Ocean upwellings are fundamentally the same as those described above for lakes. Seasonal thermoclines are disrupted when the temperatures of the deeper currents approach the temperatures of the surface currents. In oceans, mixing results in massive plankton blooms in the upwelling. The movement of the current carries the upwelling to a different location. For example, mixing on the Antarctic shelf fuels upwellings along the western coasts of both South America and Southern Africa.