山东半岛冬季冷流暴雪的气候特征及其成因征兆

Climatic characteristics and causality of cold air-outbroken snowstorm events in Shandong Peninsula in winter

利用山东半岛降雪资料、海温观测资料和NCEP/NCAR再分析资料,首先用EOF方法,在探讨了山东半岛41年(1965-2005年)冬季冷流降雪气候特征的基础上,重点分析了冷流暴雪的气候特征及时空分布。结果表明:山东半岛冬季冷流暴雪在文登附近有一个强正值中心,在招远附近有一个次强正值中心;降雪量在1980-1995年间呈5年左右的周期振荡,1996-2005年间呈2～3年周期振荡;山东半岛平均每年有0.9个冷流暴雪日。其次,分析了气温和海-气温差与冷流暴雪发生的关系。最后,根据山东半岛冬季冷流暴雪的3种不同的空间分布形态,建立了对应的3种冷流暴雪的500hPa环流模型。

Using daily observation of surface snowfall in Shandong Peninsula and NCEP/NCAR daily data during the winter （between November and the next February ） from 1965 to 2005 ,the climatic characteristics and spatiotemporal distribution of the cold air-outbroken snowstorm events in Shandong Peninsula was analysed based on the methods of EOF. The results show that the winter cold air-outbroken snowstorm events in Shandong Peninsula have a strong center near Wendeng and a weak center near Zhaoyuan. The snowfall exhibits quasi-periodic oscillations of 5 years from 1980 to 1995 and 2 -3 years from 1996 to 2005. The yearly average number of cold-air outbroken snowstorm events is 0.9 from 1965 to 2005, The cold air-outbroken snowstorm events have inter-annual and monthly change characteristics. The conceptual model of atmospheric circulation in relation to three distributions of cold air-outbroken snowstorm events was established by composite analysis, which are for events with center near Wendeng, for events along the north of Shandong Peninsula and for events with double centers.