Climate Change Will Affect the Asian Water Towers

TLDR

Over 1.4 billion people rely on water from the Indus, Ganges, Brahmaputra, Yangtze, and Yellow rivers, whose upstream snow and ice reserves are likely to be substantially altered by climate change, though the magnitude remains uncertain. Meltwater is crucial for the Indus and Brahmaputra basins but only modestly for the Ganges, Yangtze, and Yellow rivers, and climate‑change–driven reductions in flow are predicted to threaten the food security of about 60 million people in the Brahmaputra and Indus basins, highlighting large inter‑basin differences.

Abstract

More than 1.4 billion people depend on water from the Indus, Ganges, Brahmaputra, Yangtze, and Yellow rivers. Upstream snow and ice reserves of these basins, important in sustaining seasonal water availability, are likely to be affected substantially by climate change, but to what extent is yet unclear. Here, we show that meltwater is extremely important in the Indus basin and important for the Brahmaputra basin, but plays only a modest role for the Ganges, Yangtze, and Yellow rivers. A huge difference also exists between basins in the extent to which climate change is predicted to affect water availability and food security. The Brahmaputra and Indus basins are most susceptible to reductions of flow, threatening the food security of an estimated 60 million people.