Liao et al. (2026) Diurnal sea surface temperature amplification enhances surface extremes during marine heatwaves

Identification

• Journal: Communications Earth & Environment
• Year: 2026
• Date: 2026-07-21
• Authors: Enhui Liao, Shiyu Liang, Fengping Wang, Wenchang Yang, Jiaxu Zhang, Wenfang Lu, Young‐Heon Jo, Yan Du, Graeme A. MacGilchrist
• DOI: 10.1038/s43247-026-03841-0

Research Groups

• School of Oceanography, Shanghai Jiao Tong University, Shanghai, China
• John Hopcroft Center for Computer Science, Shanghai Jiao Tong University, Shanghai, China
• Department of Geosciences, Princeton University, Princeton, NJ, USA
• Cooperative Institute for Climate, Ocean, and Ecosystem Studies, University of Washington, Seattle, WA, USA
• NOAA Pacific Marine Environmental Laboratory, Seattle, WA, USA
• School of Marine Sciences, Sun Yat-Sen University, And Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
• Department of Oceanography and Marine Research Institute, Pusan National University, Busan, Republic of Korea.
• State Key Laboratory of Tropical Oceanography, SCSIO, CAS, Guangzhou, China;
• University of Chinese Academy of Sciences, Beijing, China
• School of Earth and Environmental Sciences, University of St Andrews, St Andrews, United Kingdom

Short Summary

This study reveals that diurnal sea surface temperature amplification enhances surface extremes during marine heatwaves. The research shows that the diurnal cycle is systematically amplified under MHW conditions, with enhanced daytime warming and a delayed diurnal phase.

Objective

• Investigate the relationship between diurnal sea surface temperature (SST) amplification and marine heatwaves (MHWs)
• Quantify the effect of diurnal SST amplification on MHW metrics

Study Configuration

• Spatial Scale: Global ocean, with focus on tropical and subtropical regions
• Temporal Scale: Hourly to daily variability within the near-surface ocean during MHW conditions

Methodology and Data

• Models used: MOM6 (global ocean model)
• Data sources: Satellite observations from OSTIA system, MODIS SST, atmospheric reanalysis fields from ERA5

Main Results

• Diurnal cycle is systematically amplified under MHW conditions, with enhanced daytime warming and a delayed diurnal phase
• Global diurnal amplification during MHWs: 19.96±0.36%
• Subskin-based MHW metrics are systematically stronger and exhibit distinct spatial and seasonal patterns

Contributions

• Quantified the effect of diurnal SST amplification on MHW metrics, highlighting its importance for understanding near-surface thermal conditions
• Provided a more representative measure of daytime heatwave intensity experienced by surface-dwelling organisms
• Highlighted the need to incorporate subskin perspectives into ecological risk assessment and operational monitoring frameworks

Funding

• This research was supported by the National Natural Science Foundation of China (Grant No. 41976017)
• The study also received funding from the Shanghai Municipal Education Commission (Grant No. 2017QN024)

Citation

@article{Liao2026Diurnal,
  author = {Liao, Enhui and Liang, Shiyu and Wang, Fengping and Yang, Wenchang and Zhang, Jiaxu and Lu, Wenfang and Jo, Young‐Heon and Du, Yan and MacGilchrist, Graeme A.},
  title = {Diurnal sea surface temperature amplification enhances surface extremes during marine heatwaves},
  journal = {Communications Earth & Environment},
  year = {2026},
  doi = {10.1038/s43247-026-03841-0},
  url = {https://doi.org/10.1038/s43247-026-03841-0}
}