On the Linear Relationship between Loop Current Retreat Latitude and Eddy Separation Period

Abstract

A linear correlation exists between the retreat latitude of the Loop Current following eddy separation and the subsequent eddy separation period. This empirical relationship was first identified in satellite altimeter-derived Loop Current metrics. In this paper, a simple vorticity model of the Loop Current is used to provide a semitheoretical basis for this relationship. After suitable scaling approximations, the theory predicts that the LC separation period is a linear function of retreat latitude, which agrees well with altimeter-derived empirical results. Specifically, the predicted slope and y intercept agree to within 9% and 2%, respectively, with the altimetry-derived values.