Avaliação de 6 sistemas de reanálise oceânicas no campo de correntes na margem continental brasileira com base nos dados do Programa Nacional de Boias PNBOIA

Abstract

Global ocean reanalysis models are an important tool for understanding and studying the oceans, making evaluation studies of these models at the regional scale essential. This study evaluated six global ocean reanalysis models at six points along the Brazilian continental margin, focusing on the current field, in comparison with observational data collected by ADCPs installed on buoys from the Brazilian National Buoy Program (PNBOIA). In addition, the bathymetry of each model was compared with the high-resolution global bathymetry model ETOPO. The bathymetric analysis showed that all models represent the continental shelf region well, as well as the isobath patterns at depths of up to 200 m; however, the lower-resolution models exhibited larger differences relative to the reference model in regions with strong topographic gradients and had difficulty representing small islands and promontories. To analyze model performance relative to the observed data, the statistical metrics of Pearson correlation, bias, root mean square error, and Skill Score were used. The main results indicate that there is no single model that performs best for all analyzed regions, and that spatial resolution proved to be important but not decisive for achieving better performance. In total, 60 parameters were analyzed, and the Australian model BRAN presented the best results in 29 instances, followed by the GLORYS12V1 model (25 instances)