ABSTRACT
About 75 per cent of the surface of Planet Earth is covered by the oceans and their contiguous seas, in all some 140 million square miles down to depths of 7 miles. ‘Planet Ocean’ might well be seen as a name more apt for our part of the solar system (Figure 6.1). So vast, yet so far removed from the day-to-day lives of the majority of people of the world, the marine environment is viewed by most of mankind as everlasting and something so immense that it is immutable. Its waters bathe the entire planet and its artery-like currents influence the countries which lie within their ‘hinterland’; its freshwater extensions reach into the heart of the human habitat. Despite the ebb and flow of the tide and the exaggerations brought about by storm-induced waves, the oceans and seas remain within well-defined limits.
