Publication Date:
2022-05-25
Description:
Author Posting. © The Author(s), 2011. This is the author's version of the work. It is posted here by permission of Nature Publishing Group for personal use, not for redistribution. The definitive version was published in Nature Geoscience 5 (2012): 37-41, doi:10.1038/ngeo1349.
Description:
During the early 2000s the Greenland Ice Sheet experienced the largest ice mass loss observed
on the instrumental record1, largely as a result of the acceleration, thinning and retreat of
major outlet glaciers in West and Southeast Greenland2-5. The quasi-simultaneous change in the glaciers suggests a common climate forcing and increasing air6 and ocean7-8 temperatures
have been indicated as potential triggers. Here, we present a new record of calving activity of
Helheim Glacier, East Greenland, extending back to c. 1890 AD. This record was obtained by
analysing sedimentary deposits from Sermilik Fjord, where Helheim Glacier terminates, and
uses the annual deposition of sand grains as a proxy for iceberg discharge. The 120 year long
record reveals large fluctuations in calving rates, but that the present high rate was
reproduced only in the 1930s. A comparison with climate indices indicates that high calving
activity coincides with increased Atlantic Water and decreased Polar Water influence on the
shelf, warm summers and a negative phase of the North Atlantic Oscillation. Our analysis
provides evidence that Helheim Glacier responds to short-term (3-10 years) large-scale
oceanic and atmospheric fluctuations.
Description:
This study has been supported by Geocenter Denmark in financial support to the SEDIMICE
project. CSA was supported by the Danish Council for Independent Research│Nature and Universe
(Grant no. 09-064954/FNU). FSt was supported by NSF ARC 0909373 and by WHOI’s Ocean and
Climate Change Institute and MHRI was supported by the Danish Agency for Science, Technology
and Innovation.
Description:
2012-06-11
Repository Name:
Woods Hole Open Access Server
Type:
Preprint
Format:
application/pdf
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