Spatial and Temporal Pattern of Drought Hazard under Different RCP Scenarios for China in the 21^st century

Abstract. Drought is one of the most common natural disasters with significant negative impacts on socio-economic development and the natural environment. Evaluating this hazard is essential for risk assessment and management. In this study, historical climate data from 1961 to 2010 were used to determine the appropriate timescales for applying the standardized precipitation evapotranspiration index (SPEI) to evaluate drought. Simulated representative concentration pathway (RCP) 4.5 and 8.5 climate data for 2011–2099 in China was obtained from the Inter-Sectoral Impact Model Intercomparison Project (ISI-MIP). Then, the Mann–Kendall (M–K) test was used to assess the significance of drought trends. The frequency of three drought grades and duration were chosen to reflect the spatial and temporal variation in drought hazards in three time periods, 2011–2040, 2041–2070 and 2071–2099. Results indicate that 2071–2099 will face the most severe droughts, with the highest frequency (32.54 % for RCP4.5 and 32.55 % for RCP8.5) and longest duration (3.93 months for RCP4.5 and 4.12 months for RCP8.5), followed by 2041–2070 and 2011–2040. In terms of spatial distribution, drought hazards in north China (Medium temperate zone, Warm temperate zone and Plateau temperate zone) will be greater than in south China, especially the non-monsoon region. Comparing the two scenarios, drought hazards from RCP8.5 are higher than that from RCP4.5, i.e., higher frequency (32.35 % for RCP8.5 and 32.26 % for RCP4.5), longer duration of drought (3.84 months for RCP8.5 and 3.76 months for RCP4.5) and more significant drying trends. These results provide a reference for adapting to extreme climate change and the prevention and reduction of disaster risks.