Skip to main content
U.S. flag

An official website of the United States government

Strong atmospheric chemistry feedback to climate warming from Arctic methane emissions

January 1, 2011

The magnitude and feedbacks of future methane release from the Arctic region are unknown. Despite limited documentation of potential future releases associated with thawing permafrost and degassing methane hydrates, the large potential for future methane releases calls for improved understanding of the interaction of a changing climate with processes in the Arctic and chemical feedbacks in the atmosphere. Here we apply a “state of the art” atmospheric chemistry transport model to show that large emissions of CH4 would likely have an unexpectedly large impact on the chemical composition of the atmosphere and on radiative forcing (RF). The indirect contribution to RF of additional methane emission is particularly important. It is shown that if global methane emissions were to increase by factors of 2.5 and 5.2 above current emissions, the indirect contributions to RF would be about 250% and 400%, respectively, of the RF that can be attributed to directly emitted methane alone. Assuming several hypothetical scenarios of CH4 release associated with permafrost thaw, shallow marine hydrate degassing, and submarine landslides, we find a strong positive feedback on RF through atmospheric chemistry. In particular, the impact of CH4 is enhanced through increase of its lifetime, and of atmospheric abundances of ozone, stratospheric water vapor, and CO2 as a result of atmospheric chemical processes. Despite uncertainties in emission scenarios, our results provide a better understanding of the feedbacks in the atmospheric chemistry that would amplify climate warming.

Publication Year 2011
Title Strong atmospheric chemistry feedback to climate warming from Arctic methane emissions
DOI 10.1029/2010GB003845
Authors Ivar S.A. Isaksen, Michael Gauss, Gunnar Myhre, Katey M. Walter Anthony, Carolyn Ruppel
Publication Type Article
Publication Subtype Journal Article
Series Title Global Biogeochemical Cycles
Index ID 70035148
Record Source USGS Publications Warehouse
USGS Organization Woods Hole Coastal and Marine Science Center
Was this page helpful?