Sea and land ice at both poles crept toward alarming seasonal lows this week. Freak heat waves in the high Arctic have kept ice from forming at the usual winter rate, and now summer down under is taking its toll on the world’s largest ice sheets:
Sea ice in the Antarctic is at its lowest level since records began while the Arctic is on track for another historic new low. According to figures from the US National Snow & Ice Data Centre (NSIDC), sea ice in the Antarctic covered just 2.3 million square kilometres on 12 February — compared to the average between 1981 and 2010 of more than three million on that day.
Warmer temperatures do more than directly melt the ice and feed runaway polar amplification of global warming. More energy in the surface troposphere, the part of the atmosphere we and just about everything else lives in, means more wind, faster evaporations and sublimation, leading to bigger weather systems and storms. The precise activity that further stirs and helps break up icy formations, especially tongues and large shelves of ice floating on top of polar seas.
The Arctic as defined by a permanent ice-cap is almost certainly doomed in our lifetime. The immediate future of Antarctica in a rapidly warming world is not as well understood, but if steps aren't taken soon to significantly curb global greenhouse gas emissions, it will not survive in its current, pristine form.