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Subject: Geography

  • How ACs catch fire, and the role temperature plays in it

    Why in the News?

    A major fire in a residential apartment in Delhi’s Dwarka area, allegedly triggered by an AC blast, led to fatalities during an intense heatwave. The incident has drawn attention to the rising number of air-conditioner fire accidents during summers, as prolonged AC usage and extreme temperatures increase overheating and electrical risks.

    What are Air Conditioners (ACs)?

    Air conditioners (ACs) are electrical cooling devices that reduce indoor temperature and humidity by removing heat from enclosed spaces and releasing it outside through a refrigeration cycle. 

    They work using components such as a compressor, condenser, evaporator, and refrigerant gas to maintain comfortable room temperatures, especially during extreme summers and heatwaves.

    Why are AC fire incidents increasing during extreme summers?

    1. Heatwave Conditions: Rising ambient temperatures force ACs to operate continuously for longer hours, increasing thermal stress on internal components.
    2. Higher Cooling Load: Elevated outdoor temperatures reduce cooling efficiency, compelling compressors to work harder and consume more electricity.
    3. Urban Dependence: Increased AC penetration in cities raises cumulative electricity demand and appliance stress, particularly in densely populated apartments.
    4. Climate Linkage: More frequent and intense heatwaves have expanded cooling requirements, converting household cooling devices into a potential urban safety concern.
    5. Delhi Case Example: The Dwarka apartment fire allegedly linked to an AC blast highlighted the severe consequences of overheating in enclosed residential spaces.

    How do air conditioners catch fire?

    1. Overheating: Continuous operation during peak summers causes excessive heat generation in internal components, wiring, and insulation systems.
    2. Insulation Damage: Excessive heat degrades insulation materials inside the AC, exposing electrical parts and increasing ignition risk.
    3. Short Circuits: Electrical current may flow through unintended paths due to damaged wiring, overheating, or loose electrical connections, generating sparks capable of igniting combustible materials.
    4. Electrical Overload: Excessive current flow places stress on circuits and electrical systems, increasing fire probability.
    5. Faulty Components: Damaged compressors, malfunctioning parts, and ageing electrical systems increase operational risks.
    6. Indoor Unit Vulnerability: While external compressor units generally overheat, indoor AC units pose higher fire risks because electrical sparks generated internally can ignite surrounding household materials.

    Major causes of AC overheating

    How do blocked filters increase fire risk?

    1. Blocked Air Filters: Dust accumulation restricts airflow, forcing the AC to work harder and causing overheating.
    2. Cooling Inefficiency: Reduced ventilation decreases heat dissipation capacity and elevates internal temperature.

    How do electrical faults trigger AC fires?

    1. Short Circuits: Loose wiring or damaged electrical circuits create sparks that may ignite nearby combustible materials.
    2. Voltage Fluctuation: Irregular power supply damages sensitive AC components and accelerates system wear.
    3. Poor Wiring Quality: Faulty or substandard wiring increases overheating probability.

    Why are gas leaks dangerous in AC systems?

    1. Refrigerant Leakage: Leakage creates pressure imbalances and operational stress that may increase fire vulnerability.
    2. Compressor Stress: Improper refrigerant circulation forces compressors to overwork and malfunction.

    Why does prolonged usage increase overheating?

    1. Extended Operation: Running ACs continuously for long durations during summers overheats internal components.
    2. Component Fatigue: Persistent use accelerates wear and malfunction in motors, compressors, and circuit boards.

    Are inverter ACs safer than non-inverter ACs?

    1. Inverter Technology: Inverter AC compressors regulate speed gradually according to room temperature rather than repeatedly switching on and off.
    2. Reduced Stress: Continuous speed modulation lowers operational pressure on electrical components.
    3. Energy Efficiency: Inverter systems consume less power during sustained operation.
    4. Non-Inverter Limitation: Conventional ACs repeatedly restart compressors at full speed, increasing mechanical stress and overheating risks.
    5. Conditional Safety: Inverter ACs are relatively safer but remain vulnerable to poor installation, electrical faults, voltage fluctuation, and lack of maintenance.

    What are the warning signs of an unsafe AC system?

    1. Frequent Tripping: Repeated circuit breaker shutdown indicates excessive load or electrical faults.
    2. Unusual Noise: Buzzing or abnormal sounds may indicate compressor or motor malfunction.
    3. Burning Smell: Smell from wiring or components signals overheating.
    4. Irregular Cooling: Reduced cooling performance may indicate blocked filters, gas leakage, or compressor problems.
    5. Frequent On-Off Cycling: Repeated switching suggests electrical instability or malfunction.

    Safety measures that can reduce AC fire incidents

    How can maintenance reduce overheating risks?

    1. Regular Servicing: Ensures cleaning, component inspection, refrigerant checks, and early detection of faults.
    2. Filter Cleaning: Maintains airflow and prevents internal overheating.
    3. Dust Removal: Cleaning indoor and outdoor units reduces heat accumulation.

    How does electrical protection improve safety?

    1. Circuit Breakers: Ensures automatic disconnection during overload or short circuits.
    2. Dedicated Wiring: Supports safe electricity flow and reduces overloading.
    3. Voltage Stabiliser: Protects AC units from frequent power fluctuations.

    What temperature practices improve efficiency and safety?

    1. Optimal Temperature Setting: Maintaining temperatures between 24-26°C reduces compressor burden and energy consumption.
    2. Controlled Usage: Prevents prolonged continuous operation during extreme heat.

    Why does this issue matter for urban governance and climate resilience?

    1. Urban Fire Safety: Requires stronger residential electrical audits and appliance safety standards.
    2. Climate Adaptation Challenge: Rising temperatures are increasing dependence on cooling infrastructure.
    3. Power Infrastructure Stress: Greater electricity demand during heatwaves increases risks of overload and voltage fluctuations.
    4. Public Awareness: Safety education regarding AC maintenance and heatwave preparedness remains limited.
    5. Building Regulation: Strengthens need for fire-compliant residential design and electrical inspections.

    Conclusion

    AC fire incidents illustrate how climate change is interacting with urban infrastructure vulnerabilities to create new public safety risks. Rising temperatures, prolonged cooling demand, and inadequate electrical preparedness have increased overheating hazards. Strengthening appliance maintenance, electrical safety compliance, heatwave preparedness, and resilient urban infrastructure remains necessary to reduce climate-linked fire vulnerabilities.

    India Cooling Action Plan (ICAP), 2019India Cooling Action Plan (ICAP), launched by the Ministry of Environment, Forest and Climate Change (MoEFCC), is the world’s first comprehensive national cooling strategy aimed at addressing rising cooling demand while ensuring environmental sustainability and energy efficiency.Cooling Demand Reduction: Targets a 20-25% reduction in cooling demand by 2037-38 across residential, commercial, transport, and cold-chain sectors through sustainable cooling technologies and better urban planning.
    Energy Efficiency: Encourages adoption of energy-efficient cooling appliances, including higher star-rated ACs and sustainable building designs to reduce electricity consumption.Climate Sustainability: Promotes reduction in greenhouse gas emissions and transition toward environmentally safer refrigerants with lower global warming potential.
    Thermal Comfort for All: Ensures affordable and accessible cooling, especially for vulnerable populations facing heat stress.Skilling and Innovation: Supports workforce development for cooling technicians and promotes domestic manufacturing under sustainable standards.

    Why is ICAP relevant to AC fire incidents?
    Reduced Cooling Load: Efficient cooling systems lower overheating risk during prolonged use.Energy Management: Reduced electricity demand decreases chances of voltage fluctuations and electrical overloads during heatwaves.Safer Cooling Infrastructure: Encourages improved appliance efficiency and maintenance practices.
    National Disaster Management Authority (NDMA): Heatwave Guidelines. The NDMA has issued heatwave management guidelines to reduce mortality, infrastructure stress, and public health risks arising from extreme temperatures.
    Preparedness: Encourages Heat Action Plans (HAPs) at city and district levels involving early warning systems, emergency coordination, hospital readiness, and inter-agency planning.
    Early Warning Systems: Facilitates temperature alerts through IMD forecasts to prepare citizens and institutions for extreme heat events.
    Public Awareness: Promotes behavioural adaptation through advisories on hydration, avoiding peak heat exposure, efficient appliance use, and household safety.
    Infrastructure Resilience: Encourages cooling shelters, green cover expansion, and urban heat mitigation measures.
    Vulnerable Group Protection: Prioritises elderly persons, outdoor workers, children, and economically weaker populations during heat stress.
    Why are NDMA Heatwave Guidelines relevant here?
    Heatwave-Driven AC Usage: Prolonged extreme temperatures increase AC dependence, overheating risks, and electricity demand.
    Urban Risk Management: Heat preparedness indirectly reduces appliance-related fire hazards.
  • Big Island (Hawaii)

    Why in the news?

    A magnitude 6.0 earthquake struck near Honaunau-Napoopoo on the Big Island.

    About the Big Island

    • The largest island in the Hawaiian archipelago
    • Part of Hawaii in the Pacific Ocean
    • Area: ~10,432 km²
    • Formed through volcanic activity

    Five Major Volcanoes

    • Kohala
    • Hualālai
    • Mauna Kea
    • Mauna Loa
    • Kīlauea

    Important Volcanoes

    Mauna Loa

    • One of the world’s largest volcanoes
    • Shield volcano
    • Greatest mass of any mountain on Earth

    Kīlauea

    • Among the world’s most active volcanoes
    • Frequently erupting since 1983

    Shield Volcano

    • A volcano with broad, gentle slopes formed by fluid lava flows. Examples: Mauna Loa and Kīlauea

    Mauna Kea

    • The highest point in Hawaii above sea level
    • Hosts major astronomical observatories

    Hawaiʻi Volcanoes National Park

    • UNESCO World Heritage Site
    • Protects Kīlauea and Mauna Loa volcanoes

    Why are Earthquakes Common in Hawaii?

    Due to:

    • Volcanic activity
    • Movement of tectonic plates
    • Hotspot volcanism

    Hotspot Volcanism

    • A hotspot is a place where hot magma rises from Earth’s mantle. As the Pacific Plate moves over it, volcanic islands form.

    [2024] Consider the following:
    1. Pyroclastic debris
    2. Ash and dust
    3. Nitrogen compounds
    4. Sulphur compounds
    How many of the above are products of volcanic eruptions?

    [A] Only one

    [B] Only two

    [C] Only three

    [D] All four

  • Wind plus heat: The triggers for deadly UP storm

    Why in the News?

    More than 100 deaths in Uttar Pradesh due to pre-monsoon thunderstorms have brought renewed attention to India’s growing vulnerability to compound weather events. In such events, multiple meteorological factors combine to intensify disasters. The event stood out because of its unusual intensity, wider geographic spread, and exceptionally high wind speeds. Several districts recorded winds above 100 kmph and touching 130 kmph, far exceeding normal pre-monsoon conditions.

    Why did the Uttar Pradesh thunderstorm become unusually deadly this year?

    1. Higher Fatality Burden: More than 100 deaths were reported, making it one of the deadliest thunderstorm events in recent years in northern India.
    2. Geographical Spread: The destruction was more widespread than usual, affecting multiple districts rather than isolated pockets.
    3. Extreme Wind Speeds: At least eight districts recorded wind speeds exceeding 100 kmph. Some locations witnessed gusts of nearly 130 kmph, substantially above the normal 40-60 kmph range associated with pre-monsoon storms.
    4. Infrastructure Vulnerability: Walls collapsed, electricity poles were uprooted, hoardings fell, and loose objects became projectiles, increasing casualties and injuries.
    5. Lightning Risk: Lightning strikes contributed to deaths, consistent with India’s recurring vulnerability to thunderstorm-associated lightning fatalities.

    How do pre-monsoon thunderstorms normally develop over northern India?

    1. Seasonality: Pre-monsoon thunderstorms are common during April and May, sometimes extending into July, particularly in northern India.
    2. Surface Heating: Intense land heating raises surface temperatures, creating unstable atmospheric conditions conducive to thunderstorm formation.
    3. Moisture Inflow: Moist southeasterly winds from the Bay of Bengal transport humidity inland, providing the moisture required for cloud formation.
    4. Atmospheric Instability: Warm moist air near the surface rises rapidly, generating cumulonimbus clouds associated with thunder, lightning, rainfall, hail, and gusty winds.
    5. Global Occurrence: Such storms are not unique to India and frequently occur in arid and semi-arid regions globally.

    What meteorological conditions intensified the storm beyond normal levels?

    1. Extreme Heat Conditions: Temperatures crossing 45°C across several regions increased surface heating and strengthened convective activity.
    2. Strong Southeasterly Winds: Persistent moisture transport from the Bay of Bengal extended unusually far inland, reportedly reaching even northwestern Uttar Pradesh.
    3. Western Disturbances: Rain-bearing systems originating beyond Iran introduced cool, dry air in the upper atmosphere, creating a sharp contrast with the warm, moist lower atmosphere.
    4. Thermal Contrast: Cool upper air interacting with hot lower air created severe instability, a classic condition for powerful thunderstorms.
    5. Compound Interaction: The storm emerged not from one factor but from the coincidence of multiple meteorological triggers operating simultaneously.

    Why are strong winds during thunderstorms particularly destructive in northern India?

    1. Wind Intensity: Normal thunderstorm winds range between 40-60 kmph, but speeds above 90 kmph are sufficient to uproot trees and damage structures.
    2. Urban Exposure: Billboards, electricity poles, weak infrastructure, and informal settlements increase disaster exposure.
    3. Flying Debris: Loose construction materials and roadside objects transform into dangerous projectiles during high-speed winds.
    4. Agricultural Losses: Standing crops, orchards, and rural infrastructure remain vulnerable during pre-monsoon storm episodes.
    5. High Population Density: The densely populated Gangetic plain amplifies human and economic losses from weather extreme.

    Why was forecasting unable to fully anticipate the scale of destruction?

    1. Forecast Availability: The India Meteorological Department (IMD) had already issued weather bulletins and warnings regarding thunderstorms.
    2. Underestimation of Wind Speed: Initial IMD forecasts predicted winds of up to 60 kmph, later revised to 70 kmph.
    3. Real-Time Escalation: Nowcast systems later indicated potential winds of 80-90 kmph, yet several districts experienced speeds exceeding 100 kmph.
    4. Forecasting Complexity: Thunderstorms are highly localised and dynamic phenomena, making precise prediction of intensity difficult.
    5. Evacuation Constraints: Unlike cyclones, thunderstorms lack a clear directional pathway, limiting targeted evacuation measures.

    How does this event compare with earlier extreme thunderstorm episodes?

    1. Historical Similarity: The meteorological pattern resembled 2018, when a similar thunderstorm event caused over 100 deaths in northern India.
    2. Recurring Hazard: Northern India experiences dozens of deaths annually from thunderstorms of varying intensity.
    3. Changing Risk Profile: Recent events indicate increasing concern regarding high-intensity short-duration weather extremes, potentially linked to broader climate variability.

    What governance and disaster-management lessons emerge from the Uttar Pradesh storm?

    1. Forecast Modernisation: Strengthens the need for high-resolution local forecasting systems and improved nowcasting capacity.
    2. Infrastructure Resilience: Ensures storm-resistant electricity networks, urban signage regulation, and structural safety standards.
    3. Early Warning Dissemination: Facilitates last-mile communication through SMS alerts, local administration, and community networks.
    4. Lightning Preparedness: Supports expansion of lightning detection systems and public advisories, especially in rural regions.
    5. Climate Adaptation: Reinforces the need for district-level climate-risk planning for compound extreme events.

    Conclusion

    The Uttar Pradesh thunderstorm demonstrates how heat stress, moisture transport, and upper-atmospheric disturbances can combine to produce severe local disasters. The event highlights the limits of conventional forecasting and reinforces the need for hyperlocal warning systems, resilient infrastructure, and climate-adaptive disaster planning. This has to be done to manage increasingly volatile pre-monsoon weather.

    PYQ Relevance

    [UPSC 2024] What is the phenomenon of ‘cloudbursts’? Explain

    Linkage: The PYQ tests conceptual understanding of extreme atmospheric phenomena, weather instability, and disaster geography. Both thunderstorms and cloudbursts involve intense atmospheric instability caused by heat, moisture, and upper-air interactions.

  • Indian National Centre for Ocean Information Services and ‘Kallakkadal’ Monitoring

    Why in the News

    Indian National Centre for Ocean Information Services (INCOIS) has installed a second Coastal Flood Monitoring System (CFMS) near Kollam Harbour to improve forecasting of ‘Kallakkadal’ or swell surge events along India’s southwest coast.

    What is ‘Kallakkadal’?

    • “Kallakkadal” is a Malayalam term meaning: “Sea that comes stealthily”
    • It refers to:
      • Sudden high-energy swell surges
      • Coastal flooding without local storms or rainfall

    Purpose

    • Improve accuracy of coastal flood forecasts
    • Study nearshore wave transformation
    • Build better early warning systems

    About Coastal Flood Monitoring System (CFMS)

    • A scientific monitoring system developed by Indian National Centre for Ocean Information Services for:
      • Real-time monitoring of coastal wave activity
      • Early warning for swell surges

    Components of CFMS

    • The system integrates:
      • Coastal Automatic Weather Station
      • Four high-frequency pressure sensors
    • Installed at: Shallow depths of 3 to 7 metres

    Why Kollam?

    • Kollam Harbour was selected because:
      • Kerala’s southwest coast frequently experiences swell surges
      • Fishing communities are highly vulnerable
    [2017] At one of the place in India, if you stand on the seashore and watch the sea, ‘you will find that the sea water recedes from the shore line a few kilometers and comes back to the shore, twice a day, and you can actually walk on the seafloor when the water recedes. This unique phenomenon is seen at 
    a. Bhavnagar 
    b. Bheemunipatnam 
    c. Chandipur 
    d. Nagapattinam 
  • A key ocean current is collapsing. This could be devastating for the world and India 

    Why in the News?

    Recent scientific studies have warned that the Atlantic Meridional Overturning Circulation (AMOC), a major ocean current system regulating global climate, could weaken by nearly 59% by 2100 due to rapid Greenland ice melt and global warming. Scientists fear that crossing a critical tipping point may disrupt monsoons, intensify El Niño events, trigger extreme weather, and severely affect agriculture and water security, including in India.

    What is the Atlantic Meridional Overturning Circulation (AMOC)?

    The Atlantic Meridional Overturning Circulation (AMOC) is a vast system of ocean currents that acts as a “global conveyor belt,” circulating water, heat, and nutrients throughout the Atlantic Ocean. It is a critical component of the Earth’s climate system, responsible for transporting warm water from the tropics toward the North Atlantic and returning cold water southward at deeper levels.

    1. Ocean Conveyor Belt: Facilitates circulation of warm saline surface water from tropical regions toward Greenland and returns cold dense water through deep ocean currents.
    2. Thermohaline Circulation: Operates through differences in temperature and salinity that determine ocean water density.
    3. Climate Regulation: Transfers heat from equatorial regions toward higher latitudes, moderating Europe’s climate.
    4. Rainfall Influence: Shapes global precipitation belts, including monsoon systems across Asia and Africa.
    5. Carbon Regulation: Supports oceanic carbon absorption and heat storage, reducing atmospheric warming intensity.

    Why is AMOC Weakening Rapidly?

    1. Greenland Ice Melt: Accelerated melting releases massive freshwater volumes into the North Atlantic.
    2. Salinity Reduction: Freshwater dilution reduces ocean salinity and weakens density-driven sinking of cold water.
    3. Global Warming: Rising atmospheric temperatures increase polar ice loss and ocean heat accumulation.
    4. Circulation Slowdown: Reduced sinking weakens the entire overturning circulation mechanism.
    5. Observed Decline: Scientific studies estimate AMOC has already weakened significantly over the last 50 years.

    How Does AMOC Influence Global Climate Systems?

    1. Heat Redistribution: Transfers tropical heat toward northern latitudes and stabilizes regional climates.
    2. European Climate Stability: The northward transport of warm water acts as a “radiator,” keeping Europe, particularly Western Europe, considerably warmer than other regions at similar latitudes.
    3. Monsoon Regulation: Influences tropical rainfall patterns and seasonal wind circulation.
      1. By shifting heat between hemispheres, it helps define the location of the Intertropical Convergence Zone (ITCZ), a major rain belt. A weaker AMOC can disrupt this, leading to weakened monsoon systems and altered rainfall in Africa, Asia, and South America.
    4. Storm Dynamics: By transporting heat, the AMOC influences the intensity and path of storms and cyclones. It specifically contributes to the formation of the North Atlantic Oscillation (NAO). Changes in its strength can alter the frequency and track of storms across the North Atlantic
    5. Marine Ecosystems: The overturning circulation, which involves deep-sea sinking in the North Atlantic, helps circulate nutrients and oxygen throughout the ocean’s layers, supporting marine biodiversity.

    Why is the Collapse of AMOC Considered a Climate Tipping Point?

    The collapse of the Atlantic Meridional Overturning Circulation (AMOC) is considered a critical climate tipping point because it represents a “point of no return” where melting Arctic ice causes irreversible shutdown of vital ocean currents, triggering catastrophic, self-sustaining changes to global weather, sea levels, and ecosystems.

    1. Irreversibility Risk: Crossing a threshold may push the system into long-term collapse difficult to reverse.
    2. Abrupt Climate Shift: Climate systems may experience sudden disruptions rather than gradual warming patterns.
    3. Non-Linear Impact: Small increases in warming may trigger disproportionately large climatic consequences.
    4. Feedback Mechanisms: Ice melt and circulation slowdown reinforce each other, accelerating instability.
    5. Planetary Consequences: Impacts may extend simultaneously across rainfall, temperature, sea level, and ecosystems.

    How Could AMOC Collapse Affect India?

    1. The “Southern Pull” on Rain: As the Northern Hemisphere cools due to lack of heat transport, the Inter-Tropical Convergence Zone (ITCZ), the belt where monsoon rains form, shifts south. This moves the core rain clouds away from the Indian landmass, leading to the projected 10% to 30% drop in rainfall.
    2. Monsoon Instability: Beyond just “less rain,” the monsoon would become erratic
    3. Agricultural Stress: Irregular rainfall threatens crop productivity and food security.
    4. Extreme Weather: Intensifies droughts, floods, heatwaves, and erratic rainfall events.
    5. Water Insecurity: Alters river recharge patterns and groundwater availability.
    6. Livelihood Vulnerability: Threatens rural populations dependent on agriculture and climate-sensitive occupations.
    7. Disaster Frequency: Increases compound climate events such as simultaneous drought-flood cycles.

    What is the Connection Between AMOC and El Niño?

    The connection between the Atlantic Meridional Overturning Circulation (AMOC) and El Niño is a critical climate interlinkage where a disruption in one ocean basin triggers “chaos” in another.

    1. Climate Interlinkage: AMOC slowdown affects Pacific Ocean circulation patterns.
    2. Global Heat Imbalance: AMOC acts as a “conveyor belt” moving heat north. Its slowdown traps excess heat in the Southern Hemisphere while cooling the North Pacific. This disturbs the delicate temperature gradients that normally regulate El Niño-Southern Oscillation (ENSO) cycles.
      1. El Niño Intensification: Weak AMOC conditions may strengthen El Niño frequency and severity.
    3. Monsoon Suppression: Strong El Niño events historically weaken Indian monsoon rainfall.
    4. Global Weather Extremes: Intensifies droughts, storms, floods, and agricultural disruptions globally.
    5. Atmospheric Feedbacks: Alters temperature gradients and global wind circulation systems.

    What Could be the Global Consequences of AMOC Collapse?

    1. European Cooling: Northern Europe may experience severe winters despite global warming.
    2. Sea-Level Rise: Eastern coast of North America could face accelerated sea-level rise.
    3. Food System Stress: Agricultural productivity may decline due to rainfall instability.
    4. Climate Migration: Large populations may face displacement due to water and livelihood crises.
    5. Economic Disruption: Insurance losses, infrastructure damage, and supply chain instability may increase.
    6. Biodiversity Loss: Marine ecosystems dependent on nutrient circulation may weaken.

    What Measures are Necessary to Prevent or Mitigate the Crisis?

    1. Emission Reduction: Accelerates decarbonisation to limit global warming below critical thresholds.
    2. Climate Adaptation: Strengthens resilient agriculture, irrigation systems, and disaster preparedness.
    3. Polar Protection: Enhances international cooperation on Arctic and Greenland ice conservation.
    4. Scientific Monitoring: Expands ocean observation systems and climate modelling.
    5. Renewable Transition: Reduces dependence on fossil fuels and stabilizes long-term climate systems.
    6. Global Cooperation: Strengthens implementation of the Paris Agreement and climate finance commitments.

    Conclusion

    The weakening of AMOC highlights the growing fragility of Earth’s interconnected climate systems under anthropogenic warming. The issue extends beyond oceanography into food security, economic stability, disaster governance, and geopolitical security. For India, the risks are particularly significant because of the economy’s dependence on monsoon-driven agriculture and climate-sensitive livelihoods. Preventing irreversible tipping points requires rapid emission reduction, climate-resilient development, strengthened scientific monitoring, and coordinated global climate action.

    PYQ Relevance

    [UPSC 2015] Explain the factors responsible for the origin of ocean currents. How do they influence regional climates, fishing and navigation?

    Linkage: This AMOC issue directly relates to the role of ocean currents in regulating global climate, monsoon systems, salinity, and heat transfer. The article expands the conventional oceanography topic into contemporary climate-change dimensions such as tipping points, Greenland ice melt, El Niño linkage, and monsoon instability affecting India.

  • AMOC Collapse and Its Impact on India 

    Why in the News

    Scientists have warned that the Atlantic Meridional Overturning Circulation (AMOC), a major Atlantic Ocean current system, could weaken drastically by 2100 due to climate change, potentially affecting global climate and the Indian monsoon.

    What is AMOC (Atlantic Meridional Overturning Circulation)?

    • A large system of ocean currents in the Atlantic Ocean often described as a global ocean conveyor belt

    How AMOC Works

    • Warm, salty surface water flows northward from the tropics
    • Near the Arctic, water cools and becomes denser
    • Dense water sinks deep into the ocean
    • Cold deep water then flows southward

    Importance of AMOC

    • Maintains relatively mild climate in Europe
    • Influences:
      • Rainfall patterns
      • Monsoons
      • Global temperature distribution
      • Marine ecosystems

    Connection with El Niño

    • El Niño
      • Periodic warming of Pacific Ocean waters
      • Influences global weather patterns
    • A weaker AMOC may: Make El Niño events more extreme and unpredictable
    [2020] With reference to Ocean Mean Temperature (OMT), which of the following statements is/are correct? 
    1.OMT is measured up to a depth of 26ºC isotherm which is 129 meters in the south-western Indian Ocean during January-March. 
    2.OMT collected during January-March can be used in assessing whether the amount of rainfall in monsoon will be less or more than a certain long-term mean. 
    Select the correct answer using the code given below: 
    a) 1 only b) 2 only c) Both 1 and 2 d) Neither 1 nor 2
  • Mayon Volcano 

    Why in the News

    The Mayon Volcano recently erupted, leading to the evacuation of thousands of people in affected areas of the Philippines.

    About Mayon Volcano

    • Type: Active stratovolcano (composite volcano)
    • Location: Albay province, Luzon Island
    • Height: 2,462 metres
    • Known as: “World’s most perfect volcanic cone” due to its symmetry

    Geographical Setting

    • Part of the Pacific Ring of Fire
    • Located near the Philippine Trench
    • Formed at a convergent plate boundary
      • Philippine Sea Plate subducting beneath the Philippine Mobile Belt

    What is a Stratovolcano

    • Tall, steep cone shaped volcano
    • Built from alternating layers of:
      • Lava
      • Pyroclastic material
    • Found mainly in subduction zones
    • Magma type:
      • Andesite and dacite (viscous lava)
    • Leads to explosive eruptions
    [2024] Consider the following: 
    1. Pyroclastic debris 
    2. Ash and dust 
    3. Nitrogen compounds 
    4. Sulphur compounds 
    How many of the above are products of volcanic eruptions? 
    [A] Only one [B] Only two [C] Only three [D] All four
  • Andaman Sea  

    Why in the News?

    • A boat carrying Rohingya refugees capsized in the Andaman Sea, highlighting its strategic and humanitarian importance.

    About the Andaman Sea

    What it is

    • A marginal sea of the northeastern Indian Ocean
    • Acts as a maritime link between:
      • South Asia
      • Southeast Asia

    Location

    • Lies between:
      • 4°N to 20°N latitude
      • 92°E to 100°E longitude

    Connected Water Bodies

    • West: Bay of Bengal
    • East: South China Sea (via Strait of Malacca)

    Boundaries

    • North: Irrawaddy delta (Myanmar)
    • East: Myanmar, Thailand, Malaysia
    • South: Indonesia (Sumatra)
    • West: Andaman & Nicobar Islands (India)

    Origin of Name

    • Derived from “Handuman” (Malay form of Hanuman)
    • Linked to ancient maritime trade and cultural exchanges
    [2020] Consider the following pairs: River – Flows into 
    1. Mekong — Andaman Sea 
    2. Thames — Irish Sea 
    3. Volga — Caspian Sea 
    4. Zambezi — Indian Ocean 
    Which of the pairs given above is/are correctly matched? 
    a) 1 and 2 only b) 3 only c) 3 and 4 only d) 1, 2 and 4 only
  • IMD Forecasts Below Normal Monsoon Due to El Niño  

    Why in the News?

    The India Meteorological Department (IMD) has forecast below normal monsoon rainfall for 2026, mainly due to the developing El Niño conditions.

    Key Highlights

    • Expected rainfall: 92% of Long Period Average (LPA)
    • Classification: Below Normal Monsoon
    • Error margin: ±5%
    • Monsoon period: June to September
    • India receives over 70% of annual rainfall during this period

    What is Long Period Average (LPA)

    • LPA: Average rainfall during monsoon season
    • Current LPA period: 1971 to 2020
    • LPA rainfall: 87 cm

    Monsoon Classification by IMD

    • Above normal: >104% of LPA
    • Normal: 96% to 104%
    • Below normal: 90% to 96%
    • Deficient: <90%

    2026 Forecast: 92% → Below Normal

    [2011] La Niña is suspected to have caused recent floods in Australia. How is La Niña different from El Niño? 
    1 La Niña is characterized by unusually cold ocean temperature in the equatorial Indian Ocean whereas El Niño is characterized by unusually warm ocean temperature in the equatorial Pacific Ocean. 
    2 El Niño has an adverse effect on the southwest monsoon of India, but La Niña has no effect on monsoon climate. 
    Which of the statements given above is/are correct? 
    (a) 1 only (b) 2 only (c) Both 1 and 2 (d) Neither 1 nor 2

  • [1st April 2026] The Hindu Oped: Counting people is not counting disaster risk

    PYQ Relevance[UPSC 2019] Vulnerability is an essential element for defining disaster impacts and its threat to people. How and in what ways can vulnerability to disasters be characterized? Discuss different types of vulnerability with reference to disasters.Linkage: The PYQ tests core concepts of vulnerability, exposure, and disaster risk assessment, which form the foundation of GS-3 Disaster Management. The article directly critiques flawed vulnerability measurement (income-based proxy), reinforcing the need for multidimensional vulnerability assessment as demanded in the PYQ.

    Mentor’s Comment

    There is a critical flaw in India’s disaster financing architecture, the shift from risk-based assessment to population-based allocation. The issue is in the news due to concerns over the 16th Finance Commission’s disaster risk funding formula, which paradoxically allocates higher funds to States with larger populations rather than those with greater disaster exposure. This marks a sharp departure from earlier approaches and undermines decades of progress in disaster preparedness. The scale of the problem is significant, States like Odisha, with the highest hazard score (12), receive less effective consideration than States like Bihar (224.2) and Uttar Pradesh (413.2) due to population weighting.

    What structural flaw exists in the disaster funding formula?

    1. Multiplicative Risk Formula: Uses Disaster Risk Index (DRI = Hazard × Exposure × Vulnerability), but distorts outcomes due to flawed exposure metrics.
    2. Population-Based Exposure: Defines exposure as total population (scaled 1-25), ignoring actual hazard-prone zones.
    3. Bias Toward Larger States: Ensures States like Uttar Pradesh receive higher weight despite lower hazard intensity.
    4. Departure from Previous Approach: Replaces additive model of 15th Finance Commission, which treated hazard and vulnerability separately.
    5. Outcome Distortion: Rewards demographic size rather than disaster risk, contradicting risk-based allocation principles.

    Why is ‘exposure’ measurement scientifically flawed?

    1. Incorrect Definition: Uses total population instead of hazard-zone population.
    2. IPCC Standard Ignored: Defines exposure as people in hazard-prone areas, not administrative boundaries.
    3. Misleading Comparisons: Inland plateau populations treated equal to cyclone-prone coastal populations.
    4. Example: Odisha’s high-risk coastline equated with safer inland regions in other States.
    5. Result: Artificial inflation of exposure scores for populous but less vulnerable States.

    How does vulnerability measurement misrepresent actual risk?

    1. Income-Based Proxy: Uses per capita NSDP, which measures fiscal capacity, not vulnerability.
    2. Multidimensional Nature Ignored: Overlooks housing quality, health infrastructure, and early warning access.
    3. Kerala Case Study: Despite ₹31,000 crore flood damages (2018), receives low vulnerability score (1.073).
    4. Hidden Inequality: Average income masks intra-state disparities and disaster susceptibility.
    5. Outcome: Underestimates real vulnerability in disaster-prone but relatively richer States.

    Why does the formula penalize disaster-prone States?

    1. Population Bias: Prioritizes demographic size over risk intensity.
    2. Funding Paradox: Odisha (highest hazard score) loses out due to lower population score.
    3. Disproportionate Allocation: Bihar (224.2) and UP (413.2) overshadow Odisha despite lower hazard exposure.
    4. Kerala’s Loss: Loses 0.78 percentage points despite high vulnerability ranking.
    5. Systemic Inequity: Smaller, disaster-prone States receive inadequate fiscal support.

    What are the implications for disaster governance in India?

    1. Misallocation of Resources: Funds diverted away from high-risk zones.
    2. Reduced Preparedness: States with higher hazard exposure face fiscal constraints.
    3. Climate Risk Escalation: Cyclones, floods, and droughts increasing in intensity and frequency.
    4. Regional Inequality: Coastal and northeastern States disproportionately affected.
    5. Policy Credibility Issue: Undermines objective of risk-based disaster financing.

    What reforms are required in disaster risk assessment?

    1. Hazard-Zone Mapping: Measures exposure based on population in disaster-prone areas.
    2. Composite Vulnerability Index: Includes housing, health, agriculture, and infrastructure indicators.
    3. Use of Data Systems: Integrates Building Materials and Technology Promotion Council (BMTPC) Vulnerability Atlas, National Family Health Survey-5 (NFHS-5), Pradhan Mantri Fasal Bima Yojana (PMFBY) database, National Health Mission (NHM) facility surveys, and India Meteorological Department (IMD) monitoring records. 
    4. Institutional Mechanism: Mandates NDMA to publish annual State Disaster Vulnerability Index.
    5. Policy Continuity: Institutionalizes methodology across Finance Commissions. 

    Conclusion

    A population-based approach to disaster funding undermines the principle of risk-sensitive governance. A shift toward hazard-specific exposure mapping and multidimensional vulnerability assessment is essential to ensure equitable and effective disaster resilience in India.