Sea level rise of several meters now unstoppable
September 30th, 2009 by Jim JustThat’s the message experts delivered at a climate conference at Oxford University on Tuesday, September 29.
Stefan Rahmstorf, a scientist at Germany’s Potsdam Institute, said:
The crux of the sea level issue is that it starts very slowly but once it gets going it is practically unstoppable. There is no way I can see to stop this rise, even if we have gone to zero emissions.
According to Rahmstorf, the best outcome we can expect is that after temperatures stabilized, sea levels would only rise at a steady rate “for centuries to come” and not accelerate. His best guess is a one-meter rise this century – and up to five meters over the next 300 years. And there’s nothing we can do about it.
There is nothing we can do to stop this unless we manage to cool the planet. That would require extracting the carbon dioxide from the atmosphere. There is no way of doing this on the sufficient scale known today
The scientists warned that once the world’s ice starts to melt, the momentum may be unstoppable. Wageningen University’s Pier Vellinga said:
Once the ice is on the move, it’s like a tipping point which reinforces itself. Even if you reduce all the emissions in the world once this has started it may be unstoppable. I conclude that beyond 2 degrees global average temperature rise the probability of the Greenland ice sheet disintegrating is 50 percent or more. [That] will result in about 7 meters sea level rise, and the time frame is about 300-1,000 years.
Sea levels have risen about 20 centimeters in the past century – and the rate of rise is accelerating.