The environmental group Greenpeace has released photographs which it says dramatically illustrate the changes being wrought by global warming.

Greenpeace activists travelled to the coast of the Norwegian island of Svalbard, 600 kilometres (375 miles) north of the country's mainland, in the ship Rainbow Warrior.

The blame can be put squarely on human activity

Greenpeace

The have released a photograph they took there, along with one taken from almost exactly the same spot in 1918, to illustrate how much the Blomstrandbreen glacier has retreated.

"The blame can be put squarely on human activity," Greenpeace says in a statement on its website.

"Our addiction to fossil fuels releases millions of tonnes of greenhouse gases into the atmosphere, and this is what is causing temperatures to rise, and our future to melt before our eyes."

The contrast between the two photos is stark. In the 1918 photo, the horizon is dominated by a massive white glacier, the island's mountains almost hidden.

In the 2002 photo, the glacier is almost gone, leaving chunks of ice floating in the water and the mountains almost bare.

Rising waters

Greenpeace's photos echo the results of a recent study of Alaskan glaciers by US scientists that concluded the ice was melting even faster that previously thought.

The resulting melt waters, researchers said, could drive up global sea levels by 0.14 millimetres a year.

But Keith Echelmeyer, of the University of Alaska Fairbanks Geophysical Institute, who conducted that study, said it wasn't clear whether man-made global warming was the culprit.

Other factors, such as a reduction in snowfall, could also be to blame for the shrinking glaciers, he said last month.