A Theory of the Cromwell Current (the Equatorial Undercurrent) and of the Equatorial Upwelling

Abstract

A theory is given to account for the CROMWELL Current-the Equatorial Undercurrent. The equatorial upwelling is closely related to the Current, and a remarkable similarity between the equatorial circulation and the circulation in the coastal upwelling regions. The widths of the equatorial upwelling as well as of the CROMWELL Current the maximum speeds of the upwelling and of the CROMWELL Current, the depth of the core and the thickness of the CROMWELL Current, are all found to be explained quantitatively. The rate of change in the CORIOLIS parameter with latitude and the mean vertical stability of the waters are essential to determine those length scales of the phenomena. The easterly wind stress over the equatorial region is responsible for the processes.