近年来强沙尘暴天气气候特征的分析研究

Analysis of Climatological Characteristics of Severe Dust Storms in Recent Years in the Northern China

20 0 0～ 2 0 0 2年春季 (3～ 5月 )中国北方有 1 2次强沙尘暴天气过程发生 ,其中 1 1次与蒙古气旋有关。作者从干旱气候背景、环流状况、沙尘源、沙尘路径及天气系统等方面进行了分析 ,并集中对引发强沙尘暴的蒙古气旋进行了诊断分析。结果表明 :在这 3年中 ,春季我国北方强沙尘暴天气主要与蒙古气旋的发展移动有关 ,气旋冷锋后的大风是强沙尘暴天气发生的主要动力因子 ;蒙古国南部、巴丹吉林沙漠、腾格里沙漠、乌兰布和沙漠和毛乌素沙地是强沙尘暴过程的主要沙尘源地 ;影响我国的强沙尘暴的沙尘路径至少可分为 3种类型 ,即偏西路径、西北路径和南疆盆地型 ,以西北路径居多 ;我国北方春季的连续干旱、气温偏高及冷空气活跃是强沙尘暴天气形成的重要气候背景。

During the spring(March～May) of 2000～2002, twelve severe dust storms occurred in the northern China. There are eleven among them related with Mongolian Cyclone. This study was conducted in the aspects, such as, dry climatic background, circulation conditions, possible sand-dust sources, paths of sand transportation, and synoptic systems. The climate characteristics of the Mongolian Cyclone associated with severe dust storm has been diagnosed and analyzed. The results show that: In recent three years, the development of Mongolian Cyclones and the strong surface wind caused by the cold front induced the severe dust storm; The major sand-dust sources were in Gobi in South Mongolia, Badain Jaran Desert, Tengger Desert, Ulan Buh Desert and Mu Us Sandy Land; The paths of sand-dust that affecting the northern China can be divided into three types, at least: west, northwest, and southern Xinjiang basin. The northwest path is the majority; In the spring of 2000～2002, severe drought, higher temperature and active cold air over the northern China is the important climate background of formation and development the severe dust storm.