Cryosphere, Himalayan Glaciers & Polar Regions — Climate & Security Implications

What Is the Cryosphere?

The cryosphere encompasses all frozen water on Earth — glaciers, ice sheets, sea ice, permafrost, snow cover, and ice caps. It plays a foundational role in regulating Earth's energy balance, freshwater availability, ocean circulation, and global climate.

The cryosphere is a critical planetary thermostat: its white surfaces reflect incoming solar radiation (the albedo effect), keeping the planet cooler. As ice melts, darker ocean or land is exposed, absorbing more heat — a self-amplifying positive feedback loop.

Components of the Cryosphere

Together, these components store approximately 75% of all Earth's freshwater. Their accelerating loss is one of the defining crises of the 21st century.

The Himalayan Glaciers — Earth's "Third Pole"

The Hindu Kush Himalayan (HKH) region is called the "Third Pole" because it contains the largest concentration of glaciers and permanent ice outside the polar regions. This region covers over 5 million km² and stretches from Afghanistan in the west to China in the east, encompassing the Pamir-Hindu Kush, Himalayan, Hengduan, Tien Shan, and Qilian mountain ranges.

Key Facts — Third Pole

• The Third Pole holds approximately 100,000 km² of glacial ice
• It is the source of 10 major river systems: Ganges, Indus, Brahmaputra, Amu Darya, Syr Darya, Mekong, Yellow, Yangtze, Irrawaddy, and Salween
• These rivers sustain freshwater supply for approximately 2 billion people — around 25% of the world's population
• The HKH region contains ~12,000 lakes, many glacially fed

Within the Indian Himalayan Region, the National Remote Sensing Centre (NRSC) has mapped over 7,500 glacial lakes, out of approximately 28,000 in the broader HKH region.

Indian Himalayan Glaciers

India's Himalayan glaciers are distributed across the western, central, and eastern Himalayas. Key facts:

• Glaciers are receding across the board — the rate varies by region and glacier
• The Siachen Glacier (Karakoram Range) is the world's second-longest non-polar glacier and has strategic military significance
• The Zemu Glacier (Sikkim) is the largest glacier in the Eastern Himalayas
• The Gangotri Glacier (Uttarakhand) is the source of the Bhagirathi river, a headwater of the Ganga

Gangotri Glacier — Retreat Data

The Gangotri Glacier's retreat has accelerated measurably over recent decades:

• Between 1936 and 1996, the glacier retreated approximately 1,147 metres at an average of ~19 m/year
• After 1996, retreat accelerated to approximately 22–38 metres per year
• Studies measuring the period 1993–2021 recorded a cumulative retreat of approximately 1,850 metres
• The snout of the glacier (mouth of Gaumukh) has moved significantly upstream

This acceleration is consistent with rising temperatures and reduced winter snowfall across the western Himalayas.

Glacial Lake Outburst Floods (GLOFs)

Mechanism

As glaciers retreat, meltwater collects behind unstable natural dams of ice or moraine (glacial debris). When these dams fail — due to an avalanche impact wave, seismic activity, or moraine weakness — a sudden catastrophic release of water rushes downstream: a Glacial Lake Outburst Flood (GLOF).

GLOFs can release tens of millions of cubic metres of water in minutes, generating flash floods that travel hundreds of kilometres and destroy infrastructure, farmland, and settlements downstream.

India's Major GLOF Events

Chamoli, Uttarakhand — 7 February 2021

A massive rock and ice avalanche (~22 million m³ of material) from Ronti peak crashed into the Ronti Gad valley. Although initially described as a GLOF, later research confirmed it was a rock-ice avalanche (LLOF — landslide-lake outburst flood) rather than a glacial lake breach, as no significant glacial lake existed in the area. The resulting flash flood swept down the Rishi Ganga, Dhauliganga, and Alaknanda rivers, killing or leaving missing more than 200 people — predominantly workers at the Tapovan Hydropower Project. The disaster occurred against a background that January 2021 was the warmest January in Uttarakhand for six decades.

South Lhonak Lake, Sikkim — 3–4 October 2023

A true GLOF of major scale. On 3 October 2023, a permafrost landslide caused approximately 14.7 million cubic metres of frozen lateral moraine to collapse into South Lhonak Lake at ~5,200 m elevation. The impact generated a tsunami-like wave of ~20 metres, breaching the moraine dam and releasing approximately 50 million cubic metres of water. The ensuing flood eroded ~270 million cubic metres of sediment. Key impacts:

• The 1,200 MW Teesta-III dam was destroyed
• The flood wave traveled 385 km along the Teesta River into Bangladesh
• At least 92 confirmed deaths as of 18 October 2023
• South Lhonak Lake had grown from 0.2 km² (1976) to 1.67 km² (2023) due to glacial retreat driven by climate change

Scientific studies confirmed that climate change played a key role in the disaster by expanding the lake to a critical size. Sikkim accounts for the highest number of very high-risk glacial lakes among Indian states (20 out of 28 classified as very high risk nationally).

India's GLOF Risk Landscape

• NDMA (National Disaster Management Authority) has identified 195 high-risk glacial lakes expanding rapidly in the Indian Himalayas
• The Central Water Commission (CWC) monitors 902 glacial lakes and water bodies (larger than 10 ha) via remote sensing
• NDMA issued formal Guidelines for GLOF Management in October 2020

IPCC Findings — Cryosphere Under Threat

SROCC 2019 (Special Report on the Ocean and Cryosphere in a Changing Climate)

The IPCC's landmark 2019 SROCC report confirmed:

• Ice sheets and glaciers worldwide have lost mass (very high confidence)
• The Greenland Ice Sheet lost ice at an average of 278 ± 11 Gt/year (2006–2015), primarily due to surface melting
• The Antarctic Ice Sheet lost ice at an average of 155 ± 19 Gt/year (2006–2015), mainly from rapid thinning of West Antarctic outlet glaciers
• Mountain glaciers in some regions are projected to lose more than 80% of their current ice mass by 2100 under high-emission scenarios
• Global-scale glacier mass loss will continue in the near-term (2031–2050) regardless of emissions scenario — some loss is already locked in

IPCC AR6 (2021–22) — Sea Level Rise Projections

The IPCC Sixth Assessment Report provides the following global mean sea-level rise projections by 2100 (relative to 1995–2014):

Beyond 2100, ice sheet dynamics — particularly the potential instability of the West Antarctic Ice Sheet — could drive further acceleration that is difficult to constrain.

Arctic Changes — Amplification and Consequences

Arctic Amplification

The Arctic is warming nearly four times faster than the global average (based on 1979–2021 data published in Communications Earth & Environment, 2022). This phenomenon, called Arctic amplification, is driven by:

1. Albedo feedback — as sea ice retreats, dark ocean absorbs more heat instead of reflecting it
2. Ice-albedo feedback amplification — the warming accelerates further ice loss
3. Lapse rate feedback — in the Arctic, surface warming is not distributed through the atmosphere as efficiently as in the tropics
4. Water vapour and cloud feedbacks — increased moisture amplifies warming

Key Arctic Indicators

Permafrost — The "Carbon Bomb" Risk

Permafrost soils contain an estimated twice as much carbon as is currently present in the atmosphere. As permafrost thaws:

• Microbial activity decomposes organic matter, releasing CO₂ and methane
• Methane is a particularly potent greenhouse gas (GWP ~80x CO₂ over 20 years)
• This creates a positive feedback loop: warming thaws permafrost → more GHG released → more warming
• Scientists estimate methane emissions from permafrost-affected tundra sites are already increasing at roughly 1.9% per year (since 2004, Lena River Delta data)
• The Arctic may be shifting from a net carbon sink to a net carbon source

The Northern Sea Route (NSR)

Arctic sea ice loss is opening new maritime shipping routes. The Northern Sea Route (along Russia's Arctic coast) could reduce the distance between Europe and East Asia by ~40% compared to the Suez Canal route. This has major geopolitical and trade implications, including for India's shipping interests.

Arctic Geopolitics and India

Arctic Council

India's Arctic Policy 2022

India released its first Arctic Policy in March 2022 — "India and the Arctic: Building a Partnership for Sustainable Development" (Ministry of Earth Sciences). The policy covers six pillars:

1. Science and research
2. Climate and environmental protection
3. Economic and human development
4. Transportation and connectivity
5. Governance and international cooperation
6. National capacity building

India's Arctic Research — Himadri Station

• Name: Himadri Research Station
• Location: Ny-Ålesund, Svalbard (Norway) — approximately 1,200 km from the North Pole
• Established: July 2008 (India's second Arctic expedition)
• Operated by: National Centre for Polar and Ocean Research (NCPOR), Goa
• Research focus: Atmospheric science, aerosols, glaciology, space weather, fjord dynamics (Kongsfjorden), microbial communities, carbon cycling
• India is among the 11th group of nations to establish a permanent station at Ny-Ålesund

Antarctica — The Southern Ice Giant

Ice Sheets

Antarctica holds approximately 26.5 million km³ of ice — enough to raise global sea levels by about 58 metres if fully melted (an unlikely scenario, but illustrative of the scale).

West Antarctic Ice Sheet (WAIS): The WAIS is considered particularly vulnerable because much of it sits on bedrock below sea level (a marine ice sheet). The Thwaites Glacier and Pine Island Glacier — both draining the WAIS — have been destabilising. Studies suggest the WAIS contains ice equivalent to approximately 3.3 metres of potential sea-level rise and could be past a tipping point at current warming levels. Mass loss from the WAIS has been averaging approximately 150 Gt/year since 2002.

East Antarctic Ice Sheet (EAIS): The EAIS is far larger and currently shows net mass gain due to increased snowfall on its surface, partially offsetting WAIS losses. However, outlet glaciers along the Wilkes Land coast show signs of instability.

India's Antarctic Research Programme

India's Antarctic engagement dates to 1981 (first Indian expedition). India currently operates two permanent research stations:

India has also approved plans for a third station, Maitri II, to replace the ageing Maitri infrastructure (expected operational ~2029).

National Centre for Polar and Ocean Research (NCPOR): Headquartered in Vasco da Gama, Goa, NCPOR is the nodal agency for all Indian polar research (Arctic, Antarctic, and Southern Ocean). It plans and coordinates annual scientific expeditions.

Sea Level Rise — India's Coastal Vulnerability

IPCC AR6 projects sea-level rise of 0.28–0.55 m by 2100 under the lowest emission scenario (SSP1-1.9). Under higher scenarios, this could exceed 1 metre.

India's specific vulnerabilities:

• India has a 7,516.6 km coastline and over 250 million coastal residents
• Low-lying deltaic regions — Sundarbans (West Bengal), Mahanadi delta (Odisha), and parts of Kerala and Tamil Nadu — face severe inundation risk
• Lakshadweep and Andaman & Nicobar Islands could lose significant land area
• Mumbai's Bandra-Kurla Complex and Nariman Point are already at risk from storm surges; sea-level rise amplifies this exposure
• Freshwater security: as coastal aquifers face saltwater intrusion, drinking water and agricultural water supplies are threatened
• Extreme weather intensification: warmer ocean surfaces and melting ice alter monsoon dynamics, potentially leading to more erratic rainfall patterns

Policy Responses — India and Global

National Mission for Sustaining the Himalayan Ecosystem (NMSHE)

One of India's eight National Missions under the National Action Plan on Climate Change (NAPCC, 2008). NMSHE was formally launched in 2010 and approved by the Union Government in 2014 (under the Ministry of Science and Technology). Its objectives:

• Assess and monitor the health of Himalayan glaciers, river systems, and ecosystems
• Develop policies to sustain ecological resilience in the Himalayas
• Build national capacity for continuous health-status assessment

HIMAP — Hindu Kush Himalayan Monitoring and Assessment Programme

HIMAP is an ICIMOD-led (International Centre for Integrated Mountain Development) long-term monitoring and assessment initiative covering the HKH region. It brings together researchers, policymakers, and practitioners to generate evidence for sustainable mountain development. HIMAP's comprehensive assessments inform national and regional climate adaptation planning across the HKH countries.

Other Relevant Policies

Prelims Quick-Reference Table

Mains Relevance

GS3 — Environment; Disaster management (GLOFs, coastal flooding); Science & Technology (polar research)

GS1 — Geography (Himalayan rivers, glacial landforms); Physical geography of India

Likely Mains angles:

• "The cryosphere is melting faster than models predicted. Examine the implications for India's water security, coastal stability, and foreign policy." (250 words)
• "Evaluate India's polar research programme and its strategic significance." (150 words)
• "GLOFs are becoming more frequent in the Indian Himalayas. Discuss the causes and suggest a policy framework for risk reduction." (250 words)

Key linkages:

• Connect to Ch 24 (Climate Change Adaptation) for policy responses
• Connect to Ch 22 (Coastal Ecosystems) for sea-level rise and coastal impacts
• Connect to Ch 12 (River Conservation) for Himalayan river systems
• For current affairs integration on recent GLOF events, refer to Ujiyari.com