8个CMIP5模式对中国极端气温的模拟和预估

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 Based on 8 Modeling Data from CMIP5

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 21st century,the heat wave duration index will be multiplied 2.6 times.At the end of the 21st 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.