BLACK SEA

Russian and Bulgarian Chernoye More, Ukrainian Chorne More, Turkish Karadeniz, Romanian Marea Neagra, large inland sea situated at the southeastern extremity of Europe. It is bordered by Ukraine to the north, Russia to the northeast, Georgia to the east, Turkey to the south, and Bulgaria and Romania to the west. The Black Sea. The roughly oval-shaped Black Sea occupies a large basin strategically situated at the southeastern extremity of Europe but connected to the distant waters of the Atlantic Ocean by the Bosporus (which emerges from the sea's southwestern corner), the Sea of Marmara, the Dardanelles, the Aegean Sea, and the Mediterranean Sea. The renowned Crimean Peninsula thrusts into the Black Sea from the north, and just to its east the narrow Kerch Strait links the sea to the smaller Sea of Azov. The Black Sea coastline is otherwise fairly regular. The maximum east-west extent of the sea is about 730 miles (1,175 kilometres), while the shortest distance between the tip of the Crimea and the Kerempe Burmi Cape to the south is about 160 miles. The surface area, excluding the Sea of Marmara but including the Sea of Azov, is about 178,000 square miles (461,000 square kilometres); the Black Sea proper occupies about 163,000 square miles (422,000 square kilometres). A maximum depth of more than 7,250 feet (2,210 metres) is reached in the south-central sector of the sea. In ancient Greek myths, the seathen on the fringe of the Mediterranean worldwas named Pontus Axeinus, meaning Inhospitable Sea. Later explorations made the region more familiar, and, as colonies were established along the shores of a sea the Greeks came to know as more hospitable and friendly, its name was changed to Pontus Euxinus, the opposite of the earlier designation. It was across its waters that Jason and the Argonauts set out, according to legend, to find the Golden Fleece in the land of Colchis, a kingdom at the sea's eastern tip (now Georgia). The Turks, when they came to control the lands beyond the sea's southern shores, encountered only the sudden storms whipped up on its waters and reverted to a designation reflecting the inhospitable aspect of what they now termed the Karadeniz, or Black Sea. To scientists the Black Sea is a remarkable feature because its lower levels are, to all intents and purposes, almost biologically deadnot because of modern pollution but because of continued weak ventilation of the deep layers. To the nations of the region, the Black Sea has been of immense strategic importance over the centuries; the advent of more settled conditions has brought its economic importance to the fore. Russian and Bulgarian Chernoye More, Ukrainian Chorne More, Turkish Karadeniz, Romanian Marea Neagra large inland sea situated at the southeastern extremity of Europe. It is bordered by Ukraine to the north, Russia to the northeast, Georgia to the east, Turkey to the south, and Bulgaria and Romania to the west. The Black Sea is connected to the distant waters of the Atlantic Ocean by the succession of the Bosporus (a strait at the Black Sea's southwestern corner), the Sea of Marmara, the Dardanelles, the Aegean Sea, and the Mediterranean Sea. The peninsula of Crimea extends into the sea from the north, and immediately to the east the narrow Kerch Strait opens onto the smaller Sea of Azov. The Black Sea's water-surface area is about 178,000 square miles (461,000 square km), and its maximum depth is more than 7,250 feet (2,210 m). The Black Sea has few coastal lowlands. The Danube, Dnieper, Dniester, and Don are the largest rivers emptying into the sea. The Black Sea is a residual basin of the ancient Tethys Sea; its present form probably emerged about 58 million years ago when structural upheavals in Anatolia split off the Caspian basin from the Mediterranean. The newly formed Black Sea basin gradually became isolated from the ocean, its salinity was reduced, and it was slowly separated from the Caspian region. The salinity of the Black Sea is almost half that of the world's oceans. An unusual feature of the Black Sea is that oxygen is dissolved only in the upper levels of its waters, which alone can support a rich sea life as a result. Below a depth of 230330 feet (70100 m) at the centre and 330500 feet (100150 m) near the sea's margins, there is no oxygen because the sea is permeated by a high concentration of dissolved hydrogen sulfide, forming a saturated, dead zone inhabitable only by specially adapted bacteria. Despite this anomaly, the Black Sea's uppermost waters supported abundant sturgeon, mackerel, and anchovy until the late 20th century, when the runoff of industrial and municipal wastes into the Danube, Dnieper, and other feeder rivers caused increasing levels of pollution and consequent reductions in fish populations. The Black Sea remains an important shipping artery linking Ukraine, Bulgaria, Romania, and southwestern Russia with world markets. The sea's northern coast, particularly the Crimea, is a major recreational area for eastern European vacationers. Additional reading Little is written on the Black Sea in English. L.A. Zenkevich, The Black Sea, in his Biology of the Seas of the U.S.S.R., chapter 9 (1963; originally published in Russian, 1963), is dated but still useful. More recent texts include Iu.I. Sorokin, Chernoe More: priroda, resursy (1982), on the nature and resources of the sea; A.I. Riabinin and V.N. Kravets, Sovremennoe sostoianie serovodorodnoi zony Chernogo Moria: 19601986 gody (1989), containing scholarship on the hydrogen sulfide content of the deep waters; Egon T. Degens and David A. Ross (eds.), The Black SeaGeology, Chemistry, and Biology (1974); and D. Tolmazin, Changing Coastal Oceanography of the Black Sea, Progress in Oceanography, 15(4):217316 (1985). Aleksey Nilovich Kosarev