Drought monitoring based on the changes of water area in Dongting Lake

The drought monitoring by remote sensing technology has advantages than traditional ground monitoring. Up to now, most researches on drought monitoring are focused on constructing the relationship between parameters of remote sensing and land surface. Most current models are complex and indirect, instead, the water area directly reflects drought situation especially in the region where the irrigation and drinking mainly depend on surface water, so it is practical to evaluate drought based on the changes of water area. In this paper, taking the Dongting Lake as an example, the extraction method of water area from images of long time serious is firstly proposed. Furthermore, the correlation between water area and water level is analyzed to validate that the water area can quantitatively indicate drought. On the basis of constructing model of water area anomaly, the approaches of identifying and verifying drought classification assisted by typical drought event in history are illustrated. The result indicates that the proposed approach is valid for monitoring drought in terms of the changes of water area.