"If an ice-rock avalanche can be detected upstream, it is theoretically possible to provide downstream communities with about 20 minutes of warning," said Kang Shichang, director of the Institute of Mountain Hazards and Environment at the Chinese Academy of Sciences in Chengdu, Sichuan province.

　　But the disaster occurred in a remote Himalayan area characterized by deep valleys and high mountains, where monitoring infrastructure is limited. The floodwater also reached the border rapidly, further shortening the available warning time, Kang said.

　　The disaster highlights a concern that climate change is reshaping the hazards of the Qinghai-Tibet Plateau and surrounding mountains.

　　Du Jun, director of the climate center of the Xizang regional meteorological bureau, said global warming is driving changes in glaciers, permafrost and snowfall that can increase the frequency and complexity of high-altitude disasters.

　　Glacier retreat can expand glacial lakes and increase the volume of water they hold, raising the risk of glacial lake outburst floods. "It also exposes more loose glacial debris, increasing the amount of material available to mudslides, while greater meltwater can strengthen erosion and the capacity of rivers to transport debris," Du told China Daily.

　　At the same time, permafrost degradation weakens slopes and foundations, and changes in groundwater and runoff can intensify erosion.

　　In southern Xizang, the number of snow-cover days has declined significantly since 1981, falling by an average of 12.36 days every decade, according to Du.

　　A shorter snow-cover season can alter the timing and intensity of spring snowmelt, while reducing the buffering effect of snow cover and increasing erosion, he said.