Anticyclonic rings and the energetics of the circulation of the Gulf of Mexico

Abstract

The question addressed in this dissertation is what is the primary energy source for the anticyclonic gyre found in the western Gulf of Mexico. Two energy sources are considered: the Loop Current through the mechanism of the anticyclonic rings that separate from that current; and the curl of the wind stress. To resolve which of these two mechanisms dominate, the energy input into the western Gulf by each is estimated; they are then compared to each other, and to the energetics of the circulation of the western Gulf. The rings and the wind stress mechanisms are first considered descriptively, with the primary emphasis on the time and space scales of the rings and the seasonal variations in the curl [subscript tau]. Examination of existing hydrographic data shows that the rings translate into the western Gulf with a mean speed of 2.1 km/day; they have a decay time of about one year; and they are formed on the order of once per year. A typical ring diameter is 360 km; the same as the N-S length scale of the western gyre. ...