1 5 Ju l 2 00 4 A link between an ice age era and a rapid polar shift

نویسندگان

  • W. Woelfli
  • W. Baltensperger
چکیده

The striking asymmetry of the ice cover during the Last Global Maximum suggests that the North Pole was in Greenland and then rapidly shifted to its present position in the Arctic See. A scenario which causes such a rapid geographic polar shift is physically possible. It involves an additional planet, which disappeared by evaporation within the Holocene. This is only possible within such a short period, if the planet was in an extremely eccentric orbit and hot. Then, since this produced an inter-planetary gas cloud, the polar shift had to be preceded by a cold period with large global temperature variations during several million years. In the Last Global Maximum the ice cover on the North American continent reached the region of present New York and in Europe of North Ger-many, while East Arctic Siberia was ice free. This well known asymmetry is corroborated by current research. The palaeolithic Yana RHS site [1] at 71 • N, well inside the polar circle, was populated 27 000 years ago. This is referred to as " A surprising survival story " [2]. Alternatively, the site is an indication that the climate in that region was mild. Clearly, the Sun was not warmer since on the North American continent the climate was cold. In arctic Siberia, a mild climate could only result from lower latitude. The postulate of a geographic polar shift is more than a century old. The striking asymmetry of the ice cover on the northern hemisphere in the Last Global Maximum would disappear, if the north pole had then been situated within Greenland, shifted by about 18 • from its present position in the Arctic Ocean [3]. Considering this shift, the Yana RHS site would have a position of about 53 • N, appropriate for hunting and living all year round. Of course, other regions also experienced changes. For instance in the Amazon palaeo sand dunes have been found at the Equator [4]. Before the shift, these were at a latitude of about 18 • N, which crosses the present Sahara desert. The assumed turn of the globe similarly explains climate changes of many regions. Since the South Pole remained within Antarctica, the resulting climate changes on the southern hemisphere were less spectacular. How can a polar shift arise? The shape of the rotating Earth is determined by hydrostatic equilibrium ; the Earth has a slight bulge along the Equator. …

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تاریخ انتشار 2008