聖嬰與反聖嬰期間西北太平洋侵台颱風之氣候特徵

The climatic characteristic of typhoons impacting Taiwan over the western North Pacific during El Niño and La Niña

本文利用1951－1998年日本氣象廳的颱風資料庫，分析聖嬰與反聖嬰現象對西北太平洋地區侵台颱風的影響。研究發現與正常月相比，侵台颱風資料在聖嬰月顯示個數及比例較少，颱風形成後侵台率較低；強烈颱風的比例較高約65%，而強颱形成後侵台率相當；形成位置較偏東南，離台灣較遠；颱風強度較強、持續時間較長及累積氣旋動能較多。與正常月相比，侵台颱風資料在反聖嬰月顯示個數及比例較少，颱風形成後侵台率較低；強烈及中度颱風合佔侵台颱風的比例較高，可達88%；但中強颱形成後侵台率均較低；形成位置二者接近；颱風強度較強、持續時間較長及累積氣旋動能較多。與反聖嬰月相比，侵台颱風資料在聖嬰月顯示個數及比例較高，颱風形成後侵台率較高；強烈颱風佔侵台颱風的比例較高，強颱形成後侵台率均較高；形成位置較偏東南，颱風強度較強、持續時間較長及累積氣旋動能較多。

This study is to investigate the influence of El Niño and La Niña on the climatic characteristic of typhoons impacting Taiwan over western North Pacific, with typhoon data from the Japan Meteorological Agency in 1951-1998. Compared to neutral months, in El Niño months, the data of typhoons impacting Taiwan show that number and percentage are lower; percentage of intense typhoons is higher, about 65%; rate of intense typhoons impacting Taiwan is comparable; the formed location is more southeastward, away from Taiwan; the intensity is stronger, sustained time is longer and accumulated cyclone energy is larger. Compared to neutral months, in La Niña months, the data of typhoons impacting Taiwan show that number and percentage are lower; percentage of moderate and intense typhoons is higher, about 88%; rate of moderate and intense typhoons impacting Taiwan is lower; the formed location is very similar; the intensity is stronger, sustained time is longer and accumulated cyclone energy is larger. Compared to La Niña months, in El Niño months, the data of typhoons impacting Taiwan show that number and percentage are higher; percentage of intense typhoons is higher; rate of intense typhoons impacting Taiwan is higher; the formed location is more southeastward, the intensity is stronger, sustained time is longer, and accumulated cyclone energy is larger.