Ice shrinks, birds migrate early in warmer Arctic

By Alister Doyle, Environment Correspondent

INSIDE LONGYEARBYEN GLACIER, Norway (Reuters) - A Norwegian glacier has shrunk on an island 1,000 km (600 miles) from the North Pole, a usually frozen fjord is ice-free and snow bunting birds have migrated back early in possible signs of global warming.

At the tail end of the Arctic winter, polar sea ice extends less far south than normal around the Norwegian archipelago of Svalbard in what may be linked to a warming widely blamed on greenhouse gases released by burning fossil fuels.

"This glacier is dying," guide Eirik Karlsen said on a visit to a tunnel through the ice left by last summer's melt water cascading through the heart of the fast-retreating 3 km (2 mile) long glacier above the village of Longyearbyen.

The tunnel, big enough to walk along with ice stalactites hanging from the roof, snakes its way 15 meters below the surface of the Longyearbyen Glacier and shows that huge volumes of water flowed down towards the valley in 2006.

"In the end, the roof here will collapse," Karlsen told a group of visitors. "Hopefully not today." He said it was hard to blame the melt squarely on global warming. The glacier only formed 2,000 years ago when snowfall patterns changed.

Many residents say bone-chilling temperatures, blizzards and storms always vary drastically from year to year around the world's most northerly village, with or without global warming.

Still, U.N. climate experts says the Arctic is heating up faster than the rest of the planet because of global warming, threatening human livelihoods and species such as polar bears that depend on sea ice for hunting seals.

They say dark sea water and land, once exposed, soaks up more heat than ice and snow. Glaciers are in retreat in many parts of the world, from the Alps to the Himalayas, and could push up sea levels in coming decades and centuries.