| Since the 20th century, in the context of global climate warming, extreme weather events occur frequently, the regional climate in China has undergone tremendous changes. From 1951 to 2001, annual mean surface temperature has increased 1.1℃, temperature growth rate is about 0.22℃/10a, corresponding to the average temperature increasing, a variety of extreme weather events have also changed. Using model simulating climate and forecast is an effective way, so far, there have been many results of the global climate models and regional climate model simulation were analyzed, analyses show that global climate models and regional climate models for the regional climate of China have certain simulation capability, but there are some deviations. For the limitions of the individual global climate model, including systematic bias, low spatial resolution, and mesoscale physical processes can not be described, the paper using the results of model collections of different resolution form 20 global climate models distributed by IPCC AR4, and result of high-resolution regional climate model simulated, then compared the results of global climate models and regional climate model in China. The climate factors analyzed including: annual/summer/winter mean temperature, annual/summer/winter precipitation, daily maximum/low temperature, extreme annual temperature range, frost days, heat wave during index, consecutive dry days and extreme precipitation contribution, 5 consecutive daily maximum precipitations. Mainly from the spatial distribution analysis and the time trend analysis of each characteristics, and the following are the preliminary conclusions:1. In terms of average temperature, high-resolution climate models can smulate more accurately spatial distribution of the average temperature in China, especially in the Tibetan Plateau; high-resolution regional climate model significantly improved the effect of the low-resolution global climate models; for the trend of average temperature, the result of low-resolution global climate model simulated and the mean temperature trends of observed is the nearest.2. For the extreme temperature events associated with the temperature, high-resolution global climate models and regional climate model on the effect of extreme temperature events are relatively good. Between the extreme cold and extreme heat events, the climate model simulations of extreme low temperature events better than the extreme high temperature events. In the trend of extreme temperature events, for the extreme low temperature events, the trend of extreme temperature of high-resolution climate model simulated are slightly better than low-resolution climate models; for the extreme high temperature events, the medium-resolution global climate model is better; the other models have bad effects on the trend of extreme high temperature events.3. In terms of average rainfall, the climate model ensemble simulation results on the average precipitation less than the average temperature observed, the result of various global climate model in south and west of the Tibetan plateau is more than normal rainfall, less than normal average rainfall in South China, higher resolution global climate models relative to the low-resolution climate models are batter, specially in the Tibetan Plateau, but in South China, there is no improvement, regional climate model relative to the global climate models, in the Tibetan Plateau and southern China, the simulated distribution of precipitation is more similar to observation, which joined mesoscale physical processes and more fine topography information. In the trend of the average precipitation, the result of medium-resolution global climate model simulated is closest to the average trend of precipitation observed.4. In extreme precipitation events, respecting to global climate models, regional climate model simulation is closer to observations of extreme precipitation events. Collection of global climate models, the higher spatial resolution, the better the spatial distribution of the simulation of extreme precipitation events. The trends of extreme precipitation events: in the trend of consecutive dry days, low-resolution simulations of global climate models is closest to the trend of observations, in the trends of extreme precipitation, high-resolution regional climate model simulations is closer to the observed.5. In the trend of temperature and precipitation change, the result of the global climate model simulate is smaller than observation, but the regional climate model is bigger.
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