C. A. M. Taber

“ As the western continent is the only land that extends unbroken from the equator to the cold latitudes of both hemispheres, thus affording an opportunity for the prevailing winds to move the tropical waters into the high latitudes, I will call attention to that portion of the continent which extends far southward into the southern ocean, where the winds and ocean currents have the greatest range and power to affect the climate on different parts of the globe. ”

“ For, when we realise how the facilities for making ice have advanced through the increase of glaciers in both hemispheres, and how large a portion of the ocean waters have been cooled below a temperate or tropical temperature even in the torrid latitudes where the warm upper waters of the ocean have been reduced to a comparatively thin stratum when compared to the vast bulk of the cooled under-waters, it appears that the cold will increase at a faster rate for the next thousand years than was the case during the last ten centuries. ”

“ While regarding the circulation of the sea during an ice age, it may be said that the ocean’s being composed of brine was the cause of its waters being able to circulate in frigid latitudes where fresh water would congeal. Consequently, this is one of the reasons why successive periods of frigidity and mildness have been brought about; for with an ocean of fresh water, repeated epochs of cold and warmth could not have occurred, because a sea composed of fresh water would have congealed while circulating in the high latitudes during a frigid age. ”

“ Its steep ravines, which deepen as they approach the sea, recall to the southern voyager the ice-worn islands of the high latitudes. It seems improbable that these deep ravines which penetrate the hard volcanic rock, on their short course to the sea, could have been caused by their scanty brooklets.
The bowlders scattered over the island are not in harmony with the weathering process, while the obliteration of its craters seems to point to a more rapid process of erosion than could be attributed to weathering. ”

“ Moreover, when we consider that the independent circulation of the southern ocean is caused by the westerly winds blowing its surface waters constantly around the globe through the open Cape Horn channel, and so largely preventing the tropical currents from entering the high southern latitudes, and how, in consequence, the cold is slowly on the increase through the constant accumulation of ice on the lands and in seas of the southern latitudes, it appears that a frigid age is slowly progressing in the southern hemisphere. ”

“ Although the coast ranges differ from the Sierras in their make up, yet it does not disagree with the glacial origin of the former inferior mountains, from the fact that the ice-sheets, while moving their bulk westward, displaced the deposits of such bays, lakes, rivers, and marshes as lay abreast of the Sierra slopes. The advancing ice-sheets, thousands of feet in depth, moving from a lofty and steep incline, pressed and ploughed below the somewhat superficial cretaceous and alluvial strata which lay in their course. ”

“ The inurement to cold acquired by animals during the glacial age is still an attribute possessed by many species of fauna to-day. For, when a warm climate took possession of the tropical zone, it was deserted by a large portion of the animals that found refuge there during the glacial age. ”

“ Such parts of Southern Europe and Northern Africa as bordered on the Mediterranean Sea probably possessed a milder climate during the ice age than regions in the same latitudes on the Atlantic coast, for the reason that the North Atlantic was proportionally a greater receptacle for icebergs which were launched into it from the numerous glaciers of North-eastern America, Greenland, Iceland, and North-western Europe than the great inland sea obtained from its less frigid shores. ”

“ Several years ago a correspondent of the Spectator, writing from Northern Russia where the Volga is locked with ice for six months in the year, stated that “the people were beginning to show increased resentment at the climate, and that there was reason to believe that the northern government of Russia would be abandoned to the desert. The people silently glide south by the tens of thousands every year, so the life of Russia was concentrating in the south.” ”

“ A glacier three thousand feet thick would fill and press heavily on the bottom of a gorge fifteen hundred feet in depth. Therefore, should the bottom of a fiord sink hundreds of feet below the sea-level, a glacier several thousand feet thick flowing through and over it into a sea of much greater depth, the erosion at the bottom of the sunken channel would be greater than on the land above the sea, where the ice possessed less weight. ”

“ Therefore, the high and low sea-levels caused by such winds would be greater on a shallow ocean than would occur on deeper waters. Thus the low sea-levels of the shallow southern sea would have strong attraction for tropical surface waters, and so increase the thickness of its warm drift currents, and at the same time its lessened depths would have less capacity for the storage of cold water to reduce the temperature of the under-waters of the tropical zone. ”

“ Thus from such parts of the coast only the largest bergs, which require a deep sea to float them, are moved by the under-currents into the temperate latitudes. Therefore, it happens that, while an ice period progresses, and the antarctic icebergs increase in size, the more readily the cold, deep under-currents force them into the temperate zone, in opposition to the winds and surface currents. ”

“ And here the frigidity stored up in the glaciers of the higher latitudes was set free, thus chilling the waters as well as the atmosphere of that region. The Alpine flora of the American coast mountains was probably carried by floating ice to the Galapagos, while its rookeries of albatross and seal date back to a cold period. And it seems that these cold-weather animals, with the assistance of the cool Humboldt current, may be able to preserve their rookeries at the equator until the advent of another ice period. ”