OLR 低频振荡与西太平洋台风的发生

以影响我国西太平洋台风生成区域平均的OLR演变曲线为基础，对1975—1981年经过30—60天滤波处理的OLR场进行合成分析。结果表明，与西太平洋台风生成有关的系统，主要集中于东半球60°E以东的低纬地区。西太平洋和孟加拉湾南部的赤道地区构成一对低频偶极中心，它们之间有密切的联系。赤道印度洋中部地区是OLR低频振荡的一个重要源区，台风多发、间歇和转换阶段都有明显的特点，对台风的生成和间歇的中期预报有一定的参考意义。特别是夏季形势建立后，在30°N附近副高的东西摆动（有明显的低频变化特征）与ITCZ的变化

Relationship Between OLR Low-frequency Oscillations and the Formation of Typhoon over the Western Pacific

The composite analyses were completed of the 30–60 days filtered OLR data during the six years of 1975—1977 and 1979—1981 based on the evolution of the average OLR over West Pacific where typhoon generates frequently. The results show clearly that the systems concerning the typhoon formation are mostly located over the low latitude regions in the Eastern Hemisphere (to the east of 60°E). Some clear characteristics are found for the different stages, i., e. the frequency formation, the intermission of typhoon and the transition stage, respectively. These results will be useful to the medium range forecast of the typhoon formation.