Polar Wandering and Climate*
Abundant evidence from many fields indicates very strongly that the Arctic Ocean was ice- free during the Wisconsin glacial stage, and it is postulated that the ice-free condition of the ocean is directly responsible for the glacial stage. It is shown that the oscillations between ice- free and ice-covered states of the Arctic Ocean which could occur, would account for the al-ternations of Pleistocene climate.
Although the Pleistocene climate oscillations of the northern hemisphere produced simul-taneous oscillations in the southern hemisphere, it is concluded that the Antarctic ice cap persisted without major change through the Pleistocene.
The transition from the climate of the early Tertiary to that of the Pleistocene, as typified by the cooling of Western North America which began in the Oliogocene Epoch, is attributed to a shift of the geographic poles from oceanic positions to their present thermally isolated positions. This shift is discussed in the light of paleomagnetic and paleobiological data.
Figures & Tables
Polar Wandering and Continental Drift
This volume was an early classic during the controversial years before the general acceptance of plate tectonic theory began its rise to the forefront of global geology. The idea of continental drift was originally proposed by A L Wegener, Origin of Continents and Oceans (Braunschweig, 1922) in connection with his analysis of the origin of continents and oceans as a method to help explain anomalous distributive patterns of ancient climate zones [(Koppen-Wegener, Die Klimate der geologischen Vorzeit Borntraeger, Berlin 1924.)] The implications of this proposal seriously challenged many of the beliefs and theories of the constitution of the earth its physical properties tectonics and biologic developments. As a result a considerable furor of opposition arose on all counts but in particular the geophysicists alleged that drift was out of the question because the crust could not endure such forces. Others denied the need for moving the continents to explain either mountain chains or animal and plant disposition in space and time relationships. It has been attempted here to interpret the evidence in terms of two possible mechanisms a) Continental Drift and b) Polar Wandering.