Investigation of compound drought risk and driving factors in Nepal

Accurate assessments of drought risks are essential for sustainable developments. Previous studies, though, explored drought risks often from a single perspective, e.g., hydrological and agricultural droughts, and holistic analyses have not been thoroughly investigated. To fill this knowledge gap, in this study, Nepal was chosen as the study area to assess compound drought by integrating meteorological, hydrological, agricultural, and socioeconomic droughts. Specially, precipitation, groundwater, seven crops, evaporation (ET), available water-holding capacity (AWC), gross domestic product (GDP), irrigation, international wealth index (IWI), and distance to waterways (DW) were employed as influencing factors to model drought hazard, vulnerability, and prevention. Especially, a compound drought risk assessment (CDRA) model was proposed. Moreover, the multi-scale geographically weighted regression was utilized to identify the factors influencing the drought risk under varying climate settings. Upon examination, the performance of the CDRA model was satisfactory and yielded a compelling demonstration of drought risk estimations in Nepal. Regions with high drought risks were favorably consistent with historical disaster zonings. The Pearson correlation coefficient was 0.566 compared with the standardized precipitation evapotranspiration index results. A relatively high proportion of medium- and high-hazard levels was observed in the temperature zone with a hot or warm summer, suggesting the high temperature significantly increased drought risks. A qualified total explained variance of drought risks was found in driving analyses (R 2 value = 0.679). In addition, the ranking of the influencing factors from high to low was IWI, GDP, AWC, irrigation, groundwater, precipitation, ET, and DW. It suggests that socioeconomic alleviations in wealth, inequality, and poverty are essential for drought relief. The results can provide a reference for drought mitigations for governments and communities.