Marine Currents in the Gulf of Uraba, Colombian Caribbean Sea

摘要

A comprehensive study of the marine currents of the Gulf of Uraba is presented for temporal scales ranging from intertidal to seasonal. The analyses made were based on three-dimensional (3D) numerical modeling and extensive current observations. The hydrodynamic model based on the Delft3D platform included the influence of different forcings such as tide, waves, atmosphere, river discharges, and density gradients. Because field data concerning these variables are scarce for the study area, measuring campaigns, in combination with global models and databases, were used to overcome this condition. The evaluation of the model was attained by the use of unprecedented field data obtained in different climatic seasons through a mobile gauge station. This station registered instantaneous vertical profiles of flow along 1200 km with approximately 50-m spacing. This type of measurement was preferred instead of those obtained from stationary stations, because the spatial gradients of the currents were much greater than their temporal variations. The good agreement of the 3D mathematical model in the reproduction of the observed instantaneous currents supported its use in defining the marine currents in the gulf. A combined analysis of the model results and the measured currents revealed a complex circulation pattern comprising simultaneously typical estuarine circulation, one- to three-layer flows, and even inverse circulation. This flow complexity would hardly have been determined through common measurement methodologies based on stationary gauge stations.