Large-Scale Drivers of Marine Heatwaves Revealed by Archetype Analysis

Abstract Extreme oceanic events, such as marine heatwaves, can have disastrous impacts on ecosystems and marine industries. Given their potential consequences, it is important to understand how broad-scale climate variability influence the probability of local extreme marine events. Here, for the first time, we employ an advanced data-mining methodology, archetype analysis, to identify large scale climate drivers and teleconnections that lead to marine extremes in certain regions. This methodology is applied to the Australasian region, where it identifies instances of anomalous sea-surface temperatures, frequently associated with marine heatwaves, as well as the broadscale oceanic and atmospheric conditions associated with those extreme events. Additionally, we use archetype analysis to assess the ability of a low-resolution climate model to accurately represent the teleconnection patterns associated with extreme oceanic temperatures, and discuss the implications for the predictability of these impactful events.