Integrated drought vulnerability and risk assessment for future scenarios: An indicator based analysis

The dynamic interplay between climate change and socioeconomic development has brought about significant changes in drought hazard, vulnerability, and risk within the global socioeconomic system. However, there is a prevailing lack of understanding about how these changes will manifest in an increasingly globalized economy under global warming. To address this knowledge gap, this study utilizes various climatic, geographical, and socioeconomic data from historical period and future projections to comprehensively map and assess the changes in global drought vulnerability and risk of population in the 2030s and 2050s under the SSP126, SSP245, and SSP585 scenarios. This study finds that the future population at risk of drought is projected to increase by 21.96 % - 25.95 % in the 2030s and 36.64 % - 45.40 % in the 2050s, driven by rapid population growth and substantial changes in drought hazard and vulnerability. This includes varying increases in drought hazard in approximately 58 % of global land area, alongside decreases in drought vulnerability in 50 % - 80 % of global land areas. Most arid and semi-arid regions, including Africa, Central Asia, West Asia, and Australia with less developed economies, are more susceptible to the adverse effects of climate change, leading to significant increases in future drought hazards, vulnerability, and risk, particularly under higher emission scenarios. In contrast, most humid and semi-humid regions exhibit varying degrees of drought vulnerability and risk of population across regions, despite the overall increasing drought hazard, with disproportionate impact of climate change and socioeconomic development. Specifically, projected increases in drought vulnerability and risk are observed in the Amazon, central and western U.S., while decreases are projected in the eastern part of China delimited by the Hu Line, southern India, Japan, Korea, most of Southeast Asia, northern Europe, and South America excluding the Amazon. The eastern U.S. is expected to experience reduced vulnerability but increased drought risk. This study can assist decision makers to develop targeted strategies and measures of adaptation and mitigation in an increasingly globalized economy under global warming.