Soil Moisture and Ocean Salinity (SMOS) data validation has been widely performed worldwide since the product became available. However, there are few studies for Brazil. This study focused on the validation of a new version of SMOS product developed by the Institut National de la Recherche Agronomique (INRA) and Center d'Etudes Spatiales de la BIOsphère (CESBIO). One of the advantages of SMOS- INRA-CESBIO (SMOS-IC) is that the product is as independent as possible from auxiliary data. The

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... ation was performed at 7 stations located in a semi-arid mesoregion of Pernambuco State, Northeast Brazil, for the year 2016. Bias, root mean square difference (RMSD), unbiased RMSD and the Pearson correlation coefficient (R) were computed between the SMOS-IC data and in situ measurements, considering only the ascending orbit (6 am local time). The results were consistent with those found in several studies, including error metrics. The correlation coefficient (r) ranged from 0.53 to 0.86 (mean 0.68) and the sensor was able to respond adequately to rainfall events. The results of this study are useful to demonstrate the need to continue validating soil moisture data obtained by remote sensors throughout the state, especially in more rainy locations.