On the shape of sea level anomaly signal on periphery of mesoscale ocean eddies

Abstract

AbstractGood knowledge of mesoscale eddy properties and their spatial and temporal distribution in the world ocean is important for an accurate estimate of their role in heat, salt, and/or momentum transports. Composites of satellite sea level anomaly, used to evaluate internal eddy structure, commonly produce, at larger radii, a series of rings of alternating sign. We suggest that these secondary rings are not a part of the dynamical structure of the “central” eddy but are a rectified signature of the surrounding eddies. We show that statistical distribution of eddy polarities is not random but that an eddy of given polarity tends to be surrounded by eddies of opposite polarity. This observed spatial eddy polarity distribution, which is hypothesized to be a result of eddy self‐organization, is not only responsible for the secondary rings observed in the composite estimates but also causes a reduction of around 20% of the eddy composite amplitude and an increment of around 10% in the maximum rotational velocity, while it has negligible effect on the estimated eddy scale.