【摘要】 本文用1978年12月10日至1979年1月10日的资料,对西南太平洋地区多台风及少台风活动时期的南、北半球环流形势作了分析。发现:多台风活动时期北半球东亚地区出现经向环流型,东亚的强冷空气活动可以引起西北太平洋上的东北信风潮,这股东北气流越过赤道后,能导致西南太平洋低纬地区赤道西风加大,形成强而稳定的辐合带(ITCZ)。这时台风容易生成,如高空环流条件也有利于台风的发展,就会出现ITCZ中多台风相继发生的过程。当少台风活动时期,东亚为纬向环流,西南太平洋上赤道西风及ITCZ也弱。更多还原

【Abstract】 Based on the data from Dec. 10th 1978 to Jan. 10th 1979, the circulation patterns of Southern and Northern Hemispheres during the active and inactive periods of typhoon activity over Southwest Pacific have been studied. It is found that during the active periods the circulation of Bast Asia was essentially meridional. A strong northeast trade surge over Northwest Pacific would be produced by a strong cold air outbreak in East Asia. After this northeast current moved southward and had crossed the equator, the equatorial west wind over Southwest Pacific was intensified and a strong and steady ITCZ could be formed. At this time, a typhoon is likely to be generated. If the upper level circulation is favorable for the development of typhoon, several typhoons will be formed successively in ITCZ. During the inactive period, the circulation of East Asia is essentially zonal and the ITCZ over Southwest Pacific is weak.更多还原