Year-round marine heat extremes severely impact marine life during the first year at 1.5°C warming
4 affiliations
- 1Marine Science Program, Biological and Environmental Science and Engineering Division (BESE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Kingdom of Saudi Arabia
- 2National Center for Wildlife (NCW), Riyadh 12411, Kingdom of Saudi Arabia
- 3Climate and Environmental Physics, Physics Institute, University of Bern, 3012 Bern, Switzerland
- 4Oeschger Centre for Climate Change Research, University of Bern, 3012 Bern, Switzerland
Abstract
Periods of anomalous ocean heat are becoming more intense and persistent, with consequences for biodiversity, food systems, and coastal resilience. Yet ocean impact assessments often emphasize summer, creating a seasonal bias that can underrepresent the year-round consequences of marine heat extremes. In 2023–2024, ocean surface warming exceeded 1.0°C above pre-industrial levels, coinciding with year-round marine heat extremes across much of the ocean. Here, we provide a rapid global assessment of marine impacts during this exceptional year. We show that summer impacts were frequent and severe, but 29% of non-tropical impacts occurred in cooler seasons. Events involving compound hazards occurred across seasons, though their timing varied by hazard type. Summer assessments alone are therefore insufficient to capture when, where, and how ocean heat threatens marine ecosystems. Rapid, year-round assessments are needed to understand how anomalous heat affects marine ecosystems and dependent societies, while informing preparedness plans for inevitable future extremes.
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BibTeX
@article{klein2026yearround,
title = {{Year-round marine heat extremes severely impact marine life during the first year at 1.5°C warming}},
author = {Shannon Grace Klein and Carlos Angulo‐Preckler and Cassandra Roch and Anieka Janice Parry and Elisa Laiolo and Jacqueline Victoria Alva Garcia and Jordi Solà and Sofia Frappi and Anastasiia Martynova and Eleonora Re and Natalie E. Wildermann and Kah Kheng Lim and Alexandra Steckbauer and Taiba Alamoudi and Chuancheng Fu and Lutfi Afiq‐Rosli and Mai Aldhahri and Amal A. Bajaffer and Héctor Barrios–Garrido and Joanna M. Ogiegło and Naira Pluma and Wajitha J. Raja Mohamed Sait and Diego Elihú Rivera Rosas and Michelle-Nicole Havlik and Thomas Lukas Frölicher and Carlos Manuel Duarte},
journal = {One Earth},
year = {2026},
month = jun,
doi = {10.1016/j.oneear.2026.101746},
url = {https://doi.org/10.1016/j.oneear.2026.101746},
note = {CC BY-NC-ND},
}
RIS
TY - JOUR
TI - Year-round marine heat extremes severely impact marine life during the first year at 1.5°C warming
AU - Shannon Grace Klein
AU - Carlos Angulo‐Preckler
AU - Cassandra Roch
AU - Anieka Janice Parry
AU - Elisa Laiolo
AU - Jacqueline Victoria Alva Garcia
AU - Jordi Solà
AU - Sofia Frappi
AU - Anastasiia Martynova
AU - Eleonora Re
AU - Natalie E. Wildermann
AU - Kah Kheng Lim
AU - Alexandra Steckbauer
AU - Taiba Alamoudi
AU - Chuancheng Fu
AU - Lutfi Afiq‐Rosli
AU - Mai Aldhahri
AU - Amal A. Bajaffer
AU - Héctor Barrios–Garrido
AU - Joanna M. Ogiegło
AU - Naira Pluma
AU - Wajitha J. Raja Mohamed Sait
AU - Diego Elihú Rivera Rosas
AU - Michelle-Nicole Havlik
AU - Thomas Lukas Frölicher
AU - Carlos Manuel Duarte
PY - 2026
DA - 2026/06/23
JO - One Earth
DO - 10.1016/j.oneear.2026.101746
UR - https://doi.org/10.1016/j.oneear.2026.101746
AB - Periods of anomalous ocean heat are becoming more intense and persistent, with consequences for biodiversity, food systems, and coastal resilience. Yet ocean impact assessments often emphasize summer, creating a seasonal bias that can underrepresent the year-round consequences of marine heat extremes. In 2023–2024, ocean surface warming exceeded 1.0°C above pre-industrial levels, coinciding with year-round marine heat extremes across much of the ocean. Here, we provide a rapid global assessment of marine impacts during this exceptional year. We show that summer impacts were frequent and severe, but 29% of non-tropical impacts occurred in cooler seasons. Events involving compound hazards occurred across seasons, though their timing varied by hazard type. Summer assessments alone are therefore insufficient to capture when, where, and how ocean heat threatens marine ecosystems. Rapid, year-round assessments are needed to understand how anomalous heat affects marine ecosystems and dependent societies, while informing preparedness plans for inevitable future extremes.
SN - 2590-3322
SN - 2590-3330
ER -