Western boundary currents are a key part of the surface ocean circulation that transport heat and salt and thus they connect the ocean to the global climate system The Agulhas Current is the strongest western boundary current on Earth, and it flows southward along the southeast African coast. The heat and salt that “leak” into the Atlantic Ocean from the Indian Ocean at the Agulhas retroflection, where the current parts from the coast at the southern tip of South Africa and turns back to the Southern Indian Ocean. In addition to the contribution to global climate, the Agulhas Current has significant effects on regional rainfall in southern Africa.
We have been working on the proxy evidence for past changes in the Agulhas Current, correspondence with deep ocean circulation, and terrigenous sediment evidence for rainfall variability in southeastern Africa. We have used sediment cores from the Lamont Core Repository, from our CD-154 cruise (led by Ian Hall and Rainer Zahn) and from our International Ocean Discovery Program Expedition 361 (https://iodp.tamu.edu/scienceops/expeditions/southern_african_climates.html )