The new Helsinki Convention on the Protection of the Marine Environment of the Baltic Sea Area

With a marine area of about 415 000 km 2, the Baltic Sea is the largest body of brackish water in the world. It is a semi-enclosed sea connected by the Danish Straits with the North Sea. Nine countries share the Baltic: Sweden and Finland to the North; Russia, Estonia, Latvia, and Lithuania to the East; Poland to the South; and Germany and Denmark to the West. About 80 million people live in its catchment area, including the Peoples of the Slovak Federal Republic, Norway, Ukraine, and part of Belarus. The Baltic Sea is divided into a series of basins of various depths separated by shallow areas or sills. The renewal of the whole body of water in the Baltic takes between 25-30 yr. The Baltic has stratified waters. Its surface waters contain low salinity, its deeper waters contain higher salinity, and the water closest to the bottom is most saline. Its frequent renewal of bottom water influences its oxygen consumption. If oxygen is totally consumed, anoxic conditions are created that lead to the formation of poisonous hydrogen sulphide. The Baltic Sea already contains a totally dead area of 100 000 km ~ in the Gulf of Finland, in the Baltic Proper, the Belt Sea, and the Kattegat. The fact that the Baltic Sea is almost entirely covered by ice in winter exacerbates these anoxic conditions. In addition to these natural problems, rivers flowing to the Baltic Sea carry with them a number of pollutants.