CONTROLLING SPATIOTEMPORAL CHAOS IN A REALISTIC EL-NINO PREDICTION MODEL

A method for controlling low-order chaotic behavior of continuous spat iotemporal systems is developed and demonstrated in a complex, realist ic 3D partial differential equation model that is used successfully fo r predicting El Nino events in the equatorial Pacific. An unstable per iodic orbit that involves a full-domain oscillation is stabilized usin g a feedback control applied to a single degree of freedom at a carefu lly chosen single ''choke point'' in space. A general criterion is pre sented for determining the optimal points In reconstructed delay-coord inate phase space at which to apply the feedback control.