Sea Level Rise: UN Report Highlights Coastal Vulnerability

UPSC Mapping

Exam	Topic
Prelims	Environment and Ecology
Mains	GS Paper 3 (Environment)

Quick Facts

Record Rise (2024)	5.9 mm
Projected Increase	0.5 m by 2100
Vulnerable Population	~770 million globally

Article

What is Sea Level Rise?

Sea Level Rise refers to the long-term increase in the average height of the world’s oceans. This phenomenon primarily results from the thermal expansion of seawater as it warms. Additionally, the accelerated melting of land-based ice sheets and glaciers contributes significantly to this global trend. The combined effect permanently alters coastal topographies and threatens human settlements.

The recent United Nations report emphasizes that this trend is accelerating at an alarming rate. It threatens approximately 770 million people, or one in every ten individuals globally. These populations reside in low-lying coastal areas and face existential risks. The crisis disproportionately impacts Indigenous communities and Small Island Developing States (SIDS).

Why is Sea Level Rise in News?

The United Nations recently presented a critical report on this issue. The document titled ‘Challenges related to sea-level rise and ways and approaches to address it’ was unveiled during the 55th Pacific Islands Forum Leaders Meeting in Palau. This forum highlights the acute vulnerability of island nations to climate change. You can verify these global environmental updates through the official PIB release on climate action.

India-specific findings in the report reveal severe regional vulnerabilities. Major South Asian cities like Mumbai, Kolkata, and Dhaka are particularly at risk. More than 14 million people in these specific urban areas face immediate threats of permanent inundation. Furthermore, land subsidence in cities like Mumbai compounds the effects of Sea Level Rise. This combination intensifies coastal flooding and infrastructure damage.

Key Features of the UN Report

• Mass Displacement: The report warns of large-scale climate migration as coastal habitats become permanently uninhabitable.
• Infrastructure Loss: Rising waters threaten critical coastal infrastructure, including ports, roads, and residential buildings.
• Saltwater Intrusion: Encroaching seawater contaminates freshwater aquifers, severely impacting drinking water and agricultural viability.
• Maritime Disputes: Shifting coastlines could potentially alter baselines, triggering complex international maritime boundary disputes.
• Disproportionate Impact: The findings explicitly highlight the extreme vulnerability of Small Island Developing States and Indigenous populations.

Challenges in Addressing Sea Level Rise

Despite clear scientific warnings, mitigating the impacts of Sea Level Rise faces several structural and geopolitical hurdles.

• Adaptation Finance Gaps: Developing nations lack the massive financial resources required to build resilient coastal defenses and relocate communities.
• Compounding Factors: Localized issues like land subsidence and groundwater extraction worsen the relative rate of sea level rise in urban centers.
• Data Deficits: Many vulnerable regions lack high-resolution scientific data needed for precise vulnerability mapping and early-warning systems.
• Emission Inertia: Global greenhouse gas emissions remain high, ensuring that thermal expansion and ice melt will continue for centuries.
• Legal Ambiguities: International law currently lacks clear frameworks for protecting the maritime rights of nations that lose territory to the ocean.

Way Forward

To mitigate the catastrophic impacts of Sea Level Rise, the global community must prioritize faster and deeper emission cuts. This remains the only permanent solution to halt the long-term drivers of ocean warming and ice melt. Simultaneously, nations must invest heavily in stronger early-warning systems and nature-based coastal defenses like mangrove restoration.

Moreover, international frameworks must guarantee greater adaptation finance for the most vulnerable nations. The NITI Aayog has consistently emphasized the need for localized, data-driven climate resilience strategies in India. This comprehensive approach will ultimately protect millions of lives and secure coastal economies against future climate shocks.

Prelims Package

Q1. Consider the following statements regarding the recent UN report on Sea Level Rise:

1. Global sea level rose by a record 5.9 mm in 2024.
2. The report was presented during the 55th Pacific Islands Forum Leaders Meeting.
Which of the statements given above is/are correct?

• (a) 1 only
• (b) 2 only
• (c) Both 1 and 2
• (d) Neither 1 nor 2

Answer: (c) Both statements are correct as per the recent United Nations report findings.

Q2. Approximately how many people globally are threatened by sea level rise in low-lying coastal areas?

• (a) 100 million
• (b) 350 million
• (c) 770 million
• (d) 1.2 billion

Answer: (c) The UN report states that approximately 770 million people, or 1 in 10 globally, are threatened.

Q3. Which Indian cities are specifically highlighted as particularly vulnerable in the UN report?

• (a) Chennai and Kochi
• (b) Mumbai, Kolkata, and Dhaka
• (c) Delhi and Pune
• (d) Visakhapatnam and Bhubaneswar

Answer: (b) The report specifically highlights Mumbai, Kolkata, and Dhaka as highly vulnerable South Asian cities.

Q4. What local factor compounds the effects of sea level rise in cities like Mumbai?

• (a) Deforestation
• (b) Land subsidence
• (c) Urban heat island effect
• (d) Soil erosion

Answer: (b) Land subsidence combined with sea level rise can intensify coastal flooding in these urban areas.

Q5. Which of the following is NOT a recommendation by the UN to address sea level rise?

• (a) Faster emission cuts
• (b) Stronger early-warning systems
• (c) Increased fossil fuel subsidies
• (d) Greater adaptation finance

Answer: (c) The UN recommends emission cuts, early-warning systems, adaptation finance, and improved scientific data.

Mains Package

Q1. Discuss the implications of the UN report on Sea Level Rise for coastal communities in India. (150 words, 10 marks)

Answer Structure:

• Intro: Briefly introduce the UN report findings and the specific vulnerability of Indian coastal cities.
• Body: Implications (threat to 14 million people in Mumbai/Kolkata/Dhaka, land subsidence compounding risks, saltwater intrusion, infrastructure damage); Challenges (adaptation finance, data deficits).
• Conclusion: Emphasize the need for integrated coastal zone management and nature-based solutions.

Q2. ‘Climate change adaptation requires a multi-pronged approach combining mitigation, finance, and technology.’ Critically examine in the context of rising sea levels. (250 words, 15 marks)

Answer Structure:

• Intro: Contextualize the accelerating rate of sea level rise and its existential threat to SIDS and low-lying coastal areas.
• Body: Mitigation (deep emission cuts to address root causes); Finance (fulfilling climate finance pledges for adaptation in developing nations); Technology (early-warning systems, high-resolution mapping, resilient infrastructure); Challenges (implementation gaps, geopolitical friction).
• Conclusion: Summarize that only a holistic, globally coordinated strategy can safeguard vulnerable populations from irreversible coastal inundation.

FAQs

What is the projected sea level rise by 2100 according to the UN report?

The UN report projects that global sea levels could increase by at least 0.5 meters by the year 2100 if current trends continue.

Why are cities like Mumbai particularly vulnerable to sea level rise?

Cities like Mumbai face a dual threat: rising global sea levels combined with localized land subsidence, which significantly intensifies the risk of permanent coastal inundation.

What are the primary recommendations of the UN to address this crisis?

The UN recommends faster greenhouse gas emission cuts, stronger early-warning systems, greater adaptation finance, improved scientific data, and targeted support for vulnerable communities.