长江中下游地区春季连阴雨-连晴天气过程的中期振荡

MEDIUM-RANGE OSCILLATION OF A CONTINUOUS RAIN-CONTINUOUS FINE MARCH OVER MIDDLE AND LOWER REACHES OF THE CHANGJIANG RIVER IN SPRING

  • 摘要: 本文对长江中下游地区1980年春季连阴雨-连晴天气过程及西风带、低纬赤道带和南半球天气系统的10个参数进行功率谱分析表明,它们都有准两周振荡的主要周期。交叉谱分析给出了连阴雨-连晴天气与10个参数在准两周振荡上的关联和相对振荡顺序。对连阴雨-连晴天气的时空背景纬圈及经圈环流的时空谱分析表明,纬向及经向环流振荡的两组传播波在准两周振荡上有较高的相干,经向传播超前于纬向传播。

     

    Abstract: In this paper the results of a spectral analysis indicate that there seems to exist a quasi-biweekly oscillation in continuous rain-continuous fine march over middle and lower reaches of the Changjian River and in almost all of ten elements, which are defined from weather systems of westerly belt, of low latitude belt and of the Souther Hemisphere in spring of 1980.The relations of the march with elements and relative sequence of these oscillations are determined from a crosse-spectral analysis between Continuous rain-continuous fine march and ten elements. The results of a space-time spectral analysis indicate that there seems also to exist a quasibiweekly oscillation in progressive and retrogressive waves of zonal circulation and of meridional circulation. There are pronounced relations both between progressive waves of zonal circulation and progressive waves of meridional circulation, and between retrogressive waves of zonal circulation and retrogressive waves of meridional circulation. The propagate of disturbances along zonal circle lags behind along meridian circle. The disturbances are spacetime background of these oscillations.

     

/

返回文章
返回