♦We use a process-based model (Terrestrial Ecosystem Model), which incorporates ypermafrost dynamics, to estimate the net methane exchanges of the northern high ylatitudes (north of 45oN) for current climate conditions and for future climate scenarios. yWe estimate that currently the region is a net source of methane to the atmosphere at 47 T yg yr-1, due largely to CH4 emissions from wet soils of the Arctic. We project that ythroughout the 21st century, the region will continue as a net source of methane. The ysources will range from 57 to 135 T g yr-1 depending on effects of permafrost dynamics yand warming climate on methanogenesis due to different climate scenarios. One potential ybias is that we have not yet coupled our biogeochemistry model with a General yCirculation Model to consider the feedback between methane emissions and climate. yAnother uncertainty also exists due to the limited knowledge about how wetland ydistributions might change, and such changes could affect methane emissions in the yfuture.