Improved ELMv1-ECA simulations of zero-curtain periods and cold-season CH₄ and CO₂ emissions at Alaskan Arctic tundra sites

Abstract 4) 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 - 1 4 and CO2 emissions from tundra ecosystems.

Angaben zum Objekt

• Standort: Deutsche Nationalbibliothek Frankfurt am Main
• Umfang: Online-Ressource
• Sprache: Englisch

Verweise und Beziehungen

• Erschienen in: Improved ELMv1-ECA simulations of zero-curtain periods and cold-season CH₄ and CO₂ emissions at Alaskan Arctic tundra sites ; volume:15 ; number:12 ; year:2021 ; pages:5281-5307 ; extent:27 ; The Cryosphere ; 15, Heft 12 (2021), 5281-5307 (gesamt 27)

Beteiligte, Orts- und Zeitangaben

• Urheber: Tao, Jing ; Zhu, Qing ; Riley, William J. ; Neumann, Rebecca B.

Weitere Informationen

• DOI: 10.5194/tc-15-5281-2021
• URN: urn:nbn:de:101:1-2021120204182797008560
• Rechteinformation: Open Access; Der Zugriff auf das Objekt ist unbeschränkt möglich.
• Letzte Aktualisierung: 15.08.2025, 07:26 MESZ