金塔绿洲小气候效应的数值模拟

使用美国NCAR新版MM5V3．6非静力平衡模式，采用三重嵌套的降尺度方法，模拟研究了夏季金塔绿洲小气候效应特征。绿洲的存在改变了沙漠地区原有的环流结构和湿度分布；绿洲边界层低，沙漠边界层较高，绿洲较低的边界层结构实际上是一个保护层，使得绿洲大气中水分保存在较低边界层中，对绿洲生态系统的发展起到了保护作用；绿洲地区感热通量小，潜热通量大；沙漠地区感热通量大，潜热通量小。通过能量和水分的非均匀分布驱动了绿洲环流，使沙漠区域产生上升气流，绿洲区域产生下沉气流。

Numerical Simulation of Microclimate Effect in Jinta Oasis

Using the NCAR nonhydrostatic mesoscale model MM5V3. 6, triple nested technique and the NCEP reanalysed data in July, 2003, the microclimate effect in Jinta oasis was simulated. The main results show that the Oasis can change the circulation structure and humidity distribution of original desert area. The boundary layer height is lower in oasis and higher in desert and the structure of lower boundary layer is actual a protected layer, which make the atmospheric moisture of oasis to keep in the lower boundary layer and protected the oasis ecological system. Oasis has low sensible heat flux and high latent heat flux; but vice versa in desert. The inhomogeneous distribution of energy and moisture drives the oasis circulation, in which there is the downdraft over the oasis and the updraft over the desert.