Articles | Volume 22, issue 3
https://doi.org/10.5194/os-22-1937-2026
© 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-22-1937-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
23 Jun 2026
Research article |
| 23 Jun 2026
| 23 Jun 2026
Investigating the predictability of marine heatwaves at subseasonal to seasonal timescales in New Caledonia, South Pacific
Inès Mangolte
CORRESPONDING AUTHOR
ENTROPIE (Institute of Research for Development (IRD) / University of New Caledonia / University of Reunion / IFREMER), Promenade Roger-Laroque, 98848 Noumea Cedex, New Caledonia, France
EMR9001 SantEco (CNRS / Institute of Research for Development (IRD) / University of New Caledonia / University of Reunion), Promenade Roger-Laroque, 98848 Noumea Cedex, New Caledonia, France
Sophie Cravatte
Institute of Research for Development (IRD) campus, Promenade Roger-Laroque, 98848 Noumea Cedex, New Caledonia, France
LEGOS (Université de Toulouse/CNES/CNRS/IRD), Toulouse, France
Alexandre Ganachaud
Institute of Research for Development (IRD) campus, Promenade Roger-Laroque, 98848 Noumea Cedex, New Caledonia, France
LEGOS (Université de Toulouse/CNES/CNRS/IRD), Toulouse, France
MARBEC (Université Montpellier/CNRS/Ifremer/IRD), Sète, France
Christophe Menkes
ENTROPIE (Institute of Research for Development (IRD) / University of New Caledonia / University of Reunion / IFREMER), Promenade Roger-Laroque, 98848 Noumea Cedex, New Caledonia, France
EMR9001 SantEco (CNRS / Institute of Research for Development (IRD) / University of New Caledonia / University of Reunion), Promenade Roger-Laroque, 98848 Noumea Cedex, New Caledonia, France
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Short summary
Marine heatwaves pose a serious threat to marine ecosystems that will become increasingly important with climate change. Here we show in the Southwest Pacific that dynamical forecasting systems are able to forecast long, large-scale marine heatwaves occurring in austral winter, but have less skill in predicting smaller, shorter events, and summer events. We discuss the implications for operational forecasts dedicated to help marine managers to prepare and mitigate some of their impacts.
Marine heatwaves pose a serious threat to marine ecosystems that will become increasingly...
