UPSC Mains PYQ

🔆 UPSC MAINS ANSWER WRITING 📝 Q. What is Sea Surface Temperature (SST) rise? How does it affect the formation of tropical cyclones? (10 Marks | 150 Words) Answer 📍 Introduction ✅ Sea Surface Temperature (SST) Rise refers to the increase in the temperature of the ocean’s upper layer, primarily due to anthropogenic climate change. ✅ Oceans absorb nearly 90% of the excess heat trapped by greenhouse gases, making SST a key driver of climate change and tropical cyclone formation. 📍 Phenomenon of Sea Surface Temperature Rise ✅ Greenhouse Gas Emissions & Ocean Heat Absorption Higher greenhouse gas concentrations trap heat, causing oceans to absorb more thermal energy and increasing SST. ✅ Carbon Dioxide Absorption Oceans absorb nearly 30% of human-emitted CO₂, altering ocean chemistry and contributing to warming. ✅ Albedo Effect Melting polar ice reduces Earth’s reflectivity, allowing oceans to absorb more solar radiation, creating a positive feedback loop. ✅ Global Warming Global average temperatures have increased by nearly 1.1°C since pre-industrial times, leading to warmer ocean surfaces. ✅ Altered Ocean Currents Changes in ocean circulation such as the Atlantic Meridional Overturning Circulation (AMOC) redistribute heat unevenly, causing regional warming. ✅ Enhanced Solar Heat Retention Higher greenhouse gas concentrations increase heat retention, enabling oceans to store more thermal energy. 📍 Impact of SST Rise on Tropical Cyclone Formation ✅ Increases Cyclone Intensity Warmer oceans provide greater latent heat, strengthening tropical cyclones. Example: Cyclone Amphan (2020) rapidly intensified over the warm Bay of Bengal. ✅ More Frequent Severe Cyclones Higher SSTs increase the occurrence of very severe cyclonic storms. Example: 2020 Atlantic Hurricane Season recorded an exceptionally high number of storms. ✅ Heavier Rainfall Warmer seas increase atmospheric moisture, resulting in intense rainfall and flooding. ✅ Longer Cyclone Duration Continuous heat supply enables cyclones to retain strength for longer durations. Example: Cyclone Idai (2019) maintained high intensity over the warm Mozambique Channel. ✅ Shift in Cyclone Tracks Anomalous SSTs can alter cyclone pathways, exposing new regions to cyclone risk. Example: Hurricane Ophelia (2017) reached Ireland due to unusually warm North Atlantic waters. ✅ Higher Coastal Vulnerability Countries bordering the Indian Ocean and Pacific Ocean are increasingly exposed to stronger cyclones. 📍 Conclusion ✅ Rising Sea Surface Temperatures are increasing the frequency, intensity, rainfall, duration, and geographical spread of tropical cyclones. ✅ Strengthening climate mitigation, early warning systems, coastal resilience, and disaster preparedness is essential to reduce future cyclone-related risks. #Answer