冰雹云垂直累积含水量密度与降雹大小的关系研究  

Correlation Between the Vertically Integrated Water Content Density of Hail Cloud and the Hail Diameter on the Ground

作　　者：刘治国[1] 田守利 邵亮 宋秀玲[1] 魏文娟[4] 伏晓红[1] 

机构地区：[1]兰州中心气象台 [2]重庆市巴南区气象局,重庆401320 [3]甘肃省兰州市气象局,甘肃兰州730020 [4]甘肃省气象局,甘肃兰州730020

出　　处：《干旱气象》2008年第3期22-28,共7页Journal of Arid Meteorology

基　　金：中国气象局新技术推广项目"青藏高原东北侧局地冰雹短时临近预警技术"(CMATG2008Y02);"西北地区人工防雹消雹技术推广应用"(CMATG2007Z08);甘肃省气象局重点项目"基于新一代天气雷达和LD-Ⅱ雷电定位仪的省市雷电监测预警方法和系统研究"(2007-18)共同资助

摘　　要：垂直累积含水量（Vertically Integrated Water Content，简称：VIWC）包括单位底面积的垂直柱体内固态和液态水质量的总和，是以3D—Barnes方案插值的新一代天气雷达反射率因子等高平面资料，假定固态和液态水滴反射得到的反射率因子都满足由液态水滴引起的经验导出关系，将垂直积分改为离散求和的方式进行计算的。利用VIWC与云体高度之比计算垂直累积含水量密度（Vertically Integrated Water Content Density，简称：VIWCD），用MAX函数逐个提取冰雹云在降雹时段内的最大VIWCD（简称；VIWCDmax），采用统计和回归处理技术，对2004—2006年兰州新一代天气雷达监测到的54例冰雹云在降雹时段内VIWCDmax与地面最大降雹直径之间的关系进行了分析。结果表明：最大冰雹直径相同的冰雹云内部雹胚竞食成雹粒的数密度在降雹时段内基本相当，雹粒尺度是影响雷达反射率因子的重要因素，它决定了冰雹云的雷达回波强度和地面降雹的大小；冰雹云VIWCDmax与地面最大降雹直径之间存在函数式（6）的关系；冰雹云倾斜结构和雷达扫描模式是影响（6）式效果的2个重要因素。Based on the reflectivity factor of CINRAD （ the constant altitude plan data） interpolated with 3D - Barnes scheme assuming that the reflectivity factor of solid water drop would accord with the experiential relation of the reflectivity factor induced by the liquid water drop, Vertically Integrated Water Content （VIWC） including solid and liquid water was calculated with the method of discrete sum instead of vertical integral. The ratio of VIWC and the upright height of hail cloud is defined as Vertically Integrated Water Content Density（ VIWCD）, the maximum VIWCD （shortened form： VIWCDmax） is identified by use of MAX function. With methods of statistic and regression equation, the correlation between the VIWCDmax of hail cloud during hailing process and the maximum hail diameter on the ground is analyzed in detail for 54 hail clouds observed by Lanzhou CINRAD during 2004 -2006. Results show that the magnitude about number density of hail pellet coming from hail embryo in hail clouds with the same maximum diameter is equivalent during hailing process, and hail pellet scale is an important factor which determined hail cloud echo intensity and hail size on the ground ; the piecewise function （6） which is affected by two important factors of hail cloud tilted structure and radar scan model reflects the correlation between the VIWCDmax of hail cloud during hailing process and the maximum hail diameter.

关 键 词：垂直累积含水量密度 冰雹直径 关系 

分 类 号：P412.25[天文地球—大气科学及气象学]