Wenxin Zhang
Researcher
Cold-Season Methane Fluxes Simulated by GCP-CH4 Models
Author
Summary, in English
Cold-season methane (CH4) emissions may be poorly constrained in wetland models. We examined cold-season CH4 emissions simulated by 16 models participating in the Global Carbon Project model intercomparison and analyzed temporal and spatial patterns in simulation results using prescribed inundation data for 2000–2020. Estimated annual CH4 emissions from northern (>60°N) wetlands averaged 10.0 ± 5.5 Tg CH4 yr−1. While summer CH4 emissions were well simulated compared to in-situ flux measurement observations, the models underestimated CH4 during September to May relative to annual total (27 ± 9%, compared to 45% in observations) and substantially in the months with subzero air temperatures (5 ± 5%, compared to 27% in observations). Because of winter warming, nevertheless, the contribution of cold-season emissions was simulated to increase at 0.4 ± 0.8% decade−1. Different parameterizations of processes, for example, freezing–thawing and snow insulation, caused conspicuous variability among models, implying the necessity of model refinement.
Department/s
- Dept of Physical Geography and Ecosystem Science
- BECC: Biodiversity and Ecosystem services in a Changing Climate
- MERGE: ModElling the Regional and Global Earth system
Publishing year
2023
Language
English
Publication/Series
Geophysical Research Letters
Volume
50
Issue
14
Document type
Journal article
Publisher
American Geophysical Union (AGU)
Topic
- Physical Geography
Keywords
- cold-season emissions
- global warming
- methane budget
- model intercomparison
- wetland models
Status
Published
ISBN/ISSN/Other
- ISSN: 0094-8276