with various transportation fuels and advanced vehile technologies applied to motor vehicles. GREET 1.5 includes the following cycles: petroleum to conventional gasoline, reformulated gasoline, conventional diesel, reformulated diesel, liquefied petroleum gas, and electricity via residual oil; natural gas to compressed natural gas, liquefied natural gas, liquefied petroleum gas, methanol, Fischer-Tropsch diesel, dimethyl ether, hydrogen, and electricity; coal to electricity; corn, woody biomass, andmore » herbaceous biomass to ethanol; soybeans to biodiesel; flared gas to methanol, Fischer-Tropsch diesel, and dimethyl ether; and landfill gases to methanol. For a given fuel/transportation technology combination, GREET 1.5 calculates (1) the fuel-cycle consumption of total energy (all energy sources), fossil fuels (petroleum, natural gas, and coal), and petroleum; (2) the fuel-cycle emissions of GHGs -- primarily carbon dioxide (CO2), methane (CH4), and nitrous oxide (N20); and (3) the fuel-cycle emissions of five criteria pollutants: volatile organic compounds (VOCs), carbon monoxide (C0), nitrogen oxides (N0x), sulfur oxides (S0x), and particulate matter with a diameter measuring 10 micrometers or less (PM10). The model is designed to readily allow researchers to input their own assumptions and generate fuel-cycle energy and emission results for specified fuel/technology combinations.« less

  1. Emission Factors of Greenhouse Gases and Particulates from Australian Savanna Fires

    NASA Astrophysics Data System (ADS)

    Desservettaz, M.; Paton-Walsh, C.; Griffith, D. W. T.; Kettlewell, G.; Wilson, S. R.; Keywood, M. D.; van der Schoot, M. V.; Selleck, P. W.; Ward, J.; Harnwell, J.; Reisen, F.; Lawson, S. J.; Ristovski, Z.; Mallet, M.; Miljevic, B.; Atkinson, B.; Milic, A.

    2015-12-01

    In June 2014 a measurement campaign took place at Gunn Point in the Northern Territory, Australia, aimed at characterising the emissions from early dry season savanna fires. The campaign was especially focused on understanding aerosol composition and size distribution. Equipment deployed to measure aerosol properties included a multi-angle absorption photometer, a nephelometer, a cloud condensation nuclei counter, a condensation particle counter, two scanning mobility particle sizer, two aerosol mass spectrometers (one a time of flight instrument) , a multi-axis differential optical absorption spectrometer, a volatility-humidity tandem differential mobility analyser and two high volume aerosol samplers (one PM10 and one MOUDI). In addition there were measurements of mercury in both gas and aerosol phase. Complementary measurements of trace gases were provided by a proton transfer reaction mass spectrometer, a volatile organic compounds sequencer, a Fourier transform spectrometer, an ozone analyser and a nitrogen oxides monitor. This presentation will present results from the Fourier transform spectrometer, the scanning mobility particulate sizer, the beta attenuation monitor and the aerosol mass spectrometer. In particular individual fire events have been identified and emission factors calculated for CO2, CO, CH4 N2O and aerosols (PM1, PM10, Aitken and Accumulation mode).

  2. Quantified estimates of total GWPs for greenhouse gases taking into account tropospheric chemistry

    SciTech Connect

    Wuebbles, D.J.; Tamaresis, J.S.; Patten, K.O.

    1993-11-01

    The purpose of this report is to give interim account of the progress being made at Lawrence Livermore National Laboratory (LLNL) in developing an improved capability for assessing the direct and indirect effects on Global Warming Potentials. Much of our current efforts are being devoted to improving the capability for modeling of global tropospheric processes in our state-of-the-art zonally-averaged chemical-radiative-transport model of the troposphere and stratosphere. These efforts are in preparation for an improved evaluation and better quantification of the indirect GWPs resulting from effects on tropospheric ozone from ethane and other gases with significant human-related emissions. There are three major findings that should result from this project that should have significant impacts on EPA and its programs. First, the current and ongoing studies of the direct and indirect GWPs should have a significant influence on the continuing national and international assessments of climate change. Second, the improved capability for modeling of chemical and physical processes should lead to enhanced understanding of the controlling factors influencing ozone, hydroxyl and other key tropospheric constituents. Third, the enhanced modeling capability should be important to future studies of human-related influences on tropospheric and stratospheric chemical processes.

  3. Emissions of greenhouse gases from the tropical hydroelectric reservoir of Petit Saut (French Guiana) compared with emissions from thermal alternatives

    NASA Astrophysics Data System (ADS)

    Delmas, Robert; Galy-Lacaux, Corinne; Richard, Sandrine

    2001-12-01

    Greenhouse gas (GHG) emissions of CH4 and CO2, resulting from decomposition of flooded organic matter from the hydroelectric reservoir of Petit Saut in the tropical rain forest of French Guiana have been monitored since reservoir impoundment in January 1994. This data set along with complementary data taken from older reservoirs in forested regions of the southern Ivory Coast provides an estimate of long-term GHG emission trends from a tropical reservoir. The trends are used to calculate the contribution of this reservoir to global warming on a 100 year timescale, assumed to be consistent with the life cycle of the reservoir. Calculations are based on the concept of global warming potential (GWP). Natural emission of greenhouse gases (CH4 and N2O) from soils of the reservoir before impoundment is estimated through field measurements and literature data. Then net GHG emissions from the reservoir on a 100 hundred year timescale (30 million tons of equivalent CO2, with an uncertainty range of 7-54 Mt CO2eq) are compared with predicted emissions from thermal power plants of equivalent power (115 MW). The final comparison takes into account the actual energy production of the dam power station at only 50% of the installed capacity. Emission from this reservoir, whose power density is low (0.315 MW km-2 flooded), would be similar to emissions from a gas power plant (33 Mt CO2eq) producing the same energy amount and less than emissions from other thermal alternatives, among which the most polluting are coal plants. Such a result, however, strongly depends on the choice of the integration time.

  4. ACCURATE: Influence of Cloud Layers and Aerosol on Infrared Laser Occultation Signals for Sensing of Greenhouse Gases

    NASA Astrophysics Data System (ADS)

    Proschek, V.; Schweitzer, S.; Emde, C.; Ladstädter, F.; Fritzer, J.; Kirchengast, G.

    2009-04-01

    ACCURATE (Atmospheric Climate and Chemistry in the UTLS Region And climate Trends Explorer), a new climate satellite concept, enables simultaneous measurement of profiles of greenhouse gases, isotopes, wind and thermodynamic variables from Low Earth Orbit (LEO) satellites. The measurement principle applied is a combination of the novel LEO-LEO infrared laser occultation (LIO) technique and the well-studied but not yet flown LEO-LEO microwave occultation (LMO) technique. As intrinsic to the space-borne occultation technique, the measurements are evenly distributed around the world, have high vertical resolution and high accuracy and are stable over long time periods. The LIO uses near-monochromatic signals in the short-wave infrared range (~2-2.5 m in the case of ACCURATE) which are absorbed by various trace species in the Earth's atmosphere. From signal transmission measurements, profiles of the concentration of the absorbing species can be derived given that temperature and pressure are accurately known from LMO. The current ACCURATE mission design is arranged for the measurement of six greenhouse gases (H2O, CO2, CH4, N2O, O3, CO) and four isotopes (13CO2, C18OO, HDO, H218O) with focus on the upper troposphere/lower stratosphere region (UTLS, 5-35 km). Wind speed in line-of-sight can be derived from a line-symmetric transmission difference which is caused by wind-induced Doppler shift. By-products are information on cloud layering, aerosol extinction and scintillation strength. This contribution presents an overview on the ACCURATE mission design and the expected accuracy of retrieved atmospheric variables and further focuses on the influence of clouds and aerosols on propagating LIO signals. Special emphasis will be given to sub-visible cirrus clouds which are semi-transparent to infrared signals. A simple frequency dependent cloud extinction parametrization was included into the occultation propagation software EGOPS and evaluated against results of the

  5. Interaction of biochar and organic residues from sugarcane industry in soil chemical attributes and greenhouse gases emissions.

    NASA Astrophysics Data System (ADS)

    Fernanda Abbruzzini, Thalita; Feola Conz, Rafaela; Pellegrino Cerri, Carlos Eduardo

    2014-05-01

    Researchers have highlighted the importance of providing soil quality in agricultural systems, besides mitigating greenhouse gases (GHG) emissions to the atmosphere and increasing soil carbon sequestration. Therefore, several studies have demonstrated the effectiveness of biochar as a soil conditioner, both in relation to increased C sequestration and improvements in soil chemical, physical and biological attributes, resulting in better conditions for plant growth. The aim of this study was to assess the impact of applying biochar produced from sugarcane straw to soils in relation to changes in soil chemical attributes and mitigation of greenhouse gases emissions into the atmosphere. To do so, we conducted a laboratory incubation under controlled environmental conditions (ie temperature and humidity) with and without the application of filter cake and vinasse (ie organic residues from sugarcane industry) and rates of biochar application (0, 10, 20 and 50 Mg ha-1). The fluxes of CO2, N2O and CH4 of each incubation unity were measured periodically (in days 1, 2, 5, 9, 13, 16, 20, 24, 28, 30, 47, 60, 91, 105, 123, 130, 138 and 150). Each treatment consisted of eight replicates with destructive samples evaluated at 30, 60, 90 and 150 days after incubation to characterize the chemical attributes of the incubated soil, besides GHG (CO2, N2O and CH4) emissions. In general, there was an increase in carbon dioxide (CO2) fluxes over time due to the application of filter cake and vinasse and increasing dose of biochar. Regarding nitrous oxide (N2O) emissions, there was an increase of 82.35% with the application of vinasse and filter cake compared to the control treatment. However, different doses of biochar (10, 20 and 50 Mg ha-1) reduced N2O emissions by 29, 38.7 and 70.9%, respectively. The methane (CH4) flux was negligible in all treatments. We observed improvements in soil chemical attributes, such as higher pH, a substantial increase in the soil CEC, reduced exchangeable

  6. Recycling of plastic: accounting of greenhouse gases and global warming contributions.

    PubMed

    Astrup, Thomas; Fruergaard, Thilde; Christensen, Thomas H

    2009-11-01

    Major greenhouse gas (GHG) emissions related to plastic waste recycling were evaluated with respect to three management alternatives: recycling of clean, single-type plastic, recycling of mixed/contaminated plastic, and use of plastic waste as fuel in industrial processes. Source-separated plastic waste was received at a material recovery facility (MRF) and processed for granulation and subsequent downstream use. In the three alternatives, plastic was assumed to be substituting virgin plastic in new products, wood in low-strength products (outdoor furniture, fences, etc.), and coal or fuel oil in the case of energy utilization. GHG accounting was organized in terms of indirect upstream emissions (e.g. provision of energy, fuels, and materials), direct emissions at the MRF (e.g. fuel combustion), and indirect downstream emissions (e.g. avoided emissions from production of virgin plastic, wood, or coal/oil). Combined, upstream and direct emissions were estimated to be roughly between 5 and 600 kg CO(2)-eq. tonne( -1) of plastic waste depending on treatment at the MRF and CO(2) emissions from electricity production. Potential downstream savings arising from substitution of virgin plastic, wood, and energy fuels were estimated to be around 60- 1600 kg CO(2)-eq. tonne( -1) of plastic waste depending on substitution ratios and CO(2) emissions from electricity production. Based on the reviewed data, it was concluded that substitution of virgin plastic should be preferred. If this is not viable due to a mixture of different plastic types and/or contamination, the plastic should be used for energy utilization. Recycling of plastic waste for substitution of other materials such as wood provided no savings with respect to global warming. PMID:19748943

  7. Fluxes of Greenhouse Gases from the Baltimore-Washington Area: Results from WINTER 2015 Aircraft Observations

    NASA Astrophysics Data System (ADS)

    Dickerson, R. R.; Ren, X.; Shepson, P. B.; Salmon, O. E.; Brown, S. S.; Thornton, J. A.; Whetstone, J. R.; Salawitch, R. J.; Sahu, S.; Hall, D.; Grimes, C.; Wong, T. M.

    2015-12-01

    Urban areas are responsible for a major component of the anthropogenic greenhouse gas (GHG) emissions. Quantification of urban GHG fluxes is important for establishing scientifically sound and cost-effective policies for mitigating GHGs. Discrepancies between observations and model simulations of GHGs suggest uncharacterized sources in urban environments. In this work, we analyze and quantify fluxes of CO2, CH4, CO (and other trace species) from the Baltimore-Washington area based on the mass balance approach using the two-aircraft observations conducted in February-March 2015. Estimated fluxes from this area were 110,000±20,000 moles s-1 for CO2, 700±330 moles s-1 for CH4, and 535±188 moles s-1 for CO. This implies that methane is responsible for ~20% of the climate forcing from these cities. Point sources of CO2 from four regional power plants and one point source of CH4 from a landfill were identified and the emissions from these point sources were quantified based on the aircraft observation and compared to the emission inventory data. Methane fluxes from the Washington area were larger than from the Baltimore area, indicating a larger leakage rate in the Washington area. The ethane-to-methane ratios, with a mean of 3.3%, in the limited canister samples collected during the flights indicate that natural gas leaks and the upwind oil and natural gas operations are responsible for a substantial fraction of the CH4 flux. These observations will be compared to models using Ensemble Kalman Filter Assimilation techniques.

  8. Carbon and nitrogen dynamics and greenhouse gases emissions in constructed wetlands: a review

    NASA Astrophysics Data System (ADS)

    Jahangir, M. M. R.; Fenton, O.; Gill, L.; Müller, C.; Johnston, P.; Richards, K. G.

    2014-07-01

    The nitrogen (N) removal efficiency of constructed wetlands (CWs) is very inconsistent and does not alone explain if the removed species are reduced by physical attenuation or if they are transformed to other reactive forms (pollution swapping). There are many pathways for the removed N to remain in the system: accumulation in the sediments, leaching to groundwater (nitrate-NO3- and ammonium-NH4+), emission to atmosphere via nitrous oxide- N2O and ammonia and/or conversion to N2 gas and adsorption to sediments. The kinetics of these pathways/processes varies with CWs management and therefore needs to be studied quantitatively for the sustainable use of CWs. For example, the quality of groundwater underlying CWs with regards to the reactive N (Nr) species is largely unknown. Equally, there is a dearth of information on the extent of Nr accumulation in soils and discharge to surface waters and air. Moreover, CWs are rich in dissolved organic carbon (DOC) and produce substantial amounts of CO2 and CH4. These dissolved carbon (C) species drain out to ground and surface waters and emit to the atmosphere. The dynamics of dissolved N2O, CO2 and CH4 in CWs is a key "missing piece" in our understanding of global greenhouse gas budgets. In this review we provide an overview of the current knowledge and discussion about the dynamics of C and N in CWs and their likely impacts on aquatic and atmospheric environments. We suggest that the fate of various N species in CWs and their surface emissions and subsurface drainage fluxes need to be evaluated in a holistic way to better understand their potential for pollution swapping. Research on the process based N removal and balancing the end products into reactive and benign forms are critical to assess environmental impacts of CWs. Thus we strongly suggest that in situ N transformation and fate of the transformation products with regards to pollution swapping requires further detailed examination.

  9. Potential effects of clean coal technologies on acid precipitation, greenhouse gases, and solid waste disposal

    SciTech Connect

    Blasing, T.J.; Miller, R.L.; McCold, L.N.

    1993-11-01

    The US Department of Energy`s (DOE`s) Clean Coal Technology Demonstration Program (CCTDP) was initially funded by Congress to demonstrate more efficient, economically feasible, and environmentally acceptable coal technologies. Although the environmental focus at first was on sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) because their relationship to acid precipitation, the CCTDP may also lead to reductions in carbon dioxide (CO{sub 2}) emissions and in the volume of solid waste produced, compared with conventional technologies. The environmental effects of clean coal technologies (CCTs) depend upon which (if any) specific technologies eventually achieve high acceptance in the marketplace. In general, the repowering technologies and a small group of retrofit technologies show the most promise for reducing C0{sub 2} emissions and solid waste. These technologies also compare favorably with other CCTs in terms of SO{sub 2} and NO{sub x} reductions. The upper bound for CO{sup 2} reductions in the year 2010 is only enough to reduce global ``greenhouse`` warming potential by about 1%. However, CO{sub 2} emissions come from such variety of sources around the globe that no single technological innovation or national policy change could realistically be expected to reduce these emissions by more than a few percent. Particular CCTs can lead to either increases or decreases in the amount of solid waste produced. However, even if decreases are not achieved, much of the solid waste from clean coal technologies would be dry and therefore easier to dispose of than scrubber sludge.

  10. Anaerobic digestion and digestate use: accounting of greenhouse gases and global warming contribution.

    PubMed

    Møller, Jacob; Boldrin, Alessio; Christensen, Thomas H

    2009-11-01

    Anaerobic digestion (AD) of source-separated municipal solid waste (MSW) and use of the digestate is presented from a global warming (GW) point of view by providing ranges of greenhouse gas (GHG) emissions that are useful for calculation of global warming factors (GWFs), i.e. the contribution to GW measured in CO(2)-equivalents per tonne of wet waste. The GHG accounting was done by distinguishing between direct contributions at the AD facility and indirect upstream or downstream contributions. GHG accounting for a generic AD facility with either biogas utilization at the facility or upgrading of the gas for vehicle fuel resulted in a GWF from -375 (a saving) to 111 (a load) kg CO(2)-eq. tonne(-1) wet waste. In both cases the digestate was used for fertilizer substitution. This large range was a result of the variation found for a number of key parameters: energy substitution by biogas, N(2)O-emission from digestate in soil, fugitive emission of CH( 4), unburned CH(4), carbon bound in soil and fertilizer substitution. GWF for a specific type of AD facility was in the range -95 to -4 kg CO(2)-eq. tonne(-1) wet waste. The ranges of uncertainty, especially of fugitive losses of CH(4) and carbon sequestration highly influenced the result. In comparison with the few published GWFs for AD, the range of our data was much larger demonstrating the need to use a consistent and robust approach to GHG accounting and simultaneously accept that some key parameters are highly uncertain. PMID:19748957

  11. Hydrologic Profiling for Greenhouse Gases from Prairie Potholes in Western Canada

    NASA Astrophysics Data System (ADS)

    Creed, I. F.; Aldred, D. A.; Bourbonniere, R. A.

    2010-12-01

    The Prairie Pothole Region is a unique physiographic region covering a large portion of the central Great Plains of North America that is populated by shallow depressions or “potholes” of varying size. Potholes typically fill with water after snowmelt, forming ephemeral or permanent ponds surrounded by concentric bands of soils with water contents. These ponds vary both in space and time, defining the “hydrologic profile” of the pothole. We tested the hypothesis that hydrologic profiles are important drivers of biogeochemical activity, including the transport of the greenhouse gas (GHG) precursors, which influence GHG exchanges from contributing source areas towards the ponds. Potholes at five study nodes along a N-S climatic gradient in south central Saskatchewan (with precipitation-potential evapotranspiration ranging from -520 mm/yr to -270 mm/yr) were selected for study. Topographic features representing positions along the hydrologic profile from dry to wet (crest, shoulder, backslope, footslope and toeslope) were derived through digital terrain analysis of LiDAR digital elevation models (DEMs) and were used as the basis for satellite (Radarsat-1) estimates of soil water content. The satellite derived soil water contents were then related to CO2, CH4 and N2O GHG effluxes during the growing season (May to September). Within potholes, nonlinear relationships between hydrological profiles and soil GHG effluxes were observed. In general, backslopes yielded the highest N2O fluxes, footslopes and toeslopes yielded the highest CO2, and inundated portions of the pothole yielded the highest CH4. However, the magnitude of GHG effluxes varied over the growing season, with peak magnitudes typically occurring in late summer. Among the study nodes, GHG global warming potential decreased from south (dry) to north (wet). These findings illustrate that static topographic features derived from LiDAR DEMs can be fused with dynamic soil water contents derived from radar

  12. Quantifying the Sources and Sinks of Greenhouse Gases: What Does It Take to Satisfy Scientific and Decision-Making Needs?

    NASA Astrophysics Data System (ADS)

    Davis, K. J.; Keller, K.; Ogle, S. M.; Smith, S.

    2014-12-01

    Changes in the sources and sinks of greenhouse gases (GHGs) are key drivers of anthropogenic climate change. It is hence not surprising that current and emerging U.S. governmental science priorities and programs focused on climate change (e.g. a U.S. Carbon Cycle Science Plan; the U.S. Carbon Cycle Science Program, the U.S. Global Change Research Program, Executive Order 13653 'Preparing the U.S. for the Impacts of Climate Change') all call for an improved understanding of these sources and sinks.. Measurements of the total atmospheric burden of these gases are well established, but measurements of their sources and sinks are difficult to make over spatial and temporal scales that are relevant for scientific and decisionmaking needs. Quantifying the uncertainty in these measurements is particularly challenging. This talk reviews the intersection of the state of knowledge of GHG sources and sinks, focusing in particular on CO2 and CH4, and science and decision-making needs for this information. Different science and decision-making needs require differing levels of uncertainty. A number of high-priority needs (early detection of changes in the Earth system, projections of future climate, support of markets or regulations) often require a high degree of accuracy and/or precision. We will critically evaluate current U.S. planning to documents to infer current perceived needs for GHG source/sink quantification, attempting to translate these needs into quantitative uncertainty metrics. We will compare these perceived needs with the current state of the art of GHG source/sink quantification, including the apparent pattern of systematic differences between so-called "top down" and "bottom-up" flux estimates. This comparison will enable us to identify where needs can be readily satisfied, and where gaps in technology exist. Finally, we will examine what steps could be taken to close existing gaps.

  13. Sources of greenhouse gases and carbon monoxide in central London (UK)

    NASA Astrophysics Data System (ADS)

    Helfter, Carole; Tremper, Anja; Zazzeri, Giulia; Barlow, Janet F.; Nemitz, Eiko

    2015-04-01

    Biosphere-atmosphere exchange of carbon dioxide (CO2) has been on the scientific agenda for several decades and new technology now also allows for high-precision, continuous monitoring of fluxes of methane (CH4) and nitrous oxide (N2O). Compared to the natural environment, flux measurements in the urban environment, which is home to over 50% of the population globally, are still rare despite high densities of anthropogenic sources of pollutants. We report on over three years of measurements atop a 192 m tower in central London (UK), Europe's largest city, which started in October 2011. Fluxes of methane, carbon monoxide (CO) and carbon dioxide are measured by eddy-covariance (EC) at the British Telecom tower (51° 31' 17.4' N 0° 8' 20.04' W). In addition to the long-term measurements, EC fluxes of nitrous oxide (N2O) were measured in February 2014. All four trace gases exhibit diurnal trends consistent with anthropogenic activities with minimum emissions at night and early afternoon maxima. Segregating emissions by wind direction reveals heterogeneous source distributions with temporal patterns and source strengths that differ between compounds. The lowest emissions for CO, CO2 and CH4 were recorded for NW winds. The highest emissions of methane were in the SE sector, in the NE for CO2 and in the W for CO. Fluxes of all 3 gases exhibited marked seasonal trends characterised by a decrease in emissions in summer (63% reduction for CO, 36% for CO2 and 22% for CH4). Monthly fluxes of CO and CO2 were linearly correlated to air temperature (R2 = 0.7 and 0.59 respectively); a weaker dependence upon temperature was also observed for CH4 (R2 = 0.31). Diurnal and seasonal emissions of CO and CO2 are mainly controlled by local fossil fuel combustion and vehicle cold starts are thought to account for 20-30% of additional emissions of CO during the winter. Fugitive emissions of CH4 from the natural gas distribution network are thought to be substantial, which is consistent

  14. Oral drug delivery of therapeutic gases - carbon monoxide release for gastrointestinal diseases.

    PubMed

    Steiger, Christoph; Lühmann, Tessa; Meinel, Lorenz

    2014-09-10

    Deploying the therapeutic potential of carbon monoxide (CO) in various gastrointestinal diseases is challenged by inappropriate oral delivery modes. It is for this challenge, that we developed an easy to use tablet referred to as oral carbon monoxide release system (OCORS) providing precise, controlled, tunable and targeted CO delivery for the treatment of sequelae of gastrointestinal diseases. OCORS is an oral tablet based on sulfite induced CO release from the CO releasing molecule 2 (CORM-2). OCORS performance was detailed as a function of the presence of buffer within the tablet core and the composition of a semipermeable cellulose acetate coating, shielding the tablet core. OCORS delivered CO for up to 10h with a nearly linear release profile between approximately 30 to 240min. This controlled release system delivered the therapeutic gas independent of environmental pH for reliable CO generation at gastric, intestinal or colonic sites. In vivo experiments and toxicological assessments particularly with respect to observed ruthenium release of OCORS are required to demonstrate the pharmacokinetics and clinical potential of this oral delivery platform for therapeutic gases. PMID:24969354

  15. A new UK Greenhouse Gas measurement network providing ultra high-frequency measurements of key radiatively active trace gases taken from a network of tall towers

    NASA Astrophysics Data System (ADS)

    Grant, A.; O'Doherty, S.; Manning, A. J.; Simmonds, P. G.; Derwent, R. G.; Moncrieff, J. B.; Sturges, W. T.

    2012-04-01

    Monitoring of atmospheric concentrations of gases is important in assessing the impact of international policies related to the atmospheric environment. The effects of control measures on greenhouse gases introduced under the Montreal and Kyoto Protocols are now being observed. Continued monitoring is required to assess the overall success of the Protocols. For over 15 years the UK Government have funded high-frequency measurements of greenhouse gases and ozone depleting gases at Mace Head, a global background measurement station on the west coast of Ireland. These continuous, high-frequency, high-precision measurements are used to estimate regional (country-scale) emissions of greenhouse gases across the UK using an inversion methodology (NAME-Inversion) that links the Met Office atmospheric dispersion model (Numerical Atmospheric dispersion Modelling Environment - NAME) with the Mace Head observations. This unique inversion method acts to independently verify bottom up emission estimates of radiatively active and ozone-depleting trace gases. In 2011 the UK government (DECC) funded the establishment and integration of three new tall tower measurements stations in the UK, to provide enhanced resolution emission maps and decrease uncertainty of regional emission estimates produced using the NAME-Inversion. One station included in this new UK network was already established in Scotland and was used in collaboration with Edinburgh University. The two other new stations are in England and were set-up early in 2012, they contain brand new instrumentation for measurements of greenhouse gases. All three additional stations provide ultra high-frequency (1 sec) data of CO2 and CH4 using the Picarro© Cavity Ring Down Spectrometer and high frequency (20 min) measurements of N2O and SF6 from custom built sample modules with GC-ECD. We will present the new tall tower UK measurement network in detail. Using high-frequency measurements at new operational sites, including Mace

  16. Eddy covariance measurements of greenhouse gases from a restored and rewetted raised bog ecosystem.

    NASA Astrophysics Data System (ADS)

    Lee, S. C.; Christen, A.; Black, T. A.; Johnson, M. S.; Ketler, R.; Nesic, Z.; Merkens, M.

    2015-12-01

    Wetland ecosystems play a significant role in the global carbon (C) cycle. Wetlands act as a major long-term storage of carbon by sequestrating carbon-dioxide (CO2) from the atmosphere. Meanwhile, they can emit significant amounts of methane (CH4) due to anaerobic microbial decomposition. The Burns Bog Ecological Conservancy Area (BBECA) is recognized as one of Canada's largest undeveloped natural areas retained within an urban area. Historically, it has been substantially reduced in size and degraded by peat mining and agriculture. Since 2005, the bog has been declared a conservancy area, and the restoration efforts in BBECA focus on rewetting the disturbed ecosystems to promote a transition back to a raised bog. A pilot study measured CH4, CO2 and N2O exchanges in 2014 and concluded to monitor CO2, CH4 fluxes continuously. From the perspective of greenhouse gas (GHG) emissions, CO2 sequestered in bog needs to be protected and additional CO2 and CH4 emissions due to land-cover change need to be reduced by wise management. In this study, we measured the growing-season (June-September) fluxes of CO2 and CH4 exchange using eddy covariance (EC). A floating platform with an EC system for both CO2 (closed-path) and CH4 (open-path) began operation in June 2015. During the growing-season, gross ecosystem photosynthesis (GEP) and ecosystem respiration (Re) averaged 5.87 g C m-2 day-1 and 2.02 g C m-2 day-1, respectively. The magnitude of GEP and Re were lower than in previous studies of pristine northern peatlands. The daily average CH4 emission was 0.99 (±1.14) g C m-2 day-1 and it was higher than in most previous studies. We also characterized how environmental factors affected the seasonal dynamics of these exchanges in this disturbed peatland. Our measurements showed that soil temperature and soil water content were major drivers of seasonal changes of GHG fluxes. The daily average GHG warming potential (GWP) of the emissions in the growing seasons (from CO2 and CH4

  17. Why the developing nations like India need strong capacity building efforts in greenhouse gases mitigation?

    NASA Astrophysics Data System (ADS)

    Vishal, V.; Sudhakaran, A.; Singh, T. N.

    2014-12-01

    Today, India rubs shoulders with nations like USA and China for being the major shareholders in global greenhouse emissions and has more emissions than Russia! Carbon Capture, Utilization and Storage (CCUS) has been proven as a reliable method to counter global warming and keep the 2ºC per year policy in check and is currently in the pilot stage in many developed nations. The three major requirements for CCUS are: manpower in diverse fields, implementation potential and capital. Keeping other social problems aside, India still has sufficient mankind in all spheres of research ranging from earth science, engineering, basic sciences, economy, policy making, regulation, public outreach etc. to successfully work on such challenges. India has leading academic institutions, research labs and universities in science and engineering. They also have a working power force in aspects like economy, policy making, regulation, public outreach etc. in various management institutes of repute. India, however, lacks in sufficient funding for advanced research and capacity building schemes to support projects of such scale. Deployment of facts and concepts on climate change need an approach of much greater scope than what is anticipated. The above workforces can put forth a clear picture about the various entities surrounding CCUS and provide sensible planning and implementation information through scientific research. CCUS is only possible when the direct anthropogenic emitters like fossil fuel plants modify their features to incorporate the methods associated with it. The rural population has to be educated in context to the safety of the storage sites. Above all, the Indian government must holistically divert funds for such programs and provide economic incentives to the industries for the industries. The bottom line is that India has been working in lots of aspects with not very clear cuts objectives. There are CO2 capture technologies like amine scrubbing and membrane

  18. An environmental and economic evaluation of pyrolysis for energy generation in Taiwan with endogenous land greenhouse gases emissions.

    PubMed

    Kung, Chih-Chun; McCarl, Bruce A; Chen, Chi-Chung

    2014-03-01

    Taiwan suffers from energy insecurity and the threat of potential damage from global climate changes. Finding ways to alleviate these forces is the key to Taiwan's future social and economic development. This study examines the economic and environmental impacts when ethanol, conventional electricity and pyrolysis-based electricity are available alternatives. Biochar, as one of the most important by-product from pyrolysis, has the potential to provide significant environmental benefits. Therefore, alternative uses of biochar are also examined in this study. In addition, because planting energy crops would change the current land use pattern, resulting in significant land greenhouse gases (GHG) emissions, this important factor is also incorporated. Results show that bioenergy production can satisfy part of Taiwan's energy demand, but net GHG emissions offset declines if ethanol is chosen. Moreover, at high GHG price conventional electricity and ethanol will be driven out and pyrolysis will be a dominant technology. Fast pyrolysis dominates when ethanol and GHG prices are low, but slow pyrolysis is dominant at high GHG price, especially when land GHG emissions are endogenously incorporated. The results indicate that when land GHG emission is incorporated, up to 3.8 billion kWh electricity can be produced from fast pyrolysis, while up to 2.2 million tons of CO2 equivalent can be offset if slow pyrolysis is applied. PMID:24619159

  19. Evaluation of process conditions triggering emissions of green-house gases from a biological wastewater treatment system.

    PubMed

    Rodriguez-Caballero, A; Aymerich, I; Poch, M; Pijuan, M

    2014-09-15

    In this study, methane (CH4) and nitrous oxide (N2O) emission dynamics of a plug-flow bioreactor located in a municipal full-scale wastewater treatment plant were monitored during a period of 10 weeks. In general, CH4 and N2O gas emissions from the bioreactor accounted for 0.016% of the influent chemical oxygen demand (COD) and 0.116% of the influent total Kjeldahl nitrogen (TKN) respectively. In order to identify the emission patterns in the different zones, the bioreactor was divided in six different sampling sites and the gas collection hood was placed for a period of 2-3 days in each of these sites. This sampling strategy also allowed the identification of different process perturbations leading to CH4 or N2O peak emissions. CH4 emissions mainly occurred in the first aerated site, and were mostly related with the influent and reject wastewater flows entering the bioreactor. On the other hand, N2O emissions were given along all the aerated parts of the bioreactor and were strongly dependant on the occurrence of process disturbances such as periods of no aeration or nitrification instability. Dissolved CH4 and N2O concentrations were monitored in the bioreactor and in other parts of the plant, as a contribution for the better understanding of the transport of these greenhouse gases across the different stages of the treatment system. PMID:24954560

  20. Attribution of Ozone Changes in the Near Future: Nonlinear Feedbacks between Ozone Depleting Substances and Greenhouse Gases

    NASA Astrophysics Data System (ADS)

    Meul, Stefanie; Oberländer, Sophie; Langematz, Ulrike

    2014-05-01

    In the first half of the 21st century the stratospheric burden of ozone depleting substances (ODSs) is predicted to decrease due to the regulations in the Montreal Protocol and its amendments. Concomitantly, the concentrations of well-mixed greenhouse gases (GHGs) will continue to rise. As the removal of the ODSs from the stratosphere is also affected by changes in the Brewer-Dobson Circulation, the decrease of halogens will also depend on the rate of the GHG increase. Furthermore, the increasing concentrations of the GHGs methane (CH4) and nitrous oxide (N2O) can modify the halogen-ozone chemistry. Therefore, a non-linear contribution has to be included in the attribution analysis of the ozone changes to ODS and GHG changes. In this study we detect and analyze this non-linear term in a set of appropriately defined timeslice simulations for the year 2045 with the Chemistry-Climate-Model EMAC. The causal processes of the non-linear interactions are studied in more detail by separating the relative ozone changes in the contribution from chemistry (production and loss) and transport. This allows us to identify not only feedbacks between chemistry and temperature but also between chemistry and dynamics, i.e. ozone transport.

  1. An Environmental and Economic Evaluation of Pyrolysis for Energy Generation in Taiwan with Endogenous Land Greenhouse Gases Emissions

    PubMed Central

    Kung, Chih-Chun; McCarl, Bruce A.; Chen, Chi-Chung

    2014-01-01

    Taiwan suffers from energy insecurity and the threat of potential damage from global climate changes. Finding ways to alleviate these forces is the key to Taiwan’s future social and economic development. This study examines the economic and environmental impacts when ethanol, conventional electricity and pyrolysis-based electricity are available alternatives. Biochar, as one of the most important by-product from pyrolysis, has the potential to provide significant environmental benefits. Therefore, alternative uses of biochar are also examined in this study. In addition, because planting energy crops would change the current land use pattern, resulting in significant land greenhouse gases (GHG) emissions, this important factor is also incorporated. Results show that bioenergy production can satisfy part of Taiwan’s energy demand, but net GHG emissions offset declines if ethanol is chosen. Moreover, at high GHG price conventional electricity and ethanol will be driven out and pyrolysis will be a dominant technology. Fast pyrolysis dominates when ethanol and GHG prices are low, but slow pyrolysis is dominant at high GHG price, especially when land GHG emissions are endogenously incorporated. The results indicate that when land GHG emission is incorporated, up to 3.8 billion kWh electricity can be produced from fast pyrolysis, while up to 2.2 million tons of CO2 equivalent can be offset if slow pyrolysis is applied. PMID:24619159

  2. Low-power, open-path mobile sensing platform for high-resolution measurements of greenhouse gases and air pollutants

    NASA Astrophysics Data System (ADS)

    Tao, Lei; Sun, Kang; Miller, David J.; Pan, Dan; Golston, Levi M.; Zondlo, Mark A.

    2015-04-01

    A low-power mobile sensing platform has been developed with multiple open-path gas sensors to measure the ambient concentrations of greenhouse gases and air pollutants with high temporal and spatial resolutions over extensive spatial domains. The sensing system consists of four trace gas sensors including two custom quantum cascade laser-based open-path sensors and two LICOR open-path sensors to measure CO2, CO, CH4, N2O, NH3, and H2O mixing ratios simultaneously at 10 Hz. In addition, sensors for meteorological and geolocation data are incorporated into the system. The system is powered by car batteries with a low total power consumption (~200 W) and is easily transportable due to its low total mass (35 kg). Multiple measures have been taken to ensure robust performance of the custom, open-path sensors located on top of the vehicle where the optics are exposed to the harsh on-road environment. The mobile sensing system has been integrated and installed on top of common passenger vehicles and participated in extensive field campaigns (>400 h on-road time with >18,000 km total distance) in both the USA and China. The simultaneous detection of multiple trace gas species makes the mobile sensing platform a unique and powerful tool to identify and quantify different emission sources through mobile mapping.

  3. Greenhouse gases emissions accounting for typical sewage sludge digestion with energy utilization and residue land application in China

    SciTech Connect

    Niu Dongjie; Huang Hui; Dai Xiaohu; Zhao Youcai

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer GHGs emissions from sludge digestion + residue land use in China were calculated. Black-Right-Pointing-Pointer The AD unit contributes more than 97% of total biogenic GHGs emissions. Black-Right-Pointing-Pointer AD with methane recovery is attractive for sludge GHGs emissions reduction. - Abstract: About 20 million tonnes of sludge (with 80% moisture content) is discharged by the sewage treatment plants per year in China, which, if not treated properly, can be a significant source of greenhouse gases (GHGs) emissions. Anaerobic digestion is a conventional sewage sludge treatment method and will continue to be one of the main technologies in the following years. This research has taken into consideration GHGs emissions from typical processes of sludge thickening + anaerobic digestion + dewatering + residue land application in China. Fossil CO{sub 2}, biogenic CO{sub 2}, CH{sub 4,} and avoided CO{sub 2} as the main objects is discussed respectively. The results show that the total CO{sub 2}-eq is about 1133 kg/t DM (including the biogenic CO{sub 2}), while the net CO{sub 2}-eq is about 372 kg/t DM (excluding the biogenic CO{sub 2}). An anaerobic digestion unit as the main GHGs emission source occupies more than 91% CO{sub 2}-eq of the whole process. The use of biogas is important for achieving carbon dioxide emission reductions, which could reach about 24% of the total CO{sub 2}-eq reduction.

  4. [Soil greenhouse gases emission from an Acacia crassicarpa plantation under effects of understory removal and Cassia alata addition].

    PubMed

    Li, Hai-Fang; Zhang, Xing-Feng

    2010-03-01

    Forest soil is one of the main sources of greenhouse gases CO2, CH4, and N2O. By using static chamber and GS technique, this paper measured in situ the CO2, CH4, and N2O fluxes of Acacia crassicarpa plantation in Heshan Hilly Land Interdisciplinary Experimental Station under Chinese Academy of Sciences (CAS), and studied the soil CO2, CH4 and N2O emissions from the plantation under effects of understory removal and Cassia alata addition. The CO2 flux of the plantation maintained at a higher level during rainy season but decreased obviously in dry season, while the CH4 and N2O fluxes varied widely from September to November, with the peaks in October. Under the effects of understory removal and C. alata addition, the soil in the plantation could be a sink or a source of CH4, but consistently a source of CO2 and N2O. Understory removal enhanced the soil CO2 emission (P < 0.05 ), C. alata addition increased the soil CH4 emission (P < 0.05), while both understory removal and C. alata addition increased the soil N2O emission (P < 0.05). Surface soil temperature, moisture content, NO3(-) -N concentration, and microbial biomass carbon were the main factors affecting the soil CO2, CH4 and N2O emissions. PMID:20560308

  5. Measurement of Greenhouse gases (GHGs) and source apportionment in Bakersfield, CA during CalNex 2010

    NASA Astrophysics Data System (ADS)

    Guha, A.; Gentner, D. R.; Weber, R.; Gardner, A.; Provencal, R. A.; Goldstein, A. H.

    2011-12-01

    The California Global Warming Solutions Act 2006 (AB 32) creates a need to verify and validate the state GHG inventory, which is largely based on activity data and emission factor based estimates. The "bottom-up" emission factors for methane (CH4) and nitrous oxide (N2O) have large uncertainties and there is a lack of adequate "top-down" measurements to characterize emission rates from sources. Emissions from non-CO2 GHG sources display spatial heterogeneity and temporal variability, and are thus, often, poorly characterized. The Central Valley of California is an agriculture and industry intensive region with huge concentration of dairies, refineries and active oil fields which are known CH4 sources. As part of the CalNex campaign, we performed measurements of principal trace GHG gases (CO2, CH4, and N2O) and combustion tracer CO at the Bakersfield super-site during the summer of 2010. Measurements were made over a period of six weeks using fast response lasers based on cavity enhanced absorption spectroscopy (LGR Inc. CA). Coincident measurements of hundreds of volatile organic compounds (VOCs) served as anthropogenic and biogenic tracers of the GHG sources at local and regional levels. The local mean CH4 (1.93ppm) and N2O (325ppb) minimum are larger than that measured at Mauna Loa (NOAA). Daytime winds from the north-west draw emissions from the city center, Fruitvale oilfield and two refineries. Huge enhancements of CH4 relative to CO2 (> 4ppm of CH4) are seen on some days but almost on each night, when wind reversal and valley backflow brings winds from the east (oil fields and landfill). Winds from south-southwest (dairies) have ΔCH4 / ΔCO2 ratios similar to previous dairy chamber studies (Mitloehner et al., 2009). The ΔCH4 / ΔCO ratios at Bakersfield are much larger than that calculated downwind of Los Angeles at Mt. Wilson (Hsu et al., 2009) or in-flight measurements during CalNex (NOAA) suggesting additional non-combustion sources strongly influence

  6. Laser-based sensors on UAVs for quantifying local emissions of greenhouse gases

    NASA Astrophysics Data System (ADS)

    Zondlo, Mark; Tao, Lei; O'Brien, Anthony; Ross, Kevin; Khan, Amir; Pan, Da; Golston, Levi; Sun, Kang; DiGangi, Josh

    2015-04-01

    well above the surface (up to 100 m). In addition, plumes were very narrow horizontally (10-30 m width) within 200 m of the emission origin. By using a mass balance approach of upwind versus downwind CH4 concentrations, coupled to meteorological wind data, the CH4 emission rate from the compressor station averaged 13 ± 5 g CH4 s-1, consistent with individual, leak surveys measured within the compressor station itself. More recently, we developed a mid-infrared version of the same sensor using an antimonide laser at 3.3 microns. This sensor has a precision of 2 ppbv CH4 at 10 Hz, a mass of 1.3 kg, and consumes 10 W of power. Flight tests show the improved precision is capable of detecting methane leaks from landfills and cattle feedlots at higher altitudes (500 m) and greater distances downwind (several km) than the near infrared CH4 sensor. Sampling strategy is particularly important for not only UAS-based flight patterns but also sensor design. Many tradeoffs exist between the sampling density of the flight pattern, sensor precision, accuracy of wind data, and geographic isolation of the source of interest, and these will be discussed in the context of airborne-based CH4 measurements in the field. The development of compact yet robust trace gas sensors to be deployed on small UAS opens new capabilities for atmospheric sensing such as quantifying local source emissions (e.g. farms, well pads), vertical profiling of trace gases in a forest canopy, and trace gas distributions in complex areas (mountains, urban canyons).

  7. Intensive flux measurements and analysis of greenhouse gases from an upland cabbage field at Kunsan, Korea

    NASA Astrophysics Data System (ADS)

    Kim, D.; Na, U.

    2010-12-01

    significantly higher than those (negative value) during January (winter) when sub soil have low temperature and relatively high moisture due to snow during the winter measurement period. Averages of soil temperature and moisture during these months were 17.5±1.2oC, 45.7±8.2%WFPS for October; and 1.4±1.3oC, 89.9±8.8%WFPS for January. It may indicate that soil temperature and moisture have significant role in determining whether the CO2 and CH4 emission or uptake take place. Low temperature and high moisture above a certain optimum level during winter could weaken microbial activity and the gas diffusion in soil matrix, and then make soil GHG emission to the atmosphere decrease. Other soil parameters were also correlated with GHG emissions and discussed. Both positive and negative gas fluxes in CH4 and CO2 were observed during these measurements, but not for N2O. CH4 and CO2 gases seem to be emitted from soil surface or up taken by the soil depending on other factors such as background concentrations and physicochemical soil conditions. However, still there are many uncertainties and large scarcities in both their determination methods and soil GHG flux data. Improvement of measurement techniques and well-understanding of relationships between gas emission and controlling factors in such environments need to be required.

  8. Comparison of emission estimates for non-CO2 greenhouse gases from livestock and poultry in Korea from 1990 to 2010.

    PubMed

    Paik, Chunhyun; Chung, Yongjoo; Kim, Hugon; Kim, Young Jin

    2016-04-01

    It has often been claimed that non-carbon dioxide greenhouse gases (NCGGs), such as methane, nitrous oxide and fluorinated greenhouse gases, are significant contributors to climate change. Here we nvestigate emission estimates of methane and nitrous oxide from livestock and poultry production, which is recognized as a major source of those NCGGs, in Korea over the period of 1990 through 2010. Based on the data on livestock and poultry populations, emission estimates of methane and nitrous oxide are first derived based on the Tier 1 approach. Then, the Tier 2 approach is adopted to obtain emission estimates of methane and nitrous oxide from cattle, which are known to be the largest sources of these NCGGs and account for about 70% of emissions from livestock and poultry in Korea. The result indicates that the Tier 2 estimates of methane and nitrous oxide emissions from enteric fermentation and manure management are significantly different from the Tier 1 estimates over the analysis period. PMID:26419608

  9. A new aspect of the coupled ozone and nitrous oxide, and its implications for longterm changes in these two greenhouse gases

    NASA Astrophysics Data System (ADS)

    Prasad, S.

    The two greenhouses, N2O and O3 are currently thought to be quite independent, excepting that O(1D) from O3 photodissociation in the Hartley -Huggins band destroys N2O. A meta-analysis of the most recent and highly accurate laboratory determinations of the N2O quantum yields in UV (266 nm) photolysis of O3/O2/N2 mixtures (at 100 torr ≤ pressure ≤ 900 torr) shows that N2O is a byproduct of the way O3 shields the biosphere from the lethal ultraviolet. Thus, the two greenhouse gases, O3 and N2O, may not be truly independent in their origins; an increase in the atmospheric O3 may cause some increase in the N2O as well and complicate the estimation of the greenhouse effects of these two gages. These new developments will be discussed and the need of further laboratory studies will be identified.

  10. Spatial and Temporal Variation of Multiyear Sea Ice Distributions: Relationships among Melt Duration, Recruitment, Export, Clouds, and Greenhouse Gases

    NASA Astrophysics Data System (ADS)

    Belchansky, G. I.; Douglas, D. C.; Eremeev, V. A.; Platonov, N. G.

    2004-05-01

    We present the spatial and temporal variation of multiyear (MY) sea ice distributions: relationships among melt duration, recruitment, export, clouds, and greenhouse gases in the Arctic. Melt onset dates, freeze onset dates were estimated over Arctic sea-ice for the past 25-years using standardized SMMR-SSM/I data sets (1979-2002). Sea ice melt dynamics were compared between annual and perennial ice, and between different geographic regions. Average annual melt dates, freeze dates, and melt durations in annual ice were significantly correlated with seasonal strength of the Arctic oscillation (AO). Following high-index AO winters (January-March), spring melt tended to be earlier and autumn freeze later, leading to longer melt season durations. The largest increases in melt duration were observed in the eastern Siberian Arctic, coinciding with cyclonic low pressure and ice motion anomalies associated with the AO's high-index phase (1989-2002). In the northern Chukchi and East Siberian Seas, mean annual melt duration increased 2-3 weeks following the positive AO phase shift, compared to prior years (1979-1988). Different methods of MY sea ice inversions from SSM/I Tb data were compared using different multilayer perceptron (MLP) neural networks (NN) constructed with learning data based on ERS SAR and OKEAN-01 MY ice map products. Monthly Arctic MY sea ice concentration maps (1979 - 2003) were generated from SSM/I Tbs (19 GHz V, 19 GHz H and 37 GHz V) using a modified MLP with error back propagation, and then compared with respective MY sea ice concentration maps derived with the NASA Team algorithm. Three MLP NN ice-type classification methods utilizing SSM/I passive microwave data were originally developed and compared. Each used the same OKEAN-derived MY sea ice learning data, but each used a different learning algorithm: error back propagation with simulated annealing, dynamic learning with polynomial basis functions, and dynamic learning with two-step optimization

  11. Similarities in the Spatial Pattern of the Surface Flux Response to Present-Day Greenhouse Gases and Aerosols

    NASA Astrophysics Data System (ADS)

    Persad, G.; Ming, Y.; Ramaswamy, V.

    2014-12-01

    Recent studies suggest that present-day greenhouse gases (GHGs) and aerosols can produce remarkably similar patterns of climate response in fully coupled general circulation model (GCM) simulations, despite having significantly different spatial patterns of top-of-atmosphere (TOA) forcing. However, there is little understanding of the mechanisms of ocean-atmosphere interaction that could lead to the response pattern formation. Surface flux perturbations are a crucial pathway by which TOA forcing is communicated to the ocean, and may be a vital link in explaining the spatial similarities in the fully coupled responses to disparate TOA forcing patterns—a phenomenon with implications for detection and attribution, as well as the climate sensitivity to different forcers. We analyze the surface energy budget response to present-day aerosols versus GHGs in single forcing, fixed SST, atmospheric GCM experiments to identify mechanisms for response pattern formation via surface flux perturbations. We find that, although the TOA forcing spatial patterns of GHGs and aerosols are largely uncorrelated, their surface radiative and heat flux patterns are significantly anti-correlated. Furthermore, this anti-correlation is largely explained by similar (but sign-reversed) spatial patterns of surface latent and sensible heat flux response to the two forcers, particularly over the winter-hemisphere extratropical oceans. These are, in turn, driven by spatially similar perturbations in surface winds from changes in mean tropical and midlatitude circulation. These results suggest that the mean atmospheric circulation, which has many anti-symmetric responses to GHG and aerosol forcings, is an efficient homogenizer of spatial patterns in the surface heat flux response to heterogeneous TOA forcings, creating an atmosphere-only pathway for similarities in the fully coupled response.

  12. Ground-based demonstration of imaging SWIR-FTS for space-based detection of air pollution and greenhouse gases

    NASA Astrophysics Data System (ADS)

    Imai, Tadashi; Murooka, Jumpei; Kuze, Akihiko; Suto, Hiroshi; Sato, Ryota

    2013-10-01

    Fourier transform spectrometer (FTS) has many advantages, especially for greenhouse gases and air pollution detection in the atmosphere, because a single instrument can provide wide spectral coverage and high spectral resolution with highly stabilized instrumental line function for all wavenumbers. Several channels are usually required to derive the column amount or vertical profile of a target species. Near infrared (NIR) and shortwave infrared (SWIR) spectral regions are very attractive for remote sensing applications. The GHG and CO of precursors of air pollution have absorption lines in the SWIR region, and the sensitivity against change in the amounts in the boundary layer is high enough to measure mole fractions near the Earth surface. One disadvantage of conventional space-based FTS is the spatial density of effective observation. To improve the effective numbers of observations, an imaging FTS coupled with a two-dimensional (2D)-camera was considered. At first, a mercury cadmium telluride (MCT)-based imaging FTS was considered. However, an MCT-based system requires a calibration source (black body and deep-space view) and a highly accurate and super-low temperature control system for the MCT detector. As a result, size, weight, and power consumption are increased and the cost of the instrument becomes too high. To reduce the size, weight, power consumption, and cost, a commercial 2D indium gallium arsenide (InGaAs) camera can be used to detect SWIR light. To demonstrate a small imaging SWIR-FTS (IS-FTS), an imaging FTS coupled with a commercial 2D InGaAs camera was developed. In the demonstration, the CH4 gas cell was equipped with an IS-FTS for the absorber to make the spectra in the SWIR region. The spectra of CH4 of the IS-FTS demonstration model were then compared with those of traditional FTS. The spectral agreement between the traditional and IS-FTS instruments was very good.

  13. Spatial variations in immediate greenhouse gases and aerosol emissions and resulting radiative forcing from wildfires in interior Alaska

    NASA Astrophysics Data System (ADS)

    Huang, Shengli; Liu, Heping; Dahal, Devendra; Jin, Suming; Li, Shuang; Liu, Shuguang

    2016-02-01

    Boreal fires can cool the climate; however, this conclusion came from individual fires and may not represent the whole story. We hypothesize that the climatic impact of boreal fires depends on local landscape heterogeneity such as burn severity, prefire vegetation type, and soil properties. To test this hypothesis, spatially explicit emission of greenhouse gases (GHGs) and aerosols and their resulting radiative forcing are required as an important and necessary component towards a full assessment. In this study, we integrated remote sensing (Landsat and MODIS) and models (carbon consumption model, emission factors model, and radiative forcing model) to calculate the carbon consumption, GHGs and aerosol emissions, and their radiative forcing of 2001-2010 fires at 30 m resolution in the Yukon River Basin of Alaska. Total carbon consumption showed significant spatial variation, with a mean of 2,615 g C m-2 and a standard deviation of 2,589 g C m-2. The carbon consumption led to different amounts of GHGs and aerosol emissions, ranging from 593.26 Tg (CO2) to 0.16 Tg (N2O). When converted to equivalent CO2 based on global warming potential metric, the maximum 20 years equivalent CO2 was black carbon (713.77 Tg), and the lowest 20 years equivalent CO2 was organic carbon (-583.13 Tg). The resulting radiative forcing also showed significant spatial variation: CO2, CH4, and N2O can cause a 20-year mean radiative forcing of 7.41 W m-2 with a standard deviation of 2.87 W m-2. This emission forcing heterogeneity indicates that different boreal fires have different climatic impacts. When considering the spatial variation of other forcings, such as surface shortwave forcing, we may conclude that some boreal fires, especially boreal deciduous fires, can warm the climate.

  14. Tree specie effects on soil microbial community composition and greenhouse gases emissions in a Mediterranean ecotone forest

    NASA Astrophysics Data System (ADS)

    Fernandez, Maria Jose; Ortiz, Carlos; Kitzler, Barbara; Curiel, Jorge; Rubio, Agustin

    2016-04-01

    Over recent decades in the Iberian Peninsula, altitudinal shifts from Pinus sylvestris L. to Quercus pyrenaica Willd species has been observed as a consequence of Global Change, meaning changes in temperature, precipitation, land use and forestry. The forest conversion from pine to oak can alter the litter quality and quantity provided to the soil and thereby the soil microbial community composition and functioning. Since soil microbiota plays an important role in organic matter decomposition, and this in turn is key in biogeochemical cycles and forest ecosystems productivity, the rate in which forests produce and consume greenhouse gases can be also affected by changes in forest composition. In other words, changes in litter decomposition will ultimately affect downstream carbon and nitrogen dynamics although this impact is uncertain. In order to predict changes in carbon and nitrogen stocks in Global Change scenarios, it is necessary to deepen the impact of vegetation changes on soil microbial communities, litter decomposition dynamics (priming effect) and the underlying interactions between these factors. To test this, we conducted a full-factorial transplant microcosms experiment mixing both fresh soils and litter from Pyrenean oak, Scots pine and mixed stands collected inside their transitional area in Central Spain. The microcosms consisted in soil cylinders inside Kilner jars used as chambers inside an incubator. In this experiment, we investigated how and to what extent the addition of litter with different quality (needles, oak leaves and mixed needles-leaves) to soil inoculums with contrasting soil microbiota impact on (i) soil CO2, NO, N2O and CH4 efflux rates, (ii) total organic carbon and nitrogen and (iii) dissolved organic carbon and nitrogen. Furthermore, we assessed if these responses were controlled by changes in the microbial community structure using the PLFA analyses prior and after the incubation period of 54 days.

  15. Greenhouse Gases Life Cycle Assessment (GHGLCA) as a decision support tool for municipal solid waste management in Iran

    PubMed Central

    2014-01-01

    Background One of the most problems in developing countries is the integrated waste management and the effects on Greenhouse Gases (GHG) emission, Life Cycle Assessment (LCA) is used in this paper as a decision supporting tool in planning Municipal Solid Waste (MSW) managements. Methods In this paper the EPA’s Waste Reduction Model (WARM) that provide GHG emission factors for waste stream components that are based on life Cycle Inventory (LCI) framework were used and The MSW management methods comprised in seven scenarios. Results The amount of GHG which was generated from Iran’s waste sector estimated about 17836079 Metric Tons of Carbon dioxide Equivalents (MT CO2e) in this study. The lowest amount of GHG was generated by LFG capture system with energy recovery (557635 MT CO2e), while Incineration of materials being sent to landfill (1756823 MT CO2e), Landfill Gas (LFG) capture system with flaring (2929150 MT CO2e) and Improved source reduction and recycling (4780278 MT CO2e) emitted fewer GHG than the other scenarios. Lowest levels of gross energy consumption occur in source reduction with recycling and composting (-89356240 Mega British Thermal Unit, M BTU), recycling and composting (-86772060 M BTU) as well as Improved source reduction with recycling and composting (-54794888 M BTU). Conclusions It appears that recycling and composting each offer significant GHG emissions and energy consumption reductions (scenarios 4, 5 and 6). Upon of the GHG emission and energy consumption results concluded that improved source reduction and recycling scenario has been the Balanced and appropriate technology for handling the solid waste streams in municipalities. PMID:24910776

  16. Along-wind dispersion of short-duration accidental releases of hazardous gases

    SciTech Connect

    Hanna, S.R.

    1996-12-31

    Most accidental releases of hazardous gases are of short duration (a few minutes, at most) because of limitations to the total mass available for release or because of mitigation measures such as automatic valve closure or water spray curtains. The resulting cloud would then have the shape of an elongated puff at distances of about 500 m to 1,000 m when it encounters nearby population centers. The maximum concentration in the elongated puff depends strongly on whether the along-wind dispersion coefficient, {sigma}{sub x}, is larger than the length of the finite duration core of the cloud, u{sub c}T{sub d}, where T{sub d} is the source release duration and u{sub c} is the advective speed of the cloud. The along-wind dispersion coefficient, {sigma}{sub x}, is determined by the turbulent energy and the wind-shear over the cloud depth. Both the wind-shear and the advective speed of the cloud, u{sub c}, are functions of time or distance, since they represent concentration-weighted averages over the depth of the cloud, which is steadily increasing. Boundary-layer similarity theories are used to develop simplified formulas for {sigma}{sub x}, which are tested using data from laboratory and field experiments. The theory is expanded to include dense gas clouds and the resulting associated enhanced along-wind dispersion due to gravity slumping.

  17. Modern to millennium-old greenhouse gases emitted from ponds and lakes of the Eastern Canadian Arctic (Bylot Island, Nunavut)

    NASA Astrophysics Data System (ADS)

    Bouchard, F.; Laurion, I.; Prėskienis, V.; Fortier, D.; Xu, X.; Whiticar, M. J.

    2015-12-01

    Ponds and lakes are widespread across the rapidly changing permafrost environments. Aquatic systems play an important role in global biogeochemical cycles, especially in greenhouse gas (GHG) exchanges between terrestrial systems and the atmosphere. The source, speciation and emission rate of carbon released from permafrost landscapes are strongly influenced by local conditions, hindering pan-Arctic generalizations. This study reports on GHG ages and emission rates from aquatic systems located on Bylot Island, in the continuous permafrost zone of the Eastern Canadian Arctic. Dissolved and ebullition gas samples were collected during the summer season from different types of water bodies located in a highly dynamic periglacial valley: polygonal ponds, collapsed ice-wedge trough ponds, and larger lakes. The results showed strikingly different ages and fluxes depending on aquatic system types. Polygonal ponds were net sinks of dissolved CO2, but variable sources of dissolved CH4. They presented the highest ebullition fluxes, 1 or 2 orders of magnitude higher than from other ponds and lakes. Trough ponds appeared as substantial GHG sources, especially when their edges were actively eroding. Both types of ponds produced modern to hundreds of years old (< 550 yr BP) GHG, even if trough ponds could contain much older carbon (> 2000 yr BP) derived from freshly eroded peat. Lakes had small dissolved and ebullition fluxes, however they released much older GHG, including millennium-old CH4 (up to 3500 yr BP) from lake central areas. Acetoclastic methanogenesis dominated at all study sites and there was minimal, if any, methane oxidation in gas emitted through ebullition. These findings provide new insights on GHG emissions by permafrost aquatic systems and their potential positive feedback effect on climate.

  18. [Rules and impact factors of greenhouse gases emission in the saline-alkali paddy fields in different years].

    PubMed

    Tang, Jie; Fang, Tian-Ru; Hou, Ke-Yi; Zhao, Ren-Zhu; Liang, Shuang

    2014-12-01

    With the method of combining field sampling and plot test, we took saline-alkali paddy field of Qianguo county, Jilin province as an investigation object. According to the nature of soil in the area, we monitored CH4 and N2O which released from soil during rice growth period and tested the soil pH and soil organic carbon to analyze the law and reasons of greenhouse gas emission in the paddy fields. The results showed that N2O emission from paddy fields presented three peaks with distinct seasonal patterns. Application of fertilizer provided additional reactive substrate, which affected N2O emission significantly. Under flooding conditions, the main source of N2O is a denitrification process, while after drainage, nitrification was the predominance. CH4 emission showed a single peak at rice tillering stage when rice grew vigorously. That deoxidation condition dominated in the deep water layer in the paddy fields provided suitable conditions for CH4 producing microorganisms, which result in the emergence of CH4 emission peak. The pH doesn't have an obvious influence on CH4 and N2O, while SOC content in soil and pattern of CH4 emission showed a significantly positive correlation. PMID:25826947

  19. Microbial Consumption of Natural Gases Released from the BP Deepwater Horizon Oil Spill

    NASA Astrophysics Data System (ADS)

    Mendes, S. D.; Valentine, D. L.; Farwell, C.

    2010-12-01

    The BP Deepwater Horizon disaster caused the release of natural gas, which dissolved in the water column to form gas plumes. Containing methane, ethane, and propane, these gas plumes fuel microbial respiration. This work targeted the water column to quantify the maximum rate of microbial respiration in the natural gas plume. A novel method using uniformly 13C-labeled substrates as tracers was applied to determine the rate of microbial consumption of these gases in water surrounding the impacted area. Consumption rate experiments were performed on board the R/V Cape Hatteras (July 12-20, 2010) and analyzed using an isotope ratio mass spectrometer (IRMS). The kinetic order and maximum consumption rate of the microbial community were determined by experimental controls using the 13C-labeled tracers in temperature, time, and concentration series. Ongoing sampling efforts allow changes in the response of the microbial community to be monitored over time.

  20. Arctic greenhouse-gas storage and release modulated by late-glacial ice sheet fluctuations

    NASA Astrophysics Data System (ADS)

    Portnov, Alexey; Mienert, Jurgen; Vadakkepuliyambatta, Sunil; Patton, Henry; Andreassen, Karin; Winsborrow, Monica; Knies, Jochen; Hubbard, Alun I.

    2016-04-01

    The subglacial footprint of the Barents Sea Ice sheet which advanced across northern Eurasia from 26 to 22 ka BP had a major impact on the underlying gas hydrate stability zone (GHSZ) leading to storage of methane and other hydrocarbons. With the onset of deglaciation, these hydrocarbon rich hydrates dissociated, releasing potent greenhouse gas into the ocean and possibly atmosphere over a period of thousands of years. We present a wide-range of observational data acquired from offshore western Svalbard and the Barents Sea to robustly constrain a coupled model of the subglacial evolution of gas hydrate reservoirs during and after the Last Glacial Maximum (LGM). Our results indicate that even under minimum ice thickness reconstructions, an extensive, ~500-meter thick GHSZ existed beneath the ice sheet in our study area offshore of western Svalbard (Portnov et al., 2016). An offshore corridor of methane release did though also persist throughout maximum ice conditions on the upper continental margin. Throughout the LGM a marine ice sheet directly comparable to those of Greenland and Antarctica today inundated the continental margin offshore of western Svalbard and the vast shelf areas of the Barents Sea. However, with climatic amelioration the Barents Sea ice sheet experienced a 4ka period of dynamic retreat with concurrent flooding of the shelf by rising sea levels, which provided a high magnitude perturbation to the substrate pressure and temperature domains. By analogy, the future response of Polar ice sheets is an emerging concern as their ongoing thinning and retreat will likewise perturb the present day subglacial GHSZ leading to potential widespread gas hydrate destabilisation and release. Portnov, Alexey, et al. "Ice-sheet-driven methane storage and release in the Arctic", Nature Comm. DOI: 10.1038/ncomms10314. (2016).

  1. NOBLE GASES

    EPA Science Inventory

    The Noble Gases symposium, on which this report is based, provided comprehensive coverage of the noble gases. The coverage included, but was not limited to, the properties, biokinetics, bioeffects, production and release to the environment, detection techniques, standards, and ap...

  2. Noble Gases and Nitrogen Released from a Lunar Soil Pyroxene Separate by Acid Etching

    NASA Astrophysics Data System (ADS)

    Rider, P. E.

    1993-07-01

    We report initial results from a series of experiments designed to measure recently implanted solar wind (SW) ions in lunar soil mineral grains [1]. An acid-etching technique similar to the CSSE method developed at ETH Zurich was used to make abundance and isotope measurements of the SW noble gas and nitrogen compositions. Among the samples examined was a pyroxene separate from soil 75081. It was first washed with H2O to remove contamination from the sample finger walls and grain surfaces. H2O also acted as a weak acid, releasing gases from near-surface sites. Treatment with H2SO3 followed the water washes. Acid pH (~1.8 to ~1.0) and temperature (~23 degrees C to ~90 degrees C) and duration of acid attack (several minutes to several days) were varied from step to step. Finally, the sample was pyrolyzed in several steps to remove the remaining gases, culminating with a high-temperature pyrolysis at 1200 degrees C. Measurements of the light noble gases were mostly consistent with those from previous CSSE experiments performed on pyroxene [2,3]. It should be noted, however, that the Zurich SEP component was not easily distinguishable in the steps where it was expected to be observed. We suspect our experimental protocol masked the SEP reservoir, preventing us from seeing its distinctive signature. The most interesting results from this sample are its Kr and Xe isotopic and elemental compositions. Pyroxene apparently retains heavy noble gases as well as ilmenite (and plagioclase [4]). The heavy noble gas element ratios from this sample along with those previously reported [5,6] are, however, considerably heavier than the theoretically determined "solar system" values [7,8]. Explanations for the difference include the possibility that the derivations are incorrect, that there is another component of lunar origin mixing with the solar component, or that some type of loss mechanism is altering the noble gas reservoirs of the grains. The Kr and Xe isotopic compositions for

  3. Clear-cutting is causing large emissions of greenhouse gases - are there other harvest options that can avoid these emissions?

    NASA Astrophysics Data System (ADS)

    Lindroth, A.; Vestin, P.; Sundqvist, E.; Mölder, M.; Bâth, A.; Hellström, M.; Klemedtsson, L.; Weslien, P.

    2012-04-01

    Carbon sequestration in forests can potentially be enhanced through optimized forest management strategies and thus, mitigate climate change. However, carbon dioxide is not the only greenhouse gas (GHG) that is being exchanged between a forest ecosystem and the atmosphere; also methane and nitrous oxide are involved through different processes. A full assessment of the benefits of any management practice aiming at increasing the capacity of forests to mitigate climate change has to include all greenhouse gases. The effects of clear-cutting on GHG fluxes were studied at Norunda forest in central Sweden. Two different plots were established on a new clear-cut. Both plots were clear-cut (early 2009) and subsequently site prepared. On each of the plots, a 3 m high tower was erected and equipped for flux-gradient measurements of CO2, H2O, CH4 (May 2010 -) and N2O (June 2011 -). The clear-cut became waterlogged after harvest in 2009. One of the plots was significantly wetter than the other. All plots were on average sources of CO2, with daily average fluxes ranging between -2.5 and +5.8 µmol m¬-2s-1. The ingrowth of new vegetation was faster on the wetter plot, resulting in lower average CO2 emissions. Preliminary results indicate a switch from a weak CH4 sink to a significant CH4 source at both plots with higher emission from the wetter plot. Daily average CH4 fluxes ranged between -7.0 - +208.7 µmol m¬-2h-1. There were significant N2O emissions on all plots during the main growing season of 2011, with large emissions following heavy rain events. N2O fluxes ranged between -36.2 and +403.7 µg m¬-2h-1 but without clear differences between wetter and drier plots as in the case with CO2 and CH4. Although clear-cutting is the most common harvest method in Sweden today, other methods such as selective cutting are being increasingly discussed. We therefore studied the effects of thinning on soil and ecosystem carbon fluxes in the mature part of Norunda forest, located

  4. Greenhouse gases in the South Atlantic Ocean: recent trends and anomalies from continuous island and shipboard measurements

    NASA Astrophysics Data System (ADS)

    Lowry, David; Fisher, Rebecca; Lanoisellé, Mathias; France, James; Nisbet, Euan

    2013-04-01

    In-situ observation of tropical and southern Atlantic greenhouse gases is still limited. Continuous high-precision greenhouse gas measurement by CRDS in the South Atlantic started in 2010 on Ascension Is. (8° S) and near Stanley on East Falkland Is. (52° S), and in 2012 on the British Antarctic Survey ship RRS James Clark Ross, which sails annually from the UK to Antarctica and back. Both the Ascension and Falklands records show sustained inter-annual growth in both CO2 and CH4. NOAA data from a small number of stations indicate that Southern Tropical Methane has been increasing since 2007 but that growth is now slowing. This is confirmed by our new data. Strong CH4 growth of 11 ppb was observed on Ascension between July 2010 and July 2011 (winter to winter), of 7 ppb/yr from Jan 2011 to Jan 2012 (summer-to-summer) and decreased further to 4 ppb from July 2011 to July 2012. This compares with a fairly constant growth of 4-5 ppb/yr for the Falklands site. Isotopic evidence for the causes of the 2010-11 southern hemisphere sub-tropical methane anomaly is inconclusive. A slight depletion in 13C on Ascension during the period of growth might indicate that wetland emissions are the dominant cause of the anomaly, fitting with much higher than average sub-tropical rainfall during recent years, but a much longer data set is required to isolate the anomaly from the long-term trend. On 23 April 2011, Ascension experienced a 20-year event when the ITCZ moved far south of its normal position. In very clean marine air, in the space of 3 minutes the methane jumped from a normal autumn southern hemisphere level of 1763 ppb to 1795 ppb, closer to the concentrations of northern hemisphere spring, settling near to 1800 ppb for six hours, after which it rapidly fell back to 1760 ppb. Simultaneously CO2 rose from 389 to about 392 ppm, then to 396 ppm before falling back to 388 ppm. During this period there was very heavy rainfall, with nearly 300 mm on the slopes of Green Mountain

  5. Remote sensing of greenhouse gases (CO2 and CH4) using hyperspectral observations in the thermal infrared

    NASA Astrophysics Data System (ADS)

    Crevoisier, Cyril; Chedin, Alain; Nobileau, Delphine; Armante, Raymond; Thonat, Thibaud; Scott, Noelle A.

    ; (3) a latitudinal decrease from 20 N to 20 S lower than what is observed at the surface but in excellent agreement with tropospheric aircraft measurements; (4) geographical patterns in good agree-ment with simulations from atmospheric transport and chemistry models, but with a higher variability; (5) signatures of CO2 and CH4 emissions transported to the troposphere such as CO2 emissions from biomass burnings, or a large plume of elevated tropospheric methane south of the Asian continent, which might be due to Asian emissions from rice paddies uplifted by deep convection during the monsoon period and then transported towards Indonesia. More-over, these retrievals, performed from the same instrument and with the same retrieval process, provide the means to study the correlation between CO2 and CH4, in particular its seasonal variation over regions of specific interest, which leads the way to a multi-species study of surface fluxes and atmospheric transport. In addition to bringing a greatly improved view of CO2 and CH4 atmospheric distribution, these results from thermal infrared observations should provide a means to observe and understand atmospheric transport pathways of these two greenhouse gases from the surface to the upper troposphere.

  6. Estimation of the atmosphere-ocean fluxes of greenhouse gases and aerosols at the finer resolution of the coastal ocean.

    NASA Astrophysics Data System (ADS)

    Vieira, Vasco; Sahlée, Erik; Jurus, Pavel; Clementi, Emanuela; Pettersson, Heidi; Mateus, Marcos

    2016-04-01

    The balances and fluxes of greenhouse gases and aerosols between atmosphere and ocean are fundamental for Earth's heat budget. Hence, the scientific community needs to know and simulate them with accuracy in order to monitor climate change from Earth-Observation satellites and to produce reliable estimates of climate change using Earth-System Models (ESM). So far, ESM have represented earth's surface with coarser resolutions so that each cell of the marine domain is dominated by the open ocean. In such case it is enough to use simple algorithms considering the wind speed 10m above sea-surface (u10) as sole driver of the gas transfer velocity. The formulation by Wanninkhof (1992) is broadly accepted as the best. However, the ESM community is becoming increasingly aware of the need to model with finer resolutions. Then, it is no longer enough to only consider u10 when modelling gas transfer velocities across the coastal oceans' surfaces. More comprehensive formulations are required that adjust better to local conditions by also accounting for the effects of sea-surface agitation, wave breaking, atmospheric stability of the Surface Boundary Layer, current drag with the bottom, surfactants and rain. Accurate algorithms are also fundamental to monitor atmosphere and ocean greenhouse gas concentrations using satellite data and reverse modelling. Past satellite missions ERS, Envisat, Jason-2, Aqua, Terra and Metop, have already been remotely sensing the ocean's surface at much finer resolutions than ESM using instruments like MERIS, MODIS, AMR, AATSR, MIPAS, Poseidon-3, SCIAMACHY, SeaWiFS, and IASI. The planned new satellite missions Sentinel-3, OCO-2 and GOSAT will further increase the resolutions. We developed a framework to congregate competing formulations for the estimation of the solubility and transfer velocity of virtually any gas on the biosphere taking into consideration the atmosphere and ocean fundamental variables and their derived geophysical processes

  7. Variability of atmospheric greenhouse gases as a biogeochemical processing signal at regional scale in a karstic ecosystem

    NASA Astrophysics Data System (ADS)

    Borràs, Sílvia; Vazquez, Eusebi; Morguí, Josep-Anton; Àgueda, Alba; Batet, Oscar; Cañas, Lídia; Curcoll, Roger; Grossi, Claudia; Nofuentes, Manel; Occhipinti, Paola; Rodó, Xavier

    2015-04-01

    The South-eastern area of the Iberian Peninsula is an area where climatic conditions reach extreme climatic conditions during the year, and is also heavily affected by the ENSO and NAO. The Natural Park of Cazorla, Segura de la Sierra and Las Villas is located in this region, and it is the largest protected natural area in Spain (209920 Ha). This area is characterized by important climatic and hydrologic contrasts: although the mean annual precipitation is 770 nm, the karstic soils are the main cause for water scarcity during the summer months, while on the other hand it is in this area where the two main rivers of Southern Spain, the Segura and the Guadalquivir, are born. The protected area comprises many forested landscapes, karstic areas and reservoirs like Tranco de Beas. The temperatures during summer are high, with over 40°C heatwaves occurring each year. But during the winter months, the land surface can be covered by snow for periods of time up until 30 days. The ENSO and NAO influences cause also an important inter annual climatic variability in this area. Under the ENSO, autumnal periods are more humid while the following spring is drier. In this area vegetal Mediterranean communities are dominant. But there are also a high number of endemic species and derelict species typical of temperate climate. Therefore it is a protected area with high specific diversity. Additionally, there is an important agricultural activity in the fringe areas of the Natural Park, mainly for olive production, while inside the Park this activity is focused on mountain wheat production. Therefore the diverse vegetal communities and landscapes can easily be under extreme climatic pressures, affecting in turn the biogeochemical processes at the regional scale. The constant, high-frequency monitoring of greenhouse gases (GHG) (CO2 and CH4) integrates the biogeochemical signal of changes in this area related to the carbon cycle at the regional scale, capturing the high diversity of

  8. Profiling Wind and Greenhouse Gases by Infrared-laser Occultation: Algorithm and Results from Simulations in Windy Air

    NASA Astrophysics Data System (ADS)

    Plach, Andreas; Proschek, Veronika; Kirchengast, Gottfried

    2014-05-01

    We employ the Low Earth Orbit (LEO-LEO) microwave and infrared-laser occultation (LMIO) method to derive a full set of thermodynamic state variables from microwave signals and climate benchmark profiling of greenhouse gases (GHGs) and line-of-sight (l.o.s.) wind using infrared-laser signals. The focus lies on the upper troposphere/lower stratosphere region (UTLS - 5 km to 35 km). The GHG retrieval errors are generally smaller than 1% to 3% r.m.s., at a vertical resolution of about 1 km. In this study we focus on the infrared-laser part of LMIO, where we introduce a new, advanced wind retrieval algorithm to derive accurate l.o.s. wind profiles. The wind retrieval uses the reasonable assumption of the wind blowing along spherical shells (horizontal winds) and therefore the l.o.s. wind speed can be retrieved by using an Abel integral transform. A 'delta-differential transmission' principle is applied to two thoroughly selected infrared-laser signals placed at the wings of the highly symmetric C18OO absorption line (nominally ±0.004 cm-1 from the line center near 4767 cm-1) plus a related 'off-line' reference signal. The delta-differential transmission obtained by differencing these signals is clear from atmospheric broadband effects and is proportional to the wind-induced Doppler shift; it serves as the integrand of the Abel transform. The Doppler frequency shift calculated along with the wind retrieval is in turn also used in the GHG retrieval to correct the frequency of GHG-sensitive infrared-laser signals for the wind-induced Doppler shift, which enables improved GHG estimation. This step therefore provides the capability to correct potential wind-induced residual errors of the GHG retrieval in case of strong winds. We performed end-to-end simulations to test the performance of the new retrieval in windy air. The simulations used realistic atmospheric conditions (thermodynamic state variables and wind profiles) from an analysis field of the European Centre for

  9. Nonlinear response of modelled stratospheric ozone to changes in greenhouse gases and ozone depleting substances in the recent past

    NASA Astrophysics Data System (ADS)

    Meul, S.; Oberländer-Hayn, S.; Abalichin, J.; Langematz, U.

    2015-06-01

    In the recent past, the evolution of stratospheric ozone (O3) was affected by both increasing ozone depleting substances (ODSs) and greenhouse gases (GHGs). The impact of the single forcings on O3 is well known. Interactions between the simultaneously increased GHG and ODS concentrations, however, can occur and lead to nonlinear O3 changes. In this study, we investigate if nonlinear processes have affected O3 changes between 1960 and 2000. This is done with an idealised set of time slice simulations with the chemistry-climate model EMAC. Due to nonlinearity the past ozone loss is diminished throughout the stratosphere, with a maximum reduction of 1.2 % at 3 hPa. The total ozone column loss between 1960 and 2000 that is mainly attributed to the ODS increase is mitigated in the extra-polar regions by up to 1.1 % due to nonlinear processes. A separation of the O3 changes into the contribution from chemistry and transport shows that nonlinear interactions occur in both. In the upper stratosphere a reduced efficiency of the ClOx-catalysed O3 loss chiefly causes the nonlinear O3 increase. An enhanced formation of halogen reservoir species through the reaction with methane (CH4) reduces the abundance of halogen radicals significantly. The temperature-induced deceleration of the O3 loss reaction rate in the Chapman cycle is reduced, which leads to a nonlinear O3 decrease and counteracts the increase due to ClOx. Nonlinear effects on the NOx abundance cause hemispheric asymmetric nonlinear changes of the O3 loss. Nonlinear changes in O3 transport occur in particular in the Southern Hemisphere (SH) during the months September to November. Here, the residual circulation is weakened in the lower stratosphere, which goes along with a reduced O3 transport from the tropics to high latitudes. Thus, O3 decreases in the SH polar region but increases in the SH midlatitudes. The existence of nonlinearities implies that future ozone change due to ODS decline slightly depends on the

  10. Airborne measurements and emission estimates of greenhouse gases and other trace constituents from the 2013 California Yosemite Rim wildfire

    NASA Astrophysics Data System (ADS)

    Yates, E. L.; Iraci, L. T.; Singh, H. B.; Tanaka, T.; Roby, M. C.; Hamill, P.; Clements, C. B.; Lareau, N.; Contezac, J.; Blake, D. R.; Simpson, I. J.; Wisthaler, A.; Mikoviny, T.; Diskin, G. S.; Beyersdorf, A. J.; Choi, Y.; Ryerson, T. B.; Jimenez, J. L.; Campuzano-Jost, P.; Loewenstein, M.; Gore, W.

    2016-02-01

    This paper presents airborne measurements of multiple atmospheric trace constituents including greenhouse gases (such as CO2, CH4, O3) and biomass burning tracers (such as CO, CH3CN) downwind of an exceptionally large wildfire. In summer 2013, the Rim wildfire, ignited just west of the Yosemite National Park, California, and burned over 250,000 acres of the forest during the 2-month period (17 August to 24 October) before it was extinguished. The Rim wildfire plume was intercepted by flights carried out by the NASA Ames Alpha Jet Atmospheric eXperiment (AJAX) on 29 August and the NASA DC-8, as part of SEAC4RS (Studies of Emissions, Atmospheric Composition, Clouds and Climate Coupling by Regional Surveys), on 26 and 27 August during its intense, primary burning period. AJAX revisited the wildfire on 10 September when the conditions were increasingly smoldering, with slower growth. The more extensive payload of the DC-8 helped to bridge key measurements that were not available as part of AJAX (e. g. CO). Data analyses are presented in terms of emission ratios (ER), emission factors (EF) and combustion efficiency and are compared with previous wildfire studies. ERs were 8.0 ppb CH4 (ppm CO2)-1 on 26 August, 6.5 ppb CH4 (ppm CO2)-1 on 29 August and 18.3 ppb CH4 (ppm CO2)-1 on 10 September 2013. The increase in CH4 ER from 6.5 to 8.0 ppb CH4 (ppm CO2)-1 during the primary burning period to 18.3 ppb CH4 (ppm CO2)-1 during the fire's slower growth period likely indicates enhanced CH4 emissions from increased smoldering combustion relative to flaming combustion. Given the magnitude of the Rim wildfire, the impacts it had on regional air quality and the limited sampling of wildfire emissions in the western United States to date, this study provides a valuable dataset to support forestry and regional air quality management, including observations of ERs of a wide number of species from the Rim wildfire.

  11. Sugarcane field renovation: influence of tillage and no-tillage in the emission of greenhouse gases (GHG).

    NASA Astrophysics Data System (ADS)

    Packer, Ana Paula; Degaspari, Iracema A. M.; Ramos, Nilza Patricia; Vilela, Viviane A. A.; do Carmo, Janaina B.; Cabral, Osvaldo M. R.; Rossi, Paulo; de Andrade, Cristiano A.

    2015-04-01

    The management of agricultural soils can play an important role in the greenhouse gases (GHG) balance, depending on the adopted practices. In the agricultural system, current GHG emissions generated by anthropogenic activities include land use, land use change and management practices, which have contributed to disrupt the C and N cycles in terrestrial ecosystems. The GHG (CO2, N2O and CH4) emissions from agricultural soils depend on the biophysical processes, and the incorporation/decomposition of organic residues. Agricultural soils preparation requires a combination of several implements, which can produce great soil disturbance as is the case of conventional tillage or minimum soil mobilization in the reduced tillage or no-tillage. Tillage breaks soil aggregates leading to enhanced organic matter decomposition and reduced C and N concentrations and no-tillage increases the stability of soil macroaggregates, reducing the emissions of CO2. In this study, we evaluated the CO2 emissions from different management practices widely used in the renewal of sugarcane fields previously planted with soybean, in an Acric Oxisol plantation in the southeast region of Brazil. The conventional tillage (CT) operation consisted of an offset disk harrowing using a tool with 36 disks x 26" and a subsoiling with an implement reaching nearly 50 cm depth. The reduced tillage (RT) was carried out with subsoiling operation in the row planting and in the no-tillage (NT), the soybean trash from the last harvest was left on the soil. The soil preparation and the establishment of four experimental plots (30 m x 30 m each) occurred within two days. During the studied period, two CO2 and N2O emission peaks were observed after the soil preparation, the first one on day 4 and the second on day 35 after a 55 mm rain. The cumulative emissions were measured during 40 days after soil preparation. We observed higher emissions in the conventional tillage (CT), and lower values in the reduced tillage

  12. Spatial variations in immediate greenhouse gases and aerosol emissions and resulting radiative forcing from wildfires in interior Alaska

    USGS Publications Warehouse

    Huang, Shengli; Liu, Heping; Dahal, Devendra; Jin, Suming; Li, Shuang; Liu, Shu-Guang

    2016-01-01

    Boreal fires can cool the climate; however, this conclusion came from individual fires and may not represent the whole story. We hypothesize that the climatic impact of boreal fires depends on local landscape heterogeneity such as burn severity, prefire vegetation type, and soil properties. To test this hypothesis, spatially explicit emission of greenhouse gases (GHGs) and aerosols and their resulting radiative forcing are required as an important and necessary component towards a full assessment. In this study, we integrated remote sensing (Landsat and MODIS) and models (carbon consumption model, emission factors model, and radiative forcing model) to calculate the carbon consumption, GHGs and aerosol emissions, and their radiative forcing of 2001–2010 fires at 30 m resolution in the Yukon River Basin of Alaska. Total carbon consumption showed significant spatial variation, with a mean of 2,615 g C m−2 and a standard deviation of 2,589 g C m−2. The carbon consumption led to different amounts of GHGs and aerosol emissions, ranging from 593.26 Tg (CO2) to 0.16 Tg (N2O). When converted to equivalent CO2 based on global warming potential metric, the maximum 20 years equivalent CO2 was black carbon (713.77 Tg), and the lowest 20 years equivalent CO2 was organic carbon (−583.13 Tg). The resulting radiative forcing also showed significant spatial variation: CO2, CH4, and N2O can cause a 20-year mean radiative forcing of 7.41 W m−2 with a standard deviation of 2.87 W m−2. This emission forcing heterogeneity indicates that different boreal fires have different climatic impacts. When considering the spatial variation of other forcings, such as surface shortwave forcing, we may conclude that some boreal fires, especially boreal deciduous fires, can warm the climate.

  13. Future Climate Impacts of Direct Radiative Forcing Anthropogenic Aerosols, Tropospheric Ozone, and Long-lived Greenhouse Gases

    NASA Technical Reports Server (NTRS)

    Chen, Wei-Ting; Liao, Hong; Seinfeld, John H.

    2007-01-01

    Long-lived greenhouse gases (GHGs) are the most important driver of climate change over the next century. Aerosols and tropospheric ozone (O3) are expected to induce significant perturbations to the GHG-forced climate. To distinguish the equilibrium climate responses to changes in direct radiative forcing of anthropogenic aerosols, tropospheric ozone, and GHG between present day and year 2100, four 80-year equilibrium climates are simulated using a unified tropospheric chemistry-aerosol model within the Goddard Institute for Space Studies (GISS) general circulation model (GCM) 110. Concentrations of sulfate, nitrate, primary organic (POA) carbon, secondary organic (SOA) carbon, black carbon (BC) aerosols, and tropospheric ozone for present day and year 2100 are obtained a priori by coupled chemistry-aerosol GCM simulations, with emissions of aerosols, ozone, and precursors based on the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenario (SRES) A2. Changing anthropogenic aerosols, tropospheric ozone, and GHG from present day to year 2100 is predicted to perturb the global annual mean radiative forcing by +0.18 (considering aerosol direct effects only), +0.65, and +6.54 W m(sup -2) at the tropopause, and to induce an equilibrium global annual mean surface temperature change of +0.14, +0.32, and +5.31 K, respectively, with the largest temperature response occurring at northern high latitudes. Anthropogenic aerosols, through their direct effect, are predicted to alter the Hadley circulation owing to an increasing interhemispheric temperature gradient, leading to changes in tropical precipitation. When changes in both aerosols and tropospheric ozone are considered, the predicted patterns of change in global circulation and the hydrological cycle are similar to those induced by aerosols alone. GHG-induced climate changes, such as amplified warming over high latitudes, weakened Hadley circulation, and increasing precipitation over the

  14. Forests on drained agricultural peatland are potentially large sources of greenhouse gases - insights from a full rotation period simulation

    NASA Astrophysics Data System (ADS)

    He, Hongxing; Jansson, Per-Erik; Svensson, Magnus; Björklund, Jesper; Tarvainen, Lasse; Klemedtsson, Leif; Kasimir, Åsa

    2016-04-01

    The CoupModel was used to simulate a Norway spruce forest on fertile drained peat over 60 years, from planting in 1951 until 2011, describing abiotic, biotic and greenhouse gas (GHG) emissions (CO2 and N2O). By calibrating the model against tree ring data a "vegetation fitted" model was obtained by which we were able to describe the fluxes and controlling factors over the 60 years. We discuss some conceptual issues relevant to improving the model in order to better understand peat soil simulations. However, the present model was able to describe the most important ecosystem dynamics such as the plant biomass development and GHG emissions. The GHG fluxes are composed of two important quantities, the spruce forest carbon (C) uptake, 413 g C m-2 yr-1 and the decomposition of peat soil, 399 g C m-2 yr-1. N2O emissions contribute to the GHG emissions by up to 0.7 g N m-2 yr-1, corresponding to 76 g C m-2 yr-1. The 60-year old spruce forest has an accumulated biomass of 16.0 kg C m-2 (corresponding to 60 kg CO2 m-2). However, over this period, 26.4 kg C m-2 (97 kg CO2eq m-2) has been added to the atmosphere, as both CO2 and N2O originating from the peat soil and, indirectly, from forest thinning products, which we assume have a short lifetime. We conclude that after harvest at an age of 80 years, most of the stored biomass carbon is liable to be released, the system having captured C only temporarily and with a cost of disappeared peat, adding CO2 to the atmosphere.

  15. Forests on drained agricultural peatland are potentially large sources of greenhouse gases - insights from a full rotation period simulation

    NASA Astrophysics Data System (ADS)

    He, H.; Jansson, P.-E.; Svensson, M.; Björklund, J.; Tarvainen, L.; Klemedtsson, L.; Kasimir, Å.

    2015-12-01

    The CoupModel was used to simulate a Norway Spruce forest on fertile drained peat over 60 years, from planting in 1951 until 2011, describing abiotic, biotic and greenhouse gas (GHG) emissions (CO2 and N2O). By calibrating the model against tree ring data we obtained a "reference" model by which we were able to describe the fluxes and controlling factors over the 60 years. We discuss some conceptual issues relevant to improving the model in order to better understand peat soil simulations. However, the present model was able to describe the most important ecosystem dynamics such as the plant biomass development and GHG emissions. The GHG fluxes are composed of two important quantities, the forest carbon (C) uptake, 405 g C m-2 yr-1 and the decomposition of peat soil, 396 g C m-2 yr-1. N2O emissions contribute to the GHG emissions by 0.5 g N m-2 yr-1, corresponding to 56.8 g C m-2 yr-1. The 60-year-old Spruce forest has an accumulated biomass of 164 Mg C ha-1. However, over this period 208 Mg C ha-1 GHG has been added to the atmosphere, which means a net addition of GHG emissions. The main losses are from the peat soil and, indirectly, from forest thinning products, which we assume have a short lifetime. We conclude that after harvest at an age of 80 years, most of the stored biomass carbon is liable to be released, the system having captured C only temporarily and with a cost of disappeared peat, adding CO2 to the atmosphere.

  16. Forests on drained agricultural peatland are potentially large sources of greenhouse gases - insights from a full rotation period simulation

    NASA Astrophysics Data System (ADS)

    He, Hongxing; Jansson, Per-Erik; Svensson, Magnus; Björklund, Jesper; Tarvainen, Lasse; Klemedtsson, Leif; Kasimir, Åsa

    2016-04-01

    The CoupModel was used to simulate a Norway Spruce forest on fertile drained peat over 60 years, from planting in 1951 until 2011, describing abiotic, biotic and greenhouse gas (GHG) emissions (CO2 and N2O). By calibrating the model against tree ring derived biomass data and measured 6 year abiotic data we obtained a "reference" model by which we were able to describe the GHG fluxes and controlling factors over the 60 years. The GHG fluxes are composed of two important quantities, the forest carbon (C) uptake, 405 g C m‑2 yr‑1 and the decomposition of peat soil, 396 g C m‑2 yr‑1. N2O emissions contribute to the GHG emissions by 0.5 g N m‑2 yr‑1, corresponding to 56.8 g C m‑2 yr‑1. The 60-year-old Spruce forest has an accumulated biomass of 164 Mg C ha‑1. However, over this period 208 Mg C ha‑1 GHG has been added to the atmosphere, which means a net addition of GHG emissions. The main losses are from the peat soil and, indirectly, from forest thinning products, which we assume have a short lifetime. Model sensitivity analysis by changing initial soil C, drainage depth and initial soil C/N ratio also confirms that forests on drained agricultural peatland are a GHG source. We conclude that after harvest at an age of 80 years, most of the stored biomass carbon is liable to be released, the system having captured C only temporarily and with a cost of disappeared peat, adding both CO2 and N2O to the atmosphere.

  17. Effect of cattle urine addition on the surface emissions and subsurface concentrations of greenhouse gases from a UK lowland peatland.

    NASA Astrophysics Data System (ADS)

    Boon, Alex; Robinson, Steve; Chadwick, David; Cardenas, Laura

    2014-05-01

    no effect of treatment on subsurface CO2 concentrations. Subsurface N2O peaked at 500ppm 12 days after and 1200ppm 56 days after application. Subsurface NO3- concentration peaked at approximately 300 mg N kg dry soil-112 days after application. Results indicate that denitrification is the key driver for N2O release in peatlands and that production is strongly related to increased soil moisture. N2O production at depth continued long after emissions were detected at the surface. Increased study of the interaction between subsurface gas concentrations, surface emissions and soil hydrological conditions is required to successfully predict greenhouse gas production and emission.

  18. Dispersion modeling of accidental releases of toxic gases - Sensitivity study and optimization of the meteorological input

    NASA Astrophysics Data System (ADS)

    Baumann-Stanzer, K.; Stenzel, S.

    2009-04-01

    Several air dispersion models are available for prediction and simulation of the hazard areas associated with accidental releases of toxic gases. The most model packages (commercial or free of charge) include a chemical database, an intuitive graphical user interface (GUI) and automated graphical output for effective presentation of results. The models are designed especially for analyzing different accidental toxic release scenarios ("worst-case scenarios"), preparing emergency response plans and optimal countermeasures as well as for real-time risk assessment and management. Uncertainties in the meteorological input together with incorrect estimates of the source play a critical role for the model results. The research project RETOMOD (reference scenarios calculations for toxic gas releases - model systems and their utility for the fire brigade) was conducted by the Central Institute for Meteorology and Geodynamics (ZAMG) in cooperation with the Vienna fire brigade, OMV Refining & Marketing GmbH and Synex Ries & Greßlehner GmbH. RETOMOD was funded by the KIRAS safety research program at the Austrian Ministry of Transport, Innovation and Technology (www.kiras.at). The main tasks of this project were 1. Sensitivity study and optimization of the meteorological input for modeling of the hazard areas (human exposure) during the accidental toxic releases. 2. Comparison of several model packages (based on reference scenarios) in order to estimate the utility for the fire brigades. This presentation gives a short introduction to the project and presents the results of task 1 (meteorological input). The results of task 2 are presented by Stenzel and Baumann-Stanzer in this session. For the aim of this project, the observation-based analysis and forecasting system INCA, developed in the Central Institute for Meteorology and Geodynamics (ZAMG) was used. INCA (Integrated Nowcasting through Comprehensive Analysis) data were calculated with 1 km horizontal resolution and

  19. Tree species influence soil-atmosphere fluxes of the greenhouse gases CO2, CH4 and N2O

    NASA Astrophysics Data System (ADS)

    Steffens, Christina; Vesterdal, Lars; Pfeiffer, Eva-Maria

    2016-04-01

    In the temperate zone, forests are the greatest terrestrial sink for atmospheric CO2, and tree species affect soil C stocks and soil CO2 emissions. When considering the total greenhouse gas (GHG) balance of the forest soil, the relevant GHGs CH4 and N2O should also be considered as they have a higher global warming potential than CO2. The presented data are first results from a field study in a common garden site in Denmark where tree species with ectomycorrhizal colonization (beech - Fagus sylvatica, oak - Quercus robur) and with arbuscular mycorrhizal colonization (maple - Acer pseudoplatanus, ash - Fraxinus excelsior) have been planted in monocultures in adjacent blocks of about 0.25 ha in the year 1973 on former arable land. The soil-atmosphere fluxes of all three gases were measured every second week since August 2015. The hypothesis is that the total GHG efflux from forest soil would differ between species, and that these differences could be related to the type of mycorrhizal association and leaf litter quality. Preliminary results (August to December 2015) indicate that tree species influence the fluxes (converted to CO2-eq) of the three GHGs. Total soil CO2 efflux was in the low end of the range reported for temperate broadleaved forests but similar to the measurements at the same site approximately ten years ago. It was highest under oak (9.6±2.4 g CO2 m‑2 d‑1) and lowest under maple (5.2±1.6 g CO2 m‑2 d‑1). In contrast, soil under oak was a small but significant sink for CH4(-0.005±0.003 g CO2-eq m‑2 d‑1), while there were almost no detectable CH4 fluxes in maple. Emissions of N2O were highest under beech (0.6±0.6 g CO2-eq m‑2 d‑1) and oak (0.2±0.09 g CO2-eq m‑2 d‑1) and lowest under ash (0.03±0.04 g CO2-eq m‑2 d‑1). In the total GHG balance, soil CH4 uptake was negligible (≤0.1% of total emissions). Emissions of N2O (converted to CO2-eq) contributed <1% (ash) to 8% (beech) to total GHG emissions. Summing up all GHG

  20. Releases of refrigerant gases (CFC-12, HCFC-22 and HFC-134a) to the atmosphere

    NASA Astrophysics Data System (ADS)

    McCulloch, Archie; Midgley, Pauline M.; Ashford, Paul

    Two of the gases, CFC-12 (dichlorodifluoromethane, CF 2Cl 2) and HCFC-22 (chlorodifluoromethane, CHClF 2) have long histories of emission from refrigeration and other uses. Production and sales records show the expected fall in the amounts of CFC-12 used in refrigeration after the Montreal Protocol came into effect but this does not seem to have been accompanied by significant substitution by HCFC-22, demand for which appears governed by organic growth. HFC-134a (1,1,1,2-tetrafluoroethane, CH 2FCF 3) is a relative newcomer that has partially substituted for CFC-12. After developing a single data set for the global use of each substance in refrigeration, foam blowing and aerosol propulsion, and other promptly emissive uses, annual releases of the compounds were estimated by applying emission functions derived from surveying both the producers of the chemicals and the principal industrial users. For CFC-12 and HFC-134a, atmospheric concentrations calculated from the emissions estimated here are in good agreement with observations, verifying that the emission functions adequately describe the relationship between the quantities in use, the atmospheric lifetimes of 100 and 14.6 years, respectively, and the extent of release into the atmosphere. The agreement between observation and calculation is poorer for HCFC-22, if its atmospheric lifetime is 12 years, but becomes much closer with a lifetime of 10 years. An 80% reduction in CFC requirement has been substituted only to the extent of 25% by HFC-134a. This is consistent with improved technology to curtail leakage and so enable lower system charges that, in turn, translate into less demand. For the same reason, the refrigeration emission function for HFC-134a over the period 1990-2000 was not significantly different from that of CFC-12. The lower absolute rate of leakage and lower absolute charge sizes combining to maintain a similar relative rate of loss.

  1. Combustion Gases And Heat Release Analysis During Flame And Flameless Combustion Of Wood Pellets

    NASA Astrophysics Data System (ADS)

    Horváth, Jozef; Wachter, Igor; Balog, Karol

    2015-06-01

    With the growing prices of fossil fuels, alternative fuels produced of biomass come to the fore. They are made of waste materials derived from the processing of wood and wood materials. The main objective of this study was to analyse the fire-technical characteristics of wood pellets. The study analysed three dust samples acquired from wood pellets made of various types of wood biomass. Wood pellet dust is produced when manipulating with pellets. During this process a potentially hazardous situations may occur. Biomass is chemically composed mostly of hemicellulose, cellulose and lignin. During straining of the biomass by heat flux, combustion initiation occurs. Also, there was a change in the composition of material throughout combustion gases production, and the amount of heat generated by a flame or flameless combustion. Measurement of fire characteristics was conducted according to ISO 5660-1 standard using a cone calorimeter. Two samples of wood pellet dust were tested under the heat flux of 35 kW.m-2 and 50 kW.m-2. The process of combustion, the time to ignition, the carbon monoxide concentration and the amount of released heat were observed.

  2. Influence of meteorology and interrelationship with greenhouse gases (CO2 and CH4) at a sub-urban site of India

    NASA Astrophysics Data System (ADS)

    Sreenivas, G.; Mahesh, P.; Subin, J.; Kanchana, A. L.; Rao, P. V. N.; Dadhwal, V. K.

    2015-12-01

    Atmospheric greenhouse gases (GHGs) such as carbon dioxide (CO2) and methane (CH4) are important climate forcing agents due to their significant impact on the climate system. The present study brings out first continuous measurements of atmospheric GHG's using high precision Los Gatos Research's-greenhouse gas analyser (LGR-GGA) over Shadnagar, a suburban site of Central India during the period 2014. The annual mean of CO2 and CH4 over the study region is found to be 394 ± 2.92 and 1.92 ± 0.07 ppm (mean, μ ± 1 SD, σ) respectively. CO2 and CH4 showed a significant seasonal variation during the study period with maximum (minimum) CO2 observed during Pre-monsoon (Monsoon), while CH4 recorded maximum during post-monsoon and minimum in monsoon. A consistent diurnal mixing ratio of these gases is observed with high (low) during night (afternoon) hours throughout the study period. Influences of prevailing meteorology (air temperature, wind speed, wind direction and relative humidity) on GHG's have also been investigated. CO2 and CH4 showed a strong positive correlation during winter, pre-monsoon, monsoon and post-monsoon with R equal to 0.80, 0.80, 0.61 and 0.72 respectively. It implies the seasonal variations in source-sink mechanisms of CO2 and CH4. Present study also confirms implicitly the presence OH radicals as a major sink of CH4 over the study region.

  3. Biogeochemistry, transport fluxes and emission of greenhouse gases from the Ogooué River (west central Africa): preliminary results after two years of monitoring

    NASA Astrophysics Data System (ADS)

    Darchambeau, François; Bouillon, Steven; Mbega, Jean-Daniel; Lambert, Thibault; Borges, Alberto V.

    2014-05-01

    The Ogooué River is the fourth largest river in Africa by discharge. The Ogooué Basin mostly consists of undisturbed rainforest with some savanna grassland. Yet, there is no information on the biogeochemistry, transport fluxes and greenhouse gases in this river. Here, we report initial results of a monitoring campaign whereby 2-weekly samples were collected at Lambaréné (Gabon) [10.24°E 0.69°S] between April 2012 and March 2014 for a suite of physico-chemical and biogeochemical characteristics, including total suspended matter (TSM) concentrations, concentration and stable isotope composition of particulate organic carbon (POC and δ13C-POC) and particulate nitrogen (PN and δ15N-PN), chromophoric dissolved organic matter (CDOM), dissolved organic carbon (DOC and δ13C-DOC), dissolved inorganic carbon (DIC and δ13C-DIC), concentration of greenhouse gases (GHGs) (CO2, CH4 and N2O), as well as major elements, total alkalinity, and oxygen isotope signatures of water (δ18O-H2O). This dataset allows us to construct annual budgets for particulate and dissolved carbon fluxes, nutrient exports, as well as a first seasonally resolved characterisation of the GHGs emitted to the atmosphere by the Ogooué River.

  4. Effects of ploughing on land-atmosphere exchange of greenhouse gases in a managed temperate grassland in central Scotland

    NASA Astrophysics Data System (ADS)

    Helfter, Carole; Drewer, Julia; Anderson, Margaret; Scholtes, Bob; Rees, Bob; Skiba, Ute

    2015-04-01

    Grasslands are important ecosystems covering > 20% and > 30% of EU and Scotland's land area respectively. Management practices such as grazing, fertilisation and ploughing can have significant short- and long-term effects on greenhouse gas exchange. Here we report on two separate ploughing events two years apart in adjacent grasslands under common management. The Easter Bush grassland, located 10 km south of Edinburgh (55° 52'N, 3° 2'W), comprises two fields separated by a fence and is used for grazing by sheep and cattle. The vegetation is predominantly Lolium perenne (> 90%) growing on poorly drained clay loam. The fields receive several applications of mineral fertiliser a year in spring and summer. Net ecosystem exchange (NEE) of carbon dioxide (CO2) has been monitored continuously by eddy-covariance (EC) since 2002 which has demonstrated that the site is a consistent yet variable sink of atmospheric CO2. The EC system comprises a LI-COR 7000 closed-path analyser and a Gill Instruments Windmaster Pro ultrasonic anemometer mounted atop a 2.5 m mast located along the fence line separating the fields. In addition, fluxes of nitrous oxide (N2O), methane (CH4)and CO2were measured with static chambers installed along transects in each field. Gas samples collected from the chambers were analysed by gas chromatography and fluxes calculated for each 60-minute sampling period. The ploughing events in 2012 and 2014 exhibited multiple similarities in terms of NEE. The light response (i.e. relationship between CO2 flux, and photosynthetically active radiation, PAR) of the NF and SF during the month preceding each ploughing event was of comparable magnitude in both years. Following ploughing, CO2 uptake ceased in the ploughed field for approximately one month and full recovery of the photosynthetic potential was observed after ca. 2 months. During the month following the 2014 ploughing event, the ploughed NF released on average 333 ± 17 mg CO2-C m-2 h-1. In contrast, the

  5. Dispersion modeling of accidental releases of toxic gases - utility for the fire brigades.

    NASA Astrophysics Data System (ADS)

    Stenzel, S.; Baumann-Stanzer, K.

    2009-09-01

    Several air dispersion models are available for prediction and simulation of the hazard areas associated with accidental releases of toxic gases. The most model packages (commercial or free of charge) include a chemical database, an intuitive graphical user interface (GUI) and automated graphical output for effective presentation of results. The models are designed especially for analyzing different accidental toxic release scenarios ("worst-case scenarios”), preparing emergency response plans and optimal countermeasures as well as for real-time risk assessment and management. The research project RETOMOD (reference scenarios calculations for toxic gas releases - model systems and their utility for the fire brigade) was conducted by the Central Institute for Meteorology and Geodynamics (ZAMG) in cooperation with the Viennese fire brigade, OMV Refining & Marketing GmbH and Synex Ries & Greßlehner GmbH. RETOMOD was funded by the KIRAS safety research program of the Austrian Ministry of Transport, Innovation and Technology (www.kiras.at). The main tasks of this project were 1. Sensitivity study and optimization of the meteorological input for modeling of the hazard areas (human exposure) during the accidental toxic releases. 2. Comparison of several model packages (based on reference scenarios) in order to estimate the utility for the fire brigades. For the purpose of our study the following models were tested and compared: ALOHA (Areal Location of Hazardous atmosphere, EPA), MEMPLEX (Keudel av-Technik GmbH), Trace (Safer System), Breeze (Trinity Consulting), SAM (Engineering office Lohmeyer). A set of reference scenarios for Chlorine, Ammoniac, Butane and Petrol were proceed, with the models above, in order to predict and estimate the human exposure during the event. Furthermore, the application of the observation-based analysis and forecasting system INCA, developed in the Central Institute for Meteorology and Geodynamics (ZAMG) in case of toxic release was

  6. Preface to book entitled: Managing Agricultural Greenhouse Gases: Coordinated Agricultural Research through GRACEnet to Address our Changing Climate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Atmospheric greenhouse gas (GHG) absorbs and emits radiation within the thermal infrared range, a natural process that regulates the temperature of the Earth. Long-term changes in GHG emission could negatively or positively affect global surface temperature (USGCRP, 2009). The abatement of climate...

  7. The Role of Long-Lived Greenhouse Gases as Principal LW Control Knob that Governs the Global Surface Temperature for Past and Future Climate Change

    NASA Technical Reports Server (NTRS)

    Lacis, Andrew A.; Hansen, James E.; Russell, Gary L.; Oinas, Valdar; Jonas, Jeffrey

    2013-01-01

    The climate system of the Earth is endowed with a moderately strong greenhouse effect that is characterized by non-condensing greenhouse gases (GHGs) that provide the core radiative forcing. Of these, the most important is atmospheric CO2. There is a strong feedback contribution to the greenhouse effect by water vapor and clouds that is unique in the solar system, exceeding the core radiative forcing due to the non-condensing GHGs by a factor of three. The significance of the non-condensing GHGs is that once they have been injected into the atmosphere, they remain there virtually indefinitely because they do not condense and precipitate from the atmosphere, their chemical removal time ranging from decades to millennia. Water vapor and clouds have only a short lifespan, with their distribution determined by the locally prevailing meteorological conditions, subject to Clausius-Clapeyron constraint. Although solar irradiance is the ultimate energy source that powers the terrestrial greenhouse effect, there has been no discernible long-term trend in solar irradiance since precise monitoring began in the late 1970s. This leaves atmospheric CO2 as the effective control knob driving the current global warming trend. Over geological time scales, volcanoes are the principal source of atmospheric CO2, and the weathering of rocks is the principal sink, with the biosphere participating as both a source and a sink. The problem at hand is that human industrial activity is causing atmospheric CO2, to increase by 2 ppm per year, whereas the interglacial rate has been 0.005 ppm per year. This is a geologically unprecedented rate to turn the CO2 climate control knob. This is causing the global warming that threatens the global environment.

  8. Small scale controls of greenhouse gas release under elevated N deposition rates in a restoring peat bog in NW Germany

    NASA Astrophysics Data System (ADS)

    Glatzel, S.; Forbrich, I.; Krüger, C.; Lemke, S.; Gerold, G.

    2008-06-01

    In Central Europe, most bogs have a history of drainage and many of them are currently being restored. Success of restoration as well as greenhouse gas exchange of these bogs is influenced by environmental stress factors as drought and atmospheric nitrogen deposition. We determined the methane and nitrous oxide exchange of sites in the strongly decomposed center and less decomposed edge of the Pietzmoor bog in NW Germany in 2004. Also, we examined the methane and nitrous oxide exchange of mesocosms from the center and edge before, during, and following a drainage experiment as well as carbon dioxide release from disturbed unfertilized and nitrogen fertilized surface peat. In the field, methane fluxes ranged from 0 to 3.8 mg m-2 h-1 and were highest from hollows. Field nitrous oxide fluxes ranged from 0 to 574 μg m-2 h-1 and were elevated at the edge. A large Eriophorum vaginatum tussock showed decreasing nitrous oxide release as the season progressed. Drainage of mesocosms decreased methane release to 0, even during rewetting. There was a tendency for a decrease of nitrous oxide release during drainage and for an increase in nitrous oxide release during rewetting. Nitrogen fertilization did not increase decomposition of surface peat. Our examinations suggest a competition between vascular vegetation and denitrifiers for excess nitrogen. We also provide evidence that the von Post humification index can be used to explain nitrous oxide release from bogs, if the role of vascular vegetation is also considered. An assessment of the greenhouse gas release from nitrogen saturated restoring bogs needs to take into account elevated release from fresh Sphagnum peat as well as from sedges growing on decomposed peat. Given the high atmospheric nitrogen deposition, restoration will not be able to achieve an oligotrophic ecosystem in the short term.

  9. FETC Programs for Reducing Greenhouse Gas Emissions

    SciTech Connect

    Ruether, J.A.

    1998-02-01

    Mark Twain once quipped that everyone talks about the weather but no one does anything about it. With interest in global climate change on the rise, researchers in the fossil-energy sector are feeling the heat to provide new technology to permit continued use of fossil fuels but with reduced emissions of so-called `greenhouse gases.` Three important greenhouse gases, carbon dioxide, methane, and nitrous oxide, are released to the atmosphere in the course of recovering and combusting fossil fuels. Their importance for trapping radiation, called forcing, is in the order given. In this report, we briefly review how greenhouse gases cause forcing and why this has a warming effect on the Earth`s atmosphere. Then we discuss programs underway at FETC that are aimed at reducing emissions of methane and carbon dioxide.

  10. A new interactive chemistry-climate model: 2. Sensitivity of the middle atmosphere to ozone depletion and increase in greenhouse gases and implications for recent stratospheric cooling

    NASA Astrophysics Data System (ADS)

    Manzini, E.; Steil, B.; Brühl, C.; Giorgetta, M. A.; Krüger, K.

    2003-07-01

    The sensitivity of the middle atmosphere circulation to ozone depletion and increase in greenhouse gases is assessed by performing multiyear simulations with a chemistry-climate model. Three simulations with fixed boundary conditions have been carried out: one simulation for the near-past (1960) and two simulations for the near-present (1990 and 2000) conditions, including changes in greenhouse gases, in total organic chlorine, and in average sea surface temperatures. Changes in ozone are simulated interactively by the coupled model. It is found that in the stratosphere, ozone decreases, and that in the Antarctic, the ozone hole develops in both the 1990 and the 2000 simulations but not in the 1960 simulation, as observed. The simulated temperature decreases in the stratosphere and mesosphere from the near past to the present, with the largest changes at the stratopause and at the South Pole in the lower stratosphere, in agreement with current knowledge of temperature trends. In the Arctic lower stratosphere, a cooling in March with respect to the 1960 simulation is found only for the 2000 simulation. Wave activity emerging from the troposphere is found to be comparable in the winters of the 1960 and 2000 simulations, suggesting that ozone depletion and greenhouse gases increase contribute to the 2000-1960 March cooling in the Arctic lower stratosphere. These results therefore provide support to the interpretation that the extreme low temperatures observed in March in the last decade can arise from radiative and chemical processes, although other factors cannot be ruled out. The comparison of the 1960 and 2000 simulations shows an increase in downwelling in the mesosphere at the time of cooling in the lower stratosphere (in March in the Arctic; in October in the Antarctic). The mesospheric increase in downwelling can be explained as the response of the gravity waves to the stronger winds associated with the cooling in the lower stratosphere. Planetary waves appear

  11. Sensitivity of the Climate to Changes in Solar Irradiance, Orbital Forcing and Greenhouse Gases During the Maunder Minimum From a Suite of GCM Experiments

    NASA Astrophysics Data System (ADS)

    Waple, A. M.; DeConto, R. M.; Bradley, R. S.

    2002-05-01

    Equilibrium model experiments have been run with the GENESIS AGCM version 2.0 (Pollard and Thompson 1995b) to examine sensitivity of the climate to a variety of possible forcing scenarios during the Maunder Minimum (~1675), present-day and ~2050AD. Solar irradiance, orbital forcing and greenhouse gases were incrementally added in a suite of experiments to determine the relative effects of each individual forcing as well as the combined response. If solar irradiance is reduced to Maunder Minimum-estimated values (maintaining present-day greenhouse gases and orbital forcing), globally averaged temperature is cooler than present, as expected, and though the GCM does not have a coupled ocean, it does have a coupled sea-ice model and sea-ice feedbacks dominate the high-latitude response pattern. Especially large near-surface temperature responses are seen in the areas of Greenland and the Weddell Sea. Naturally, the sea-ice feedback leads to a marked seasonality of response, but there are substantial differences in the seasonal response in the tropics as well as at high latitudes. The model results indicate that a shift in the ITCZ position contributes to this temperature difference as well as substantial precipitation changes. Consistent with a cooler climate, precipitation is also moderately reduced relative to present. In addition, an increase in the meridionality of circulation, which has been suggested as a more persistent pattern of circulation for the Little Ice Age (eg. Wanner 1994), is evident when solar irradiance is reduced to estimated Maunder Minimum values in these model experiments. During all three model time-periods, including the Maunder Minimum, orbital forcing plays a larger role than expected, especially at high-latitudes. The forcing is of the opposite sign to that induced by solar variability over this time-frame, therefore moderately tempers the effect of lower solar irradiance during the Maunder Minimum. Greenhouse gases also play a large role

  12. Space-Based Measurements of CO2 from the Japanese Greenhouse Gases Observing Satellite (GOSAT) and the NASA Orbiting Carbon Observatory-2 (OCO-2) Missions

    NASA Technical Reports Server (NTRS)

    Crisp, David

    2011-01-01

    Space-based remote sensing observations hold substantial promise for future long-term monitoring of CO2 and other greenhouse gases. The principal advantages of space based measurements include: (1) Spatial coverage (especially over oceans and tropical land) (2) Sampling density (needed to resolve CO2 weather). The principal challenge is the need for high precision To reach their full potential, space based CO2 measurements must be validated against surface measurements to ensure their accuracy. The TCCON network is providing the transfer standard There is a need for a long-term vision to establish and address community priorities (1) Must incorporate ground, air, space-based assets and models (2) Must balance calls for new observations with need to maintain climate data records.

  13. Distinguishing the impacts of ozone-depleting substances and well-mixed greenhouse gases on Arctic stratospheric ozone and temperature trends

    NASA Astrophysics Data System (ADS)

    Rieder, Harald E.; Polvani, Lorenzo M.; Solomon, Susan

    2014-04-01

    Whether stratospheric cooling due to increases in well-mixed greenhouse gases (WMGHG) could increase the depletion of Arctic stratospheric ozone has been the subject of scientific and public attention for decades. Here we provide evidence that changes in the concentrations of ozone-depleting substances (ODS), not WMGHG, have been the primary driver of observed Arctic lower stratospheric trends in both ozone and temperature. We do so by analyzing polar cap ozone and temperature trends in reanalysis data: these clearly suggest that both trends are mainly driven by ODS in the lower stratosphere. This observation-based finding is supported by results from a stratosphere-resolving chemistry-climate model driven with time-varying ODS and WMGHG, specified in isolation and in combination. Taken together, these results provide strong evidence that ODS are the main driver of changes in the Arctic lower stratospheric temperatures and ozone, whereas WMGHG are the primary driver of changes in the upper stratosphere.

  14. CO2 retrieval algorithm for the thermal infrared spectra of the Greenhouse Gases Observing Satellite: Potential of retrieving CO2 vertical profile from high-resolution FTS sensor

    NASA Astrophysics Data System (ADS)

    Saitoh, Naoko; Imasu, Ryoichi; Ota, Yoshifumi; Niwa, Yosuke

    2009-09-01

    The Greenhouse Gases Observing Satellite (GOSAT) was successfully launched in January 2009, with the aim of providing global observations of greenhouse gases. We developed an algorithm to retrieve CO2 vertical profiles from the terrestrial radiation spectra at 700-800 cm-1 and assessed its validity. For this purpose, we first computed GOSAT pseudomeasurement spectra and then performed CO2 retrieval simulations using the maximum a posteriori (MAP) method, with analytical data for temperature information. Our simulations with no uncertainty in the estimates of atmospheric conditions such as surface temperature, surface emissivity, and profiles of temperature, water vapor, and ozone showed that the retrieved CO2 profiles had an accuracy of 1% above 800 hPa, with little dependence on the a priori profiles. Introducing correlations between layers in an a priori error covariance matrix was important for CO2 retrieval especially above 200 hPa. Enhancing the correlations below 800 hPa was important for CO2 retrieval there. Selecting 100 channels based on CO2 information content for all layers, 10 channels for the region above 55 hPa, and 50 channels for the region below 800 hPa was sufficient to achieve CO2 retrieval with 1% accuracy from the troposphere through the stratosphere. Our simulations with possible errors in the atmospheric conditions showed that 1% accuracy was also achieved at 600-100 hPa in every latitude region, although the retrieved CO2 concentrations probably included up to 4% positive and negative biases at 30°S-30°N above 100 hPa and at mid- and high latitudes below 600 hPa, respectively.

  15. Release of noble gases and nitrogen from grain-surface sites in lunar ilmenite by closed-system oxidation

    NASA Technical Reports Server (NTRS)

    Frick, U.; Becker, R. H.; Pepin, R. O.

    1986-01-01

    Noble gases and nitrogen were extracted from a 100 to 150 microns ilmenite separate from lunar soil 71501 by closed system stepped heating in approx. 10 torr O2 at 300 C, 400 C, 500 C, 600 C and 630 C, followed by stepped pyrolysis at ten temperatures between 680 C and approx. 1500 C. The five oxidation steps together liberated approx. 65% of the total He-4, 45% of the Ne-20, 23% of the N-14 and Ar-36, 12% of the Kr-84 and 8% of the Xe-132 in the sample; Ne-20/Ar-36 and Ne-20/Ne-22 ratios agree with the solar wind composition experiment, and Kr-84/Ar-36 and Xe-132/Ar-36 are within approx. 10% of Cameron's estimates for the sun and solar wind. The remaining gases, released above 630 C by pyrolysis, are strongly fractionated with respect to the SWC-Cameron solar wind elemental composition. Large concentrations of fractionated noble gases in grain interiors, their virtual absence in the relatively unfractionated surface gas reservoir, and the high N/noble gas ratio all imply that most of the solar wind noble gases initially implanted in grain surfaces are eventually lost by diffusion. Loss limits can be estimated by considering two given scenarios. It is concluded tat approx. 70 to 97% or more of the Ar implanted in 71501 ilmenite grains has diffusively escaped.

  16. Screening of inorganic gases released from firework-rockets by a gas chromatography/whistle-accelerometer method.

    PubMed

    Chen, Kuan-Fu; Wu, Hui-Hsin; Lin, Chien-Hung; Lin, Cheng-Huang

    2013-08-30

    The use of an accelerometer for detecting inorganic gases in gas chromatography (GC) is described. A milli-whistle was connected to the outlet of the GC capillary and was used instead of a classical GC detector. When the GC carrier gases and the sample gases pass through the milli-whistle, a sound is produced, leading to vibrational changes, which can be recorded using an accelerometer. Inorganic gases, including SO2, N2 and CO2, which are released from traditional Chinese firework-rockets at relatively high levels as the result of burning the propellant and explosive material inside could be rapidly determined using the GC/whistle-accelerometer system. The method described herein is safe, the instrumentation is compact and has potential to be modified so as to be portable for use in the field. It also can be used in conjunction with FID (flame ionization detector) or TCD (thermal conductivity detector), in which either no response for FID (CO2, N2, NO2, SO2, etc.) or helium gas is needed for TCD, respectively. PMID:23891209

  17. A comparative study of vertical flow and free-water surface constructed wetlands for low C/N ratio domestic wastewater treatment and its greenhouse gases emission

    NASA Astrophysics Data System (ADS)

    Xu, K.; Liu, C.; Ebie, Y.; Inamori, Y.

    2008-12-01

    Constructed wetland (CW) systems are reliable, flexible in design, and can be built, operated, and maintained at lower costs compared to conventional methods of chemical treatment. Therefore, CW systems are widely used for controlling water-body eutrophication as an ease-operation and cost-effective ecological technology in developing countries. However, growing attention has been directed to its greenhouse side-effect and global-warming potential in recent years. In this study, two typical constructed wetlands: Vertical flow (VF) and Free-water surface (FWS) constructed wetlands were used not only to compare the nutrients removal performance for treatment of low C/N ratio loading domestic wastewater, but also to investigate and compare their CH4 and N2O greenhouse gases emission characteristics. The results indicated that the VF CW showed a comparatively good performance for nitrogen and phosphorus removal than FWS constructed wetland, which was 98.5, 95.9, 93.2 and 90.7 percent for BOD5, SS, NH4-N and TP under 6 days HRT, respectively. It was found that the FWS CW had the higher tendency to emit CH4 than the VF CW during four seasons of one year.

  18. Impact of biodiesel and renewable diesel on emissions of regulated pollutants and greenhouse gases on a 2000 heavy duty diesel truck

    NASA Astrophysics Data System (ADS)

    Na, Kwangsam; Biswas, Subhasis; Robertson, William; Sahay, Keshav; Okamoto, Robert; Mitchell, Alexander; Lemieux, Sharon

    2015-04-01

    As part of a broad evaluation of the environmental impacts of biodiesel and renewable diesel as alternative motor fuels and fuel blends in California, the California Air Resources Board's (CARB) Heavy-duty Diesel Emission Testing Laboratory conducted chassis dynamometer exhaust emission measurements on in-use heavy-heavy-duty diesel trucks (HHDDT). The results presented here detail the impact of biodiesel and renewable diesel fuels and fuel blends as compared to CARB ULSD on particulate matter (PM), regulated gases, and two greenhouse gases emissions from a HHDDT with a 2000 C15 Caterpillar engine with no exhaust after treatment devices. This vehicle was tested over the Urban Dynamometer Driving Schedule (UDDS) and the cruise portion of the California HHDDT driving schedule. Three neat blend stocks (soy-based and animal-based fatty acid methyl ester (FAME) biodiesels, and a renewable diesel) and CARB-certified ultra-low sulfur diesel (CARB ULSD) along with their 20% and 50% blends (blended with CARB ULSD) were tested. The effects of blend level on emission characteristics were discussed on g·km-1 basis. The results showed that PM, total hydrocarbon (THC), and carbon monoxide (CO) emissions were dependent on driving cycles, showing higher emissions for the UDDS cycles with medium load than the highway cruise cycle with high load on per km basis. When comparing CARB ULSD to biodiesels and renewable diesel blends, it was observed that the PM, THC, and CO emissions decreased with increasing blend levels regardless of the driving cycles. Note that biodiesel blends showed higher degree of emission reductions for PM, THC, and CO than renewable diesel blends. Both biodiesels and renewable diesel blends effectively reduced PM emissions, mainly due to reduction in elemental carbon emissions (EC), however no readily apparent reductions in organic carbon (OC) emissions were observed. When compared to CARB ULSD, soy- and animal-based biodiesel blends showed statistically

  19. Renewable Energy Production and Urban Remediation: Modeling the biogeochemical cycle at contaminated urban brownfields and the potential for renewable energy production and mitigation of greenhouse gases

    NASA Astrophysics Data System (ADS)

    Gopalakrishnan, G.

    2014-12-01

    greenhouse gas emissions are explored. Tradeoffs between renewable energy production,contaminant removal, and mitigation of greenhouse gases are also evaluated. Results indicate that a decrease in greenhouse gas emissions of 29-43% is possible, together with an estimated increase in renewable energy production of 7-22%.

  20. In-situ release of solar wind gases from lunar soil. [H2 and helium-3 collection

    NASA Technical Reports Server (NTRS)

    Wittenberg, Layton J.

    1992-01-01

    A concept is described which has the potential to perform the in situ heating of the lunar regolith in order to release the solar wind gases. The poor thermal conductivity of the lunar soil is increased approximately 100-fold by the introduction of an artificial hydrogen atmosphere at 1 atm pressure enclosed in an inflatable structure. The leakage rate of H2 through the soil is minimal because of the close-packed nature of the soil and the design and operation of the facility.

  1. Accelerated greenhouse gases versus slow insolation forcing induced climate changes in southern South America since the Mid-Holocene

    NASA Astrophysics Data System (ADS)

    Berman, Ana Laura; Silvestri, Gabriel E.; Rojas, Maisa; Tonello, Marcela S.

    2016-03-01

    This paper is a pioneering analysis of past climates in southern South America combining multiproxy reconstructions and the state-of-the-art CMIP5/PMIP3 paleoclimatic models to investigate the time evolution of regional climatic conditions from the Mid-Holocene (MH) to the present. This analysis allows a comparison between the impact of the long term climate variations associated with insolation changes and the more recent effects of anthropogenic forcing on the region. The PMIP3 multimodel experiments suggest that changes in precipitation over almost all southern South America between MH and pre-industrial (PI) times due to insolation variations are significantly larger than those between PI and the present, which are due to changes in greenhouse gas concentrations. Anthropogenic forcing has been particularly intense over western Patagonia inducing reduction of precipitation in summer, autumn and winter as a consequence of progressively weaker westerly winds over the region, which have moved further poleward, between ca. 35-55°S and have become stronger south of about 50°S. Orbital variations between the MH to the PI period increased insolation over southern South America during summer and autumn inducing warmer conditions in the PI, accentuated by the effect of anthropogenic forcing during the last century. On the other hand, changes in orbital parameters from the MH to the PI period reduced insolation during winter and spring inducing colder conditions, which have been reversed by the anthropogenic forcing.

  2. Measurements and modeling of greenhouse gases and the planetary boundary layer for the Boston metro area and the Northeastern Megalopolis

    NASA Astrophysics Data System (ADS)

    DeCola, Philip; Jones, Taylor; Wofsy, Steven; McKain, Kathryn; Chen, Jia; Bererra, Yanina; Gottlieb, Elaine; Nehrkorn, Thomas; Hegarty, Jennifer; Eluszkiewicz, Janusz; Henderson, John; Mountain, Marikate; Hutyra, Lucy; Callahan, William

    2014-05-01

    The accuracy of greenhouse gas (GHG) emission and air quality simulations reflects the fidelity of the atmospheric transport model employed that in turn is highly dependent on the accuracy of the meteorological input data. We begin by describing a multi-scale measurement network and model-data analysis framework for the Boston Metro region, with extension to the mid-Atlantic urban corridor. Observations include a network of automated concentrations of CO2 and CH4 inside and outside the urban domain, near the surface, on towers and tall buildings, total column measurements using the sun as a source, aerosol LiDAR data defining atmospheric structure, and meteorological data. The model-data analysis framework includes a Lagrangian particle dispersion model (LPDM), the Stochastic Time-Inverted Lagrangian Transport (STILT), driven by meteorological fields from the North American Regional Reanalysis (NARR) and Weather Research and Forecasting (WRF) model, and an inversion framework. We show examples of data and discuss the observational network's sampling design and a plan for extension to the NE urban corridor of the US. These urban studies are demonstrating the feasibility and value of incorporating advanced instrumentation such as the Mini Micro Pulse LiDAR to evaluate and improve the fidelity of the WRF simulations of atmospheric transport and structure in the planetary boundary layer. We also present examples of inverse analyses assessing anthropogenic emission rates for CH4 and CO2 in the urban region of metro Boston and along the urban-rural gradient.

  3. The natural flux of greenhouse gases in the case of monitoring the flux of juvenile carbon dioxide in the Hranice Karst

    NASA Astrophysics Data System (ADS)

    Geršl, Milan; Stepišnik, Uroš; Mareček, Jan; Geršlová, Eva; Hammerschmiedt, Michal

    2015-04-01

    Located in the Teplice nad Bečvou district 40 km SE of Olomouc (Czech Republic), the hydrothermal Hranice Karst with the Zbrašov Aragonite Caves has been developed in the sequence of Palaeozoic limestones as a result of deep influx of thermal water charged with subcrustal carbon dioxide (CO2). This area of discharge of juvenile carbon dioxide is a unique place where one can study the long-term natural production of a greenhouse gas and confront it with the anthropogenic production. As a result, the continuous measurements of the properties of the cave microclimate with additional seasonal measurements of flux of carbon dioxide give rise to a rare pool of data that cover natural routes of greenhouse gases. Repeated seasonal analysis of the ratio of stable carbon isotopes in carbon dioxide (d13C around -5 ) (Meyberg - Rinne, 1995)has suggested the juvenile (mantle) origin of this gas. Isotopic analyses in the mineral water of dissolved gases (He) show that some part of these gases come from the upper mantle of the Earth. The lower floors of the caves are filled with carbon dioxide producing so-called gas lakes in the area. Concentrations of the gas commonly reach 40 % by volume. In 1999, for example, the average concentration in the Gallas dome was 84.9 % by volume. Flux of CO2 (g.m-2.d-1) was measured on the surface and in the cave. The homogenisation chamber and the pumping test were applied to evaluate the CO2 flux. The average CO2 flux in the soil ranged from 74 to 125 g.m-2.d-1, reflecting the venting of subcrustal CO2 in the Hranice area (Geršl et al., 2012). In the Zbrašov Aragonite Caves the CO2 concentration in the atmosphere fluctuates from 0,X to 85 % with the measured constant flux being 32 894 g.m-2.d-1. Since 2005, the CO2 concentrations in the cave area have been reported by an automatic monitoring system at 10 cave sites. CO2 concentrations are recorded in 5-min intervals. Interpretation can be put into the context of measuring concentrations of

  4. Development and integration of a solar powered unmanned aerial vehicle and a wireless sensor network to monitor greenhouse gases.

    PubMed

    Malaver, Alexander; Motta, Nunzio; Corke, Peter; Gonzalez, Felipe

    2015-01-01

    Measuring gases for environmental monitoring is a demanding task that requires long periods of observation and large numbers of sensors. Wireless Sensor Networks (WSNs) and Unmanned Aerial Vehicles (UAVs) currently represent the best alternative to monitor large, remote, and difficult access areas, as these technologies have the possibility of carrying specialized gas sensing systems. This paper presents the development and integration of a WSN and an UAV powered by solar energy in order to enhance their functionality and broader their applications. A gas sensing system implementing nanostructured metal oxide (MOX) and non-dispersive infrared sensors was developed to measure concentrations of CH4 and CO2. Laboratory, bench and field testing results demonstrate the capability of UAV to capture, analyze and geo-locate a gas sample during flight operations. The field testing integrated ground sensor nodes and the UAV to measure CO2 concentration at ground and low aerial altitudes, simultaneously. Data collected during the mission was transmitted in real time to a central node for analysis and 3D mapping of the target gas. The results highlights the accomplishment of the first flight mission of a solar powered UAV equipped with a CO2 sensing system integrated with a WSN. The system provides an effective 3D monitoring and can be used in a wide range of environmental applications such as agriculture, bushfires, mining studies, zoology and botanical studies using a ubiquitous low cost technology. PMID:25679312

  5. Development and Integration of a Solar Powered Unmanned Aerial Vehicle and a Wireless Sensor Network to Monitor Greenhouse Gases

    PubMed Central

    Malaver, Alexander; Motta, Nunzio; Corke, Peter; Gonzalez, Felipe

    2015-01-01

    Measuring gases for environmental monitoring is a demanding task that requires long periods of observation and large numbers of sensors. Wireless Sensor Networks (WSNs) and Unmanned Aerial Vehicles (UAVs) currently represent the best alternative to monitor large, remote, and difficult access areas, as these technologies have the possibility of carrying specialized gas sensing systems. This paper presents the development and integration of a WSN and an UAV powered by solar energy in order to enhance their functionality and broader their applications. A gas sensing system implementing nanostructured metal oxide (MOX) and non-dispersive infrared sensors was developed to measure concentrations of CH4 and CO2. Laboratory, bench and field testing results demonstrate the capability of UAV to capture, analyze and geo-locate a gas sample during flight operations. The field testing integrated ground sensor nodes and the UAV to measure CO2 concentration at ground and low aerial altitudes, simultaneously. Data collected during the mission was transmitted in real time to a central node for analysis and 3D mapping of the target gas. The results highlights the accomplishment of the first flight mission of a solar powered UAV equipped with a CO2 sensing system integrated with a WSN. The system provides an effective 3D monitoring and can be used in a wide range of environmental applications such as agriculture, bushfires, mining studies, zoology and botanical studies using a ubiquitous low cost technology. PMID:25679312

  6. Sub-arctic Wetland Greenhouse Gases (CO2, CH4 & N2O) Emissions are Driven by Interactions of Environmental Controls and Herbivore Grazers

    NASA Astrophysics Data System (ADS)

    Kelsey, K.; Leffler, A. J.; Beard, K. H.; Choi, R. T.; Welker, J. M.

    2015-12-01

    Climate change is increasing temperatures, altering precipitation regimes and causing earlier growing seasons, particularly at northern latitudes. Such changes in local environmental conditions have the potential to affect biogeochemical cycling including the exchange of greenhouses gases between the atmosphere and the terrestrial biosphere. In addition to the effects of these environmental controls, animals such as migratory geese also influence biogeochemical cycles through grazing, trampling and delivering nutrient-rich fecal matter. In this work we aimed to quantify how local environmental conditions and the presence of grazing interact as drivers of emissions of three key greenhouse gases, CO2, CH4 and N2O, in coastal wetlands of the Yukon Kuskokwim Delta. We explored the magnitude of emissions across gradients of soil temperature and water table depth, and across vegetation types related to the presence of grazing, ranging from no vegetation through grazed and ungrazed vegetation. We also investigated emissions from grazed areas using experimental manipulations of the timing of grazing and advancement of the growing season. We found that local environmental conditions and use by grazers exert interacting controls on emissions of CO2, CH4 and N2O. Emissions of CO2 and CH4 were positively related to soil temperature and CH4 emissions were inversely related to water table depth, but the relationship varied by vegetation type. Net emissions of CO2 were greatest in ungrazed vegetation types (6.62 umols CO2 m-2 sec-1; p=0.0007) whereas CH4 emissions were greatest in the grazed vegetation (122.56 nmols CH4 m-2 sec-1; p=0.037). Flux of N2O was less than 1 nmol N2O m-2 sec-1 across all landscape positions under typical grazing and temperature conditions, but emissions were stimulated to over 10 nmols m-2 sec-1 when grazing occurred early relative to a typical season. Our results indicate that environmental conditions and the presence of migratory herbivores are both

  7. [Temporal variation of soil greenhouse gases fluxes in a cold-temperate Larix gmelinii forest in Inner Mongolia, China].

    PubMed

    Ma, Xiu-Zhi; Zhang, Qiu-Liang; Li, Chang-Sheng; Chen, Gao-Wa; Wang, Fei

    2012-08-01

    By using static chamber-gas chromatograph technique, an in situ measurement was conducted on the soil CH4, CO2, and N2O fluxes in a cold-temperate Larix gmelinii forest in Inner Mongolia from June to September 2007, aimed to understand the diurnal and seasonal variations of soil greenhouse gasses fluxes and their relations with the associated environmental factors in L. gmelinii forests in cold-temperate zone. In growth season, the soil in the L. gmelinii forest was the sink of atmospheric CH4, with the flux ranged from 22.3 to 107.8 microg CH4-C x m(-2) x h(-1). The mean monthly uptake of CH4 in June, July, August, and September was 34.0 +/- 7.1, 71.4 +/- 9.4, 86.3 +/- 7.9, and 40.7 +/- 6.2 microg x m(-2) x h(-1), respectively. The mean diurnal flux of soil CH4 from June to September showed the same variation trend, i. e., peaked at 10:00 am. The diurnal variation of soil CO2 flux showed an obvious double-peak, and the mean monthly CO2 flux was in the order of July > August > June > September. Soil N2O flux varied dramatically from -9.1 to 31.7 microg x m(-2) x h(-1). Soil temperature and humidity were the main factors affecting the CH4 and CO2 fluxes, and soil temperature mainly affected the N2O flux. In the L. gmelinii forest, the CH4, CO2, and N2O fluxes measured at 10:00 am could represent the diurnal CH4, CO2, and N2O fluxes on the same day. PMID:23189692

  8. Comparison of life cycle greenhouse gases from natural gas pathways for medium and heavy-duty vehicles.

    PubMed

    Tong, Fan; Jaramillo, Paulina; Azevedo, Inês M L

    2015-06-16

    The low-cost and abundant supply of shale gas in the United States has increased the interest in using natural gas for transportation. We compare the life cycle greenhouse gas (GHG) emissions from different natural gas pathways for medium and heavy-duty vehicles (MHDVs). For Class 8 tractor-trailers and refuse trucks, none of the natural gas pathways provide emissions reductions per unit of freight-distance moved compared to diesel trucks. When compared to the petroleum-based fuels currently used in these vehicles, CNG and centrally produced LNG increase emissions by 0-3% and 2-13%, respectively, for Class 8 trucks. Battery electric vehicles (BEVs) powered with natural gas-produced electricity are the only fuel-technology combination that achieves emission reductions for Class 8 transit buses (31% reduction compared to the petroleum-fueled vehicles). For non-Class 8 trucks (pick-up trucks, parcel delivery trucks, and box trucks), BEVs reduce emissions significantly (31-40%) compared to their diesel or gasoline counterparts. CNG and propane achieve relatively smaller emissions reductions (0-6% and 19%, respectively, compared to the petroleum-based fuels), while other natural gas pathways increase emissions for non-Class 8 MHDVs. While using natural gas to fuel electric vehicles could achieve large emission reductions for medium-duty trucks, the results suggest there are no great opportunities to achieve large emission reductions for Class 8 trucks through natural gas pathways with current technologies. There are strategies to reduce the carbon footprint of using natural gas for MHDVs, ranging from increasing vehicle fuel efficiency, reducing life cycle methane leakage rate, to achieving the same payloads and cargo volumes as conventional diesel trucks. PMID:25938939

  9. Radiative Forcing by Well-Mixed Greenhouse Gases: Estimates from Climate Models in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4)

    NASA Technical Reports Server (NTRS)

    Collins, W. D.; Ramaswamy, V.; Schwarzkopf, M. D.; Sun, Y.; Portmann, R. W.; Fu, Q.; Casanova, S. E. B.; Dufresne, J.-L.; Fillmore, D. W.; Forster, P. M. D.; Galin, V. Y.; Gohar, L. K.; Ingram, W. J.; Kratz, D. P.; Lefebvre, M.-P.; Li, J.; Marquet, P.; Oinas, V.; Tsushima, Y.; Uchiyama, T.; Zhong, W. Y.

    2006-01-01

    The radiative effects from increased concentrations of well-mixed greenhouse gases (WMGHGs) represent the most significant and best understood anthropogenic forcing of the climate system. The most comprehensive tools for simulating past and future climates influenced by WMGHGs are fully coupled atmosphere-ocean general circulation models (AOGCMs). Because of the importance of WMGHGs as forcing agents it is essential that AOGCMs compute the radiative forcing by these gases as accurately as possible. We present the results of a radiative transfer model intercomparison between the forcings computed by the radiative parameterizations of AOGCMs and by benchmark line-by-line (LBL) codes. The comparison is focused on forcing by CO2, CH4, N2O, CFC-11, CFC-12, and the increased H2O expected in warmer climates. The models included in the intercomparison include several LBL codes and most of the global models submitted to the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4). In general, the LBL models are in excellent agreement with each other. However, in many cases, there are substantial discrepancies among the AOGCMs and between the AOGCMs and LBL codes. In some cases this is because the AOGCMs neglect particular absorbers, in particular the near-infrared effects of CH4 and N2O, while in others it is due to the methods for modeling the radiative processes. The biases in the AOGCM forcings are generally largest at the surface level. We quantify these differences and discuss the implications for interpreting variations in forcing and response across the multimodel ensemble of AOGCM simulations assembled for the IPCC AR4.

  10. Radiative forcing by well-mixed greenhouse gases: Estimates from climate models in the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4)

    NASA Astrophysics Data System (ADS)

    Collins, W. D.; Ramaswamy, V.; Schwarzkopf, M. D.; Sun, Y.; Portmann, R. W.; Fu, Q.; Casanova, S. E. B.; Dufresne, J.-L.; Fillmore, D. W.; Forster, P. M. D.; Galin, V. Y.; Gohar, L. K.; Ingram, W. J.; Kratz, D. P.; Lefebvre, M.-P.; Li, J.; Marquet, P.; Oinas, V.; Tsushima, Y.; Uchiyama, T.; Zhong, W. Y.

    2006-07-01

    The radiative effects from increased concentrations of well-mixed greenhouse gases (WMGHGs) represent the most significant and best understood anthropogenic forcing of the climate system. The most comprehensive tools for simulating past and future climates influenced by WMGHGs are fully coupled atmosphere-ocean general circulation models (AOGCMs). Because of the importance of WMGHGs as forcing agents it is essential that AOGCMs compute the radiative forcing by these gases as accurately as possible. We present the results of a radiative transfer model intercomparison between the forcings computed by the radiative parameterizations of AOGCMs and by benchmark line-by-line (LBL) codes. The comparison is focused on forcing by CO2, CH4, N2O, CFC-11, CFC-12, and the increased H2O expected in warmer climates. The models included in the intercomparison include several LBL codes and most of the global models submitted to the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report (AR4). In general, the LBL models are in excellent agreement with each other. However, in many cases, there are substantial discrepancies among the AOGCMs and between the AOGCMs and LBL codes. In some cases this is because the AOGCMs neglect particular absorbers, in particular the near-infrared effects of CH4 and N2O, while in others it is due to the methods for modeling the radiative processes. The biases in the AOGCM forcings are generally largest at the surface level. We quantify these differences and discuss the implications for interpreting variations in forcing and response across the multimodel ensemble of AOGCM simulations assembled for the IPCC AR4.

  11. High-sensitivity remote detection of atmospheric pollutants and greenhouse gases at low ppm levels using near-infrared tunable diode lasers

    NASA Astrophysics Data System (ADS)

    Roy, Anirban; Upadhyay, Abhishek; Chakraborty, Arup Lal

    2016-05-01

    The concentration of atmospheric pollutants and greenhouse gases needs to be precisely monitored for sustainable industrial development and to predict the climate shifts caused by global warming. Such measurements are made on a continuous basis in ecologically sensitive and urban areas in the advanced countries. Tunable diode laser spectroscopy (TDLS) is the most versatile non-destructive technology currently available for remote measurements of multiple gases with very high selectivity (low cross-sensitivity), very high sensitivity (on the order of ppm and ppb) and under hazardous conditions. We demonstrate absolute measurements of acetylene, methane and carbon dioxide using a fielddeployable fully automated TDLS system that uses calibration-free 2f wavelength modulation spectroscopy (2f WMS) techniques with sensitivities of low ppm levels. A 40 mW, 1531.52 nm distributed feedback (DFB) diode laser, a 10 mW, 1650 nm DFB laser and a 1 mW, 2004 nm vertical cavity surface emitting laser (VCSEL) are used in the experiments to probe the P9 transition of acetylene, R4 transition of methane and R16 transition of carbon dioxide respectively. Data acquisition and on-board analysis comprises a Raspberry Pi-based embedded system that is controllable over a wireless connection. Gas concentration and pressure are simultaneously extracted by fitting the experimental signals to 2f WMS signals simulated using spectroscopic parameters obtained from the HITRAN database. The lowest detected concentration is 11 ppm for acetylene, 275 ppm for methane and 285 ppm for carbon dioxide using a 28 cm long single-pass gas cell.

  12. Update on the Development of Optical Remote Sensing Tools for Quantification of Greenhouse Gases from Distributed Area Sources

    NASA Astrophysics Data System (ADS)

    Douglass, K.; Maxwell, S. E.; Samarov, D. V.; Bienfang, J. C.; Restelli, A.; Liu, X.; Plusquellic, D. F.

    2014-12-01

    Our goal is to develop and validate advanced optical measurement technologies to enable accurate quantification of greenhouse gas (GHG) sources and sinks with a well-characterized uncertainty. Our focus is the measurement of distributed-area sources with spatial scales ranging from of 1 km2 to 10 km2. A few examples of distributed sources include landfills, mines, gas and oil production sites, carbon sequestration sites, enhanced oil-recovery sites, etc. The goal is to measure both concentration and wind speed of the emitted gas to determine the emission flux. To achieve our measurement goals we are developing several complementary differential absorption LIDAR (DIAL) systems. The systems are designed for the detection of methane and carbon dioxide, but they vary in the type of laser source, the range resolution, the wavelength tuning method, detector type, and expected use. A limiting component of DIAL systems in the short wave infrared is detector technology. There are four detectors currently being tested, three single-photon detectors, and one linear-mode, which include an 8 % quantum-efficiency photomultiplier tube, 300 pixel array of Geiger-mode APDs with an effective area of 200 μm, a 100 MHz linear mode APD with a diameter of 500 μm, and a single-pixel Geiger-mode APD gated at 1.25 GHz whose active-area diameter is < 50 μm. We have also acquired a commercially produced mobile aerosol LIDAR system that has the following measurement capabilities: aerosol to molecular scattering ratio, molecular temperature, density, and line-of-sight wind velocity. The aerosol LIDAR system operates at three wavelengths 1064 nm, 532 nm, and 355 nm. Extinction, backscatter, and depolarization measurements are performed at 532 nm and 1064 nm. The wind velocity and temperature measurements are performed at 355 nm and use direct detection methods. The system is housed in a trailer with scanning capabilities. The presentation will provide an overview of the NIST LIDAR systems

  13. The full budget of greenhouse gases in the terrestrial biosphere: From global C project to global GHG project

    NASA Astrophysics Data System (ADS)

    Tian, H.; Lu, C.; Ciais, P.; Michalak, A. M.; Canadell, J.; Saikawa, E.; Huntzinger, D. N.; Gurney, K. R.; Sitch, S.; Zhang, B.; Yang, J.; Bousquet, P.; Bruhwiler, L.; Chen, G.; Dlugokencky, E. J.; Friedlingstein, P.; Melillo, J. M.; Pan, S.; Poulter, B.; Prinn, R. G.; Saunois, M.; Schwalm, C.; Wofsy, S. C.

    2015-12-01

    Terrestrial uptake of carbon dioxide (CO2) partially mitigates global climate change induced by anthropogenic greenhouse (GHG) emissions. However, warming from increasing biogenic emissions of methane (CH4) and nitrous oxide (N2O) resulting from human activities may negate the cooling effect of CO2 uptake by the terrestrial biosphere. Terrestrial fluxes of individual GHGs have been studied intensively, but the net balance of the three major GHGs (CO2, CH4 and N2O) remains uncertain. Here we use bottom-up (BU: e.g., inventory, statistical extrapolation of local flux measurements, process-based modeling) and top-down (TD: atmospheric inversions) approaches to quantify net terrestrial biogenic fluxes of CO2, CH4 and N2O from natural ecosystems, croplands, and other biogenic sectors. After subtracting modeled estimates of pre-industrial fluxes from contemporary biogenic fluxes, we find the biogenic CH4 and N2O emissions resulting from human activities are opposite in sign but 1.6 times in magnitude equivalent to the global land uptake of CO2 in the 2000s based on global warming potential on 100-year time horizon. Among the emissions of CH4 and N2O, those from agriculture are the most important human perturbation, offsetting 1.2 to 1.4 times the global land CO2 sink. Our results suggest that the role of the terrestrial biosphere in exacerbating climate change could be alleviated if net human-induced biogenic GHG emissions were reduced through the implementation of land-based mitigation strategies, with the largest mitigation potential being in Southern Asia, a region that includes both China and India. This study highlights the importance of simultaneously considering three major GHGs in global and regional climate assessments, mitigation options and climate policy decisions, given the likely countervailing impacts of mitigation efforts, such as enhanced N2O emissions with soil C sequestration, paddy-drying to reduce CH4 emissions, and indirect emissions from biofuels.

  14. Dissolved greenhouse gases (nitrous oxide and methane) associated with the natural iron-fertilized Kerguelen region (KEOPS 2 cruise) in the Southern Ocean

    NASA Astrophysics Data System (ADS)

    Farías, L.; Florez-Leiva, L.; Besoain, V.; Fernández, C.

    2014-08-01

    The concentrations of greenhouse gases (GHGs) like nitrous oxide (N2O) and methane (CH4) were measured in the Kerguelen Plateau Region (KPR), an area with annual microalgal bloom caused by natural Fe fertilization, which may stimulate microbes involved in GHG cycling. This study was carried out during the KEOPS 2 cruise during the austral spring of 2011. Two transects were sampled along and across the KRP, the north-south (N-S) transect (46-51° S, 72° E meridian) and the west-east (W-E) transect (66-75° E, 48.3° S latitude), both associated with the presence of a plateau, polar fronts and other mesoscale features. The W-E transect had N2O levels ranging from equilibrium (105%) to light supersaturation (120%) with respect to the atmosphere. CH4 levels fluctuated dramatically, with intense supersaturations (120-970%) in areas close to the coastal waters of Kerguelen Island and in the polar front (PF). There, Fe and nutrient fertilization seem to promote high total chlorophyll a (TChl a) levels. The distribution of both gases was more homogenous in the N-S transect, but CH4 peaked at southeastern stations of the KPR (A3 stations), where phytoplankton bloom was observed. Both gases responded significantly to the patchy distribution of particulate matter as Chl a, stimulated by Fe supply by complex mesoscale circulation. While CH4 appears to be produced mainly at the pycnoclines, N2O seems to be consumed superficially. Air-sea fluxes for N2O (from -10.5 to 8.65, mean 1.71 μmol m-2d-1), and for CH4 (from 0.32 to 38.1, mean 10.07 μmol m-2d-1) reflected sink and source behavior for N2O and source behavior for CH4, with considerable variability associated with a highly fluctuating wind regime and, in the case of CH4, due to its high superficial levels that had not been reported before in the Southern Ocean and may be caused by an intense microbial CH4 cycling.

  15. Dissolved greenhouse gases (nitrous oxide and methane) associated with the naturally iron-fertilized Kerguelen region (KEOPS 2 cruise) in the Southern Ocean

    NASA Astrophysics Data System (ADS)

    Farías, L.; Florez-Leiva, L.; Besoain, V.; Sarthou, G.; Fernández, C.

    2015-03-01

    The concentrations of greenhouse gases (GHGs), such as nitrous oxide (N2O) and methane (CH4), were measured in the Kerguelen Plateau region (KPR). The KPR is affected by an annual microalgal bloom caused by natural iron fertilization, and this may stimulate the microbes involved in GHG cycling. This study was carried out during the KEOPS 2 cruise during the austral spring of 2011. Oceanographic variables, including N2O and CH4, were sampled (from the surface to 500 m depth) in two transects along and across the KRP, the north-south (TNS) transect (46°-51° S, ~ 72° E) and the east-west (TEW) transect (66°-75° E, ~ 48.3° S), both associated with the presence of a plateau, polar front (PF) and other mesoscale features. The TEW presented N2O levels ranging from equilibrium (105%) to slightly supersaturated (120%) with respect to the atmosphere, whereas CH4 levels fluctuated dramatically, being highly supersaturated (120-970%) in areas close to the coastal waters of the Kerguelen Islands and in the PF. The TNS showed a more homogenous distribution for both gases, with N2O and CH4 levels ranging from 88 to 171% and 45 to 666% saturation, respectively. Surface CH4 peaked at southeastern stations of the KPR (A3 stations), where a phytoplankton bloom was observed. Both gases responded significantly, but in contrasting ways (CH4 accumulation and N2O depletion), to the patchy distribution of chlorophyll a. This seems to be associated to the supply of iron from various sources. Air-sea fluxes for N2O (from -10.5 to 8.65, mean 1.25 ± 4.04 μmol m-2 d-1) and for CH4 (from 0.32 to 38.1, mean 10.01 ± 9.97 μmol-2 d-1) indicated that the KPR is both a sink and a source for N2O, as well as a considerable and variable source of CH4. This appears to be associated with biological factors, as well as the transport of water masses enriched with Fe and CH4 from the coastal area of the Kerguelen Islands. These previously unreported results for the Southern Ocean suggest an intense

  16. Chemolithoautotrophic production mediating the cycling of the greenhouse gases N2O and CH4 in an upwelling ecosystem

    NASA Astrophysics Data System (ADS)

    Farías, L.; Fernández, C.; Faúndez, J.; Cornejo, M.; Alcaman, M. E.

    2009-12-01

    The high availability of electron donors occurring in coastal upwelling ecosystems with marked oxyclines favours chemoautotrophy, in turn leading to high N2O and CH4 cycling associated with aerobic NH4+ (AAO) and CH4 oxidation (AMO). This is the case of the highly productive coastal upwelling area off central Chile (36° S), where we evaluated the importance of total chemolithoautotrophic vs. photoautotrophic production, the specific contributions of AAO and AMO to chemosynthesis and their role in gas cycling. Chemolithoautotrophy was studied at a time-series station during monthly (2007-2009) and seasonal cruises (January 2008, September 2008, January 2009) and was assessed in terms of the natural C isotopic ratio of particulate organic carbon (δ13POC), total and specific (associated with AAO and AMO) dark carbon assimilation (CA), and N2O and CH4 cycling experiments. At the oxycline, δ13POC averaged -22.2‰; this was significantly lighter compared to the surface (-19.7‰) and bottom layers (-20.7‰). Total integrated dark CA in the whole water column fluctuated between 19.4 and 2.924 mg C m-2 d-1, was higher during active upwelling, and contributed 0.7 to 49.7% of the total integrated autotrophic CA (photo plus chemoautotrophy), which ranged from 135 to 7.626 mg C m-2 d-1, and averaged 20.3% for the whole sampling period. Dark CA was reduced by 27 to 48% after adding a specific AAO inhibitor (ATU) and by 24 to 76% with GC7, a specific archaea inhibitor. This indicates that AAO and AMO microbes (most of them archaea) were performing dark CA through the oxidation of NH4+ and CH4. Net N2O cycling rates varied between 8.88 and 43 nM d-1, whereas net CH4 cycling rates ranged from -0.41 to -26.8 nM d-1. The addition of both ATU and GC7 reduced N2O accumulation and increased CH4 consumption, suggesting that AAO and AMO were responsible, in part, for the cycling of these gases. These findings show that chemically driven chemolithoautotrophy (with NH4+ and CH4 acting

  17. Idaho National Laboratory FY12 Greenhouse Gas Report

    SciTech Connect

    Kimberly Frerichs

    2013-03-01

    A greenhouse gas (GHG) inventory is a systematic approach to account for the production and release of certain gases generated by an institution from various emission sources. The gases of interest are those that climate science has identified as related to anthropogenic global climate change. This document presents an inventory of GHGs generated during Fiscal Year (FY) 2012 by Idaho National Laboratory (INL), a Department of Energy (DOE) sponsored entity, located in southeastern Idaho.

  18. Idaho National Laboratory's FY11 Greenhouse Gas Report

    SciTech Connect

    Kimberly Frerichs

    2012-03-01

    A greenhouse gas (GHG) inventory is a systematic approach to account for the production and release of certain gases generated by an institution from various emission sources. The gases of interest are those that climate science has identified as related to anthropogenic global climate change. This document presents an inventory of GHGs generated during Fiscal Year (FY) 2011 by Idaho National Laboratory (INL), a Department of Energy (DOE)-sponsored entity, located in southeastern Idaho.

  19. Remote Sensing Observations of Greenhouse Gases from space based and airborne platforms: from SCIAMACHY and MaMap to CarbonSat

    NASA Astrophysics Data System (ADS)

    Burrows, John P.; Schneising, Oliver; Buchwitz, Michael; Bovensmann, Heinrich; Heymann, Jens; Gerilowski, Konstantin; Krings, Thomas; Krautwurst, Sven; Dickerson, Russ

    2015-04-01

    Methane, CH4, e and carbon dioxide, CO2, play an important role in the earth carbon cycle. They are the two most important long lived greenhouse gases produced by anthropogenic fossil fuel combustion. In order to assess accurately the surface fluxes of CH4 or CO2. The Scanning Imaging Absorption Spectrometer for Atmospheric ChartographY, SCIAMACHY, was a national contribution to the ESA Envisat platform: the latter being launched on the 28th February 2002 and operating successfully until April 2012. The SCIAMACHY measurements of the up-welling radiation have been used to retrieve the dry mole fraction of XCH4 and XCO2, providing a unique 10 year record at the spatial resolution of 60 kmx30 km. This data has been used to observe the changing CH4 abundance in the atmosphere and identify anthropogenic such as Fracking and natural sources such as wetlands. The Methane and carbon dioxide Mapper, MaMap, was developed as an aircraft demonstration instrument for our CarbonSat and CarbonSat Constellation concepts. CarbonSat is in Phase A B1 studies as one of two candidate missions for ESA's Earth Explorer 8 Mission. Selected results from SCIAMACHY and Mamap will be presented with a focus on methane and the perspective for CarbonSat.

  20. Relative roles of anthropogenic aerosols and greenhouse gases in land and oceanic monsoon changes during past 156 years in CMIP5 models

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Li, Tim

    2016-05-01

    Relative roles of anthropogenic aerosols (AAs) and greenhouse gases (GHGs) in land and oceanic monsoon changes during boreal summer over the period 1850-2005 in Coupled Model Intercomparison Project Phase 5 (CMIP5) models are explored. It is found that the GHG effect dominates rainfall trend over oceanic monsoon region. As a result, precipitation over western North Pacific (WNP) monsoon region and Intertropical Convergence Zone (ITCZ) over tropical eastern Pacific are strengthened through the so-called "richest-get-richer" mechanism. Over land monsoon region, GHG and AA effects are different over India and East Asia (EA). The two effects tend to offset each other over India, but the AA effect dominates over EA and induces a drying trend. The weakened effect of GHGs on EA is attributed to the large offset of thermodynamic and dynamic effects associated with GHGs. While the former tends to strengthen EA rainfall through increased moisture, the latter tends to decrease EA rainfall due to the strengthened WNP monsoon impact.

  1. Emissions of Greenhouse Gases and Fine Particles (PM2.5) from Wildland Fires in the United States from 2003 to 2011

    NASA Astrophysics Data System (ADS)

    Huang, S.; Larkin, N. K.; Raffuse, S. M.

    2013-12-01

    Wildland fires not only affect adjacent communities, but also produce smoke that can travel long distances and significantly impact downwind communities, alter weather patterns, and contribute to global climate change. As air quality standards have tightened, smoke from wildland fires has faced greater scrutiny from the air quality management community. Wildland fire emissions in the United States from 2003 to 2011 were estimated using the SmartFire2 system and the BlueSky Smoke Modeling Framework. Based on various sources of observational fire activity data, including ground-based incident reports and satellite-derived fire perimeters, fire information was reconciled and passed through a chain of models that estimate fuel loading, fuel consumption, and smoke emissions. While the spatial and temporal distributions of prescribed fires follow a stable pattern, wildfires are difficult to predict and their effects vary greatly from fire to fire. We analyzed the area burned and the emissions of select greenhouse gases (carbon dioxide and methane) and fine particles (PM2.5) from the model outputs to characterize long-term temporal and spatial variations. We will present these results, discuss factors that cause variability and uncertainty, and make comparisons to typical global modeling methods.

  2. Investigation of a new approach to decompose two potent greenhouse gases: photoreduction of SF(6) and SF(5)CF(3) in the presence of acetone.

    PubMed

    Huang, Li; Dong, Wenbo; Zhang, Renxi; Hou, Huiqi

    2007-01-01

    In this paper, we addressed the utilization of photochemical method as an innovative technology for the destruction and removal of two potent greenhouse gases, SF(6) and SF(5)CF(3). The destruction and removal efficiency (DRE) of the process was determined as a function of excitation wavelength, irradiation time, initial ratio of acetone to SF(5)X (X represented F or CF(3)), initial SF(5)X concentration, additive oxygen and water vapor concentration. A complete removal was achieved by a radiation period of 55min and 120min for SF(6)-CH(3)COCH(3) system and SF(5)CF(3)-CH(3)COCH(3) system respectively under 184.9nm irradiation. Extra addition of water vapor can enhance DRE by approximately 6% points in both systems. Further studies with GC/MS and FT-IR proved that no hazardous products such as S(2)F(10), SO(2)F(2), SOF(2), SOF(4) were generated in this process. PMID:16860846

  3. A novel method to decompose two potent greenhouse gases: photoreduction of SF6 and SF5CF3 in the presence of propene.

    PubMed

    Huang, Li; Shen, Yan; Dong, Wenbo; Zhang, Renxi; Zhang, Jianliang; Hou, Huiqi

    2008-03-01

    SF5CF3 and SF6 are the most effective greenhouse gases on a per molecule basis in the atmosphere. Original laboratory trial for photoreduction of them by use of propene as a reactant was performed to develop a novel technique to destroy them. The highly reductive radicals produced during the photolysis of propene at 184.9 nm, such as .CH3, .C2H3, and .C3H5, could efficiently decompose SF6 and SF5CF3 to CH4, elemental sulfur and trace amounts of fluorinated organic compounds. It was further demonstrated that the destruction and removal efficiency (DRE) of SF5X (X represented F or CF3) was highly dependent on the initial propene-to-SF5X ratio. The addition of certain amounts of oxygen and water vapor not only enhanced the DRE but avoided the generation of deposits. In both systems, employment nitrogen as dilution gas lessened the DRE slightly. Given the advantage of less toxic products, the technique might contribute to SF5X remediation. PMID:17640803

  4. Analysis of potential for reducing emissions of greenhouse gases in municipal solid waste in Brazil, in the state and city of Rio de Janeiro

    SciTech Connect

    Loureiro, S.M.; Rovere, E.L.L.; Mahler, C.F.

    2013-05-15

    Highlights: ► We constructed future scenarios of emissions of greenhouse gases in waste. ► Was used the IPCC methodology for calculating emission inventories. ► We calculated the costs of abatement for emissions reduction in landfill waste. ► The results were compared to Brazil, state and city of Rio de Janeiro. ► The higher the environmental passive, the greater the possibility of use of biogas. - Abstract: This paper examines potential changes in solid waste policies for the reduction in GHG for the country of Brazil and one of its major states and cities, Rio de Janeiro, from 2005 to 2030. To examine these policy options, trends in solid waste quantities and associated GHG emissions are derived. Three alternative policy scenarios are evaluated in terms of effectiveness, technology, and economics and conclusions posited regarding optimal strategies for Brazil to implement. These scenarios are been building on the guidelines for national inventories of GHG emissions (IPCC, 2006) and adapted to Brazilian states and municipalities’ boundaries. Based on the results, it is possible to say that the potential revenue from products of solid waste management is more than sufficient to transform the current scenario in this country into one of financial and environmental gains, where the negative impacts of climate change have created a huge opportunity to expand infrastructure for waste management.

  5. Atmospheric station Křešín u Pacova, Czech Republic - a Central European research infrastructure for studying greenhouse gases, aerosols and air quality

    NASA Astrophysics Data System (ADS)

    Dvorská, A.; Sedlák, P.; Schwarz, J.; Fusek, M.; Hanuš, V.; Vodička, P.; Trusina, J.

    2015-05-01

    Long-lasting research infrastructures covering the research areas of atmospheric chemistry, meteorology and climatology are of highest importance. The Atmospheric Station (AS) Křešín u Pacova, central Czech Republic, is focused on monitoring of the occurence and long-range transport of greenhouse gases, atmospheric aerosols, selected gaseous atmospheric pollutants and basic meteorological characteristics. The AS and its 250 m tall tower was built according to the recommendations of the Integrated Carbon Observation System (ICOS) and cooperates with numerous national and international projects and monitoring programmes. First measurements conducted at ground started in 2012, vertical profile measurements were added in 2013. A seasonal variability with slightly higher autumn and winter concentrations of elemental and organic carbon was revealed. The suitability of the doubly left-censored Weibull distribution for modelling and interpretation of elemental carbon concentrations, which are often lower than instrumental quantification limits, was verified. Initial data analysis also suggests that in summer, the tower top at 250 m is frequently above the nocturnal surface inversions, thus being decoupled from local influences.

  6. Substrate lability and plant activity controls greenhouse gas release from Neotropical peatland

    NASA Astrophysics Data System (ADS)

    Sjogersten, Sofie; Hoyos, Jorge; Lomax, Barry; Turner, Ben; Wright, Emma

    2014-05-01

    Almost one third of global CO2 emissions resulting from land use change and substantial CH4 emissions originate from tropical peatlands. However, our understanding of the controls of CO2 and CH4 release from tropical peatlands are limited. The aim of this study was to investigate the role of peat lability and the activity of the vegetation on gas release using a combination of field and laboratory experiments. We demonstrated that peat lability constrained CH4 production to the surface peat under anaerobic conditions. The presence of plants shifted the C balance from a C source to a C sink with respect to CO2 while the activity of the root system strongly influenced CH4 emissions through its impact on soil O2 inputs. Both field and laboratory data suggest a coupling between the photosynthetic activity of the vegetation and the release of both CO2 and CH4 following the circadian rhythm of the dominant plant functional types. Forest clearance for agriculture resulted in elevated CH4 release, which we attribute in part to the cessation of root O2 inputs to the peat. We conclude that high emissions of CO2 and CH4 from forested tropical peatlands are likely driven by labile C inputs from the vegetation but that root O2 release may limit CH4 emissions.

  7. Dispersion modeling of accidental releases of toxic gases - Comparison of the models and their utility for the fire brigades.

    NASA Astrophysics Data System (ADS)

    Stenzel, S.; Baumann-Stanzer, K.

    2009-04-01

    Dispersion modeling of accidental releases of toxic gases - Comparison of the models and their utility for the fire brigades. Sirma Stenzel, Kathrin Baumann-Stanzer In the case of accidental release of hazardous gases in the atmosphere, the emergency responders need a reliable and fast tool to assess the possible consequences and apply the optimal countermeasures. For hazard prediction and simulation of the hazard zones a number of air dispersion models are available. The most model packages (commercial or free of charge) include a chemical database, an intuitive graphical user interface (GUI) and automated graphical output for display the results, they are easy to use and can operate fast and effective during stress situations. The models are designed especially for analyzing different accidental toxic release scenarios ("worst-case scenarios"), preparing emergency response plans and optimal countermeasures as well as for real-time risk assessment and management. There are also possibilities for model direct coupling to automatic meteorological stations, in order to avoid uncertainties in the model output due to insufficient or incorrect meteorological data. Another key problem in coping with accidental toxic release is the relative width spectrum of regulations and values, like IDLH, ERPG, AEGL, MAK etc. and the different criteria for their application. Since the particulate emergency responders and organizations require for their purposes unequal regulations and values, it is quite difficult to predict the individual hazard areas. There are a quite number of research studies and investigations coping with the problem, anyway the end decision is up to the authorities. The research project RETOMOD (reference scenarios calculations for toxic gas releases - model systems and their utility for the fire brigade) was conducted by the Central Institute for Meteorology and Geodynamics (ZAMG) in cooperation with the Vienna fire brigade, OMV Refining & Marketing GmbH and

  8. Controlled Release Fertilizers: An Environmentally Sound and Efficient Method for Greenhouse Crop Fertilization

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Lake Erie is the most polluted of all the Great Lakes. In fact, the Maumee River Watershed alone contributes most of Lake Erie’s phosphorus and sediment load but only 3% of its water, due to the large concentration of agriculture in this portion of the state. The use of controlled release fertilize...

  9. Methane release from the terrestrial ecosystems of greenhouse climates: Challenges and potential (Invited)

    NASA Astrophysics Data System (ADS)

    Pancost, R. D.; Collinson, M.; Evershed, R. P.; Bingham, E.; Talbot, H.; Weijers, J.; Wilde, V.; Riegel, W.

    2009-12-01

    Recent circulation and geochemical modelling suggests that atmospheric methane could have been an important driver of global temperatures during past greenhouse climates. Such conclusions are largely based on our understanding of modern wetland biogeochemistry, including the impact of hydrology, temperature and primary photosynthetic production on rates of methanogenesis. However, validation of these parameters, and of course direct validation of past wetland methane fluxes or atmospheric methane concentrations, are either challenging or currently not possible. Here, we discuss prospects for using lipid biomarkers (and complementary approaches) in lignites to interrogate methane cycling and the environmental conditions that drive it. Potential new proxies include the MBT/CBT index from which mean air temperatures can be reconstructed, allowing direct validation that temperate and polar wetlands experienced greater temperatures during greenhouse times. Second, compound-specific dD values, when coupled to reconstructed vegetation and charcoal records, can provide expanded insight into past wetland hydrology. And finally, the concentrations, distributions and carbon isotopic compositions of archaeal ether lipids and bacterial hopanoids provide direct evidence for increased methanogen or methanotroph biomasss, respectively. This final proxy is based directly on our ongoing investigations of a half dozen Holocene and modern peat deposits; in these, archaeol concentrations range from 0 to 30 ug per g of peat, and putative methanotroph hopanoids represent less than 3% if the total bacteriohopanoids. We illustrate the potential for such an integrated approach using the SE England Cobham lignite deposited during the Palaeocene Eocene Thermal Maximum (PETM). During the PETM, an increase in precipitation and/or runoff and a cessation of fires (collectively revealed by lithologic and vegetation change) apparently drove a dramatic increase in methane production as revealed by a

  10. Global warming potentials; Part 7 of 7 supporting documents. Sector-specific issues and reporting methodologies supporting the general guidelines for voluntary reporting of greenhouse gases under Section 1605(b) of the Energy Policy Act of 1992; Public review draft

    SciTech Connect

    Not Available

    1994-05-31

    This document provides methods to account for the different effects of different gases on the atmosphere. It discusses the rationale and uses for simplified measures to represent human-related effects on climate and provides a brief introduction to a major index, the global warming potential (GWP) index. Appendix 7.A analyzes the science underlying the development of indices for concerns about climate, which is still evolving, evaluates the usefulness of currently available indices, and presents the state of the art for numerical indices and their uncertainties. For concerns about climate, the Intergovernmental Panel on Climate Change (IPCC) has been instrumental in examining relative indices for comparing the radiative influences of greenhouse gases. The IPCC developed the concept of GWPs to provide a simple representation of the relative effects on climate resulting from a unit mass emission of a greenhouse gas. Alternative measures and variations on the definition of GWPs have also been considered and reported.

  11. Effect of Porosity on the Adsorption, Desorption, Trapping and Release of Volatile gases by Amorphous Solid Water

    SciTech Connect

    Ayotte, Patrick; Smith, R. Scott; Stevenson, Kip P.; Dohnalek, Zdenek; Kimmel, Greg A.; Kay, Bruce D.

    2001-12-25

    We compare the adsorption, desorption, trapping, and release of Ar, N2, O2, CO, and CH4, by dense (non-porous) and highly porous amorphous solid water (ASW) films. Molecular beam deposition techniques were used to control the porosity of the vapor deposited ASW thin films. Experiments where the gas species was deposited on top and underneath of dense and porous ASW were conducted. The porous films were found to adsorb between 20 and 50 times more gas than the dense films. The desorption temperature of the adsorbed gas was also dependent on the porosity of the ASW film. The differences between desorption from porous and dense ASW films are attributed to differences in their ability to trap weakly physisorbed gases. The results were largely independent of the gas studied confirming that the adsorption and trapping of gases is dominated by the ASW porosity. These findings show that laboratory studies must account for the growth conditions and their effects on ASW morphology in order accurately predict the properties of astrophysical ices.

  12. Modeling acute health risks associated with accidental releases of toxic gases

    SciTech Connect

    Haskin, F.E.; Ding, C.; Summa, K.J.; Young, M.

    1996-09-01

    CHEM{_}MACCS has been developed from the radiological accident consequence code, MACCS, to perform probabilistic calculations of potential off-site consequences of the accidental atmospheric release of hazardous chemicals. The principal phenomena considered in CHEM{_}MACCS are atmospheric transport, mitigative actions based on dose projection, dose accumulation by a number of pathways, and early and latent health effects. CHEM{_}MACCS provides the following capabilities: (1) statistical weather sampling data (8,760 hourly data points per year), (2) population dose and health effect risk calculations based on site-specific population data, (3) health effects calculations including the consideration of potential site specific mitigative actions (evacuation and shielding), and (4) modeling of multiple release segments. Three different sample problems are contained in this report to show how to use CHEM{_}MACCS. Three test problems are run to compare CHEM{_}MACCS and D2PC. The doses versus the downwind centerline distances from the source for the given doses are in very close agreement.

  13. Modeling of global biogenic emissions for key indirect greenhouse gases and their response to atmospheric CO2 increases and changes in land cover and climate

    NASA Astrophysics Data System (ADS)

    Tao, Zhining; Jain, Atul K.

    2005-11-01

    Natural emissions of nonmethane volatile organic compounds (NMVOCs) play a crucial role in the oxidation capacity of the lower atmosphere and changes in concentrations of major greenhouse gases (GHGs), particularly methane and tropospheric ozone. In this study, we integrate a global biogenic model within a terrestrial ecosystem model to investigate the vegetation and soil emissions of key indirect GHGs, e.g., isoprene, monoterpene, other NMVOCs (OVOC), CO, and NOx. The combination of a high-resolution terrestrial ecosystem model with satellite data allows investigation of the potential changes in net primary productivity (NPP) and resultant biogenic emissions of indirect GHGs due to atmospheric CO2 increases and changes in climate and land use practices. Estimated global total annual vegetation emissions for isoprene, monoterpene, OVOC, and CO are 601, 103, 102, and 73 Tg C, respectively. Estimated NOx emissions from soils are 7.51 Tg N. The land cover changes for croplands generally lead to a decline of vegetation emissions for isoprene OVOC, whereas temperature and atmospheric CO2 increases lead to higher vegetation emissions. The modeled global mean isoprene emissions show relatively large seasonal variations over the previous 20 years from 1981 to 2000 (as much as 31% from year to year). Savanna and boreal forests show large seasonal variations, whereas tropical forests with high plant productivity throughout the year show small seasonal variations. Results of biogenic emissions from 1981 to 2000 indicate that the CO2 fertilization effect, along with changes in climate and land use, causes the overall up-trend in isoprene and OVOC emissions over the past 2 decades. This relationship suggests that future emission scenario estimations for NMVOCs should account for effects of CO2 and climate in order to more accurately estimate local, regional, and global chemical composition of the atmosphere, the global carbon budget, and radiation balance of the Earth

  14. The OceanFlux Greenhouse Gases methodology for deriving a sea surface climatology of CO2 fugacity in support of air-sea gas flux studies

    NASA Astrophysics Data System (ADS)

    Goddijn-Murphy, L. M.; Woolf, D. K.; Land, P. E.; Shutler, J. D.; Donlon, C.

    2015-07-01

    Climatologies, or long-term averages, of essential climate variables are useful for evaluating models and providing a baseline for studying anomalies. The Surface Ocean CO2 Atlas (SOCAT) has made millions of global underway sea surface measurements of CO2 publicly available, all in a uniform format and presented as fugacity, fCO2. As fCO2 is highly sensitive to temperature, the measurements are only valid for the instantaneous sea surface temperature (SST) that is measured concurrently with the in-water CO2 measurement. To create a climatology of fCO2 data suitable for calculating air-sea CO2 fluxes, it is therefore desirable to calculate fCO2 valid for a more consistent and averaged SST. This paper presents the OceanFlux Greenhouse Gases methodology for creating such a climatology. We recomputed SOCAT's fCO2 values for their respective measurement month and year using monthly composite SST data on a 1° × 1° grid from satellite Earth observation and then extrapolated the resulting fCO2 values to reference year 2010. The data were then spatially interpolated onto a 1° × 1° grid of the global oceans to produce 12 monthly fCO2 distributions for 2010, including the prediction errors of fCO2 produced by the spatial interpolation technique. The partial pressure of CO2 (pCO2) is also provided for those who prefer to use pCO2. The CO2 concentration difference between ocean and atmosphere is the thermodynamic driving force of the air-sea CO2 flux, and hence the presented fCO2 distributions can be used in air-sea gas flux calculations together with climatologies of other climate variables.

  15. Carbon and nitrogen compounds and emission of greenhouse gases in ancient and modern soils of the Arkaim Reserve in the Steppe Trans-Ural Region

    NASA Astrophysics Data System (ADS)

    Inubushi, K.; Prikhodko, V. E.; Nagano, Kh.; Manakhov, D. V.

    2015-12-01

    Carbon and nitrogen compounds and the emission of CO2, CH4, and N2O were studied in the ancient buried and modern background soils developed from different parent materials in the Arkaim Reserve of Chelyabinsk oblast. The studies were performed after an 18-year-long period of absence of anthropogenic loads on the local ecosystems. Element contents in the humus horizons of the chernozems of the former plowland and pastures and of the forest soil reach 28-45.6 g/kg for Corg, 2.5-4.5 g/kg for Ntot, 140-423 mg/kg for labile carbon (Cl), 32-73 mg/kg for labile nitrogen (Nl), 350-952 mg/kg for carbon of microbial biomass (Cmic), and 38-85 mg/kg for nitrogen of microbial biomass (Nmic). The contents of different forms of C and N depend on the soil type and texture and on the type of land use, including that before reservation of the territory. The emission of greenhouse gases was examined in this area for the first time. The production of CO2 by the soil buried about 4000 years ago is an order of magnitude lower than that by the modern soil. The emission and sink of N2O are small in both modern and ancient soils. The behavior of methane is clearly different in the automorphic and hydromorphic soils: the former serve as methane sinks, whereas the latter act as methane sources. The rate of the CO2 emission from the soils is controlled by many factors, including the soil type, texture, degree of hydromorphism, composition of parent materials, and type of land use.

  16. Program plan for evaluation and remediation of the generation and release of flammable gases in Hanford Site waste tanks

    SciTech Connect

    Johnson, G.D.

    1991-08-01

    This program plan describes the activities being conducted for the resolution of the flammable gas problem that is associated with 23 high-level waste tanks at the Hanford Site. The classification of the wastes in all of these tanks is not final and some wastes may not be high-level wastes. However, until the characterization and classification is complete, all the tanks are treated as if they contain high-level waste. Of the 23 tanks, Tank 241-SY-101 (referred to as Tank 101-SY) has exhibited significant episodic releases of flammable gases (hydrogen and nitrous oxide) for the past 10 years. The major near-term focus of this program is for the understanding and stabilization of this tank. An understanding of the mechanism for gas generation and the processes for the episodic release will be obtained through sampling of the tank contents, laboratory studies, and modeling of the tank behavior. Additional information will be obtained through new and upgraded instrumentation for the tank. A number of remediation, or stabilization, concepts will be evaluated for near-term (2 to 3 years) applications to Tank 101-SY. Detailed safety assessments are required for all activities that will occur in the tank (sampling, removal of equipment, and addition of new instruments). This program plan presents a discussion of each task, provides schedules for near-term activities, and gives a summary of the expected work for fiscal years 1991, 1992, and 1993. 16 refs., 7 figs., 8 tabs.

  17. Greenhouse gases in the stratosphere

    SciTech Connect

    Wenyi Zhong; Haigh, J.D. ); Pyle, J.A. )

    1993-02-20

    The potential radiative forcing in the stratosphere of changing concentrations of ozone, methane, nitrous oxide and chlorofluorocarbons 11 and 12 is assessed. Significant changes in heating rate in the lower stratosphere are found. The response of a fully interactive radiative-photochemical-dynamical two-dimensional model to such changes in gaseous concentrations is investigated. The inclusion of CH[sub 4], N[sub 2]O and the CFC in the radiation scheme causes a small (1 K) decrease in temperature throughout the stratosphere after 50 model years with a resulting increase in ozone column up to 1% in summer high latitudes. An experiment in which lower stratospheric ozone concentrations were forcibly reduced in line with recent satellite observations results in significant (several degrees) temperature decrease in this region. Such decreases may be very significant in maintaining polar ozone loss. 20 refs., 12 figs., 2 tabs.

  18. The Release of Trapped Gases from Amorphous Solid Water Films: II. “Bottom-Up” Induced Desorption Pathways

    SciTech Connect

    May, Robert A.; Smith, R. Scott; Kay, Bruce D.

    2013-03-14

    In this (Paper II) and the preceding companion paper (Paper I) we investigate the mechanisms for the release of trapped gases from underneath of amorphous solid water (ASW) films. In Paper I, we focused on the low coverage (pressure) regime where the release mechanism is controlled by crystallization-induced cracks formed in the ASW overlayer. In that regime the results were largely independent of the particular gas underlayer. Here in Paper II, we focus on the high coverage (pressure) regime where new desorption pathways become accessible prior to ASW crystallization. In contrast to the results for the low coverage regime (Paper I), the release mechanism is a function of the multilayer thickness and composition, displaying dramatically different behavior between Ar, Kr, Xe, CH4, N2, O2, and CO. Two primary desorption pathways are observed. The first occurs between 100 and 150 K and manifests itself as sharp, extremely narrow desorption peaks. Temperature programmed desorption is utilized to show that abrupt desorption bursts are due to pressure induced structural failure of the ASW overlyaer. The second pathway occurs at low temperature (typically <100 K) where broad desorption peaks are observed. Desorption through this pathway is attributed to diffusion through pores and connected pathways formed during ASW deposition. The extent of desorption and the lineshape of the low temperature desorption peak are dependent on the substrate on which the gas underlayer is deposited. Angle dependent ballistic deposition of the ASW is used vary the porosity of overlayer and confirm that the low temperature desorption pathway is due to porosity that is inherent in the ASW overlayer during deposition.

  19. Profiling of Greenhouse Gases from Space by Infrared-Laser Occultation and Demonstration by a 144 km Crosslink Experiment at the Canary Islands

    NASA Astrophysics Data System (ADS)

    Kirchengast, G.; Schweitzer, S.; Proschek, V.; Bernath, P.; Thomas, B.; Wang, J.; Brooke, J.; Tereszchuk, K.; Gonzalez Abad, G.; Hargreaves, R.; Beale, C. A.; Martin, P.; Kasiutsich, V.; Gerbig, C.; Kolle, O.; Loescher, A.

    2011-12-01

    Low Earth Orbit (LEO) transmitter and receiver satellites provide the basis for LEO-LEO microwave and infrared-laser occultation (LMIO), a new active limb sounding method for climate benchmark profiling of greenhouse gases (GHGs), thermodynamic variables and wind in the free atmosphere (Kirchengast and Schweitzer, GRL, 38, L13701, 2011). The LEO-LEO infrared-laser occultation (LIO) part of LMIO can provide accurate profiles of all main GHGs, including CO2, CH4, N2O, H2O, O3, and isotopes 13CO2 and 18OCO, by exploiting differential absorption between carefully selected absorption ("on-line") and reference ("off-line") laser signals targeting suitable GHG absorption lines within 2 to 2.5 μm. This spectral range resides in the "hole" between the shortwave-solar and longwave-terrestrial Planck spectra so that natural background radiation is minimal to negligible. We present the fundamentals and discuss the estimated performance of LMIO-based GHG profiling, including from quasi-realistic end-to-end performance simulations considering also aerosols and clouds. We found monthly-mean GHG profiles, assuming 30 to 40 native profiles averaged per climatological "grid cell" per month, accurate to <0.15 to 0.5% r.m.s. error over the upper troposphere and lower stratosphere at ~1 km vertical resolution (e.g., CO2 <1 ppm, CH4 <7 ppb; residual biases estimated less than half these r.m.s. values). Encouraged by the potential of LMIO for GHG profiling in the free atmosphere indicated by these results we undertook in July 2011 a first ground-based demonstration experiment of LIO sounding along a ~144 km link at ~2.4 km altitude between observatories at the islands of La Palma and Tenerife being part of the Canary Islands (ESA-funded experiment project by Bernath et al.; Univ. York, Univ. Graz, Univ. Manchester, MPI Jena). With transmitter and receiver breadboard equipment built for four infrared-laser signals we aimed in this campaign at CO2, CH4, and H2O measurements under field

  20. SAFT-γ force field for the simulation of molecular fluids: 2. Coarse-grained models of greenhouse gases, refrigerants, and long alkanes.

    PubMed

    Avendaño, Carlos; Lafitte, Thomas; Adjiman, Claire S; Galindo, Amparo; Müller, Erich A; Jackson, George

    2013-03-01

    In the first paper of this series [C. Avendaño, T. Lafitte, A. Galindo, C. S. Adjiman, G. Jackson, and E. A. Müller, J. Phys. Chem. B2011, 115, 11154] we introduced the SAFT-γ force field for molecular simulation of fluids. In our approach, a molecular-based equation of state (EoS) is used to obtain coarse-grained (CG) intermolecular potentials that can then be employed in molecular simulation over a wide range of thermodynamic conditions of the fluid. The macroscopic experimental data for the vapor-liquid equilibria (saturated liquid density and vapor pressure) of a given system are represented with the SAFT-VR Mie EoS and used to estimate effective intermolecular parameters that provide a good description of the thermodynamic properties by exploring a wide parameter space for models based on the Mie (generalized Lennard-Jones) potential. This methodology was first used to develop a simple single-segment CG Mie model of carbon dioxide (CO2) which allows for a reliable representation of the fluid-phase equilibria (for which the model was parametrized), as well as an accurate prediction of other properties such as the enthalpy of vaporization, interfacial tension, supercritical density, and second-derivative thermodynamic properties (thermal expansivity, isothermal compressibility, heat capacity, Joule-Thomson coefficient, and speed of sound). In our current paper, the methodology is further applied and extended to develop effective SAFT-γ CG Mie force fields for some important greenhouse gases including carbon tetrafluoride (CF4) and sulfur hexafluoride (SF6), modeled as simple spherical molecules, and for long linear alkanes including n-decane (n-C10H22) and n-eicosane (n-C20H42), modeled as homonuclear chains of spherical Mie segments. We also apply the SAFT-γ methodology to obtain a CG homonuclear two-segment Mie intermolecular potential for the more challenging polar and asymmetric compound 2,3,3,3-tetrafluoro-1-propene (HFO-1234yf), a novel replacement

  1. Emissions of air pollutants and greenhouse gases over Asian regions during 2000-2008: Regional Emission inventory in ASia (REAS) version 2

    NASA Astrophysics Data System (ADS)

    Kurokawa, J.; Ohara, T.; Morikawa, T.; Hanayama, S.; Greet, J.-M.; Fukui, T.; Kawashima, K.; Akimoto, H.

    2013-04-01

    We have updated the Regional Emission inventory in ASia (REAS) as version 2.1. REAS 2.1 includes most major air pollutants and greenhouse gases from each year during 2000 and 2008 and following areas of Asia: East, Southeast, South, and Central Asia and the Asian part of Russia. Emissions are estimated for each country and region using updated activity data and parameters. Monthly gridded data with a 0.25 × 0.25° resolution are also provided. Asian emissions for each species in 2008 are as follows (with their growth rate from 2000 to 2008): 56.9 Tg (+34%) for SO2, 53.9 Tg (+54%) for NOx, 359.5 Tg (+34%) for CO, 68.5 Tg (+46%) for non-methane volatile organic compounds, 32.8 Tg (+17%) for NH3, 36.4 Tg (+45%) for PM10, 24.7 Tg (+42%) for PM2.5, 3.03 Tg (+35%) for black carbon, 7.72 Tg (+21%) for organic carbon, 182.2 Tg (+32%) for CH4, 5.80 Tg (+18%) for N2O, and 16.7 Pg (+59%) for CO2. By country, China and India were respectively the largest and second largest contributors to Asian emissions. Both countries also had higher growth rates in emissions than others because of their continuous increases in energy consumption, industrial activities, and infrastructure development. In China, emission mitigation measures have been implemented gradually. Emissions of SO2 in China increased from 2000 to 2006 and then began to decrease as flue-gas desulfurization was installed to large power plants. On the other hand, emissions of air pollutants in total East Asia except for China decreased from 2000 to 2008 owing to lower economic growth rates and more effective emission regulations in Japan, South Korea, and Taiwan. Emissions from other regions generally increased from 2000 to 2008, although their relative shares of total Asian emissions are smaller than those of China and India. Tables of annual emissions by country and region broken down by sub-sector and fuel type, and monthly gridded emission data with a resolution of 0.25 × 0.25° for the major sectors are available

  2. Emissions of air pollutants and greenhouse gases over Asian regions during 2000-2008: Regional Emission inventory in ASia (REAS) version 2

    NASA Astrophysics Data System (ADS)

    Kurokawa, J.; Ohara, T.; Morikawa, T.; Hanayama, S.; Janssens-Maenhout, G.; Fukui, T.; Kawashima, K.; Akimoto, H.

    2013-11-01

    We have updated the Regional Emission inventory in ASia (REAS) as version 2.1. REAS 2.1 includes most major air pollutants and greenhouse gases from each year during 2000 and 2008 and following areas of Asia: East, Southeast, South, and Central Asia and the Asian part of Russia. Emissions are estimated for each country and region using updated activity data and parameters. Monthly gridded data with a 0.25° × 0.25° resolution are also provided. Asian emissions for each species in 2008 are as follows (with their growth rate from 2000 to 2008): 56.9 Tg (+34%) for SO2, 53.9 Tg (+54%) for NOx, 359.5 Tg (+34%) for CO, 68.5 Tg (+46%) for non-methane volatile organic compounds, 32.8 Tg (+17%) for NH3, 36.4 Tg (+45%) for PM10, 24.7 Tg (+42%) for PM2.5, 3.03 Tg (+35%) for black carbon, 7.72 Tg (+21%) for organic carbon, 182.2 Tg (+32%) for CH4, 5.80 Tg (+18%) for N2O, and 16.0 Pg (+57%) for CO2. By country, China and India were respectively the largest and second largest contributors to Asian emissions. Both countries also had higher growth rates in emissions than others because of their continuous increases in energy consumption, industrial activities, and infrastructure development. In China, emission mitigation measures have been implemented gradually. Emissions of SO2 in China increased from 2000 to 2006 and then began to decrease as flue-gas desulphurization was installed to large power plants. On the other hand, emissions of air pollutants in total East Asia except for China decreased from 2000 to 2008 owing to lower economic growth rates and more effective emission regulations in Japan, South Korea, and Taiwan. Emissions from other regions generally increased from 2000 to 2008, although their relative shares of total Asian emissions are smaller than those of China and India. Tables of annual emissions by country and region broken down by sub-sector and fuel type, and monthly gridded emission data with a resolution of 0.25° × 0.25° for the major sectors are

  3. Biases in greenhouse gases static chambers measurements in stabilization ponds: Comparison of flux estimation using linear and non-linear models

    NASA Astrophysics Data System (ADS)

    Silva, Juan P.; Lasso, Ana; Lubberding, Henk J.; Peña, Miguel R.; Gijzen, Hubert J.

    2015-05-01

    The closed static chamber technique is widely used to quantify greenhouse gases (GHG) i.e. CH4, CO2 and N2O from aquatic and wastewater treatment systems. However, chamber-measured fluxes over air-water interfaces appear to be subject to considerable uncertainty, depending on the chamber design, lack of air mixing in the chamber, concentration gradient changes during the deployment, and irregular eruptions of gas accumulated in the sediment. In this study, the closed static chamber technique was tested in an anaerobic pond operating under tropical conditions. The closed static chambers were found to be reliable to measure GHG, but an intrinsic limitation of using closed static chambers is that not all the data for gas concentrations measured within a chamber headspace can be used to estimate the flux due to gradient concentration curves with non-plausible and physical explanations. Based on the total data set, the percentage of curves accepted was 93.6, 87.2, and 73% for CH4, CO2 and N2O, respectively. The statistical analyses demonstrated that only considering linear regression was inappropriate (i.e. approximately 40% of the data for CH4, CO2 and N2O were best fitted to a non-linear regression) for the determination of GHG flux from stabilization ponds by the closed static chamber technique. In this work, it is clear that when R2adj-non-lin > R2adj-lin, the application of linear regression models is not recommended, as it leads to an underestimation of GHG fluxes by 10-50%. This suggests that adopting only or mostly linear regression models will affect the GHG inventories obtained by using closed static chambers. According to our results, the misuse of the usual R2 parameter and only the linear regression model to estimate the fluxes will lead to reporting erroneous information on the real contribution of GHG emissions from wastewater. Therefore, the R2adj and non-linear regression model analysis should be used to reduce the biases in flux estimation by the

  4. [Short-term effects of fire disturbance on greenhouse gases emission from Betula platyphylla-forested wetland in Xiaoxing'an Mountains, Northeast China].

    PubMed

    Mu, Chang-cheng; Zhang, Bo-wen; Han, Li-dong; Yu, Li-li; Gu, Han

    2011-04-01

    could decrease the greenhouse gases emission from Betula platyphylla-forested wetland, and planned firing could be properly implemented in wetland management. PMID:21774304

  5. Greenhouse gas fluxes and NO release from a Chinese subtropical rice-winter wheat rotation system under nitrogen fertilizer management

    NASA Astrophysics Data System (ADS)

    Yao, Zhisheng; Zheng, Xunhua; Wang, Rui; Dong, Haibo; Xie, Baohua; Mei, Baoling; Zhou, Zaixing; Zhu, Jianguo

    2013-06-01

    synthetic nitrogen fertilizers play an important role in increasing cereal grain yields, there have been increased concerns about their intensive utilization and environmental consequences. The overall goal of this study is to gain an insight into the integrated evaluation of greenhouse gas emission and nitric oxide (NO) release and grain yield as affected by nitrogen fertilization in a subtropical rice-wheat rotation system. The assessment was based on four consecutive yearly measurements of the fluxes of methane (CH4), nitrous oxide (N2O) and ecosystem respiration (CO2), and the simultaneous observation of NO emissions in nonrice seasons under three fertilization practices (i.e., the conventional farmers' practice with common nitrogen application rate, an alternative practice with reduced nitrogen input, and no nitrogen application as a control). Clearly, these trace gas fluxes showed largely intra-annual and interannual variations, highlighting the importance of entire year measurement for multiple years to achieve representative annual estimates. The annual mean CH4 fluxes varied from 95 kg C ha-1 (7.8 kg C t-1 grain) for the farmers' practice to 205 kg C ha-1 (25.7 kg C t-1 grain) for the control, indicating that nitrogen fertilization inhibited CH4 emissions. Across all the years, the annual N2O emissions increased exponentially with an increasing nitrogen rate and harvested aboveground biomass. The annual N2O emission averaged 1.3-5.3 kg N ha-1(159-444 g N t-1 grain) for all treatments. The annual direct emission factors of N2O-N tended to increase with increasing nitrogen rate and averaged 0.61% and 0.85% for the alternative and farmers' practices, respectively. Over all nonrice seasons, the seasonal mean NO emissions ranged from 0.15 to 1.4 kg N ha-1(58-253 g N t-1 grain), and were equivalent to 0.43% to 0.54% of the applied nitrogen. Averaging across the 4 years, the annual aggregate emissions of CH4 and N2O were 7.4 t CO2-eq ha-1(928 kg CO2-eq t-1grain

  6. Greenhouse gas mitigation options for Washington State

    SciTech Connect

    Garcia, N.

    1996-04-01

    President Clinton, in 1993, established a goal for the United States to return emissions of greenhouse gases to 1990 levels by the year 2000. One effort established to help meet this goal was a three part Environmental Protection Agency state grant program. Washington State completed part one of this program with the release of the 1990 greenhouse gas emissions inventory and 2010 projected inventory. This document completes part two by detailing alternative greenhouse gas mitigation options. In part three of the program EPA, working in partnership with the States, may help fund innovative greenhouse gas reduction strategies. The greenhouse gas control options analyzed in this report have a wide range of greenhouse gas reductions, costs, and implementation requirements. In order to select and implement a prudent mix of control strategies, policy makers need to have some notion of the potential change in climate, the consequences of that change and the uncertainties contained therein. By understanding the risks of climate change, policy makers can better balance the use of scarce public resources for concerns that are immediate and present against those that affect future generations. Therefore, prior to analyzing alternative greenhouse gas control measures, this report briefly describes the phenomenon and uncertainties of global climate change, and then projects the likely consequences for Washington state.

  7. Simultaneous quantification of methane and carbon dioxide fluxes reveals that a shallow arctic methane seep is a net sink for greenhouse gases

    NASA Astrophysics Data System (ADS)

    Pohlman, J.; Greinert, J.; Ruppel, C. D.; Silyakova, A.; Vielstädte, L.; Magen, C.; Casso, M.; Bunz, S.; Mienert, J.

    2015-12-01

    Warming of high-latitude continental-margin oceans has the potential to release large quantities of carbon from gas hydrate and other sedimentary reservoirs. To assess how carbon mobilized from the seafloor might amplify global warming or alter ocean chemistry, a robust analysis of the concentrations and isotopic content of methane and carbon dioxide (CO2) in the water column and atmosphere is required. To this effect, a gas analysis system consisting of three cavity ring-down spectrometers was developed to obtain a real-time, three-dimensional characterization of the distribution and isotopic variability of methane and CO2 at a shallow (<100 m water depth) bubbling methane seep offshore of western Svalbard. Surface water methane concentrations from the continuous-flow CRDS system agreed remarkably well with discrete samples analyzed by the GC-based headspace analysis technique and with a CRDS-based discrete sample analysis module. Reliable carbon isotope data were also obtained from the CRDSs once an isotopic calibration routine was applied. The resulting data revealed that CO2 uptake from the atmosphere within the surface water methane plume overlying the gas seep was elevated by 36-45% relative to surrounding waters. In comparison to the positive radiative forcing effect expected from the methane emissions, the negative radiative forcing potential from CO2 uptake was 32-43 times greater. Lower water temperatures, elevated chlorophyll-fluorescence and 13C-enriched CO2 within the surface methane plume suggest that bubble-driven upwelling of cold, nutrient-rich water stimulated CO2 uptake by phytoplankton. The observation that a shallow methane seep has a net negative radiative forcing effect challenges the widely-held perception that methane seeps contribute to the global atmospheric greenhouse gas burden.

  8. Comparative Climate Responses of Anthropogenic Greenhouse Gases, All Major Aerosol Components, Black Carbon, and Methane, Accounting for the Evolution of the Aerosol Mixing State and of Clouds/Precipitation from Multiple Aerosol Size Distributions

    NASA Astrophysics Data System (ADS)

    Jacobson, M. Z.

    2005-12-01

    Several modeling studies to date have simulated the global climate response of anthropogenic greenhouse gases and bulk (non-size-resolved) sulfate or generic aerosol particles together, but no study has examined the climate response of greenhouse gases simultaneously with all major size- and composition resolved aerosol particle components. Such a study is important for improving our understanding of the effects of anthropogenic pollutants on climate. Here, the GATOR-GCMOM model is used to study the global climate response of (a) all major greenhouse gases and size-resolved aerosol components, (b) all major greenhouse gases alone, (c) fossil-fuel soot (black carbon, primary organic matter, sulfuric acid, bisulfate, sulfate), and (d) methane. Aerosol components treated in all simulations included water, black carbon, primary organic carbon, secondary organic carbon, sulfuric acid, bisulfate, sulfate, nitrate, chloride, ammonium, sodium, hydrogen ion, soil dust, and pollen/spores. Fossil-fuel soot (FFS) was emitted into its own size distribution. All other components, including biofuel and biomass soot, sea-spray, soil dust, etc., were emitted into a second distribution (MIX). The FFS distribution grew by condensation of secondary organic matter and sulfuric acid, hydration of water, and dissolution of nitric acid, ammonia, and hydrochloric acid. It self-coagulated and heterocoagulated with the MIX distribution, which also grew by condensation, hydration, and dissolution. Treatment of separate distributions for FFS allowed FFS to evolve from an external mixture to an internal mixture. In both distributions, black carbon was treated as a core component for optical calculations. Both aerosol distributions served as CCN during explicit size-resolved cloud formation. The resulting clouds grew by coagulation and condensation, coagulated with interstitial aerosol particles, and fell to the surface as rain and snow, carrying aerosol constituents with them. Thus, cloud

  9. The NOAA Annual Greenhouse Gas Index - 2012 Update

    NASA Astrophysics Data System (ADS)

    Butler, J. H.; Montzka, S. A.; Conway, T. J.; Dlugokencky, E. J.; Elkins, J. W.; Masari, K. A.; Schnell, R. C.; Tans, P. P.

    2012-04-01

    For the past several decades, the U.S. National Oceanic and Atmospheric Administration (NOAA) has monitored all of the long-lived atmospheric greenhouse gases. These global measurements have provided input to databases, analyses, and various relevant products, including national and international climate assessments. To make these data more useful and available, NOAA several years ago released its Annual Greenhouse Gas Index (AGGI), http://www.esrl.noaa.gov/gmd/aggi. This index, based on the climate forcing properties of long-lived greenhouse gases, was designed to enhance the connection between scientists and society by providing a normalized standard that can be easily understood and followed. The long-lived gases capture most of the radiative forcing, and uncertainty in their measurement is very small. This allows us to provide a robust measure and assessment of the long-term, radiative influence of these gases. Continuous greenhouse gas measurements are made at baseline climate observatories (Pt. Barrow, Alaska; Mauna Loa, Hawaii; American Samoa; and the South Pole) and weekly flask air samples are collected through a global network of over 60 sites, including an international cooperative program for carbon dioxide and other greenhouse gases. The gas samples are analyzed at NOAA's Earth System Research Laboratory (NOAA/ESRL) in Boulder, Colorado, using WMO standard reference gases prepared by NOAA/ESRL. The AGGI is normalized to 1.00 in 1990, the Kyoto Climate Protocol baseline year. In 2010, the AGGI was 1.29, indicating that global radiative forcing by long-lived greenhouse gases had increased 29% since 1990. During the 1980s CO2 accounted for about 50-60% of the annual increase in radiative forcing by long-lived greenhouse gases, whereas, since 2000, it has accounted for 85-90% of this increase each year. After nearly a decade of virtually level concentrations in the atmosphere, methane (CH4) increased measurably over the past 2-3 years, as did its

  10. Greenhouse gas emissions and reactive nitrogen releases from rice production with simultaneous incorporation of wheat straw and nitrogen fertilizer

    NASA Astrophysics Data System (ADS)

    Xia, Longlong; Xia, Yongqiu; Ma, Shutan; Wang, Jinyang; Wang, Shuwei; Zhou, Wei; Yan, Xiaoyuan

    2016-08-01

    Impacts of simultaneous inputs of crop straw and nitrogen (N) fertilizer on greenhouse gas (GHG) emissions and N losses from rice production are not well understood. A 2-year field experiment was established in a rice-wheat cropping system in the Taihu Lake region (TLR) of China to evaluate the GHG intensity (GHGI) as well as reactive N intensity (NrI) of rice production with inputs of wheat straw and N fertilizer. The field experiment included five treatments of different N fertilization rates for rice production: 0 (RN0), 120 (RN120), 180 (RN180), 240 (RN240), and 300 kg N ha-1 (RN300, traditional N application rate in the TLR). Wheat straws were fully incorporated into soil before rice transplantation. The meta-analytic technique was employed to evaluate various Nr losses. Results showed that the response of rice yield to N rate successfully fitted a quadratic model, while N fertilization promoted Nr discharges exponentially (nitrous oxide emission, N leaching, and runoff) or linearly (ammonia volatilization). The GHGI of rice production ranged from 1.20 (RN240) to 1.61 kg CO2 equivalent (CO2 eq) kg-1 (RN0), while NrI varied from 2.14 (RN0) to 10.92 g N kg-1 (RN300). Methane (CH4) emission dominated the GHGI with a proportion of 70.2-88.6 % due to direct straw incorporation, while ammonia (NH3) volatilization dominated the NrI with proportion of 53.5-57.4 %. Damage costs to environment incurred by GHG and Nr releases from current rice production (RN300) accounted for 8.8 and 4.9 % of farmers' incomes, respectively. Cutting N application rate from 300 (traditional N rate) to 240 kg N ha-1 could improve rice yield and nitrogen use efficiency by 2.14 and 10.30 %, respectively, while simultaneously reducing GHGI by 13 %, NrI by 23 %, and total environmental costs by 16 %. Moreover, the reduction of 60 kg N ha-1 improved farmers' income by CNY 639 ha-1, which would provide them with an incentive to change the current N application rate. Our study suggests that GHG

  11. A qualitative study of the retention and release of volatile gases in JSC-1A lunar soil simulant at room temperature under ultrahigh vacuum (UHV) conditions

    NASA Astrophysics Data System (ADS)

    Patrick, Edward L.; Mandt, K. E.; Escobedo, S. M.; Winters, G. S.; Mitchell, J. N.; Teolis, B. D.

    2015-07-01

    We conducted a qualitative study to simulate the flux of volatile gases expected to occur at the lunar surface due to cometary impact or lunar outgassing events. A small sample cell containing 8.8 g of JSC-1A lunar soil simulant in a vacuum system with a base pressure of 1.5 × 10-8 Torr was exposed to various gases using dynamic pressure dosing at room temperature to observe any retention of those gases as a function of the exposure times, temperatures and pressures used. Gases included pure argon, a five-component gas mixture (H2, He, Ne, N2, Ar), a simulated Mars atmospheric mixture (CO2, N2, Ar, CO, O2), and a simulated Titan mixture (N2, CH4). Results at exposure pressures of approximately 1.5 × 10-8 Torr above background showed no observable retention of rare gases, slight retention of molecular gases, but surface retention of the triatomic gas CO2 occurred at room temperature with a time to reach equilibrium of greater than 10 min, which was an unanticipated result. Despite several bakeouts and months under ultrahigh vacuum (UHV) conditions, trace levels of atmospheric gases continued to evolve from the simulant. Mechanical and optical probing of the simulant surface increased this latent gas evolution, particularly for CO2 and CO, with some evidence also for the release of CH4. We assert our results are, by analogy, applicable to protocols and instrumentation needed for conducting analytical chemistry aboard future landed lunar missions.

  12. "Atmospheric Measurements by Ultra-Light SpEctrometer" (AMULSE) dedicated to vertical profile measurements of greenhouse gases (CO2, CH4) under stratospheric balloons: instrumental development and field application.

    NASA Astrophysics Data System (ADS)

    Maamary, Rabih; Joly, Lilian; Decarpenterie, Thomas; Cousin, Julien; Dumelié, Nicolas; Grouiez, Bruno; Albora, Grégory; Chauvin, Nicolas; Miftah-El-Khair, Zineb; Legain, Dominique; Tzanos, Diane; Barrié, Joel; Moulin, Eric; Ramonet, Michel; Bréon, François-Marie; Durry, Georges

    2016-04-01

    Human activities disrupt natural biogeochemical cycles such as the carbon and contribute to an increase in the concentrations of the greenhouse gases (carbone dioxide and methane) in the atmosphere. The current atmospheric transport modeling (the vertical trade) still represents an important source of uncertainty in the determination of regional flows of greenhouse gases, which means that a good knowledge of the vertical distribution of CO2 is necessary to (1) make the link between the ground measurements and spatial measurements that consider an integrated concentration over the entire column of the atmosphere, (2) validate and if possible improve CO2 transport model to make the link between surface emissions and observed concentration. The aim of this work is to develop a lightweight instrument (based on mid-infrared laser spectrometry principles) for in-situ measuring at high temporal/spatial resolution (5 Hz) the vertical profiles of the CO2 and the CH4 using balloons (meteorological and BSO at high precision levels (< 1 ppm in 1 second integration time for the CO2 sensor, and smaller than several tenths of ppb in 1 second integration time for the CH4 sensor). The instrument should be lighter than 2.5 kg in order to facilitate authorizations, costs and logistics flights. These laser spectrometers are built on recent instrumental developments. Several flights were successfully done in the region Champagne-Ardenne and in Canada recently. Aknowledgments: The authors acknowledge financial supports from CNES, CNRS défi instrumental and the region Champagne-Ardenne.

  13. The Release of Trapped Gases from Amorphous Solid Water Films: I. “Top-Down” Crystallization-Induced Crack Propagation Probed using the Molecular Volcano

    SciTech Connect

    May, Robert A.; Smith, R. Scott; Kay, Bruce D.

    2013-03-14

    In this (Paper I) and the companion paper (Paper II) we investigate the mechanisms for the release of trapped gases from underneath of amorphous solid water (ASW) films. In prior work, we reported the episodic release of trapped gases in concert with the crystallization ASW, a phenomenon that we termed the "molecular volcano". The observed abrupt desorption is due to the formation of cracks that span the film to form a connected pathway for release. In this paper we utilize the "molecular volcano" desorption peak to characterize the formation of crystallization-induced cracks. We find that the crack length and distribution are independent of the trapped gas (Ar, Kr, Xe, CH4, N2, O2 or CO). Selective placement of the inert gas layer is used to show that cracks form near the top of the film and propagate downward into the film. Isothermal experiments reveal that, after some induction time, cracks propagate linearly in time with an Arrhenius dependent velocity corresponding to an activation energy of 54 kJ/mol. This value is consistent with the crystallization growth rate reported by others and establishes a direct connection between crystallization growth rate and the crack propagation rate. A two-step model in which nucleation and crystallization occurs in an induction zone near the top of the film followed by the propagation of a crystallization/crack front into the film is in good agreement with the temperature programmed desorption results.

  14. Composition of solar wind noble gases released by surface oxidation of a metal separate from the Weston meteorite

    NASA Technical Reports Server (NTRS)

    Becker, R. H.; Pepin, R. O.

    1991-01-01

    The paper reports on a set of experiments intended to test the feasibility of determining elemental and isotopic ratios of the noble gases and nitrogen in the solar wind in metal separates from gas-rich ordinary chondrites. Helium, neon, and argon show clear evidence of a solar wind signature, while no solar component could be identified for xenon and nitrogen. Helium, neon, and argon elemental isotopic ratios appear to depend on depth within the metal grains. The ratios derived indicate that the Weston meteorite did not acquire its solar wind gases from a recent exposure to solar wind, but more probably at a time in the past similar to or even earlier than the exposure time of Apollo 17 breccias. The Ar-36/Ar-38 ratio, in tandem with other recent determinations of this value, indicates that the solar and terrestrial values can no longer be assumed to be equivalent.

  15. Policy implications of greenhouse warming

    SciTech Connect

    Not Available

    1991-01-01

    Contents: background; the greenhouse gases and their effects; policy framework; adaptation; mitigation; international considerations; findings and conclusions; recommendations; questions and answers about greenhouse warming; background information on synthesis panel members and professional staff; and membership lists for effects, mitigation, and adaptation panels.

  16. Mesospheric removal of very long-lived greenhouse gases SF6 and CFC-115 by metal reactions, Lyman-α photolysis, and electron attachment.

    PubMed

    Totterdill, Anna; Kovács, Tamás; Gómez Martín, Juan Carlos; Feng, Wuhu; Plane, John M C

    2015-03-12

    The fluorinated gases SF6 and C2F5Cl (CFC-115) are chemically inert with atmospheric lifetimes of many centuries which, combined with their strong absorption of IR radiation, results in unusually high global warming potentials. Very long lifetimes imply that mesospheric sinks could make important contributions to their atmospheric removal. In order to investigate this, the photolysis cross sections at the prominent solar Lyman-α emission line (121.6 nm), and the reaction kinetics of SF6 and CFC-115 with the neutral meteoric metal atoms Na, K, Mg, and Fe over large temperature ranges, were measured experimentally. The Na and K reactions exhibit significant non-Arrhenius behavior; quantum chemistry calculations of the potential energy surfaces for the SF6 reactions indicate that the Na and K reactions with SF6 are probably activated by vibrational excitation of the F-SF5 (v3) stretching mode. A limited set of kinetic measurements on Na + SF5CF3 are also presented. The atmospheric removal of these long-lived gases by a variety of processes is then evaluated. For SF6, the removal processes in decreasing order of importance are electron attachment, VUV photolysis, and reaction with K, Na, and H. For CFC-115, the removal processes in decreasing order of importance are reaction with O((1)D), VUV photolysis, and reaction with Na, K, and H. PMID:25647411

  17. [Summer Greenhouse Gases Exchange Flux Across Water-air Interface in Three Water Reservoirs Located in Different Geologic Setting in Guangxi, China].

    PubMed

    Li, Jian-hong; Pu, Jun-bing; Sun, Ping-an; Yuan, Dao-xian; Liu, Wen; Zhang, Tao; Mo, Xue

    2015-11-01

    Due to special hydrogeochemical characteristics of calcium-rich, alkaline and DIC-rich ( dissolved inorganic carbon) environment controlled by the weathering products from carbonate rock, the exchange characteristics, processes and controlling factors of greenhouse gas (CO2 and CH4) across water-air interface in karst water reservoir show obvious differences from those of non-karst water reservoir. Three water reservoirs (Dalongdong reservoir-karst reservoir, Wulixia reservoir--semi karst reservoir, Si'anjiang reservoir-non-karst reservoir) located in different geologic setting in Guangxi Zhuang Autonomous Region, China were chosen to reveal characteristics and controlling factors of greenhouse gas exchange flux across water-air interface. Two common approaches, floating chamber (FC) and thin boundary layer models (TBL), were employed to research and contrast greenhouse gas exchange flux across water-air interface from three reservoirs. The results showed that: (1) surface-layer water in reservoir area and discharging water under dam in Dalongdong water reservoir were the source of atmospheric CO2 and CH4. Surface-layer water in reservoir area in Wulixia water reservoir was the sink of atmospheric CO2 and the source of atmospheric CH4, while discharging water under dam was the source of atmospheric CO2 and CH4. Surface-layer water in Si'anjiang water reservoir was the sink of atmospheric CO2 and source of atmospheric CH4. (2) CO2 and CH4 effluxes in discharging water under dam were much more than those in surface-layer water in reservoir area regardless of karst reservoir or non karst reservoir. Accordingly, more attention should be paid to the CO2 and CH4 emission from discharging water under dam. (3) In the absence of submerged soil organic matters and plants, the difference of CH4 effluxes between karst groundwater-fed reservoir ( Dalongdong water reservoir) and non-karst area ( Wulixia water reservoir and Si'anjiang water reservoir) was less. However, CO2

  18. Development of inexpensive continuous emission monitors for feedback control of combustion devices that minimize greenhouse gases, toxic emissions, and ozone damaging products

    SciTech Connect

    Funk, D.J.; Moore, D.S.; Mongia, R.K.; Tomita, E.; Hsu, F.K.; Talbot, L.; Dibble, R.W.; Lovett, J.; Yamazaki, Akira

    1998-11-01

    This is the final report of a three-year, Laboratory Directed Research and Development project at the Los Alamos National Laboratory. Combustion is the major cause of poor urban air quality, of depletion of the ozone layer, and a major source of the greenhouse gas, carbon dioxide. Careful control of combustor conditions is important for minimizing the effects of combustion on the environment. The authors have developed sensitive, inexpensive continuous emission monitors that will assist in direct feedback of turbine power systems and provide assurance to the public and the operators of the facilities that their facility emissions lie within the accepted bounds. These include a robust solid-state Fourier transform spectrometer for rapid gas analysis, based on the use of ferroelectric liquid crystal technology, and an infrared helium-neon probe for real time measurement of combustor air-to-fuel ratios.

  19. The Greenhouse Effect and Built Environment Education.

    ERIC Educational Resources Information Center

    Greenall Gough, Annette; Gough, Noel

    The greenhouse effect has always existed. Without the greenhouse effect, Earth could well have the oven-like environment of Venus or the deep-freeze environment of Mars. There is some debate about how much the Earth's surface temperature will rise given a certain amount of increase in the amount of greenhouse gases such as carbon dioxide, nitrous…

  20. NUTRIENT RELEASE FROM CONTROLLLED-RELEASE FERTILIZERS IN ACID SUBSTRATE IN A GREENHOUSE ENVIRONMENT: II.LEACHATE CALCIUM, MAGNESIUM, IRON MANGANESE, ZINC, COPPER, AND MOLYBDENUM CONCENTRATIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leachate from containerized substrate containing one of four different controlled-release fertilizers (Osmocote, Nutricote, Polyon, or Multicote) were monitored for concentrations of Ca, Mg, Fe, Mn, Zn, Cu and Mo during a 47-week period. Environmental and cultural practices simulated an unheated gr...

  1. Leachate Micronutrient Concentrations From Greenhouse-Grown 'Phoenicia' Azaleas When Using Four Different Types of Controlled-Release Fertilizers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Concentrations of iron, manganese, copper, zinc and molybdenum were measured for leachate collected from container substrate containing one of four types of controlled-release fertilizers (Osmocote plus Micromax, Nutricote, Polyon, and Multicote) during a 47-week plant production cycle. The 2.4 L co...

  2. Greenhouse production of Impatiens wallerana using a controlled-release fertiliser produces quality finished plants with enhanced garden performance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutrient management during production can greatly influence post-production quality of plants. The objective of this research was to evaluate the effect of controlled release fertilizer (CRF) applied at the time of plug planting on the garden performance (post-production) of impatiens (Impatiens wal...

  3. Linking thermal skin gradients at the sea-surface to the radiative coupling of the atmosphere and ocean: a mechanism for heating of the oceans by atmospheric greenhouse gases

    NASA Astrophysics Data System (ADS)

    Minnett, P. J.

    2006-05-01

    Over most of the world's oceans the primary mechanism for heat exchange between ocean and atmosphere is radiative. The majority of the insolation incident at the top of atmosphere propagates to the surface without being absorbed by the atmosphere, and most is then absorbed in the uppermost several meters of the ocean leading to solar heating of the oceanic surface layer. However, much of this heat is given back to the atmosphere, locally or after advection, through sensible and latent heat fluxes, and through infrared emission. The heat flux to the atmosphere is achieved though conduction though the skin layer of the ocean, within which a temperature gradient exists, so that the interfacial temperature of the ocean is cooler than the bulk temperature below. The thickness of the conductive skin layer is of comparable size to the emission (and absorption) depth of infrared radiation in water. The differences in the skin SST and the subsurface bulk temperature are typically a few tenths of a degree, an amount that is important in terms of attempting to detect oceanic warming caused by climate change. Given that the ocean absorbs the infrared radiation emitted by the atmosphere, including by greenhouse gases, within the radiative skin layer, concern has been expressed about how the increasing levels of greenhouse gases can heat the ocean. However, the skin temperature gradient is believed to be responsive to the intensity of the incident infrared radiation at the surface, and this modulates the heat flow from ocean to atmosphere. Empirical evidence to support this hypothesis will be presented, based on measurements taken at sea using the Marine-Atmospheric Emitted Radiance Interferometer (M-AERI). This is a well-calibrated shipboard spectroradiometer, a Fourier Transform Interferometer, which is used to make very accurate measurements of the skin SST. By referencing these skin temperatures to those measured at a depth of ~5cm from a nearby surface float, the size of

  4. Spatial variability of greenhouse gases emissions (CO2, CH4, N2O) in a tropical hydroelectric reservoir flooding primary forest (Petit Saut Reservoir, French Guiana)

    NASA Astrophysics Data System (ADS)

    Cailleaud, Emilie; Guérin, Frédéric; Bouillon, Steven; Sarrazin, Max; Serça, Dominique

    2014-05-01

    At the Petit Saut Reservoir (PSR, French Guiana, South America), vertical profiles were performed at 5 stations in the open waters (OW) and 6 stations in two shallow flooded forest (FF) areas between April 2012 and September 2013. Measurements included physico-chemical parameters, ammonium, nitrate and dissolved greenhouse gas (CO2, CH4, N2O) concentrations, dissolved and particulate organic carbon (DOC, POC) and nitrogen (PN), δ13C-POC and δ15N-PN . The diffusive fluxes were calculated from surface concentrations. The aim of this study was to estimate the spatial variations of greenhouse gas emissions at a dentrical hydroelectric reservoir located in the tropics and flooding primary forest. Twenty years after impoundment, the water column of the PSR is permanently and tightly stratified thermally in the FF whereas in the OW, the thermal gradients are not as stable. The different hydrodynamical behaviours between the two different zones have significant consequences on the biogeochemistry: oxygen barely diffuses down to the hypolimnion in the FF whereas destratification occurs sporadically during the rainy season in the OW. Although we found the same range of POC in the FF and the OW (2.5-29 μmol L-1) and 20% more DOC at the bottom of OW than in the FF (229-878 μmol L-1), CO2 and CH4 concentrations were always significantly higher in the FF (CO2: 11-1412 μmol L-1, CH4: 0.001-1015 μmol L-1) than in the OW. On average, the CO2 concentrations were 30-40% higher in the FF than in the OW and the CH4 concentrations were three times higher in the FF than in the OW. The δ13C-POC and C:N values did not suggest substantial differences in the sources of OM between the FF and OW. At all stations, POC at the bottom has an isotopic signature slightly lighter than the terrestrial OM in the surrounding forest whereas the isotopic signature of surface POM would result from phytoplankton and methanotrophs. The vertical profiles of nitrogen compounds reveal that the main

  5. Assessing the impact on chronic disease of incorporating the societal cost of greenhouse gases into the price of food: an econometric and comparative risk assessment modelling study

    PubMed Central

    Briggs, Adam D M; Kehlbacher, Ariane; Tiffin, Richard; Garnett, Tara; Rayner, Mike; Scarborough, Peter

    2013-01-01

    Objectives To model the impact on chronic disease of a tax on UK food and drink that internalises the wider costs to society of greenhouse gas (GHG) emissions and to estimate the potential revenue. Design An econometric and comparative risk assessment modelling study. Setting The UK. Participants The UK adult population. Interventions Two tax scenarios are modelled: (A) a tax of £2.72/tonne carbon dioxide equivalents (tCO2e)/100 g product applied to all food and drink groups with above average GHG emissions. (B) As with scenario (A) but food groups with emissions below average are subsidised to create a tax neutral scenario. Outcome measures Primary outcomes are change in UK population mortality from chronic diseases following the implementation of each taxation strategy, the change in the UK GHG emissions and the predicted revenue. Secondary outcomes are the changes to the micronutrient composition of the UK diet. Results Scenario (A) results in 7770 (95% credible intervals 7150 to 8390) deaths averted and a reduction in GHG emissions of 18 683 (14 665to 22 889) ktCO2e/year. Estimated annual revenue is £2.02 (£1.98 to £2.06) billion. Scenario (B) results in 2685 (1966 to 3402) extra deaths and a reduction in GHG emissions of 15 228 (11 245to 19 492) ktCO2e/year. Conclusions Incorporating the societal cost of GHG into the price of foods could save 7770 lives in the UK each year, reduce food-related GHG emissions and generate substantial tax revenue. The revenue neutral scenario (B) demonstrates that sustainability and health goals are not always aligned. Future work should focus on investigating the health impact by population subgroup and on designing fiscal strategies to promote both sustainable and healthy diets. PMID:24154517

  6. U. S. bites greenhouse bullet and gags

    SciTech Connect

    Kerr, R.A.

    1991-02-22

    Delegates from more than 100 countries gathered in Chantilly, VA for the first meeting of the UN-sponsored Intergovernmental Convention on Climate Change and reached an agreement on their organizational structure for negotiating how to reduce global warming. However, the commitment of the US to reduce the release of CO{sub 2} emission was very disappointing. The US attitude toward CO{sub 2} emission is totally unchanged, and US policy includes no provision other than those already in place to reduce the greenhouse gases. The plan of the administration to take action now to reduce climate changes really includes only the administrations already announced intentions to stabilize the greenhouse gas emissions by the year 2000. The administration is not yet fully convinced that there is substantial scientific evidence supporting greenhouse warming, and there is general concern that the economic costs of moderating the greenhouse effect might be excessive. There is a good measure of free market ideology involved in the US policy of opposition to reduction of CO{sub 2} emissions. In fact, CO{sub 2} emissions in the US are predicted to rise by 15% by the year 2000.

  7. Impacts of an African Green Revolution on Greenhouse Gases and Pollution Precursors: Nonlinear Trace N Gas Emission Responses to Incremental Increases in Fertilizer Inputs in a Western Kenyan Maize Field

    NASA Astrophysics Data System (ADS)

    Hickman, J. E.; Palm, C.

    2011-12-01

    Over the last several decades, agricultural soils in many parts of sub-Saharan Africa have become depleted of nitrogen (N) and other nutrients, creating challenges to achieving food security in many countries. At only 7 kg N ha-1 yr-1, average fertilizer application rates in the region are an order of magnitude lower than typical rates in the United States, and well below optimal levels. Increased use of nutrient inputs is a centerpiece of most African Green Revolution strategies, making it important to quantify the impacts of this change in practices as farmers begin moving towards 50-80 kg N ha-1 yr-1. Increased N inputs are invariably accompanied by losses of trace N gases to the atmosphere, including the greenhouse gas nitrous oxide (N2O), and nitric oxide (NO), a precursor to tropospheric ozone pollution. Several investigations of greenhouse gas emissions and one investigation of NO emissions from sub-Saharan agricultural systems have been conducted over the last 20 years, but they are few in number and were not designed to identify potentially important thresholds in the response of trace gas emissions to fertilization rate. Here we examine the response function of NO and N2O emissions to 6 different levels of inorganic fertilizer additions in a maize field in Yala, Kenya during the 2011 long rainy season. We used a randomized complete block design incorporating inorganic fertilizer treatments of 0, 50, 75, 100, 150, and 200 kg N ha-1 in 4 blocks. After each of 2 fertilizer applications, we measured trace gas fluxes daily, and conducted weekly measurements until trace gas emissions subsided to control levels. We fit the data to linear and exponential models relating N gas emissions to N input levels, and conducted a model comparison using AIC. Preliminary analysis suggests that NO emissions do respond in a non-linear fashion over the course of 67 days, as has been found in several commercial agroecosystems for N2O. Although N2O emissions responded linearly

  8. Dynamics of greenhouse gases (CO2, CH4, N2O) along the Zambezi River and major tributaries, and their importance in the riverine carbon budget

    NASA Astrophysics Data System (ADS)

    Teodoru, C. R.; Nyoni, F. C.; Borges, A. V.; Darchambeau, F.; Nyambe, I.; Bouillon, S.

    2015-04-01

    Spanning over 3000 km in length and with a catchment of approximately 1.4 million km2, the Zambezi River is the fourth largest river in Africa and the largest flowing into the Indian Ocean from the African continent. We present data on greenhouse gas (GHG: carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O)) concentrations and fluxes, as well as data that allow for characterization of sources and dynamics of carbon pools collected along the Zambezi River, reservoirs and several of its tributaries during 2012 and 2013 and over two climatic seasons (dry and wet) to constrain the interannual variability, seasonality and spatial heterogeneity along the aquatic continuum. All GHG concentrations showed high spatial variability (coefficient of variation: 1.01 for CO2, 2.65 for CH4 and 0.21 for N2O). Overall, there was no unidirectional pattern along the river stretch (i.e., decrease or increase towards the ocean), as the spatial heterogeneity of GHGs appeared to be determined mainly by the connectivity with floodplains and wetlands as well as the presence of man-made structures (reservoirs) and natural barriers (waterfalls, rapids). Highest CO2 and CH4 concentrations in the main channel were found downstream of extensive floodplains/wetlands. Undersaturated CO2 conditions, in contrast, were characteristic of the surface waters of the two large reservoirs along the Zambezi mainstem. N2O concentrations showed the opposite pattern, being lowest downstream of the floodplains and highest in reservoirs. Among tributaries, highest concentrations of both CO2 and CH4 were measured in the Shire River, whereas low values were characteristic of more turbid systems such as the Luangwa and Mazoe rivers. The interannual variability in the Zambezi River was relatively large for both CO2 and CH4, and significantly higher concentrations (up to 2-fold) were measured during wet seasons compared to the dry season. Interannual variability of N2O was less pronounced, but higher values

  9. Estimation of greenhouse gases (N2O, CH4 and CO2) from no-till cropland under increased temperature and altered precipitation regime: a DAYCENT model approach

    NASA Astrophysics Data System (ADS)

    Rafique, Rashad; Kumar, Sandeep; Luo, Yiqi; Xu, Xianli; Li, Dejun; Zhang, Wei; Asam, Zaki-ul-Zaman

    2014-07-01

    Greenhouse gas (GHG) emissions play an important role in regulating the Earth surface temperature. GHG emissions from soils are sensitive to climate change and land management practices. According to general circulation model (GCM) predictions, the Earth will experience a combination of increased temperature and altered precipitation regimes which may result in an increase or a decrease of GHG exchange. The effect of climate change on GHG emissions can be examined through both experiments and by applying process-based models, which have become more popular. The performance of those models can be improved significantly by appropriate calibration procedures. The objectives of this study are to: (i) calibrate the DAYCENT model using advance parameter estimation (PEST) software and to (ii) examine simulated GHG dynamics at daily and seasonal time-scales under a climate change scenario of increased temperature (2 °C) and a precipitation regime change where 40% of precipitation during the dry season was redistributed to the wet season. The algorithmic calibration improved the model performance by reducing the sum of weighted squared residual differences by up to 223% (decreased from 1635 to 505 g N2O-N ha- 1 d- 1) for N2O and 22% (decreased from 623 to 507% WFPS) for water filled pore space (WFPS) simulation results. In the altered climate scenario, total N2O and CO2 fluxes decreased by 9% (from 2.31 to 2.10 kg N2O-N ha- 1 yr- 1) and 38% (from 1134.08 to 699.56 kg CO2 ha- 1 yr- 1) respectively, whereas CH4 fluxes increased by 10% (from 1.62 to 1.80 kg CH4 ha- 1 yr- 1). Our results show a larger impact of altered climate on CO2 as compared to N2O and CH4 emissions. The main difference in all GHG emissions was observed in summer period due to drought conditions created by reduced precipitation and increased temperatures. However, the GHG dynamics can also be attributed to no-till practices which play an important role in changing the soil moisture conditions for aerobic

  10. Enteric methane production and greenhouse gases balance of diets differing in concentrate in the fattening phase of a beef production system.

    PubMed

    Doreau, M; van der Werf, H M G; Micol, D; Dubroeucq, H; Agabriel, J; Rochette, Y; Martin, C

    2011-08-01

    The purposes of this study were 1) to assess the effects of 3 high-concentrate diets on enteric CH(4) production, total tract digestibility, and rumen fermentation of beef cattle, and 2) to evaluate, by life cycle assessment, the potential effects of these feeding systems on the environment. Six bulls (age of 12.4 mo and BW of 417 kg at midexperiment) of the Blond d'Aquitaine breed were assigned to 3 dietary treatments in a replicated 3 × 3 Latin square design. Diets consisted of 1) 49% natural grassland hay, 41% ground corn grain, and 10% soybean meal (hay); 2) 63% corn silage, 21% ground corn grain, and 16% soybean meal (CS); and 3) 70% ground corn grain, 16% soybean meal, and 14% wheat straw (CG). Daily CH(4) emission (g/d), measured using the sulfur hexafluoride tracer technique, was similar for the hay and CS diets and was 56% greater than for the CG diet (P < 0.001). This difference between diets was maintained when CH(4) output was expressed by unit of feed intake (P < 0.001) or digested feed (P < 0.001). Gross energy intake loss as CH(4) averaged 6.9% for the hay and CS diets and 3.2% for the CG diet (P < 0.001). Organic matter intake and GE intake did not differ between diets. Organic matter digestibility was less for the hay diet than for the CS and CG diets (P=0.008). Digestibility of NDF was greatest for the hay diet, intermediate for the CS diet, and least for the CG diet (P=0.02), with ADF digestibility being similar between the hay and CS diets and greater than for the CG diet (P < 0.001). The rumen pH at 5 h postfeeding was less for animals fed the CG diet compared with those fed the other 2 diets (on average, 5.1 vs. 5.9, respectively; P < 0.001). Total CH(4) emission (enteric + manure) was least for the CG diet, whereas N(2)O and CO(2) emissions were greatest for the CG diet. Total greenhouse gas emissions were least for the CG diet when C sequestration by grasslands was not taken into account. PMID:21383032

  11. Soil-atmosphere fluxes of the greenhouse gases N2O, CO2 and CH4 from a long term compost experiment in Austria.

    NASA Astrophysics Data System (ADS)

    Spann, Caroline; Spiegel, Heide; Kitzler, Barbara

    2016-04-01

    The application of composts as fertilizers is becoming increasingly important to achieve a closed-loop economy. However, greenhouse gas (GHG) emissions, especially N2O, from agricultural fields may increase as well. In this study different compost types and N amounts were investigated, especially in terms of their GHG fluxes. We used the closed chamber method to estimate GHG flux rates over one vegetation period from an agricultural soil fertilized with different compost types. The study was conducted on a long term compost experiment site near Linz (Austria) with a crop rotation. The soil is a loamy silt and in 2015 maize was planted. Six different compost treatments were investigated. Organic waste compost (OWC) and farmyard manure compost (FMC) was applied with nitrogen concentrations of 175 (OWC1, FYC1) and 525 kg N ha-1 (OWC3, FYC3). Two compost treatments were fertilized additionally with 80 kg N ha.1 mineral fertilizer (OWC2, FYC2). One treatment (TN) was fertilized only with mineral fertilizer (120 kg N ha-1) and one treatment was not fertilized at all (C). Additionally to the GHG flux rates, ammonium and nitrate content, microbial biomass C and N and different enzyme activities were analysed in the top soil. Nitrous oxide (N2O) was emitted over the entire vegetation period with highest fluxes from April until June, until the plants have been established sufficiently. Overall, at the FMC treatments (FYC2, FYC3) highest fluxes were measured. Compared to FMC, lower N2O emissions were measured from the OWC treatments. The combination of compost and mineral N fertilization resulted in the highest N2O emissions, especially after precipitation events. The treatments OWC1 and FYC1 were not different from the control. Methane (CH4) was mainly taken up at all treatments, but uptake rates were lower at the high N input sites (OWC3, FYC3) with no differences between the compost types. No significant differences were found in the soil respiration rates.

  12. Spatiotemporal dynamics of phosphorus release, oxygen consumption and greenhouse gas emissions after localised soil amendment with organic fertilisers.

    PubMed

    Christel, Wibke; Zhu, Kun; Hoefer, Christoph; Kreuzeder, Andreas; Santner, Jakob; Bruun, Sander; Magid, Jakob; Jensen, Lars Stoumann

    2016-06-01

    Organic fertilisation inevitably leads to heterogeneous distribution of organic matter and nutrients in soil, i.e. due to uneven surface spreading or inhomogeneous incorporation. The resulting localised hotspots of nutrient application will induce various biotic and abiotic nutrient turnover processes and fixation in the residue sphere, giving rise to distinct differences in nutrient availability, soil oxygen content and greenhouse gas (GHG) production. In this study we investigated the spatiotemporal dynamics of the reaction of manure solids and manure solids char with soil, focusing on their phosphorus (P) availability, as current emphasis on improving societal P efficiency through recycling waste or bio-based fertilisers necessitates a sound understanding of their behaviour. Soil layers amended at a constant P application rate with either pig manure solids or char made from pig manure solids were incubated for three weeks between layers of non-amended, P-depleted soil. Spatial and temporal changes in and around the amendment layers were simultaneously investigated in this study using a sandwich sensor consisting of a planar oxygen optode and multi-element diffusive gradients in thin films (DGT) gels, combined with GHG emission measurements. After three weeks of incubation, the soil containing a layer amended with manure solids had a lower overall O2 content and had emitted significantly more CO2 than the non-amended control or the char-amended soil. The P availability from manure solids was initially higher than that from the char, but decreased over time, whereas from the char-amended layer P availability increased in the same period. In both treatments, increases in P availability were confined to the amended soil layer and did not greatly affect P availability in the directly adjacent soil layers during the three-week incubation. These results highlight the importance of placing organic P fertilisers close to where the plant roots will grow in order to

  13. The effects of inert gases and other general anaesthetics on the release of acetylcholine from the guinea-pig ileum

    PubMed Central

    Halliday, D.J.X.; Little, Hilary J.; Paton, W.D.M.

    1979-01-01

    1 The actions of a range of general anaesthetic agents on the rates of release of acetylcholine from the guinea-pig ileum were tested, by means of a superfusion system designed to maintain the tissues under physiological conditions in a high pressure chamber. 2 Anaesthetic pressures of nitrous oxide, nitrogen, argon, sulphur hexafluoride and carbon tetrafluoride caused increases in acetylcholine ouput but the concentrations required did not parallel their general anaesthetic potencies. The changes were not altered by the application of a pressure of helium which reverses their general anaesthetic actions in vivo. 3 Urethane (50.5 mM and 101 mM, but not 16.8 mM) decreased acetylcholine release rates and this effect was not reversed by helium pressure. 4 Octanol (1.0 mM, but not 0.124 mM or 0.496 mM) decreased the acetylcholine output. This action was not reversed by helium pressure. The lack of effect on acetylcholine release from tetrodotoxin-treated tissues suggested that the changes were produced by blockade of action potential conduction. 5 Phenobarbitone (0.4 mM but not 0.2 mM) also decreased acetylcholine output. Although the concentrations required were lower than those which have been previously shown to block axonal conduction, no changes were seen in tetrodotoxin-treated tissues. The decreases were less when helium pressure was applied than at atmospheric pressure but full pressure reversal, as occurs in vivo, was not seen. 6 The effects on acetylcholine output exerted by the anaesthetics studied did not reflect their general anaesthetic action in the concentrations required, the direction of the changes produced or in the response to helium pressure. They represent specific actions which are likely to contribute to the individual differences which are seen between the physiological actions of the anaesthetics in vivo. PMID:227512

  14. Direct measurements of chemical composition of shock-induced gases from calcite: an intense global warming after the Chicxulub impact due to the indirect greenhouse effect of carbon monoxide

    NASA Astrophysics Data System (ADS)

    Kawaragi, Ko; Sekine, Yasuhito; Kadono, Toshihiko; Sugita, Seiji; Ohno, Sohsuke; Ishibashi, Ko; Kurosawa, Kosuke; Matsui, Takafumi; Ikeda, Susumu

    2009-05-01

    Shock-induced devolatilization in hypervelocity impacts has been considered to play important roles in the atmospheric evolution and mass extinctions in Earth's history. Although the chemical composition of shock-induced gas species from carbonate rocks has been considered as a key to understand the environmental change after the Chicxulub impact, it has not been investigated extensively before. Here, we conduct direct measurements of the chemical composition (CO/CO 2) of shock-induced gas species from calcite (CaCO 3) using both a laser gun system and an isotopic labeling technique. The CO/CO 2 ratio of the shock-induced gas species from calcite is measured to be 2.02 ± 0.41, suggesting that gaseous CO has been dominant in the shock-induced gases in the Chicxulub impact. In order to evaluate the environmental effects of the injection of CO gas, we investigated the post-impact atmospheric chemistry by incorporating our experimental results into a tropospheric photochemical model. The results suggest that an intense (2-5 °C) global warming would have lasted for several years after a Chicxulub-size impact mainly due to the greenhouse effect of tropospheric O 3, which is produced via photochemical reactions associated with CO gas. Such an intense global warming could have damaged the biosphere in the mass extinction at the Cretaceous-Paleogene (K-P) boundary.

  15. Influence of orography on variability of a non-CO2 greenhouse gases concentrations measured at Kasprowy Wierch station, Tatra, Poland

    NASA Astrophysics Data System (ADS)

    Necki, J.; Chmura, L.; Zimnoch, M.

    2012-04-01

    Kasprowy Wierch is a mountain peak in north-western Tatra mountain ridge, where meteorological station was settled in year 1936. As the station is situated in the convergence area of three large valleys it suffers from breeze wind and from frequent katabatic winds as well. Unfortunately vertical constituent of wind is not measured at the station. Prevailing wind direction pattern in this part of Europe is western circulation. However 75-years record consistently indicate south as the predominant direction of wind at Kasprowy Wierch. Two of the valleys coming toward this mountain peak are forcing the transport of air exactly from that direction. Since 1994 trace gas analysis is performed at the station. In year 1996 automated gas chromatograph was installed at the station and data are collected till nowadays. "In situ" concentrations of CH4, N2O and SF6 are measured every 16 minutes. Since 2010 also H2 and CO are observed at the station. Especially carbon monoxide concentration may be used as a proxy for determination of cases when local emission contaminates the air coming to the station. Usually location of the station in high mountain assures large distance from sources of the observed gases. Some tracers connected with human activity like carbon monoxide or sulphur hexafluoride may indicate proximity of anthropogenic sources of N2O and CH4, which might substantially change the composition of air surrounding the station. Valley breezes occur frequently in each mountain area. It has a large influence on air composition meas-ured at the mountain stations. It can be clearly noticed in CH4 and N2O records and at much smaller rate in SF6 concentration as well. Diurnal cycle of methane and nitrous oxide concentrations reflects substantial change of its value usually shortly after the sunrise. During the summer season a valley breeze transports to the station an air enriched in CH4 and N2O from the peat lands located along the foothill of Tatra mountains. Additionally

  16. An Open-Path Tunable Diode Laser Sensor for Measurement of Greenhouse Gases at the Bonanza Creek Long Term Ecological Research Site near Fairbanks, Alaska

    NASA Astrophysics Data System (ADS)

    Bailey, D. M.; Adkins, E. M.; Miller, J. H. H.

    2015-12-01

    Permafrost makes up one-quarter of the Earth's terrestrial surface and, as global temperatures continue to increase, it is at risk of thawing. Thawing permafrost has the potential to release twice the amount of carbon than is currently in the atmosphere. A multi-year field campaign has begun in collaboration with the University of Alaska - Fairbanks, NASA Goddard Space Flight Center, and our group at George Washington University to study carbon feedbacks during a springtime thaw at the Bonanza Creek Long Term Ecological Research site near Fairbanks, Alaska. Here we present initial results from our near-infrared open-path instrument for the detection of ambient concentrations of carbon dioxide (in subsequent field campaigns a second channel for methane detection will be added). The optics launch-box portion of the instrument couples a near-infrared distributed feedback laser operating near 1605 nm for carbon detection with a visible laser for alignment purposes. The outgoing beam is directed through a 3.2-mm hole in a parabolic mirror and the launch-box is oriented using a two axis, alt-azi telescope mount so that the beam will hit the retroreflector target at a set distance downfield. The beam then retraces the path back to the launch-box where the light is collected on the surface of the parabolic mirror and focused onto a multi-mode fiber for detection. Using a National Instruments data acquisition system we are able to collect 500 scans per second which allows for long-term data averaging and subsequently increases the signal-to-noise ratio of our signal. The entire system has the ability to run on less than 40 W of power. In June 2015, the instrument was deployed to a thermokarst collapse scar bog in the Bonanza Creek Experimental Forest. With a 90 meter total pathlength we were able to resolve carbon dioxide absorption signals on the order of 0.5%.

  17. EVALUATION OF SIGNIFICANT ANTHROPOGENIC SOURCES OF RADIATIVELY IMPORTANT TRACE GASES

    EPA Science Inventory

    The report is an initial evaluation of significant anthropogenic sources of radiatively important trace gases. missions of greenhouse gases from human activities--including fossil fuel combustion, industrial/agricultural activities, and transportation--contribute to the increasin...

  18. An Open-Path Tunable Diode Laser Sensor for Measurement of Greenhouse Gases at the Bonanza Creek Long Term Ecological Research Site near Fairbanks, Alaska

    NASA Astrophysics Data System (ADS)

    Bailey, D. Michelle; Adkins, Erin; Miller, Houston

    2016-04-01

    Permafrost makes up one-quarter of the Earth's terrestrial surface and, as global temperatures continue to increase, it is at risk of thawing. Thawing permafrost has the potential to release twice the amount of carbon than is currently in the atmosphere. A multi-year field campaign has begun in collaboration with the University of Alaska - Fairbanks, NASA Goddard Space Flight Center, and our group at George Washington University to study carbon feedbacks during a springtime thaw at the Bonanza Creek Long Term Ecological Research site near Fairbanks, Alaska. Here we present initial results from our near-infrared open-path instrument for the detection of ground-level concentrations of carbon dioxide (in subsequent field campaigns a second channel for methane detection will be added). The optics launch-box portion of the instrument couples a near-infrared distributed feedback laser operating near 1605 nm for carbon dioxide detection with a visible laser for alignment purposes. The outgoing beam is directed through a 3.2-mm hole in a parabolic mirror and the launch-box is oriented using a two axis, alt-azi telescope mount so that the beam will hit the retroreflector target at a set distance downfield. The beam then retraces the path back to the launch-box where the light is collected on the surface of the parabolic mirror and focused onto a multi-mode fiber for detection. Using a National Instruments data acquisition system we are able to collect 500 scans per second which allows for long-term data averaging and subsequently increases the signal-to-noise ratio (SNR) of our signal. In June 2015, the instrument was deployed to a thermokarst collapse scar bog in the Bonanza Creek Experimental Forest. With a 90 meter total pathlength we were able to resolve carbon dioxide absorption signals on the order of 0.5% utilizing direct-absorption spectroscopy. We also present the lab-scale implementation of wavelength modulation spectroscopy to increase the sensitivity of our

  19. The greenhouse trap

    SciTech Connect

    Lyman, F.; Mintzer, I.; Courrier, K.; MacKenzie, J.

    1990-01-01

    This book describes evidence of global warming and the contributions of man's activities to the process. The impacts of greenhouse gases on climate and health are discussed and recommendations are made for mitigation of these effects. Changes in fuel use, expansion of carbon sinks through planting of trees, and personal commitments to energy conservation are among these recommendations. Individual chapters were indexed separately for the data base.

  20. Greenhouse gas emissions and reactive nitrogen releases during the life-cycles of staple food production in China and their mitigation potential.

    PubMed

    Xia, Longlong; Ti, Chaopu; Li, Bolun; Xia, Yongqiu; Yan, Xiaoyuan

    2016-06-15

    Life-cycle analysis of staple food (rice, flour and corn-based fodder) production and assessments of the associated greenhouse gas (GHG) and reactive nitrogen (Nr) releases, from environmental and economic perspectives, help to develop effective mitigation options. However, such evaluations have rarely been executed in China. We evaluated the GHG and Nr releases per kilogram of staple food production (carbon and Nr footprints) and per unit of net economic benefit (CO2-NEB and Nr-NEB), and explored their mitigation potential. Carbon footprints of food production in China were obviously higher than those in some developed countries. There was a high spatial variation in the footprints, primarily attributable to differences in synthetic N use (or CH4 emissions) per unit of food production. Provincial carbon footprints had a significant linear relationship with Nr footprints, attributed to large contribution of N fertilizer use to both GHG and Nr releases. Synthetic N fertilizer applications and CH4 emissions dominated the carbon footprints, while NH3 volatilization and N leaching were the main contributors to the Nr footprints. About 564 (95% uncertainty range: 404-701) TgCO2eqGHG and 10 (7.4-12.4) Tg Nr-N were released every year during 2001-2010 from staple food production. This caused the total damage costs of 325 (70-555) billion ¥, equivalent to nearly 1.44% of the Gross Domestic Product of China. Moreover, the combined damage costs and economic input costs, accounted for 66%-80% of the gross economic benefit generated from food production. A reduction of 92.7TgCO2eqyr(-1) and 2.2TgNr-Nyr(-1) could be achieved by reducing synthetic N inputs by 20%, increasing grain yields by 5% and implementing off-season application of straw and mid-season drainage practices for rice cultivation. In order to realize these scenarios, an ecological compensation scheme should be established to incentivize farmers to gradually adopt knowledge-based managements. PMID:26971213

  1. Ozone depletion, greenhouse gases, and climate change

    NASA Technical Reports Server (NTRS)

    Mooney, Harold A.; Baker, D. James, Jr.; Bretherton, Francis P.; Burke, Kevin C.; Clark, William C.; Davis, Margaret B.; Dickinson, Robert E.; Imbrie, John; Malone, Thomas F.; Mcelroy, Michael B.

    1989-01-01

    This symposium was organized to study the unusual convergence of a number of observations, both short and long term that defy an integrated explanation. Of particular importance are surface temperature observations and observations of upper atmospheric temperatures, which have declined significantly in parts of the stratosphere. There has also been a dramatic decline in ozone concentration over Antarctica that was not predicted. Significant changes in precipitation that seem to be latitude dependent have occurred. There has been a threefold increase in methane in the last 100 years; this is a problem because a source does not appear to exist for methane of the right isotopic composition to explain the increase. These and other meteorological global climate changes are examined in detail.

  2. Analyzers Measure Greenhouse Gases, Airborne Pollutants

    NASA Technical Reports Server (NTRS)

    2012-01-01

    In complete darkness, a NASA observatory waits. When an eruption of boiling water billows from a nearby crack in the ground, the observatory s sensors seek particles in the fluid, measure shifts in carbon isotopes, and analyze samples for biological signatures. NASA has landed the observatory in this remote location, far removed from air and sunlight, to find life unlike any that scientists have ever seen. It might sound like a scene from a distant planet, but this NASA mission is actually exploring an ocean floor right here on Earth. NASA established a formal exobiology program in 1960, which expanded into the present-day Astrobiology Program. The program, which celebrated its 50th anniversary in 2010, not only explores the possibility of life elsewhere in the universe, but also examines how life begins and evolves, and what the future may hold for life on Earth and other planets. Answers to these questions may be found not only by launching rockets skyward, but by sending probes in the opposite direction. Research here on Earth can revise prevailing concepts of life and biochemistry and point to the possibilities for life on other planets, as was demonstrated in December 2010, when NASA researchers discovered microbes in Mono Lake in California that subsist and reproduce using arsenic, a toxic chemical. The Mono Lake discovery may be the first of many that could reveal possible models for extraterrestrial life. One primary area of interest for NASA astrobiologists lies with the hydrothermal vents on the ocean floor. These vents expel jets of water heated and enriched with chemicals from off-gassing magma below the Earth s crust. Also potentially within the vents: microbes that, like the Mono Lake microorganisms, defy the common characteristics of life on Earth. Basically all organisms on our planet generate energy through the Krebs Cycle, explains Mike Flynn, research scientist at NASA s Ames Research Center. This metabolic process breaks down sugars for energy to fuel cellular functions. "We think this chemical process did not exist when life first formed on Earth," he says, "because it is based on oxygen being available, and there was little oxygen available on the early Earth." It is possible that there are anaerobic regions beneath the sea floor in which life forms like those early non-Krebs Cycle microbes may yet exist. To detect and potentially collect samples of life emerging from hydrothermal vents, Flynn and his colleagues created Medusa, a multi-sensor instrument designed for long-term observation of diked vents on the ocean floor. When the vents erupt, Medusa assesses indicators of life within the expelled water. If the results are positive, the observatory collects samples and detaches from the ocean floor, making the long journey to the surface for retrieval by scientists. One of the indicators Medusa measures is the ratio of carbon isotopes in the water, namely carbon-12 and carbon-13. Living organisms preferentially take up carbon-12, Flynn says, so examining the ratio of these isotopes can help to determine the source of carbon in an environment as either biological or non-biological. "On Mars, there is evidence of localized methane in the atmosphere, and that methane could come from biological sources or from geochemical ones," Flynn says. "Determining the background planetary carbon isotope ratios and then evaluating the specific carbon ratios in this methane would help to determine how it was formed." A long-duration observatory similar to Medusa could one day provide essential evidence for or against the presence of life on the Red Planet or beneath the ice-crusted oceans of Europa.

  3. Greenhouse Gas Emissions from Pasture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carbon dioxide, nitrous oxide, and methane are the primary greenhouse gases associated with global climate change. Livestock production’s contribution to carbon dioxide emissions is minimal, but it is a substantial contributor to both nitrous oxide and methane emissions. In both grazing and confin...

  4. Microtrap assembly for greenhouse gas and air pollution monitoring

    SciTech Connect

    Mitra, Somenath; Saridara, Chutarat

    2015-08-25

    A microtrap assembly includes a carbon nanotube sorbent. The microtrap assembly may be employed as a preconcentrator operable to deliver a sample to an analytical device to measure the concentrations of greenhouse gases. A system includes a microtrap having a carbon nanotube sorbent for measuring the concentrations of greenhouse gases in a sample.

  5. Continuous multi-plot measurements of CO2, CH4, N2O and H2O in a managed boreal forest - The importance of accounting for all greenhouse gases

    NASA Astrophysics Data System (ADS)

    Vestin, P.; Mölder, M.; Sundqvist, E.; Båth, A.; Lehner, I.; Weslien, P.; Klemedtsson, L.; Lindroth, A.

    2015-12-01

    In order to assess the effects of different management practices on the exchange of greenhouse gases (GHG), it is desirable to perform repeated and parallel measurements on both experimental and control plots. Here we demonstrate how a system system combining eddy covariance and gradient techniques can be used to perform this assessment in a managed forest ecosystem.The net effects of clear-cutting and stump harvesting on GHG fluxes were studied at the ICOS site Norunda, Sweden. Micrometeorological measurements (i.e., flux-gradient measurements in 3 m tall towers) allowed for quantification of CO2, CH4 and H2O fluxes (from May 2010) as well as N2O and H2O fluxes (from June 2011) at two stump harvested plots and two control plots. There was one wetter and one drier plot of each treatment. Air was continuously sampled at two heights in the towers and gas concentrations were analyzed for CH4, CO2, H2O (LGR DLT-100, Los Gatos Research) and N2O, H2O (QCL Mini Monitor, Aerodyne Research). Friction velocities and sensible heat fluxes were measured by sonic anemometers (Gill Windmaster, Gill Instruments Ltd). Automatic chamber measurements (CO2, CH4, H2O) were carried out in the adjacent forest stand and at the clear-cut during 2010.Average CO2 emissions for the first year ranged between 14.4-20.2 ton CO2 ha-1 yr-1. The clear-cut became waterlogged after harvest and a comparison of flux-gradient data and chamber data (from the adjacent forest stand) indicated a switch from a weak CH4 sink to a significant source at all plots. The CH4 emissions ranged between 0.8-4.5 ton CO2-eq. ha-1 yr-1. N2O emissions ranged between 0.4-2.6 ton CO2-eq. ha-1 yr-1. Enhanced N2O emission on the drier stump harvested plot was the only clear treatment effect on GHG fluxes that was observed. Mean CH4 and N2O emissions for the first year of measurements amounted up to 29% and 20% of the mean annual CO2 emissions, respectively. This highlights the importance of including all GHGs

  6. Mitigating Greenhouse Gas Emissions: Voluntary Reporting 1996

    EIA Publications

    1997-01-01

    Presents information on voluntary actions to reduce greenhouse gases or remove such gases from the atmosphere in 1995. It provides an overview of participation in the Voluntary Reporting Program, a perspective on the composition of activities reported, and a review of some key issues in interpreting and evaluating achievements associated with reported emissions mitigation initiatives.

  7. Episodic vs. epochal release of SO2 on Mars

    NASA Technical Reports Server (NTRS)

    Postawko, S. E.; Fanale, F. P.; Zent, A. P.

    1987-01-01

    Erosion of the Martian surface by the flow of liquid water has apparently taken place at different times and locations on the planet. Many attempts were made to explain the valley networks by invoking a strong atmospheric CO2/H2O greenhouse early in the history of the planet. It was assumed that the large amounts of CO2 necessary to cause the greenhouse would have disappeared due to carbonate formation. Carbonates have yet to be positively identified. Volcanism has occurred throughout much of the history of Mars. Presumably gases such as SO2 were released along with CO2 and H2O. Estimates of amounts and rates with which SO2 were released into the Martian atmosphere, and how this would effect the global climate were made. Studies are continuing on the effects of SO2 and other volcanic gases on Martian climatic history.

  8. Greenhouse-gas emissions from soils increased by earthworms

    NASA Astrophysics Data System (ADS)

    Lubbers, Ingrid M.; van Groenigen, Kees Jan; Fonte, Steven J.; Six, Johan; Brussaard, Lijbert; van Groenigen, Jan Willem

    2013-03-01

    Earthworms play an essential part in determining the greenhouse-gas balance of soils worldwide, and their influence is expected to grow over the next decades. They are thought to stimulate carbon sequestration in soil aggregates, but also to increase emissions of the main greenhouse gases carbon dioxide and nitrous oxide. Hence, it remains highly controversial whether earthworms predominantly affect soils to act as a net source or sink of greenhouse gases. Here, we provide a quantitative review of the overall effect of earthworms on the soil greenhouse-gas balance. Our results suggest that although earthworms are largely beneficial to soil fertility, they increase net soil greenhouse-gas emissions.

  9. Overview of global greenhouse effects

    SciTech Connect

    Reck, R.A.

    1993-09-01

    This report reviews the factors that influence the evolution of climate and climate change. Recent studies have confirmed that CO{sub 2}, O{sub 3}, N{sub 2}O, CH{sub 4}, and chlorofluorocarbos are increasing in abundance in the atmosphere and can alter the radiation balance by means of the so-called greenhouse effect. The greenhouse effect is as well-accepted phenomenon, but the prediction of its consequences is much less certain. Attempts to detect a human-caused temperature change are still inconclusive. This report presents a discussion of the scientific basis for the greenhouse effect, its relationship to the abundances of greenhouse gases, and the evidence confirming the increases in the abundances. The basis for climate modeling is presented together with an example of the model outputs from one of the most sophisticated modeling efforts. Uncertainties in the present understanding of climate are outlined.

  10. Noble gases in the moon

    NASA Technical Reports Server (NTRS)

    Manuel, O. K.; Srinivasan, B.; Hennecke, E. W.; Sinclair, D. E.

    1972-01-01

    The abundance and isotopic composition of helium, neon, argon, krypton, and xenon which were released by stepwise heating of lunar fines (15601.64) and (15271.65) were measured spectrometrically. The results of a composition of noble gases released from the lunar fines with noble gases in meteorites and in the earth are presented along with the isotopic composition of noble gases in lunar fines, in meteorites, and in the atmosphere. A study of two isotopically distinct components of trapped xenon in carbonaceous chondrites is also included.

  11. Observational determination of the greenhouse effect

    NASA Technical Reports Server (NTRS)

    Raval, A.; Ramanathan, V.

    1989-01-01

    Satellite measurements are used to quantify the atmospheric greenhouse effect, defined here as the infrared radiation energy trapped by atmospheric gases and clouds. The greenhouse effect is found to increase significantly with sea surface temperature. The rate of increase gives compelling evidence for the positive feedback between surface temperature, water vapor and the greenhouse effect; the magnitude of the feedback is consistent with that predicted by climate models. This study demonstrates an effective method for directly monitoring, from space, future changes in the greenhouse effect.

  12. The potential for biomass to mitigate greenhouse gas emissions in the Northeastern US

    SciTech Connect

    Bernow, S.S.; Gurney, K.; Prince, G.; Cyr, M.

    1992-04-01

    This study, for the Northeast Regional Biomass Program (NRBP) of the Coalition of Northeast Governors (CONEG), evaluates the potential for local, state and regional biomass policies to contribute to an overall energy/biomass strategy for the reduction of greenhouse gas releases in the Northeastern United States. Biomass is a conditionally renewable resource that can play a dual role: by reducing emissions of greenhouse gases in meeting our energy needs; and by removing carbon from the atmosphere and sequestering it in standing biomass stocks and long-lived products. In this study we examine the contribution of biomass to the energy system in the Northeast and to the region's net releases of carbon dioxide and methane, and project these releases over three decades, given a continuation of current trends and policies. We then compare this Reference Case with three alternative scenarios, assuming successively more aggressive efforts to reduce greenhouse gas emissions through strategic implementation of energy efficiency and biomass resources. Finally, we identify and examine policy options for expanding the role of biomass in the region's energy and greenhouse gas mitigation strategies.

  13. Study of the Effects on Student Knowledge and Perceptions of Activities Related to Submetering the 6th Grade Wing of a Middle School, to Displaying the Carbon Footprint, and to Efforts to Reduce Energy Consumption and Greenhouse Gases

    ERIC Educational Resources Information Center

    Peck, Rick

    2009-01-01

    The purpose of the study was to determine the effects upon student knowledge and perceptions regarding greenhouse gas emissions as a result of an intervention relying upon the submetering the 6th grade wing of a Middle School, displaying the information regarding electrical consumption and carbon footprint, and reducing the electrical consumption…

  14. Greenhouse gas emissions from a managed grassland

    NASA Astrophysics Data System (ADS)

    Jones, S. K.; Rees, R. M.; Skiba, U. M.; Ball, B. C.

    2005-07-01

    Managed grasslands contribute to global warming by the exchange of the greenhouse gases carbon dioxide, nitrous oxide and methane. To reduce uncertainties of the global warming potential of European grasslands and to assess potential mitigation options, an integrated approach quantifying fluxes from all three gases is needed. Greenhouse gas emissions from a grassland site in the SE of Scotland were measured in 2002 and 2003. Closed static chambers were used for N 2O and CH 4 flux measurements, and samples were analysed by gas chromatography. Closed dynamic chambers were used for soil respiration measurements, using infrared gas analysis. Three organic manures and two inorganic fertilizers were applied at a rate of 300 kg N ha -1 a -1 (available N) and compared with a zero-N control on grassland plots in a replicated experimental design. Soil respiration from plots receiving manure was up to 1.6 times larger than CO 2 release from control plots and up to 1.7 times larger compared to inorganic treatments ( p<0.05). A highly significant ( p<0.001) effect of fertilizer and manure treatments on N 2O release was observed. Release of N 2O from plots receiving inorganic fertilizers resulted in short term peaks of up to 388 g N 2O-N ha -1 day -1. However losses from plots receiving organic manures were both longer lasting and greater in magnitude, with an emission of up to 3488 g N 2O-N ha -1 day -1 from the sewage sludge treatments. During the 2002 growing season the cumulative total N 2O flux from manure treatments was 25 times larger than that from mineral fertilizers. CH 4 emissions were only significantly increased ( p<0.001) for a short period following applications of cattle slurry. Although soil respiration in manure plots was high, model predictions and micrometeorological flux measurements at an adjacent site suggest that all plots receiving fertilizer or manure acted as a sink for CO 2. Therefore in terms of global warming potentials the contribution of N 2O from

  15. Greenhouse gas emissions associated with direct energy inputs for a warmwater low-salinity recirculating aquaculture systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Greenhouse gases (GHGs) are gases that trap heat in the atmosphere. These gases include carbon dioxide (CO2), methane (CH3), nitrous oxide (N2O), and fluorinated gases. Some of these gases occur naturally and some are created by human activities which can increase their concentrations. The most comm...

  16. Energy Market Impacts of Alternative Greenhouse Gas Intensity Reduction Goals

    EIA Publications

    2006-01-01

    This report responds to a request from Senator Ken Salazar that the Energy Information Administration (EIA) analyze the impacts of implementing alternative variants of an emissions cap-and-trade program for greenhouse gases (GHGs).

  17. Toxic gases.

    PubMed Central

    Matthews, G.

    1989-01-01

    An overview of the widespread use of gases and some volatile solvents in modern society is given. The usual circumstances in which undue exposure may occur are described. The most prominent symptoms and general principles of diagnosis and treatment are given and are followed by more specific information on the commoner, more toxic materials. While acute poisonings constitute the greater part of the paper, some indication of chronic disorders arising from repeated or prolonged exposure is also given. PMID:2687827

  18. Noble Gases

    NASA Astrophysics Data System (ADS)

    Podosek, F. A.

    2003-12-01

    The noble gases are the group of elements - helium, neon, argon, krypton, xenon - in the rightmost column of the periodic table of the elements, those which have "filled" outermost shells of electrons (two for helium, eight for the others). This configuration of electrons results in a neutral atom that has relatively low electron affinity and relatively high ionization energy. In consequence, in most natural circumstances these elements do not form chemical compounds, whence they are called "noble." Similarly, much more so than other elements in most circumstances, they partition strongly into a gas phase (as monatomic gas), so that they are called the "noble gases" (also, "inert gases"). (It should be noted, of course, that there is a sixth noble gas, radon, but all isotopes of radon are radioactive, with maximum half-life a few days, so that radon occurs in nature only because of recent production in the U-Th decay chains. The factors that govern the distribution of radon isotopes are thus quite different from those for the five gases cited. There are interesting stories about radon, but they are very different from those about the first five noble gases, and are thus outside the scope of this chapter.)In the nuclear fires in which the elements are forged, the creation and destruction of a given nuclear species depends on its nuclear properties, not on whether it will have a filled outermost shell when things cool off and nuclei begin to gather electrons. The numerology of nuclear physics is different from that of chemistry, so that in the cosmos at large there is nothing systematically special about the abundances of the noble gases as compared to other elements. We live in a very nonrepresentative part of the cosmos, however. As is discussed elsewhere in this volume, the outstanding generalization about the geo-/cosmochemistry of the terrestrial planets is that at some point thermodynamic conditions dictated phase separation of solids from gases, and that the

  19. Greenhouse gas emissions related to ethanol produced from corn

    SciTech Connect

    Marland, G.

    1994-04-01

    This report confers the details of a panel meeting discussion on greenhouse gases. The topic of this discussion was ethanol. Members discussed all aspects of growing corn and producing ethanol. Then the question was raised as to whether or not this is a suitable substitute to fossil fuel usage in the reduction of greenhouse gas emissions.

  20. Greenhouse gas emissions from soil under changing environmental conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This manuscript is the Guest Editors’ Introduction to a special issue on greenhouse gas emissions from agriculture. The papers were assembled following presentation at EuroSoil 2012. Exchange of greenhouse gases between soils and the atmosphere is a natural consequence of several ecosystem process...

  1. Greenhouse Effect Detection Experiment (GEDEX). Selected data sets

    NASA Technical Reports Server (NTRS)

    Olsen, Lola M.; Warnock, Archibald, III

    1992-01-01

    This CD-ROM contains selected data sets compiled by the participants of the Greenhouse Effect Detection Experiment (GEDEX) workshop on atmospheric temperature. The data sets include surface, upper air, and/or satellite-derived measurements of temperature, solar irradiance, clouds, greenhouse gases, fluxes, albedo, aerosols, ozone, and water vapor, along with Southern Oscillation Indices and Quasi-Biennial Oscillation statistics.

  2. RECONSTRUCTION OF EXTERNAL DOSES TO OZYORSK RESIDENTS DUE TO ATMOSPHERIC RELEASES OF INERT RADIOACTIVE GASES FROM THE STACKS OF THE “MAYAK” PA REACTOR PLANT FROM 1948 TO 1989

    SciTech Connect

    Glagolenko, Y. V.; Drozhko, Evgeniy G.; Mokrov, Y.; Rovny, Sergey I.; Beregich, D. A.; Stukalov, Pavel M.; Ivanov, I. A.; Alexakhin, A. I.; Anspaugh, L. R.; Napier, Bruce A.

    2008-06-01

    The article provides the results of reconstruction of external doses to population due to atmospheric releases of inert radioactive gases of activation (41Ar) and fission origin (xenon and krypton isotopes) from the stacks of the “Mayak” PA industrial reactors from 1948 to 1989. Calculation of surface volumetric activities was performed using the RATCHET code. Dose estimate was obtained in a semi-infinite cloud approximation. It is demonstrated that more than 90% of external dose was accumulated from 1948 to 1956. It is established that, generally, the calculation results are in good agreement with archive instrument monitoring data on exposure dose rate and thermoluminescence dosimetry data. External effective doses to the residents of Ozyorsk obtained for different age groups of population with consideration of shielding properties of buildings and duration of time spent outdoors were estimated in the range from 16 to 23 mSv.

  3. Greenhouse-gas emissions from biofuel use in Asia.

    SciTech Connect

    Streets, D. G.; Waldhoff, S. T.

    1999-07-06

    Biomass is a primary fuel for much of the world's population. In some developing countries it can contribute 80-90% of total primary energy consumption. In Asia as a whole we estimate that biomass contributes about 22 EJ, almost 24% of total energy use. Much of this biomass is combusted in inefficient domestic stoves and cookers, enhancing the formation of products of incomplete combustion (PIC), many of which are greenhouse gases. An inventory of the combustion of biofuels (fuelwood, crop residues, and dried animal waste) in Asia is used to develop estimates of the emissions of carbon-containing greenhouse gases (CO{sub 2},CO, CH{sub 4}, and NMHC) in Asian countries. The data are examined from two perspectives: total carbon released and total global warming potential (GWP) of the gases. We estimate that blofuels contributed 573 Tg-C in 1990, about 28% of the total carbon emissions from energy use in Asia. China (259 Tg-C) and India (187 Tg-C) were the largest emitting countries by far. The majority of the emissions, 504 Tg-C, are in the form of CO{sub 2}; however, emissions of non-CO{sub 2} greenhouse gases are significant: 57 Tg-C as CO, 6.4 Tg-C as CH{sub 4}, and 5.9 Tg-C as NMHC. Because of the high rate of incomplete combustion in typical biofuel stoves and the high GWP coefficients of the products of incomplete combustion, biofuels comprise an even larger share of energy-related emissions when measured in terms of global warming potential (in CO{sub 2} equivalents): 38% over a 20-year time frame and 31% over 100 years. Even when the biofuel is assumed to be harvested on a completely sustainable basis (all CO{sub 2} emissions are reabsorbed in the following growing season), PIC emissions from biofuel combustion account for almost 5% of total carbon emissions and nearly 25% of CO{sub 2} equivalents in terms of short-term (20-year) GWP.

  4. Policy Analysis of the Greenhouse Effect (PAGE)

    EPA Science Inventory

    PAGE09 is a spreadsheet probabilistic model written in Microsoft Office Excel. The model ca