Articles | Volume 22, issue 2
https://doi.org/10.5194/os-22-961-2026
© 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-22-961-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Marine heatwaves variability and trends in the Patagonian Shelf
Ana L. Delgado
CORRESPONDING AUTHOR
Institut Mediterrani d'Estudis Avançats (IMEDEA, CSIC-UIB), 07190 Esporles, Spain
Instituto Argentino de Oceanografía (IADO-CONICET-UNS), 8000 Bahía Blanca, Argentina
Vincent Combes
CORRESPONDING AUTHOR
Institut Mediterrani d'Estudis Avançats (IMEDEA, CSIC-UIB), 07190 Esporles, Spain
Departamento de Física, Universitat de les Illes Balears, 07122 Palma de Mallorca, Spain
Gotzon Basterretxea
Institut Mediterrani d'Estudis Avançats (IMEDEA, CSIC-UIB), 07190 Esporles, Spain
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Paul Hargous, Vincent Combes, Bàrbara Barceló-Llull, and Ananda Pascual
Ocean Sci., 22, 549–564, https://doi.org/10.5194/os-22-549-2026, https://doi.org/10.5194/os-22-549-2026, 2026
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Over the last three decades, satellites have revealed rising activity of swirling ocean currents in the Mediterranean Sea. We show that the strength of this increase depends strongly on how satellite data are combined. Products that merge many satellites may give the impression of stronger changes simply because coverage improved over time. This work underlines the importance of using stable and consistent data sets to track long-term changes in ocean variability.
Alexander Hayward, Nishka Dasgupta, Ronan McAdam, Mark R. Payne, Roshin P. Raj, Giulia Bonino, Sourav Chatterjee, Vincent Combes, Dimitra Denaxa, Francesco De Rovere, Pia Englyst, Veera Haapaniemi, Paul Hargous, Jacob Høyer, K. Ajith Joseph, Beatriz Lopes, Ana Oliveira, João Paixão, Fabiola Silva, Saradhy Surendran, Artemis Zegna-Rata, and Steffen Olsen
Earth Syst. Sci. Data Discuss., https://doi.org/10.5194/essd-2025-590, https://doi.org/10.5194/essd-2025-590, 2025
Preprint under review for ESSD
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We present a global marine heatwave dataset (1982–2024) based on satellite sea surface temperature. The dataset applies multiple definitions in parallel, varying baselines, thresholds, detrending, and event durations. It enables consistent comparisons of marine heatwave characterisation across methods and supports climate monitoring, model evaluation, and ecological impact studies.
Marine Di Stefano, David Nerini, Itziar Alvarez, Giandomenico Ardizzone, Patrick Astruch, Gotzon Basterretxea, Aurélie Blanfuné, Denis Bonhomme, Antonio Calò, Ignacio Catalan, Carlo Cattano, Adrien Cheminée, Romain Crec'hriou, Amalia Cuadros, Antonio Di Franco, Carlos Diaz-Gil, Tristan Estaque, Robin Faillettaz, Fabiana C. Félix-Hackradt, José Antonio Garcia-Charton, Paolo Guidetti, Loïc Guilloux, Jean-Georges Harmelin, Mireille Harmelin-Vivien, Manuel Hidalgo, Hilmar Hinz, Jean-Olivier Irisson, Gabriele La Mesa, Laurence Le Diréach, Philippe Lenfant, Enrique Macpherson, Sanja Matić-Skoko, Manon Mercader, Marco Milazzo, Tiffany Monfort, Joan Moranta, Manuel Muntoni, Matteo Murenu, Lucie Nunez, M. Pilar Olivar, Jérémy Pastor, Ángel Pérez-Ruzafa, Serge Planes, Nuria Raventos, Justine Richaume, Elodie Rouanet, Erwan Roussel, Sandrine Ruitton, Ana Sabatés, Thierry Thibaut, Daniele Ventura, Laurent Vigliola, Dario Vrdoljak, and Vincent Rossi
Earth Syst. Sci. Data, 16, 3851–3871, https://doi.org/10.5194/essd-16-3851-2024, https://doi.org/10.5194/essd-16-3851-2024, 2024
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We build a compilation of early-life dispersal traits for coastal fish species. The database contains over 110 000 entries collected from 1993 to 2021 in the western Mediterranean. All observations are harmonized to provide information on dates and locations of spawning and settlement, along with pelagic larval durations. When applicable, missing data are reconstructed from dynamic energy budget theory. Statistical analyses reveal sampling biases across taxa, space and time.
Gotzon Basterretxea, Joan S. Font-Muñoz, Ismael Hernández-Carrasco, and Sergio A. Sañudo-Wilhelmy
Ocean Sci., 19, 973–990, https://doi.org/10.5194/os-19-973-2023, https://doi.org/10.5194/os-19-973-2023, 2023
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We examine global ocean color data and modeling outputs of nutrients using SOM analysis to identify characteristic spatial and temporal patterns of HNLC regions and their association with different climate modes. HNLC regions in polar and subpolar areas have experienced an increase in phytoplankton biomass over the last decades, particularly in the Southern Ocean. Our study finds that chlorophyll variations in HNLC regions respond to major climate variability signals.
Paula Maria Salgado-Hernanz, Aurore Regaudie-de-Gioux, David Antoine, and Gotzon Basterretxea
Biogeosciences, 19, 47–69, https://doi.org/10.5194/bg-19-47-2022, https://doi.org/10.5194/bg-19-47-2022, 2022
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For the first time, this study presents the characteristics of primary production in coastal regions of the Mediterranean Sea based on satellite-borne observations for the period 2002–2016. The study concludes that there are significant spatial and temporal variations among different regions. Quantifying primary production is of special importance in the marine food web and in the sequestration of carbon dioxide from the atmosphere to the deep waters.
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Short summary
Marine heatwaves are becoming more common and can disrupt life in the sea, yet little was known about them on the Patagonian Shelf, one of the world's most productive marine regions. We found they occur about twice a year and are increasing in the north as the ocean warms. Climate variability such as La Niña can intensify them, highlighting growing risks for marine ecosystems.
Marine heatwaves are becoming more common and can disrupt life in the sea, yet little was known...