The ice sheets covering the Arctic seas have thinned noticeably over the past seven years, most likely as a result of global warming, says a Norwegian explorer who has just skied alone across the top of the world.
Boerge Ousland, speaking after an 82-day trip in which he travelled 2100km from the northern tip of Russia to the North Pole and then down to Canada, said he had seen other evidence which hinted strongly at the effects of climate change.
The 38-year-old explorer, holder of four long-distance polar skiing records, measured the ice thickness as part of a study by the Norwegian Polar Institute. He made similar measurements on a trek from Russia to the North Pole in 1994.
"The ice toward the North Pole seems to be much thinner than normal and this made it much more broken so that the conditions were much more difficult than they had been in 1994 ... at around 87 degrees North it was up to a metre thinner," Mr Ousland said.
"I think that things are happening with [global] warming ... that the ice is getting thinner and there is less ice," he said.
