| 摘要: | 颱風路徑的低頻變化，常歸咎於引導氣流受到北太平洋副熱帶高壓與夏季季風的影響所造成。然而，我們的初步研究結果卻顯示黑潮暖水對大氣的影響可能會改變引導氣流，進而影響颱風的移動路徑。我們計畫使用觀測資料與數值模式，包含理想化的模式與WRF大氣模式來探討黑潮與SST梯度的經向擺盪是否會改變對流層內的西風帶，進而導致更多的颱風轉向前往(遠離)東亞大陸地區(如台灣、中國東部地區、日本與南韓)。這些模式的結果將會與觀測資料一起進行分析、比較和探討。轉入台灣北部與東海的颱風顯然是受到相當重要且明顯的原因所造成，因此本計畫徵求探討此問題的資金。在過去的三年中(2015-2017)，本團隊對所提出的研究目標皆能有良好的進展，研究成果包括6篇SCI論文，一篇是關於冬季季風與海氣耦合作用，另外5篇是颱風的相關研究：Oey et al. [2015 Clim Dyn], Sun and Oey [2015 MWR], Sun and Oey et al. [2015 Ocean Dyn], Oey and Simon [2016 JGR-Ocean], Liang et al. [2017 JGR-Atmos], Sun et al. [2017 Nature Scientific Reports]。本研究結果將可提供相關單位，經由觀察黑潮延伸流的擺盪來預報東亞地區颱風移動路徑的長期與每年之變化，因此本研究對於防災與經濟皆有重要影響。 ;Low-frequency variations of typhoon paths are often attributed to changes in the North Pacific subtropical high and monsoon through influences on the steering wind. Our preliminary study shows evidence indicating that there may exist a strong imprint of the Kuroshio on the atmosphere, which may modify the steering wind and therefore typhoon paths. We propose to use observations and numerical models, including idealized model and WRF AGCM to study whether the meridional oscillation of Kuroshio and sea surface temperature (SST) gradient will change the westerly tropospheric wind, allowing more typhoons to veer toward (away from) the East Asian continent (included: Taiwan, East China, Japan, south Korea). These model analyses will be accompanied with observational data analyses. Typhoons that veer into northern Taiwan and East China Sea are of considerable importance for obvious reasons. This proposal seeks funding to investigate this problem. In the past 3 years (2015-2017), we have made good progress in completing the proposed goals. The research has resulted in 6 SCI papers, 1 on winter monsoon and air-sea coupling and 5 about typhoon issues: Oey et al. [2015 Clim Dyn], Sun and Oey [2015 MWR], Sun and Oey et al. [2015 Ocean Dyn], Oey and Simon [2016 JGR-Ocean], Liang et al. [2017 JGR-Atmos], Sun et al. [2017 Nature Scientific Reports]. The results obtained from the proposed research are expected to be of interest to the society as well because they may be used to provide long-term and annual typhoon seasonal projections of anticipated changes in the East Asia typhoons in response to the shift of the Kuroshio Extension. |
