大气定常波传播的运动学特征的时空变化

SPAC1AL AND TEMPERAL VARIATION OF THE KINEMATIC CHARACTERISTICS FOR THE PROPAGATION OF ATMOSPHERIC STATIONARY WAVES

中文摘要:

      利用时间平均全球大气环流资料,本文计算了纬向平均位涡的南北梯度的时空分布,以及波动水平传播的临界波数n_c,和垂直传播的临界波数K_c的时空分布。由此研究全球大气定常波传播的运动学特征及其年变化。

英文摘要:

      Time-mean global general circulation data are employed to analyse the temperal and spatial variation of the meridional gradient of zonal mean poten-tial vorticity, the critical wave number n_c for horizontal wave-propagation, and the critical wave number K_c for vertical wave-propagation. Thereby the kinematic characteristics for the propagation of atmospheric stationary waves and their annual variations are studied. Results show that in the troposphere n_c and K_c usually decrease with the increase of either latitude or altitude. Synoptic and near-resonant Rossby waves could be trapped during their upward and meridional propagations. These characteristics possess prominent annual variations, especially in the Northern Hemisphere. It is found that the spatial and temperal variations of these kinematic characteristics are in good agreement with those of the atmospheric wave patterns.