Drought monitoring by remote sensing in winter-wheat-growing area of China

Temperature Vegetation Drought Index (TVDI) and Vegetation Supply Water Index (VSWI) have been widely used for drought monitoring in recent years as they have clear significance in physics and they are easy to be gotten. Winter-wheat-growing area of China has been used as research region in this paper, EOS/MODIS data being used to construct those two indexes for drought monitoring during winter wheat growth in 2009. Through analyzing correlation between the two indexes and soil moistures in different depths, linear regression comparison and verification, conclusions have been drawn that both two indexes have better correlations with soil moisture in 10cm depth than that in 20cm depth, and TVDI has excellent correlation with soil moisture, but VSWI does not. As far as soil moisture being concerned for drought monitoring, TVDI surely perform better than VSWI. Furthermore, TVDI could clearly reflect the tendency of regional drought.