Subject: Physical Geography

The recent confirmation of the fourth global coral bleaching event in April 2024 by NOAA and ICRI highlights the devastating impact of global warming on coral ecosystems, threatening marine biodiversity and coastal communities worldwide.

Impact of Global Warming on Coral Life Systems

Direct Physical Effects

• Temperature Stress: Rising ocean temperatures cause coral bleaching by expelling symbiotic algae, leading to widespread death of coral colonies.
• Ocean Acidification: Increased CO2 absorption makes it difficult for corals to build their calcium carbonate skeletons.
• According to recent surveys, 20-25% decline in Indian coral cover over the last decade due to climate change and overfishing.

Regional Impacts

• Indian Ocean Region: Severe bleaching reported in Tanzania, Kenya, Mauritius, Seychelles, and western Indonesia due to prolonged heatwaves.
• Indian Coral Ecosystems: More than 50% of reefs in the Andaman and Nicobar Islands and Gulf of Kutch experienced bleaching due to rising sea surface temperatures.
• Lakshadweep Islands: 90% of coral species face risk from thermal stress as per NCSCM research.

Ecological Consequences

• Biodiversity Loss: Decline in reef-dependent species including fish, sponges, and giant clams.
• Ecosystem Disruption: Breakdown of coral reef food chains affecting marine life sustainability.
• Habitat Destruction: Loss of breeding grounds for numerous marine species.

Conservation Measures

• Legal Framework: Implementation of Coastal Regulation Zone (CRZ) Notification (2019) and Wildlife Protection Act (1972).
• Protected Areas: Designation of major reef areas as marine protected zones.
• National Initiatives: Central Sector Scheme under National Coastal Mission Programme focusing on restoration and monitoring.

The ongoing threat to coral ecosystems demands urgent global action through international cooperation and implementation of strict climate change mitigation measures. Examples like Australia's Great Barrier Reef Marine Park and India's coral restoration programs demonstrate the possibility of protecting these vital marine ecosystems through coordinated conservation efforts.