宁夏雷暴天气过程划分及环流分型和环境场特征  

Classification of Thunderstorm Processes with the Circumfluence Types and Environmental Field Characteristics in Ningxia

作　　者：纪晓玲[1,2,3] 王式功[3] 穆建华[1] 陈晓娟[1] 杨侃[1] 辛尧胜[1] 

机构地区：[1]宁夏气象防灾减灾重点实验室,银川750002 [2]中国气象科学研究院灾害天气国家重点实验室,北京100081 [3]兰州大学大气科学学院,兰州730000

出　　处：《应用气象学报》2010年第3期329-334,共6页Journal of Applied Meteorological Science

基　　金：中国气象局新技术推广项目(CMATG2008Y11);宁夏自然科学基金项目(NZ07125)共同资助

摘　　要：利用1961—2005年宁夏25个气象站雷暴观测资料,根据雷暴发生特点对雷暴天气过程进行划分,得到全区(大部)性、区域性Ⅰ、区域性Ⅱ、持续性、局部性、分散性6类雷暴天气过程;并利用1996—2005年NCEP/NCAR逐日全球再分析资料,对10年来5—9月263例区域性雷暴天气过程进行分析,总结得到有利于宁夏雷暴天气发生的主要环流分型有4类:蒙古冷涡(槽)型、东北冷涡后部横槽型、河套低涡型、西风槽型。其中,前3种类型下易出现持续性雷暴天气过程。易于发生雷暴的环境场特征为宁夏处于500 hPa"西高东低"环流形势下的(弱)西北气流中,地面一般为气旋或热倒槽所控制,蒙古国至我国新疆一带或河西一带有冷锋、切变东移南下,中低层有一定的水汽和辐合抬升条件。Using the thunderstorm observation data of 25 weather stations in Ningxia during 1961—2005,according to the distribution of weather stations and occurring characteristics of thunderstorms,6 thunderstorm types are defined as thunderstorm process over whole or most of Ningxia,regional thunderstorm processⅠandⅡ,continuous thunderstorms process,local thunderstorm process and dispersed thunderstorm process.Statistics derives that during 1961—2005,there are 110 thunderstorm processes over whole or most of Ningxia,occupying 3%of the total thunderstorm processes,and 357 regionalⅠthunderstorm processes,occupying 9.2%,931 regionalⅡthunderstorm processes,occupying 23.9%,1039 local thunderstorm processes,occupying 26.7%,1461 dispersed thunderstorm processes,occupying 37.5%,and 27 continuous thunderstorm processes. 263 regional thunderstorm processes occurred from March to September during 1996—2005 are analyzed using the NCEP/NCAR global reanalyzed data,indicating that there are 4 main circulation types favorable for the occurrence of thunderstorms in Ningxia：Mongolia cold vortex,cold transversal trough at the back of northeast cold vortex,Hetao cold vortex and west cold trough.The first 3 circulation conditions often lead to continuous thunderstorm.Several types of environmental field are favorable for the occurrence of thunderstorms in Ningxia,for example,weak northwest airflow under the circulation background of high in the east and low in the west at 500 hPa,ground surface air being controlled by cyclone or warm inverted trough,cold front,shear moving eastward and southward from Mongolia and Xinjiang or west Hetao,certain moisture and convergence uplifting conditions in the mid-low level,and the relative humidity reaching 50%—80%at 700 hPa. From March to September,if the 4 circulation types and the environmental characteristics mentioned above occur in the area from Europe to Asia,then attentions should be paid to the possibility of thunderstorms. The relationships between circulation background and

关 键 词：宁夏 雷暴天气过程 划分标准 环流分型 环境场特征 

分 类 号：P446[天文地球—大气科学及气象学]