Currents

It is not only the oceans surface that is continually moving. Currents are everywhere as well, and unless we anchor they will push our platform around. Approaches to dealing with this are outlined in the Transportation section.

Currents tend to consist of large cyclical formations with opposite direction of rotation in the northern and southern hemispheres. They range in speed up to about 2.5 m/s. They are caused by a number of factors, such as wind, convection, density differences due to variations in salinity, and the Coriolis force. The chart below will give you a general feel for the arrangement of currents:

[Currently used without permission from a figure in Principles of Ocean Physics by John R. Apel, Academic Press, 1987].

However, it must be noted that these maps are deceptively simple. Ocean currents form many eddies and transient features, and vary from season to season and year to year.