Towards a 3D Hydrodynamic numerical modeling system for long term simulations of the Río de la Plata dynamic.

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Carolina Martínez, Juan Pablo Silva, Ernesto Dufrechou, Pablo Santoro, Mónica Fossati, Pablo Ezzatti, Ismael Piedra-Cueva

Friday 3 july 2015

11:00 - 11:15h at Central America (level 0)

Themes: (T) Water resources and hydro informatics (WRHI), (ST) Management support systems and serious gaming

Parallel session: 15H. Water resources - Serious gaming

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In order to support water management decisions involving characteristics of the Río de la Plata current fields, a 3D hydrodynamic baroclinic numerical model has been implemented. Further, considering that the meteorological tide in the Río de la Plata, mainly resulting from the atmospheric processes acting over the continental platform and over the adjacent oceanic region, represents the 50% of the tidal energy (Santoro et al, 2013) a nested system is then defined. Firstly, a 2D South Atlantic hydrodynamic barotropic model forced by NCEP reanalysis winds and the astronomical model FES2004, called ‘AStide’ is implemented and calibrated, taking the quality in the representation of the water level oscillations at the mouth of the Río de la Plata as the calibration condition. Secondly, a 3D hydrodynamic baroclinic model, with ten vertical sigma layers, forced for fluvial discharges, ECWMF reanalysis winds and boundary conditions from the AStide model, called ‘RPtide’ is implemented and calibrated. The main bathymetry gradients and coastal structures are captured with a spatial horizontal resolution of 0.02º. Water level, velocity profiles and salinity time series, measured at several monitoring stations in the Río de la Plata, were used to calibrate and validate the hydrodynamic model. The computational tool used for the simulations is based on the MOHID water system (Mateus and Neves, 2013) and was developed with the aim of achieving a good quality in the dynamic representation while maintaining independence in the execution and efficient computation times. In order to improve the performance of the tool, several HPC techniques were applied, achieving speedups of up to 2x, while further improvements on the computational schemes used in the model allowed a 25% reduction in the running time. The proposed tool was used and validated, based on a hindcast strategy using the MOHID water system, in the evaluation of the potential energy of tidal currents in the area. Mateus M, and Neves R. (eds.). Ocean modelling for coastal management – Case studies with MOHID. IST Press 2013. Santoro P, Fossati M, & Piedra-Cueva I. Study of the meteorological tide in the Río de la Plata. Continental Shelf Research, 60, 51-63. 2013.