Oceans

Oceans are very important. They cover 71% of the worlds's surface and, as well as their importance for fishing, trade and transport they play a major role in climatic and environmental stability. They absorb a very high proportion of the C02 we produce and without their absorbtion capacity the world would be heating up much faster. They also transport the heat received from solar radiation from the equatorial belts towards the poles by a series of major currents. This is critical, otherwise there would be a global heat imbalance with equatorial regions heating up and the polar regions getting colder. Britain is a major beneficiary of this process via the Gulf Stream which flows up from the Gulf of Mexico, along the east coast of the USA, then across the Atlantic to the British Isles. This is why the Scilly Isles and Cornwall have Palm trees and other sub-tropical plants. But the Gulf Stream is part of a much bigger system known as the Atlantic conveyor system whereby the warm waters begin to cool and sink as they reach the North Atlantic and Iceland and are transported back at depth towards the equator. There are similar systems in the Pacific and in the Southern Hemisphere including the Humbolt current off Peru which is important for fishing. The Pacific also experiences an alternation of tropical warming and cooling every few years called El Nino and El Nina which causes major changes in weather systems across South america, South Africa, and Australia. In addition to these important climatic elements, warming of the oceans and the atmosphere means that much greater qualities of moisture are being absorbed into the atmosphere and generating more frequent and stronger tropical storms and hurricanes, the tail ends of which are hitting Britain and western Europe causing heavy rainfall and flooding. In addition to all this, seas and oceans support an estimated 60-70 million fishermen and women and the 200 million tons of fish caught annually provides the major source of protein for 2-3 billion people. Last but not least we discuss transport. Some 90% of world trade by weight, though only 70% by value goes by sea - oil and gas, ironore,wheat, soya, timber, cars and container ships. Only the lightest and most valuable cargoes go by air. And when major trade routes are blocked as the Persian Gulf and the Straits of Hormus, then the global economy feels the pinch. The oceans are important.