热带东印度洋-西太平洋海域OLR季节内振荡空间分布特征

利用卫星观测的ＯＬＲ（Ｏｕｔｇｏｉｎｇ Ｌｏｎｇｗａｖｅ　 Ｒａｄｉａｔｉｏｎ）候平均资料（１９７９－１９９３年）分析热带东印度洋－西太平洋海域大气对流季节内振荡的空间分布特征。发现热带东印度洋－西太平洋海域（３５°Ｎ－３５°Ｓ，７５°Ｅ－１８０°Ｅ）大气对流运动的季节内振荡在４个区域中表现较明显：（１）热带东印度洋大气对流季节内振荡信号最强，显著的振荡周期集中在６．５－１２．５候；（２）澳大利亚西北洋面季节内振荡强信号主要周期表现为９．５－１５．５候；（３）澳大利亚东北洋面振荡周期集中在６．５－９．５候和９．５－１５．５候，南半球的大气对流活动季节内振荡显著区沿１０°Ｓ呈纬向带状分布；（４）南海北部、吕宋海峡附近及日本群岛以南的西北太平洋区域。ＩＳＯ振荡周期集中在６．５－１２．５候，南海南部季节内振荡周期集中在６．５－１５．５候。

THE DISTRIBUTION CHARACTERISTICS OF INTRASEASONAL OSCILLATION OF THE OLR IN TROPICAL EASTERN INDIA OCEAN-WESTERN PACIFIC OCEAN

In order to understand the distribution characteristics of the Intraseasonal Oscillation (ISO) of the atmosphere convection in tropical eastern India Ocean-Western Pacific Ocean, Iong-period pentad mean OLR (Outgoing Longwave Radiation) data (1979-1993) collected by satellite are studied using the power spectrum analysis. The results reveal that there are four regions in which the ISO signal is significant. (1) ISO signal concentrates on the Equator over the tropical eastern India Ocean. ISO period is mainly quasi-6.5-12.5-pentad; (2) ISO signal in the northwestern part of Australia appears quasi-6.5-15.5-pentad oscillation period; (3) ISO signal in the northeastern part of Australia seems complex. Both quasi-6.5-9.5-pentad and quasi-9.5-15.5-pentad oscillation periods exist; (4) The northern part of the South China Sea. Luzon Strait and southern areas of Japan arehipelago northwestern Pacific Ocean are associated with quasi-6.5-12.5-pentad; oscillations while the southern part of the South China Sea ISO period is quasi-6.5-15.5-pentad.