A model study of the vertically integrated transport variability through the Yucatan Channel: Role of Loop Current evolution and flow compensation around Cuba

Abstract

The relationship between Loop Current intrusion in the Gulf of Mexico and vertically integrated transport variations through the Yucatan Channel is examined using models and the available observations. Transport in the model is found to be a minimum when the Loop Current intrudes strongly into the Gulf of Mexico, typically just before a ring is shed, and to be a maximum during the next growth phase in association with the buildup of warm water off the northwest coast of Cuba. We argue that the transport variations are part of a “compensation effect” in which transport variations through the Yucatan Channel are at least partly compensated by flow around Cuba. Numerical experiments show that the transport variations result from the interaction between the density anomalies associated with Loop Current intrusion and the variable bottom topography. The compensation effect is also shown to operate at shorter time scales (less than 30 days) in association with wind forcing.