As is to be expected, the large islands in the Polar Sea north of Europe and Asia are, to a great extent, covered with névé-fields, and numerous glaciers push out from them to the sea in all directions, discharging their surplus ice as bergs, which float away and cumber the waters with their presence in many distant places.
Fig. 8.—The Svartisen Glacier on the west coast of Norway, just within the Arctic circle, at the head of a fiord ten miles from the ocean. The foot of the Glacier is one mile wide, and a quarter of a mile back from the water. Terminal moraine in front. (Photographed by Dr. L. C. Warner.)
The island of Spitzbergen, in latitude 76° to 81°, is favourably situated for the production of glaciers, by reason both of its high northern latitude, and of its relation to the Gulf Stream, which conveys around to it an excessive amount of moisture, thus ensuring an exceptionally large snow-fall over the island. The mountainous character of the island also favours the concentration of the ice-movement into glaciers of vast size and power. Still, even here, much of the land is free from snow and ice in summer. But upon the northern portion of the island there is an extensive table-land, upwards of two thousand feet above the sea, over which the ice-field is continuous. Four great glaciers here descend to tide-water in Magdalena Bay. The largest of these presents at the front a wall of ice seven thousand feet across and three hundred feet high; but, as the depth of the water is not great, few icebergs of large size break off and float away from it.
Nova Zembla, though not in quite so high latitude, has a lower mean temperature upon the coasts than Spitzbergen. Owing to the absence of high lands and mountains, however, it is not covered with perpetual snow, much less with glacial ice, but its level portions are “carpeted with grasses and flowers,” and sustain extensive forests of stunted trees.
Franz-Josef Land, to the north of Nova Zembla, both contains high mountains and supports glaciers of great size. Mr. Payer conducted a sledge party into this land in 1874, and reported that a precipitous wall of glacial ice, “of more than a hundred feet in height, formed the usual edge of the coast.” But the motion of the ice is very slow, and the ice coarse-grained in structure, and it bears a small amount only of morainic material. So low is here the line of perpetual snow, that the smaller islands “are covered with caps of ice, so that a cross-section would exhibit a regular flat segment of ice.” It is interesting to note, also, that “many ice-streams, descending from the high névé plateau, spread themselves out over the mountain-slopes,” and are not, as in the Alps, confined to definite valleys.
Iceland seems to have been properly named, since a single one of the snow-fields—that of Vatnajoküll, with an extreme elevation of only six thousand feet—is estimated by Helland to cover one hundred and fifty Norwegian square miles (about seven thousand English square miles), while five other ice-fields (the Langjoküll, the Hofsjoküll, the Myrdalsjoküll, the Drangajoküll, and the Glamujoküll) have a combined area of ninety-two Norwegian or about four thousand five hundred English square miles. The glaciers are supposed by Whitney to have been rapidly advancing for some time past.
In Asia.—Notwithstanding its lofty mountains and its great extent of territory lying in high latitudes, glaciers are for two reasons relatively infrequent: 1. The land in the more northern latitudes is low. 2. The dryness of the atmosphere in the interior of the continent is such that it unduly limits the snow-fall. Long before they reach the central plateau of Asia, the currents of air which sweep over the continent from the Indian Ocean have parted with their burdens of moisture, having left them in a snowy mantle upon the southern flanks of the Himalayas. As a result, we have the extensive deserts of the interior, where, on account of the clear atmosphere, there is not snow enough to resist continuously the intense activity of the unobstructed rays of the sun.