The massive 'water towers' of the Himalayas aren't just melting glaciers; they’re actually being fed by giant underground pools of water.
EarthArXiv · March 16, 2026 · 10.31223/X53T91
Why it matters
Climate and water-security plans for Asia usually focus almost entirely on disappearing ice. This study reveals that even at extreme altitudes, groundwater—not glacier melt—is the primary engine driving river flow during the monsoon, acting as a secret, giant sponge that sustains the region's water supply.
From the abstract
Himalayan water-security assessments often focus on glacier retreat, yet groundwater may supply much of river flow. We combine seismic observations from the Hi-CLIMB transect across Nepal (2002–2004) with gauged discharge, satellite precipitation, and glacier-cover inventories to resolve when streamflow is sustained by melt versus groundwater. Relative seismic velocity changes track hillslope pore pressure and groundwater recharge, while river-induced seismic noise amplitudes provide a proxy for