【摘要】 本文利用1951—1988年,逐月北半球500hPa月平均高度场资料,从月平均的角度对北半球阻塞形势进行了统计分析。功率谱、交叉谱分析表明,方案C、D的结果是相似的;对各区面积指数时间序列2年半(30个月左右)、1年半(18—20个月)和2—5个月的周期都是比较重要的;Ⅰ区和Ⅱ区具有较好的同位相负相关;在长、短周期段均有凝聚显著的周期存在。更多还原

【Abstract】 Using the monthly NH 500hPa mean height field data from1951 through 1988,the blocking patterns in the northern hemisphere areanalyzed statistically from the viewpoint of monthly means. Power andcross spectrum analyses show that the results from Scheme Care similarto those from Scheme D; periods of two and a half years (about 30months), one and a half years (18-20 months) and 2-5 months are all ofconsiderable importance for the time series of area index in the regions;there is a good negative in-phase correlation between Region Ⅰ andRegion Ⅱ: and periods with remarked coagulation exist in both the longand short time periods.更多还原