Beobachtungen und Überlegungen zur eiszeitlichen Depression von Schneegrenze und Strukturbodengrenze in den Tropen und Subtropen

Abstract

The discussion concerning the convergence or divergence of the snow line and boundary of polygonal soils in the sub-tropics is the result of observing forms rather than processes. The same forms may arise from different processes. In the case of the last ice age several depressions of the snow line can be established in the sub-tropics and tropics, although these, however, did not run concurrently. It is necessary to start out from the assumption that the relationship of the snow line position, the permafrost boundary and the polygonal soil boundary was not constant during the late Quaternary, since fluctuations in the hygric climate occurred independently of thermal fluctuations. This holds good for the sub-tropics on the one hand and for the tropics on the other. In this connection attention should be drawn to the problems arising in large areas from reconstructions - frequently attempted - of snow lines and polygonal soil boundaries of the last glacial period, since phenomena of unequal age are employed in these reconstructions.