Projection of Future Precipitation Change over China with a High-Resolution Global Atmospheric Model

Projections of future precipitation change over China are studied based onthe output of a global AGCM, ECHAM5, with a high resolution of T319(equivalent to 40 km). Evaluation of the model's performance in simulatingpresent-day precipitation shows encouraging results. The spatialdistributions of both mean and extreme precipitation, especially thelocations of main precipitation centers, are reproduced reasonably. Thesimulated annual cycle of precipitation is close to the observed. Theperformance of the model over eastern China is generally better than thatover western China. A weakness of the model is the overestimation ofprecipitation over northern and western China. Analyses on the potentialchange in precipitation projected under the A1B scenario show that bothannual mean precipitation intensity and extreme precipitation would increasesignificantly over southeastern China. The percentage increase in extremeprecipitation is larger than that of mean precipitation. Meanwhile,decreases in mean and extreme precipitation are evident over the southernTibetan Plateau. For precipitation days, extreme precipitation days areprojected to increase over all of China. Both consecutive dry days overnorthern China and consecutive wet days over southern China would decrease.