两次冷涌过程的分析

本文利用两次船舶航行实测资料及部分常规观测资料研究了两次冷涌过程的时—空结构。除进一步证实了冷涌具有重力波特征的论点外,还得出了几点初步结论:(1)这两次过程前缘的传擂速度为20—2米秒~(-1),很接近重力内波波速的动力气象理论值;(2)某海区冷涌到达之前的大气层结决定了冷涌是否具有重力波特征:(3)以重力波传播的冷涌比平流移动的更有效地把能量传至低纬洋面。

AN ANALYSIS OF TWO COLD SURGES

Using the observations from two marine surveys and some conventional sources,temporal-spacial structure is analysed for tow cold current surges. In addition to confirming the argument that cold surges are characterized by gravity waves,the work concludes that:(1) The 20-25m/s of the front edge propagation for the surges is close to the theoretical speed for internal gravity wave;(2) The distribution of skew-T and log-P in the atmosphere before the arrival of cold surges determines whether or not a cold surge will behave like gravity wave;(3) Cold surges propagating like gravity wave transport energy to lower latitude oceans more efficiently than those moving in the manner of advection.