77 / 2023-07-28 14:29:40

Interactions between cold cyclonic eddies and a western boundary current modulate marine heatwaves

Marine heatwaves, Western Boundary Current, East Australia Current, Cyclonic eddies

Marine heatwaves (MHWs) are known to cause severe ecosystem damage and therefore have received significant attention in recent years. However, the focus has tended to be on global (surface) studies, but not coastal waters, where complex coastal dynamics can drive or modulate MHWs. Cyclonic eddies are important and underappreciated components in the eddy-dominated Western Boundary Current (WBC) system, but their impacts on the path of the WBCs have largely been unexplored. Here we show the first evidence of cold cyclonic eddies modulating the most intense coastal MHWs on record inshore of the East Australia Current. We show that the MHW was driven and modulated by the lateral movement of the WBC jet and a cyclonic eddy. This study provides new insights into the interplay of cyclonic eddies and a WBC, paving the way for future investigations into eddy interactions and the evolution of coastal MHWs in other WBC regions.