Marine heatwaves (MHWs) are extended periods of extremely warm seawater. They can have very serious consequences both ecologically and socioeconomically. Marine management has long called for methods to forecast MHWs. Now a group of researchers have managed to use global climate forecasts “to develop and assess MHW forecasts that cover the world’s oceans with lead times of up to a year”. The researchers used 30 years of retrospective forecasts to show that the method works. They show that skilful forecasts are possible in advance at a range of 1 to 12 months.
The range is dependent not only on region and season, but also on the state of large-scale climate modes (for instance El Niño/Southern Oscillation). The authors also discuss decision thresholds, which would allow stakeholders to be proactive depending on the risk at hand. An operational use of MHW forecasts is concluded to be similar to the use of forecasts of extreme weather phenomena, and such a use is suggested to globally promote climate resilience in marine ecosystems.
Source: Jacox, M.G. et al. 2022. Global seasonal forecasts of marine heatwaves. Nature 604, 486–490. https://doi.org/10.1038/s41586-022-04573-9
