Is this related to those mysterious giant craters that suddenly appeared in Siberia? I remember underground gasses released by the thawing permafrost being discussed as a possible cause for them. That video of Peter Wadhams seems quite alarming. The further along we go without serious action or leadership, the harder it will be to adapt to these changes. I'm just a layman, but I think four degrees of climate change, and it's associated affects, will put significant pressure on many aspects of human society, not to mention the wider biosphere.
It's related to the giant craters as they are both massive methane expulsions caused by warming in that region. This is a terribly bad event for us (not the planet, us) because it means that Climate Change has reached a stage where it is effecting the arctic. There is an unbelievable amount of methane stored in the arctic. And since methane is like an uber greenhouse gas, we are going to see the effects on an even more drastic scale. As one Arctic Climatologist said: "We're Fucked"