此計畫主要研究目的為藉由高解析度氣象模擬，探討臺灣綜觀環境風場、局部環流結構與複雜山區環境之間交互作用下，背風面渦旋系統的結構特性。分析方向包含：(1) 地表加熱作用對大氣熱、動力過程演變的影響; (2)綜觀環境場較弱的大氣條件下，臺灣處於較為穩定的大氣條件，釐清背風渦旋結構特性; (3)探討局部環流結構、綜觀尺度風場以及與地形的交互作用，對背風渦旋系統的影響; (4) 探討地表水文循環過程對臺灣地區邊界層模擬的影響。研究方法，挑選適合個案，使用WRF氣象模式，進行高解析度氣象模擬。為因應高解析度氣象模擬，在地形的處理，使用了90-m解析度Shuttle Radar Topography Mission (SRTM)衛星資料。而在地表水循環過程的探討，使用Noah-MP (multi-parameterization options) 地表水文模式，討論地表水循環變化過程。由於Noah-MP地表模式考量了較複雜的地表水文循環過程，包含動態的地下水位變化(dynamically determined water table)以及側向水的排水過程(lateral flow)，這對臺灣複雜山區地形之地表水循環過程相當重要。且當模式模擬進入更高解析度時，台灣山高坡陡所形成的地下水傳送過程的模擬也顯得更為重要。預期此研究成果，將可提供在複雜山區環境，大氣熱、動力過程的發展機制，同時釐清臺灣地區綜觀尺度風場、環境局部風場以及複雜地形之間的交互作用，以及其對背風渦漩形成的影響。 ;The objective of the proposal is to utilize the high resolution meteorological model to investigate the interaction among the synoptic wind flow, local wind flow and the complex terrain, and its effect on the formations of the leeside wake/vortex/flow. The analysis will focus on: (1) Under the weak synoptic forcing, investigate the dynamic/thermodynamic characteristics of the local wind circulation; (2) Under the stable stratified atmospheric conditions, study the characteristic of the leeside wake/vortex/flow; (3) Study the interaction between the synoptic wind flow and the local air flow, and study its subsequent effect on the leeside flow; (4) Examine the land surface hydrologic processes including the soil moisture variation and surface/subsurface runoff processes on the planetary boundary layer development. In this study, we will first select the appropriate case and utilize the high resolution Weather Research and Forecasting (WRF) model to study the fine scale structures over the mountainous area. We will also adopt the 90-m resolution Shuttle Radar Topography Mission (SRTM) satellite data to provide the terrain height. To study the land surface hydrologic processes, we will utilize Noah-MP (multi-parameterization options) land surface model (LSM). Unlike Noah LSM that only considers a free drainage lower boundary condition, the Noah-MP LSM considers the dynamically determined water table depth within the model soil layers and the lateral flow of the aquifer water, those processes are generally important over the complex terrain and on high- resolution model.We are expecting the results from this study should be able to provide a comprehensive understanding of the development of the atmospheric dynamic/thermodynamic processes over the complex topography, and to figure out the formation mechanisms of the leeside wake/vortex/flow structures. The interaction between the atmospheric planetary boundary layer the land surface hydrologic processes will be discussed through the fine scale meteorological and land surface hydrologic modeling technique.
