Influence of the Remote Forcing and Local Winds on the Barotropic Hydrodynamics of an Elongated Coastal Lagoon

Abstract

ABSTRACT Casares-Salazar, R. and Marino-Tapia, I., 2016. Influence of the remote forcing and local winds on the barotropic hydrodynamics of an elongated coastal lagoon. The main objective of this study is to investigate the effects of local winds and sea-level variations at tidal and subtidal frequencies on the water levels, depth-averaged velocities, and volume fluxes of an elongated and shallow coastal lagoon using field measurements and a barotropic two-dimensional numerical model. Tides are mainly diurnal and attenuate ~85% from the mouth to the lagoon head, indicating a barotropic propagation dominated by friction. On the other hand, the low-frequency water-level fluctuations propagate with little attenuation (~17%), dominating the water-level variability at the lagoon head. It is considered important to elucidate whether this low-frequency variability is related to local winds or to remote effects. Modeling results show that local winds can increase water levels up to ~1.9 cm in the lagoon head (5% ...