Soil Moisture and Remote Sensing

Soil moisture—the water held in the upper layers of the ground—controls how rainfall moves into rivers, how crops grow, and how heat exchanges between the land surface and atmosphere, making it a variable that touches hydrology, agriculture, and climate science simultaneously. Satellites equipped with microwave sensors can now estimate soil moisture across the entire globe by detecting subtle changes in the electromagnetic properties of wet versus dry soil, and researchers combine these observations with computational models through a process called data assimilation to produce continuous, physically consistent estimates. A central challenge is that satellite measurements capture coarse spatial averages, while actual moisture can vary sharply over meters due to soil type, topography, and vegetation—reconciling that mismatch between scales remains an active problem. Ongoing work focuses on improving retrieval algorithms for dense vegetation where the microwave signal is partly obscured, and on using the resulting global datasets to better predict drought onset, flood risk, and long-term shifts in regional water availability.

Works

357,076

Total citations

696,519

Keywords

Remote SensingSoil MoistureSatellite ObservationsData AssimilationHydrological ModelingGlobal Monitoring