A research on drought monitoring model by remote sensing in the east part of Weibei of Shaanxi Province

The east part of Weibei of Shaanxi province was situated in Loess Plateau, semi-arid and and region. The soil texture of this area is very loose and easy to cultivate, so it is an important planting crops area. In this area, the change of precipitation is very large, the drought often come about, so dynamic monitoring the range and extent of drought will have important significance. This area has so much gully that the topography is very complex. On the basis of crops' growing period, this study have established a remote sensing drought monitoring model for this area by using data of NOAA/AVHRR and the meteorological observation data through applying stepwise regression method. This model has been used to dynamically monitor the spring drought in 2002. The monitoring results show that the model can express the spatial distribution with different drought levels, as well as various drought degree. The multiple correlation coefficient of drought monitoring result and the relative moisture of the soil run up to above 0.9. and the accuracy of the estimations of drought in this area is higher than only using thermal inertia method or vegetation supply water index method. The model has better prospect in applying.