我国冬季气候数值预测潜力的初步分析

Preliminary Analysis on Numerical Potential Predictability of Winter Climate in China

20世纪80年代以来,我国南方地区先后在1984年冬季和2008年冬季发生了两次过程相似的极端天气事件。为了考察该类天气事件的气候预测潜力,分别利用中国科学院大气物理研究所的2层和9层全球大气环流模式进行了跨年度集合回报试验。结果表明,两个模式都表现出了一定的预测能力,但针对我国不同的区域和气候因子,预测能力存在差异,例如,2层模式对我国东部近地面风场异常的预测潜力相对较大,而9层模式对月平均降水距平百分率的预测能力则更为突出一些。综合两个模式的集合回报结果来看,包含该类极端天气事件的关键区月平均降水异常和近地层风场异常都具有一定程度的气候可预测性。与降水的预报技巧相比,模式对近地面风场的预测能力要更为稳定一些。

From the 1980s,there happened two similar extreme weather events in South China in winters of 1984 and 2008,respectively.Aiming to investigate the potential predictability of such extreme winter weathers in China,the extra-annual hindcast experiments are performed by using the two-level and nine-level atmosphere general circulation models developed by Institute of Atmospheric Physics,Chinese Academy of Sciences.The results indicates that the two models are capable of making reasonable prediction to a certain degree,and the prediction skills embedded in the models vary along with regions and climate factors.For instance,the capabilities of the two-level and nine-level models are more competent in predicting near surface wind anomaly and percentage anomaly of precipitation,respectively.Taken together,the recorded anomalies of monthly near surface wind field and precipitation in the key regions can be predicted to some extent.On the whole,the potential predictability of near surface wind anomaly is more steady than that of precipitation.