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A robust, multisite Holocene history of drift ice off northern Iceland: Implications for North Atlantic climate

John T. Andrews·D. Darby·D. Eberle·A. E. Jennings·M. Moros·A. Ogilvie
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Abstract

An important indicator of Holocene climate change is provided by evidence for variations in the extent of drift ice. A proxy for drift ice in Iceland waters is provided by the presence of quartz. Quantitative x-ray diffraction analysis of the < 2 mm sediment fraction was undertaken on 16 cores from around Iceland. The quartz weight (wt.)% estimates from each core were integrated into 250-yr intervals between ????'0.05 and 11.7 cal. ka BP. Median quartz wt.% varied between 0.2 and 3.4 and maximum values ranged between 2.8 and 11.8 wt.%. High values were attained in the early Holocene and minimum values were reached 6 - 7 cal. ka BP. Quartz wt.% then rose steadily during the late Holocene. Our data exhibit no correlation with counts on haematite-stained quartz (HSQ) grains from VM129-191 west of Ireland casting doubt on the ice-transport origin. A pilot study on the provenance of Fe oxide grains in two cores that cover the last 1.3 and 6.1 cal. ka BP indicated a large fraction of the grains between 1 and 6 cal. ka BP were from either Icelandic or presently unsampled sources. However, there was a dramatic increase in Canadian and Russian sources from the Arctic Ocean ???1 cal. ka BP. These data may indicate the beginning of an Arctic Oscillation-like climate mode. ?? 2009 SAGE Publications.

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John T. Andrews, D. Darby, D. Eberle, A. E. Jennings, M. Moros, A. Ogilvie. 2009-02-01. A robust, multisite Holocene history of drift ice off northern Iceland: Implications for North Atlantic climate. https://doi.org/10.1177/0959683608098953

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