Diurnal observations of soil moisture with passive microwave radiometers

Passive microwave radiometry experiments have typically employed a single daily observation of the land surface, usually at high spatial resolution and often at a single wavelength. There exists the potential of new information about land surface parameters by increasing the temporal resolution, decreasing the spatial resolution and by using multifrequency sensor packages. To facilitate some of these goals, a dual frequency (L and S band) single beam radiometer system (SLMR) that is capable of both truck and aircraft operation has been developed. During the summer of 1993, truck based field experiments designed to complete the calibration/verification of the instrument as well as to collect high temporal resolution data over well controlled plots were conducted. Results show diurnal multiday observations may provide a great deal of information on the state (profile soil moisture) and flux (evaporation) variables influencing the surface condition being observed