北京“数九”时节的气候特征及其变化分析

Analysis of the Climate Features and Their Change during the Period of "Shu Jiu" in Beijing

根据北京市观象台1971～2007年"数九"时节的逐日气象要素资料,利用统计学方法,分析了北京"数九"时节的气候特征及其变化情况。结果显示:北京的寒冷阶段在"三九"至"五九",这期间在"三九"末到"四九"初日平均气温连续4天维持在最低值-3.8℃,各"九"的极端最低气温是-18.3℃,出现在"五九"的第1天;各"九"平均气温的最低值是-3.5℃,出现在"三九",因此,最冷的时段是"三九";"数九"时节81天的平均气温在70～90年代变暖较快,其增温幅度为1.25℃.(10a)-1;各"九"平均气温随年代顺序变化亦属变暖趋势,"五九"的变暖幅度最大,达到1.38℃.(10a)-1。

Using daily meteorological factors of the meteorological observatory from 1971 to 2007 during the period of "Shu Jiu" (the nine periods following the winter solstice) in Beijing ,on the basis of the statistical method,the climate features and the change during the period are analyzed. The results reveal that the cold stage in Beijing happens from the third period to the fifth period. From the end of the third period to the start of the fourth period,the average temperature is 3.8 degrees below zero which is...