“Global warming will defrost much more permafrost than we thought, a new study finds. Every 1°C (1.8°F) of additional warming would thaw one-quarter of the earth’s frozen tundra area — releasing staggering amounts of heat-trapping greenhouse gases (GHGs).” — Joe Romm
Sine 1910, the earth’s temperature has risen by more than 1C per the NOAA/GISS dataset. Per the above quote, we have already defrosted 25% of the permafrost. Do I read that right?
This means that model projections and the natural response of a century of carbon dioxide emissions (along with natural feedbacks) already have this permafrost “factor” included in them.
I guess the planet is a better buffer against climate change than we thought. That should be figured into those models.