Syllabus
GS Paper 3 – Conservation, Environmental Pollution and Degradation, Environmental Impact Assessment
GS Paper 1 – Important Geophysical Phenomena such as earthquakes, Tsunami, Volcanic activity, cyclone etc., geographical features and their location-changes in critical geographical features (including water-bodies and ice-caps) and in flora and fauna and the effects of such changes.
Context
The World Meteorological Organization’s latest report, “The Global Climate 2011 – 2020,” notes that, on average, glaciers worldwide underwent an annual thinning of about one meter from 2011 to 2020 in the section discussing glacier health
Source
The Hindu | Editorial dated 11- December 2023
Glacier Formation:
- Glaciers are massive blocks of moving ice.
- Glaciers take thousands of years to form.
- They form as accumulated snow in cold regions compacts and recrystallizes.
- Examples include mountains and polar glaciers, distinct from large Arctic plates.
Glacier Classification:
- Classified based on morphology: ice fields, cirque glaciers, valley glaciers, etc.
- Classification by climate: polar, tropical, or temperate.
- Categorized by thermal conditions: cold, hot, or polythermal base.
Global Coverage:
- Glaciers cover 10% of the Earth’s surface.
- Combined with ice caps, they contribute to nearly 70% of the world’s fresh water.
Geographical Distribution:
- 91% of glaciers are in Antarctica.
- Greenland houses 8% of the world’s glaciers.
- Overall, glaciers occupy about 10% of the world’s total land area.
Significance of Glaciers:
- Glaciers as Freshwater Reservoirs:
- Approximately three-quarters of Earth’s freshwater is stored in glaciers.
- Glacier ice constitutes the second-largest reservoir of water on Earth and is the primary source of freshwater.
- Ecological Importance:
- Glacial meltwater supports aquatic life in mountainous environments.
- Changes in stream habitat may affect native trout and other species.
- Resource for Humans:
- Glaciers provide fertile soil (glacial till) for agriculture.
- Deposits of sand and gravel are used in construction (concrete and asphalt).
- Climate Impact:
- Melting glacier water affects ocean currents, contributing to sea level rise.
- Polar ice caps, acting as the planet’s “air conditioner,” influence weather dynamics and the jet stream.
- Indicators of Climate Change:
- Glaciers serve as early indicators of climate change, acting as sentinels.
- Water Source for People:
- People in arid climates near mountains rely on glacial meltwater for drinking water.
- Examples include the Ganges and Yangtze rivers.
- Agricultural and Power Generation:
- Farmers in Switzerland’s Rhone Valley have historically irrigated crops with meltwater from glaciers.
- Glacial resources are tapped for hydroelectric power generation in various regions like Norway, central Europe, Canada, New Zealand, and South America.
Causes of Glacier Melting:
- CO2 Emissions:
- Industrial activities, transport, and deforestation contribute to the atmospheric concentration of carbon dioxide and greenhouse gases.
- Increased concentration warms the planet, leading to glacial melting.
- Ocean Warming:
- Oceans, absorbing 90% of Earth’s warmth, impact marine glaciers near the poles and Alaska’s coasts.
- Global warming and temperature increases accelerate glacier melting, surpassing snow accumulation rates.
- Deforestation, Fossil Fuels, and Industry:
- Deforestation, burning fossil fuels, and industrial processes significantly contribute to greenhouse gas emissions.
- These emissions act as catalysts for global warming, directly influencing glacier melt.
- Shifts in Precipitation:
- Changes in precipitation quantity, timing, and form affect glacier extent and thickness.
- Natural Factors:
- Volcanic activity and variations in solar radiation are natural elements influencing glacier melting.
Impact of Melting Glaciers on Climate Change & Human Life:
- Rising Sea Levels:
- Melting glaciers contribute to rising sea levels, posing risks to coastal communities and infrastructure.
- Water Scarcity:
- Glacial melting and retreat can lead to water scarcity, impacting agriculture and various industries.
- Changes in Weather Patterns:
- Melting glaciers influence weather patterns, affecting temperature, precipitation, and phenomena like the destabilization of North Atlantic salinity balance and changes in the Atlantic Meridional Overturning Circulation (AMOC).
- Ecosystem Disruption:
- Melting glaciers disrupt ecosystems, causing changes in biodiversity, food webs, and other ecological systems.
- Potential for Natural Disasters:
- Melting glaciers create the potential for natural disasters such as flash floods or landslides, with catastrophic effects on human life and infrastructure.
- Reduced Albedo Effect:
- Melting glaciers reduce the Earth’s ability to reflect sunlight, leading to increased absorption of solar radiation and warmer temperatures.
The World Meteorological Organization – The Global Climate 2011-2020
- Pro-Glacial Lakes and GLOF Threats:
- The report highlights the rapid growth of pro-glacial lakes.
- Glacier lake outburst floods (GLOFs) pose additional threats to ecosystems and livelihoods.
- GLOF Causes and Concerns:
- Glaciers are susceptible to bursting due to seismic activity, water pressure buildup, and structural weaknesses.
- Climate change, characterized by high temperatures and reduced snowfall, accelerates glacier melting, raising water levels and increasing GLOF risks.
- Glacier and Ice Sheet Loss:
- Global glaciers experienced an unprecedented thinning of about 1 meter/year between 2011 and 2020.
- Greenland and Antarctic ice sheets lost 38% more ice compared to 2001-2010, contributing significantly to rising sea levels.
- Arctic Sea Ice Decline:
- Arctic sea ice continued its decline during the summer melt season, with a mean seasonal minimum extent 30% below the 1981-2010 average.
- Regional Variability and Trends:
- Significant regional variability exists, but the overall trend shows glaciers worldwide becoming smaller.
- Some reference glaciers, crucial for long-term assessments, have already melted away, with winter snow disappearing completely during summer.
- Projected Glacier Disappearance:
- Glaciers on the Rwenzori Mountains and Mount Kenya in Africa are projected to disappear by 2030, along with Kilimanjaro’s glaciers by 2040.
The Way forward:
- Fulfill net-zero emission targets by increasing the use of alternative energy sources like wind and solar power.
- Drastically reduce global CO2 emissions by 45% within the next decade and achieve zero emissions after 2050 to curb climate change.
- Encourage the use of energy-efficient appliances, as seen in initiatives like the Green Housing Scheme by the National Housing Bank.
- Reduce private car usage and greenhouse gas emissions by promoting public transportation.
- Plant more trees to absorb carbon dioxide, contributing to reducing greenhouse gases in the atmosphere.
- Reduce greenhouse gas emissions from landfill and waste disposal by minimizing waste and promoting recycling.
- Combat deforestation to maintain natural carbon sinks, preserving the Earth’s capacity to absorb carbon dioxide.
- Implement practices in agriculture to reduce emissions and preserve water resources, such as conservation tillage.
- Collaborate on international agreements to limit carbon emissions and combat global warming, exemplified by initiatives like the Paris Agreement and the Montreal Protocol.
- Plan and implement measures to adapt to the impacts of melting glaciers, addressing challenges like flooding, water resource management, and infrastructure protection.
- Consider constructing a 100-meter-long dam in front of severely affected glaciers, like the Jakobshavn glacier in Greenland, to contain erosion.
- Explore innovative solutions like collecting water from melted glaciers, desalinating it, and refreezing it into large hexagonal ice blocks.
- Increase glacier thickness by collecting ice from below glaciers through wind-powered pumps and spreading it over upper ice caps. This process strengthens the glacier’s consistency.
References:
The Hindu
World Meteorological Organization
Practice Question
Assess the consequences of melting glaciers and How do these impacts affect human life and ecosystems?