Biogeochemistry of the Eastern Weddell Gyre

• Main Authors: Geibert, Walter, Assmy, Philipp, Bakker, Dorothee C E, Hanfland, Claudia, Hoppema, Mario, Pichevin, Laetitia, Schröder, Michael, Schwarz, Jill Nicola, Stimac, Ingrid, Usbeck, Regina, Webb, Adrian
• Format: Other/Unknown Material
• Language: English
• Published: PANGAEA 2010
• Subjects: ANT-XX/2; AWI_MarGeoChem; CTD/Rosette; CTD-RO; Indian Ocean; Lazarev Sea; Marine Geochemistry @ AWI; MIC; MiniCorer; MUC; MULT; MultiCorer; Multiple investigations; Polarstern; Priority Programme 1158 Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; PS63/021-1; PS63/022-2; PS63/023-1; PS63/024-1; PS63/025-1; PS63/026-2; PS63/027-1; PS63/028-1; PS63/029-1; PS63/030-5; PS63/031-1; PS63/032-1; PS63/033-4; PS63/034-1; PS63/035-1; PS63/036-2; PS63/037-3; PS63/038-3; PS63/039-1; PS63/040-1; PS63/041-3; PS63/042-3; PS63/043-1; PS63/044-1; PS63/046-1; PS63/047-1; PS63/048-1; PS63/049-1; PS63/050-1; PS63/052-1; PS63/053-1; PS63/054-4; PS63/054-5; PS63/055-3; PS63/056-1; Antarc*; Antarctic; Iceberg*; Phytoplankton; Sea ice; Southern Ocean
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.726958; https://doi.org/10.1594/PANGAEA.726958

The Southern Ocean (SO) plays a key role in modulating atmospheric CO2 via physical and biological processes. However, over much of the SO, biological activity is iron-limited. New in situ data from the Antarctic zone south of Africa in a region centered at -20°E - 25°E reveal a previously overlooked region of high primary production, comparable in size to the northwest African upwelling region. Here, sea ice together with enclosed icebergs is channeled by prevailing winds to the eastern boundary of the Weddell Gyre, where a sharp transition to warmer waters causes melting. This cumulative melting provides a steady source of iron, fuelling an intense phytoplankton bloom that is not fully captured by monthly satellite production estimates. These findings imply that future changes in sea-ice cover and dynamics could have a significant effect on carbon sequestration in the SO.