Impact of Climate Change on Cryosphere — UPSC Environment Notes

The cryosphere — ice sheets, glaciers, sea ice, snow cover, permafrost, and frozen ground — covers about 10% of Earth's surface but drives climate well beyond its footprint. Warming is hitting the cryosphere harder than any other system: the Arctic is heating up nearly four times faster than the global average. For UPSC, the cryosphere sits at the intersection of climate science, water security, disaster risk (GLOFs), and geopolitics (the Arctic and Antarctic governance). This guide consolidates the physics, the impacts, and India's stake — with a special focus on the Third Pole (Hindu Kush Himalaya).

What is the cryosphere?

The cryosphere consists of:

Together they store roughly 70% of Earth's freshwater.

Why the cryosphere matters

1. Albedo feedback

Ice reflects 80–90% of incoming solar radiation; open water and dark ground absorb 80-90% of it. When ice retreats, more heat is absorbed — melting more ice. This ice-albedo feedback loop is one of the strongest amplifiers in the climate system.

2. Thermohaline circulation

Sea ice formation rejects salt, creating dense cold water that sinks — driving the Atlantic Meridional Overturning Circulation (AMOC). Freshwater from melting Greenland may be weakening the AMOC, a tipping point flagged by the IPCC.

3. Freshwater and sea level

Ice sheets and glaciers lock up freshwater; their melt adds directly to sea level rise. Thermal expansion of the oceans plus ice melt have driven global sea level up by roughly 20 cm since 1900, with the rate accelerating.

4. Ecosystems and species

Polar bears, snow leopards, reindeer, walruses, and countless ice-associated species depend on the cryosphere. Loss of sea ice habitat directly threatens their survival.

5. Carbon stores

Permafrost contains an estimated 1,500 gigatonnes of organic carbon — roughly twice the carbon currently in the atmosphere. Thawing permafrost releases CO2 and methane, a potent positive feedback.

How climate change is changing the cryosphere

Polar sea ice

• Arctic summer sea ice has declined by about 13% per decade (since 1979 satellite record).
• Projections: the Arctic may be practically ice-free during summers by 2050.
• Antarctic sea ice variability is more complex; 2023–24 saw record lows after decades of relative stability.

Ice sheets

• Greenland Ice Sheet is losing mass at about 270 Gt per year (surface melt dominating).
• Antarctic Ice Sheet is losing mass primarily from West Antarctica (Thwaites Glacier, the "Doomsday Glacier"); East Antarctica is more stable.
• Combined ice-sheet loss contributes around 1.5 mm/year of sea level rise.

Mountain glaciers and "Third Pole"

The Hindu Kush Himalaya (HKH) — covering India, Pakistan, Nepal, Bhutan, China, Afghanistan, Myanmar, Bangladesh — holds the largest ice mass outside the poles (the "Third Pole").

• ICIMOD's Hindu Kush Himalaya Assessment (2019) projected up to 1/3 of HKH glaciers will be lost by 2100 even at 1.5°C; 2/3 at higher warming.
• India's glaciers (e.g., Gangotri, Pindari, Siachen) show clear retreat.
• Chota Shigri, Dokriani, Dunagiri are long-monitored benchmark glaciers.

Permafrost

• The northern hemisphere permafrost is warming at around 0.3°C per decade.
• Thawing is already destabilising infrastructure in Russia, Alaska, Canada, and the Tibetan plateau.

Snow cover

• Northern Hemisphere spring snow cover has declined steadily since 1979.
• Changes in snow cover alter river runoff timing, affecting agriculture and hydropower.

Impacts — polar regions

• Shipping — the Northern Sea Route (Russia) and Northwest Passage (Canada) are opening for longer each year; new commercial traffic, military interest, and geopolitical tension follow.
• Resource extraction — Arctic oil, gas, and mineral prospects (governed partly by the Arctic Council) are rising despite environmental concerns.
• Biodiversity disruption — polar bears, walrus, Arctic fox, emperor penguins.
• Indigenous livelihoods — Inuit, Saami, and other Arctic peoples face upheaval.
• Governance — the Arctic Council, Antarctic Treaty System (1959), and Madrid Protocol (1991) are being stress-tested.

Impacts — mountain cryosphere (acute for India)

Water security

• Himalayan rivers — Ganga, Brahmaputra, Indus — feed 1.5-2 billion people. Glacier runoff is projected to peak mid-century, then decline, producing a "water tower in reverse" scenario.
• Black carbon deposition from biomass burning and diesel compounds glacier melt.

GLOFs — Glacial Lake Outburst Floods

• New glacial lakes form as glaciers retreat; moraine dams can burst catastrophically.
• October 2023 South Lhonak Lake GLOF (Sikkim) destroyed Teesta-III hydropower dam and killed over 75 people; February 2021 Chamoli disaster in Uttarakhand was a similar ice/rock avalanche cascade.
• India's NDMA GLOF Guidelines (2020) and ISRO's Glacial Lake Atlas track lakes and their risk.

Hydropower and agriculture

• Altered river runoff affects dams (Bhakra, Tehri, Teesta), irrigation, and downstream agriculture.
• Peak runoff first increases, then falls as glaciers shrink — the "peak water" phenomenon.

Tourism and livelihoods

• Ski tourism, mountain trekking, and pilgrimage (Amarnath, Kedarnath) face direct and indirect disruption.
• Melting glaciers expose more land to unsafe tourism, worsening ecological degradation.

India's policy response

Latest developments (2024–26)

Updated context: cross-check specific figures with the latest IPCC AR6 synthesis and the 2024 Arctic Report Card.

• COP29 Baku (2024) — reaffirmed focus on 1.5°C alignment; cryosphere linkages highlighted in the Global Stocktake follow-up.
• COP30 Belém (2025) — Brazil pushed a Tropical Forests Forever Facility; cryosphere losses cited as a key tipping-point driver.
• South Lhonak GLOF impact assessment continues to reshape Himalayan hydropower planning.
• India–ICIMOD collaboration expanded — particularly on transboundary data sharing with Nepal and Bhutan.
• IPCC AR7 cycle — began 2024 with new Synthesis Report scheduled for 2028.

UPSC relevance

GS-III mapping

• Conservation and environmental pollution.
• Disaster and disaster management (GLOFs).
• Science and technology (remote sensing for cryosphere).

Prelims bullets

• The Third Pole refers to the Hindu Kush Himalaya region.
• Permafrost is ground at ≤0°C for ≥2 consecutive years.
• India's Antarctic stations: Dakshin Gangotri (1983, decommissioned), Maitri (1989), Bharati (2012).
• Indian Antarctic Act, 2022 regulates India's Antarctic activities.
• NMSHE is one of the 8 NAPCC Missions.
• ICIMOD is headquartered at Kathmandu, Nepal.

Mains angles

• “Discuss the impact of climate change on the cryosphere and its cascading effects on India’s water, energy, and disaster profile.”
• "Examine the factors making the Himalayan cryosphere particularly vulnerable to climate change and India's policy response."
• "What are Glacial Lake Outburst Floods? Discuss their increasing frequency in the Indian Himalayas with recent examples."

Essay hooks

• The cryosphere as the "early warning system" of the climate.
• India as a cryosphere power — glaciers, Antarctic and Arctic stakes.
• Transboundary water governance in a melting Himalaya.

Quick revision

Bottom line for UPSC: the cryosphere is the climate's ledger — it records every joule of heat with a millimetre of sea level or a gram of methane. India's cryosphere stake is larger than most realise: the Third Pole's glaciers feed more than a billion Indians, and their future decides India's water future.