PHYSIOGRAPHY OF THE See also:

• ARCTIC (Gr. "ApKroc, the Bear, the northern constellation of Ursa Major)

Cretaceous and See also:

• TERTIARY

The existence of raised sea margins in many Arctic lands and especially in the American Arctic archipelago bears evidence to a See also:

• RECENT

The most valuable records and practically the only data available for the climate north of 84° are those of the first expedition of the " Fram " in her three years' See also:

• DRIFT (from "drive ")

134° 17' E. The minimum temperatures recorded on See also:

• SIR

9'4 -15.3 -26.0 -42 February. — 6.7 -14.5 —z6'5 -42 March. . -I- 3.0 — 8.3 -23.1 -31 April . 19.0 + 6.8 — 8.9 -18 May 34'7 24.1 +14'9 + 9 June 48'6 37.9 30.0 28 July . 45.0 35.6 30 August . 50.6 43.2 32'7 27 See also:

• SEPTEMBER (Lat. septem, seven)

Extraordinarily rapid See also:

• VARIATIONS
• VARIATIONS, CALCULUS
• VARIATIONS, CALCULUS OF

Cyclonic depressions crossed the region of the " Fram's " track with considerable frequency, 73 being experienced in the three years, the frequency being greatest in winter but the wind velocity in cyclones greatest in summer; the most See also:

• COMMON

The cold of winter is not sufficient to put a stop to plant See also:

• LIFE

Arctic See also:

• PEOPLE

The Greenland Eskimo are the most typical and the best known of their race. A few See also:

• HUNDRED

The area of the Arctic Sea may be estimated to be about 3,600,000 sq. m., of which nearly two-thirds (or 2,300,000 sq..tn.) is continuously covered by floating ice. The Arctic Sea may be divided into the following parts: (1) The North Polar Basin (including the Siberian Sea), bounded by the northern coasts of Siberia (from Bering Strait to the western Taimyr Peninsula), Franz Josef Land, Spitsbergen, Greenland, See also:

• GRINNELL

The depth of the shelf is, especially north of Siberia, very See also:

• UNIFORM

The Norwegian Sea, farther south, is 2000 fathoms deep midway between Iceland and Norway, in about 68° N. This so-called Norwegian deep is, as before stated, separated from the North Atlantic Basin by the Wyville See also:

• THOMSON, JAMES (1822-1892)
• THOMSON, JAMES (1834-1882)
• THOMSON, JAMES (r700-1748)
• THOMSON, JOHN (1778-184o)
• THOMSON, JOSEPH (1858-1895)
• THOMSON, SIR CHARLES WYVILLE (1830-1882)
• THOMSON, THOMAS (1773-1852)
• THOMSON, WILLIAM (1819-189o)

The currents in this sea may to some extent be considered as convection currents, caused by the cooling of the water near the surface, which becomes heavier, sinks, and must be replaced on the surface by warmer water coming from the south, which is also influenced by the prevailing winds. On account of the rotation of the earth the northward-See also:

• RUNNING

3. An Atlantic current runs northward along the west coast of Greenland, passes the ridge across Davis Strait, and flows into Baffin Bay, forming its deeper strata below the polar water in a similar way to the Gulf Stream in the North Polar Basin. There is a possibility that some slight portion of this current even reaches the latter along the bottom of the deep channel through Smith Sound. 4. A small current running northward into the North Polar Basin through Bering Strait. The Arctic Sea receives also a contribution of fresh water from the rivers of northern Europe, Siberia and America, as well as from the glaciers of Greenland and the precipitation over the whole area of the sea itself. The chief currents running out of the Arctic Sea are: (r) The Greenland Polar Current, running southward along the east coast of Greenland, and dividing into two branches north of Iceland—(a) the east Greenland branch, passing south through Denmark Strait and rounding Cape Farewell; (b) the east Iceland branch, running south-eastward between Iceland and Jan Mayen, towards the Faeroes. It seems as if only a small portion of this current actually passes the Faero-Iceland ridge and reaches the Atlantic Ocean. The greater part is partly mixed with the water of the Gulf Stream and is turned by the latter in a north-easterly direction, forming a kind of eddy or vortex movement in the southern Norwegian Sea. (2) The Labrador Polar Current, formed by the water running south through Smith Sound, Lancaster Sound and Jones Sound, as well as water from Baffin Bay, and also from the east Greenland current rounding Cape Farewell and See also:

• CROSSING

Temperature and Salinity.—While the temperature is comparatively uniform, with small variations, the difference in salinity between the upper and lower strata is greater than in most other parts of the ocean. In the North Polar Basin the vertical distribution of temperature as well as salinity is very much the same in all places examined. Near the surface, from o down to roo fathoms, the water is below the freezing point of fresh water—with a minimum of between 28.7° (-1.8° C.) and 28.6° (-1.9° C.) at a depth of about 30 fathoms—and is much diluted with fresh water (see above), the salinity gradually increasing downward from about 29 or 30 per mille near the surface to nearly 35 per mille in roo fathoms. Below 100 fathoms the temperature as well as the salinity gradually increases, until they approach their maximum in about 16o or 200 fathoms, where the temperature varies between 32.5° (0.3° C.), north of the New Siberia Islands, and about x,3.8° (r° C.) north of Franz Josef Land; and the salinity is about 35.1 per mille. From this depth the temperature gradually sinks downward; 32° (0° C.) is found at about 490 fathoms in the western part of the basin—e.g. between about 84° N. 15° E. and 851° N. 58° E., while it is found in about 400 fathoms farther east—e.g. in 812° N. and 123° E. In depths between 1400 and 1600 fathoms the temperature has a second minimum between 3o•6° (-o.8° C.) and 30.4° (-0.9° C.), below which depth the temperature again rises slowly, a few tenths of a degree towards the bottom. In all depths below 200 fathoms the salinity of the water remains very much the same, about 35.1 per mille, with very slight variations. This comparatively warm and saline water evidently originates from the branch of the Gulf Stream passing north across the submarine ridge from north-west Spitsbergen. The vertical distribution of temperature and salinity is very much the same, summer and winter, throughout the North Polar Basin, except water much diluted by the fresh water from the Siberian rivers near the surface, which in summer is covered by a layer of fresh water arising from the melting of the snow-covered surface of the See also:

• FLOE (of uncertain derivation; cf. Norse flo, layer, level plain)

North of the Siberian coast the sea is, during summer, covered with a layer of warm water from the Siberian rivers, and the temperature of the surface may rise to several degrees above freezing-point. In the Norwegian and Greenland Seas there are greater variations of temperature. Below a certain limit, which in the northern part (on the eastern side) is about 550 fathoms deep, and in the southern part between 300 and 400 fathoms deep, the whole basin of this sea is filled with water which has an unusually uniform salinity of about 34.92 per mille, and the temperature of which is below zero centigrade, gradually sinking downward from the above-mentioned limit, where it is 32° (0° C.); and down to 29.8° (—1.2° C.) or 29.6° ( -1.30 C.) near the bottom in 1400 or r600 fathoms. This cold underlying water of such a remarkably uniform and comparatively low salinity is formed chiefly in a small area between Jan Mayen and Spitsbergen, by the formation of ice and cooling down of the Atlantic surface water by See also:

• RADIATION, THEORY OF

This warmer undercurrent is a continuation of the warm Spitsbergen current sending off a branch westward from Spitsbergen, and thus forming a great vortex movement in the Spitsbergen-Greenland Sea similar to the one mentioned farther south in the Norwegian Sea. In Barents Sea the temperature and salinity are highest in the western part near Norway or between Norway and Bear Island, where the eastern branch of the Gulf Stream enters and where in summer the salinity generally is between 34.8 and 35 per mille from the surface down to the bottom, and the surface temperature generally is about 41° or 43° (50 C. or 6° C.), and the bottom temperature is above zero centigrade. The eastern part of Barents Sea is filled with water of a little lower salinity, the deeper strata of which are very cold, with temperature even as low as 28.9° (—1.7° C.),.but often with salinity above 35.0 per mille. This cold and saline water is formed during the formation of ice on the sea-surface. The bottom temperature is every-where in the eastern part below zero centigrade and generally below -1° C. The Kara Sea is covered near the surface with a layer of cold especially the Ob and the See also:

• YENISEI

These pieces of See also:

• GLACIER
• GLACIER (adopted from the French; from glace, ice, Lat. glacies)

Such a drift of an ice-floe from the sea north of Bering Strait to the east coast of Greenland probably takes, as a rule, four or five years, and the floes found in this part of the sea are not, therefore, generally older. What the drift of the ice is on the American side of 'the North Polar Basin is still little known. But there it is probably more or less blocked up in its southward movement by the islands of the American Arctic archipelago, and the ice-floes may thus grow very old and thick. Commander Peary found a strong easterly movement of the floes in the region north of Grant Land in 1907. The southward distribution of the drifting floe-ice (the See also:

• PACK (apparently from the root pak-, paq-, seen in Lat. pangere, to fasten; cf. " compact ")
• PACK, OTTO VON (c. 1480-1537)

At the same time the temperature of the water rises, and thus the conditions for the chemical changes of matter and nutritive assimilation are much improved. The Arctic Sea, more especially the North Polar Basin, might thus be considered as a See also:

• LUNG

G. Nathorst geleiteten schwedischen Polarexpedition 1898," Kongl. svenska See also:

• VET

Helland-Hansen and E. Koefoed, Hydrographie. (H. R. M.; F.