ESA – Revealing invisible Himalaya glacier loss

The new findings, which were published in the journal Nature Geoscience this week, found that values of ice lost from Himalayan glaciers that terminate in lakes during 2000 to 2020 were, on average, underestimated by 6.5%.

Digital elevation models based on satellite data have been used widely to estimate ice loss from glaciers. However, meltwater from glaciers often ends up as proglacial lakes – lakes that form in front of the ice. In effect, the glacial ice is replaced by lake water.

The traditional digital elevation model method of estimating ice loss measures the glacier and water surface but does not account for any ice loss that occurs below the surface of a lake.

The Himalayas and many other mountains have thousands of proglacial lakes, many of which are rapidly expanding. Yet, the contribution of subaqueous mass loss to total glacier mass loss has been largely neglected – until now.

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