Lakes drain away to nothing as Siberian permafrost melts

A NEW study finds 125 large lakes in the Arctic vanished as temperatures rose over the past two decades. Many other lakes have shrunk.

The lakes once sat atop permanently frozen soil called permafrost. Other studies have shown permafrost around the world is melting, causing low-lying ground to slump and rock to fall from mountains.

“We think that climate warming is thawing the permafrost,” said lead researcher Laurence Smith of the University of California, Los Angeles. “It’s like pulling the plug out of a bathtub. There’s nothing to prevent lake water from percolating through the soil to aquifers below. From what we can tell from space, a lake is either just fine or it’s gone.”

The sudden draining could alter continental ecosystems, affecting birds and other wildlife that depend on the waterways, Mr Smith and his colleagues say.

Migratory birds count on the lakes during summer to feed their young.

Thousands of ponds, lakes and wetlands dot the north during summer.

“The loss of these lakes would be an ecological disaster,” Mr Smith said.

The researchers tracked changes across Siberia by comparing satellite imagery from 1972 to views from the late 1990s.

Meanwhile, Europe’s Alpine region is going through its warmest period in 1,300 years, a separate study has shown.

Study leader Reinhard Boehm, of Austria’s Central Institute for Meteorology and Geodynamics, said the current Alpine warm period began in the 1980s, noting a similar warming occurred in the 10th and 12th centuries. However, temperatures during those phases were “slightly under the temperatures we’ve experienced over the past 20 years”.

From 1850 to the 1970s, glaciers in the European Alps lost about 35% of their area. The melting then sped up, and now the 5,150 glaciers cover about 50% of the area they did in 1850.

By the end of this century, they could be nearly gone, according to a new computer model.

It indicates that if summer air temperatures rise by three degrees Celsius by the end of the century, 80% of the glacier cover will be gone. If summer temperatures were to increase by five degrees celsius, the Alps would become almost completely ice-free by 2100.

“Our study shows that under such scenarios, the majority of Alpine glaciers might disappear within the coming decades,” said glaciologist Michael Zemp, lead author of the study.

The scenario is similar elsewhere. Recent research at Glacier National Park in Montana found 26 named glaciers today, down from 150 in 1850.