Bayesian analysis of the glacial-interglacial methane increase constrained by stable isotopes and Earth System modelling
The observed rise in atmospheric methane (CH4) from 375 ppbv during the Last Glacial Maximum (LGM: 21,000 years ago) to 680 ppbv during the late preindustrial era is not well understood. Atmospheric chemistry considerations implicate an increase in CH4 sources, but process‐based estimates fail to re...
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2018
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Online Access: | https://hdl.handle.net/1983/477f0a21-b0c9-48e8-9d13-8e48cab29755 https://research-information.bris.ac.uk/en/publications/477f0a21-b0c9-48e8-9d13-8e48cab29755 https://doi.org/10.1002/2018GL077382 https://research-information.bris.ac.uk/ws/files/160543491/Hopcroft_et_al_2018_Geophysical_Research_Letters.pdf |
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ftubristolcris:oai:research-information.bris.ac.uk:publications/477f0a21-b0c9-48e8-9d13-8e48cab29755 2024-04-28T08:24:19+00:00 Bayesian analysis of the glacial-interglacial methane increase constrained by stable isotopes and Earth System modelling Hopcroft, Peter Valdes, Paul Kaplan, J 2018-05-15 application/pdf https://hdl.handle.net/1983/477f0a21-b0c9-48e8-9d13-8e48cab29755 https://research-information.bris.ac.uk/en/publications/477f0a21-b0c9-48e8-9d13-8e48cab29755 https://doi.org/10.1002/2018GL077382 https://research-information.bris.ac.uk/ws/files/160543491/Hopcroft_et_al_2018_Geophysical_Research_Letters.pdf eng eng https://research-information.bris.ac.uk/en/publications/477f0a21-b0c9-48e8-9d13-8e48cab29755 info:eu-repo/semantics/openAccess Hopcroft , P , Valdes , P & Kaplan , J 2018 , ' Bayesian analysis of the glacial-interglacial methane increase constrained by stable isotopes and Earth System modelling ' , Geophysical Research Letters . https://doi.org/10.1002/2018GL077382 wetlands Last Glacial Maximum methane 13CH4 greenhouse gas isotopic discrimination article 2018 ftubristolcris https://doi.org/10.1002/2018GL077382 2024-04-10T00:04:37Z The observed rise in atmospheric methane (CH4) from 375 ppbv during the Last Glacial Maximum (LGM: 21,000 years ago) to 680 ppbv during the late preindustrial era is not well understood. Atmospheric chemistry considerations implicate an increase in CH4 sources, but process‐based estimates fail to reproduce the required amplitude. CH4 stable isotopes provide complementary information that can help constrain the underlying causes of the increase. We combine Earth System model simulations of the late preindustrial and LGM CH4 cycles, including process‐based estimates of the isotopic discrimination of vegetation, in a box model of atmospheric CH4 and its isotopes. Using a Bayesian approach, we show how model‐based constraints and ice core observations may be combined in a consistent probabilistic framework. The resultant posterior distributions point to a strong reduction in wetland and other biogenic CH4 emissions during the LGM, with a modest increase in the geological source, or potentially natural or anthropogenic fires, accounting for the observed enrichment of δ13CH4. Article in Journal/Newspaper ice core University of Bristol: Bristol Research Geophysical Research Letters 45 8 3653 3663 |
institution |
Open Polar |
collection |
University of Bristol: Bristol Research |
op_collection_id |
ftubristolcris |
language |
English |
topic |
wetlands Last Glacial Maximum methane 13CH4 greenhouse gas isotopic discrimination |
spellingShingle |
wetlands Last Glacial Maximum methane 13CH4 greenhouse gas isotopic discrimination Hopcroft, Peter Valdes, Paul Kaplan, J Bayesian analysis of the glacial-interglacial methane increase constrained by stable isotopes and Earth System modelling |
topic_facet |
wetlands Last Glacial Maximum methane 13CH4 greenhouse gas isotopic discrimination |
description |
The observed rise in atmospheric methane (CH4) from 375 ppbv during the Last Glacial Maximum (LGM: 21,000 years ago) to 680 ppbv during the late preindustrial era is not well understood. Atmospheric chemistry considerations implicate an increase in CH4 sources, but process‐based estimates fail to reproduce the required amplitude. CH4 stable isotopes provide complementary information that can help constrain the underlying causes of the increase. We combine Earth System model simulations of the late preindustrial and LGM CH4 cycles, including process‐based estimates of the isotopic discrimination of vegetation, in a box model of atmospheric CH4 and its isotopes. Using a Bayesian approach, we show how model‐based constraints and ice core observations may be combined in a consistent probabilistic framework. The resultant posterior distributions point to a strong reduction in wetland and other biogenic CH4 emissions during the LGM, with a modest increase in the geological source, or potentially natural or anthropogenic fires, accounting for the observed enrichment of δ13CH4. |
format |
Article in Journal/Newspaper |
author |
Hopcroft, Peter Valdes, Paul Kaplan, J |
author_facet |
Hopcroft, Peter Valdes, Paul Kaplan, J |
author_sort |
Hopcroft, Peter |
title |
Bayesian analysis of the glacial-interglacial methane increase constrained by stable isotopes and Earth System modelling |
title_short |
Bayesian analysis of the glacial-interglacial methane increase constrained by stable isotopes and Earth System modelling |
title_full |
Bayesian analysis of the glacial-interglacial methane increase constrained by stable isotopes and Earth System modelling |
title_fullStr |
Bayesian analysis of the glacial-interglacial methane increase constrained by stable isotopes and Earth System modelling |
title_full_unstemmed |
Bayesian analysis of the glacial-interglacial methane increase constrained by stable isotopes and Earth System modelling |
title_sort |
bayesian analysis of the glacial-interglacial methane increase constrained by stable isotopes and earth system modelling |
publishDate |
2018 |
url |
https://hdl.handle.net/1983/477f0a21-b0c9-48e8-9d13-8e48cab29755 https://research-information.bris.ac.uk/en/publications/477f0a21-b0c9-48e8-9d13-8e48cab29755 https://doi.org/10.1002/2018GL077382 https://research-information.bris.ac.uk/ws/files/160543491/Hopcroft_et_al_2018_Geophysical_Research_Letters.pdf |
genre |
ice core |
genre_facet |
ice core |
op_source |
Hopcroft , P , Valdes , P & Kaplan , J 2018 , ' Bayesian analysis of the glacial-interglacial methane increase constrained by stable isotopes and Earth System modelling ' , Geophysical Research Letters . https://doi.org/10.1002/2018GL077382 |
op_relation |
https://research-information.bris.ac.uk/en/publications/477f0a21-b0c9-48e8-9d13-8e48cab29755 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1002/2018GL077382 |
container_title |
Geophysical Research Letters |
container_volume |
45 |
container_issue |
8 |
container_start_page |
3653 |
op_container_end_page |
3663 |
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1797584691786678272 |