Unterirdische Jahreszeitenwinde in finnischen Åsern

Abstract

In “Fennia”, Vol. 81, No. 5, 1957, V. Okko describes the phenomenon of a seasonally different underground circulation of air in some eskers in Finland. The slopes of those eskers are covered by a sheet of windblown sand, which isolates the air contained within the eskers and thereby stores the warm air of the summer. On the ridges, on the other hand, there are frequent patches of soil with a gravelly and boulder-like structure, where the air can escape from within; in consequence of that micro-climatic differences are to be observed. The relatively warm air streaming out during the winter is sufficient to keep the snow off those gravelly patches permanently. The corollary are interesting differentiations of the vegetation, so that those eskers are standard examples for the complex influences in landscape ecology.