Ocean Currents & the Global Conveyor

Introduction

The ocean is always moving

The ocean is not a still bathtub. According to NOAA, constant motion takes the form of a global ocean conveyor belt — a combined system of wind-driven surface currents and deep, density-driven flows that together circulate heat, salt, and nutrients across every ocean basin.

The Gulf Stream carries warm Caribbean water northeast across the Atlantic at up to 2 metres per second, transporting roughly 30 times the combined flow of all the world's rivers. Northern Europe's relatively mild climate is partly a result of this heat delivery.

Ocean currents also feed ecosystems. Cold upwelling zones — where deep, nutrient-rich water rises to the surface — support some of Earth's most productive fisheries. The Humboldt Current off South America is one example; it sustains anchovy populations that feed millions of people.

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