From Peter Sinclair:
One of the most feared of climate change "feedbacks" is the potential release of greenhouse gases by melting arctic permafrost soils. New research indicates a critical threshold of that feedback effect could be closer than we once thought.
More confirmation of "background" science. (The denialists are out in force in the comments section) "In prehistory, CO2 and warming went in lock-step" http://phys.org/news/2013-02-prehistory-co2-lock-step.html
Add permafrost thawing and we have a pretty convincing recipe for disaster.
They don't know about the carbon cycle
The reality of all of that previously tied up carbon freed into the atmosphere scares the crap out of me. It should scare them too.