For the last couple of years there's been some unusual weather behavior in the Arctic. It appears to be some sort of phase change, an abrupt alteration in the usual winter patterns, over and above the general temperature increase. The rise in temperature is what you'd expect from climate change, but these other changes seem superimposed on the general warming. It may be that the system is plateauing, adjusting to the new regime--a kind of interim stability condition. Then again, maybe its something more profound, a turning point of sorts, a hint of things to come--a calm before the storm.

I can't bear it out with any specific statistics or data, but my feeling is that the weather machine is now operating in a different mode. Whether its stable, even for the short term, or not its too early to tell yet.

The Antarctic seems to be changing too. Ice extent is much more stable there than in the Arctic because the Southern Ocean is a much more effective heat sink-it tends to dampen out the discrete events and trends The Southern sea ice has been remarkably constant while the North has undergone a catastrophic decline. But for the last few years, there has been a slight but measurable drop in the summer sea ice, less than in the North, but undeniable nonetheless.

Hopefully, the world heat engine is settling into a new state, one more capable of handling the constantly increasing temperature. I hope so. Maybe the change will be gradual when it comes, and it won't be the abrupt runaway cascade we fear.

I can't prove any of this, of course. I'm not even convinced myself, but I've been studying this for a while now and I'd like to think I'm developing a sort of intuition about it.