Articles | Volume 23, issue 17
https://doi.org/10.5194/bg-23-6229-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-23-6229-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 Sep 2026
Research article |
| 11 Sep 2026
| 11 Sep 2026
Sinking particle fluxes and biological carbon pump efficiency in the Labrador Sea during a Phaeocystis bloom decline
Montserrat Roca-Martí
CORRESPONDING AUTHOR
Department of Oceanography, Dalhousie University, Halifax, NS, Canada
Physics Department, Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Spain
Madeline Healey
Department of Oceanography, Dalhousie University, Halifax, NS, Canada
Colleen E. McBride
Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
Rachel Sipler
Department of Ocean Sciences, Memorial University of Newfoundland, St. John's, NL, Canada
Bigelow Laboratory for Ocean Sciences, East Boothbay, ME, USA
Emmanuel Devred
Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, NS, Canada
Carolina Cisternas-Novoa
Ocean Sciences Centre, Memorial University of Newfoundland, St. John's, NL, Canada
Elisa Romanelli
Institute of Environmental Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, Zurich, Switzerland
Kyoko Ohashi
Department of Oceanography, Dalhousie University, Halifax, NS, Canada
Fisheries and Oceans Canada, Institute of Ocean Sciences, Sidney, BC, Canada
Stephanie S. Kienast
Department of Oceanography, Dalhousie University, Halifax, NS, Canada
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Short summary
We studied a historically large spring phytoplankton bloom in the Labrador Sea to quantify how much carbon reaches the deep ocean. Despite high productivity, only a small fraction of organic carbon sank below the ocean's productive layer, suggesting a limited role of the dominant phytoplankton species (Phaeocystis) in carbon export. Our findings highlight the need for long-term observations to better assess the ocean’s role in carbon sequestration.
We studied a historically large spring phytoplankton bloom in the Labrador Sea to quantify how...
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