Mediterranean Sea

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Mediterranean Sea

For centuries, the Mediterranean Sea has been the focal point of western civilization. It is an area rich in history and has played critical roles in the development of shipping and trade, as a resource for feeding growing populations, and as an aid to the spread and mingling of races and cultures.

The Mediterranean began to form about 250 million years ago when the Eurasian and African continental plates began moving toward each other, pinching off the Tethys Sea, an extensive shallow sea that separated Europe and much of Asia from Africa and India. It now has only two outlets, the Straits of Gibraltar and the Bosporus, a narrow strait between the Mediterranean and Black Seas. While the central basin of the Mediterranean reaches depths of several thousand yards, there is a sill under the Straits of Gibraltar that is only 1,970 feet (600 m) below the surface. Through this passageway flows surface water from the Atlantic Ocean.

Since the Mediterranean is situated in one of the world's arid belts, the inputs from precipitation and rivers is far less than the water lost through evaporation. If the straight at Gibraltar were to close due to further plate movements, the Mediterranean would dry up. In fact, data from the Deep Sea Drilling Project, seismic surveys, and fossil analysis have found evidence of salt deposits, ancient river valleys, and fresh water animals, all suggesting that this has occurred at least once. Since the African and Eurasian plates are moving together, this will probably happen again.

Humans can do nothing about this impending geological disaster. There are, however, events that people can influence. Domestic sewage, industrial discharge , agricultural runoff , and oil spills are seriously threatening the Mediterranean, fouling its once clear waters, altering its chemical cycling, and killing its organisms. Along its northern coastline are some of the most heavily industrialized nations in the world, whose industries are destroying nearshore nursery habitats, damaging fisheries. Dams on inflowing rivers reduce the sediment inputs, making coastal erosion a major problem. Shipping, once the hallmark of Mediterranean civilization, releases every manner of waste into the Sea, including oil. Annually, 6 million barrels of oil end up in the Mediterranean. The limited water circulation patterns of the Mediterranean compound this problem as pollutants accumulate.

Today seafood contamination and eye, skin, and intestinal diseases are frequently experienced by coastal residents. Marine mammal and sea turtle populations are threatened by habitat loss and nondegradable pollutants dumped into the waters. Sea grass (Posidonia oceanica ), which provides food and habitat for some 400 species of algae and thousands of species of fish and invertebrates, is disappearing. Nutrient enrichment of the Mediterranean results in large plankton blooms which, combined with destructive fishing practices, contribute to the demise of the sea grass beds.

These problems have been recognized, and efforts are being made to reverse the declining health of the Mediterranean. Early efforts included the 1910 construction of one of the first institutions for study of the seas, the Musée Oceanographique by Prince Albert I of Monaco. Since then, the conflicts between the political and religious ideologies of the 18 nations surrounding the Mediterranean have been major hurdles in completing cleanup plans. In 1976, the Mediterranean Action Plan was signed by 13 of the nations. A major component of this agreement was the Blue Plan, a study of future effects of increasing coastal populations. Other efforts include the Genoa Declaration in 1985 and the Nicosia Charter in 1990. The latter commits resources of the community, the World Bank , the European Investment Bank, and the United Nations Environment Programme to achieve a Mediterranean environment compatible with sustainable development by 2025. Hopefully, these efforts can reverse the decline of this natural wonder.