Climate Change and the Future of Maritime Boundaries Rethinking Baselines, Islands and Maritime Entitlements in the Indian Ocean
DOI:
https://doi.org/10.70670/sra.v4i1.2597Keywords:
Climate Change, Sea Level Rise, Maritime Boundaries, Baselines, Islands, Indian Ocean, UNCLOS, International Court of JusticeAbstract
Climate change is altering the physical geography on which the international law of the sea was designed. Rising seas, coastal erosion, reef degradation and recurrent inundation can move low water lines, submerge low tide elevations and impair the habitability of small islands. These processes are especially consequential in the Indian Ocean, where continental coasts, archipelagic States and low lying island States depend upon maritime zones for fisheries, security, transport and public revenue. This article examines whether maritime baselines, island status and maritime entitlements should continue to follow an ambulatory model or should acquire legal stability once lawfully established and publicized. It uses doctrinal and comparative legal analysis, supported by a limited descriptive examination of climate data and Indian Ocean dispute practice. The analysis finds that the text of the United Nations Convention on the Law of the Sea does not expressly resolve climate driven coastline change, but recent State practice, the work of the International Law Commission and the 2025 Advisory Opinion of the International Court of Justice substantially strengthen the case for maintaining duly established maritime zones. The article argues for a model of functional permanence. Under this model, deposited baselines and outer limits remain effective despite climate related physical change, established maritime boundaries remain stable, and the legal status of an island is assessed with caution rather than repeatedly recalculated after each environmental shock. Transparency, accurate hydrographic information, negotiated boundary settlement and judicial clarification remain essential. This approach best reconciles textual fidelity, equity, climate justice and regional stability in the Indian Ocean.
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