Humboldt (Peru–Chile) Current

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The eastern boundary current of the South Pacific subtropical gyre, running north along the coast of Chile and Peru. It is cold for its latitude, and the reason is not the current itself but what the wind does at the coast: alongshore winds drive surface water offshore through Ekman transport, and cold, nutrient-rich water rises from a few hundred metres to replace it. The result is the most productive upwelling system in the world. The northern Humboldt system off Peru holds the largest single-species fishery ever recorded, on the Peruvian anchoveta, and the wider system has in some years supplied on the order of 15 per cent of the global fish catch from about 0.1 per cent of the ocean surface.