A robust, multisite Holocene history of drift ice off northern Iceland: implications for North Atlantic climate
|Author(s)||Andrews John T.1, 2, Darby Dennis3, Eberle Dennis4, Jennings Anne E.1, 2, Moros Matthias5, 6, Ogilvie Astrid1, 7|
|Affiliation(s)||1 : INSTAAR, Boulder, CO 80303 USA.
2 : Univ Colorado, Dept Geol Sci, Boulder, CO 80303 USA.
3 : Old Dominion Univ, Dept Ocean Earth & Atmospher Sci, Norfolk, VA 23529 USA.
4 : US Geol Survey, Boulder, CO 80303 USA.
5 : Bjerknes Ctr Climate Res, N-5007 Bergen, Norway.
6 : Balt Sea Res Inst, D-18119 Rostock, Germany.
7 : Univ Colorado, Dept Anthropol, Boulder, CO 80303 USA.
|Source||Holocene (0959-6836) (Sage Publications Ltd), 2009-02 , Vol. 19 , N. 1 , P. 71-77|
|WOS© Times Cited||49|
|Keyword(s)||Ice rafted debris, Iceland, quartz, drift ice, Holocene, Arctic basin|
|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 I 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 similar to 1 cal. ka BP. These data may indicate the beginning of an Arctic Oscillation-like climate mode.|