Nepal, Dec. 25 -- The Narayani River in Chitwan National Park is at only 180m above sea level, but on a rare clear day last week visitors could see the summit of 7,893m-high Himalchuli right across Nepal, 150km away.

Upstream, the Trisuli, Seti and Kali Gandaki join to form the Narayani in a catchment stretching 46,300 sq km from Dhaulagiri to Langtang - spanning one-third of Nepal's area.

Glaciers up in those mountains, and even a part of the Tibetan Plateau, feed the Narayani. To see the snows and river together underscores the need to regard the Himalaya not just as a mountain range, but as a composite watershed. This delicate balance between mountains and plains is now destabilised by climate breakdown.

"The climate crisis is a w...