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Holocene Environmental Variability
in the Arctic Gateway
Robert F. Spielhagen, Juliane M
ller, Axel Wagner, Kirstin Werner,
Gerrit Lohmann, Matthias Prange and R
ü
diger Stein
ü
Abstract Environmental changes in the region connecting the Arctic Ocean and
the northern North Atlantic were studied for the last 9,000 years (9 ka) by a
combination of proxy-based paleoceanographic reconstructions as well as transient
and time-slice simulations with climate models. Today, the area is perennially ice-
covered in the west and ice-free in the east. Results show that sea-ice conditions
were highly variable on short timescales in the last 9 ka. However, sea-ice proxies
reveal an overall eastward movement of the sea-ice margin,
in line with a
decreasing in
uence of warm Atlantic Water advected to the Arctic Ocean. These
cooling trends were rapidly reversed 100 years ago and replaced by the general
warming in the Arctic. Model results show a consistently high freshwater input to
the Arctic Ocean during the last 7 ka. The signal is robust against the Holocene
cooling trend, however sensitive towards the warming trend of the last century.
These results may play a role in the observed Arctic changes.
Keywords Arctic Ocean
Holocene
Sea ice
Atlantic Water
River run-off
Global warming
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