期刊名称:Journal of Integrative Environmental Sciences
印刷版ISSN:1943-815X
电子版ISSN:1943-8168
出版年度:2010
卷号:7
页码:119-124
DOI:10.1080/19438151003621375
语种:English
出版社:Taylor & Francis
摘要:The interglacial–glacial decrease in atmospheric methane concentration is often attributed to a strong decline in the wetland source. This seems consistent with the extreme coldness and vastly expanded ice sheets. Here we analyse coupled model simulations for the last glacial maximum from the Paleoclimate Modelling Intercomparison Project, using simple relations to estimate wetland characteristics from the simulated climate and vegetation. It is found that boreal wetlands shift southward in all simulations, which is instrumental in maintaining the boreal wetland source at a significant level. The mean emission temperature over boreal wetlands drops by only a few degrees, despite the strong overall cooling. The temperature effect on the glacial decline in the methane flux is therefore moderate, while reduced plant productivity contributes equally to the total reduction. Moisture effects play a role on the local scale only, while averaging out globally.