不同季節以及不同降雨型態的雨滴粒徑分佈(DSDs)特性以及降雨的垂直結構，不僅關係著降雨的微物理性質，也影響雷達定量降雨估計的正確性，本計畫將利用台灣北部過去十年雨滴譜監測網與雷達網的長期間測資料，進行不同季節的雨滴粒徑與雷達回波垂直結構的統計分析，以了解降雨之微物理性質，利用降雨強度以及雷達回波垂直結構可以將降雨區分為對流性、層狀性，以及淺對流等三種型態，並將比較不同地面雨滴譜儀(如2DVD、Parsivel、JWD等)雨滴粒徑統計特性之差異，結合雨滴粒徑與雷達回波可以建構不同季節與不同降雨型態的雷達回波定量降水估計公式，進一步則將利用雙偏極化雷達參數所建立之降雨估計關係式來進行比對與驗證。同時結合地面、探空、氣象衛星與氣象雷達特別式雙偏極化雷達支觀測探討比較不同季節與不同降水系統所伴隨之動力與降雨雲微物理過程之特性差異。本研究計畫第一年執行近五個月以來，已完成台灣北部過去十年之雨滴譜儀資料收集，特別是中大過去8年2DVD光學式雨滴譜儀資料以及中大過去十年JWD撞擊式雨滴譜儀資料之收集與格式整理，以及資料品質檢定以及與雨量觀測資料之比對，建立雨滴譜儀資料庫。並且利用五年的雨滴譜觀測資料比較分析台灣北部和帛琉兩個島嶼夏季雨滴粒徑之分布特徵以及伴隨之降雨雲物理過程和Z¬-R雷達降雨估計關係式之特徵與差異，逞果已發表在2017年12月出版之J.G.R.國際期刊上。 ;The statistical characteristics of raindrop size distributions (DSDs) and vertical structures of rainfall during the past ten years in Northern area of Taiwan are studied using measurements from a ground-based disdrometer network and radar network in the northern part of Taiwan. Based on rainfall intensity and vertical structure of radar reflectivity the observed rainfall will be classified into convective, stratiform and shallow precipitation types. The statistical characteristics of DSDs based on different ground-based disdrometers will be intercompared and analyzed. Based on the statistics of DSDs and radar reflectivity, the Z-R relationship will be constructed with respective to different season and different precipitation type. Finally rainfall estimation relationships using polarimetric radar measurements will be derived compared and discussed. An optimum radar QPE technique could be constructed in Taiwan. In the first year of this project, raindrop size distribution characteristics in summer season rainfall of two observational sites Taiwan and Palau in western Pacific are studied by using five years of impact type disdrometer data. The radar reflectivity rain rate relations of Taiwan and Palau have been investigated. The result had been published in J.G.R. SCI Journal.
