【摘要】 采用对数压力坐标系的大气热力、动力方程组,分析了由于城市的加热和摩擦作用,在大气层结不稳定情况下的热岛环流,给出了表征热岛基本特征的垂直运动,水平运动和温度场的空间结构,从理论上证实了热岛环流在不稳定城市边界层中存在的可能性,并得出了如下主要结论:(1)垂直运动在市区是上升运动,在郊区是下沉运动,在低层 z=150m 处有一闭合中心;(2)流场在市区上空呈一层波动,波谷在上风区,波峰在下风区,波长为城市半宽的4倍;(3)地面的高温区出现在城市的下风区,且无逆温层出现。更多还原

【Abstract】 The heat island circulation induced in unstable stratification is investigated by using thermo-dynamic and dynamic equations of atmosphere in log—pressure coordinate.The basic features ofheat island such as spatial structure of vertical motion,horizontal motion and temperature are giv-en.The results testify in theory the possibility that heat island circulation also occurs in unstableurban boundary layer.The results show that(1)ascending motion is in the urban,sinking motionin the suburbs,a closed center in the lower layer(z=150m),(2)the flow field appears to be awave over the urban,the wave length is four times of the half width of city,(3)the high tempera-ture zone is in the downwind of the urban,and there is no any inversion layer.更多还原