‘Little Ice Age’ nivation activity in northeast Greenland
1998
Christiansen, Hanne H.
During the ‘Little Ice Age’ (LIA), the periglacial landscape in northeast Greenland responded rela tively quickly to the climatic deterioration with increased nivation activity. Resulting nivation landforms and associated sediment basins are used as palaeoclimatic archives, documenting the significant geomorphological effect of nivation during the LIA period in the Zackenberg area. A nival basin studied in detail showed the onset and dominance of niveo-fluvial sedimentation in the period ad 1250–1420, followed by increasing niveo-aeolian sedimentation between ad 1420–1500/1580. Finally, very rapid niveo-aeolian sedimentation prevailed during the period ad 1500/1580–1690. In the same period, some large nival fans accumulated in the Zackenberg lowland as a result of increased niveo-fluvial activity, and niveo-fluvial sediments were also deposited in pre existing fluvial valleys, demonstrating the large areal extension of the nivation activity. The chronology is based on nine AMS ¹⁴C determinations. The intense geomorphological terrestrial activity in northeast Greenland during the LIA is deduced to be primarily due to increased winter wind speeds enabling larger snowpatches to accumulate as a result of increased snowdrifting.
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