When I look at the numbers involved, I sometimes wonder whether concerns about climate change adaptation in northern community are missing the main point. As discussed before, the Arctic permafrost contains 36 trillion tonnes (teratonnes) of carbon dioxide equivalent. By comparison, annual human emissions are in the neighbourhood of 29 billion tonnes (gigatonnes) of CO2 equivalent. That means that the permafrost as a whole contains as much greenhouse gas as over 1,200 years of human emissions at the present rate. Thought about another way, that means that annual melting of 0.08% of the permafrost would have as much impact on climate change as every vehicle, power plant, farm, and burned forest around the world.
It is as though the permafrost is a frozen block of fuel that we are holding a match to. If it starts generating enough heat to melt on its own accord, we will be in for a truly wild ride. The loss of seasonal road access for northern communities may end up being the least significant problem associated with melting permafrost.