A Nested Model of the Cariaco Basin: Study of the Hydrography and Interactions with the Open Ocean

The circulation of the Cariaco Basin (Venezuela) is modeled using the Regional Ocean Model System (ROMS) nested in the global 1/12 degree Hybrid Coordinate Ocean Model (HYCOM). The objective of this work is to obtain a better understanding of the Cariaco Basin circulation by studying the processes that link the basin with the Caribbean Sea. To our knowledge, this is the first attempt to model the circulation in the Cariaco Basin with a nested high resolution hydrodynamical model. In particular, we examined the interaction of the Cariaco Basin with the large-scale, open-ocean processes, as the westward Caribbean Current and the eastward subsurface counter-current flowing along the South America Caribbean coast. These two current systems connect the Cariaco Basin with the Caribbean Sea waters, and therefore are directly related to the ventilation of the basin. By studying the kinematics and dynamics of the Cariaco Basin we anticipate gaining a better understanding on how the past conditions affected the basin characteristics and hence the geological records obtained from the basin sediments. We will report on several years of observations from the continuous monitoring of currents within the basin, plus analyses of year-long model runs that provide a basin-wide, three-dimensional context for the circulation.