Either of two oceanic currents (the North and South Equatorial Currents) flowing westward on either side of the equator. The equatorial currents are driven primarily by the easterly trade winds and are separated by a narrower countercurrent flowing eastward along the equator itself. Equatorial currents are relatively shallow, involving the epipelagic zone and part of the mesopelagic zone to depths of less than 500 m (1,640 ft). They are deflected by the continental landmasses in their path, usually splitting into northward and southward flows that feed other ocean currents and form part of the oceanic gyres (large-scale spiral current systems). See more at gyre.
ocean current flowing westward near the equator, predominantly controlled by the winds. Characteristically, equatorial-current systems consist of two westward-flowing currents approximately 600 miles (1,000 km) wide (North and South equatorial currents) separated by an eastward-flowing countercurrent only 300 miles (480 km) wide. Usually flowing at depths of less than 1,650 feet (500 m), equatorial currents travel at rates of 10 to 40 inches per second (25 to 100 cm per second). Equatorial undercurrents, centred on the equator at depths of 160 to 500 feet (49 to 152 m), flow eastward at rates up to 5 feet/s (1.5 m/s) and are approximately 1,000 feet (305 m) deep and 640 miles (1,030 km) wide.
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