A physical-oceanographic investigation based on field experiments and applications of a numerical model was carried out in Golfo Dulce, a fjord-like gulf at the Pacific coast of Costa Rica. Due to the nearness to equator the effect of the Coriolis force on the circulation is negligible. Cross gulf gradients are therefore mainly related to the runoff pattern, local wind and topographic effects. The upper layer is characterized by low salinity and high temperature. Local wind effects and topographic steering results in marked across gulf velocity gradients in the upper layer. Along-gulf gradients in temperature and salinity are maintained by the freshwater runoff from the four rivers in the inner part of the gulf. A three-layer current structure is dominating in the sill area while in the deeper inner part of the gulf a two-layer estuarine circulation takes place above slowly moving deep water. Rev. Biol. Trop. 54 (Suppl. 1): 147-170. Epub 2006 Sept. 30
Keywords: Golfo Dulce, salinity/temperature distribution, circulation, exchange processes, numerical modeling