Articles | Volume 22, issue 16
https://doi.org/10.5194/bg-22-4261-2025
© Author(s) 2025. 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-22-4261-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
28 Aug 2025
Research article |
| 28 Aug 2025
| 28 Aug 2025
Evolution of biogeochemical properties inside poleward undercurrent eddies in the southeast Pacific Ocean
Lenna Ortiz-Castillo
CORRESPONDING AUTHOR
Centro de Investigación en Ecosistemas de la Patagonia (CIEP), Coyhaique, Chile
Programa de Postgrado en Oceanografía, Departamento de Oceanografía, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción, Chile
Millennium Institute of Oceanography, Universidad de Concepción, Concepción, Chile
Millennium Institute of Oceanography, Universidad de Concepción, Concepción, Chile
Department of Geophysics, University of Concepcion, Concepción, Chile
Centro de Instrumentación Oceanográfica, Universidad de Concepción, Concepción, Chile
Marcela Cornejo-D'Ottone
Escuela de Ciencias del Mar and Núcleo Milenio para el estudio de la Desoxigenación del Océano Pacífico Sur oriental (DEOXS), Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
Boris Dewitte
Centro de Estudios Avanzados en Zonas Áridas (CEAZA), Coquimbo, Chile
Departamento de Biología Marina, Facultad de Ciencias del Mar, Universidad Católica del Norte, Coquimbo, Chile
CECI, Université de Toulouse III, CERFACS/CNRS, Toulouse, France
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Manuel Torres-Godoy, Oscar Pizarro, Boris Dewitte, and Vera Oerder
EGUsphere, https://doi.org/10.5194/egusphere-2025-1311, https://doi.org/10.5194/egusphere-2025-1311, 2025
Short summary
Short summary
The Southeast Pacific plays a key role in transporting deep ocean water toward the Southern Ocean through a deep southward flow along the Chilean coast. This study explores its variations and links to El Niño–Southern Oscillation. We found that the deep flow strengthens during El Niño and weakens during La Niña. These changes are tied to large-scale ocean shifts and energy transfers from surface to deep waters. Smaller-scale ocean processes also influence the flow, especially near the coast.
Macarena Díaz-Astudillo, Manuel Castillo, Pedro A. Figueroa, Leonardo R. Castro, Ramiro Riquelme-Bugueño, Iván Pérez-Santos, Oscar Pizarro, and Gonzalo S. Saldías
EGUsphere, https://doi.org/10.5194/egusphere-2025-417, https://doi.org/10.5194/egusphere-2025-417, 2025
Short summary
Short summary
Submarine canyons are known hotspots of marine productivity and biodiversity, but we don’t fully understand why. We studied a submarine canyon located in central Chile and found that it’s a highly dynamic environment in both space and time. We think that the alternating currents and the contrasting distribution of zooplankton within the canyon might interact to promote zooplankton retention. Our results help to explain why submarine canyons host such high zooplankton diversity and abundance.
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Short summary
Poleward undercurrent eddies (Puddies) transport the source water mass with low oxygen hundreds of kilometers away from the coast. A simulation based on a physical–biogeochemical model was used to characterize the average biogeochemical conditions inside the Puddies during their lifetime while modifying the conditions in the open sea. Our findings show that the biological activity extends the low-oxygen core conditions counteracted by advection processes that tend to ventilate the core.
Poleward undercurrent eddies (Puddies) transport the source water mass with low oxygen hundreds...
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