NORTH SEA, or GEnxtAN OCEAN Mat. Ger Mare, r. Nord sec, Dan. l'esterh«ret, West Sea ). That part of the Atlantic between the eastern eoast of Great Britain and the Conti nent of Europe (Map: Europe, I) 3). It is pear shaped in general outline, with a wide opening northward into that part of the Atlantic Ocean known as the Norwegian Sea, and with a narrow ing arm extending from the main oval body southward to the Strait of Dover, which, with the English Channel, forms the southern communica tion with the Atlantic. On the east the Skagerrak leads between Jutland and Norway into the Cattegat. which connects through the Sound and the Great and Little Belts with the Baltic Sea. The greatest width of the North Sea, between Dundee, Scotland, and the entrance of the Lim- , fjord in Jutland. is 412 miles; its greatest length from north to south is 680 miles: and its area is , about 201000 square miles, of which 2500 square I miles are occupied by islands. A number of large rivers flow into the southern part of the North Sea; the chief of these are the Elbe, Weser, I Ems. Rhine, which is joined at its mouth IT the Meuse. and Scheldt on the Continent, and the Thames and the Humber in Great Britain. These render the water less saline than that of the main ocean. though the salinity is greater than that of the Baltic, the percentage of salty constituents being 1.025 in the southern part of the sea. They also contribute their sediment to the formation of the numerous shoals and sandbanks which line the southern and southeastern shores. These shores are very low, the land in many places lying below the sea-level. They have been much encroached upon by inundations, which have left the higher portions of the former coast-line as a chain of islands. Behind these are a series of shallow lagoons and inlets, of which the most notable are the Jade (q.v.) in Germany, and the Zuyder Zee (q.v.) in Holland.
In general the depth of the North Sea increases gradually northward. The mean depth of the
southern portion is about 100 feet. near the mid dle it is 230. and in the north 400 feet. Along the steep. rocky coast of Norway there runs a trough with a depth of nearly 1000 feet within 20 miles of the shore. On the other hand, there are in the southern half of the sea, besides the shoals mentioned along the coast, several shallow regions rising considerably above the mean level of the bottom. Among these the Dogger Bank occupies a large portion of the south-central part ; of the sea, with a depth of 00 to 100 feet, the surrounding depths being 150 to 200 feet. The tides of the North Sea are very irregular. owing to the fact that two tidal waves enter it, one I from the north and one from the south. The • former sweeps southward along the west shore, the latter northward along the eastern mast. 'Midway bet wren the shores there SN.111.1 to be very little rise and fall and at some points none at all, while in some places on the southern shore. where the two waves unite, there is a difference of 20 feet between high and low tide. The winds on the North Sea ai-e variable, those from the west. being the most prevalent. Bain and fogs occur at all and the violent northwest storms blowing toward the shoals on the south east coast make navigation Hann- exceedingly dangerous, especially along the coast of Jutland. Nevertheless, owing to its favorable position, the North Sea is one of the most frequented and most important commercial highways of the world. Its fisheries are also among the foremost, provid ing support for many thousand inhabitants of the surrounding countries.
By means of the Kaiser Wilhelm Canal ships can now enter the Baltic Sea without making the passage around Jutland.
Consult: Fulton, "(In the Currents of the North Sea, and Their Relation to Fisheries," Scotland Fishery Board Report for 1806; Haas, Deutsche Nordsre Kiiste, fricsische Ins('ln and Helgoland (Bielefeld, 1900).