On 26 August, a wall of water, ice and rock came down the Bhotekoshi valley in northern Nepal. It began high in the Himalayas near Langtang Lirung, where a glacier collapsed. The debris flow travelled close to 100 kilometres through Rasuwa, Nuwakot, Dhading and further downstream. The collapse was violent enough to register as a magnitude 5.2 event on seismometers around the world. It reached the Rasuwagadhi border crossing within minutes, which left almost no time to warn anyone. More than 1,100 people are confirmed dead. Close to 4,000 are still missing. Around 12,000 have been rescued. Homes, bridges, highways and hydropower plants are simply gone. All figures remain provisional. Prime Minister Balen Shah told parliament this week that the disaster is a warning about how fast risk is rising in the Himalayan region, and that managing it is a collective global responsibility. Nepal has gone further than a relief appeal. It has named India, China and the United States as major emitters and asked for compensation rather than aid, while formally approaching the UN Fund for Responding to Loss and Damage. Foreign Minister Shishir Khanal called it a shift from aid to justice, and framed it as legal and moral liability rather than charity. Scientists are being careful here, and that care matters. Working out how much warming contributed to this specific collapse will take time. What is not in question is the direction of travel. Thawing permafrost and retreating ice are making high mountain slopes less stable, and these events are becoming more frequent across the Himalaya, the Andes and the Alps. That is the uncomfortable part for those of us who work in this field. Nepal contributes a rounding error to global emissions and is holding a bill it did not run up. Loss and damage stopped being a line item in a negotiating text on 26 August. It became a valley in Rasuwa with nothing left in it. **Nepal's ask deserves a serious answer, not a polite one.**
