Upscaling Ground Soil Moisture to Validate Remote Sensing Estimations: is the Simple Spatial Average a Suitable Approach?

摘要

Whereas satellite soil moisture provides global and periodic coverage of the Earth's surface with coarse to medium spatial resolution, the in situ measurements are discrete, scattered and punctual. In this work, ground soil moisture measurements from the the Soil Moisture Measurement Stations Network of the University of Salamanca (REMEDHUS) are upscaled following different approaches to match the observations provided by the Soil Moisture and Ocean Salinity (SMOS) mission, with tens km of spatial resolution. Each method led to a representative value of the soil moisture network used to validate the SMOS data. The results of the validation through the different methods showed that all of them performed in a similar way, similar in turn to the simple average.