臺灣屬於海島型國家，在眾多研究中顯示，臺灣各地的污染物濃度分布、降水時機強度會受到海陸風的影響。海陸風亦和更大尺度的環境風場耦合，影響降水時空分布。然而現有的海陸風相關研究多以地面測站或是模式模擬，較少提及大氣垂直觀測結構，故本計畫希望藉由近年新興之無人機大氣觀測技術，提供相較於探空氣球更高的時間與垂直空間解析度之觀測，且具有豐富多元的儀器酬載能力的優勢，並加上地面測站之觀測結果、氣象局探空氣球之施放、環保署空氣品質監測站資料，多方面探討弱綜觀天氣條件下，南部地區典型海陸風垂直結構日夜變化及三維局地環流特徵，期望做為未來天氣守視的重點和氣象預報之參考。 在具體工作規劃上，本計畫提出前期由地面觀測資料、再分析場與模式等資料初步建構南部地區海陸風之特徵，並作為弱綜觀密集觀測策略擬定之依據；密集觀測期間，選定台南地區自近海、平原至近山區三測點，進行無人機同步及日夜連續觀測，建構時序性海陸風剖面；最後透過整合資料分析，結合無人機觀測、探空氣球觀測與其他地面測站觀測資料，針對密集觀測個案進行探討，完整描述弱綜觀天氣條件下，局地環流與海陸風特徵，及對於空氣品質與降水的潛在影響。第二年的工作將延續第一年的成果，持續精進改良觀測策略，並執行一次密集觀測實驗，整合兩次密集觀測成果，統整提出臺灣南部弱綜觀海陸風的特徵與對於空氣品質與降雨的影響。 ;Many researches showed that the distribution of air pollution and the timing, strength of precipitation would be affected by land-sea breeze in Taiwan. Land-sea breeze would affect the distribution of precipitation coupling with large-scale environmental wind. Most of studies of land-sea breeze were based on the results from model simulation, on the other hand, the observation evidences are limited. Therefore, to resolve the vertical structure of atmosphere by using Unmanned Aircraft System (UAS) might be a new direction. Advantages of UAS include a higher payload and higher spatial-temporal resolution as compared with traditional sounding balloons. The proposed project will use UAS to observe atmospheric profile and study the typical diurnal change of land-sea breeze under weak synoptic weather condition in southern Taiwan. The new strategy of UAV observation is hoping to be a consultation of weather monitoring and weather forecast in the future. For the detailed proposal, first of all, our team are going to analyze historical observation data, reanalysis data, and modeling data to examine the features of land-sea breeze over southern Taiwan, and make a better observing strategies according to the features. Three spots synchronous day-night UAV observations will be carried over Tainan during intensive observing periods. By integration analysis of UAV, sounding balloon, and ground station observation data, we can get the whole picture of the land-sea breeze over southern Taiwan under weak-synoptic weather condition. Our team will improve observing strategies continuously, and perform another IOP in 2022 based on the experience in 2021. Finally, we would like to characterize the features of the land-sea breeze under weak-synoptic weather condition, and to summarize its impacts on regional air quality and precipitation.
