Effects on circulation and water renewal due to the variations in the river flow and the wind in a Brazilian estuary lagoon complex

The Mundaú-Manguaba Estuary Lagoon Complex is located on the coast of Alagoas state in Northeastern Brazil, and consists two shallow lagoons, Mundaú Manguaba, that form a system choked lagoons which are connected to Atlantic Ocean by series narrow channels with single outlet dynamically alters its position. This study uses Hydrodynamic Environmental System, SisBaHiA® investigate how variations river discharge wind influence hydrodynamic circulation, water renewal, salinity temperature lagoons. free surface positions, obtained model, were compared positions measured at points complex, showing good agreement. analyses carried out for dry wet seasons extreme events very high freshwater discharge. channel an efficient filter reducing tidal variability inside ranges Manguaba Lagoons 90% 80% lower, respectively, as values open boundary. residence time calculated varied between 11 365 days 2 180 Lagoons, making it possible identify stagnation areas. results from salt heat transport model show prolonged period low concentrations slow recovery after rainy season; shows little spatial temporal variation.