Impact of Marine Heatwaves

Question

Key Highlights on the Impact of Marine Heatwaves on Alaska's Seabird Population

Why in News

• A study reports the 2014-2016 Pacific marine heatwave as the cause of the largest documented vertebrate die-off linked to ocean warming, resulting in the death of four million common murres (Uria aalge), a seabird species native to Alaska.

Key Findings

1. Significant Mortality Event:

   • Approximately 52-78% decline in population across 13 murre colonies.
   • Loss of four million birds within two years (2014-2016).
   • Decline represents the largest documented wildlife mortality event in modern history related to climate change.

2. Impact of Marine Heatwaves:

   • Marine heatwaves are intense, prolonged ocean warming events driven by climate change.
   • Consequences include:
     • Mass mortality of habitat-forming species (kelps, corals).
     • Trophic effects disrupting ecosystem productivity.
     • Food shortages for top predators due to displacement of lower-trophic species.

3. Long-Term Effects:

   • No population recovery noted from 2016 to 2022, indicating a possible ecosystem shift.
   • Reduced ecosystem capacity to support historical seabird populations.

4. New Threshold of Response:

   • The pronounced population decline signals a new threshold for climate impacts on upper trophic predators, underscoring the urgency of addressing global warming.

Implications

• Highlights the rapid and intense impact of climate change on marine ecosystems.
• Suggests potential irreversible ecosystem changes, challenging the resilience of species like seabirds.

Key Terms

• Marine Heatwaves: Periods of extreme ocean warming with severe ecological consequences.
• Trophic Effects: Disruptions in the food web impacting energy flow across different levels.

Potential Questions for UPSC Preparation

Prelims MCQ:

1. Consider the following statements regarding marine heatwaves:

   • They are natural phenomena unrelated to climate change.
   • They cause trophic disruptions and mass mortality of marine species.
   • Their frequency is expected to decrease in the coming decades.
   • Marine heatwaves are linked to reduced ecosystem productivity.

   Which of the above statements is/are correct?

   • (a) 1 and 3 only
   • (b) 2 and 4 only
   • (c) 2, 3, and 4 only
   • (d) 1, 2, and 4 only
     Answer: (b) 2 and 4 only

Mains Question:

• Discuss the impact of marine heatwaves on marine biodiversity, focusing on key habitat-forming species and top predators. What measures can be taken to mitigate such impacts?
• 

Answer 1

Murres (Uria aalge) Overview

Introduction

• Common Murres (Uria aalge), also known as Common Guillemots in Europe, are seabirds belonging to the auk family (Alcidae).
• Found in the Northern Hemisphere, they are known for their dense breeding colonies on rocky cliffs and islands.

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Physical Features

1. Size: Medium-sized seabirds with a body length of 38–45 cm and a wingspan of 61–73 cm.
2. Plumage:
   • Black or dark brown on the head, back, and wings.
   • White underparts.
   • During non-breeding seasons, their face may develop a white streak.
3. Bill: Thin, pointed, and black in color, adapted for catching small fish.

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Habitat

• Prefer cold oceanic waters.
• Nest on coastal cliffs, offshore islands, and steep rocky ledges.

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Distribution

• Found across the North Atlantic and North Pacific Oceans.
• In North America: Concentrated along Alaska, Canada, and the Pacific Northwest.
• Migratory, often traveling long distances to feed and breed.

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Behavior

1. Feeding:

   • Diet primarily consists of small fish like herring, capelin, and sand lance.
   • Occasionally feed on squid and crustaceans.
   • Dive up to 100 meters to hunt, using their wings for propulsion.

2. Breeding:

   • Form large colonies during the breeding season (spring-summer).
   • Lay a single, pear-shaped egg directly on bare rock; the shape prevents the egg from rolling off ledges.
   • Both parents share responsibilities of incubation and chick-rearing.

3. Vocalization: Emit low growling calls in colonies, mainly for communication between mates and chicks.

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Ecological Importance

• As upper trophic predators, murres are key indicators of marine ecosystem health.
• Changes in fish availability and water temperatures due to climate change directly affect their survival and reproduction.

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Threats

1. Climate Change:

   • Marine heatwaves causing food shortages.
   • Habitat loss due to warming and ocean acidification.

2. Pollution:

   • Oil spills and marine plastic affect their survival.

3. Bycatch:

   • Accidental entanglement in fishing nets.

4. Predation:

   • Vulnerable to predators like gulls, foxes, and invasive species during breeding.

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Conservation

1. Legal Protections:

   • Covered under the Migratory Bird Treaty Act in the U.S.
   • Listed in international conservation agreements.

2. Monitoring Efforts:

   • Population counts to assess health and recovery.
   • Research on marine ecosystem impacts.

3. Climate Action:

   • Reducing greenhouse gas emissions to mitigate marine heatwaves and habitat shifts.

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Interesting Facts

• Murre eggs are highly resilient, with tough shells to withstand rough surfaces.
• During their first flight, chicks leap off cliffs into the sea, guided by the calls of their parents.

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Relevance for Current Affairs:
The 2014-2016 Pacific marine heatwave caused a 52-78% population decline in murres, underlining the urgent need to address climate impacts on marine biodiversity.

Answer 2

Marine Heatwaves: A Comprehensive Overview

Introduction

Marine heatwaves (MHWs) are prolonged periods of abnormally high sea surface temperatures (SSTs) in a specific region, often persisting for weeks or months. They are increasingly linked to climate change and have profound ecological, social, and economic impacts.

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Definition

• Marine Heatwave: A significant, prolonged deviation in sea surface temperature exceeding the seasonal average, lasting five or more days.
• Example: The 2014-2016 Pacific Marine Heatwave (also known as "The Blob") caused extensive damage to marine ecosystems, including the mass die-off of seabirds like the common murre (Uria aalge).

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Causes

1. Climate Change:

   • Greenhouse gas emissions intensify ocean warming.
   • Sea surface temperatures rise beyond natural variability.

2. Atmospheric Conditions:

   • Persistent high-pressure systems reduce wind-driven mixing of warm surface water with cooler deep water.

3. Ocean Currents:

   • Alterations in oceanic circulation patterns (e.g., El Niño events) contribute to heatwave formation.

4. Reduced Albedo Effect:

   • Decline in sea ice and reflective surfaces increases absorption of solar radiation.

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Characteristics

1. Intensity: Degrees of temperature anomaly above the norm.
2. Duration: Lasting from several days to years (e.g., multi-year heatwaves).
3. Spatial Extent: Can span hundreds to thousands of kilometers.

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Ecological Impacts

1. Marine Species:

   • Mass mortality of species like corals, kelps, and seabirds.
   • Displacement of fish stocks affecting ecosystems and fisheries.

2. Habitat Alteration:

   • Destruction of habitat-forming species (e.g., coral bleaching).
   • Long-term changes in marine biodiversity.

3. Trophic Effects:

   • Disruptions in food chains; decline in prey availability for top predators.

4. Ecosystem Shifts:

   • Permanent changes in marine ecosystems, reducing productivity and biodiversity.

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Examples of Marine Heatwaves

1. The Blob (2014-2016):
   • Affected the Pacific Ocean; associated with the mass die-off of seabirds, fish, and marine mammals.
2. Great Barrier Reef (2016, 2017):
   • Coral bleaching events caused by back-to-back heatwaves.
3. Mediterranean Heatwave (2022):
   • Record-breaking temperatures, impacting fisheries and tourism.

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Economic and Social Impacts

1. Fisheries:

   • Loss of fish stocks affecting livelihoods and economies.
   • Example: Decline in Alaska's salmon and cod fisheries due to altered habitats.

2. Tourism:

   • Degradation of marine ecosystems like coral reefs affects tourism revenue.

3. Food Security:

   • Reduced fish availability impacts global protein sources.

4. Coastal Communities:

   • Increased vulnerability to marine resource changes and extreme weather.

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Mitigation and Adaptation Strategies

1. Global Action on Climate Change:

   • Reduction of greenhouse gas emissions.
   • Implementation of international agreements like the Paris Agreement.

2. Marine Protected Areas (MPAs):

   • Conservation of biodiversity hotspots to enhance resilience.

3. Monitoring and Forecasting:

   • Real-time tracking of sea surface temperature anomalies.
   • Tools like NOAA’s Marine Heatwave Tracker.

4. Ecosystem Restoration:

   • Active restoration of degraded habitats like coral reefs and kelp forests.

5. Policy Interventions:

   • Regulation of fishing activities during MHWs to protect vulnerable species.

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Key Takeaways

• Marine heatwaves are among the most severe manifestations of climate change, impacting marine ecosystems, economies, and communities.
• The 2014-2016 Pacific marine heatwave highlighted the fragility of oceanic biodiversity and the cascading effects of such events.
• Mitigation and adaptation strategies are essential to safeguard marine ecosystems and human livelihoods.

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Relevant Questions for UPSC Preparation

Prelims MCQ:

1. Which of the following statements about marine heatwaves is/are correct?

   • They are characterized by prolonged periods of above-average sea surface temperatures.
   • They are primarily caused by volcanic eruptions.
   • They can lead to mass mortality events in marine species.
   • Marine heatwaves have no economic impact.

   Select the correct option:

   • (a) 1 and 3 only
   • (b) 1, 2, and 3 only
   • (c) 1, 3, and 4 only
   • (d) 1, 2, 3, and 4

   Answer: (a) 1 and 3 only

Mains Question:

• Discuss the causes and ecological impacts of marine heatwaves. How can global and local actions mitigate their effects on marine ecosystems?

Comments

International and India's Efforts to Reduce Heatwaves

Heatwaves, both marine and terrestrial, are a growing threat due to climate change. Efforts at the international and national levels focus on mitigation, adaptation, and resilience-building to address their impacts.

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International Efforts

1. Global Agreements and Frameworks

• Paris Agreement (2015):

  • Aims to limit global temperature rise to below 2°C, ideally 1.5°C, to reduce extreme weather events, including heatwaves.
  • Focuses on emission reductions, climate adaptation, and financial support for developing countries.

• Sendai Framework for Disaster Risk Reduction (2015-2030):

  • Focuses on reducing disaster risks, including heatwaves, through preparedness, mitigation, and resilience-building strategies.

• UN Sustainable Development Goals (SDGs):

  • Goals 13 (Climate Action), 14 (Life Below Water), and 15 (Life on Land) address the root causes and impacts of heatwaves.

2. Scientific Monitoring and Research

• IPCC Reports:

  • Provide critical assessments of climate change impacts, including heatwaves, and recommend mitigation strategies.

• Global Heat Health Information Network (GHHIN):

  • A collaboration of WHO and WMO to provide scientific data and guidance for managing heat-health risks.

• Marine Heatwave Tracker:

  • Developed by NOAA, this tool monitors marine heatwave occurrences and provides early warnings.

3. Regional Initiatives

• European Heatwave Action Plans:

  • Focus on vulnerable populations during terrestrial heatwaves through early warnings and health advisories.

• Coral Reef Restoration Projects:

  • Efforts like the Coral Triangle Initiative aim to restore marine biodiversity and mitigate marine heatwave effects.

• Green Climate Fund (GCF):

  • Supports climate-resilient infrastructure and renewable energy projects globally to mitigate heatwave impacts.

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India's Efforts

1. Policy and Action Plans

• National Action Plan on Climate Change (NAPCC):

  • Includes eight missions focusing on renewable energy, sustainable agriculture, water management, and ecosystem conservation to combat climate change.

• State Action Plans on Climate Change (SAPCCs):

  • Customized state-level strategies aligned with the NAPCC to address local heatwave challenges.

• National Disaster Management Authority (NDMA) Guidelines on Heatwaves (2016):

  • Provides comprehensive guidance on managing heatwave impacts, including early warnings, public awareness, and health management.

2. Heatwave Management Initiatives

• Heat Action Plans (HAPs):
  • Initiated in Ahmedabad in 2013, now adopted by several states and cities.
  • Focus on:
    • Early warning systems.
    • Community awareness campaigns.
    • Training healthcare professionals to treat heat-related illnesses.

3. Renewable Energy Transition

• National Solar Mission:

  • Part of NAPCC, aiming for a transition to renewable energy to reduce greenhouse gas emissions and mitigate global warming.

• Promotion of Electric Vehicles:

  • Under the Faster Adoption and Manufacturing of Hybrid and Electric Vehicles (FAME) scheme.

4. Ecosystem-Based Adaptation

• Afforestation Programs:

  • Initiatives like CAMPA (Compensatory Afforestation Fund Management and Planning Authority) aim to increase green cover to mitigate urban heat islands.

• Water Management:

  • Programs like Jal Shakti Abhiyan focus on water conservation, essential for reducing the vulnerability of rural communities to heatwaves.

5. Marine Heatwave Mitigation

• Coastal Regulation Zone (CRZ) Rules:

  • Protect coastal ecosystems, including mangroves and corals, which act as natural buffers against heatwave impacts.

• Mangrove Restoration Projects:

  • Efforts to restore mangroves in coastal states like Maharashtra and Odisha.

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Challenges

• Global:
  • Insufficient climate finance for developing nations.
  • Lack of coordination among countries for effective implementation.
• India:
  • Limited resources for implementing state action plans.
  • High dependence on coal and other fossil fuels.

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Way Forward

1. Strengthen Global Cooperation:

   • Enhance commitments under the Paris Agreement and provide financial and technological support to vulnerable countries.

2. Local Capacity Building:

   • Expand HAPs to rural areas in India and improve urban planning to mitigate heat islands.

3. Community Engagement:

   • Promote public awareness campaigns for better preparedness and adaptation to heatwave conditions.

4. Research and Innovation:

   • Invest in climate-resilient infrastructure and renewable technologies to mitigate the root causes of heatwaves.

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Relevant Questions for UPSC Preparation

Prelims MCQ:

1. Consider the following statements:

   • The Sendai Framework exclusively addresses disaster risks caused by natural events.
   • Heat Action Plans (HAPs) in India were first implemented in Ahmedabad.
   • Paris Agreement focuses solely on reducing carbon emissions.

   Which of the above statements is/are correct?

   • (a) 1 and 2 only
   • (b) 2 only
   • (c) 2 and 3 only
   • (d) 1, 2, and 3

   Answer: (b) 2 only

Mains Question:

• "Heatwaves, both marine and terrestrial, are a growing challenge due to climate change." Discuss the international and India's efforts to mitigate their impacts, and suggest measures for improving preparedness and resilience.

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Terrestrial Heatwaves: A Comprehensive Overview

Introduction

Terrestrial heatwaves are prolonged periods of excessive heat, often accompanied by high humidity, with temperatures significantly above the seasonal average. They are among the most devastating climate-related disasters, impacting ecosystems, human health, agriculture, and infrastructure.

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Definition

• Heatwave (As per India Meteorological Department):
  A condition when the maximum temperature exceeds:
  • 40°C in plains.
  • 37°C in coastal regions.
  • 30°C in hilly regions.

Additionally, if temperatures are 4.5°C to 6.4°C above normal, it is classified as a heatwave. If the deviation exceeds 6.4°C, it is an extreme heatwave.

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Causes of Terrestrial Heatwaves

1. Global Warming:
   • Increased greenhouse gas concentrations elevate Earth's average temperature.
2. Atmospheric Pressure Patterns:
   • High-pressure systems trap heat in the lower atmosphere, causing temperatures to soar.
3. Urban Heat Islands:
   • Urban areas with reduced vegetation and high concrete concentration trap heat, amplifying its intensity.
4. Deforestation and Land Use Changes:
   • Loss of vegetation reduces surface cooling, intensifying heatwaves.
5. El Niño Effect:
   • Associated with drier conditions and elevated temperatures over land.

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Characteristics

1. Duration:

   • Ranges from days to weeks.
   • Example: The 2015 Indian heatwave lasted for over a week, causing significant fatalities.

2. Intensity:

   • Measured by temperature deviation above seasonal averages.

3. Geographic Extent:

   • Affects large regions, often entire states or countries.

4. Frequency:

   • Increasing due to climate change, with more intense and frequent events observed globally.

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Impacts

1. Human Health

• Heat-related illnesses (heat exhaustion, heatstroke).
• Aggravation of pre-existing conditions like cardiovascular and respiratory diseases.
• Increased mortality, especially among vulnerable populations (elderly, children, outdoor workers).

2. Agriculture

• Reduced crop yields due to heat stress (e.g., wheat, rice, and maize).
• Soil moisture depletion, leading to droughts.
• Livestock health and productivity decline.

3. Water Resources

• Increased evaporation rates reduce water availability.
• Stress on drinking water supplies, especially in rural areas.

4. Ecosystems and Biodiversity

• Disruption of plant and animal life cycles.
• Increased forest fires due to dry conditions.
• Migration or extinction of heat-intolerant species.

5. Economy and Infrastructure

• Energy demand surges for cooling, straining power grids.
• Damages to roads, railways, and buildings due to thermal expansion.
• Reduced worker productivity, especially in outdoor jobs.

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Examples of Major Terrestrial Heatwaves

1. India (2015):

   • Over 2,000 deaths reported, especially in Andhra Pradesh and Telangana.

2. Europe (2003):

   • Over 70,000 fatalities, primarily among the elderly.

3. North America (2021):

   • Record-breaking temperatures in the Pacific Northwest; deaths and wildfires.

4. Australia (2019):

   • Severe heatwave causing extensive bushfires.

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India's Efforts to Combat Terrestrial Heatwaves

1. National Action Plans:

   • Heat Action Plans (HAPs):
     • Initiated in Ahmedabad (2013) and adopted by several cities and states.
     • Components:
       • Early warning systems.
       • Public awareness campaigns.
       • Cooling centers and water stations.

2. NDMA Guidelines (2016):

   • Comprehensive guidelines for managing heatwaves:
     • Risk assessment.
     • Health advisories and capacity building.

3. Urban Planning:

   • Promoting green buildings and urban forests to reduce heat islands.

4. Afforestation Programs:

   • Efforts under CAMPA to increase green cover and mitigate temperature rise.

5. Water Conservation:

   • Initiatives like Jal Shakti Abhiyan to ensure water availability during heatwaves.

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Global Efforts

1. Sendai Framework for Disaster Risk Reduction:

   • Emphasizes reducing heatwave impacts through preparedness and resilience-building.

2. Urban Heat Island Mitigation:

   • Projects in cities like Paris and Tokyo focus on increasing urban greenery and reflective building materials.

3. Early Warning Systems:

   • Use of AI and satellite data to predict and monitor heatwave conditions globally.

4. WHO Heat-Health Action Plans:

   • Focus on public health measures to reduce heat-related illnesses and deaths.

5. Renewable Energy Transition:

   • Global efforts to reduce fossil fuel dependency and curb climate change.

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Way Forward

1. Adaptation Measures:

   • Develop region-specific Heat Action Plans.
   • Promote traditional cooling methods like shaded verandas and ventilated homes.

2. Mitigation Measures:

   • Reduce greenhouse gas emissions through renewable energy and afforestation.

3. Public Awareness:

   • Disseminate heatwave warnings and health advisories effectively.

4. Research and Monitoring:

   • Invest in technologies for real-time monitoring and forecasting.

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Relevant Questions for UPSC Preparation

Prelims MCQ:

1. Consider the following statements regarding heatwaves:

   • Heatwaves are defined when the maximum temperature exceeds 35°C in plains.
   • Urban heat islands amplify the effects of heatwaves.
   • The first Heat Action Plan in India was implemented in Ahmedabad.

   Which of the above statements is/are correct?

   • (a) 1 and 2 only
   • (b) 2 and 3 only
   • (c) 1, 2, and 3
   • (d) 3 only

   Answer: (b) 2 and 3 only

Mains Question:

• Discuss the causes and impacts of terrestrial heatwaves in India. Suggest mitigation and adaptation strategies to minimize their adverse effects.