A global 1-km surface soil moisture product from 2000 to 2020

Soil moisture is one of the essential climate variables, and it controls the water, carbon, and energy exchanges between land and the atmosphere. Accurate and detailed knowledge of the spatial and temporal distribution of soil moisture is critical for various earth system applications. A long-term global 1-km daily surface soil moisture product has been generated from 2000 to 2020, as part of the Global Land Surface Satellite (GLASS) products suite. This product (GLASS SM) was generated mainly from the GLASS albedo, LST, and LAI products, ERA5-Land reanalysis soil moisture product, and auxiliary datasets based on an ensemble machine learning model. Site-independent validation results showed that the median unbiased RMSE and R for the model was 0.052 m³/m³ and 0.74, respectively.

Data values contained in the GLASS SM product represent the volumetric water content of the uppermost soil layer (0–5 cm). The files are stored in the Sinusoidal projection and provided in Geo Tiff format. “Nodata” value is set to -9999.