Drivers of persistent marine heatwaves in the Mediterranean in recent years

The Mediterranean basin has experienced several marine heatwaves (MHWs) over the last few decades. During MHWs anomalous warm ocean temperatures are present for several days at least and can influence atmospheric circulation and negatively affect ecosystems. There is increased interest in these events as they occurred more frequently and with larger severity, fuelled by global warming trends. Here we examine the strong Mediterranean MHW of 2022, which started in May and lasted for several months. This MHW event rapidly spread through western and central Mediterranean with peak intensity at par with the record-breaking 2003 event. In this communication we focus on the drivers of the prolonged 2022/2023 case which led to its exceptional duration. We find that persistent anticyclonic conditions, that continued through fall and winter, were responsible for the persistence of the 2022/23 MHW. We also discuss recent Mediterranean conditions by analyzing near real-time observational products, and discuss the possible impacts of global warming on MHW characteristics.