A Warmer, Wetter and Less Windy China in the Twenty-First Century as Projected by a Nested High-Resolution Simulation Using the Weather Research and Forecasting (WRF) Model

The identification of possible future climate change under global warming is essential for China, which has the largest population and a vulnerable ecological environment. As such, high-resolution climate simulations are important for understanding the regional-scale impact of climate change and variation such as heat extremes and drought. In a previous paper (Yu et al. in Climate Dynamics 45: 2013–2031, 2015), a high-resolution simulation using the Weather Research and Forecasting (WRF) model (forced by the Model for Interdisciplinary Research On Climate (MIROC5) 6-h outputs in the context of phase 5 of the Coupled Model Intercomparison Project (CMIP5)) was validated with observation. In this study, the near-term (2016–2035), mid-term (2046–2065) and long-term (2080–2099) future climate projections are explored by focusing on temperature, precipitation and surface wind speed. Under the Representative Concentration Pathways 6.0 (RCP6.0) scenario, the national mean annual temperatures are expected to increase by 0.9 (0.93), 1.71 (1.78), and 3.3 (3.29) °C in the early, middle and late twenty-first century in the MIROC5 (WRF) simulation, respectively, with different spatial and seasonal features in the WRF simulation. Specifically, temperature is projected to increase more slowly in winter but faster in summer, which might lead to more frequent summer extreme hot events in the WRF results. Precipitation is expected to generally increase in the future, with the national averaged precipitation increasing by 4.13 (6.54), 5.65 (6.99) and 13 (12.85)% in the three periods in the twenty-first century. The amplitudes of precipitation change in the late twenty-first century are twice those of the previous two periods, thus indicating more extreme rainfall events at the end of this century, especially in summer time. The surface wind speed in the future is projected to decrease over China in both the MIROC5 and WRF simulations for the annual mean case, but in summer, these values are expected to increase in the eastern region of China. The results are generally consistent with the previous high-resolution projection simulations over China but offer projections of surface wind speed that were rarely investigated in earlier studies.