Fróðskaparrit - 01.01.1987, Side 48

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WHEN, HOW, AND WHENCE?
Fig. 1. The movements of the polar front from 14000 BP to the present. Figures given are years BP. The front retre-
ated northwards after its extreme position in the south and has been recorded off southern Greenland at 11000 BP
(filled circle). During the Younger Dryas it advanced southwards again and reached its southern limit at 10200 BP,
when the North Atlantic for a short period returned to glacial conditions. A warming then occurred and at 9300 BP
the front was again situated off southern Greenland. The extreme interglacial position of the front is also shown (0
BP). The arrow indicates that the polar front was situated off Cape Finisterre at about 14000 BP. Note that the coast
lines are the current ones. (Redrawn after Ruddiman et al. 1977).
The North Atlantic Drift probably penetrated between the British Isles and Iceland during its first retreat, but was
again shut off from the North Atlantic during the Younger Dryas. After this short glacial spell the Drift returned
northwards again, but was turned back on itself at about the level of Iceland (see Fig. 2).