Lesson 10. Monitoring soil moisture
Soil moisture is a key variable for understanding global water and energy budgets. It controls the redistribution of rainfall into infiltration, surface runoff and evaporation at the earth surface, and also has a strong effect on surface energy exchange. Information on soil moisture is also important for flood and drought monitoring, weather forecasting, water management and agricultural planning. The SMOS mission was designed to provide such information. However, measuring soil moisture from satellites is not trivial because of the effects that surface roughness and vegetation cover have on the signal recorded by the satellite. This lesson explains the physical principles of soil moisture retrieval from SMOS, and demonstrates some of the processing steps necessary to produce soil moisture maps from SMOS measurements.