青藏高原对邻近地区天气系统影响的数值模拟研究  

Numerical Simulation of the Effect of the Tibetan Plateau on Weather System in the Neighborhood with LASG Mesoscale Model

作　　者：卿清涛[1] 钟晓平[1] 王春国[1] 

机构地区：[1]四川省气象局,成都610072

出　　处：《气象》2000年第1期19-24,共6页Meteorological Monthly

摘　　要：利用ＬＡＳＧη坐标有限区域数值预报模式，模拟了１９９８ 年４ 月２８ 日和８ 月１９日四川盆地的两次暴雨过程中高原地形高度变化对５００ｈＰａ和２００ｈＰａ 高度场、温度场和流场的影响。模拟结果表明：①高原地形高度的降低使本地的大尺度系统进一步加强，中小尺度的天气系统减弱或消失；②高原地形高度降低，本地温度升高，盆地的温度下降，而且春季的影响比夏季大得多；③高原地形对流场的影响与高度场相似，由于地形的“强迫”作用和背风坡气流的影响，流场变化最大的地方是高原东部和四川盆地西部，即地形高度骤变的地方。A numerical simulation on the effect of the Tibetan Plateau on weather systems in the neighborhood area was carried out by LASG η coordinate limited area mesoscale model (LASG MM).Two cases of heavy rain storms on April 28 and August 19,1998 were investigated under the topography with different relative heights.Study is mainly concentrated on the geopotential height fields,the temperature fields and streamline fields of 500hPa and 200hPa.Among the three kinds of fields,the temperature field suggests a large variation.When the relative height of the plateau is reduced,the temperature over the plateau goes up,and the temperature over the Sichuan Basin goes down.The magnitude of variation is larger in spring than that in summer.With lower relative heights,the large scale weather system over the plateau is strengthened,but the weather systems with middle or small scale are weakened over the plateau.On the other hand,the geopotential heights is reduced and the weather systems with small scale are strengthened over Sichuan Basin.Effect of the plateau with different relative heights on the streamline fields is similar to that of the goepotential field.With the influence of the forced wave and the lee wave,the streamline fields suggest the largest variation over the intersection area of the plateau and basin,which is exactly where the relative height changes most greatly.

关 键 词：地形影响 天气系统 Η坐标 数值模拟 青藏高原 

分 类 号：P44[天文地球—大气科学及气象学] P435