The permafrost carbon feedback is an
amplification of surface warming due to the thaw
of organic material currently frozen in permafrost,
which will then decay and release CO2 and
methane into the atmosphere.
The next IPCC report, IPCC5 hasn't been written, but it's already obsolete. It will not model the effects of the melting of Arctic permafrost which contains 1,700 gigatons of carbon, twice as much carbon as today's atmosphere. Moreover, permafrost melting produces copious amounts of methane, a gas with many times the greenhouse effectiveness of CO2. Once the permafrost starts melting rapidly it is a potentially self-sustaining feedback loop even if human emissions cease. Once firmly established, this feedback will cause the 2° Celsius limit to avoid catastrophic climate change to be exceeded. In the year 2100, 40% of total CO2 emissions are predicted to come from permafrost melting according to a report released today by the UN.
These emissions from permafrost are predicted to continue for over a hundred years even if all human sourced CO2 emissions stop. However, none of these effects have been considered by IPCC reports to date and they won't be in the next one. The IPCC is giving policy makers guidance that severely underestimates the speed and intensity of climate change. The need for action now at Doha is far more urgent than politicians and policy makers realize. Permafrost melting is not the only important feedback loop that the IPCC has ignored (e.g. Siberian shelf methane production). These serious IPCC underestimates of feedback effects have allowed economists and policy makers to miscalculate, far to the low side, the costs and consequences of inaction and delay.
Projections of emissions from thawing permafrost
The lead author of the report, Kevin Shafer, spoke at Doha today.
CO2 and methane emissions from thawing permafrost can continue for decades or even centuries, as seen in this plot of estimated annual permafrost emissions in CO2 equivalent for the IPCC A1B scenario. In this scenario, anthropogenic emissions stop in 2100, but permafrost CO2 and methane emissions continue well past 2200 (Schaefer et al. 2011)
“Thawing permafrost in turn can impact global climate,” said Schaefer, a researcher at the U.S. National Snow and Ice Data Center in Boulder, Colorado. “It will begin to trigger what is called the permafrost-carbon feedback. Once the feedback starts, it’s irreversible because once you take that organic matter out, it’s impossible to put it back. It’ll also persist for centuries.”
Schaefer, speaking in Doha, said thawing permafrost could account for 39 percent of total global greenhouse gas emissions by 2100. Because emissions from permafrost aren’t included in current projections of future emissions, the world risks overshooting its 2-degree warming target, he said.
Permafrost melting destroyed a house in coastal Alaska.
Methane and CO2 emissions from melting permafrost are rising in the Arctic. Severe damage to land and property has already been observed in affected areas. Rapid acceleration of permafrost melting is expected over the next few decades, amplifying the speed and intensity of Arctic warming and global climate change.
Climate change is the real crisis congress and the president need to address, not a tempest in a teapot like the "fiscal cliff". It's a real threat to our grandchildren unlike the federal budget deficit. Over the past decade America has been hit by a record number of weather disasters at a record cost. The damage is only going to get worse, far worse, if we don't act quickly and decisively to cut greenhouse gas emissions.