Development of an integrated weighted drought index and its application for agricultural drought monitoring

Abstract

Comprehensive consideration of physical forms of meteorological and agricultural drought is necessary for the development of robust monitoring and assessment of droughts. This consideration facilitated the development and analyze an integrated weighted drought index (IWDI) by using the AHP (analytical hierarchy process) technique that takes into account all possible variables relevant to different types of drought such as meteorological, agriculture, and soil moisture drought indices. Heilongjiang northeastern province of China had suffered frequent droughts due to the changing climate. Droughts affected agricultural production and caused a decrease in total yield due to less water availability, particularly in summer which is the only growing season in the area. In this study, an integrated index was developed to examine its applicability and to assess the impact of drought on rice yield using eight different drought indices included meteorological, remote sensing multi-sensor, soil moisture conditions, and climate variables. The results showed that IWDI had a significant correlation with meteorological and agricultural drought indices. Detailed analysis revealed that, compared to a single meteorological or an agricultural drought index, IWDI achieved good results for agriculture drought monitoring. Results showed that IWDI captured a significant impact of drought on rice yield and its variation in the area which was from 17 to 75% at different stations. This study also concluded that integration of different indices may be a better option for policymakers and economists in understanding and monitoring agricultural droughts losses.