Lacustrine Sediments and Tree-Limit Variations as Indicators of Holocene Climatic Fluctuations in Lappland, Northern Sweden

Abstract

In this paper Holocene climatic changes recorded in Lappland, northern Sweden, are described. Recorded changes are dated in three different ways: (1) moraines fronting alpine glaciers are dated licheno- metrically, (2) lacustrine sediments, in which the silt content varies with size fluctuations of a small glacier, are C¹⁴ dated, and (3) variations in altitude of the pine tree limit are C¹⁴ dated. The advantages and limitations of the three techniques are discussed and the results of the studies are compared. In general, the results obtained in these three ways are consistent and are interpreted in climatic terms.

The area around Vuolep Allakasjaure probably became deglaciated just before 9000 B.P. About 8600 B.P. climate began an improvement which culminated between 7000 and 6000 B.P. Shorter fluctuations are superimposed on this long-term climatic change. The most pronounced periods of relatively cold climate occurred about 7500–7300 B.P., 4500 B.P., 2800–2200 B.P., and during recent centuries. Variations in the composition of sediments in cores from Vuolep Allakasjaure indicate that the glacier in the drainage basin fluctuated frequently in size.