What were the key findings of the 2025 expedition to the Eastern Himalayas?

The expedition team successfully conducted high-resolution aerial surveys of the Khangri Glacier and Rani Lake, and completed the first scientific scaling and reconnaissance of Dharkha Tso, a glacial lake identified as susceptible to outburst floods.

How did the 2025 expedition team overcome the challenges of accessing the glacial regions?

The team trekked through heavy snowfall and treacherous terrain, navigating low oxygen levels, steep ridges, and hazardous gorges to reach the remote Dharkha Tso lake.

What is the significance of the expedition's findings for understanding the Eastern Himalayan cryosphere?

The expedition's successful completion marks a significant step forward in India's scientific efforts to study glacier health, meltwater contribution, hydrometeorological patterns, and glacial lake outburst flood risks in the region.

Home / Science / Drone Surveys and Sonar Mapping Reveal Surprises in Eastern Himalayan Glaciers

Drone Surveys and Sonar Mapping Reveal Surprises in Eastern Himalayan Glaciers

15 Nov

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Summary

Joint expedition by Centre for Earth Sciences and National Centre for Polar and Ocean Research
Successful aerial surveys and bathymetric mapping of Khangri Glacier and Rani Lake
First scientific scaling and reconnaissance of Dharkha Tso, a GLOF-susceptible lake

Drone Surveys and Sonar Mapping Reveal Surprises in Eastern Himalayan Glaciers

In November 2025, a joint expedition led by the Centre for Earth Sciences and Himalayan Studies (CESHS) and the National Centre for Polar and Ocean Research (NCPOR) has made significant progress in the scientific understanding of glacier dynamics, climate change impacts, and water resource sustainability in the Eastern Himalayas.

The week-long expedition, which took place from November 8 to 14, 2025, successfully carried out high-resolution aerial surveys of the Khangri Glacier and the Rani Lake using advanced drone platforms equipped with precision sensors. A notable achievement was the unmanned sonar-based bathymetric survey of Rani Lake, which revealed the presence of aquatic life at a depth of 20 metres, an important finding in this high-altitude glacial environment.