Scientists just pointed out how the Earth itself could undermine a Paris climate agreement

With only days left, tensions are rising as countries race to resolve outstanding differences and forge an agreement that - hopefully - will set the planet on a path to avoiding the worst consequences of climate change.

The goal is an agreement that would set the world on a path to limit warming to below 2 degrees Celsius, or perhaps even 1.5 degrees Celsius, above pre-industrial levels. But at a news conference here at the Le Bourget conference centre, scientists pointed out a factor that could make hitting these targets quite a lot harder.

It's called permafrost.

http://www.nzherald.co.nz/world/news/article.cfm?c_id=2&objectid=11559222