Analysis of Ocean Current Observations in the Northern Veracruz Coral Reef System, Mexico: 2007-12

The Veracruz Coral Reef System (VCRS) is a marine protected area located on the continental shelf of Veracruz, in the SW Gulf of Mexico, that is formed by two reef conglomerates: one to the north, in front of the Port of Veracruz, and one to the south, in front of the Anton Lizardo tip. To characterize the currents and their variability for the northern reefs of the VCRS, ocean currents, meteorological parameters, and sea-level observations for the period 2007-12 were analyzed. The temporal variability of the currents was dominated by 2- to 10-day lasting events associated with the atmospheric synoptic conditions through the forcing of the along-coast wind-stress component over the Tamaulipas-Veracruz shelf. During autumn-winter, strong episodic southeastward currents prevailed, reaching more than 1 ms(-1), and they were associated with the intrusion of atmospheric high-pressure systems into the Gulf of Mexico. However, some episodes of strong southeastward currents observed in spring-summer were forced by low-pressure systems (tropical storms). From May to August, weak northwestward currents were predominant, with speeds lower than 0.40 ms(-1). Annually, southeastward (northwestward) currents were observed 45-60% (40-55%) of the time, with an average of 55% (45%). Tidal currents are one order of magnitude weaker than the wind-driven currents. A multiple linear regression model for the along-shelf currents, which is based on the wind stress, explains most of the observed variance and performs well in reproducing the autumn-winter strong southeastward events but underestimates those observed in summer.