A large glacier collapsed near the border of Nepal and Tibet. This caused terrible flash floods in the Himalayan region. The water in the rivers rose by seven to nine metres in only 30 minutes. This happened very fast and destroyed many areas. At first, people thought an earthquake caused a landslide. However, scientists now say a glacier collapse caused the disaster. This collapse created a fast flow of water, rocks, and dirt.
Many people died in this disaster. Nepali police say at least 359 people died. Many more people are still missing. The National Disaster Risk Reduction and Management Authority says 826 people are missing. This group includes more than 529 tourists. Among them, 466 are foreigners. The Nepal Tourism Board says 644 tourists are missing, including 33 people from the United Kingdom.
Dr. Simon Cook is a glacier expert from the University of Dundee. He found that the lower part of a glacier near the Langtang Lirung peak collapsed. This peak is about 15km (9 miles) west of the most damaged area. The mountains are steep, so the water and rocks moved very quickly down the valleys. The impact of the collapse was a magnitude 5.2.
Scientists say two things are causing this problem. First, the mountains are still moving upward. Second, climate change is making the world warmer. This causes glaciers to melt very fast. ICIMOD says glaciers in the Hindu Kush Himalaya region are losing ice at double the rate seen since the year 2000. This makes the area very dangerous for local people and tourists.