雲雨系統內二氧化硫的輸送及去除之數值研究

A Numerical Study of Transport and Removal of Sulfur Dioxide in Cloud System

王建國(Chien-Kuo Wang) ； 陳景森(Ching-Sen Chen)

《大氣科學》 12卷1期 (1985/03) Pp. 103-126

摘要

本文企圖利用二度空間的對流性雲雨模式和一個包含平流、擴散、產生以及去除項的SO2連續方程式，來探討相對於雲雨區，有不同位置及分布的SO2，在雲雨系統發展過程中，其內、外環流對於SO2的輸送和去除有何影響。關於去除項的參數化，採用與Fisher（1982）類似的方法來處理。而SO2連續方程式中的平流項之數值方法，則選用Shir和Shieh（1975）所發展出來解正值平流項的數值方法。在這個數值實驗中，將以兩種在動力結構上不盡相同的對流性雲雨系統，來討論SO2的輸送和去除情形。其一為存在於環境垂直風切較強的雲雨系統（近地面的風速較大），另一則存在於環境垂直風切較弱的雲雨系統。結果顯示此兩者對於SO2的輸送和去除有很大的差異。另外，吾人尚考慮SO2從下邊界擴散至地面的情形，發現它對SO2在雲雨內的輸送和去除情形影響不大。

並列摘要

An attempt to study the effect of cloud dynamic on the transport and removal of SO2 by cloud-water and rain-water is made by coupling a two-dimensional cloud model with a continuity equation of SO2. We employ a positive definite finite difference method developed by Shir and Shieh (1975) to solve the advection term of SO2. The parameterization of the removal of SO2 by cloud and rain is similar to that of Fisher (1982).Two different types of cloud system were examined in this simulation study. One had large vertical shear of horizontal wind in the low layer and the other had small one. Large difference about the depletion of SO2 from cloud and rain system was attributed to the internal dynamic structure of cloud system, the relative position of the initial distribution of SO2 with respective to cloud system, and the transport of SO2 due to ambient wind.