Spatial and temporal variability of temperature, salinity and chlorophyll-a in the Magdalena River mouth, Caribbean Sea

Variations in the physico-chemical characteristics of estuaries, such as surface water salinity and temperature, lead to establishment gradients that are closely related with distribution nutrients suspended sediment. This affects light penetration, which turn influences Chlorophyll-a (Chl-a) concentration primary productivity. We used MODIS imagery identify spatio-temporal patterns sea salinity, Chl-a concentrations from 2003 2017, explore relationships between these variables oceanographic factors, streamflows, winds currents mouth Colombia's Magdalena River, discharges Caribbean Sea. Sea (SSS) study zone varied time space estuarine marine. Mean SSS was 10.8 ± 3.4 at Bocas de Ceniza, 28.4 0.4 Sea, horizontal gradient providing evidence for existence a plume. monthly temperatures (SST) averaged across all years were 27.6 1.5 °C 1.3 A significant, increasing trend temperature observed throughout period. Average values 3.3 1.4 mg m−3 1.2 calculated average Trophic State Index (TSI) Ceniza indicated estuary trophic state oligo-mesotrophic (30 < TSI≤40) mesotrophic (40 TSI≤50). The highest found intermediate salinities zone. Outside saline plume, there is considerable decrease (<0.5 m−3). Winds played most important role influencing chemical physical Our results emphasize importance processes on biological dynamics River mouth.