What IMD said about Nepal flash floods: Glacier lake outburst, alert for Gandak river

A massive 2,000-foot-wide chunk of glacier broke free from the mountains and plummeted down a river valley in Nepal, triggering devastating flash floods. Geologists and glaciologists suggest the event was an ice avalanche, a sudden collapse where a large mass of ice falls from a glacier, producing a powerful surge of water, ice, and debris.

The shattered ice plummeted nearly 4,000 feet before colliding with the Lhende Khola and Bhotekoshi Rivers near the Nepal-China border. The aftermath was described as catastrophic, with the bottom of the valley resembling a "bomb exploded," littered with pulverized ice and water.

Initially, the energy stored in the falling glacier created a devastating wave of water and debris, sweeping through settlements, roads, bridges, and hydropower infrastructure. While the exact sequence of events remains uncertain, it's possible an earlier magnitude 4.4 earthquake or an ice-rock avalanche contributed to the disaster.

Scientists caution that it's too early to determine the single cause of the tragedy, as temperatures in the Himalaya continue to rise, increasing the vulnerability of the region to floods, landslides, and glacier-related hazards. The disaster has resulted in dozens of deaths and hundreds of people still missing, leaving communities along Nepal's steep Himalayan valleys in shock.