Numerical modeling of tidal and wind-driven circulation in the Meso-American barrier reef lagoon, Western Caribbean

The Meso-American Barrier Reef System (MBRS) is the second longest reef system in the world and the longest in the western hemisphere. Several promontories along the Belize barrier reef, including Gladden Spit, are known to attract large numbers of groupers and snappers, among other fishes, for spawning during set times of the year, mostly January-June. The fertilized eggs are buoyed to the surface and then transported by wave drift and wind-driven currents. Analysis of the circulation patterns within the lagoon is laying the groundwork for a better understanding of the transport of eggs, larvae, nutrients, pollutant, and sediment, which in turn will help coastal managers to conserve critical habitats. The numerical model implemented for the analysis of the circulation in the MBRS lagoon is the Surfacewater Modeling System (SMS v 8.0). Five simulation cases were executed, each 35 days long, to analyze the circulation within the lagoon under varying hydrometeorological conditions. The results from the five simulations show that the circulation in the MBRS lagoon is driven by trade winds, mostly trade winds, modified by tides, with little residual flow due to runoff. Under the influence of the trades, strong flows occur near Gladden Spit, initially westward into the lagoon and then southward.