Evaluation of the CAMS Gridded Solar Radiation Model in Brazil

Kurzfassung

This study provides an evaluation of the Copernicus Atmosphere Monitoring Service (CAMS) Radiation Service (CRS) gridded solar radiation model for the Brazilian territory, focusing on its application for detailed spatiotemporal analyses. The research validates an extensive 19-year dataset of CAMS solar radiation estimations (2005-2023) by performing a rigorous comparison against high-quality ground-based measurements from 11 stations geographically dispersed throughout the country. Beyond simple pointwise comparisons, this work critically explores the model's capability to represent complex geographical and climatic patterns through the generation of monthly solar radiation anomaly and long-term trend maps. The methodology employed a multi-step process including bilinear interpolation to align the gridded satellite data with precise station coordinates, the calculation of statistical metrics (nMBE, nRMSE) across multiple time scales, and a comprehensive seasonal analysis. The resulting maps successfully revealed significant spatial variations in solar radiation directly linked to large-scale climatic phenomena, as the El Niño-Southern Oscillation (ENSO), underscoring the utility of CAMS data for regional-scale climate studies. The conclusion emphasizes the potential of CAMS as a promising and valuable tool for solar radiation mapping, while also acknowledging the inherent challenges in fully representing highly localized atmospheric conditions. The approach demonstrates how gridded models can effectively complement and extend in-situ measurements, particularly in vast regions with limited ground data availability.