Canadian Arctic Archipelago shelf-ocean interactions: a major iron source to Pacific derived waters transiting to the Atlantic

• Published in: Global Biogeochemical Cycles
• Main Authors: Colombo, Manuel, Rogalla, Birgit, Li, Jingxuan, Allen, Susan E., Orians, Kristin J., Maldonado, Maria T.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: American Geophysical Union 2021
• Subjects: Iron distributions; Sediment resuspension; Iron export; Trace metal biogeochemistry; Canadian Arctic Ocean; GEOTRACES; Arctic; Arctic Ocean; Baffin Bay; Canada; Canadian Arctic Archipelago; Jones Sound; Lancaster Sound; Nares; Pacific; Arctic Archipelago; Baffin; canada basin; Nares strait; North Atlantic
• Online Access: https://hdl.handle.net/1912/27954

Author Posting. © American Geophysical Union, 2021. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Global Biogeochemical Cycles 35(10), (2021): e2021GB007058, https://doi.org/10.1029/2021GB007058. Continental shelves are important sources of iron (Fe) in the land-dominated Arctic Ocean. To understand the export of Fe from the Arctic to Baffin Bay (BB) and the North Atlantic, we studied the alteration of the Fe signature in waters transiting the Canadian Arctic Archipelago (CAA). During its transit through the CAA, inflowing Arctic Waters from the Canada Basin become enriched in Fe as result of strong sediment resuspension and enhanced sediment-water interactions (non-reductive dissolution). These high Fe waters are exported to BB, where approximately 10.7 kt of Fe are delivered yearly from Lancaster Sound. Furthermore, if the two remaining main CAA pathways (Jones Sound and Nares Strait) are included, this shelf environment would be a dominant source term of Fe (dFe + pFe: 26–90 kt y−1) to Baffin Bay. The conservative Fe flux estimate (26 kt y−1) is 1.7–38 times greater than atmospheric inputs, and may be crucial in supporting primary production and nitrogen fixation in BB and beyond. This work was supported by the Natural Sciences and Engineering Research Council of Canada (Grant NSERC-CCAR), the Northern Scientific Training Program, and by the University of British Columbia through a Four Year Fellowship to B. Rogalla. 2022-03-20