Glaciers in China's bleak, rugged Qilian mountains are disappearing at a shocking rate as global warming brings unpredictable change and raises the prospect of crippling, long-term water shortages, scientists say.
The largest glacier in the 800-km (500-mile) mountain chain on the arid northeastern edge of the Tibetan plateau has retreated about 450 metres since the 1950s, when researchers set up China's first monitoring station to study it.
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The Tibetan plateau is known as the world's Third Pole for the amount of ice long locked in the high-altitude wilderness.
But since the 1950s, average temperatures have risen 1.5 Celsius in the area, Qin said, and with no sign of an end to warming, the outlook is grim for the 2,684 glaciers in the Qilian range.
Before: A satellite image shows the Laohugou No. 12 glacier in September, 2018. After: A satellite image shows the Laohugou No. 12 glacier in July, 2020.
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Across the mountains, glacier retreat was 50% faster in 1990-2010 than it was from 1956 to 1990, data from the China Academy of Sciences shows.
"When I first came here in 2005, the glacier was around that point there where the river bends," Qin said, pointing to where the rocky, treeless slopes of the Laohugou valley channel the winding river to lower ground.
The flow of water in a stream near the terminus of the Laohugou No. 12 runoff is about double what it was 60 years ago, Qin said.
Further downstream, near Dunhuang, once a major junction on the ancient Silk Road, water flowing out of the mountains has formed a lake in the desert for the first time in 300 years, state media reported.
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Global warming is also blamed for changes in the weather that have brought other unpredictable conditions.
Snowfall and rain has at times been much less than normal, so even though the melting glaciers have brought more runoff, farmers downstream can still face water shortages for their crops of onions and corn and for their animals.
Left: A bridge crosses the dried riverbed of the Shule river. Right: Mineral deposits lie in the midst of grass close to the dried bed of the Shule river.
Large sections of the Shule river, on the outskirts of Dunhuang, were either dry or reduced to murky pools, isolated in desert scrub when Reuters visited in September.
The new fluctuations also bring danger.
Left: Jianwei places a cauliflower on the back of his tricycle. Right: Jianwei takes a cauliflower from his mother Xie Xiaolin, 58.
For Gu Jianwei, 35, a vegetable farmer on the outskirts of the small city of Jiuquan, the changes in the weather have meant meagre water for his cauliflowers this year.
Gu said he had been able to water his crop just twice over two crucial summer months, holding up a small cauliflower head that he said was just a fraction of the normal weight.
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The evidence of the withering ice is all too clear for student researcher Jin Zizhen, out under a deep-blue sky checking his instruments in the glare of Laohugou No. 12.
“It's something I've been able to see with my own eyes."