Hydrodynamic modelling in the Amazonian Estuary: A flexible mesh approach

ABSTRACT Several hydrodynamic models have been applied to the Amazonian Estuary, but its complex shape makes the grid definition difficult when a structured grid is used. This research aims to implement a hydrodynamic model for this estuary based on a flexible mesh grid system and then analyze the results. The methodology is based on Delft3D FM, and the model domain encompasses the low course of the Amazon, Tapajos, Xingu, Tocantins, and Para rivers, Guajara and Marajo bays, and Breves Strait, as well as the floodplain areas and the adjacent continental shelf. The model simulation performs well against the observed tidal water levels and instantaneous transport since Pearson’s correlation coefficient showed more significant values than 95% for both, and root mean square error (RMSE) showed smaller values than 5% for water levels and 15% for instantaneous transport. This also performs well in simulating scenarios representing different tide and instantaneous transport conditions.