一次强沙尘暴过程中尺度平均动能变率诊断  

Total Kinetic Energy Budget of Mesoscale Condition in A Severe Dust Storm Process

作　　者：康凤琴[1] 李耀辉[1] 吕世华[2] 

机构地区：[1]中国气象局兰州干旱气象研究所甘肃省干旱气候变化与减灾重点实验室,甘肃兰州730020 [2]中国科学院寒区旱区环境与工程研究所,甘肃兰州730000

出　　处：《高原气象》2005年第2期204-211,共8页Plateau Meteorology

基　　金：科技部社会公益类项目"西北地区人工防雹消雹技术"(2002DIB10046);"西北沙尘暴预警;预测研究"的资助

摘　　要：利用MM5中尺度气象模式嵌套数值模拟的输出结果, 计算并分析了一次强沙尘暴天气过程的中尺度动能收支, 揭示了沙尘暴过程中的起沙、扬沙和输送的能量来源以及随高度的分布和演变过程。结果表明: (1)沙尘暴天气期间中尺度能量过程活跃; (2)沙尘暴过程因消耗局地动能而启动和发展, 能量来源在于高空的动能转化; (3)沙尘暴天气过程中, 非地转运动造成的气流穿越等压线运动是沙尘暴能量平衡过程中次重要的能汇项; (4)水平通量散度项为沙尘暴天气过程中主要的中尺度能汇; (5)垂直通量散度项为沙尘暴天气过程中的能源项。随着系统的演变, 能源中心从高层向中层转移, 直至后期的高层出现能汇; (6)摩擦消耗和次网格尺度效应以及计算误差R在沙尘暴天气过程中总体表现为能源项。The total kinetic energy budget is computed by the numerical simulative results of MM5 mesoscale meteorological model for studying the energy source and sink of severe dust storm in Northern China on 7~9 April 2001. The results show that (1) the mesoscale kinetic energy budget is very active. (2) the start up and development of the sandstorm system depends on depleting the local kinetic energy which comes from the high altitude. (3) the wind crosses contourresulting in local energy source throughout all sandstorm is the second important energy sink. (4)the horizontal flux divergenenceis the maximum energy sink. (5)the verticalflux divergent is the secondenergy source. As the system is developing, the center of energy source is moving from high to middle levels until the energy sink occurs at high level at the system′s vanishmentstage.(6) the friction depletion and sub-grid scale effect are the first energy source at total stage.

关 键 词：沙尘暴过程 中尺度气象模式MM5 中尺度动能收支 

分 类 号：P445.4[天文地球—大气科学及气象学]