赤道湧升流的動向一直是大家所關注的焦點。除了因為湧升流把營養物帶往海表面因而帶來豐碩的漁獲以外，其將冷水自混合層下方帶往海表，也有效減低了混合層的熱容量，和海表面溫度的變化息息相關。我們在近幾年的工作顯示，東大洋冷舌區海溫發展與衰退的演化過程，幾近完美地由赤道湧升流的起落所掌控。由此一窺，精確掌握赤道湧升流的動向，絕對是科學上與經濟上刻不容緩的重要課題。 筆者去年八月(2018/08) 被延攬為國立台灣師範大學地科所陳正達老師的博士後研究員，中途因錄取國立中央大學大氣科學系的助理教授(2019/02就職)而終止該計畫的博士後工作。為求此工作不被中斷，筆者將繼續進行當初的研究，力求完善。本研究將使用CMIP5/6的模式輸出搭配觀測資料做對照，針對赤道湧升流的季節波動與年際變化進行分析，探究赤道湧升流在模式裡的形成機制。並由海洋動力及海氣耦合機制的角度建構理論模式，希望能精確模擬赤道湧升流的變化，同時掌握冷舌區域海溫演化的過程。我們將根據研究結果，進一步探討現今CMIP5/6模式對於湧升流與海溫模擬偏差的原因，提出改善模式模擬能力的關鍵。冀望有朝一日能透過模式無限逼真地模擬出赤道湧升流與冷舌海溫的變化，使更多相關氣候問題得到解決。 ;The variability in the equatorial upwelling is always of great interest. Not only because upwelling brings the nutrient supplies to the surface and creates rich ocean productivity, but also because it takes cold waters upward and effectively reduces the heat storage of mixed layer, which makes it closely connected to sea surface temperature (SST) variations. Our recent work suggested that the strong development and rapid decline of the cold phase of the SST annual cycle is heavily affected by equatorial upwelling, hence understanding and well-estimating upwelling is a key issue from both economic and scientific perspective. We would like to explore the dynamics of upwelling using observational and modeled output, and develop a general formulation to better estimate the variability of equatorial upwelling. Regarding this issue, we will also diagnostic the cold tongue SST bias in CMIP5/6 (Coupled Model Intercomparison Project Phase 5/6) simulations and seek improvement through the coupled wave dynamics in equatorial upwelling. Hopefully we will be able to make our model performances infinitely close to reality, and further settle those relevant climate problems in the near future.
