Climate change is going to cause a redrawing of the physical map of the planet. As has happened during countless past climatic shifts, some areas will flood and others will emerge from their shrouds of ice, turning previously frozen-over sea-lanes into watery highways.
The difference this time is that we are in an era of international law, in which political boundaries are closely and rigidly tied to physical ones. This is especially true when it comes to maritime borders that, legally, are often determined by coastlines. As climate change triggers sea-level rises and, as a result, coastline retreat — or, in extreme cases, the complete disappearance of low-lying islands — might maritime boundaries shift as well?
The United Nations Convention on the Law of the Sea (UNCLOS), which came into force in 1994, attempts to create norms for determining maritime boundaries. Unfortunately, UNCLOS doesn’t take into account the physical changes that will be caused by climate change. UNCLOS freezes coastlines and borders at a specific point in time – until they are challenged or revised. That leaves many grey areas when physical boundaries dramatically shift and change as a result of flooding or other natural phenomenon.
To gain a better understanding of the potential implications of climate change for maritime borders, it is worth looking at three scenarios. While the specific cases must be considered hypothetical, each of the examples demonstrates that the legal uncertainties caused by climate change could lead to increasing foreign-policy and security problems.
Shifting borders between neighbours
Many of the world’s coastal nations — including China, the US and others — will find that sea-level rise causes a dramatic retreat inland of their coastlines. This can threaten a nation’s territory because in many cases a country’s maritime boundary is determined by its coastline.
Generally speaking, a state is entitled to an exclusive economic zone (EEZ) of 200 miles (322 kilometres) off its coast, unless its zone butts up against the zone of another country, in which case they usually split the difference. For example, if two nations are separated by 100 kilometres of ocean, they often will agree to set their maritime border 50 kilometres from each shore.
This is the case, for example, with the Cuba–US border. The problem is that the US coastline is measured from the Florida Keys, an extremely low-lying region, while Cuba is relatively mountainous and not as likely to lose ground to rising sea levels.
So, leaving the Bahamas aside, if the Keys flood and the Florida coastline retreats up towards the middle of the state, while Cuba stays more or less as it is, should the border be moved to reflect the new mid-point? That would put the entrance to the Gulf of Mexico in Cuban waters and, while southern Florida would be submerged, it still would be an impediment to shipping, meaning that sea traffic would have to loop down through Cuban waters.
Given that the boundary is confirmed bilaterally every two years, there might be a case under international law for Cuba or the US to seek a renegotiation on the ground that reality has changed as a result of sea-level rise. But it is likely to be international politics and security concerns, rather than international law, that will determine whether the boundary changes or not.
The same principle applies to other regions of the world. Political tensions are already at play in the South China Sea, where a slight rise in sea levels could submerge one or two critical offshore islands and be used as a pretext for future boundary disputes.
Dramatically eroded exclusive economic zones
If rising sea levels cause a country’s coastline to retreat inland, should its EEZ retreat by the same amount? The UN Environment Programme (UNEP), the University of Dhaka, the World Bank and others have published a map showing that a 1.5-metre sea-level rise could potentially push Bangladesh’s effective coastline inland by hundreds of kilometers. If so, that could put many of the country’s much needed resources in to the territorial waters of neighbours India and Burma (Myanmar). Or even into international waters.
There is a way for Bangladesh to safeguard its maritime claims against the impact of climate change. Under UNCLOS, a country can claim the waters up to 200 nautical miles off its coastline as its exclusive economic zone. If it is on a continental shelf, the shelf itself, submerged or not, can be used to establish a permanent claim regardless of a retreating coastline. If such a claim were submitted by Bangladesh and accepted, the country’s access to offshore resources would be assured.
There are various schools of thought as to why Bangladesh has not done this – all of them involving politics. But if Bangladesh does not get its claim in by May 2009, the deadline set by UNCLOS, it risks losing its continental-shelf claim, leaving it vulnerable to having its maritime border determined by a shifting coastline.
Threats to sovereignty
Long before the low-lying small island states of the Pacific, Atlantic and Indian oceans sink completely, inhabitants may have to be evacuated as salt water infiltrates groundwater, killing vegetation and leaving those without desalination plants without fresh water.
It is very likely that eventually at least one entire nation — the one mentioned most often is Tuvalu — will have to be completely resettled. But can a nation exist without a physical state? If Tuvalu goes under the sea or is abandoned, will it lose its seat in the UN? Will its EEZ revert to international waters? Will it lose its lucrative “.tv” internet suffix?
Article 1 of the Montevideo Convention on Rights and Duties of States sets out that the following qualifications are necessary for the existence of a state:
• permanent population;
• defined territory;
• government;
• capacity to enter into relations with other states.
This definition itself raises a host of questions. The last two qualifications are relatively easy to maintain, even in exile, assuming other states will continue to recognise the dislocated nation. The first two — a defined territory and a permanent population — are issues that currently are being tackled by other countries. In the South China Sea, for example, China has stationed military outposts on partially submerged atolls and is using that “permanent presence” to claim the surrounding defined, though contested, area.
Similarly, if Tuvalu goes under, could it tether a ship to one of its old islands (or dump enough sea breaks to form a new island on top of an old island), keep a few people resident there and then administer the territory – and its attendant EEZ – through a government-in-exile in another country?
Under international law, nations cannot stake claims based on artificially maintained islands; but in an era of sea walls, artificial beaches and other constructs to ward off rising seas, what constitutes “artificial”? For the people affected, such a solution could provide badly needed revenue through access to resource rights (including fishing, undersea mining, and offshore oil and gas), a voice in international forums and the right to return if the seas eventually recede.
The precedents set by agreed solutions (if accepted) could directly affect the security of nations such as the United Kingdom and the US, which stand to lose the right to operate from some geostrategic bases. For example, the low-lying UK territory of Diego Garcia in the Indian Ocean – used as a base by the US – is threatened by rising seas. If the atoll, in the Chagos archipelago, is lost to the sea, will the UK also lose exclusive access to that crucial tract of ocean and, in the process, lose a valuable bargaining chip with the US?
The UN Convention on the Law of the Sea may not be flexible enough to incorporate the changing physical realities. In any case, however, most of the disputes will be subject more to international politics than to international law. Not long ago, the norm for determining maritime boundaries in Europe was the “cannon shot” rule, in which a state was given the maritime area that could be covered by a cannon shot from its shore. (This is the origin of the three-nautical-mile limit.) The clear implication was that, if you could defend it, you could have it. Unless the challenges created by climate change are addressed soon, in the chaotic future of geographical change, the same principle may be increasingly true again.
Next: Opportunities and tensions in the Arctic
Cleo Paskal is an associate fellow at the Royal Institute of International Affairs (Chatham House) in London.
Her full report on this topic can be found here
Copyright Cleo Paskal, 2007
Homepage photo by darijus
