The Deglacial to Holocene Paleoceanography of Bering Strait: Results From the SWERUS-C3 Program

TitleThe Deglacial to Holocene Paleoceanography of Bering Strait: Results From the SWERUS-C3 Program
Publication TypeConference Abstract
AuthorsJakobsson, M, Anderson, L, Backman, J, Barrientos, N, Bjork, G, Coxall, H, Cronin, T, de Boer, A, Gemery, L, Jerram, K, Johansson, C, Kirchner, N, Mayer, LA, Mörth, C-M, Nillson, J, Noormets, R, O'Regan, MA, Pearce, C, Semiltov, I, Stranne, C
Conference Name2017 Fall Meeting, American Geophysical Union (AGU)
Conference LocationNew Orleans, LA
Conference DatesDecember 11-15

The climate-carbon-cryosphere (C3) interactions in the East Siberian Arctic Ocean and related ocean, river and land areas of the Arctic have been the focus for the SWERUS-C3 Program (Swedish – Russian – US Arctic Ocean Investigation of Climate-Cryosphere-Carbon Interactions). This multi-investigator, multi-disciplinary program was carried out on a two-leg 90-day long expedition in 2014 with Swedish icebreaker Oden. One component of the expedition consisted of geophysical mapping and coring of Herald Canyon, located on the Chukchi Sea shelf north of the Bering Strait in the western Arctic Ocean. Herald Canyon is strategically placed to capture the history of the Pacific-Arctic Ocean connection and related changes in Arctic Ocean paleoceanography. Here we present a summary of key results from analyses of the marine geophysical mapping data and cores collected from Herald Canyon on the shelf and slope that proved to be particularly well suited for paleoceanographic reconstruction. For example, we provide a new age constraint of 11 cal ka BP on sediments from the uppermost slope for the initial flooding of the Bering Land Bridge and reestablishment of the Pacific-Arctic Ocean connection following the last glaciation. This age corresponds to meltwater pulse 1b (MWP1b) known as a post-Younger Dryas warming in many sea level and paleoclimate records. In addition, high late Holocene sedimentation rates that range between about 100 and 300 cm kyr-1, in Herald Canyon permitted paleoceanographic reconstructions of ocean circulation and sea ice cover at centennial scales throughout the late Holocene. Evidence suggests varying influence from inflowing Pacific water into the western Arctic Ocean including some evidence for quasi-cyclic variability in several paleoceanographic parameters, e.g. micropaleontological assemblages, isotope geochemistry and sediment physical properties.