Impacts of ocean currents on the South Indian Ocean extratropical storm track through the relative wind effect

Abstract This study examines the role of relative wind (RW) effect (wind to ocean current) in regional circulation and extratropical storm track South Indian Ocean. Comparison two high-resolution coupled model simulations with/without RW reveals that most conspicuous response is significant weakening overly energetic anticyclonic standing eddy off Port Elizabeth, Africa, a biased feature ascribed upstream retroflection Agulhas Current (AC). opens pathway through which AC transports warm salty water mass from subtropics, yielding marked increases sea surface temperature (SST), upward turbulent heat flux (THF), meridional SST gradient region. These thermodynamic dynamic changes are accompanied by robust strengthening local low-tropospheric baroclinicity baroclinic wave activity atmosphere. Examination composite lifecycle synoptic-scale storms subjected high THF events indicates far downstream. Energetics calculations for atmosphere suggest energy conversion basic flow chief source increased available potential energy, subsequently converted kinetic providing growth transient waves. Overall, results mechanical thermal air-sea interactions inherently inextricably linked together substantially influence tracks