UPSC CSE 2026 Essay Paper Discussion
GS Paper 1 10 marks · 150w 9 min Easy

How are climate change and the sea level rise affecting the very existence of many island nations? Discuss with examples.

Subtopic: Geography · climate change and sea-level rise

Model answer outline

How to structure your answer

Introduction (accelerating sea-level rise) → Submergence and freshwater loss on low atolls → Livelihood collapse: reefs, fisheries, tourism → Cyclones, forced migration and sovereignty questions → Global responses: AOSIS, Loss and Damage Fund, ITLOS → Conclusion (climate justice test)
Full model answer

Detailed model answer

209 words · target 150 words · 9 min

Introduction

Global mean sea level is rising at roughly 4.5 mm a year and accelerating (satellite record; IPCC AR6). For low-lying island nations this converts climate change from a development challenge into an existential threat.

How their very existence is threatened

  • Physical submergence: over 80% of the Maldives lies below one metre; Tuvalu's highest point is under five metres; some Kiribati islets have already disappeared.
  • Freshwater loss: saltwater intrusion contaminates the thin groundwater lenses of atolls (Marshall Islands, Maldives), making islands uninhabitable before they submerge.
  • Livelihood collapse: ocean warming and acidification bleach coral reefs, undermining the fisheries and tourism on which these economies rest.
  • Intensified hazards: stronger cyclones and storm surges — Cyclone Winston (Fiji, 2016) caused losses approaching a third of GDP.
  • Sovereignty at stake: shrinking coastlines threaten maritime baselines, EEZ claims and even statehood, while land loss forces migration — Kiribati bought land in Fiji (2014), and the Tuvalu–Australia Falepili Union treaty (2023) created a climate-mobility pathway.
  • Cultural erasure: relocations such as that of the Carteret Islanders (Papua New Guinea) sever communities from ancestral land.

Conclusion

Through AOSIS advocacy, the Loss and Damage Fund operationalised at COP28 and the ITLOS advisory opinion (2024) on states' climate obligations, island nations are converting vulnerability into legal and diplomatic leverage. Their survival is the sternest test of global climate justice.

Key points

What an examiner expects to see

  • Sea-level rise of about 4.5 mm a year, and accelerating, threatens outright submergence of atoll nations lying one to five metres above the sea.
  • Saltwater intrusion destroys thin freshwater lenses, rendering islands uninhabitable well before physical submergence.
  • Coral bleaching and ocean acidification undermine fisheries and tourism — the economic base of most island states.
  • Intensified cyclones and storm surges inflict repeated GDP-scale losses on small economies.
  • Sovereignty dimension: shrinking baselines imperil EEZs and statehood, and climate-driven migration has already begun.
  • Island states are converting vulnerability into leverage — AOSIS, the Loss and Damage Fund, and the 2024 ITLOS advisory opinion.
Examples to use

Concrete cases, schemes and judgments

  • Tuvalu–Australia Falepili Union treaty (2023) creating a climate-mobility pathway
  • Kiribati's purchase of land in Fiji (2014) as insurance
  • Cyclone Winston, Fiji (2016) — losses approaching a third of GDP
  • Maldives — over 80% of land below one metre elevation
  • Carteret Islanders (Papua New Guinea) — among the first climate relocations
Keywords / terms

Terminology to weave into the answer

sea-level riseatoll freshwater lensclimate migrationAOSISLoss and Damage Fundclimate justice

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