From Baselines To High Seas: The International Legal Regime Of The Oceans

Introduction

Over two-thirds of the Earth's surface is made up of oceans, which are essential for international trade, biodiversity, climate regulation, and food security. These enormous oceans were mostly uncontrolled for centuries, subject solely to maritime nations' power conflicts and customs. A structured legal order over the oceans became necessary as a result of the expansion of global trade, improvements in navigation technology, and easier access to offshore resources. In response, public international law progressively developed a legal framework that strikes a balance between national interests and international collaboration. As a result, there is a complicated but sensible system of marine laws that govern resource exploitation, maritime navigation, territorial claims, and environmental obligations. These rules, codified mainly in the United Nations Convention on the Law of the Sea (UNCLOS), form the backbone of global maritime governance today.

Evolution of Sea Laws

The seas have always been viewed as either sovereignly claimed or open to all. In his ground breaking work Mare Liberum (1609), Dutch jurist Hugo Grotius argued in favour of the freedom of the sea’s theory, which holds that no country has the right to claim sovereignty over ocean territory. His thesis facilitated international trade and benefited new maritime powers.

On the contrary, the English scholar John Selden claimed that seas might be legally acquired in his 1635 work Mare Clausum. Debates persisted into the 20th century, despite Grotius' theory gradually gaining broader support, especially as global trade increased. Calls for codification grew as a result of the legal ambiguity, particularly in light of offshore commercial activity and technology advancements.

UNCLOS And Maritime Zones

The turning point came with the adoption of the United Nations Convention on the Law of the Sea (UNCLOS) in 1982. Often referred to as the “Constitution of the Oceans,” UNCLOS establishes a comprehensive legal regime governing maritime zones, navigation, and marine resources.

UNCLOS defines five main maritime zones:

• Territorial Sea: Extends up to 12 nautical miles from the baseline. The coastal state enjoys full sovereignty, subject to the right of innocent passage by foreign vessels.

• Contiguous Zone: Spans 24 nautical miles from the baseline. Here, the coastal state can enforce laws related to customs, immigration, and public health.

• Exclusive Economic Zone (EEZ): Stretches up to 200 nautical miles, giving the coastal state exclusive rights over natural resources, both living and non-living. Navigation and overflight rights of other states remain unaffected.

• Continental Shelf: Refers to the seabed and subsoil extending to the outer edge of the continental margin or 200 nautical miles. Coastal states have sovereign rights to exploit natural resources.

• High Seas: Beyond national jurisdiction, high seas are open to all states. Activities such as navigation, fishing, and research are governed by general international principles.

Institutions And Dispute Resolution

UNCLOS also provides institutional mechanisms to resolve maritime disputes and regulate international cooperation. The International Tribunal for the Law of the Sea (ITLOS), headquartered in Hamburg, adjudicates legal disputes arising from interpretation of UNCLOS.

Additionally, the International Seabed Authority (ISA) oversees mineral resource activities in deep-sea areas beyond national jurisdictions. The Commission on the Limits of the Continental Shelf (CLCS) helps coastal states delineate outer continental shelf boundaries using geological and scientific evidence.

Contemporary Relevance And Challenges

In recent years, legal issues concerning the seas have become more complex due to rising geopolitical tensions, environmental degradation, and climate change. Disputes over overlapping claims in areas like the South China Sea have tested the effectiveness of UNCLOS. Despite a 2016 arbitral ruling against China’s expansive maritime claims, compliance remains limited.

Rising sea levels may also cause marine baselines to change, altering the extent of EEZs and territorial waters. Low-lying island nations are directly impacted by this, as many may no longer have access to maritime resources and sovereign space. The international community is becoming more committed to controlling environmental impacts on marine biodiversity, as seen by initiatives like the 2023 High Seas Treaty under the Biodiversity Beyond National Jurisdiction (BBNJ) project. These changes reflect a growing comprehension of marine governance based on the fundamental tenets of UNCLOS.

Conclusion

A key framework for preserving harmony, collaboration, and fair access in maritime areas is provided by sea laws under public international law. The development of maritime law, from the early philosophical discussions of Grotius and Selden to the thorough codification in UNCLOS, shows the increasing complexity of interests associated to the ocean. These laws offer a crucial balance between state sovereignty and the global commons in the face of geopolitical conflicts, environmental problems, and technological breakthroughs that are changing the oceans.

In addition to defining maritime zones, the legal framework established by UNCLOS also strengthens obligations for environmental preservation, dispute settlement, and marine resource management.  The flexibility and implementation of these regulations are increasingly more important in light of emerging issues like deep sea mining, rising sea levels, and threats to biodiversity.  Legal definitions alone are not enough to maintain the integrity of the oceans.  It demands international agreement, collaboration in science, and a dedication to shared stewardship.  In accordance with the spirit of international law, the seas will continue to benefit humanity as a whole if institutional processes are strengthened, compliance is encouraged, and fair principles are upheld.

References:

1. United Nations Convention on the Law of the Sea, Dec. 10, 1982, 1833 U.N.T.S. 397.

2. United Nations Convention on the Law of the Sea, Dec. 10, 1982, 1833 U.N.T.S. 397, arts. 2–3, 17.

3. United Nations Convention on the Law of the Sea, Dec. 10, 1982, 1833 U.N.T.S. 397, art. 33.

4. United Nations Convention on the Law of the Sea, Dec. 10, 1982, 1833 U.N.T.S. 397, arts. 56–58.

5. United Nations Convention on the Law of the Sea, Dec. 10, 1982, 1833 U.N.T.S. 397, art. 76.

6. United Nations Convention on the Law of the Sea, Dec. 10, 1982, 1833 U.N.T.S. 397, arts. 87–89.

7. Statute of the International Tribunal for the Law of the Sea, Dec. 10, 1982, 1833 U.N.T.S. 561.

8. The South China Sea Arbitration (Phil. V. China), PCA Case No. 2013–19, Award (Perm. Ct. Arb. July 12, 2016).

This article is authored by Hima N, who was among the Top 40 performers in the Civil Procedural Law Quiz Competition organized by Lets Learn Law. The views and opinions expressed in this piece are solely those of the author.