Model Answer
0 min readIntroduction
Sea-surface temperature (SST) refers to the temperature of the water at the ocean’s surface. It’s a crucial parameter in the climate system, significantly influenced by solar radiation, atmospheric conditions, and ocean currents. Recent decades have witnessed a consistent rise in SST, largely attributed to anthropogenic climate change, with 2023 being recorded as the warmest year on record for ocean temperatures. This warming trend isn’t uniform, leading to localized hotspots and triggering a cascade of hazards impacting both natural ecosystems and human societies. Understanding these hazards is critical for effective mitigation and adaptation strategies.
Ecological Hazards
Rising SSTs profoundly impact marine ecosystems:
- Coral Bleaching: Increased temperatures cause corals to expel symbiotic algae, leading to bleaching and potential coral reef death. The Great Barrier Reef has experienced multiple mass bleaching events (e.g., 2016, 2017, 2020, 2022) due to elevated SSTs.
- Harmful Algal Blooms (HABs): Warmer waters promote the growth of toxic algae, leading to HABs. These blooms can contaminate seafood, harm marine life, and impact human health.
- Shifts in Species Distribution: Marine species are migrating towards cooler waters, disrupting food webs and impacting fisheries. For example, commercially important fish species are moving poleward.
- Ocean Acidification: While not directly caused by temperature, warmer water absorbs less CO2, exacerbating ocean acidification, further stressing marine ecosystems.
Meteorological Hazards
SSTs are a key driver of weather patterns, and their increase intensifies several meteorological hazards:
- Increased Frequency and Intensity of Tropical Cyclones: Warmer SSTs provide more energy for cyclone formation and intensification. The North Atlantic has seen an increase in rapid intensification events in recent years.
- Marine Heatwaves (MHWs): Prolonged periods of unusually warm SSTs, MHWs can devastate marine ecosystems and contribute to extreme weather events. The 2022-23 MHW in the Mediterranean Sea was particularly severe.
- Altered Monsoon Patterns: SST anomalies in the Indian and Pacific Oceans influence the Indian monsoon, leading to unpredictable rainfall patterns and increased risk of droughts or floods. The El Niño-Southern Oscillation (ENSO) is a prime example.
- Increased Atmospheric Moisture: Warmer water evaporates more readily, increasing atmospheric moisture content and contributing to heavier rainfall events and flooding.
Socio-Economic Hazards
The ecological and meteorological hazards translate into significant socio-economic consequences:
- Fisheries Decline: Shifts in species distribution and coral reef degradation impact fisheries, threatening food security and livelihoods.
- Coastal Erosion and Flooding: Rising sea levels, exacerbated by thermal expansion of water, increase coastal erosion and flooding, displacing communities and damaging infrastructure.
- Impact on Tourism: Degradation of coral reefs and beaches negatively impacts tourism revenue.
- Threat to Maritime Transport: Extreme weather events disrupt maritime transport and trade routes.
| Hazard | Impact | Example |
|---|---|---|
| Coral Bleaching | Loss of biodiversity, reduced tourism | Great Barrier Reef (Australia) |
| Tropical Cyclones | Infrastructure damage, loss of life | Cyclone Amphan (India, 2020) |
| Sea Level Rise | Coastal inundation, displacement | Maldives |
Conclusion
The rise in sea-surface temperature presents a complex web of interconnected hazards, impacting ecological balance, weather patterns, and human well-being. Addressing this challenge requires a multi-faceted approach encompassing aggressive mitigation of greenhouse gas emissions, investment in climate adaptation strategies (e.g., coastal protection, resilient infrastructure), and enhanced monitoring and prediction capabilities. International cooperation and sustainable ocean management are crucial to minimize the devastating consequences of warming oceans and ensure a sustainable future.
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.