Gore's ice-cap claims disputed

Scientists stunned after ex-Vice-President says Arctic could be ice-free in five years

Al Gore yesterday faced an inconvenient truth of his own after a blunder over arctic ice levels.

Speaking at the Copenhagen climate change summit for the first time, Mr Gore quoted new research that showed the Arctic could be completely ice-free in five years.

"These figures are fresh. Some of the models suggest to Dr [Wieslav] Maslowski that there is a 75 per cent chance that the entire north polar ice cap, during the summer months, could be completely ice-free within five to seven years."

But it was also news to Dr Maslowski, who told the Times: "It's unclear to me how this figure was arrived at. I would never try to estimate likelihood at anything as exact as this."

The Times said Mr Gore's office later admitted that the 75 per cent figure was one used by Dr Maslowski as a "ballpark figure" several years ago in a conversation with Mr Gore.

Mr Gore's speech was criticised by members of the climate science community.

"This is an exaggeration that opens the science up to criticism from sceptics," Professor Jim Overland, a leading oceanographer at the US National Oceanic and Atmospheric Administration said.

"You really don't need to exaggerate the changes in the Arctic."

The reason for the criticism was because the inaccurate forecast suggested the ice cap would vanish much sooner than 2030, as was forecast by a US government agency eight months ago.

"It is hard to capture the astonishment that the experts in the science of ice felt when they saw this," Mr Gore, a former US Vice-President, told delegates and journalists.

Dr Maslowski, who works at the US Naval Postgraduate School in California, told the Times that his latest results give a six-year projection for the melting of 80 per cent of the ice, but he said he expects some ice to remain beyond 2020.

He added: "I was very explicit that we were talking about near-ice-free conditions and not completely ice-free conditions in the northern ocean. I would never try to estimate likelihood at anything as exact as this," he said.

"It's unclear to me how this figure was arrived at, based on the information I provided to Al Gore's office."

Other scientists told the Times that, even if quoted correctly, Dr Maslowski's six-year projection for near-ice-free conditions is at the extreme end of the scale. Most climate scientists agree that a 20 to 30-year timescale is more likely for the near-disappearance of sea ice.

"Maslowski's work is very well respected, but he's a bit out on a limb," said Professor Peter Wadhams, a specialist in ocean physics at the University of Cambridge.

Mr Gore's gaff has cast another shadow over the summit, after the controversy over hacked emails from the University of East Anglia's Climate Research Unit, which appeared to suggest that scientists had manipulated data to strengthen their argument that human activities were causing global warming.

- AP, HERALD STAFF