Climate feedback from wetland methane emissions

The potential for wetland emissions to feedback on climate change has been previously hypothesised [ Houghton et al. , 2001]. We assess this hypothesis using an interactive wetlands scheme radiatively coupled to an integrated climate change effects model. The scheme predicts wetland area and methane (CH 4 ) emissions from soil temperature and water table depth, and is constrained by optimising its ability to reproduce the observed inter‐annual variability in atmospheric CH 4 . In transient climate change simulations the wetland response amplifies the total anthropogenic radiative forcing at 2100 by about 3.5–5%. The modelled increase in global CH 4 flux from wetland is comparable to the projected increase in anthropogenic CH 4 emissions over the 21st century under the IS92a scenario.