THE world's largest temperate glacier is melting faster than ever before, according to Greenpeace.

Photographic evidence produced by a Greenpeace expedition to the Western Arctic shows a vast meltwater lake around the Bering Glacier in Alaska: and thousands of icebergs breaking away from the main ice sheet. Scientists now believe the 2,000 square-mile glacier is retreating at a world record rate of more than half a mile each year.

The development supports the conclusion of the Intergovernmental Panel on Climate Change that the Earth is about to experience a period of global warming unequalled in 10,000 years. The news will greet delegates from 150 countries as they gather this week to restart talks on greenhouse gas reductions.

Governments meet in Bonn to resume discussions aimed at agreeing legally binding targets for greenhouse gases. The talks are due to be completed in time for signing at the third Conference of the Parties to the Climate Convention in Kyoto, Japan, in December.

The Greenpeace expedition, in collaboration with scientists from the United States geological survey, has uncovered new evidence of rising temperatures around the Bering Glacier, which stretches 120 miles from the St Elias Mountains down to the Gulf of Alaska, east of Anchorage. The region has warmed at the rate of almost 1C per decade for the last 30 years - several times the average global rate.

"The ice loss we're seeing from the Alaskan glaciers is really shocking," said expedition leader Steve Sawyer on board the Greenpeace vessel Arctic Sunrise. "This is part of a massive worldwide loss of glaciers.

"Unless we do something to decrease our burning of greenhouse fuels like oil, we will have to redraw the maps of our major mountains in Alaska, the Andes and the Alps. We may as well Tippex out the glaciers now unless we're serious about stopping the warming."

The IPCC concluded last year that "thinning of glaciers since the mid 19th century has been obvious and pervasive in many parts of the world" and said it had contributed up to 2in of this century's global sea rise of approximately 10in.

If present trends continue, it is believed sea levels could rise by several feet over the next couple of centuries. This may set off a secondary threat since the covering of cold land by a relatively warmer ocean will accelerate the decay of organic matter, producing vast quantities of methane, a far more powerful greenhouse gas than carbon dioxide.

Greenpeace is using the Arctic expedition as part of its campaign to halt further oil exploration, particularly in the Atlantic north and west of Scotland. "We cannot afford to burn the oil that we've already foumd," said Mr Sawyer. "It's completely irresponsible to spend billions of pounds exploring for any new oil."

Last week, the group applied at the High Court in London for a judicial review of the Government's award of further exploration licences for the North Atlantic. Scheduling a hearing for later in the year, Mr Justice Tucker, presiding, said: "This is a case of considerable importance, high sensitivity and national interest for all parties concerned. This is a matter of some urgency."