Publication Date:
2019-07-16
Description:
In order to study the modern sea surface characteristics of the sub-polar North Pacific and the Bering Sea,
i.e. sea surface temperature (SST) and sea ice cover, surface sediments recovered during the RV Sonne
Expedition 202 in 2009 were analysed. To distinguish between marine and terrestrial organic carbon,
hydrogen index values, long chain n-alkanes and specific sterols have been determined. The results show
that in the Bering Sea, especially on the sea slope, the organic carbon source is mainly caused by high
primary production. In the North Pacific, on the other hand, the organic material originates predominantly
from terrestrial higher plants, probably related to dust input from Asia. SST has been reconstructed
using the modified alkenone unsaturation index. Calibration from Müller et al. (1998) offers the most
reliable estimate of mean annual temperature in the central North Pacific but does not correlate with
mean annual temperature throughout the study area. In the eastern North Pacific and the Bering Sea,
the Sikes et al. (1997) calibration seems to be more accurate and matches summer SST. The distribution
of the novel sea ice proxy IP25 (highly branched C25 isoprenoid alkene) in surface sediments is in accord
with the modern spring sea ice edge and shows the potential of this proxy to track past variation in sea
ice cover in the study area.
Repository Name:
EPIC Alfred Wegener Institut
Type:
Article
,
isiRev
Format:
application/pdf
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