Ice melt, sea level rise and superstorms: Hansen on his magnum opus

Why ice sheets may melt faster than expected, and what that could mean for our near future

In this video Jim Hansen provides a “video abstract” of his latest — and longest — paper, Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 °C global warming could be dangerous, published this week after a lengthy period in review. He, and his stellar list of co-authors, have also provided an “abbrievated” version of the paper, which I strongly recommend you read.

My abstract is a bit shorter: fresh water from melting ice sheets in Greenland and Antarctica is beginning to change the way that heat moves around in the global ocean, setting up feedbacks that will melt the ice faster. This in turn will lead to much more rapid sea level rise than suggested in the recent IPCC report, and much bigger temperature contrasts between warm and cold oceans in the North Atlantic and around West Antarctica — which will drive the mid-latitude superstorms of the paper’s title.

Not a pretty prospect. And if you think it’s unlikely, consider this. There are already “cold blobs” in the North Atlantic and off West Antarctica, Atlantic storms are becoming much more vigorous , and there are hints of an acceleration in the rate of sea level rise.

Hansen has been right before. I hope, for all our sakes, that this time he’s not.

Riders on the storms

I listened with interest to Kevin Trenberth on the latest Climate Show describing how the increased water vapour in the atmosphere resulting from human-caused global warming is leading to greater extremes in weather events. It sent me back to take another look at the section in James Hansen’s book Storms of My Grandchildren where he explains the greatly increased strength of storms we can expect as the century unfolds, unless we leave most fossil carbon in the ground. I reviewed the book a while back on Hot Topic and thought it worth outlining more closely here, as an extension of my review, Hansen’s argument in the ten pages where he specifically addresses the storms of which the book’s title speaks.

Continue reading “Riders on the storms”