Daily Hot Topic
Kolkata Heatwave: Breaking Records
GS-1 Mains
- Kolkata experienced a record-breaking heatwave in April 2024.
- Key points:
- Second-highest April temperature in 70 years recorded on April 25 (41.6°C).
- Joint highest April temperature in 70 years recorded on April 29 (41.7°C).
- Highest April temperature ever recorded on April 30 (43°C), just 0.3°C lower than the all-time record (1954).
- Warmest April in a decade.
- Possible Causes:
- Continuous northwesterly dry winds.
- Movement of moisture away from the Bay of Bengal.
- Global warming.
- El Nino phenomenon (disrupting weather patterns).
- Reduced number of “norwesters” (cooling thunderstorms).
- Impact:
- Increased heat stress and health risks
Kolkata Heatwave: The Future Looks Bleak (AR6 Report, UN)
Future projections (worst-case scenario):
- Highest temperature in Kolkata may reach 49.6°C by 2100 (compared to current record of 43.9°C).
- Mean temperature may rise 4.5°C by 2100 (compared to pre-industrial era).
- City may experience nearly 150 days above 35°C by 2100.
Causes:
- Global warming.
- Urban heat island effect:
- Reduced ventilation due to buildings.
- Heat generation from human activities.
- Heat absorption by concrete and building materials.
- Limited vegetation.
- Urbanization:
- Kolkata has seen the highest rise in surface air temperature (2.7°C) among major cities (1950-2018).
- Over 80% of warming linked to Kolkata itself.
- Blue-green infrastructure (water bodies, greenery) is declining.
Impacts:
- Increased extreme heat events and heatwaves.
Solutions:
- Heat action plans.
- Prioritize implementation in highly humid places like Kolkata.
- Protect water bodies.
- Increase green cover.
- Embrace renewable energy.
- Sustainable urban planning.
- Collective action to combat climate change.