1.School of Info-Physics and Geomatics Engineering, Central South University, Changsha 410083, China; 2.National Laboratory of Western China’s Environmental System, Lanzhou University, Lanzhou 730000, China
Based on experiments and theoretical reasoning, the authors have analyzed quantitatively the relationship between the desertification and vegetation index (NDVI) and the land surface temperature (LST). The combined information contained in the LST-NDVI space is extracted to form a new index, namely difference index of desertification (DDI), which is then used to identify the severity of desertification. With this index, we can easily get to know biophysical properties of the land surface.