Sea Level Response to Pressure and Wind Forcing in a Shallow Estuary: Validation of Two Barotropic Models with Tide Gauge and Altimetry Data

LAURA RUIZ ETCHEVERRY; MARTIN SARACENO

Lake Constance

Congreso; OSTST; 2014

ESA

The objective of this work is to compare the sea level response to pressure and windforcing of (i) a global barotropic model (MOG2D: Modèle aux Ondes de Gravitè 2-Dimensions) and (ii) a regional barotropic model (HamSOM: Hamburg Shelf OceanModel) in the La Plata River Estuary. The modeled sea-level response are compared andevaluated on the basis of coastal tide gauges and satellite altimetry data. The La PlataRiver Estuary, located in the eastern coast of South America at proximately 35ºS, is oneof the largest estuaries of the world. Previous studies have shown that in this extensiveand shallow region the estuarine circulation is mainly forced by the river run-off andwind variability, especially at sub-annual scales. Thus the atmospheric model correctionthat must be applied to the altimetry data is crucial in this region. Results show that withboth models the variance of the sea level is reduced in comparison with the classicalinverted barometric correction. Main differences between the models arise according tothe region: When the atmospheric correction is applied to altimetry data, HamSOMfarther reduces the sea level variance in the upper estuary. On the other hand, MOG2Dfarther reduces sea level variance in the middle and lower estuary.