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Environment › Climate science

Cryosphere, oceans and sea level

Ice, oceans and the rising sea: glaciers and glacial lakes, permafrost, polar ice, ocean heat and acidity, and sea level. Prelims has asked which rivers rise from which Himalayan glaciers, and about the source and course of the Teesta.

Showing 1 of 5 subjects, those that changed from 16 to 31 July 2026.Show all

Prelims and Mains

Most of the lakes that threaten Indian valleys are not in India, which makes a warning system a question of what neighbours are willing to share.

  • The Glacial Lake Atlas of the National Remote Sensing Centre (NRSC) maps 28,043 lakes in the Himalayan river basins, almost 73 per cent of them outside India.
  • The NRSC works under the Indian Space Research Organisation (ISRO), and the Defence Geoinformatics Research Establishment under the Defence Research and Development Organisation (DRDO).
  • Data sharing with China and Nepal is therefore part of the warning system rather than a courtesy.
  • Ladakh3,219

  • Arunachal Pradesh2,188

  • Sikkim733

  • Jammu and Kashmir546

  • Himachal Pradesh537

  • Uttarakhand347

Mapped glacial lakes inside India, of at least 0.25 hectares. From Frontline, 1 September 2026, citing the NRSC Glacial Lake Atlas

What changed

  1. 1 Sep 2026

    Frontline, 1 Sep 2026: India can see the danger in the Himalaya. Can it manage the risk? (opens in a new tab)

  2. 29 Jul 2026Update

    • ISRO has built a database of more than 2,000 glaciers in Ladakh and an inventory of 3,219 glacial lakes larger than 0.25 hectare, prepared under the National Hydrology Project.
    • Outburst flood risk has been modelled for the high risk lakes, and a satellite based landslide alert system has issued village level alerts in Ladakh since 2023.

    PIB, 29 Jul 2026: PARLIAMENT QUESTION: SPACE TECHNOLOGY FOR DISASTER MANAGEMENT IN LADAKH (opens in a new tab)

Also filed elsewhere

  • Hydropower in the Himalaya · on Wind, hydro and other renewables

    The mountains hold most of the fall a turbine wants and most of the hazard a project cannot survive.