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20 results on '"global methane budget"'

1. Global and Regional CH4 Emissions for 1995–2013 Derived From Atmospheric CH4, δ13C‐CH4, and δD‐CH4 Observations and a Chemical Transport Model.

Author

Fujita, Ryo, Morimoto, Shinji, Maksyutov, Shamil, Kim, Heon‐Sook, Arshinov, Mikhail, Brailsford, Gordon, Aoki, Shuji, and Nakazawa, Takakiyo

Subjects
FOSSIL fuels, BIOMASS, HEAT flux, CLIMATOLOGY, CLIMATE change
Abstract

To better understand the current global CH4 budget, biogenic, fossil fuel, and biomass burning CH4 fluxes for the period 1995–2013 were inversely estimated from the observed mole fraction data of atmospheric CH4 using a three‐dimensional chemical transport model. Then, forward simulations of carbon and hydrogen isotope ratios of atmospheric CH4 (δ13C‐CH4 and δD‐CH4) were conducted using the inversion fluxes to evaluate the source proportion of the global total CH4 emission. Model‐simulated spatiotemporal variations of atmospheric CH4 reproduce the observational results well; however, the simulated δ13C‐CH4 and δD‐CH4 values significantly underestimate their observed values as a whole. This implies that the proportion of biogenic CH4 sources in the global CH4 emission, deduced by inverse modeling, is overestimated, although the proportion is fairly comparable with the medians of recent multiple CH4 inverse modeling. To reduce the disagreement between the observed and calculated isotope ratios, the CH4 fluxes of individual source categories were adjusted using our atmospheric δ13C‐CH4 and δD‐CH4 data observed at Arctic and Antarctic surface stations. The resultant global average biogenic, fossil fuel, and biomass burning CH4 fluxes over 2003–2012 are 346 ± 11, 162 ± 2, and 50 ± 2 TgCH4 year−1, respectively. It is also strongly suggested that the leveling‐off of atmospheric CH4 in the early 2000s and the renewed growth after 2006/2007 are, respectively, explainable by the decrease in biogenic and biomass burning CH4 emissions for 2000–2006 and the increase in biogenic CH4 emissions after that period. These emission changes mainly originate in the tropics. Key Points: Inverse modeling of atmospheric CH4 and forward simulations of its δ13C and δD are made to estimate surface CH4 emissions for 1995–2013The forward simulations reveal that the proportion of biogenic CH4 in global emission, deduced by the inverse modeling, is overestimatedThe plateau and regrowth of atmospheric CH4 in the 2000s are closely related with biogenic and biomass burning CH4 emissions in the tropics [ABSTRACT FROM AUTHOR]

Published
2020
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2. MERLIN: A French-German Space Lidar Mission Dedicated to Atmospheric Methane.

Author

Ehret, Gerhard, Bousquet, Philippe, Pierangelo, Clémence, Alpers, Matthias, Millet, Bruno, Abshire, James B., Bovensmann, Heinrich, Burrows, John P., Chevallier, Frédéric, Ciais, Philippe, Crevoisier, Cyril, Fix, Andreas, Flamant, Pierre, Frankenberg, Christian, Gibert, Fabien, Heim, Birgit, Heimann, Martin, Houweling, Sander, Hubberten, Hans W., and Jöckel, Patrick

Subjects
*ATMOSPHERIC methane, *LIDAR, *REMOTE sensing, *EMISSIONS (Air pollution), *GREENHOUSE gases
Abstract

The MEthane Remote sensing Lidar missioN (MERLIN) aims at demonstrating the spaceborne active measurement of atmospheric methane, a potent greenhouse gas, based on an Integrated Path Differential Absorption (IPDA) nadir-viewing LIght Detecting and Ranging (Lidar) instrument. MERLIN is a joint French and German space mission, with a launch currently scheduled for the timeframe 2021/22. The German Space Agency (DLR) is responsible for the payload, while the platform (MYRIADE Evolutions product line) is developed by the French Space Agency (CNES). The main scientific objective of MERLIN is the delivery of weighted atmospheric columns of methane dry-air mole fractions for all latitudes throughout the year with systematic errors small enough (<3.7 ppb) to significantly improve our knowledge of methane sources from global to regional scales, with emphasis on poorly accessible regions in the tropics and at high latitudes. This paper presents the MERLIN objectives, describes the methodology and the main characteristics of the payload and of the platform, and proposes a first assessment of the error budget and its translation into expected uncertainty reduction of methane surface emissions. [ABSTRACT FROM AUTHOR]

Published
2017
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4. Enhanced response of global wetland methane emissions to the 2015–2016 El Niño-Southern Oscillation event

Author

Zhen Zhang, Niklaus E Zimmermann, Leonardo Calle, George Hurtt, Abhishek Chatterjee, and Benjamin Poulter

Subjects
DGVM, global methane budget, ENSO, greenhouse gas, Environmental technology. Sanitary engineering, TD1-1066, Environmental sciences, GE1-350, Science, Physics, QC1-999
Abstract

Wetlands are thought to be the major contributor to interannual variability in the growth rate of atmospheric methane (CH _4 ) with anomalies driven by the influence of the El Niño-Southern Oscillation (ENSO). Yet it remains unclear whether (i) the increase in total global CH _4 emissions during El Niño versus La Niña events is from wetlands and (ii) how large the contribution of wetland CH _4 emissions is to the interannual variability of atmospheric CH _4 . We used a terrestrial ecosystem model that includes permafrost and wetland dynamics to estimate CH _4 emissions, forced by three separate meteorological reanalyses and one gridded observational climate dataset, to simulate the spatio-temporal dynamics of wetland CH _4 emissions from 1980–2016. The simulations show that while wetland CH _4 responds with negative annual anomalies during the El Niño events, the instantaneous growth rate of wetland CH _4 emissions exhibits complex phase dynamics. We find that wetland CH _4 instantaneous growth rates were declined at the onset of the 2015–2016 El Niño event but then increased to a record-high at later stages of the El Niño event (January through May 2016). We also find evidence for a step increase of CH _4 emissions by 7.8±1.6 Tg CH _4 yr ^−1 during 2007–2014 compared to the average of 2000–2006 from simulations using meteorological reanalyses, which is equivalent to a ~3.5 ppb yr ^−1 rise in CH _4 concentrations. The step increase is mainly caused by the expansion of wetland area in the tropics (30°S–30°N) due to an enhancement of tropical precipitation as indicated by the suite of the meteorological reanalyses. Our study highlights the role of wetlands, and the complex temporal phasing with ENSO, in driving the variability and trends of atmospheric CH _4 concentrations. In addition, the need to account for uncertainty in meteorological forcings is highlighted in addressing the interannual variability and decadal-scale trends of wetland CH _4 fluxes.

Published
2018
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5. MERLIN: A French-German Space Lidar Mission Dedicated to Atmospheric Methane

Author

Gerhard Ehret, Philippe Bousquet, Clémence Pierangelo, Matthias Alpers, Bruno Millet, James B. Abshire, Heinrich Bovensmann, John P. Burrows, Frédéric Chevallier, Philippe Ciais, Cyril Crevoisier, Andreas Fix, Pierre Flamant, Christian Frankenberg, Fabien Gibert, Birgit Heim, Martin Heimann, Sander Houweling, Hans W. Hubberten, Patrick Jöckel, Kathy Law, Alexander Löw, Julia Marshall, Anna Agusti-Panareda, Sebastien Payan, Catherine Prigent, Patrick Rairoux, Torsten Sachs, Marko Scholze, and Martin Wirth

Subjects
MERLIN, space mission, IPDA Lidar, atmospheric methane, CH4 emissions, global methane budget, Science
Abstract

The MEthane Remote sensing Lidar missioN (MERLIN) aims at demonstrating the spaceborne active measurement of atmospheric methane, a potent greenhouse gas, based on an Integrated Path Differential Absorption (IPDA) nadir-viewing LIght Detecting and Ranging (Lidar) instrument. MERLIN is a joint French and German space mission, with a launch currently scheduled for the timeframe 2021/22. The German Space Agency (DLR) is responsible for the payload, while the platform (MYRIADE Evolutions product line) is developed by the French Space Agency (CNES). The main scientific objective of MERLIN is the delivery of weighted atmospheric columns of methane dry-air mole fractions for all latitudes throughout the year with systematic errors small enough (

Published
2017
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6. Enhanced response of global wetland methane emissions to the 2015-2016 El Niño-Southern Oscillation event

Author

Abhishek Chatterjee, Niklaus E. Zimmermann, Leonardo Calle, Benjamin Poulter, Zhen Zhang, and George C. Hurtt

Subjects
DGVM, global methane budget, ENSO, greenhouse gas, geography, geography.geographical_feature_category, 010504 meteorology & atmospheric sciences, Renewable Energy, Sustainability and the Environment, Atmospheric methane, Public Health, Environmental and Occupational Health, Tropics, Wetland, 010502 geochemistry & geophysics, Atmospheric sciences, Permafrost, 01 natural sciences, Article, La Niña, El Niño Southern Oscillation, Greenhouse gas, Environmental science, Wetland methane emissions, 0105 earth and related environmental sciences, General Environmental Science
Abstract

Wetlands are thought to be the major contributor to interannual variability in the growth rate of atmospheric methane (CH4) with anomalies driven by the influence of the El Niño-Southern Oscillation (ENSO). Yet it remains unclear whether (i) the increase in total global CH4 emissions during El Niño versus La Niña events is from wetlands and (ii) how large the contribution of wetland CH4 emissions is to the interannual variability of atmospheric CH4. We used a terrestrial ecosystem model that includes permafrost and wetland dynamics to estimate CH4 emissions, forced by three separate meteorological reanalyses and one gridded observational climate dataset, to simulate the spatio-temporal dynamics of wetland CH4 emissions from 1980–2016. The simulations show that while wetland CH4 responds with negative annual anomalies during the El Niño events, the instantaneous growth rate of wetland CH4 emissions exhibits complex phase dynamics. We find that wetland CH4 instantaneous growth rates were declined at the onset of the 2015–2016 El Niño event but then increased to a record-high at later stages of the El Niño event (January through May 2016). We also find evidence for a step increase of CH4 emissions by 7.8±1.6 Tg CH4 yr−1 during 2007–2014 compared to the average of 2000–2006 from simulations using meteorological reanalyses, which is equivalent to a ~3.5 ppb yr−1 rise in CH4 concentrations. The step increase is mainly caused by the expansion of wetland area in the tropics (30°S–30°N) due to an enhancement of tropical precipitation as indicated by the suite of the meteorological reanalyses. Our study highlights the role of wetlands, and the complex temporal phasing with ENSO, in driving the variability and trends of atmospheric CH4 concentrations. In addition, the need to account for uncertainty in meteorological forcings is highlighted in addressing the interannual variability and decadal-scale trends of wetland CH4 fluxes., Environmental Research Letters, 13 (7), ISSN:1748-9326, ISSN:1748-9318

Published
2020

7. Microbial methane turnover in different marine habitats

Author

Krüger, Martin, Treude, Tina, Wolters, Heike, Nauhaus, Katja, and Boetius, Antje

Subjects
*METHANOGENS, *ALKANES, *MANURE gases, *METHANE
Abstract

Abstract: Microbial methanogenesis in the subsurface seafloor is responsible for the formation of large and dynamic gas reservoirs like the recently discovered gas hydrate deposits. Gas seepage occurs wherever methane builds up an overpressure outside the hydrate stability field, illustrating the potential importance of ocean margins for the global methane budget. However, a variety of bacteria and archaea are capable of methane consumption, and control the emission of methane to the hydrosphere. Unfortunately, much less is known about the microbial methane turnover in the ocean than about methane turnover in freshwater or terrestrial habitats. This investigation compares rates of methane production, anaerobic and aerobic methane oxidation at different marine sites, combining radiotracer (on-site) and in vitro measurements. Samples were obtained from gas hydrate bearing sediments, cold seeps, organic-rich and organic-poor subsurface sediments. All investigated subsurface sediments had the potential for methanogenesis as well as for methanotrophy. The anaerobic oxidation of methane (AOM) was highest in samples from gas hydrate areas and cold seeps. AOM was strongly influenced by methane partial pressure and temperature, indicating a substantial underestimation of in situ activity with current ex situ measuring techniques. A potential for aerobic methane oxidation was detected at all sites where the sediment had contact with oxic bottom water. A first comparison of methane turnover rates in diverse marine habitats showed that microbial methane oxidation provides a very effective barrier for methane emissions from the subsurface seafloor. [Copyright &y& Elsevier]

Published
2005
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8. Error Budget of the MEthane Remote LIdar missioN and Its Impact on the Uncertainties of the Global Methane Budget

Author

Bruno Millet, Achim Friker, Patrick Rairoux, Christoph Kiemle, Cyril Crevoisier, Andreas Fix, Vincent Cassé, Mathias Alpers, Frederic Esteve, Martin Wirth, Frédéric Chevallier, Fabien Gibert, Gerhard Ehret, Clémence Pierangelo, Julia Marshall, Cédric Bacour, Jordi Chinaud, Caroline Bes, Thibault Delahaye, François-Marie Bréon, A. Klonecki, R. Armante, Pradeebane Vaittinada Ayar, Olivier Chomette, Dimitri Edouart, Philippe Bousquet, Philippe Peylin, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Modélisation INVerse pour les mesures atmosphériques et SATellitaires (SATINV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Centre National d'Études Spatiales [Toulouse] (CNES), NOVELTIS [Sté], Max-Planck-Institut für Biogeochemie (MPI-BGC), Modélisation des Surfaces et Interfaces Continentales (MOSAIC), DLR Institut für Physik der Atmosphäre (IPA), Deutsches Zentrum für Luft- und Raumfahrt [Oberpfaffenhofen-Wessling] (DLR), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Institut Lumière Matière [Villeurbanne] (ILM), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon, Deutsches Zentrum für Luft- und Raumfahrt [Bonn] (DLR), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)

Subjects
Atmospheric Science, 010504 meteorology & atmospheric sciences, Meteorology, methane emissions, 010502 geochemistry & geophysics, 01 natural sciences, atmospheric methane, global methane budget, Methane, Latitude, chemistry.chemical_compound, inversion, Earth and Planetary Sciences (miscellaneous), Uncertainty reduction theory, 0105 earth and related environmental sciences, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Lidar, Atmospheric methane, Inversion (meteorology), Ranging, uncertainties, error budget, Impact study, MERLIN, Geophysics, chemistry, 13. Climate action, Space and Planetary Science, Greenhouse gas, Environmental science, Raumfahrtmanagement, space-based Lidar, MERLIN mission
Abstract

International audience; MEthane Remote LIdar missioN (MERLIN) is a German‐French space mission, scheduled for launch in 2024 and built around an innovative light detecting and ranging instrument that will retrieve methane atmospheric weighted columns. MERLIN products will be assimilated into chemistry transport models to infer methane emissions and sinks. Here the expected performance of MERLIN to reduce uncertainties on methane emissions is estimated. A first complete error budget of the mission is proposed based on an analysis of the plausible causes of random and systematic errors. Systematic errors are spatially and temporally distributed on geophysical variables and then aggregated into an ensemble of 32 scenarios. Observing System Simulation Experiments are conducted, originally carrying both random and systematic errors. Although relatively small (±2.9 ppb), systematic errors are found to have a larger influence on MERLIN performances than random errors. The expected global mean uncertainty reduction on methane emissions compared to the prior knowledge is found to be 32%, limited by the impact of systematic errors. The uncertainty reduction over land reaches 60% when the largest desert regions are removed. At the latitudinal scale, the largest uncertainty reductions are achieved for temperate regions (84%) and then tropics (56%) and high latitudes (53%). Similar Observing System Simulation Experiments based on error scenarios for Greenhouse Gases Observing SATellite reveal that MERLIN should perform better than Greenhouse Gases Observing SATellite for most continental regions. The integration of error scenarios for MERLIN in another inversion system suggests similar results, albeit more optimistic in terms of uncertainty reduction.

Published
2018
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9. MERLIN

Subjects
Atmospheric methane, SDG 13 - Climate Action, CH emissions, IPDA Lidar, Global methane budget, Space mission, MERLIN
Abstract

The MEthane Remote sensing Lidar missioN (MERLIN) aims at demonstrating the spaceborne active measurement of atmospheric methane, a potent greenhouse gas, based on an Integrated Path Differential Absorption (IPDA) nadir-viewing LIght Detecting and Ranging (Lidar) instrument. MERLIN is a joint French and German space mission, with a launch currently scheduled for the timeframe 2021/22. The German Space Agency (DLR) is responsible for the payload, while the platform (MYRIADE Evolutions product line) is developed by the French Space Agency (CNES). The main scientific objective of MERLIN is the delivery of weighted atmospheric columns of methane dry-air mole fractions for all latitudes throughout the year with systematic errors small enough (< 3.7 ppb) to significantly improve our knowledge of methane sources from global to regional scales, with emphasis on poorly accessible regions in the tropics and at high latitudes. This paper presents the MERLIN objectives, describes the methodology and the main characteristics of the payload and of the platform, and proposes a first assessment of the error budget and its translation into expected uncertainty reduction of methane surface emissions.

Published
2017

10. MERLIN: A French-German Space Lidar Mission Dedicated to Atmospheric Methane

Author

Cyril Crevoisier, Bruno Millet, Anna Agusti-Panareda, Alexander Löw, Clémence Pierangelo, Hans-Wolfgang Hubberten, Patrick Rairoux, Philippe Ciais, Pierre H. Flamant, Birgit Heim, Torsten Sachs, Christian Frankenberg, Andreas Fix, Patrick Jöckel, John P. Burrows, Marko Scholze, Martin Wirth, Sander Houweling, Martin Heimann, Frédéric Chevallier, Heinrich Bovensmann, Sébastien Payan, Gerhard Ehret, Julia Marshall, Matthias Alpers, Kathy S. Law, Fabien Gibert, Catherine Prigent, James B. Abshire, Philippe Bousquet, DLR Institut für Physik der Atmosphäre (IPA), Deutsches Zentrum für Luft- und Raumfahrt [Oberpfaffenhofen-Wessling] (DLR), Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Modélisation INVerse pour les mesures atmosphériques et SATellitaires (SATINV), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Centre National d'Études Spatiales [Toulouse] (CNES), Deutsches Zentrum für Luft- und Raumfahrt (DLR), NASA Goddard Space Flight Center (GSFC), Institut für Umweltphysik [Bremen] (IUP), Universität Bremen, ICOS-ATC (ICOS-ATC), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École des Ponts ParisTech (ENPC)-École polytechnique (X)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), TROPO - LATMOS, Laboratoire Atmosphères, Milieux, Observations Spatiales (LATMOS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Tropospheric sounding, assimilation, and modeling group [JPL], Jet Propulsion Laboratory (JPL), California Institute of Technology (CALTECH)-NASA-California Institute of Technology (CALTECH)-NASA, Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Max-Planck-Institut für Biogeochemie (MPI-BGC), Department of Physics [Helsinki], Falculty of Science [Helsinki], University of Helsinki-University of Helsinki, SRON Netherlands Institute for Space Research (SRON), Vrije Universiteit Amsterdam [Amsterdam] (VU), Department of Earth Sciences [Amsterdam], VU University Amsterdam, Department of Geography [München], Ludwig-Maximilians-Universität München (LMU), Max-Planck-Institut für Biochemie (MPIB), Max-Planck-Gesellschaft, European Centre for Medium-Range Weather Forecasts (ECMWF), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Institut Lumière Matière [Villeurbanne] (ILM), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), GeoForschungsZentrum - Helmholtz-Zentrum Potsdam (GFZ), Department of Physical Geography and Ecosystem Science [Lund], Lund University [Lund], Vrije universiteit = Free university of Amsterdam [Amsterdam] (VU), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), NASA-California Institute of Technology (CALTECH)-NASA-California Institute of Technology (CALTECH), Helsingin yliopisto = Helsingfors universitet = University of Helsinki-Helsingin yliopisto = Helsingfors universitet = University of Helsinki, and Max-Planck-Institut für Biochemie = Max Planck Institute of Biochemistry (MPIB)

Subjects
CH4 emissions, 010504 meteorology & atmospheric sciences, Meteorology, Science, Global methane budget, space mission, Space mission, 7. Clean energy, 01 natural sciences, global methane budget, atmospheric methane, Methane, 010309 optics, chemistry.chemical_compound, 0103 physical sciences, SDG 13 - Climate Action, Mixing ratio, MERLIN, 0105 earth and related environmental sciences, Remote sensing, [PHYS.PHYS.PHYS-AO-PH]Physics [physics]/Physics [physics]/Atmospheric and Oceanic Physics [physics.ao-ph], Lidar, Atmospheric methane, Payload, IPDA Lidar, SCIAMACHY, chemistry, greenhouse gas, 13. Climate action, Greenhouse gas, CH emissions, General Earth and Planetary Sciences, Environmental science, Raumfahrtmanagement
Abstract

International audience; The MEthane Remote sensing Lidar missioN (MERLIN) aims at demonstrating the spaceborne active measurement of atmospheric methane, a potent greenhouse gas, based on an Integrated Path Differential Absorption (IPDA) nadir-viewing LIght Detecting and Ranging (Lidar) instrument. MERLIN is a joint French and German space mission, with a launch currently scheduled for the timeframe 2021/22. The German Space Agency (DLR) is responsible for the payload, while the platform (MYRIADE Evolutions product line) is developed by the French Space Agency (CNES). The main scientific objective of MERLIN is the delivery of weighted atmospheric columns of methane dry-air mole fractions for all latitudes throughout the year with systematic errors small enough (

Published
2017
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11. Are plants precursors for methane?

Author

Dueck, Tom and Van der Werf, Adrie

Subjects
*METHANE, *PLANTS & the environment, *PECTINS, *EMISSIONS (Air pollution), EDITORIALS
Abstract

The authors comment on a study published within the issue which claimed that plants produce methane under aerobic conditions. The paper demonstrated that compounds like pectin or polygalacturaonic acid, which contain methoxyl groups can indeed function as precursors for the production of methane. The authors believe that to address this issue in greater detail, performing specific experiments focused on measuring emission rates of methane from living plants or plant parts is needed.

Published
2008
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12. Global atmospheric methane: budget, changes and dangers

Author

Dlugokencky, Edward J., Nisbet, Euan G., Fisher, Rebecca, and Lowry, David

Subjects
CH4, greenhouse gas mitigation, Research Groups and Centres\Earth Sciences\Ancient and Modern Earth Systems, biogeochemical cycles, GROWTH-RATE, GREENLAND, global methane budget, CARBON-DIOXIDE, VARIABILITY, Research Groups and Centres\Earth Sciences\Geochemistry, GAS, TERMINATION, isotope geochemistry, Faculty of Science\Earth Sciences, PLANTS, climate, EMISSIONS
Abstract

Contraceptive diaphragms offer a discreet method of pregnancy protection that women can use when needed with no side effects. Incorporating antiretroviral HIV microbicides into such devices may also provide protection against HIV infection. The paper gives a brief outline of the work being conducted by PATH, CONRAD and QUB on the development of a microbicide-releasing SILCS diaphragm. The design, engineering and manufacturing challenges that have been encountered will be discussed, as well as the potential impact such a device could have in the developing world. A factor of 2.5 increase in the global abundance of atmospheric methane (CH4) since 1750 contributes 0.5 Wm(-2) to total direct radiative forcing by long-lived greenhouse gases (2.77 Wm-2 in 2009), while its role in atmospheric chemistry adds another approximately 0.2Wm(-2) of indirect forcing. Since CH4 has a relatively short lifetime and it is very close to a steady state, reductions in its emissions would quickly benefit climate. Sensible emission mitigation strategies require quantitative understanding of CH4's budget of emissions and sinks. Atmospheric observations of CH4 abundance and its rate of increase, combined with an estimate of the CH4 lifetime, constrain total global CH4 emissions to between 500 and 600 Tg CH4 yr(-1). While total global emissions are constrained reasonably well, estimates of emissions by source sector vary by up to a factor of 2. Current observation networks are suitable to constrain emissions at large scales (e. g. global) but not at the regional to national scales necessary to verify emission reductions under emissions trading schemes. Improved constraints on the global CH4 budget and its break down of emissions by source sector and country will come from an enhanced observation network for CH4 abundance and its isotopic composition (delta C-13, delta D (D = H-2) and delta C-14). Isotopic measurements are a valuable tool in distinguishing among various sources that contribute emissions to an air parcel, once fractionation by loss processes is accounted for. Isotopic measurements are especially useful at regional scales where signals are larger. Reducing emissions from many anthropogenic source sectors is cost-effective, but these gains may be cancelled, in part, by increasing emissions related to economic development in many parts of the world. An observation network that can quantitatively assess these changing emissions, both positive and negative, is required, especially in the context of emissions trading schemes.

Published
2013

13. Methane soil-vegetation-atmosphere fluxes in tropical ecosystems

Author

Sanhueza, Eugenio

Subjects
Global Methane Budget, Methane from Vegetation, Methane in Tropical Ecosystems
Abstract

Recientemente, un sorpresivo descubrimiento mostró que, por un proceso no establecido, la vegetación emite metano. Esto podría tener serias implicaciones en química atmosférica, el clima, y las actividades de mitigación del cambio global. Para evaluar la magnitud de la vegetación tropical como fuente de CH4, se re-evalúan los resultados obtenidos en varios ecosistemas venezolanos. Los flujos a la atmósfera desde el sistema suelo-pasto en la sabana indican que los pastos producen CH4 a una velocidad de ~10ng·m-2·s-1. Además, la acumulación de CH4 dentro de la capa de mezcla nocturna en el Guri, lugar afectado por las emisiones de los ecosistemas de sabana y bosque, permite hacer una primera estimación del límite superior de la emisión de CH4 de la vegetación de bosque de

Published
2007

20. Methane budget from paddy fields in India

Author

Parashar, D. C., Mitra, A. P., Gupta, Prabhat K., Rai, J., Sharma, R. C., Singh, N., Kaula, S., Lal, G., Chaudhary, A., Ray, H. S., Das, S. N., Parida, K. M., Rao, S. B., Kanungo, S. P., Ramasami, T., Nair, B. U., Swamy, M., Singh, G., Gupta, S. K., Singh, A. R., Saikia, B. K., Barua, A. K. S., Pathak, M. G., Iyer, C. S. P., Gopalakrishnan, M., Sane, P. V., Singh, S. N., Banerjee, R., Sethunathan, N., Adhya, T. K., Rao, V. R., Palit, P., Saha, A. K., Purkait, N. N., Chaturvedi, G. S., Sen, S. P., Sen, M., Sarkar, B., Banik, A., Subbaraya, B. H., Lal, S., Venkatramani, S., and Sinha, S. K.

Published
1994

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