太平洋表層海溫之時空分佈特徵主要以年代特徵與年際特徵為主，經分析可知，太平洋高緯度地區以年代週期特徵為主，而太平洋熱帶地區除年際變化週期特徵外，亦有年代變化週期特徵。過去研究指出高緯地區海表面溫度之年代特徵透過表層環流傳輸影響熱帶地區海洋表層。因海洋垂直環流關係，存在另一個年代振盪特徵，過去較少研究探討次表層海洋之時空分布特徵與貢獻，故本研究除探討太平洋熱帶地區，年代與年際週期變化特徵外，亦探討熱帶次表層海洋對於海表面溫度及聖嬰現象之影響。近年來許多研究探討熱帶地區不同聖嬰型態之原因，其中包含表層環流改變之影響、大氣擾動之影響等，鮮少討論深層海洋之影響。在大氣與海洋之交互作用中，大氣透過進表層風場驅動海洋環流，海洋透過垂直環流改變表層與深層海洋之熱力結構，進而透過表層熱力作用影響大氣。故本研究進一步探討次表層海洋對表層海洋之貢獻，及探討其對不同型態聖嬰現象之影響。此外，本研究亦分析政府間氣候變遷委員會Intergovernmental Panel on Climate Change，簡稱IPCC)第五次評估報告所採用之耦合模式比較計劃(Coupled Model Intercomparison Project Phase 5，簡稱CMIP5)未來模擬資料RCP6.0推估未來情境資料，探討次表層海溫於未來環境中是否仍持續影響熱帶西太平洋表層海溫，進而改變未來情境下之ENSO事件。
The characteristics during annual and decadal period which are the mainly spatial and temporal distribution of sea surface temperature over the Pacific Ocean. The results of preliminary analysis show that the decadal characteristics are the main feathers in the high-latitudes Pacific Ocean. In the tropical Pacific Ocean, the characteristics are not only interannual signals but also decadal signals. In this study, we want to investigate how the ENSO events affected by decadal signals over the tropical Pacific Ocean. By the way, we also investigate how the tropical subsurface layer ocean temperature impacts on the ENSO events.The results of preliminary analysis show that the colder water in the subsurface layer ocean affect the surface ocean water through the meridional overturning circulation (MOC) in the western Pacific Ocean. The sea temperature gradient in the western and central Pacific Ocean enhanced by the surface ocean temperature cooling in the western Pacific Ocean. Through enhance the temperature gradient, it enhance the westerly strength and conducive to the development of tropical ENSO events. Since the MOC has decadal oscillation signal, we want to investigate that the influence of the subsurface layer ocean on ENSO or decadal oscillation over the Tropical Western Pacific Ocean.
