Controlling spatiotemporal chaos in a realistic El Nino prediction model

A method for controlling low-order chaotic behavior of continuous spatiotemporal systems is developed and demonstrated in a complex, realistic 3D partial differential equation model that is used successfully for predicting El Nino events in the equatorial Pacific. An unstable periodic orbit that involves a full-domain oscillation is stabilized using a feedback control applied to a single degree of freedom at a carefully chosen single ''choke point'' in space. A general criterion is presented for determining the optimal points In reconstructed delay-coordinate phase space at which to apply the feedback control.