• 作者： 黃清勇
• 作者服務機構： 中央大學大氣科學系
• 中文摘要： 本文探討瞬問污染源於沿岸鋒生情況下平流與擴散的過程。研究方式為使用一中尺度邊界層數值模式，此模式包含亂流閉合及雲微物理。系統性模擬實驗結果顯示，於鋒面變形期間，雲及污染物之分佈對環境風速、垂直濕度剖面與風切，以及附近地形障礙之高度與位置之變化皆相當敏感。本文詳細探討這些因子的作用，發現於此沿岸風場及穩定度多變情況下，污染物的平流與擴散過程相當複雜。本文亦探討亂流擴散與平均氣流傳送之相對重要性，特別針對污染源之高度與釋放時間。
• 英文摘要： Advection-diffusion processes of presumptive instantaneous pollutant sources are investigated forcoastal environmental conditions where frontogenesis appears in response to differential heating. Theinvestigation relies on a mesoscale planetary-boundary-layer (PBL) numerical model which includes themodified E-εturbulence closure and cloud microphysics for resolving turbulence activities within the PBLand clouds. Model results from control numerical experiments show that the cloud and pollutant dis-tributions during the frontal formation and flow deformation are sensitive to variations in ambient windspeed, vertical moisture profile and wind shear, and the height and location of the neighboring terrainbarrier. The effects due to these factors are discussed in detail in this study. It is found that the advection-diffusion processes of the pollutants are rather complicated in coastal varying wind and stability conditions.The relative importance of turbulent diffusion and mean transport is also discussed with relevance to thesource height and emission time.
• 中文關鍵字： advection-diffusion; PBL; frontal formation
• 英文關鍵字： --