Empirical Models of the Loop Current Eddy Detachment/Separation Time in the Gulf of Mexico

摘要

Eddies pinching off the Loop Current can have a significant impact on offshore exploration and production activities in the Gulf of Mexico. Advance knowledge of an eddy shedding event would be of considerable value to the offshore industry and coastal and ocean engineering community that serves the offshore industry. However, imperfect understanding of the dynamics of the Loop Current eddy pinch-off has made reliable forecasting of such events elusive. Two empirical, phenomenological models are presented of the Loop Current eddy detachment/separation times based on the retreat latitude of the Loop Current and its rate of intrusion prior to eddy shedding, and the volume flow rate of the outflow in the Yucatan Channel. The models do a fairly good job of hindcasting past separation and detachment events for which observational data are available. The models also showed some skill when applied to forecasting the detachment of eddy Franklin in early June 2010, which occurred not long after the Deepwater Horizon rig explosion. However, because of the inherent limitations of the observational database available and used (e.g., its less than ideal temporal coverage and interpretational errors) and the very complexity of the eddy shedding process, the author cautions that the methodology is by no means conclusively proven. However, it is one worth continuing to explore as more and more increasingly accurate data and steadily improving understanding of the underlying physics become available in the coming decades.