The line of perpetual snow may naturally be expected to descend lower and lower on advancing to the pole, and hence many mountainous regions or elevated plateaux, such as the interior of Spitzbergen, of Greenland, of Nova Zembla, etc., which in a more temperate clime would be verdant with woods or meadows, are here covered with vast fields of ice, from which frequently glaciers descend down to the verge of the sea. But even in the highest northern latitudes, no land has yet been found covered as far as the water’s edge with eternal snow, or where winter has entirely subdued the powers of vegetation. The reindeer of Spitzbergen find near 80° N. lichens or grasses to feed upon; in favorable seasons the snow melts by the end of June on the plains of Melville Island, and numerous lemmings, requiring vegetable food for their subsistence, inhabit the deserts of New Siberia. As far as man has reached to the north, vegetation, when fostered by a sheltered situation and the refraction of solar heat from the rocks, has everywhere been found to rise to a considerable altitude above the level of the sea; and should there be land at the North Pole, there is every reason to believe that it is destitute neither of animal nor vegetable life. It would be equally erroneous to suppose that the cold of winter invariably increases as we near the pole, as the temperature of a land is influenced by many other causes besides its latitude. Even in the most northern regions hitherto visited by man, the influence of the sea, particularly when favored by warm currents, is found to mitigate the severity of the winter, while at the same time it diminishes the warmth of summer. On the other hand, the large continental tracts of Asia or America that shelve toward the pole have a more intense winter cold and a far greater summer’s heat than many coast-lands or islands situated far nearer to the pole. Thus, to cite but a few examples, the western shores of Nova Zembla, fronting a wide expanse of sea, have an average winter temperature of only -4°, and a mean summer temperature but little above the freezing-point of water (+36½°), while Jakutsk, situated in the heart of Siberia, and 20° nearer to the Equator, has a winter of -36° 6’, and a summer of +66° 6’.
The influence of the winds is likewise of considerable importance in determining the greater or lesser severity of an Arctic climate. Thus the northerly winds which prevail in Baffin’s Bay and Davis’s Straits during the summer months, and fill the straits of the American north-eastern Archipelago with ice, are probably the main cause of the abnormal depression of temperature in that quarter; while, on the contrary, the southerly winds that prevail during summer in the valley of the Mackenzie tend greatly to extend the forest of that favored region nearly down to the shores of the Arctic Sea. Even in the depth of a Siberian winter, a sudden change of wind is able to raise the thermometer from a mercury-congealing cold to a temperature above the freezing-point of water, and a warm wind has been known to cause rain to fall in Spitzbergen in the month of January.
The voyages of Kane and Belcher have made us acquainted with the lowest temperatures ever felt by man. On Feb. 5, 1854, while the former was wintering in Smith’s Sound (78° 37’ N. lat.), the mean of his best spirit-thermometer showed the unexampled temperature of -68° or 100° below the freezing-point of water. Then chloric ether became solid, and carefully prepared chloroform exhibited a granular pellicle on its surface. The exhalations from the skin invested the exposed or partially clad parts with a wreath of vapor. The air had a perceptible pungency upon inspiration, and every one, as it were involuntarily, breathed guardedly with compressed lips. About the same time (February 9 and 10, 1854), Sir E. Belcher experienced a cold of -55° in Wellington Channel (75° 31’ N.), and the still lower temperature of -62° on January 13, 1853, in Northumberland Sound (76° 52’ N.). Whymper, on December 6, 1866, experienced -58° at Nulatto, Alaska (64° 42’ N.).
Whether the temperature of the air descends still lower on advancing toward the pole, or whether these extreme degrees of cold are not sometimes surpassed in those mountainous regions of the north which, though seen, have never yet been explored, is of course an undecided question: so much is certain, that the observations hitherto made during the winter of the Arctic regions have been limited to too short a time, and are too few in number, to enable us to determine with any degree of certainty those points where the greatest cold prevails. All we know is, that beyond the Arctic Circle, and eight or ten degrees farther to the south in the interior of the continents of Asia and America, the average temperature of the winter generally ranges from -20° to -30°, or even lower, and for a great part of the year is able to convert mercury into a solid body.
It may well be asked how man is able to bear the excessively low temperature of an Arctic winter, which must appear truly appalling to an inhabitant of the temperate zone. A thick fur clothing; a hut small and low, where the warmth of a fire, or simply of a train-oil lamp, is husbanded in a narrow space, and, above all, the wonderful power of the human constitution to accommodate itself to every change of climate, go far to counteract the rigor of the cold.
After a very few days the body develops an increasing warmth as the thermometer descends; for the air being condensed by the cold, the lungs inhale at every breath a greater quantity of oxygen, which of course accelerates the internal process of combustion, while at the same time an increasing appetite, gratified with a copious supply of animal food, of flesh and fat, enriches the blood and enables it to circulate more vigorously. Thus not only the hardy native of the north, but even the healthy traveller soon gets accustomed to bear without injury the rigors of an Arctic winter.
“The mysterious compensations,” says Kane, “by which we adapt ourselves to climate are more striking here than in the tropics. In the Polar zone the assault is immediate and sudden, and, unlike the insidious fatality of hot countries, produces its results rapidly. It requires hardly a single winter to tell who are to be the heat-making and acclimatized men. Petersen, for instance, who has resided for two years at Upernavik, seldom enters a room with a fire. Another of our party, George Riley, with a vigorous constitution, established habits of free exposure, and active cheerful temperament, has so inured himself to the cold, that he sleeps on our sledge journeys without a blanket or any other covering than his walking suit, while the outside temperature is -30°.”
10. ARCTIC CLOTHING.
There are many proofs that a milder climate once reigned in the northern regions of the globe. Fossil pieces of wood, petrified acorns and fir-cones have been found in the interior of Banks’s Land by M’Clure’s sledging-parties. At Anakerdluk, in North Greenland (70° N.), a large forest lies buried on a mountain surrounded by glaciers, 1080 feet above the level of the sea. Not only the trunks and branches, but even the leaves, fruit-cones, and seeds have been preserved in the soil, and enable the botanist to determine the species of the plants to which they belong. They show that, besides firs and sequoias, oaks, plantains, elms, magnolias, and even laurels, indicating a climate such as that of Lausanne or Geneva, flourished during the miocene period in a country where now even the willow is compelled to creep along the ground. During the same epoch of the earth’s history Spitzbergen was likewise covered with stately forests. The same poplars and the same swamp-cypress (Taxodium dubium) which then flourished in North Greenland have been found in a fossilized state at Bell Sound (76° N.) by the Swedish naturalists, who also discovered a plantain and a linden as high as 78° and 79° in King’s Bay—a proof that in those times the climate of Spitzbergen can not have been colder than that which now reigns in Southern Sweden and Norway, eighteen degrees nearer to the line.