青藏高原东北边缘冰雹形成机理  

Mechanism of Hail Formation on the Northeast Border of Qinghai-Xizang Plateau and Its Neighbourhood

作　　者：康凤琴[1] 张强[1] 马胜萍 乔艳君 郭学良[4] 

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]兰州气象学校,甘肃兰州730021 [3]兰州市气象局,甘肃兰州730020 [4]中国科学院大气物理研究所,北京100029

出　　处：《高原气象》2004年第6期749-757,共9页Plateau Meteorology

基　　金：科技部社会公益研究专项"西北地区人工防雹消雹技术"项目(2002DIB10046);干旱气象科学研究基金项目"冰雹微物理过程的数值模拟研究"共同资助

摘　　要："穴道"理论认为,冰雹云中存在冰雹形成和增长的"穴道"。本文以在青藏高原东北边缘及毗邻地区常诱发冰雹灾害的东移短小切变线天气过程为研究背景,采用三维冰雹云分档模式,用MM5V3中尺度气象模式提供冰雹云模拟研究所需的环境大气状况,模拟研究了各类冰雹形成和增长的过程。结果表明,温度、云中上升气流、水平风速零线和云中各类水成物、各类冰雹质粒的空间分布满足"穴道"理论描述的配置区域是冰雹颗粒含水量的大值范围。同时显示出了小冰粒子(D<1mm)、霰和雹胚(1mm<D<5mm)、小冰雹(5mm<D<10mm),在冰雹颗粒形成初期,在-30～-50℃高空存在另外一个大值区域,两个大值区域中间有明显的分割,表明了两个区域形成的微物理机制不同,证明了冰雹云中的"穴道"是冰雹形成和增长的有效区域,因此"穴道"区域也是人工防雹消雹的主要区域。As a study backgroundof the shear wave moving eastward inducing hailstorm frequently on the northeastern border of Qinghai-Xizang Plateau and its neighbourhood, the formation and growth of hails are simulatedusing a 3D cloud model with hail-bin microphysics developed by Institute of Atmospheric Physics, Chinese Academy of Sciences and the large scale circulationsinformation obtained fromMM5V3 model. The results show that: 1the space distributionand positioningof temperature, the vertical airflow, the horizontal wind zero line region and 5 categories of hail and 5 hydrometeors meet the needs of the 'cave channels'(CC), the water contents of hail are large; 2thesmall ice particles(D<1 mm), graupel and hail embryos (1 mm<D<5 mm) and small hailstones (5 mm<D<10 mm) show another high water content region over -30～-50℃ altitudeat the initial stage of hail formation. Between them there is a clear low water content space, which means there are two different hail′s formation Mechanisms; 3as thehail and rainfall, the downwind is forming. On the region of cave channels, the downwind occurs too, here still is the center of high hail water content, even all upwind turn to downwind on the CC region. The simulated results present a detailedCC mechanism, even the downwind on CC region, reveal 'CC' in the hail cloud is effective region of formation and growth of hail.

关 键 词：冰雹云 青藏高原 冰雹灾害 微物理 上升气流 形成 MM5 区域 东北 效区 

分 类 号：P458[天文地球—大气科学及气象学] P426