Evolution law of compound drought and heatwave events in the upper Yellow River basin based on CMIP6 coupled WRF

The Compound Drought and Heatwave event is more destructive than the traditional extreme weather e-vent, and it has developed rapidly all over the world in recent years. By which, the upper Yellow River basin is particularly affected as a climate sensitive area. It is of great significance to describe its characteristics and analyze the future evolution trend for event prevention and control. In this paper, a dynamic downscaling method of future meteorological data based on CMIP6 coupled with WRF is proposed. The Compound Drought and Heatwave events and their characteristics under different scenarios in the upper reaches of the Yellow River are identified, the difference between the compound event and the single event is revealed, and the future evolution law of the Compound Drought and Heatwave event is analyzed. The results show that; (1) compared with the single event, the temperature of the Compound Drought and Heatwave event in the historical period, SSP245 and SSP585 scenarios increases by 3.8%, 13.1% and 13.5%, while the drought index decreases by 5.8%, 2.6% and 2.6%. (2) Under the SSP245 scenario, the characteristics of the Compound Drought and Heatwave event are high in the southwest and low in the northeast, while in the SSP585 scenario, the distribution in the north and east is the highest. (3) In the future, the characteristics of regional Compound Drought and Heatwave events show a significant upward trend, in which the rising trend of SSP585 is higher than that of SSP245. © 2024 International Research and Training Center on Erosion and Sedimentation and China Water and Power Press. All rights reserved.