Picture: Ocean sunset. Credit: Johannes Plenio (Pexels)

Marine heatwaves are extreme warm events in the ocean that can have severe impacts on ecosystems and fisheries. Recent studies have shown that these events are projected to increase in frequency and severity in the future. However, the reasons behind these changes have primarily been investigated in coarse resolution climate models that are unable to resolve important ocean processes.

This study uses a high‐resolution climate model to investigate how and why marine heatwaves would change for the Australian region. The relative impacts of increases on background ocean temperature and changes to intrinsic temperature variations are compared.

Variability changes are most prominent close to Tasmania, linked to a strong future intensification of the East Australian Current. Waters around New Zealand are also affected, with this shift linked to changes in heat fluxes from the atmosphere. These results highlight the indirect impacts of future temperature increases on marine heatwaves characteristics.

  • Paper: Misra, R., Sérazin, G., Meissner, K., & Gupta, A. S. (2021). Projected Changes to Australian Marine Heatwaves. Geophysical Research Letters, 48, e2020GL091323. https://doi.org/10.1029/2020GL091323