干谷和湿谷边界层气候差异的数值模拟研究

A STMULATION OF CLIMATIC DIFFERENCES BETWEFN DRY VALLEY AND RIVER VALLEY

本文建立了一个采用地形坐标的、包含大气边界层湍流参数化方案,大气辐射过程的参数化方案、陆-气-水相互作用的地面温湿度预报方案等物理过程的非静力近似中小尺度数值模式,用这个模式试验研究了在气候平均值的背景下谷底水体的有无对山地气候影响的一般情况。模拟结果表明:由于水体的存在,夜间谷底气温较干符情况有较大的升高,山谷逆温受到破坏;白天谷底气温则有降低。湿谷中的地湿一般都较干谷中大,尤其是夜间更为明显。无论白天还是夜间,由于山谷风和湖陆风共同作用的结果,湿谷中的风速都此干谷中大,湿谷中的局地环流比干谷中的更为明显。

In this paper,a two-dimensional non-hydrostatic numerical model is deve-loped.. Using this model, we examine the climatic differences between river valley and dry valley under general background of the averaged climatic condition over a typical mountainous region on 30°N in China.The results show that the waterbody may make air temperature in valley increase at night and decrease in the daytime, air specific humidity increase, esp.t night.Due to the joint action of mountainvalley breezes and land-lake breezes, the wind speed over river valley is always larger than that over dry valley, the local circulations over river valley are more obvious than that over dry valley.This study also shows that the numerical simulation method is effctive in the study of climatic resources in mountainous regiont