Equatorial Undercurrent of the Indian Ocean

(also Tareev current), a deep current in the Indian Ocean that flows eastward along the equator. It is 220–230 km wide and has an average velocity of 20–30 cm/sec; the maximum velocity is 100 cm/sec, occurring in the western part of the ocean at depths of 100–125 m. The current is most developed during the winter in the northern hemisphere, when the surface Monsoon Current is flowing in the opposite direction. The current was discovered in 1959–60 through expeditionary studies on the Soviet ship Vitiaz’. It was named in honor of the Soviet oceanographer B. A. Tareev (1931–72) in 1974.