NASA Scientist Says Icecaps Melting Faster Than Originally Thought
Posted on February 17, 2006
NASA scientist Jim Hansen is the Director of the NASA Goddard Institute for Space Studies in New York, and is President Bush's top climate modeller. But the White House doesn't like what he has to say and attempted to stop him from talking to the media about what the latest satellite studies show: the Greenland ice cap is melting far faster than scientists had feared - twice as much ice is going into the sea as it was five years ago. This could have a devastating effect on climate change as sea levels begin to rise. Here's what Hansen had to say:
"Yet, a few weeks ago, when I - a NASA climate scientist - tried to talk to the media about these issues following a lecture I had given calling for prompt reductions in the emission of greenhouse gases, the NASA public affairs team - staffed by political appointees from the Bush administration - tried to stop me doing so. I was not happy with that, and I ignored the restrictions. The first line of NASA's mission is to understand and protect the planet."The idea of gagging scientists is just absurd. Science is science: let's get the truth out there and see what we can do about it. It may very well be that New Orleans is just the first of many major cities that will have to be abandoned in the next decades, according to climatologists speaking on the BBC last night. One thing's for sure: it's probably better to rent a summer beach home than to buy one these days."This new satellite data is a remarkable advance. We are seeing for the first time the detailed behaviour of the ice streams that are draining the Greenland ice sheet. They show that Greenland seems to be losing at least 200 cubic kilometres of ice a year. It is different from even two years ago, when people still said the ice sheet was in balance. Hundreds of cubic kilometres sounds like a lot of ice. But this is just the beginning. Once a sheet starts to disintegrate, it can reach a tipping point beyond which break-up is explosively rapid. The issue is how close we are getting to that tipping point. The summer of 2005 broke all records for melting in Greenland. So we may be on the edge."
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How far can it go? The last time the world was three degrees warmer than today - which is what we expect later this century - sea levels were 25m higher. So that is what we can look forward to if we don't act soon. None of the current climate and ice models predict this. But I prefer the evidence from the Earth's history and my own eyes. I think sea-level rise is going to be the big issue soon, more even than warming itself.
It's hard to say what the world will be like if this happens. It would be another planet. You could imagine great armadas of icebergs breaking off Greenland and melting as they float south. And, of course, huge areas being flooded.
How long have we got? We have to stabilise emissions of carbon dioxide within a decade, or temperatures will warm by more than one degree. That will be warmer than it has been for half a million years, and many things could become unstoppable. If we are to stop that, we cannot wait for new technologies like capturing emissions from burning coal. We have to act with what we have. This decade, that means focusing on energy efficiency and renewable sources of energy that do not burn carbon. We don't have much time left.