Improved ELMv1-ECA simulations of zero-curtain periods and cold-season CH4 and CO2 emissions at Alaskan Arctic tundra sites
Field measurements have shown that cold-season methane (CH4) and carbon dioxide (CO2) emissions contribute a substantial portion to the annual net carbon emissions in permafrost regions. However, most earth system land models do not accurately reproduce cold-season CH4 and CO2 emissions, especially...
Published in: | The Cryosphere |
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Copernicus Publications
2021
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Online Access: | https://doi.org/10.5194/tc-15-5281-2021 https://tc.copernicus.org/articles/15/5281/2021/tc-15-5281-2021.pdf https://doaj.org/article/df538f9e88824470b5af2f4a6e5dc673 |
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fttriple:oai:gotriple.eu:oai:doaj.org/article:df538f9e88824470b5af2f4a6e5dc673 2023-05-15T14:56:47+02:00 Improved ELMv1-ECA simulations of zero-curtain periods and cold-season CH4 and CO2 emissions at Alaskan Arctic tundra sites J. Tao Q. Zhu W. J. Riley R. B. Neumann 2021-11-01 https://doi.org/10.5194/tc-15-5281-2021 https://tc.copernicus.org/articles/15/5281/2021/tc-15-5281-2021.pdf https://doaj.org/article/df538f9e88824470b5af2f4a6e5dc673 en eng Copernicus Publications doi:10.5194/tc-15-5281-2021 1994-0416 1994-0424 https://tc.copernicus.org/articles/15/5281/2021/tc-15-5281-2021.pdf https://doaj.org/article/df538f9e88824470b5af2f4a6e5dc673 undefined The Cryosphere, Vol 15, Pp 5281-5307 (2021) envir geo Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2021 fttriple https://doi.org/10.5194/tc-15-5281-2021 2023-01-22T17:58:27Z Field measurements have shown that cold-season methane (CH4) and carbon dioxide (CO2) emissions contribute a substantial portion to the annual net carbon emissions in permafrost regions. However, most earth system land models do not accurately reproduce cold-season CH4 and CO2 emissions, especially over the shoulder (i.e., thawing and freezing) seasons. Here we use the Energy Exascale Earth System Model (E3SM) land model version 1 (ELMv1-ECA) to tackle this challenge and fill the knowledge gap of how cold-season CH4 and CO2 emissions contribute to the annual totals at Alaska Arctic tundra sites. Specifically, we improved the ELMv1-ECA soil water phase-change scheme, environmental controls on microbial activity, and the methane module. Results demonstrate that both soil temperature and the duration of zero-curtain periods (i.e., the fall period when soil temperatures linger around 0 ∘C) simulated by the updated ELMv1-ECA were greatly improved; e.g., the mean absolute error (MAE) in zero-curtain durations at 12 cm depth was reduced by 62 % on average. Furthermore, the MAEs of simulated cold-season carbon emissions at three tundra sites were improved by 72 % and 70 % on average for CH4 and CO2, respectively. Overall, CH4 emitted during the early cold season (September and October), which often includes most of the zero-curtain period in Arctic tundra, accounted for more than 50 % of the total emissions throughout the entire cold season (September to May) in the model, compared with around 49.4 % (43 %–58 %) in observations. From 1950 to 2017, both CO2 emissions during the zero-curtain period and during the entire cold season showed increasing trends, for example, of 0.17 and 0.36 gC m−2 yr−1 at Atqasuk. This study highlights the importance of zero-curtain periods in facilitating cold-season CH4 and CO2 emissions from tundra ecosystems. Article in Journal/Newspaper Arctic permafrost The Cryosphere Tundra Alaska Unknown Arctic The Cryosphere 15 12 5281 5307 |
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English |
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envir geo J. Tao Q. Zhu W. J. Riley R. B. Neumann Improved ELMv1-ECA simulations of zero-curtain periods and cold-season CH4 and CO2 emissions at Alaskan Arctic tundra sites |
topic_facet |
envir geo |
description |
Field measurements have shown that cold-season methane (CH4) and carbon dioxide (CO2) emissions contribute a substantial portion to the annual net carbon emissions in permafrost regions. However, most earth system land models do not accurately reproduce cold-season CH4 and CO2 emissions, especially over the shoulder (i.e., thawing and freezing) seasons. Here we use the Energy Exascale Earth System Model (E3SM) land model version 1 (ELMv1-ECA) to tackle this challenge and fill the knowledge gap of how cold-season CH4 and CO2 emissions contribute to the annual totals at Alaska Arctic tundra sites. Specifically, we improved the ELMv1-ECA soil water phase-change scheme, environmental controls on microbial activity, and the methane module. Results demonstrate that both soil temperature and the duration of zero-curtain periods (i.e., the fall period when soil temperatures linger around 0 ∘C) simulated by the updated ELMv1-ECA were greatly improved; e.g., the mean absolute error (MAE) in zero-curtain durations at 12 cm depth was reduced by 62 % on average. Furthermore, the MAEs of simulated cold-season carbon emissions at three tundra sites were improved by 72 % and 70 % on average for CH4 and CO2, respectively. Overall, CH4 emitted during the early cold season (September and October), which often includes most of the zero-curtain period in Arctic tundra, accounted for more than 50 % of the total emissions throughout the entire cold season (September to May) in the model, compared with around 49.4 % (43 %–58 %) in observations. From 1950 to 2017, both CO2 emissions during the zero-curtain period and during the entire cold season showed increasing trends, for example, of 0.17 and 0.36 gC m−2 yr−1 at Atqasuk. This study highlights the importance of zero-curtain periods in facilitating cold-season CH4 and CO2 emissions from tundra ecosystems. |
format |
Article in Journal/Newspaper |
author |
J. Tao Q. Zhu W. J. Riley R. B. Neumann |
author_facet |
J. Tao Q. Zhu W. J. Riley R. B. Neumann |
author_sort |
J. Tao |
title |
Improved ELMv1-ECA simulations of zero-curtain periods and cold-season CH4 and CO2 emissions at Alaskan Arctic tundra sites |
title_short |
Improved ELMv1-ECA simulations of zero-curtain periods and cold-season CH4 and CO2 emissions at Alaskan Arctic tundra sites |
title_full |
Improved ELMv1-ECA simulations of zero-curtain periods and cold-season CH4 and CO2 emissions at Alaskan Arctic tundra sites |
title_fullStr |
Improved ELMv1-ECA simulations of zero-curtain periods and cold-season CH4 and CO2 emissions at Alaskan Arctic tundra sites |
title_full_unstemmed |
Improved ELMv1-ECA simulations of zero-curtain periods and cold-season CH4 and CO2 emissions at Alaskan Arctic tundra sites |
title_sort |
improved elmv1-eca simulations of zero-curtain periods and cold-season ch4 and co2 emissions at alaskan arctic tundra sites |
publisher |
Copernicus Publications |
publishDate |
2021 |
url |
https://doi.org/10.5194/tc-15-5281-2021 https://tc.copernicus.org/articles/15/5281/2021/tc-15-5281-2021.pdf https://doaj.org/article/df538f9e88824470b5af2f4a6e5dc673 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic permafrost The Cryosphere Tundra Alaska |
genre_facet |
Arctic permafrost The Cryosphere Tundra Alaska |
op_source |
The Cryosphere, Vol 15, Pp 5281-5307 (2021) |
op_relation |
doi:10.5194/tc-15-5281-2021 1994-0416 1994-0424 https://tc.copernicus.org/articles/15/5281/2021/tc-15-5281-2021.pdf https://doaj.org/article/df538f9e88824470b5af2f4a6e5dc673 |
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undefined |
op_doi |
https://doi.org/10.5194/tc-15-5281-2021 |
container_title |
The Cryosphere |
container_volume |
15 |
container_issue |
12 |
container_start_page |
5281 |
op_container_end_page |
5307 |
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1766328851123666944 |