| 摘要: | 在氣候變遷之下，西北太平洋地區有颱風數量減少，強颱比例增加的趨勢。為了瞭解氣候變遷下海洋與大氣環境的變化是否對颱風強度發展造成影響，本篇研究比較過去二十年 (1980-1999年) 與現在二十年 (2000-2019年)， 6至11月的海洋與大氣環境變化，並探討氣候變遷下海洋與大氣環境的變化與颱風強度變化之間的關係。
現今氣候條件下，上層海洋環境與過去相比海表面溫度平均上升0.42℃，海水混合層深度平均加深2.7公尺，海洋熱含量增加了9.89 kJ/〖cm〗^2。結果顯示氣候變遷下，上層海洋的熱力環境將更有利於颱風強度發展。而在大氣環境方面，與過去相比，太平洋副熱帶高壓增強且向西延伸，季風槽也有西退的趨勢，垂直風切平均增加0.07 m/s，低層大氣平均比濕平均增加0.09 g/kg。結果顯示氣候變遷下，大氣環境的變化對強度發展有正貢獻也有負貢獻，太平洋副高、季風槽與垂直風切的變化將不利於颱風的生成。
分別使用觀測之颱風最大風速與環境估計之颱風潛勢強度進行分析，比較海洋及大氣環境與颱風強度的關係，結果顯示與大氣環境相比，海洋環境的變化與颱風強度變化有較直接的關係，海洋環境的變化與環境之颱風強度變化也更有關聯。其中，海洋熱含量與颱風強度的關係較海表面溫度高，並與強度較強的颱風有更高的相關性。
;Under climate change, the number of typhoons in the Northwest Pacific region will decrease and the proportion of strong typhoons will increase. In order to understand whether changes in the ocean and atmospheric environment under climate change affect the development of typhoon intensity. This study compares the changes in the ocean and atmospheric environment from June to November in the past two decades (1980-1999) and the current twenty years (2000-2019), and discusses the relationship between changes in the ocean and atmospheric environment and the typhoon intensity.
Compared with the past, the sea surface temperature has increased by an average of 0.42°C, the depth of the ocean mixed layer has deepened by an average of 2.7 meters, and the ocean heat content (OHC) has increased by 9.89 kJ/cm2. The results show that under climate change, the thermal environment of the upper ocean will be more conducive to the development of typhoon intensity. In terms of atmospheric environment, the Pacific subtropical high strengthened and extended westward, and the monsoon trough also tended to retreat westward compared with the past. The average vertical wind shear increased by 0.07 m/s, and the average specific humidity in the lower atmosphere increased by 0.09 g/kg. Under climate change, atmospheric environment has both positive and negative contributions to the development of typhoon intensity, and changes in the Pacific subtropical high, monsoon trough, and vertical wind shear will be unfavorable for the formation of typhoons.
Using the observed maximum wind speed of typhoon and potential intensity to analyze the relationship between ocean and atmospheric environment and typhoon intensity. The results show that compared with the atmospheric environment, the ocean environment has a more direct relationship with typhoon intensity. Changes in the ocean environment are more related to changes in typhoon intensity. Compared with sea surface temperature, OHC has a higher relationship with typhoon intensity. Moreover, the correlation between OHC and stronger typhoon is even more higher than that of week typhoon. In conclusion, among all variables, OHC has highest correlation with typhoon intensity. |
