The method of decomposing the passive microwave soil moisture using optical information

The water held in the top few centimeters of the soil is a key variable in many hydrological, geological, climatological and ecological processes. Different types of remote sensing systems are currently used to infer soil moisture at different spatial and temporal scales, each with its specific characteristics and limitations. Selecting 1km resolution optical data MODIS and 25km resolution passive microwave data AMSR-E 2 level of soil moisture product, the authors used NDVI-Ts feature space to remove the vegetation effect, and decompose the passive microwave soil moisture through a soil evaporation model. At last the authors got the 1km resolution soil moisture. Through building scatter diagram, it could be found that the relevance between the inversion result and 1km Vegetation Drought Index (TVDI) reached 0.569. At the same time, the author computed the 25m resolution relative soil moisture by using TM image and measured points, and resampled to 1km resolution. The scatter diagram showed a significant relationship. The correlation coefficient was 0.355. The quantitative results of the study still need further validation and improvement.EI