Not just a flood: Dangerous chain reaction behind Nepal’s deluge, creating new flood risk

Nepal’s devastating flash floods were triggered by a dangerous chain reaction involving an ice-rock collapse, river blockage and the sudden release of massive amounts of water, mud and debris. In this explainer, we break down how the Himalayan terrain amplified the destruction, why scientists are watching glacier and permafrost changes, and what the latest warning means. Could newly formed debris blockages and natural dams trigger another flood downstream? Here’s what caused Nepal’s mega flood and why the danger may not be over.