A handful of hyper-productive fisheries provide sustenance to a billion people and employ tens of millions. These fisheries occur on the eastern edges of the world's oceans—off the West Coast of the U.S., the Canary Islands, Peru, Chile, and Benguela. There, a process called upwelling brings cold water and nutrients to the surface, which in turn supports large numbers of larger sea creatures that humans depend on for sustenance.
source https://www.lifetechnology.com/blogs/life-technology-science-news/climate-modelers-add-ocean-biogeochemistry-and-fisheries-to-forecasts-of-future-upwelling