Abstract
Horizontal divergence and vertical velocity in the surface mixed layer of the equatorial Pacific between 90° and 150°W are estimated from current measurements obtained from trajectories of freely drifting buoys during 1979–1990. The 12-year averaged horizontal divergence is predominantly meridional and has a maximum magnitude of 3–4 (× 10−6 s−1) in a 20-km-wide latitude band cantered on the equator. Using the equation of continuity, this divergence corresponds to an upwelling velocity of 1.5–2 (× 10−4 m s−1) at 50-m depth. The seasonal variations of equatorial divergence are in good agreement with the local zonal wind stress.
