Published on 23 Feb 2025
The cryosphere refers to all the frozen parts of Earth's surface and subsurface. It comes from the Greek word "kryos" which means "cold" or "icy". The cryosphere includes:
Snow on the ground
Lake and river ice
Frozen ground and permafrost (ground that is permanently frozen)
The Antarctic and Greenland Ice Sheets, ice caps, and glaciers
Ice shelves and icebergs
Sea ice
Significance of Cryosphere
Climate Regulator: The cryosphere acts like Earth's giant mirror, reflecting sunlight back to space with its high albedo (reflectivity) of ice and snow. This helps maintain cooler global temperatures.
Freshwater Reservoir: The cryosphere holds a massive amount of freshwater (around 69%) stored in glaciers, ice caps, and ice sheets. It's a crucial source for drinking, agriculture, and maintaining global water availability.
Massive Carbon Storage: Arctic permafrost holds a staggering amount of carbon – twice the amount currently in the atmosphere! This frozen ground acts as a natural carbon bank.
Supports Diverse Ecosystems: The cryosphere sustains unique ecosystems, especially in polar regions. It provides habitat for over 14,000 terrestrial species in the Arctic alone.
Linked to SDGs: The cryosphere is intricately connected to several UN Sustainable Development Goals (SDGs), including Climate Action (SDG 13), Freshwater availability (SDG 6), and Biodiversity (SDG 15).
Impact of Climate change on Cryosphere
Shrinking Cryosphere:
Global Warming's Grip: Rising temperatures, fuelled by greenhouse gases, are causing widespread shrinkage of glaciers, ice sheets, and permafrost.
Glacier Retreat: The thickness of glaciers worldwide has plummeted by a staggering 30 meters since 1970 (World Meteorological Organization (WMO) report 2022). The Hindu Kush Himalayan region is particularly vulnerable.
Sea Ice Decline: Both Arctic and Antarctic Sea ice have hit record lows, with Antarctic Sea ice falling 1 million square kms below the long-term average (1991-2020).
Rising Seas:
Melting Ice, Rising Waters: The melting of glaciers and ice sheets, combined with warming seawater expansion, is pushing sea levels to new highs.
Accelerating Rise: Sea level rise has doubled between 1993-2002 and 2013-2022 (WMO data) threatening coastal communities.
Permafrost Thaw Threat:
Permafrost Thawing: Permafrost, a vast reservoir of frozen soil and greenhouse gases, is thawing at an alarming rate.
Carbon sink opens up: Permafrost holds twice the amount of carbon currently in the atmosphere. Thawing releases these gases, accelerating warming.
Paris Agreement Threshold: At a 1.5°C temperature rise (Paris Agreement target), permafrost thaw could release a staggering 150-200 gigatonnes of carbon dioxide.
Vicious Feedback Loop:
Melting Exposes, Warming Intensifies: As ice and snow melt, darker surfaces are revealed, absorbing more heat and further accelerating warming. This creates a vicious feedback loop.
Disrupted Ocean Circulation:
Melting Ice, Shifting Currents: Melting ice, particularly from glaciers and ice sheets, disrupts ocean circulation patterns.
Global Impact: Ocean currents play a crucial role in distributing heat around the planet, influencing regional climates. Changes in these currents can have far-reaching consequences.
Socio-Economic Fallout:
Water Woes: Loss of mountain glaciers and snowpack in mid-latitude and tropical regions impacts over 3 billion people.
Economic Strain: Regions like the Andes, western US, Scandinavia, and the Alps are highly dependent on the cryosphere for activities like agriculture, power generation, and tourism. A shrinking cryosphere poses a significant economic threat.
Himalayan Woes: Changes in the Hindu Kush Himalayan region threaten water availability for over 2 billion people. This can lead to flooding, landslides, and disruptions in agriculture.
Initiatives to protect Cryosphere
Global Initiatives:
ICCI (International Cryosphere Climate Initiative): They focus on the unique climate dynamics of the cryosphere and advocate for stronger global climate action.
GCW (Global Cryosphere Watch: Aims to enhance systematic observation and monitoring of the cryosphere and provide essential data for assessing changes in the cryosphere.
The Arctic Council: This intergovernmental body, promotes cooperation among Arctic nations to protect the Arctic environment and support the economic, social, and cultural well-being of the indigenous people.
India's Initiatives:
NMSHE (National Mission for Sustaining the Himalayan Ecosystem): Launched in 2010, NMSHE is one of eight missions under India's National Action Plan on Climate Change (NAPCC).
PACER (Polar Science and Cryosphere Research): This umbrella scheme consolidates all Indian scientific and logistical programs in polar regions. It encompasses four elements: the Antarctic program, the Indian Arctic program, the Southern Ocean program, and the Cryosphere and Climate program. PACER is successfully implemented through the National Centre for Polar and Ocean Research (NCPOR).
Way Forward
Global climate action needed: Protecting the cryosphere requires vigorous international cooperation and strong climate action plans, as the impacts of a changing cryosphere extend far beyond mountainous and polar regions.
Limit temperature rise to 1.5°C: Limiting global warming to 1.5°C as outlined in the Paris Agreement is crucial to minimize cryosphere loss and the resulting chain reactions like sea level rise and disruptions to weather patterns.
Prioritize pre-2030 emissions reductions: Urgent reductions in greenhouse gas emissions before 2030 are essential for the well-being of all societies.
Geography
CLIMATE CHANGE
CRYOSPHERE
Significance of Cryosphere
Impact of Climate change on Cryosphere
Initiatives to protect Cryosphere
General Studies Paper 1
Physical Geography