Assessment of the Wind Variability on the Large Tropical Aquatic Systems: Comparison Between WRF and BRAMS Models

Abstract

Wind patterns are important in various fields of study such as pollutant dispersion, evapotranspiration, humidity, advection of heat, wind use etc. In hydroelectric reservoirs, the winds can be influenced by the surface energy balance. In this sense, meteorological data of a 10 m tower, installed on an island in the Furnas reservoir, Minas Gerais, and simulations with mesoscale meteorological models WRF and BRAMS were used to analyze wind variability. The representativeness of the models was verified from simulations for two periods under different synoptic conditions: the performance of an anticyclone and the passage of a frontal system. The results indicated that during the anticyclone operation the BRAMS was more efficient in simulating the intensity and direction of the winds, while the WRF represented better values of humidity and temperature. In the case of the frontal system, the WRF was efficient in representing all analyzed parameters, whereas BRAMS did not obtain good results for intensity and direction of the winds. The simulations showed that the relief in the reservoir region acts as a channeling agent of the winds and that the differential heating between the reservoir and the surrounding surface generates a temperature gradient and a lacustrine circulation.

Keywords

• hydroelectric reservoirs
• lacustrine circulation
• numerical modeling of the atmosphere