Global warming 'made lake vanish'

Park rangers who patrolled the area in the Magallanes region in March reported that the two-hectare (five-acre) glacial lake was its normal size.

But two months later they found a huge dry crater and stranded chunks of ice that previously floated on the water.

Experts now say melting glaciers put pressure on an ice wall that acted as a dam, causing it to give way.

Water in the lake flowed out of the breach into a nearby fjord and then out to the sea, said Andres Rivera, a glaciologist with Chile's Centre of Scientific Studies.

Melting ice

Mr Rivera flew on Monday in a navy airplane to take hundreds of photographs of the site, which is some 2,000km (1,250 miles) south of the capital, Santiago.

"On one side of the Bernardo glacier one can see a large hole or gap, and we believe that's where the water flowed through," Mr Rivera said in a navy communique.

"This confirms that glaciers in the region are retreating and getting thinner."

He noted that the lake now appears to be filling up again, probably because of the melting of slabs of ice left on the lake bed.

The advance and retreat of glaciers is part of the normal dynamic of the Patagonian region but climate change was distorting the process, Mr Rivera said.

"This would not be happening if the temperature had not increased," he added.

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