Applicability of Radio Occultation Data for Atmospheric Temperature Estimation over the São Francisco River Basin

Abstract. Accurate atmospheric profiling is essential for understanding climate dynamics and improving weather forecasting, particularly in data-scarce regions. This study evaluates the performance of the Radio Occultation (RO) technique - using data from the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC-2) by comparing vertical temperature profiles with radiosonde (RSO) observations over the São Francisco River Basin (Brazil) during January and July 2020, which represent contrasting seasonal conditions. Statistical analyses, including root mean square error (RMSE), correlation coefficient, relative error, and mean differences, are applied to assess the agreement between the two datasets. Results reveal high consistency, with RMSE values below 1.6 °C, correlation coefficients exceeding 0.84, and average differences generally below 1 °C. The student’s T-test confirmed the absence of statistically significant differences at the 5% level, reinforcing the reliability of the RO-derived profiles. Such findings suggest that RO is a promising method for capturing atmospheric temperature structures, making it a valuable complementary tool for climate monitoring in regions with limited in-situ observations.