Nepal's deadly flood: causation, devastation, and preventive measures.

What caused Nepal's deadly flash floods, what's now threatening rescue efforts, and how can it be stopped from happening again? Analysts say a huge chunk of glacier plunged more than a kilometre into a valley near the Nepal-China border, sending walls of water through communities below and leaving more than 1,000 people reported missing. The collapse left behind debris that has formed unstable "barrier lakes," held back only by weak walls of loose rock. If those walls give way, millions of cubic litres of water could surge downstream, adding to the danger already posed by glacial lakes scattered across the Himalayas, some formed as melting glaciers leave deep holes that fill with water, others dammed by soil pushed up by moving ice. A 2022 study found climate change has increased glacial avalanches and landslides, causing more of these lakes to burst their banks. In response, Chinese President Xi Jinping has ordered upgrades to disaster warning systems, while researchers are also proposing slowly draining high-risk lakes and cutting emissions to stabilise glaciers in the long term. Al Jazeera's Perry Wilton explains. Subscribe to our channel: http://bit.ly/AJSubscribe Follow us on Twitter: https://twitter.com/AJEnglish Find us on Facebook: https://www.facebook.com/aljazeera Check our website: http://www.aljazeera.com/ Check out our Instagram page: https://www.instagram.com/aljazeeraenglish/ Download AJE Mobile App: https://aje.io/AJEMobile #Nepal #China #GlacierCollapse #FlashFlood #Himalayas #ClimateChange #NaturalDisaster #Asia #AlJazeera #AlJazeeraEnglish