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Arctic Seminar Series: Arctic sea ice variability

Anne de Vernal from Université du Québec and Velux Professor at the Department of Geoscience visits ARC

2016.03.10 | Susanna Pakkasmaa

Date Mon 30 May
Time 14:00 15:00
Location ARC, Ny Munkegade 114, Building 1540, meeting room 1540-020. Roskilde: i0.19

Natural variability of sea ice cover in the Arctic and subarctic seas documented from sedimentary archives

The reconstruction of sea ice time series beyond instrumental observation is necessary to document the full range of sea ice variations under natural forcing.

Several approaches based on biogenic, geochemical or sedimentological proxies have been developed from marine sediments. Among those, the assemblages of organic-walled dinoflagellate cysts (= dinocysts) permit quantitative estimates of sea ice cover concentration.

Reconstructions from the Canadian Arctic Archipelago illustrate dense sea ice cover throughout the Holocene (last 11 000 years), which contrast with those from the Chukchi and Barents Sea that show large amplitude variations and suggest millennial-scale oscillations with a pacing almost opposite in western vs. eastern Arctic. The overall data available illustrate the natural variability, but also the resilient character of the Arctic sea ice through time.

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Anne de Vernal is acknowledged for her contributions in the field of marine palynology and paleoceanography, and for the development of quantitative approaches for the reconstruction of past sea-surface conditions at high latitudes (temperature, salinity, sea ice). She participated in several expeditions in the North Atlantic and subarctic basins, notably on the Joides Resolution.

Read more about Anne de Vernal's research on ResearchGate.