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They are a spectacular sight, made all the more enchanting because one has to trek thousands of meters up the mountains to behold them. But they are far less important as a treat to the eyes. Their real worth lies in the freshwater they store. They have given birth to civilizations and nurtured them for centuries, even millenniums. But today they are under threat because they are most vulnerable to global warming, for which humans have only themselves to blame.
Glaciers in the Himalayas and on the Qinghai-Tibet Plateau have nurtured two of the ancient and greatest civilizations of the world, and shaped their cultures and ways of life. Thanks to them, China and India have always been two great agricultural societies. Among the biggest rivers originating from these glaciers are the Yellow River known as the "mother river of China", the Ganges called the "soul of India", the Yangtze River, the Indus, the Mekong and the Yarlung Tsangpo. Today, these rivers are the source of life for not only people in China and India, but also those in Pakistan, Bangladesh, Myanmar, Laos, Cambodia, Vietnam and even Thailand.
But the "mother" is now weeping itself dry, and the "soul" is fast melting. Greenhouse gas emission and the resultant climate change perhaps pose a more imminent threat to glaciers (along with the ice sheets in the Arctic and the Antarctic), than any thing else. The dramatic change in weather patterns, too, can be linked to them.
But China's scientists, despite being ill-equipped, have always risen to the occasion to not only assess the damage caused by human activities, but also to find ways to save the precious glaciers.
Fifty years ago, Shi Yafeng led a small team of glacier scientists up the world's highest peaks. They didn't have the comfort of modern-day apparels and footwear then. They only had cotton jackets and plastic galoshes to fight the biting cold. And for equipment, they had the simplest of tools. The azure sky over the vast expanse of ice could be breathtaking, but the sun that makes it look so can be a torture to the eyes at those altitudes. They had to fight that too.
Today there is an institute in Lanzhou, capital of Northwest China's Gansu Province conducting research on glaciers. It is affiliated to the Chinese Academy of Sciences and enjoys worldwide fame. Liu Shiyin, one of the most respected scientists at the Cold and Arid Regions Environment and Engineering Research Institute, and his colleagues have access to more sophisticated equipment, but they still have to make do without proper mountaineering boots.
On their visits, they have found beds and cliffs of rocks that not long ago were covered by a thick sheet of ice. And they have seen water rush out faster even though the glaciers have retreated greatly. But they know the water flow will eventually turn into a trickle. Warmer weather may mean more water in the rivers initially, but in the long run the source will dry up and the result would be drought and severe weather change, says Liu.
Glaciers are the source of 75 percent of the earth's freshwater. A World Glacier Monitoring Service report published in January indicated that this decade glaciers have melted 1.6 and 3 times faster than in 1990s and 1980s. And the Zurich-based organization, too, blames climate change for that. China has the largest deposits of these sheets of ice after Canada, the United States and Russia. And it has felt the impact of the retreating lifelines as much as, if not more than, the rest of the world.
Take the country's most famous glacier, for example. Glacier No 1 in the Tianshan Mountain is the source of the Urumqi River. The sheet of ice in Northwest China's Xinjiang Uygur Autonomous Region retreated by 80 meters between 1962 and 1980, and another 60 meters between 1980 and 1992. It had shrunk to such an extent that in 1993 it split into two - and all because of global warming. Since the 1960s the eastern end of the glacier has retreated by more than 170 meters.
Glacier water plays a very important role in China's water system; it contributes the equivalent of the annual average flow of water from the Yellow River into the sea. Glacier water matters most to Gansu and Xinjiang, and parts of Gansu are already facing drought-like conditions. The Shiyang River, the lifeline of Minqin Oasis in the province, is fed mainly by Qilian Mountain glaciers. Since the 1990s, water from those glaciers has reduced greatly.
The Qingtu Lake in the oasis has disappeared altogether for lack of river water. The lake that used to be as deep as 40 meters in the 1950s, has today turned into a bed of shells where the Tengger and Badain Jaran deserts meet. Deserts are encroaching the oasis from the east, west and north, and moving at 8-10 meters a year. The oasis has been reduced to a one-km-wide, 10-km-long patch of land linked on its south with the Gansu Corridor.
More than 30,000 people have abandoned their homes there in the past decade. Today, all that can be seen of their houses are the roofs, which have somehow managed to stay above the fast depositing sand.
"If we look into the evolutionary history of oases along the rivers in China's inland west and also into the rise and fall of ancient cultures, we can see glaciers and their water have been the basis of regional social stability and economic development," says Liu.
The white sheet may be cold, but we need it for the warmth it provides - we tap its waters to generate electricity, we need it for our farmlands, and above all we need it to quench our thirst. Till we find a cheaper and more eco-friendly way to turn seawater into freshwater, till we can find a way to survive in warmer temperatures with more pollution and less power for our air-conditioners, we need the glaciers. That makes it the bounden duty of all humans to stop wasting water and cut greenhouse gas emission that aggravate the already serious climate condition.
(China Daily 07/24/2007 page12)
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