8个CMIP5模式对中国极端气温的模拟和预估

Evaluation and Projection of Temperature Extremes over China Based on 8 Modeling Data from CMIP5

利用8个耦合模式比较计划第五阶段(CMIP5)模式结果,采用加权平均方法进行多模式集合,并与NCEP再分析资料进行对比分析,评估了CMIP5模式对中国极端气温的模拟效果,在此基础上,对未来极端气温进行预估。CMIP5模式对中国8个极端气温指数和20年一遇最高(低)气温有模拟能力,所有极端气温指数模拟和观测结果的时间相关均达到0.10显著性水平,20年一遇最高、最低气温模拟和观测结果空间相关系数均超过0.98。在中等排放RCP4.5情景下,未来中国极暖(冷)日数增多(减少),到21世纪中期热浪指数增加2.6倍,到21世纪末期寒潮指数减少71%,20年一遇最高(低)气温在中国地区均呈现升高趋势,局部升温幅度达到4℃。

Evaluation and projection of temperature extremes over China are carried out with 8 model data from CMIP5. Compared with the NCEP reanalysis data, multi-model weighted ensemble has a capacity of reproducing the 8 temperature extreme indices and 20-year return values of annual maximum/minimum temperature. The time correlation coefficients of all the 8 indices between multi-model ensemble and the reanalysis can reach 0.10 significance level and the spatial correlation coefficients of 20-year return values of annual maximum/minimum temperature are greater than 0.98. Under the RCP4.5 scenario, more extreme warm and less cold events are expected over China in multi-model ensemble. By the middle of the 21 st century, the heat wave duration index will be multiplied 2.6 times. At the end of the 21 st century, the cold wave duration index will decrease 71%, and the 20-year return values will increase 4 ℃ in parts of China for the maximum/minimum temperature.