Eddies Redistribute Ocean Warming Hotspots in the East Australian Current Southern Extension

Abstract

The East Australian Current (EAC) southern extension is one of the ocean warming hotspots under greenhouse warming, yet its underlying mechanism remains debated. Here we investigate ocean warming in the EAC southern extension based on simulations from a state-of-the-art high-resolution global climate model. In the changing climate, the EAC heat transports intensify near the coasts. However, ocean warming is substantially greater offshore than in coastal regions. Heat budget analysis reveals that this pattern is driven by oceanic eddies, which redistribute the inshore EAC heat fluxes off the coast, suppressing coastal warming while enhancing offshore warming. Under global warming, eddies strengthen the cross-shore warming structure at a rate of 1.6°C/100 km per year per century. Our result highlights the dominance of eddies in influencing the spatial structure of ocean warming in the EAC southern extension, with important implications for marine ecosystems such as coral community and coastal fishery.