| Summary: | This thesis investigates Holocene storminess and climate change reconstructed from lacustrine sediments from the Lofoten-Vesterålen archipelago in northern Norway (68–69°N, 12–16°E). The present thesis consists of an introduction and three individual papers in studying different perspectives of aeolian (wind) activity reconstructed from (I) glacier fluctuations, (II) coastal dunefield dynamics and (III) variations in aeolian sand influx from three different lake sediment basins. Paper I presents the first high-resolution late-Holocene glacier record from Lofoten. The study is based on glacial geomorphological mapping and analyses of sediment cores from lake Kveitvikvatnet (30.1 m a.s.l.), which currently receives meltwater from three small cirque glaciers. By combining selected sediment proxies to glacier advances of known ages, a continuous curve of the glaciers equilibrium-line altitude (ELA) over the last 1200 years has been constructed. This has further been connected to an independent proxy for summer temperature using the well-known ‘Liestøl- equation’, as well as the D/A-ratio, resulting in winter precipitation estimates throughout the recorded period. The extremely high sedimentation rates measured in the sediment cores (0.15–0.45 cm/yr) allow us to draw an analogy to instrumental data from nearby meteorological stations, which strongly supports our approach. We have identified that both the Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA) were periods of high glacier activity in Lofoten. It is proposed that the advancing glaciers during both periods were caused mainly by an increase in winter precipitation, in relation to an increase in the strength of the westerlies. In Paper II we investigate the aeolian activity at a coastal dunefield on Andøya in Vesterålen. The study is based on a combination of geomorphological mapping, a lacustrine sediment record from the distal lake Latjønna (14.5 m a.s.l.) and a foredune stratigraphy. The lake sediment record was analysed by high-resolution ...
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