One of the present efforts in the field of microwave remote sensing is to estimate soil water status throughout the soil profile using radiometers. This study describes a simple, ideal algorithm relating microwave brightness temperature (T_B) and soil water status in the upper (10 cm) and lower (greater than 10 cm) soil depths. The algorithm description considers a simple, homogeneous, and sandy soil system with negligible amounts of capillary-stored water, organic matter content, and surface roughness. The microwave T_B was estimated from the dielectric constant, k, as a function of the amount of water remaining in the soil during drainage. The effect of downward fluxing, free water on the value of T_B was greater and occurred over a shorter period than that of the slower draining water near field capacity. The predictability of the algorithm decreased as the moisture content decreased to that of approximately field capacity.

Date Published: 30 December 1997
PDF: 6 pages
Proc. SPIE 3222, Earth Surface Remote Sensing, (30 December 1997); doi: 10.1117/12.298145

Published in SPIE Proceedings Vol. 3222:
Earth Surface Remote Sensing
Giovanna Cecchi; Edwin T. Engman; Eugenio Zilioli, Editor(s)