西北地区一次沙尘天气的数值诊断分析  

Diagnosing Analysis of a Sand-Dust Event in Northwest China

作　　者：王川[1] 李韬[2] 侯建忠[1] 

机构地区：[1]陕西省气象台 [2]陕西省农业遥感信息中心,西安710015

出　　处：《气象科技》2008年第5期581-586,共6页Meteorological Science and Technology

摘　　要：利用实况资料和WRF模式预报场,对2006年4月9~11日西北地区一次大范围沙尘天气进行动力诊断及数值模拟分析。结果表明:此次过程属于蒙古冷槽型,地面强冷空气的爆发直接导致了沙尘天气的发生,沙尘发生在冷锋后及锋面过境时;高空急流的发展、移动对沙尘天气有预示作用;沙尘发生区次级环流在过程发展中有明显变化,下沉气流和上升气流并存;有利的散度场促进了上升及下沉运动的加强;涡度场的变化影响蒙古气旋,对沙尘天气的发生发展有指示意义;稳定的大气层结和近地层较大的垂直风切变是两个特征;WRF模式对此次沙尘天气有较好的模拟能力。A sand-dust weather event in Northwest China was diagnosed and analyzed by means of the routine observation data and WRF model outputs.The results show that this event belongs to Mongolia Cold Trough,and the main cause of the sand-dust event was the invasion of strong cold-air mass on surface,in which the sand-dust weather occurred at the rear of a ground cold front during the transit of the front.The development and movement of the upper-level jet was indicative of sand-dust weather.The vertical secondary ...

关 键 词：沙尘天气 数值模拟 急流 物理量场 

分 类 号：P425.55[天文地球—大气科学及气象学]