Assessing the Variability in Intensity and Width of the Loop Current Eddy High Speed Band from Airborne Ocean Surface Current Measurements

Abstract

The specific position and variability in width and intensity of the high speed band of currents associated with Loop Current Eddies (LCEs) is of significant interest to offshore operators in the Gulf of Mexico. This is particularly the case when undertaking drilling or offshore development operations and the activities may be located close to or inside the LCE. A study of the Remote Ocean Current Imaging System (ROCIS) data from May 2015 has been undertaken to provide further insight into the variability in intensity and width of the LCE high speed band. We defined the band to be limited by the 0.75 m/s (~1.5 knots) threshold, a typical limit for offshore operations in the Gulf of Mexico. Preliminary results show relevant spatial and temporal variability. The width of the high speed band ranged between ~40–100 km, depending on the state of the LCE, interactions with surrounding eddies and the geopgraphical location of the measurements. Peak speeds ranged from about 1m/s to 1.9 m/s. The shape of the speed profile across the band was also variable. Some cases presented a strong correlation with the Sea Surface Temperature (SST) front of the LCE, where speeds dropped significantly outside of the front. The identification of a few patterns of the high speed band was a promising result within the ongoing effort to derive expected relationships between LCE metrics such as high speed band witdth, intensity, LCE area and strength of the SST front.