Himalayan Global Warming Report

Global warming: Tibet's lofty glaciers melt away
Research by scientists shows that the ice fields on the roof of the world are disappearing faster than anyone thought.

from an article in "The Independent" by Clifford Coonan.

Dharamsala November 20th

The Qinghai-Tibet plateau is home to tens of thousands of glaciers, fields of ice at the roof of the world where Mount Everest and other Himalayan peaks look down on China and Nepal.

But the glaciers are melting faster than anyone thought, fresh research by Chinese scientists shows, as global warming speeds up the shrinkage of more than 80 per cent of the 46,377 glaciers on the lofty plateau.

Rising temperatures on the ice fields of Qinghai-Tibet and surrounding areas in the past 50 years are having a devastating effect on the environment, as receding glaciers translate into water shortages in China and huge swathes of south Asia.

China will soon have to add more deserts, droughts and sandstorms to its already lengthy list of pollution woes, while India and Nepal will have to deal with staggering environmental consequences, as the melting lakes of ice threaten essential natural resources for the large population centres at the foot of the mountain ranges.

About 47 per cent of China's glaciers are on the Qinghai-Tibet plateau in the Himalayas, where the Yangtze, Yellow, Brahmaputra, Mekong and Salween rivers all originate.

The rate of melting, estimated at some 7 per cent a year, has meant more water run-off from the plateau, which worsens soil erosion and leads to desertification.

It is an environmental nightmare for rivers such as the Yangtze, 20 per cent of which is fed by glaciers, while the Taklamakan Desert in north-west China could be flooded before later drying out, researchers say.

Research just released by China's leading scientific body, the Chinese Academy of Sciences, shows global warming is dealing a hammer blow to ice fields at some of the world's truly awesome mountain regions.

This week the United Nations warned that Tibet's glaciers could disappear within 100 years due to global warming.

"Almost all glaciers in China have already shown substantial melting," the UN Development Programme said in its 2006 Human Development Report. "This is a major threat to China's over-used and polluted water supplies. The 300 million farmers in China's arid western region are likely to see a decline in the volume of water flowing from the glaciers."

The melting glaciers have not led to more water flowing into China's dry north and west because much of the melted glacier water is evaporated before it reaches the country's drought-stricken farmers, again as a result of global warming.

In the past 40 years, glaciers across the Tibetan plateau that spills from China into South Asia have shrunk by 6,600 square kilometres, especially since the 1980s, the conservation group WWF said in a 2005 report. The glaciers now cover about 105,000 square kilometres, it said.

It is not just the glaciers of Tibet that are melting - 95 per cent of Alaska's glaciers are thinning, too. Global temperatures rose about 0.6C during the 20th century, and the consensus among scientists is that warming will continue as long as greenhouse gases, primarily carbon dioxide from the burning of fossil fuels, accumulate in the atmosphere.

China is the world's fastest-growing major economy, but it has only a quarter of the world's average water per person, and rampant economic growth has sharpened competition for water resources.

The Qinghai-Tibet plateau covers 2.5 million square kilometres - about a quarter of China's land surface - at an average altitude of four kilometres above sea level. The world's highest ice fields are a natural biological museum for the array of geological phenomena they contain.

The temperature has risen by 0.2C every 10 years, according to the Cold and Dry Zone Environment and Engineering Research Institute of the Chinese Academy of Sciences. The institute's scientists selected 5,000 glaciers in the region for study, using remote sensors and other methods for gathering geographical information, to monitor changes over the past 50 years, Liu Shiyin, one of the scientists taking part in the programme, told the Xinhua news agency.

The results were harrowing. Liu said only a small number of glaciers were expanding and about 82 per cent of the monitored glaciers had receded by 4.5 per cent in the past 50 years.

The rate of shrinkage in glaciers in the central and northwestern parts of the Qinghai-Tibet plateau was slightly slower, but it was noticeably faster in neighbouring areas.

Of 170 glaciers on the northwestern slope of the Qilian Mountains, a range of peaks in the northern province of Gansu formerly known as the Richthofen Range, 95 per cent had thinned by 4.9 metres each year on average. Only 10 glaciers had expanded during the period.

In the Tianshan Mountains in Xinjiang province, almost all the glaciers on the northern slopes, and 69 per cent of glaciers on the southern slopes, were dwindling.

In the Pamir Mountains of Central Asia, site of the 72km long Fedchenko Glacier, the world's longest ice field outside the polar region, the glacier acreage shrank by 10 per cent.

Glaciers on the northern slopes of the Kunlun Mountains, which stretch for 3,000km to form the border of Northern Tibet, are shrinking, as are the ice fields of the Himalayas, which are home to the world's tallest mountain, Mount Everest.

Global warming is causing China's highland glaciers, including those covering Everest, to shrink by an amount equivalent to all the water in the Yellow River every year.

Monitoring results show the flow of water in some rivers in north-west China's dry regions has been increasing, which was possibly a result of melting glaciers, Liu said.

Liu warned that if glaciers continued to melt at such a high rate, it "would impose serious impact on local production and the life of local people".

In Nepal, where temperatures rise an average of 0.06C per year, snow-fed rivers are declining, and water levels are getting lower on the wetlands of the Qinghai Plateau.

Melting icefields are expected to trigger more droughts in an already parched China, expand desertification and increase the frequency of sandstorms.

Han Yongxiang, a meteorologist, said average temperatures in Tibet have risen by nearly one degree centigrade since the 1980s, accelerating the melting of the glacier and frozen tundra of the Qinghai-Tibet plateau.

The desert is creeping right up to the edge of Beijing, despite the planting of millions of trees to stop the sand's onset.

Drought is a fact of life and sandstorms are getting worse every year in north China. A strong sandstorm swept across huge swathes of the country last month. One particularly virulent storm dumped 330,000 tonnes of dust on Beijing and had an impact as far away as South Korea and Japan.

It has been known for some time that the glaciers are melting. Last year, scientists said three quarters of the glacier in the south-east of Tibet, and the marine glacier along the Hengduan mountains, a series of parallel mountain ranges running through the provinces of Sichuan, Yunnan and Tibet, would fade away by 2100 if the temperature rises by 2.1C.

Earlier this year the Chinese ran a railway line across the plateau for the first time. China has ruled the remote mountainous region of Tibet since 1950.

Water shortages due to overuse affect 538 million people in northern China, where 42 per cent of the country's population is supplied by 14 per cent of the country's water, according to the UN report this week.

The report said that more than 70 per cent of the water in the Yellow, Huai and Hai rivers, which between them supply about half of China's population, is too polluted for human use. Half of China's rural poor live in the basin areas of these rivers.

China's deputy environment minister, Zhu Guangyao, said in June that dealing with pollution may cost the country as much as 10 per cent of its GDP, which was £1.2 trillion last year.

Not everyone agrees with the gloomy prognosis, and some scientists say that glaciers in the Himalayas have not drastically shrunk despite global warming and are unlikely to melt away in coming decades. Zhang Wenjing, an expert on glaciers, who also works at the Chinese Academy of Sciences, did not question global warming, however, he said it would take perhaps centuries to melt the dense ice packs that accumulate and creep down the Himalayas.

WWF believes glacier recession would first cause flooding, then, decades later, reduce the flows of major rivers such as the Ganges, Mekong and Yangtze. This would, WWF predicted, cause environmental problems for Nepal and parts of China and India as irrigation and hydropower suffered.

"The world faces an economic and development catastrophe if the rate of global warming isn't reduced," said Jennifer Morgan, the environmental group's climate change programme director. "They need to work together on reducing CO2 emissions, increasing the use of renewable energy and implementing energy efficiency measures."

The WWF ran a witness report by Ngawang Tenzing Jangpo, the Abbot of Tengboche monastery, the most revered monk in Khumbu, Nepal. "The temperature of the earth is rising. It is not natural," said the abbot, who has lived in Khumbu for over 30 years and witnessed floods from lakes bursting with glacial meltwater.

"The Sherpas of Khumbu may not know everything, but they are suffering the consequences of the people's greed. We mountain people should be careful and take precautions. If we don't save Khumbu today our fresh water will dry up and the problem will be impossible to solve in the future."

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2007-02-23 @ 02:17:20
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2007-02-24 @ 23:31:35

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