摘要
利用ARPS(Advanced Regional Predictional System)中尺度数值模式,对2007年7月19日低涡天气背景下发生在祁连山区的一次比较典型的地形云降水过程中云和降水的宏微观结构特征进行了深入的模拟研究和分析。结果表明,ARPS模式能够较好地模拟出地面降水分布及其发展演变特征;祁连山北坡陡峭地形的抬升作用是祁连山云系降水的主要动力机制;祁连山地形作用下云和降水的微物理结构随云的不同发展阶段呈现出不同的特征。
A case of heavy rainfall in the Qilian Mountains on 19 July 2007 was simulated using the mesoscale numerical model ARPS（Advanced regional prediction system）.The simulated rain band was basically consistent with the observations.The macrophysics and microphysics structure characteristics of the cloud and precipitation of the heavy precipitation process were mainly discussed.Results show that under the influence of the Qilian Moutains,the horizontal distribution features of the hydrometeor in the cloud system were as follows： in the early stage,the content of all hydrometeor was little and homogeneous,and in the initial stage of development,due to the intrusion of lower cold air in northwest,the content of cloud water,cloud ice,snow,graupel（hail） and rain water began to increase and became less homogeneous;in the development and prosperity period,along with the emergence of the lower shear line and vortex center on the north side of the Qilian Mountains,the content of all hydromeror in horizontal direction increased significantly and vertical thickness extended obviously;with a gradual eastward shift of cloud system,the scope of the hydrometeor became narrow and its content decreased.The vertical distribution features of the hydrometeor in the orographic cloud were as follows： in the early stage,cloud water mainly distributed in the lower layer and graupel mainly in the freezing level,ice water mainly in the middle and upper level,rain water mainly in the warm zone of lower part close to the ground in the cloud;in the initial stage of development,as a result of enhanced vertical motion,the content of the different hydrometeor increased;in the heavy rainfall period,from the ground to the top level,the content of cloud water,ice,snow and graupel（hail） had the highest value;in the weakened period,the content of all hydrometeor decreased significantly and even disappear.
出处
《干旱气象》
2013年第1期18-23,共6页
Journal of Arid Meteorology
基金
国家自然科学基金重点项目"西北地区地形云结构和降水机理研究"(40533015)
国家科技支撑计划课题"混合云人工增雨技术研究"(2006BAC12B02)
江西省气象局面上项目"江西空中云水资源开发潜力"共同资助
关键词
祁连山
地形云
数值模拟
the Qilian Mountains
orographic clouds
numerical simulation
