Ground-based remote sensing of soil moisture using lower frequency microwave radiometers

The soil is the interface between the biology and geology forming the living skin of the earth, and the water in it keeps the earth alive. Timely information on soil moisture is useful to monitor and forecast agricultural droughts, wildfires, flood risk areas, landslides, etc., Soil moisture measurement using L-band radiometry is now widely accepted as the state-of-art remote sensing approach, and has been adopted by both the soil moisture dedicated satellite missions – Soil Moisture and Ocean Salinity (SMOS) and Soil Moisture Active Passive (SMAP). P-band, which is a longer wavelength measurement, provides the potential to retrieve deeper soil moisture information and to do so more accurately due to reduced soil roughness and vegetation effects. There are very few works using P-band radiometer [1,2] conducted at the USDA / Beltsville Agricultural Research Centre employing truck-mounted L-, C- and P- band radiometers.