Articles | Volume 22, issue 2
https://doi.org/10.5194/os-22-1329-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/os-22-1329-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
27 Apr 2026
Research article |
| 27 Apr 2026
| 27 Apr 2026
Marine heatwaves across the central South Pacific: characteristics, mechanisms, and modulation by El Niño Southern Oscillation
UMR 241 SECOPOL, (IRD, ILM, Ifremer, UPF), Tahiti, French Polynesia
ENTROPIE (IRD, Ifremer, Université de la Réunion, Université de la Nouvelle-Calédonie), Nouméa, New Caledonia
Takeshi Izumo
UMR 241 SECOPOL, (IRD, ILM, Ifremer, UPF), Tahiti, French Polynesia
Alexandre Barboni
Laboratoire d'Etudes en Géophysique et Océanographie Spatiales (LEGOS), Toulouse, France
Carla Chevillard
IFREMER, Tahiti, French Polynesia
Cyril Dutheil
MARBEC, University of Montpellier, CNRS, Ifremer, IRD, Sète, France
Raphaël Legrand
DIRPF, Météo France, Tahiti, French Polynesia
Christophe Menkes
ENTROPIE (IRD, Ifremer, Université de la Réunion, Université de la Nouvelle-Calédonie), Nouméa, New Caledonia
Claire Rocuet
UMR 241 SECOPOL, (IRD, ILM, Ifremer, UPF), Tahiti, French Polynesia
Sophie Cravatte
Université de Toulouse, LEGOS (IRD, CNES, CNRS, UT3), Toulouse, France
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Cited articles
Amaya, D. J., Jacox, M. G., Fewings, M. R., Saba, V. S., Stuecker, M. F., Rykaczewski, R. R., Ross, A. C., Stock, C. A., Capotondi, A., Petrik, C. M., Bograd, S. J., Alexander, M. A., Cheng, W., Hermann, A. J., Kearney, K. A., and Powell, B. S.: Marine heatwaves need clear definitions so coastal communities can adapt, Nature, 616, 29–32, https://doi.org/10.1038/d41586-023-00924-2, 2023.
Andréfouët, S. and Adjeroud, M.: French Polynesia, in: World Seas: an Environmental Evaluation, Elsevier, 827–854, https://doi.org/10.1016/B978-0-08-100853-9.00039-7, 2019.
Andréfouët, S., Dutheil, C., Menkes, C. E., Bador, M., and Lengaigne, M.: Mass mortality events in atoll lagoons: environmental control and increased future vulnerability, Glob. Change Biol., 21, 195–205, https://doi.org/10.1111/gcb.12699, 2015.
Bian, C., Jing, Z., Wang, H., Wu, L., Chen, Z., Gan, B., and Yang, H.: Oceanic mesoscale eddies as crucial drivers of global marine heatwaves, Nat. Commun., 14, 2970, https://doi.org/10.1038/s41467-023-38811-z, 2023.
Bian, C., Jing, Z., Wang, H., and Wu, L.: Scale-Dependent Drivers of Marine Heatwaves Globally, Geophys. Res. Lett., 51, e2023GL107306, https://doi.org/10.1029/2023GL107306, 2024.
Bretherton, C. S., Widmann, M., Dymnikov, V. P., Wallace, J. M., and Bladé, I.: The Effective Number of Spatial Degrees of Freedom of a Time-Varying Field, J. Climate, 12, 1990–2009, https://doi.org/10.1175/1520-0442(1999)012<1990:TENOSD>2.0.CO;2, 1999.
Bruyère, O., Le Gendre, R., Chauveau, M., Bourgeois, B., Varillon, D., Butscher, J., Trophime, T., Follin, Y., Aucan, J., Liao, V., and Andréfouët, S.: Lagoon hydrodynamics of pearl farming atolls: the case of Raroia, Takapoto, Apataki and Takaroa (French Polynesia), Earth Syst. Sci. Data, 15, 5553–5573, https://doi.org/10.5194/essd-15-5553-2023, 2023.
Capotondi, A., Wittenberg, A. T., Kug, J.-S., Takahashi, K., and McPhaden, M. J.: ENSO Diversity, in: El Niño Southern Oscillation in a Changing Climate, American Geophysical Union (AGU), 65–86, https://doi.org/10.1002/9781119548164.ch4, 2020.
Capotondi, A., Rodrigues, R. R., Sen Gupta, A., Benthuysen, J. A., Deser, C., Frölicher, T. L., Lovenduski, N. S., Amaya, D. J., Le Grix, N., Xu, T., Hermes, J., Holbrook, N. J., Martinez-Villalobos, C., Masina, S., Roxy, M. K., Schaeffer, A., Schlegel, R. W., Smith, K. E., and Wang, C.: A global overview of marine heatwaves in a changing climate, Commun. Earth Environ., 5, 701, https://doi.org/10.1038/s43247-024-01806-9, 2024.
Chevillard, C., Le Gendre, R., Menkes, C., Izumo, T., Pagli, B., Van Wynsberge, S., and Cravatte, S.: Sensitivity of marine heatwaves metrics to SST products, focusing on the Tropical Pacific, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2025-5417, 2025.
Cohen, J. T., Thompson, L., Maroon, E., Deppenmeier, A.-L., and Cai, C.: Object-Based Evaluation of Seasonal-to-Multiyear Marine Heatwave Predictions, Geophys. Res. Lett., 52, e2025GL115021, https://doi.org/10.1029/2025GL115021, 2025.
datagouv: Géographie administrative de la Polynésie française, Section Cadastre-Topographie de la Polynésie française, https://www.data.gouv.fr/fr/datasets/geographie-administrative-de-la-polynesie-francaise/ (last access: April 2025).
de Boisséson, E. and Balmaseda, M. A.: Predictability of marine heatwaves: assessment based on the ECMWF seasonal forecast system, Ocean Sci., 20, 265–278, https://doi.org/10.5194/os-20-265-2024, 2024.
DeCarlo, T. M., Gajdzik, L., Ellis, J., Coker, D. J., Roberts, M. B., Hammerman, N. M., Pandolfi, J. M., Monroe, A. A., and Berumen, M. L.: Nutrient-supplying ocean currents modulate coral bleaching susceptibility, Sci. Adv., 6, eabc5493, https://doi.org/10.1126/sciadv.abc5493, 2020.
Dee, D. P., Uppala, S. M., Simmons, A. J., Berrisford, P., Poli, P., Kobayashi, S., Andrae, U., Balmaseda, M. A., Balsamo, G., Bauer, P., Bechtold, P., Beljaars, A. C. M., Van De Berg, L., Bidlot, J., Bormann, N., Delsol, C., Dragani, R., Fuentes, M., Geer, A. J., Haimberger, L., Healy, S. B., Hersbach, H., Hólm, E. V., Isaksen, L., Kållberg, P., Köhler, M., Matricardi, M., McNally, A. P., Monge-Sanz, B. M., Morcrette, J.-J., Park, B. -K., Peubey, C., De Rosnay, P., Tavolato, C., Thépaut, J.-N., and Vitart, F.: The ERA-Interim reanalysis: configuration and performance of the data assimilation system, Q. J. Roy. Meteor. Soc., 137, 553–597, https://doi.org/10.1002/qj.828, 2011.
Deppenmeier, A.-L., Bryan, F. O., Kessler, W. S., and Thompson, L.: Modulation of Cross-Isothermal Velocities with ENSO in the Tropical Pacific Cold Tongue, J. Phys. Oceanogr., 51, 1559–1574, https://doi.org/10.1175/JPO-D-20-0217.1, 2021.
Dutheil, C., Lal, S., Lengaigne, M., Cravatte, S., Menkès, C., Receveur, A., Börgel, F., Gröger, M., Houlbreque, F., Le Gendre, R., Mangolte, I., Peltier, A., and Meier, H. E. M.: The massive 2016 marine heatwave in the Southwest Pacific: An “El Niño–Madden-Julian Oscillation” compound event, Sci. Adv., 10, eadp2948, https://doi.org/10.1126/sciadv.adp2948, 2024.
Elzahaby, Y., Schaeffer, A., Roughan, M., and Delaux, S.: Oceanic Circulation Drives the Deepest and Longest Marine Heatwaves in the East Australian Current System, Geophys. Res. Lett., 48, e2021GL094785, https://doi.org/10.1029/2021GL094785, 2021.
Elzahaby, Y., Schaeffer, A., Roughan, M., and Delaux, S.: Why the Mixed Layer Depth Matters When Diagnosing Marine Heatwave Drivers Using a Heat Budget Approach, Front. Clim., 4, https://doi.org/10.3389/fclim.2022.838017, 2022.
E.U. Copernicus Marine Service Information: Global Ocean Physics Reanalysis, E.U. Copernicus Marine Service Information [data set], https://doi.org/10.48670/moi-00021, 2023.
Glynn, P. W.: Widespread Coral Mortality and the 1982–83 El Niño Warming Event, Environ. Conserv., 11, 133–146, https://doi.org/10.1017/S0376892900013825, 1984.
Gonzalez-Espinosa, P. C. and Donner, S. D.: Cloudiness reduces the bleaching response of coral reefs exposed to heat stress, Glob. Change Biol., 27, 3474–3486, https://doi.org/10.1111/gcb.15676, 2021.
Gregory, C. H., Artana, C., Lama, S., León-FonFay, D., Sala, J., Xiao, F., Xu, T., Capotondi, A., Martinez-Villalobos, C., and Holbrook, N. J.: Global Marine Heatwaves Under Different Flavors of ENSO, Geophys. Res. Lett., 51, e2024GL110399, https://doi.org/10.1029/2024GL110399, 2024.
Gupta, H. and Sil, S.: Assessment of GHRSST and OISST Datasets in Identification of Marine Heat-Waves and Heat-Spikes, IEEE Geosci. Remote S., 21, 1–5, https://doi.org/10.1109/LGRS.2024.3362474, 2024.
Hédouin, L., Rouzé, H., Berthe, C., Perez-Rosales, G., Martinez, E., Chancerelle, Y., Galand, P. E., Lerouvreur, F., Nugues, M. M., Pochon, X., Siu, G., Steneck, R., and Planes, S.: Contrasting patterns of mortality in Polynesian coral reefs following the third global coral bleaching event in 2016, Coral Reefs, 39, 939–952, https://doi.org/10.1007/s00338-020-01914-w, 2020.
Hersbach, H., Bell, B., Berrisford, P., Hirahara, S., Horányi, A., Muñoz-Sabater, J., Nicolas, J., Peubey, C., Radu, R., Schepers, D., Simmons, A., Soci, C., Abdalla, S., Abellan, X., Balsamo, G., Bechtold, P., Biavati, G., Bidlot, J., Bonavita, M., De Chiara, G., Dahlgren, P., Dee, D., Diamantakis, M., Dragani, R., Flemming, J., Forbes, R., Fuentes, M., Geer, A., Haimberger, L., Healy, S., Hogan, R. J., Hólm, E., Janisková, M., Keeley, S., Laloyaux, P., Lopez, P., Lupu, C., Radnoti, G., de Rosnay, P., Rozum, I., Vamborg, F., Villaume, S., and Thépaut, J.-N.: The ERA5 global reanalysis, Q. J. Roy. Meteor. Soc., 146, 1999–2049, https://doi.org/10.1002/qj.3803, 2020.
Hobday, A. J., Alexander, L. V., Perkins, S. E., Smale, D. A., Straub, S. C., Oliver, E. C. J., Benthuysen, J. A., Burrows, M. T., Donat, M. G., Feng, M., Holbrook, N. J., Moore, P. J., Scannell, H. A., Sen Gupta, A., and Wernberg, T.: A hierarchical approach to defining marine heatwaves, Prog. Oceanogr., 141, 227–238, https://doi.org/10.1016/j.pocean.2015.12.014, 2016.
Hobday, A. J., Oliver, E. C. J., Gupta, A. S., Benthuysen, J. A., Burrows, M. T., Donat, M. G., Holbrook, N. J., Moore, P. J., Thomsen, M. S., Wernberg, T., and Smale, D. A.: Categorizing and Naming MARINE HEATWAVES, Oceanography, 31, 162–173, 2018.
Holbrook, N., Sen Gupta, A., Oliver, E., Hobday, A., Benthuysen, J., Scannell, H., Smale, D., and Wernberg, T.: Keeping pace with marine heatwaves, Nat. Rev. Earth Environ., 1, https://doi.org/10.1038/s43017-020-0068-4, 2020.
Holbrook, N. J., Scannell, H. A., Sen Gupta, A., Benthuysen, J. A., Feng, M., Oliver, E. C. J., Alexander, L. V., Burrows, M. T., Donat, M. G., Hobday, A. J., Moore, P. J., Perkins-Kirkpatrick, S. E., Smale, D. A., Straub, S. C., and Wernberg, T.: A global assessment of marine heatwaves and their drivers, Nat. Commun., 10, 2624, https://doi.org/10.1038/s41467-019-10206-z, 2019.
Holbrook, N. J., Hernaman, V., Koshiba, S., Lako, J., Kajtar, J. B., Amosa, P., and Singh, A.: Impacts of marine heatwaves on tropical western and central Pacific Island nations and their communities, Global Planet. Change, 208, 103680, https://doi.org/10.1016/j.gloplacha.2021.103680, 2022.
Huang, B., Liu, C., Banzon, V., Freeman, E., Graham, G., Hankins, B., Smith, T., and Zhang, H.-M.: Improvements of the Daily Optimum Interpolation Sea Surface Temperature (DOISST) Version 2.1, J. Climate, 34, 2923–2939, https://doi.org/10.1175/JCLI-D-20-0166.1, 2021.
Jacox, M. G., Alexander, M. A., Amaya, D., Becker, E., Bograd, S. J., Brodie, S., Hazen, E. L., Pozo Buil, M., and Tommasi, D.: Global seasonal forecasts of marine heatwaves, Nature, 604, 486–490, https://doi.org/10.1038/s41586-022-04573-9, 2022.
Lachs, L., Bythell, J. C., East, H. K., Edwards, A. J., Mumby, P. J., Skirving, W. J., Spady, B. L., and Guest, J. R.: Fine-Tuning Heat Stress Algorithms to Optimise Global Predictions of Mass Coral Bleaching, Remote Sens., 13, 2677, https://doi.org/10.3390/rs13142677, 2021.
Lal, S., Cravatte, S., Menkes, C., Macdonald, J., LeGendre, R., Mangolte, I., Dutheil, C., Holbrook, N., and Nicol, S.: Characterization of Past Marine Heatwaves around South Pacific Island Countries: What really matters?, EGUsphere [preprint], https://doi.org/10.5194/egusphere-2025-3281, 2025.
Le Gendre, R., Varillon, D., Fiat, S., Hocdé, R., de Ramon N'Yeurt, A., Andréfouët, S., Aucan, J., Cravatte, S., Duphil, M., Ganachaud, A., Gaudron, B., Kestenare, E., Liao, V., Pelletier, B., Peltier, A., Schaefer, A.-L., Trophime, T., Van Wynsberge, S., Dandonneau, Y., Allenbach, M., and Menkes, C.: ReefTEMPS: the Pacific Islands coastal temperature network, Earth Syst. Sci. Data, 17, 5277–5301, https://doi.org/10.5194/essd-17-5277-2025, 2025.
Lellouche, J.-M., Greiner, E., Le Galloudec, O., Garric, G., Regnier, C., Drevillon, M., Benkiran, M., Testut, C.-E., Bourdalle-Badie, R., Gasparin, F., Hernandez, O., Levier, B., Drillet, Y., Remy, E., and Le Traon, P.-Y.: Recent updates to the Copernicus Marine Service global ocean monitoring and forecasting real-time
Lellouche, J.-M., Greiner, E., Bourdallé-Badie, R., Garric, G., Melet, A., Drévillon, M., Bricaud, C., Hamon, M., Le Galloudec, O., Regnier, C., Candela, T., Testut, C.-E., Gasparin, F., Ruggiero, G., Benkiran, M., Drillet, Y., Le Traon, P.-Y., Bourdallé-Badie, R., Garric, G., Melet, A., Drévillon, M., Bricaud, C., Hamon, M., Le Galloudec, O., Regnier, C., Candela, T., Testut, C.-E., Gasparin, F., Ruggiero, G., Benkiran, M., Drillet, Y., and Le Traon, P.-Y.: The Copernicus Global
Madec, G., Bell, M., Benshila, R., Blaker, A., Boudrallé-Badie, R., Bricaud, C., Bruciaferri, D., Carneiro, D., Castrillo, M., Calvert, D., Chanut, J., Clementi, E., Coward, A., Lavergne, C. de, Dobricic, S., Epicoco, I., Éthé, C., Fiedler, E., Ford, D., Furner, R., Ganderton, J., Graham, T., Harle, J., Hutchinson, K., Iovino, D., King, R., Lea, D., Levy, C., Lovato, T., Maisonnave, E., Mak, J., Sanchez, J. M. C., Martin, M., Martin, N., Martins, D., Masson, S., Mathiot, P., Mele, F., Mocavero, S., Moulin, A., Müller, S., Nurser, G., Oddo, P., Paronuzzi, S., Paul, J., Peltier, M., Person, R., Rousset, C., Rynders, S., Samson, G., Schroeder, D., Storkey, D., Storto, A., Téchené, S., Vancoppenolle, M., and Wilson, C.: NEMO Ocean Engine Reference Manual, Zenodo, https://doi.org/10.5281/zenodo.1464816, 2024.
Marin, M., Feng, M., Bindoff, N. L., and Phillips, H. E.: Local Drivers of Extreme Upper Ocean Marine Heatwaves Assessed Using a Global Ocean Circulation Model, Front. Clim., 4, https://doi.org/10.3389/fclim.2022.788390, 2022.
Martinez, E., Ganachaud, A., Lefevre, J., and Maamaatuaiahutapu, K.: Central South Pacific thermocline water circulation from a high-resolution ocean model validated against satellite data: Seasonal variability and El Niño 1997–1998 influence, J. Geophys. Res.-Oceans, 114, https://doi.org/10.1029/2008JC004824, 2009.
Moisan, J. R. and Niiler, P. P.: The Seasonal Heat Budget of the North Pacific: Net Heat Flux and Heat Storage Rates (1950–1990), J. Phys. Oceanogr., 28, 401–421, https://doi.org/10.1175/1520-0485(1998)028<0401:TSHBOT>2.0.CO;2, 1998.
Mumby, P., Chisholm, J., Edwards, A., Andrefouet, S., and Jaubert, J.: Cloudy weather may have saved Society Island reef corals during the 1998 ENSO event, Mar. Ecol. Prog. Ser., 222, 209–216, https://doi.org/10.3354/meps222209, 2001a.
Mumby, P., Chisholm, J., Edwards, A., Clark, C., Roark, E., Andrefouet, S., and Jaubert, J.: Unprecedented bleaching-induced mortality in Porites spp. at Rangiroa Atoll, French Polynesia, Mar. Biol., 139, 183–189, https://doi.org/10.1007/s002270100575, 2001b.
Oliver, E. C. J., Donat, M. G., Burrows, M. T., Moore, P. J., Smale, D. A., Alexander, L. V., Benthuysen, J. A., Feng, M., Sen Gupta, A., Hobday, A. J., Holbrook, N. J., Perkins-Kirkpatrick, S. E., Scannell, H. A., Straub, S. C., and Wernberg, T.: Longer and more frequent marine heatwaves over the past century, Nat. Commun., 9, 1324, https://doi.org/10.1038/s41467-018-03732-9, 2018.
Oliver, E. C. J., Burrows, M. T., Donat, M. G., Sen Gupta, A., Alexander, L. V., Perkins-Kirkpatrick, S. E., Benthuysen, J. A., Hobday, A. J., Holbrook, N. J., Moore, P. J., Thomsen, M. S., Wernberg, T., and Smale, D. A.: Projected Marine Heatwaves in the 21st Century and the Potential for Ecological Impact, Front. Mar. Sci., 6, 734, https://doi.org/10.3389/fmars.2019.00734, 2019.
Oliver, E. C. J., Benthuysen, J. A., Darmaraki, S., Donat, M. G., Hobday, A. J., Holbrook, N. J., Schlegel, R. W., and Gupta, A. S.: Marine Heatwaves, Annu. Rev. Mar. Sci., 13, 313–342, https://doi.org/10.1146/annurev-marine-032720-095144, 2021.
Pagli, B., Izumo, T., Cravatte, S. E., Hopuare, M., Martinoni-Lapierre, S., Laurent, V., Menkes, C., Monselesan, D., and Auffray, S.: The Diverse Impacts of El Niño and La Niña Events over the South Pacific and in French Polynesia, J. Climate, 38, 2681–2701, https://doi.org/10.1175/JCLI-D-24-0408.1, 2025.
Paulson, C. A. and Simpson, J. J.: Irradiance Measurements in the Upper Ocean, J. Phys. Oceanogr., 7, 952–956, https://doi.org/10.1175/1520-0485(1977)007<0952:IMITUO>2.0.CO;2, 1977.
Petrelli, P.: Improved threshold and documents, GitHub [code], https://github.com/coecms/xmhw/releases/tag/0.7.0 (last access: June 2025), 2021.
Pilo, G. S., Holbrook, N. J., Kiss, A. E., and Hogg, A. McC.: Sensitivity of Marine Heatwave Metrics to Ocean Model Resolution, Geophys. Res. Lett., 46, 14604–14612, https://doi.org/10.1029/2019GL084928, 2019.
Schlegel, R. W., Oliver, E. C. J., and Chen, K.: Drivers of Marine Heatwaves in the Northwest Atlantic: The Role of Air–Sea Interaction During Onset and Decline, Front. Mar. Sci., 8, https://doi.org/10.3389/fmars.2021.627970, 2021.
Sen Gupta, A.: Marine heatwaves: definition duel heats up, Nature, 617, 465–465, https://doi.org/10.1038/d41586-023-01619-4, 2023.
Sen Gupta, A., Thomsen, M., Benthuysen, J. A., Hobday, A. J., Oliver, E., Alexander, L. V., Burrows, M. T., Donat, M. G., Feng, M., Holbrook, N. J., Perkins-Kirkpatrick, S., Moore, P. J., Rodrigues, R. R., Scannell, H. A., Taschetto, A. S., Ummenhofer, C. C., Wernberg, T., and Smale, D. A.: Drivers and impacts of the most extreme marine heatwave events, Sci. Rep., 10, 19359, https://doi.org/10.1038/s41598-020-75445-3, 2020.
Skirving, W., Marsh, B., De La Cour, J., Liu, G., Harris, A., Maturi, E., Geiger, E., and Eakin, C. M.: CoralTemp and the Coral Reef Watch Coral Bleaching Heat Stress Product Suite Version 3.1, Remote Sens., 12, 3856, https://doi.org/10.3390/rs12233856, 2020.
Smith, K. E., Sen Gupta, A., Amaya, D., Benthuysen, J. A., Burrows, M. T., Capotondi, A., Filbee-Dexter, K., Frölicher, T. L., Hobday, A. J., Holbrook, N. J., Malan, N., Moore, P. J., Oliver, E. C. J., Richaud, B., Salcedo-Castro, J., Smale, D. A., Thomsen, M., and Wernberg, T.: Baseline matters: Challenges and implications of different marine heatwave baselines, Prog. Oceanogr., 231, 103404, https://doi.org/10.1016/j.pocean.2024.103404, 2025.
Stackhouse, P. W., Cox, S. J., Mikovitz, J. C., and Zhang, T.: GEWEX (Global Energy and Water Exchanges Project): Surface Radiation Budget (SRB) Release 4 Integrated Product (IP4) – Algorithm Theoretical Basis Document and Evaluation, NASA, 2021.
Van Wynsberge, S., Menkes, C., Le Gendre, R., Passfield, T., and Andréfouët, S.: Are Sea Surface Temperature satellite measurements reliable proxies of lagoon temperature in the South Pacific?, Estuar. Coast. Shelf S., 199, 117–124, https://doi.org/10.1016/j.ecss.2017.09.033, 2017.
Van Wynsberge, S., Quéré, R., Andréfouët, S., Autret, E., and Le Gendre, R.: Spatial variability of temperature inside atoll lagoons assessed with Landsat-8 satellite imagery, Remote Sens. Appl. Soc. Environ., 36, 101340, https://doi.org/10.1016/j.rsase.2024.101340, 2024.
Vincent, E. M., Lengaigne, M., Menkes, C. E., Jourdain, N. C., Marchesiello, P., and Madec, G.: Interannual variability of the South Pacific Convergence Zone and implications for tropical cyclone genesis, Clim. Dynam., 36, 1881–1896, https://doi.org/10.1007/s00382-009-0716-3, 2011.
Vogt, L., Burger, F. A., Griffies, S. M., and Frölicher, T. L.: Local Drivers of Marine Heatwaves: A Global Analysis With an Earth System Model, Front. Clim., 4, https://doi.org/10.3389/fclim.2022.847995, 2022.
Watanabe, M., Kang, S. M., Collins, M., Hwang, Y.-T., McGregor, S., and Stuecker, M. F.: Possible shift in controls of the tropical Pacific surface warming pattern, Nature, 630, 315–324, https://doi.org/10.1038/s41586-024-07452-7, 2024.
Whitaker, H. and DeCarlo, T.: Re(de)fining degree-heating week: coral bleaching variability necessitates regional and temporal optimization of global forecast model stress metrics, Coral Reefs, 43, 969–984, https://doi.org/10.1007/s00338-024-02512-w, 2024.
Wyatt, A. S. J., Leichter, J. J., Washburn, L., Kui, L., Edmunds, P. J., and Burgess, S. C.: Hidden heatwaves and severe coral bleaching linked to mesoscale eddies and thermocline dynamics, Nat. Commun., 14, 25, https://doi.org/10.1038/s41467-022-35550-5, 2023.
Zaron, E. D.: Baroclinic Tidal Sea Level from Exact-Repeat Mission Altimetry, J. Phys. Oceanogr., 49, 193–210, https://doi.org/10.1175/JPO-D-18-0127.1, 2019.
Zhang, Y., Du, Y., Feng, M., and Hobday, A. J.: Vertical structures of marine heatwaves, Nat. Commun., 14, 1–12, https://doi.org/10.1038/s41467-023-42219-0, 2023.
Short summary
Marine heatwaves—periods of unusually warm ocean temperatures—are becoming more frequent and intense with climate change. These events can harm marine ecosystems, especially in vulnerable regions like French Polynesia. Here, we used satellite sea surface temperature data and ocean reanalysis to characterize past events. We investigated their characteristics, variability linked to El Niño Southern Oscillation, and the physical mechanisms driving their onset and decay across the region.
Marine heatwaves—periods of unusually warm ocean temperatures—are becoming more frequent and...
