Sea Levels Rising

Syllabus: GS3/Environment 

In News 

• Antonio Guterres highlighted the threat of sea level rise to Pacific countries like Tonga, with severe global impacts on coastal communities.

Key Highlights 

• Rate of Sea Level Rise: Global sea levels have risen over 20 cm since 1880, faster than any time in the last 3,000 years. The rate of rise has accelerated, with 2023 recording the highest sea levels.
• Unequal Rise: Sea levels are not rising equally across the globe; parts of the southwestern Pacific have seen rates nearly double the global average since 1993.
• Depending on climate action, sea levels could rise 38 cm by 2100 if global warming is limited to 1.5°C, or up to 56 cm with 2.7°C warming. Extreme cases predict up to 2 meters by 2100.

Causes of Sea Level Rise:

• Global warming caused by fossil fuel emissions.
• Thermal expansion as oceans heat up.
• Melting ice sheets and glaciers, particularly in Antarctica and Greenland.
• Groundwater pumping also contributes to rising sea levels.

Impact of Rising Seas: 

• Every 2.5 cm of sea rise can result in 2.5 meters of lost beachfront, increased storm surge, and high tides.
•  Each centimeter exposes an additional 6 million people to coastal flooding.
• Exceeding 1.5°C warming could lead to irreversible melting of the Greenland and West Antarctic ice sheets, significantly raising sea levels.

Vulnerable Regions:

•  Low-lying islands (e.g., Fiji, Maldives, Tuvalu) face existential threats. Coastal cities, river deltas, and areas in tropical Asia (Bangladesh, India, China) are also highly vulnerable.
• Global Impact: Nearly 40% of the world’s population lives near coastlines, with major cities like Cairo, Mumbai, Lagos, and London at risk of severe impacts.

Measures 

• Reducing emissions to prevent further rise.
• Adaptation strategies such as sea walls, storm surge barriers, and flood-resistant infrastructure.
• Nature-based solutions like regenerating mangroves and preventing coastal erosion.
• Relocating villages in low-lying areas or building floating cities in places like the Maldives and Tuvalu.

Source:IE