Carbon isotopic studies on methane in polar ice cores as a clue to past methane sources
Methane is recognised as an important greenhouse gas that contributes ~15 % to the current anthropogenic warming. With the help of isotopic analysis the contributions of different sources and sinks to the atmospheric burden can be estimated. Air enclosures in ice cores are the only direct paleoatmos...
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ftawi:oai:epic.awi.de:20997 2023-05-15T13:46:50+02:00 Carbon isotopic studies on methane in polar ice cores as a clue to past methane sources Behrens, Melanie Möller, Lars Fischer, Hubertus 2009 https://epic.awi.de/id/eprint/20997/ https://hdl.handle.net/10013/epic.33443 unknown Behrens, M. orcid:0000-0001-9275-4333 , Möller, L. and Fischer, H. (2009) Carbon isotopic studies on methane in polar ice cores as a clue to past methane sources , Jahrestagung der Arbeitsgemeinschaft Stabile Isotope e.V., 2009, Potsdam. . hdl:10013/epic.33443 EPIC3Jahrestagung der Arbeitsgemeinschaft Stabile Isotope e.V., 2009, Potsdam. Conference notRev 2009 ftawi 2021-12-24T15:33:38Z Methane is recognised as an important greenhouse gas that contributes ~15 % to the current anthropogenic warming. With the help of isotopic analysis the contributions of different sources and sinks to the atmospheric burden can be estimated. Air enclosures in ice cores are the only direct paleoatmospheric archive and allow an assessment of natural changes of methane in the past. Ice core reconstructions of atmospheric methane concentrations show significant increases for both glacial/interglacial transitions as well as for rapid warming events (Dansgaard/Oeschger events). Due to the different carbon isotopic signature of different methane sources high-precision measurements of delta13CH4 in ice cores supply clues about the global methane cycle.We developed a highly automated (continuous-flow) gas chromatography combustion isotope ratio mass spectrometry technique (GC/C/IRMS) for ice core samples of ~200 g. The methane is melt-extracted using a purge and trap method, then separated from the main air constituents, combusted and measured as CO2 by a conventional isotope ratio mass spectrometer. A CO2 working standard, a CH4 and two air reference gases are used to identify potential sources of isotope fractionation within the entire sample preparation process and to enhance the stability, reproducibility and accuracy of the system. We show the performance of our set-up and data from the Antarctic EDML ice core. Conference Object Antarc* Antarctic Dansgaard-Oeschger events ice core Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Antarctic The Antarctic |
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Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
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Methane is recognised as an important greenhouse gas that contributes ~15 % to the current anthropogenic warming. With the help of isotopic analysis the contributions of different sources and sinks to the atmospheric burden can be estimated. Air enclosures in ice cores are the only direct paleoatmospheric archive and allow an assessment of natural changes of methane in the past. Ice core reconstructions of atmospheric methane concentrations show significant increases for both glacial/interglacial transitions as well as for rapid warming events (Dansgaard/Oeschger events). Due to the different carbon isotopic signature of different methane sources high-precision measurements of delta13CH4 in ice cores supply clues about the global methane cycle.We developed a highly automated (continuous-flow) gas chromatography combustion isotope ratio mass spectrometry technique (GC/C/IRMS) for ice core samples of ~200 g. The methane is melt-extracted using a purge and trap method, then separated from the main air constituents, combusted and measured as CO2 by a conventional isotope ratio mass spectrometer. A CO2 working standard, a CH4 and two air reference gases are used to identify potential sources of isotope fractionation within the entire sample preparation process and to enhance the stability, reproducibility and accuracy of the system. We show the performance of our set-up and data from the Antarctic EDML ice core. |
format |
Conference Object |
author |
Behrens, Melanie Möller, Lars Fischer, Hubertus |
spellingShingle |
Behrens, Melanie Möller, Lars Fischer, Hubertus Carbon isotopic studies on methane in polar ice cores as a clue to past methane sources |
author_facet |
Behrens, Melanie Möller, Lars Fischer, Hubertus |
author_sort |
Behrens, Melanie |
title |
Carbon isotopic studies on methane in polar ice cores as a clue to past methane sources |
title_short |
Carbon isotopic studies on methane in polar ice cores as a clue to past methane sources |
title_full |
Carbon isotopic studies on methane in polar ice cores as a clue to past methane sources |
title_fullStr |
Carbon isotopic studies on methane in polar ice cores as a clue to past methane sources |
title_full_unstemmed |
Carbon isotopic studies on methane in polar ice cores as a clue to past methane sources |
title_sort |
carbon isotopic studies on methane in polar ice cores as a clue to past methane sources |
publishDate |
2009 |
url |
https://epic.awi.de/id/eprint/20997/ https://hdl.handle.net/10013/epic.33443 |
geographic |
Antarctic The Antarctic |
geographic_facet |
Antarctic The Antarctic |
genre |
Antarc* Antarctic Dansgaard-Oeschger events ice core |
genre_facet |
Antarc* Antarctic Dansgaard-Oeschger events ice core |
op_source |
EPIC3Jahrestagung der Arbeitsgemeinschaft Stabile Isotope e.V., 2009, Potsdam. |
op_relation |
Behrens, M. orcid:0000-0001-9275-4333 , Möller, L. and Fischer, H. (2009) Carbon isotopic studies on methane in polar ice cores as a clue to past methane sources , Jahrestagung der Arbeitsgemeinschaft Stabile Isotope e.V., 2009, Potsdam. . hdl:10013/epic.33443 |
_version_ |
1766245273606029312 |