Based on the observational evidences that the tropical cyclones (TCs) number in the western North Pacific (WNP) in autumn is more than that in summer, this study mainly compares the disturbance of some conditions that associated with the formation of TCs between the two seasons. Results show that the most of the distributions of the disturbance field of atmospheric dynamic factor are similar, while the unique feature of the upper level geopotential height/vortex anomaly over east Asia/western Pacific sector varies greatly and may play the important role in generating more TCs in autumn. Further analyses indicate that the high-pressure/anticyclonic anomaly in autumn is originated from the north tropical Atlantic Ocean. When a cold sea surface temperature (SST) anomaly appears in north tropical Atlantic, a Rossby wave train over Eurasia continent could be induced which then leads a favorable condition for TC genesis over east Asia/western Pacific sector at upper troposphere, resulting in more WNP TCs in autumn.

基于观测证据，北太平洋西部（WNP）秋季的热带气旋数量比夏季多，本研究主要比较了两个季节之间与热带气旋形成有关的某些条件的扰动。 。结果表明，大气动力因子扰动场的大部分分布是相似的，而东亚/西太平洋区域高层地势高度/涡旋异常的独特特征变化很大，可能在产生更多的动量中起重要作用。秋季的TC。进一步的分析表明，秋季的高压/反气旋异常起源于北部热带大西洋。当北部热带大西洋出现冷海表面温度（SST）异常时，