由於熱力參數(例如：溫度、氣壓、位溫等)是氣象雷達無法直接透過觀測獲得的資訊，因此逐漸發展出熱動力反演這項技術，主要是利用觀測得到的回波和風場，經過計算而取得與之相對應的熱力參數。Gal-Chen (1978) 首先提出使用都卜勒雷達觀測的風場資料可以成功進行熱力反演。接著在2019年，廖宇慶教授將風場資料利用變分方法，結合動量方程式和熱力方程式，發展出新的熱動力反演方法，此新方法稱為Terrain-Permitting Thermodynamic Retrieval Scheme (TPTRS)。TPTRS是可以在複雜地形上直接進行反演熱力參數的計算，改善了過去傳統方法只能用於平地的限制。 本研究主要的目的是將TPTRS應用到分析海葵颱風(2023)以及康芮颱風(2024)之結構特徵，並進行準確度評估。風場資料由廖宇慶教授研發的WInd Synthesis System DOppler Radar Measurement (WISSDOM)系統所提供，此系統是一個多雷達風場合成方法，可以獲得在複雜地形上的三維風場資料。本研究規劃兩種實驗設計，第一種是以Observation System Simulation Experiment (OSSE) 實驗架構進行，所需的資料是由數值模式模擬的理想個案所產生，目的是用定量評估TPTRS反演結果的誤差。第二種是真實個案，運用實際觀測獲得的數據進行反演，了解TPTRS應用在真實颱風個案上的可信度。使用TPTRS熱動力反演方法來了解颱風的熱力結構，未來將可進一步去探討熱力變數對熱帶氣旋發展的影響。 研究結果顯示，氣壓擾動在颱風中心為負值，且其負強度向外遞減。中心上方的可以觀察到明顯的暖心結構，而最大風速半徑則隨高度向外傾斜。此外，反演之氣壓和位溫場跟探空觀測結果幾乎一致，驗證了TPTRS熱力反演的準確性。研究結果同時可以發現反演的熱動力結構與GPS掩星觀測 (GPS-RO) 之關係。;Due to the lack of direct observations of thermodynamic variables such as pressure and temperature， alternative methods have been developed to retrieve the thermodynamic structures using wind fields derived from Doppler weather radar observations. Gal-Chen (1978) first proposed that thermodynamic structures. Liou et al. (2019) proposed the Terrain-Permitting Thermodynamic Retrieval Scheme (TPTRS) to retrieve thermodynamic variables over complex terrain. This scheme adopts a variational method for the calculations. In this study， we apply the TPTRS to obtain the thermodynamic characteristics within typhoons. The experiment consists of a test using the Observation System Simulation Experiment (OSSE) framework， followed by a real case study. In the OSSE test， we use the WRF model simulation data of Typhoon HAIKUI (2023) to generate the “observational” data needed for evaluation. Thermodynamic variables are retrieved using idealized data sets. In the real case study， we utilize wind fields of Typhoon KONG-REY (2024)， synthesized from radar observations through WInd Synthesis System DOppler Radar Measurement (WISSDOM)， a multiple-Doppler radar three-dimensional wind synthesis technique， to perform the TPTRS thermodynamic retrievals. The sounding data from the previous few hours are taken as the basic state. The thermodynamic fields of both typhoons can be retrieved over complex terrain and evaluated for their accuracy. The retrieved results show that the pressure perturbation is negative near the center of the typhoon， with its negative magnitude decreasing outward. A warm-core structure is identified in the upper levels above the center. The Radius of Maximum Winds (RMW) tilts outward with height. Furthermore， the retrieved pressure and potential temperature fields are consistent with sounding observations， validating the retrieved thermodynamic structure. It is also found that the retrieved thermodynamic structure shows the relationship with GPS-RO measurements.
