Characteristics analysis of drought at multiple spatiotemporal scale and assessment of CMIP6 performance over the Huaihe River Basin

Abstract

Study regionThe Huaihe River Basin is located in China’s north-south climate transition belt, where massive droughts occurred in history. Study focusTo comprehensively capture how climate extremes have behaved in the past, this paper analyzed the trend, change point, and periodicity of drought at multiple spatial-temporal scales based on the Standardized Precipitation Indexes (SPI). And the historical simulation experiments of 9 CMIP6 models were evaluated against observations for further exploring the behavior of climate extremes in future periods. New hydrological insights for the regionThe period of SPI-12 lies around 2–7 years, while the period of SPI-3 is at the time scale of 1–3 years, indicating potential teleconnections with large-scale climate events. Moreover, MIROC6 and CESM2 models exhibited better performance in simulating precipitation than individual models and multi-model ensemble mean. The uncertainties of the model ensemble mean of 3 selected models in depicting droughts have a good consistency with the observations. The projection experiments of CMIP6 derived from the selected historical simulation models can be used to predict drought in the near future and the far future under different scenarios over the Huaihe River Basin.