我国月降水频数的时空特征

本文利用谱分析、因子分析及因子转动等方法对我国1951—1980年期间46个站逐月的月雨日资料进行分析。 对各站每年月雨日序列的波谱分析表明,我国大部分地区年周期的(第1谐波)振动在与其余波动比较中占绝对优势,显著地区是华北、东北、西南及华南地区,振幅最大值出现在7—8月份。 对全国各站年雨日振幅的逐年变化资料进一步作主分量分析及因子分析,对其中前六个主要因子作极大方差转动,转动后的新因子对应不同的特征气候区域,它们除具有逐年增加的气候趋势外,还具有准两年及22年左右的周期振动特征。

The spatial and tempora characterizations of monthly rainfall days over China

The spectrum analysis and factor analysis are employed in this paper for the mon-nthly rainfall days in 46 stations over China.The results of the spectrum analysis show that the first wave in the harmonic waves is preponderate in the harmonic waves, the significant areas are North, Northeast, South-west and South of Chain, and the maxium values of amplitude occure in July and August.The first six principal components, which is from the amplitude matrix of the first harmonic wave, have been rotated with maxium variance rotated technique, which have the meaningful characters corresponding to some areas in China. Their variety features with time have the increasing tendency year by year, and the periodic fluctuation with quasi-biennial and 22-year.