August 31, 2009

Swelling Glacial Lakes Threaten Nepalese Communities

In the small village of Dengboche at the foot of Nepal's Himalayas, residents have watched for years as a glacier-fed lake has continued to grow, an undeniable sign that the glacier is gradually melting.

According to an AFP report, elderly residents who have spent their entire lives in the village attest to the fact that the lake simply did not exist at all a mere 50 years ago.

The Imja Glacier, which looms ominously above Dengboche, has been retreating at a rate of roughly 230 feet per year say scientists.  The resulting lake formed by the melting run-off would potentially wreak havoc on the small town should it grow too large and burst through its banks.

And of the more than 2,300 glacial lakes in the country, officials say that at least twenty are in danger of bursting.

Nepal's International Center for Integrated Mountain Development (ICIMOD) has been observing the Himalaya's shrinking glaciers for some 30 years and says that a number of the country's glaciers have been on the decline for hundreds of years.

"Our studies of the past 30 years show that the temperatures are rising up to eight times faster that the global average," explained Samjwal Ratna Bajracharya, a glaciologists with the ICIMOD. 

"Melting is taking place higher and faster," he told AFP.  "The melting of glaciers and formation of glacier lakes is a key indicator of the temperature rise.  And lately we have seen massive ice melt."

The Imja lake is the second largest glacial lake in the country and is considered the most dangerous.

For a number of Nepalese residents, the threat of bursting lakes is more than an abstract contingency.

Native mountaineer Apa Sherpa who has scaled the face of Everest 19 times, says he lost his house and farm when the Dig Tsho glacial lake burst in 1985.

When Dig Tscho burst, seven people were killed, and bridges, houses and even a new hydropower plant were destroyed as the deluge rushed down the side of the mountain, sweeping away everything in its path.

"For me, climate change is personal," said Sherpa.  "There is probably no one who can relate to this issue in the way that I can."

Though the exact magnitude of the potential threat is not entirely understood, Nepal's Environmental Secretary Uday Raj Sharma has stated the bursting of Imja lake would be the equivalent of a "Nepalese tsunami."

Nepalese officials are requesting funds from international donors to help them manage the glacial lake threat.  Still, experts say there is no quick-and-easy fix for the problems. 

Native communities often refuse to leave their villages where they and generations of family have grown up, and attempts to drain the lakes are extremely expensive, dangerous and by no means foolproof.

In the 1990's the country collaborated with the Dutch government on a three-million-dollar project to release water from Tscho Rolpa, one of the largest and most potentially hazardous lakes in the eastern Himalayas.

A 70-yard long drain channel was carved out of the side of the lake, allowing it to drain-off into an uninhabited part of the countryside and significantly lowering the water level.

But such solutions are simply not feasible for all the lakes in the Nepal.

"We spent three million dollars without actually solving the problem," said ICIMOD's Bajracharya, who believes that early warning systems and awareness programs for at-risk communities would be a more practical investment.

A number of residents in the areas surrounding the glacial lakes, however, complain that the government is not doing enough to help their communities prepare.

"Everyone comes to us and tells us a Glacial Lake Outburst Flood will sweep through our villages.  But it doesn't do us any good," says Pasang Omo, a resident of Shomare in the eastern Himalayas at the foot of Imja lake.

"It's like telling someone they are sick but not giving them a cure."


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