Monday, March 06, 2006

HIMALAYAS MELTING....

Himalayan melting risk surveyed
By Navin Singh
BBC News, Kathmandu

Weather station (WWF Nepal/Aarati Gurung)
The station will quantify climate changes in the area
A new weather station is expected to show the extent of warming in the Himalayas, one of the world's biggest deposits of ice and a key source of fresh water.

It has been installed on the longest Himalayan glacier, in the Everest region of Nepal.

There have been numerous reports of glacial retreats in the Himalayas over the years, but this weather station will be able to quantify changes to the local climate.

One part of it has been set up on the Nguzumpa Glacier to record solar radiation, relative humidity, air and soil temperature, wind speed and direction, and precipitation.

The other part has been placed in the river fed by the 35km-long glacier, to measure changes in flow caused by glacial melt.

Officials with Nepal's Department of Hydrology and Metrology will climb up the Cho Oyu Mountain to the Nguzumpa Glacier in March to collect data from the unmanned station.

"Once we get to see the figures in March, we will learn the extent of glacial retreat caused by global warming," said the department's chief glaciologist, Om Ratna Bajracharya.

Temperatures rising

Previous studies have shown temperatures in the Himalayas have been rising at a rate of 0.06C per year, fuelling fears that melting glaciers have been filling glacial lakes more rapidly.

There are 3,250 glaciers in the Nepalese Himalayas, and 2,315 of them contain glacial lakes that are increasing in size at varying rates.

"While we do know that there is a lot of glacier melting due to global warming, we still need to know the exact causes and dynamics of such melting," said Chandra Prasad Gurung, Nepal representative of the environmental group WWF which provided the weather station equipment.

"Therefore, having the weather station installed will help us understand more of the weather patterns and enable us to monitor the issue clearly."

Graph of glacial decline. Source: WGMS/Unep
Globally, glaciers have lost an average 6m in height in 20 years
Before the station, scientists either visited the glaciers themselves or studied satellite images to see any changes.

Most of the scientific reports have shown that glacial retreat and increases in lake size are occurring at a rapid rate.

Between 1970 and 1989, Japanese researchers discovered most glaciers in the Everest region had retreated 30-60m (100-200ft). To the west, in the Dhaulagiri region, field studies carried out before 1994 showed the same trend.

Nepal's most studied glacier in Tsorong Himal underwent a 10m (33ft) retreat between 1978 and 1989.

However, the Himalayan glacial system is not the only one under threat.

The World Glacier Monitoring Service, supported by the United Nations Environment Programme (Unep), collated records from across the globe and concluded that 30 major glaciers - assessed as being a representative global sample - had thinned by an average of 6m (20ft) between 1980 and 2001.

Flooding lakes ....

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