UNCLOS and Climate Change
Redgwell, Catherine, Proceedings of the Annual Meeting-American Society of International Law
Climate change is often described as the most significant environmental challenge of our time. It is a global--and, indeed, a complex, even "super wicked"--problem, the effects of which will be felt far beyond the location at which greenhouse gases (GHG) are emitted, including, of course, upon the oceans. The Intergovernmental Panel on Climate Change (IPCC) has noted that:
Natural systems at risk include glaciers, coral reefs and atolls, mangroves ... and polar and alpine ecosystems.... While some species may increase in abundance or range, climate change will increase existing risks of extinction of some vulnerable species and loss of biodiversity. It is well-established that the geographical extent of the damage or loss, and the number of systems affected, will increase with the magnitude and rate of climate change. (1)
On the global scale, climate change is expected to lead to changes in the distribution of species, including invasive species but also migratory species (with consequences for fisheries management and marine protected areas), and to relationships between predator and prey. Loss of Arctic sea ice threatens biodiversity across an entire biome, with the related pressure of ocean acidification resulting from higher concentrations of carbon dioxide in the atmosphere. (2)
For the oceans, climate change has both direct and multiplier effects on existing challenges for marine species and habitat conservation in particular, and the potential to act synergistically with current anthropogenic threats from coastal development, pollution, and unsustainable fishing practices. These effects include the potentially negative aspects of human responses to climate change such as ocean iron fertilization (OIF), which seeks to enhance plankton growth and absorption by the oceans of carbon dioxide from the atmosphere. The uncertainties and controversies surrounding such geoengineering methods have recently been considered both nationally and internationally, with the international debate over OIF having taken place largely outside UNCLOS, under the 1972 London Convention and 1996 Protocol (LC/LP) and under the 1992 Convention on Biological Diversity (CBD). Nonetheless, the impact of OIF on marine biological diversity has been considered by the UN Ad Hoc Open-Ended Informal Working Group to study issues relating to the conservation and sustainable use of marine biological diversity beyond areas of national jurisdiction and raised in the annual oceans reports by the UN Secretary General, which has served further to focus attention on the issue of OIF. Moreover, the discussion under the LC/LP and CBD has occurred against the legal backstop of the UNCLOS (Article 192) and customary law obligation to protect and preserve the marine environment.
Beyond these environmental impacts is the physical impact of climate change on sea-level rise, and the consequential implications for baselines and, indeed, for the very continued existence of low-lying states such as the Maldives. There is a degree of scientific uncertainty about the extent of rise; the IPCC (3) estimates a (conservative) range of 0.38 to 0.59 meters rise in sea level by 2100. This has particular implications for UNCLOS provisions reliant upon water depth. Perhaps surprisingly, however, there are not many such provisions: one is contained in Article 76(5) on continental shelf delimitation, which makes reference to the depth criterion of the 2500-meter isobath. However, at the water depths of the outer continental shelf, even up to a one-meter rise in sea level would still fall statistically within the error range in standard navigational charts. Even were this not the case, there is the additional point that UNCLOS seeks to provide (future) legal certainty with respect to the outer limits of the continental shelf in providing in Article 76(9) that the "coastal state shall deposit with the Secretary-General of the United Nations charts and relevant information, including geodetic data, permanently describing the outer limits of its continental shelf. …