Lhasa (Tibet), Sep 8: The massive flash flood that struck the Tibet-Nepal border on August 26 has put China’s numerous hydropower projects in the region, including the mega dam on the Brahmaputra River, under renewed scrutiny, as Chinese experts said global warming and accelerating glacier retreat may have contributed to the recent gigantic mudslide.
The disaster was likely the result of a combination of factors, including rising temperatures and accelerated glacier melt, glacier retreat, local geological and geomorphological conditions and broader climatic influences, according to Chinese climate experts.
“According to our monitoring, we can see the short-time rain days, or the imbalance of the rain pattern and the rising of the temperature in Tibet,” said Sun Xiaoguang, head of the Meteorological Observatory of the Tibet Autonomous Region.
The Tibet region may be affected by the climate change crisis, he said.
“As far as I know, and according to the reports published by the Meteorological Observatory of China, I think there are… there will be more and more extreme weather, or extreme weather incidents in China that was impact [of] or affected by the climate change,” he said, talking to PTI while on his way to the flash flood-hit area close to the Tibet-Nepal border on Sunday.
The August 26 disaster was triggered by an ice-rock avalanche near the Nepal-Tibet border, sending a massive surge of water and debris downstream through the Bhotekoshi River and devastating settlements in northern and central Nepal, which killed more than 1,350 people, while around 5,000 remain missing.
On the Chinese side, the flash flood has killed 43 people, while 519 remain missing, according to authorities. The missing include 261 foreigners, of which 49 are from India.
The force of the mudslide, comprising huge boulders, ice and massive amounts of mud, wiped out the sprawling Chinese immigration centre building at Gyirong. Most of the dead and missing foreigners were on both sides of the building.
A group of foreign correspondents from Beijing, who were taken on a tour of the area by the Chinese Foreign Ministry on Sunday, saw that the entire area was devoid of any traces of the building, except for a few rods piercing out in some places.
The disaster has put the spotlight on the threats posed by the increasing volatility of the fragile environment in Tibet, the roof of the world, where around 10 transboundary rivers, including the Brahmaputra, originate.
Over the years, China has faced criticism over its hydropower projects, including the construction of a USD 167.8 billion dam on the Brahmaputra River in Tibet, which has been described as the world’s largest construction project, upstream of India’s Arunachal Pradesh.
Construction of the dam started in July last year. It is expected to generate more than 300 billion kWh of electricity each year, enough to meet the annual needs of over 300 million people.
The dam is being built at a gorge in the Himalayan reaches where the Brahmaputra River makes a huge U-turn before flowing into Arunachal Pradesh and then to Bangladesh.
While concerns earlier centred largely on earthquake risks, given Tibet’s location along the collision zone of the Indian and Eurasian tectonic plates, the August 26 disaster and its links to climate change and glacier retreat have added a new dimension to the risks facing the region.
Chinese researchers say climate change is emerging as a central driver behind the growing frequency and severity of such disasters across high-altitude border regions.
The August 26 event serves as a stark warning that rising temperatures are fundamentally reshaping the stability of the Qinghai-Tibet Plateau and the Himalayan range.
Chinese officials who addressed the media close to the site of the disaster said on Sunday that Tibet has 33,000 glaciers, with 187 of them categorised as high-risk which require round-the-clock satellite monitoring to predict collapse.
Nie Yong, a researcher at the Institute of Mountain Hazards and Environment of China, said there are now more than 14,000 glacial lakes on the Qinghai-Tibet Plateau, covering a combined area of more than 1,100 square kilometres, with many continuing to expand.
The area covered by glacial lakes in the region is increasing by an average of about one per cent a year, he told Chinese daily The Paper, warning that the continued expansion of the lakes is contributing to the accumulation of geological disaster risks in high-altitude areas.
Kang Shichang, director and researcher at the Institute of Mountain Hazards and Environment, under the Chinese Academy of Sciences in Chengdu, said glaciers across the Qinghai-Tibet Plateau had shrunk by about 24 per cent in area over the past six decades.
The decline has been even more pronounced in the southern part of the plateau, particularly in the Gangdise Mountains, Nyenchen Tanglha Mountains and the Himalayas, where glacier area has fallen by about 40 per cent over the same period, Kang told The Paper on Monday, attributing the dramatic retreat primarily to global warming.
The continued loss of glacier ice has also contributed to a substantial increase in the number and size of glacial lakes across the plateau, raising concerns over the risk of glacial lake outburst floods and related landslides.
The Paper said specialists examining the Gyirong Port mudslide have confirmed the disaster is closely tied to global warming.
The chain of events began with accelerated glacial melting driven by higher temperatures.
As glaciers retreat, they destabilise mountainsides, loosen rock and sediment, and create conditions where heavy precipitation or sudden structural failure can trigger cascading hazards, including ice-rock collapses that swiftly turn into massive mudflows.
As glaciers vanish, they leave behind unstable terrain and rapidly expanding glacial lakes, turning remote valleys into potential hazard zones and raising the possibility of more disasters.
