Multi Index Comprehensive Drought Evaluation Based on the Entropy Method

Drought occurs more frequently, and it becomes one of the most serious natural disasters which impact on our country. Drought evaluation is the foundation of drought forecast, early warning and other works. Therefore, research on regional drought evaluation is very important. In order to solve the inconsistent problem of each index, this paper selects meteorological, hydrological and agriculture drought index, including continuous no rain days, precipitation anomaly percentage, standardized precipitation, moisture index, flow anomaly percentage, crop water shortage for comprehensive evaluation system construction. Then uses entropy method to construct a comprehensive evaluation index on which the drought assessment is conducted. Comprehensive drought assessment model based on the entropy method was applied in Xianyang, Shanxi Province. Evaluation results and the actual drought situation are basically the same. Studies show that, comprehensive drought assessment method based on the entropy is easily calculated, intuitive, with better accuracy. The method has certain credibility in drought assessment, and provides technical support for the study of regional drought.