UPSC MainsGEOGRAPHY-PAPER-I202220 Marks
Q12.

Rise of surface temperature brings severe consequences. Elaborate the potential changes and threats associated with it in the world.

How to Approach

This question requires a comprehensive understanding of the consequences of rising surface temperatures, encompassing physical, biological, and socio-economic impacts. The answer should be structured geographically, discussing impacts across different regions. It should also categorize impacts – immediate vs. long-term, reversible vs. irreversible. Focus on providing specific examples and linking them to relevant scientific reports (IPCC, etc.). A balanced approach acknowledging uncertainties is crucial.

Model Answer

0 min read

Introduction

The Earth’s surface temperature has been steadily increasing, primarily due to anthropogenic greenhouse gas emissions. This warming trend, unequivocally established by the Intergovernmental Panel on Climate Change (IPCC), is not merely a statistical anomaly but a catalyst for profound and far-reaching changes across the globe. The consequences extend beyond simply warmer weather, manifesting as altered weather patterns, rising sea levels, and disruptions to ecosystems. Understanding these potential changes and threats is crucial for formulating effective mitigation and adaptation strategies. The global average temperature has already risen by approximately 1.1°C above pre-industrial levels (1850-1900), and further warming is projected under all emission scenarios.

Geographical Variations in Impacts

The impacts of rising surface temperatures are not uniform across the globe. Certain regions are disproportionately vulnerable due to their geographical location, socio-economic conditions, and existing environmental stresses.

1. Polar Regions & High Latitudes

  • Melting Ice & Permafrost: Accelerated melting of glaciers, ice sheets (Greenland, Antarctica), and permafrost releases vast amounts of freshwater into the oceans, contributing to sea-level rise. Permafrost thaw also releases methane, a potent greenhouse gas, creating a positive feedback loop.
  • Impact on Ecosystems: Loss of sea ice threatens polar bear populations and disrupts the entire Arctic food web.
  • Example: The Greenland ice sheet is losing mass at an accelerating rate, contributing significantly to global sea-level rise.

2. Coastal Regions & Small Island Developing States (SIDS)

  • Sea-Level Rise: Thermal expansion of water and melting ice contribute to rising sea levels, threatening coastal communities, infrastructure, and ecosystems (mangroves, coral reefs).
  • Increased Frequency & Intensity of Storm Surges: Warmer ocean temperatures fuel more intense tropical cyclones and storm surges, exacerbating coastal flooding.
  • Saltwater Intrusion: Rising sea levels contaminate freshwater sources, impacting agriculture and drinking water supplies.
  • Example: The Maldives, a low-lying island nation, faces an existential threat from sea-level rise.

3. Arid & Semi-Arid Regions

  • Desertification: Increased evaporation rates and altered rainfall patterns exacerbate desertification, leading to land degradation and reduced agricultural productivity.
  • Water Scarcity: Higher temperatures increase water demand while reducing water availability, leading to severe water stress.
  • Heatwaves: More frequent and intense heatwaves pose a significant threat to human health and livestock.
  • Example: The Sahel region of Africa is experiencing prolonged droughts and desertification, leading to food insecurity and displacement.

4. Temperate Regions

  • Changes in Agricultural Productivity: Altered growing seasons, increased pest outbreaks, and water stress impact agricultural yields.
  • Increased Frequency of Extreme Weather Events: Heatwaves, droughts, floods, and wildfires become more common and intense.
  • Shifts in Species Distribution: Species migrate to cooler regions, disrupting ecosystems and potentially leading to biodiversity loss.
  • Example: California is experiencing more frequent and severe wildfires due to prolonged droughts and high temperatures.

Specific Threats Associated with Rising Surface Temperature

Threat Description Impact
Food Security Reduced crop yields, livestock productivity, and fisheries due to climate change impacts. Increased food prices, malnutrition, and famine.
Water Security Decreased water availability, increased competition for water resources, and saltwater intrusion. Water scarcity, conflicts over water, and health problems.
Human Health Increased heat-related illnesses, spread of vector-borne diseases, and respiratory problems due to air pollution. Increased morbidity and mortality rates.
Biodiversity Loss Habitat loss, species extinction, and disruption of ecosystems. Loss of ecosystem services and reduced resilience to climate change.
Economic Impacts Damage to infrastructure, reduced agricultural productivity, and increased disaster relief costs. Slower economic growth and increased poverty.

Irreversible Changes & Tipping Points: Beyond certain temperature thresholds, some changes may become irreversible, such as the collapse of major ice sheets or the dieback of the Amazon rainforest. These "tipping points" could trigger cascading effects with potentially catastrophic consequences.

Conclusion

Rising surface temperatures pose a multifaceted and escalating threat to the world, impacting every region and sector. The consequences range from immediate disruptions to long-term, potentially irreversible changes. Addressing this challenge requires a concerted global effort to mitigate greenhouse gas emissions through transitioning to renewable energy sources, improving energy efficiency, and promoting sustainable land use practices. Simultaneously, adaptation measures are crucial to build resilience and minimize the impacts of climate change, particularly for vulnerable populations and ecosystems. A proactive and collaborative approach is essential to safeguard the planet for future generations.

Answer Length

This is a comprehensive model answer for learning purposes and may exceed the word limit. In the exam, always adhere to the prescribed word count.

Additional Resources

Key Definitions

Thermal Expansion
The tendency of matter to change in volume in response to changes in temperature. When a substance is heated, its particles move more and thus maintain a greater average separation. In the context of climate change, thermal expansion refers to the increase in volume of water as it warms, contributing to sea-level rise.
Albedo Effect
The albedo effect refers to the measure of how much light that hits a surface is reflected without being absorbed. Surfaces with high albedo (like ice and snow) reflect more sunlight, while surfaces with low albedo (like forests and oceans) absorb more sunlight. Melting ice and snow reduce Earth’s albedo, leading to increased absorption of solar radiation and further warming.

Key Statistics

The IPCC Sixth Assessment Report (AR6) states that global surface temperature was 1.09 [0.95 to 1.20] °C higher in 2011–2020 than 1850–1900.

Source: IPCC AR6 (2021)

According to the World Meteorological Organization (WMO), the past eight years (2015-2022) were the warmest on record.

Source: WMO, 2023

Examples

The Great Barrier Reef Bleaching

The Great Barrier Reef in Australia has experienced several mass coral bleaching events in recent years (2016, 2017, 2020, 2022) due to rising ocean temperatures. Coral bleaching occurs when corals expel the algae living in their tissues, causing them to turn white and become more susceptible to disease and death. This has devastating consequences for the reef ecosystem and the tourism industry.

Frequently Asked Questions

What is the difference between climate change and global warming?

Global warming refers specifically to the increase in Earth's average surface temperature, while climate change encompasses broader changes to the Earth's climate system, including temperature, precipitation, sea level, and extreme weather events. Global warming is one aspect of climate change.

Topics Covered

GeographyEnvironmentClimate ChangeGlobal WarmingEnvironmental Hazards