Scientists have been warning that glaciers are receding and lakes are drying up in Latin American America because of global warming.
Even while some sections are adamantly skeptical about such assertions, Chilean scientists have reported the disappearance of a whole lake in the south of the country.
AdvertisementThe lake, some 20,000 square metres in area, in the Bernardo O'Higgins National Park in Patagonia, Chile, was last seen in March.
By May, all that was left was a crater and a few strands of floating ice. A river running from it had also reduced to a trickle, according to the park rangers of the southernmost region of Magallanes.
"The lake had simply disappeared,' said Juan Jose Romero, regional director of Chile's National Forest Service. "No one knows what happened.'
'This is the first time our park rangers have recorded anything like this. However, we are not specialists, and we prefer not to speculate about the cause at this point, said Romero.
Experts now say melting glaciers put pressure on an ice wall that acted as a dam, causing it to give way.
After flying over the lake on Tuesday, scientists said they were able to draw preliminary conclusions that point to climate change as the leading culprit for the lake's disappearance.
They suggested the melting of nearby glaciers raised the lake's level to the point where the increased water pressure caused part of a glacier acting as a dam to give way.
Water in the lake flowed out of the breach, into a nearby fiord and then to the sea, said Andres Rivera, a glaciologist with Chile's Centre of Scientific Studies.
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 pointed out.
Chilean glaciologist Gino Casassa, one of the 63 experts who participated in the second UN report on global warming, had observed in May itself possibly the lake disappeared due to a relatively common glacial phenomenon: a Glacial Lake Outburst Flood (GLOF). A GLOF is a sudden increase in a lake's volume due to one of various possible causes, including a volcanic eruption, an earthquake, an avalanche, or a portion of a glacier falling into the lake.
Casassa said that the GLOF broke open a tunnel of ice below the lake, which drained the water to the ocean. 'In this zone in particular... we have evidence that, in general, the lakes are filling up as the glaciers melt,' Casassa added. Global warming is most likely responsible for this process, as well as for the increase in GLOFs.