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1. Removal of Refractory Dissolved Organic Carbon in the Amundsen Sea, Antarctica

   https://doi.org/10.1038/s41598-020-57870-6  

   Fang, Ling; Lee, SangHoon; Lee, Shin-Ah; Hahm, Doshik; Kim, Guebuem; Druffel, Ellen R.; Hwang, Jeomshik (December 2020, Scientific Reports)

   null (Ed.)

   Abstract The removal mechanism of refractory deep-ocean dissolved organic carbon (deep-DOC) is poorly understood. The Amundsen Sea Polynya (ASP) serves as a natural test basin for assessing the fate of deep-DOC when it is supplied with a large amount of fresh-DOC and exposed to strong solar radiation during the polynya opening in austral summer. We measured the radiocarbon content of DOC in the water column on the western Amundsen shelf. The radiocarbon content of DOC in the surface water of the ASP reflected higher primary production than in the region covered by sea ice. The radiocarbon measurements of DOC, taken two years apart in the ASP, were different, suggesting rapid cycling of DOC. The increase in DOC concentration was less than expected from the observed increase in radiocarbon content from those at the greatest depths. Based on a radiocarbon mass balance, we show that deep-DOC is consumed along with fresh-DOC in the ASP. Our observations imply that water circulation through the surface layer, where fresh-DOC is produced, may play an important role in global DOC cycling. 

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2. Pathways of Inter‐Basin Exchange From the Bellingshausen Sea to the Amundsen Sea

   https://doi.org/10.1029/2023JC020080  

   Flexas, M_Mar; Thompson, Andrew_F; Robertson, Megan_L; Speer, Kevin; Sheehan, Peter_M_F; Heywood, Karen_J (June 2024, Journal of Geophysical Research: Oceans)

   Abstract The West Antarctic Ice Sheet is experiencing rapid thinning of its floating ice shelves, largely attributed to oceanic basal melt. Numerical models suggest that the Bellingshausen Sea has a key role in setting water properties in the Amundsen Sea and further downstream. Yet, observations confirming these pathways of volume and tracer exchange between coast and shelf break and their impact on inter‐sea exchange remain sparse. Here we analyze the circulation and distribution of glacial meltwater at the boundary between the Bellingshausen Sea and the Amundsen Sea using a combination of glider observations from January 2020 and hydrographic data from instrumented seals. Meltwater distributions over previously unmapped western regions of the continental shelf and slope reveal two distinct meltwater cores with different optical backscatter properties. At Belgica Trough, a subsurface meltwater peak is linked with hydrographic properties from Venable Ice Shelf. West of Belgica Trough, the vertical structure of meltwater concentration changes, with peak values occurring at greater depths and denser isopycnals. Hydrographic analysis suggests that the western (deep) meltwater core is supplied from the eastern part of Abbot Ice Shelf, and is exported to the shelf break via a previously‐overlooked bathymetric trough (here named Seal Trough). Hydrographic sections constructed from seal data reveal that the Antarctic Coastal Current extends west past Belgica Trough, delivering meltwater to the Amundsen Sea. Each of these circulation elements has distinct dynamical implications for the evolution of ice shelves and water masses both locally and downstream, in the Amundsen Sea and beyond. 

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3. Volcanogenic fluxes of iron from the seafloor in the Amundsen Sea, West Antarctica

   https://doi.org/10.1016/j.marchem.2023.104250  

   Herbert, Lisa C.; Lepp, Allison P.; Garcia, Santiago Munevar; Browning, Arianne; Miller, Lauren E.; Wellner, Julia; Severmann, Silke; Hillenbrand, Claus-Dieter; Johnson, Joanne S.; Sherrell, Robert M. (June 2023, Marine Chemistry)
4. An Investigation of Gas Exchange and Water Circulation in the Amundsen Sea Based On Dissolved Inorganic Radiocarbon

   https://doi.org/10.1029/2018GL079464  

   Kim, Bumsoo; Lee, SangHoon; Kim, Minkyoung; Hahm, Doshik; Rhee, Tae Siek; Hwang, Jeomshik (November 2018, Geophysical Research Letters)
5. The role of the Dotson Ice Shelf and Circumpolar Deep Water as driver and source of dissolved and particulate iron and manganese in the Amundsen Sea polynya, Southern Ocean

   https://doi.org/10.1016/j.marchem.2022.104161  

   van Manen, Mathijs; Aoki, Shigeru; Brussaard, Corina P.D.; Conway, Tim M.; Eich, Charlotte; Gerringa, Loes J.A.; Jung, Jinyoung; Kim, Tae-Wan; Lee, SangHoon; Lee, Youngju; et al (October 2022, Marine Chemistry)