Articles | Volume 22, issue 4
https://doi.org/10.5194/os-22-2621-2026
© 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/os-22-2621-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
28 Aug 2026
Research article |
| 28 Aug 2026
| 28 Aug 2026
Krill defecation at depth reduces carbon flux attenuation in the Weddell Sea euphotic zone
Florence Atherden
CORRESPONDING AUTHOR
British Antarctic Survey, Cambridge, UK
Emily Rowlands
British Antarctic Survey, Cambridge, UK
Gareth Flint
British Antarctic Survey, Cambridge, UK
Sophie Fielding
British Antarctic Survey, Cambridge, UK
Katrin Schmidt
University of Plymouth, Plymouth, UK
Elaine Fileman
Plymouth Marine Laboratory, Plymouth, UK
Maren Richter
University of East Anglia, Norwich, UK
Bethany Wilkinson
Plymouth Marine Laboratory, Plymouth, UK
Angus Atkinson
Plymouth Marine Laboratory, Plymouth, UK
Clara Manno
CORRESPONDING AUTHOR
British Antarctic Survey, Cambridge, UK
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Short summary
The Southern Ocean influences global climate, in part, through biological production of carbon-rich particles which trap atmospheric CO2 in the deep ocean. Our study highlights that krill defecating at 50–100 m and injecting carbon-rich pellets effectively counteracts the "typical" scenario where the quantity of particles rapidly decreases from the surface, ultimately increasing how much atmospheric carbon is stored. These processes are of global benefit, but vulnerable in a changing climate.
The Southern Ocean influences global climate, in part, through biological production of...
