Cromwell Current

The Cromwell Current is the Pacific Equatorial Undercurrent, a narrow subsurface jet that flows eastward along the equator within the thermocline, against the westward South Equatorial Current at the surface. Its core sits near 100 to 200 meters in the west and shoals to about 40 meters in the east, with core speeds of roughly 1 to 1.5 meters per second and transport near 30 to 40 Sverdrups. The eastward pressure gradient set up by the trade winds drives it, and the Coriolis force confines it to the equator. The current was identified by Townsend Cromwell in 1952.