地球自转速率和大气环流

THE RATE OF ROTATION OF THE EARTH AND THE ATMOSPHERIC CIRCULATION

一、引言很多作者对地球自转速率的变化进行了分析研究,得出地球自转速率变化的周期谱,并对速率变化的机制进行了探讨。引起地球自转速率变化的因素很多,有地球内部物质的运动,有地球表面物质(如气团、水等)的迁移,及其运动速度的变化产生的影响。上海天文台罗时芳同志用最大熵功率谱的方法分析了地球自转速率变化的周期谱。

We have discussed the relationship between the rate of rotation of the Earth and the atmospheric circulation for the 500mb level in the Northern Hemisphere. Their laws of change are very similar. Both have annal and simi-annual terms. The zonal wind velocity in Dec. Jan. and Feb. is larger, and the rate of rotation of the Earth is slower, whereas those in July and Aug. are just the opposite. The calculated annual amplitude of the rate of rotation of the Earth excited by the change of zonal wind velocity is consistent with the observed value in order of magnitude, and the mean phase of the annal term of the rate of rotation of the Earth is delayed about 7 days.