East Greenland Ice: Constraining the extent and effects of the Earths largest ice and freshwater pathway

Recent years have seen a decrease in the Arctic sea ice cover, which results from melting as well as export of ice through Fram Strait between Greenland and Svalbard. In order to place the recent changes into a long-term paleo perspective, a comprehensive, targeted study of sea ice and ocean conditions in the East Greenland Current and the marine margins of Greenland during past warm periods is needed, The EastGreen research project is focused on identifying the Holocene (past 12,000 years) variability of the immense belt of sea ice that emanates from the Arctic Ocean through Fram Strait. The research objectives are being explored through a multi-proxy analysis of geographically dispersed paleo records. These are primarily records from marine sediment cores taken from shelves and fjords around Greenland, as well as other paleo evidence that indicates sea ice and glacial conditions around the margins of Greenland. Our analysis of Holocene changes in sea ice along the EGC pathway shows that previous warm periods around 6-8 thousand years ago had greatly reduced sea ice, similar to that expected for future climate change. Our research focused on the past two thousand years suggests an extreme increase of arctic sea ice in the 1300s at the abrupt onset of the Little Ice Age in the 1300s, which coincides with the demise of the Norse colonies in southwest Greenland. Furthermore, the presence of sea ice appears to an effect on marine outlet glaciers from the Greenland ice sheet. Based on marine geological, historical and modern records, we find that not only warm conditions but also cold conditions including more sea ice appear to cause unusual behavior and increased calving from the major glaciers in southeast Greenland.

This research is focused on constraining and understanding the East Greenland Ice, which is the immense belt of sea ice that emanates from the Arctic Ocean through Fram Strait. The motivation for the research are the recent apparent changes in sea ice and terrestrial ice. These findings are based on observations spanning a few decades, such that a long-term paleo perspective is clearly needed. Fragmentary evidence from disparate individual paleo records is suggestive, though there are many uncertainties a nd discrepancies. A comprehensive targeted study of the response of sea ice and ocean conditions in the East Greenland Current and the marine margins of Greenland during Holocene warm periods is clearly warranted. The research objectives issues will be e xplored via a multi-proxy analysis of geographically dispersed paleo records, comprised primarily of existing records from marine cores taken from shelves and fjords around Greenland, as well as other paleo evidence (e.g., lake sediment records, temperatu re history from ice cores and paleo glacial records) indicative of land- and sea-ice conditions around the margins of Greenland. EASTGREEN is an international, multidisciplinary effort that will leverage a number of recently developed new paleo records.