Influence of Mississippi and Atchafalaya River plume in the winter coastal cooling of the Northwestern Gulf of Mexico
Authors: Fernandez-Novoa, D., Costoya, X., Kobashi, D., Rodriguez-Diaz, L., DeCastro, M., Gomez-Gesteira, M.
Published in: Journal of Marine Systems (2020)
Abstract
Sea surface temperature (SST) variability was analyzed in the Northwestern Gulf of Mexico over the period 1982-2018. This analysis was carried out by the combination of reanalysis databases (OISST 1/4 and CFSR) and a hydrodynamic model (ROMS). SST warming is detected throughout the year with the exception of the Louisiana-Texas shelf where a cooling is observed during winter months (November-February). The existence of a different SST trend near coast with respect to open ocean is related to Mississippi and Atchafalaya River plumes. The bigger differences, between plume area cooling and ocean warming, are detected under the plume reinforcement driven by an increment in the freshwater discharge. The plume reinforcement increases the stratification and reduces the vertical mixing, favoring the atmospheric cooling of coastal SST during winter.