What are the causes and consequences of global warming and climate change? Explain the approaches to deal with global warming.

Causes of Global Warming and Climate Change

Global warming and climate change are driven by both natural and anthropogenic (human-induced) factors, with the latter being the dominant cause of the rapid warming observed since the Industrial Revolution.

1. Anthropogenic Causes

• Burning of Fossil Fuels: The combustion of coal, oil, and natural gas for electricity generation, transportation, and industrial processes releases vast amounts of carbon dioxide (CO₂) and other greenhouse gases into the atmosphere. This is identified as the primary driver of global warming.
• Deforestation: Forests act as vital carbon sinks, absorbing CO₂ from the atmosphere. Large-scale deforestation for agriculture, logging, and urbanization reduces the planet's capacity to absorb CO₂, leading to an increased concentration of atmospheric CO₂.
• Industrial Processes: Various industrial activities release GHGs like methane (CH₄) from oil and gas production, nitrous oxide (N₂O) from industrial farming, and fluorinated gases from refrigerants and solvents, all of which have high global warming potential.
• Agriculture and Livestock: Agricultural practices, such as the use of synthetic fertilizers, contribute to N₂O emissions. Livestock farming, particularly ruminants, produces significant amounts of methane through enteric fermentation.
• Waste Management: Landfills generate methane as organic waste decomposes in anaerobic conditions.

2. Natural Factors

While human activities are the primary cause of current warming, natural factors can also influence climate:

• Volcanic Activity: Large volcanic eruptions can release aerosols that temporarily cool the Earth by reflecting sunlight. However, they also emit CO₂, though their long-term contribution to atmospheric CO₂ is minor compared to human emissions.
• Solar Radiation Variations: Fluctuations in the sun's energy output can influence Earth's climate. However, these variations are not significant enough to explain the rapid warming observed over the past century.
• Earth's Orbital Changes (Milankovitch Cycles): Changes in the Earth's orbit and axial tilt influence the distribution of solar radiation, leading to long-term climate shifts (ice ages and interglacial periods) over thousands of years. These operate on timescales far too long to explain current rapid warming.

Consequences of Global Warming and Climate Change

The consequences of global warming and climate change are far-reaching, impacting natural ecosystems, human societies, and economies globally. The IPCC reports highlight that these impacts are already widespread and intensifying.

1. Environmental Consequences

• Rising Global Temperatures: The most direct impact is the increase in Earth's average temperature, leading to more frequent and intense heatwaves.
• Melting Ice Caps and Glaciers: Accelerated melting of polar ice caps and glaciers, particularly in the Arctic and Antarctic, contributes significantly to rising sea levels.
• Sea Level Rise: As ice melts and oceans expand due to warming, sea levels rise, threatening low-lying coastal areas, small island nations, and increasing coastal erosion and flooding. The rate of sea level rise increased from 1.3 mm/year (1901-1971) to 3.7 mm/year (2006-2018).
• Extreme Weather Events: Increased frequency and intensity of extreme weather events such as hurricanes, cyclones, floods, droughts, and wildfires.
• Ocean Acidification: Oceans absorb a significant portion of atmospheric CO₂, leading to a decrease in pH, which harms marine life, particularly organisms with shells and skeletons like corals and shellfish.
• Biodiversity Loss: Climate change disrupts ecosystems and habitats, forcing species to migrate or adapt. Many species cannot cope with the rapid pace of change, leading to habitat destruction and increased extinction rates. For example, coral reefs are highly sensitive to temperature changes.

2. Socio-Economic Consequences

• Food Insecurity: Changes in temperature and precipitation patterns, along with increased extreme weather events, affect agricultural productivity, crop yields, and livestock, leading to food shortages and price volatility.
• Water Scarcity: Altered rainfall patterns and melting glaciers impact freshwater availability, exacerbating water stress in many regions.
• Health Impacts: Increased heatwaves lead to heat-related illnesses and mortality. Changes in climate patterns can also expand the geographic range of vector-borne diseases (e.g., malaria, dengue) and waterborne diseases (e.g., cholera).
• Displacement and Migration: Sea-level rise, extreme weather events, and resource scarcity can force populations to relocate, leading to climate migration and associated social and economic challenges.
• Economic Losses: Damages to infrastructure, agriculture, and property from extreme weather events, coupled with impacts on resource-dependent industries, result in significant economic losses.

Approaches to Deal with Global Warming

Addressing global warming requires a multi-pronged approach encompassing mitigation (reducing GHG emissions) and adaptation (adjusting to unavoidable impacts). International cooperation, national policies, technological innovations, and individual actions are all crucial.

1. Mitigation Strategies

Mitigation focuses on reducing the sources of greenhouse gases or enhancing their sinks.

• Transition to Renewable Energy:
  • Solar and Wind Power: Rapid investment and adoption of renewable energy sources like solar, wind, and hydropower to replace fossil fuels. India's installed renewable energy capacity increased by 165% in the last decade, reaching 203.1 GW in 2024.
  • Nuclear Energy: Utilizing nuclear power as a low-carbon energy source.
  • Green Hydrogen: Promoting the production and use of green hydrogen to decarbonize hard-to-abate sectors. India aims for 5 million tonnes of green hydrogen production annually by 2030.
• Energy Efficiency and Conservation:
  • Implementing energy-efficient technologies in industries, buildings, and transportation.
  • Promoting smart grids and energy-plus buildings.
• Carbon Sequestration and Sinks:
  • Afforestation and Reforestation: Planting new trees and restoring degraded forests to enhance natural carbon sinks. Schemes like India's Green India Mission and Nagar Van Yojana aim to increase forest cover.
  • Carbon Capture, Utilization, and Storage (CCUS): Technologies that capture CO₂ emissions from industrial sources and power plants, and store them underground or convert them into useful products.
  • Soil Carbon Sequestration: Implementing sustainable agricultural practices that increase carbon content in soil.
• Sustainable Transportation:
  • Promoting public transportation, electric vehicles, and active mobility (walking, cycling).
  • Developing efficient urban planning to reduce travel demand.
• Waste Management:
  • Reducing, reusing, and recycling waste to minimize landfill emissions.
  • Improving waste-to-energy technologies.
• Policy and Regulatory Frameworks:
  • Carbon Pricing: Implementing carbon taxes or emissions trading schemes to internalize the cost of carbon emissions. India is preparing to launch its national compliance carbon market by mid-2026 under the Carbon Credit Trading Scheme (CCTS).
  • International Agreements: Adherence to global frameworks like the Paris Agreement, which aims to limit global warming to well below 2°C, preferably to 1.5°C.

2. Adaptation Strategies

Adaptation involves adjusting to actual or expected future climate. It aims to reduce vulnerability to the harmful effects of climate change.

• Climate-Resilient Infrastructure:
  • Building infrastructure (e.g., seawalls, resilient housing, improved drainage systems) to withstand extreme weather events and rising sea levels.
  • Developing early warning systems for climate-related hazards.
• Sustainable Water Management:
  • Implementing rainwater harvesting, efficient irrigation techniques, and desalination to address water scarcity.
  • Protecting and restoring wetlands to improve water retention and flood control.
• Climate-Smart Agriculture:
  • Developing drought-resistant crops and adopting farming practices that enhance resilience to changing climatic conditions.
  • Diversifying crops and livestock to reduce vulnerability.
• Ecosystem-Based Adaptation:
  • Protecting and restoring natural ecosystems (e.g., mangroves, coral reefs, forests) that provide natural defenses against climate impacts.
• Public Health Measures:
  • Strengthening healthcare systems to manage heat-related illnesses and vector-borne diseases.
  • Implementing public awareness campaigns on climate health risks.
• Capacity Building and Knowledge Sharing:
  • Investing in research and development to understand regional climate impacts and develop localized solutions.
  • Building human and institutional capacity to plan and implement climate action.

3. Global and National Initiatives

International cooperation and national policies are vital for a concerted effort against global warming.

Initiative Type	Description and Examples
International Frameworks	United Nations Framework Convention on Climate Change (UNFCCC): Provides the overarching international treaty. Kyoto Protocol (1997): Set legally binding emission reduction targets for developed countries. Paris Agreement (2015): A global agreement aiming to limit warming to well below 2°C, with a target of 1.5°C. Nations submit Nationally Determined Contributions (NDCs). Green Climate Fund: A financial mechanism to assist developing countries in adaptation and mitigation practices.
India's Initiatives	National Action Plan on Climate Change (NAPCC) (2008): Comprises eight (now nine) national missions focusing on solar energy, enhanced energy efficiency, sustainable habitat, water, sustaining the Himalayan ecosystem, green India, sustainable agriculture, strategic knowledge for climate change, and most recently, the National Bio-energy Mission. Panchamrita (COP26, Glasgow): India's five-pronged climate action plan to achieve net-zero emissions by 2070, including 500 GW non-fossil energy capacity by 2030, 50% energy from renewables by 2030, and reducing carbon intensity by 45% by 2030. National Green Hydrogen Mission: Aims to make India a global hub for green hydrogen production and export by 2030. Energy Conservation (Amendment) Bill: Sets in motion the creation of a domestic carbon market. Lifestyle for Environment (LiFE) Movement: Promotes sustainable lifestyles and mindful consumption.