Found a much smaller garbage patch in the SW Caribbean recently. We were about 100 miles from the western end of the San Blas Islands in Panama and ran into a large region of sargasso weed and plastic. Took us several hours to cross it. Apparently the currents from the east swirl here and plastic comes from all over the Caribbean until it finally is carried west along the coast of Colombia and Panama. Nasty looking to be sure.
In South Africa doing lots of boat stuff. Departure north from Cape Town around December 15th. Arrival in the Caribbean around the beginning of February, after 5300 miles or so.