Marine and Atmospheric Forecast Computational System for Nautical Sports in Guanabara Bay (Brazil)

An atmospheric and marine computational forecasting system for Guanabara Bay (GB) was developed to support the Brazilian Sailing Teams in the 2016 Olympic and Paralympic Games. This system, operational since August 2014, is composed of the Weather Research and Forecasting (WRF) and the Regional Ocean Modeling System (ROMS) models, which are both executed daily, yielding 72-h prognostics. The WRF model uses the Global Forecast System (GFS) as the initial and boundary conditions, configured with a three nested-grid scheme. The ocean model is also configured using three nested grids, obtaining atmospheric fields from the implemented WRF and ocean forecasts from CMEMS and TPXO7.2 as tidal forcing. To evaluate the model performances, the atmospheric results were compared with data from two local airports, and the ocean model results were compared with data collected from an acoustic current profiler and tidal prediction series obtained from harmonic constants at four stations located in GB. According to the results, reasonable model performances were obtained in representing marine currents, sea surface heights and surface winds. The system could represent the most important local atmospheric and oceanic conditions, being suitable for nautical applications.