ARS | Publication request: EVALUATION OF A TWO-LAYER MODEL FOR USE IN REMOTE SENSING STUDIES OF SOIL WATER CONTENT

Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: May 16, 2000
Publication Date: N/A

Technical Abstract: Remote sensing experiments have demonstrated that near-surface (0-5 cm) soil water content can be estimated over large areas using passive microwave sensors such as those deployed during the Southern Great Plains 1997 (SGP '97) hydrology experiment. However, these near-surface, remotely sensed soil moisture estimates need to be linked to the soil moisture in the remainder of the root zone to be useful to water resources managers an researchers in the agricultural, hydrological and meteorological sciences. Ragab (1996) developed a simple two-layer soil water budget model to predict volumetric water content of both the near-surface and bulk (root zone) layers from meteorologic data, limited soils information and initial estimates of near-surface and bulk layer soil water content. We evaluated the two-layer model for potential application in remote sensing based assessments of soil water content in tall grass rangelands of the Southern Great Plains of the U.S. We first used field (point) data to evaluate the correspondence of modeled and measured soil water contentfor four study sites. Then, in an analagous manner, we used remotely sensed (spatial) data in the model and compared model output to measured volumetric water content.