Extreme climate events and agricultural climate indices in China: CMIP5 model evaluation and projections

This study evaluates the 14 global climate models in the Coupled Model Intercomparison Project Phase 5 in capturing the extreme climate events and the agricultural climate indices over China. Future climate event changes in different Representative Concentration Pathway scenarios in China are projected using the Reliability Ensemble Average method. The models can simulate the basic spatial distribution characteristics of indices and simulate temperature indices better than precipitation indices. The models overestimate the number of wet days over China, which is related to the tendency that rainfall is simulated too often and too lightly in models. The underestimation of the number of very heavy precipitation events is detected in most models, while overestimation occurred in northern China and the Qinghai-Tibet Plateau region. Some factors, such as the complex topography, the moist convection schemes in models, and the ability to simulate large-scale circulation, may result in the performances for precipitation. Higher active accumulated temperature and more summer days are projected, while the accumulated negative temperature and frost days are projected to decrease with the warming climate. Northern China would become wetter when the number of wet days (R1mm) increases. Extreme wet events are projected to be more probable in South and Central China and the Southwest Region, with increases in very heavy precipitation days (R20mm) in all scenarios. These changes in extreme climate events and agricultural climate indices would inevitably affect agriculture in China.