Observations of an early Agulhas current retroflection event in 2001: A temporary cessation of inter-ocean exchange south of Africa?

摘要: The exchange of heat and salt between the South Indian Ocean Atlantic Ocean, at southern terminus Agulhas current, forms a crucial link in global ocean circulation. It has been surmised that upstream retroflections this current could produce temporary interruptions to exchange, but their impact would depend on vertical extent such duration. fortuitous presence sea research vessel now enabled us investigate an episode subsurface levels combination with remote sensing surface. We present here first situ evidence or early retroflection can extend depth well over 750 m last for 5 months. This event was likely triggered by happenstance two Natal Pulses, large cyclonic eddies inshore current. These short-circuited its Return leading shedding three rings quick succession. arrival third eddy when Retroflection still quite retracted did not lead another ring event. resulting may have had effect stalling motion towards Cape Basin. However, these are too scarce allow generic statements generation consequences, relation large-scale environmental factors. is observed withdrawal into Transkei Basin result series contingent interactions.