INTRODUCTION

Oceans cover about 70 per cent of the Earth's surface, accounting for most of the Earth's water and making up more than 97 per cent of the biosphere. The oceans nurture life and shape the planet's weather and climate. They create more than half of our oxygen and provide vital sources of protein, energy and minerals. As described by some, ‘Earth is a marine habitat’. The oceans provide food for a billion people, and are also a source of income and livelihood for millions. The FAO estimates that about 540 million people are employed in capture fisheries and in related secondary activities.

But oceans are experiencing serious environmental challenges, many of which have unknown consequences. In 1990, a report by the Joint Group of Experts on the Scientific Aspects of Marine Environmental Protection (GESAMP) on the ‘State of the Marine Environment’ highlighted coastal pollution as the principal threat to the marine environment. In 2001, the same group of experts, while recognising that land-based activities continued to be the principal source of pollution, acknowledged that pollution is not the only, or even the most severe, threat to the oceans, and that direct physical damage to ecosystems and habitats and over-exploitation of the resources ‘have even greater worldwide effects’. GESAMP considered that the emergence of new issues, such as global warming, ‘placed the protection of the seas in a new perspective’.