I don't mention much on climate change because it's covered heavily by people with much more expertise, but I thought I'd post this because it hits on one of my favorites themes: that processes like the retreat of Arctic sea ice are more complex than the media usually presents them to be. In this case, researchers doing the hard word of looking at sea ice in place discovered that initial melting created a "feedback" effect. "They found a layer of cold, salty water about 200 metres down that they suspect has come from the melting of first-year ice. That meltwater has forced the relatively warmer water to the surface, where it's speeding up the decay of more ice."
This planet is complicated - and NO process going on, whether ocurring by itself or with human help, is simple.