From The Independent, 5/7/06:
http://news.independent.co.uk/environment/article362549.ece
Ice-capped roof of world turns to desert
Scientists warn of ecological catastrophe across Asia as glaciers melt
and continent's great rivers dry up
By Geoffrey Lean
Global warming is rapidly melting the ice-bound roof of the world, and
turning it into desert, leading scientists have revealed.
The Chinese Academy of Sciences - the country's top scientific body -
has announced that the glaciers of the Tibetan plateau are vanishing
so fast that they will be reduced by 50 per cent every decade.
Each year enough water permanently melts from them to fill the entire
Yellow River.
They added that the vast environmental changes brought about by the
process will increase droughts and sandstorms over the rest of the
country, and devastate many of the world's greatest rivers, in what
experts warn will be an "ecological catastrophe".
The plateau, says the academy, has a staggering 46,298 glaciers,
covering almost 60,000 square miles.
At an average height of 13,000 feet above sea level, they make up the
largest area of ice outside the polar regions, nearly a sixth of the
world's total.
The glaciers have been receding over the past four decades, as the
world has gradually warmed up, but the process has now accelerated
alarmingly.
Average temperatures in Tibet have risen by 2 degrees Fahrenheit over
the past 20 years, causing the glaciers to shrink by 7 per cent a
year, which means that they will halve every 10 years.
Prof Dong Guangrong, speaking for the academy - after a study
analysing data from 680 weather stations scattered across the country
- said that the rising temperatures would thaw out the tundra of the
plateau, turning it into desert.
He added:
"The melting glaciers will ultimately trigger more droughts, expand
desertification and increase sand storms."
The water running off the plateau is increasing soil erosion and so
allowing the deserts to spread.
Sandstorms, blowing in from the degraded land, are already plaguing
the country.
So far this year, 13 of them have hit northern China, including
Beijing.
Three weeks ago one storm swept across an eighth of the vast country
and even reached Korea and Japan.
On the way, it dumped a mind-boggling 336,000 tons of dust on the
capital, causing dangerous air pollution.
The rising temperatures are also endangering the newly built world's
highest railway, which is due to go into operation this summer.
They threaten to melt the permafrost under the tracks of the £1.7bn
Tibetan railway, constructed to link the area with China's
northwestern Qinghai province.
Perhaps worst of all, the melting threatens to disrupt water supplies
over much of Asia.
Many of the continent's greatest rivers - including the Yangtze, the
Indus, the Ganges, the Brahmaputra, the Mekong and the Yellow River -
rise on the plateau.
In China alone, 300 million people depend on water from the glaciers
for their survival.
Yet the plateau is drying up, threatening to escalate an already dire
situation across the country.
Already 400 cities are short of water; in 100 of them - including
Beijing - the shortages are becoming critical.
Even hopes that the melting glaciers might provide a temporary
respite, by increasing the amount of water flowing off the plateau -
have been dashed.
For most of the water is evaporating before it reaches the people that
need it - again because of the rising temperatures brought by global
warning.
Yao Tandong, head of the academy's Qinghai-Tibet Plateau Research
Institute, summed it up.
"The full-scale glacier shrinkage in the plateau regions will
eventually lead to an ecological catastrophe," he said.
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Harry
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