On quartet interactions in the California Current system

Abstract

Abstract. Sea surface height (SSH) altimetry observations for 1992 to 2009 off California are used to show that observed quasi-zonal jets were likely driven by near-resonance interactions between different scales of the flow. Quartet (modulational) instability dominated and caused non-local transfer of energy from waves and eddies to biannual oscillations and quasi-zonal jets. Two types of quartets were identified: those composed of scales corresponding to (a) quasi-zonal jets, annual and semiannual Rossby waves and mesoscale eddies, and (b) biannual oscillations, semiannual Rossby waves and mesoscale eddies. The spectral centroid regularly shifted into the domain of low-order modes. However, the spectrum of SSHs does not demonstrate a power behavior. This says that the classical inverse cascade is absent. For a case with bottom friction, quartet instability required the existence of a certain level of dissipativity in the flow.

Optimal Combining Data for Improving Ocean Modeling

“…Note that the procedure can be also realized very efficiently on a multiprocessor computer because each non-dominated solution for the Pareto optimal is searched separately. We have fused ADCP and CTD data collected in NAVOCEANO shipboard survey based upon the California Cooperative Fisheries Investigations protocol between 1997 and 2007, and Argo float data in the California Current System [5].…”