Upwelling by Surface Gravity Waves

Three upwelling mechanisms are compared that involve progressive surface gravity waves. In all cases water is pumped up from the depth of wave influence. Two of the methods that are not fully discussed in print before can occur in nature. During wind generation of surface waves in the open sea wave amplitudes and the Stokes drift increases in the direction of wave propagation implying that the Stokes drift is divergent and requiring, as a consequence, that mass be supplied to the surface from below the wave layer. The depth of wave influence of wind generated swell can reach below the light zone, so nutrients can be brought up into the sunlight and biological activity enhanced and global warming ameliorated. A third method for shallow water is the oscillation of a paddle hinged and fixed to the bottom and moved by surface waves passing by.