Mapping Spatial Variation in Surface Moisture using Reflective and Thermal ASTER Imagery and RADARSAT-1 SAR Imagery

摘要

The determination of soil moisture is an important parameter for a number of applications, including drought monitoring and groundwater recharge. This research compared the potential of using ASTER and RADARSAT SAR imagery to map the variation in moisture conditions in arid to semi-arid conditions. The research was conducted in two study areas: southern Africa and New Mexico. ASTER Thermal and reflective data were combined and used in the Vegetation Index (VI) - Land Surface Temperature (LST) triangular method to map the relative variation in moisture conditions in selected parts of southern Africa. Backscatter values of RADARDSAT 1 SAR Fine imagery was compared with near real-time soil moisture data and linear regression was used to develop an empirical model of the relationship for mapping soil moisture in selected parts of New Mexico. This study provides an opportunity to investigate the potential of spaceborne optical and active microwave data for soil moisture mapping in semi-arid regions such as New Mexico and southern Africa.