Bloomberg reports:

The giant wave of rock, ice and debris that swept through 100 kilometers (62 miles) of Nepalese valleys last week is the deadliest illustration yet of how climate change is fueling mountain disasters of epic proportions.

Scientists have long predicted quicker melting of snow and ice and accelerated thawing of permafrost in high mountain areas that are warming twice as fast as the rest of the planet. For years they have documented the results: more frequent rockfalls, avalanches, lake outbursts, flash floods and landslides.

Even so, the sheer scale of the disaster in Nepal shocked experts. “There are things that we’re completely unprepared for,” said Noah Diffenbaugh, a climate scientist at Stanford University. The floods fall into the category of “things that are just completely outside of our experience.”

The event was triggered on Aug. 26 when the bedrock gave way below a glacier near the Langtang Lirung peak in the Nepalese Himalayas. A huge section of the glacier, measuring between 1 and 1.3 kilometers wide, detached from the mountain, dragging vast amounts of debris with it as it slid from an altitude of about 5,200 meters (17,000 feet) above sea level. The fast-moving deluge raised water levels in rivers downstream by as much as 9 meters within just half an hour.

It’s among the catastrophic mountain incidents that climate scientists would have classed as outliers not long ago, but that are now happening more regularly. Last year alone, three glacial lakes burst in Nepal, flooding valleys downstream, with one occuring on the same river as last week’s mega-event. In 2024, the village of Thame in Nepal’s Everest region was flooded, while in 2023 India’s Sikkim and Himachal Pradesh states were deluged. All told, hundreds of people died in these disasters, which were reported in foreign media but did not capture the attention of the world. [Continue reading…]