| Abstract: | The alternating retreats and readvances of the North American ice sheet from 18,000 years to 6000 years ago are attributed to shifts in storm tracks. According to the author's theory, proglacial lakes formed during the retreat of the ice sheet became the paths of cyclone tracks whose precipitation led to an accumulation of ice and a readvance of the ice sheet. The readvance into the proglacial lake basins resulted in a reduction or southward shift of cyclone tracks, and this in turn led to a halt of the readvance and a retreat of the ice sheet. As soon as the ice had vacated the Great Lakes basin, the cyclone tracks would once again shift northward and the process of readvance would start all over again. |
