中国西南及其周边地区雷电活动的特征分析  

Characteristics of Lightning Activities Over Southwest and Its Circumjacent Areas in China

作　　者：周筠珺[1] 孙凌[1] 杨静[2] 胡初阳[3] 

机构地区：[1]成都信息工程学院大气科学学院,成都610225 [2]中国科学院大气物理研究所,北京100029 [3]西藏自治区气象局气象台,拉萨850000

出　　处：《高电压技术》2009年第6期1309-1315,共7页High Voltage Engineering

基　　金：中国科学院知识创新工程领域前沿项目(I AP09314);西藏强对流天气短时临近预报预警系统项目;四川省教育厅重点项目(2006A125)~~

摘　　要：为了进一步了解中国西南及其周边地区雷电的活动特征,利用搭载于卫星上的光学瞬变探测器(OTD)和闪电成像传感器(LIS)所取得的资料,通过不同尺度的时空分析,得到以下主要结果:由于西南及其周边地区气候、地形及下垫面性质差异较大,使得这一地区雷电的空间分布极不均匀,其中在青藏高原南侧分布得最多,其次是在青藏高原东部及东南部边缘和在四川盆地及邻近的城市群内也是雷电的多发区;雷电的年平均日变化特征在这些地区基本一致,但雷电数峰值出现的时段随纬度减小有逐渐后延的趋势;雷电主要发生于春夏季节,雷电的年际变化基本上为准3a的周期,且受ElNi灳o和LaNi灳a等气候异常事件的影响较大;雷电涛动响应指数(SOFI)可以较好地指示雷电的异常变化。ElNi灳o年雷电数距平在北纬31°以北、东经106°以西为负距平区域,其它的则为正距平区域;而LaNi灳a年雷电数距平特征则恰好与ElNi灳o年的相反。研究表明,OTD和LIS资料对于区域雷电气候分析有着重要的作用。In order to further comprehend characteristics of lightning activities over southwest and its circumjacent areas in China, temporal and spatial analyses in different scales were carried out by utilizing data of OTD （Optical Transient Detector） and LIS （Lightning Imaging Sensor） installed on satellites. Main results are as follows：Spatial distributions of lightning are rather uneven because of differences of climate, terrain, and underlying surface in these areas, in which south of Tibet plateau has the greatest lightning occurrence, east and southeast of the plateau, as well as Sichuan Basin and its adjacent cities also have higher occurrence. Annually average diurnal variations of lightning are generally consistent in all these areas, but peak time of lightning flashes is delayed as latitudes decreasing. In all these areas, lightning flashes mainly occur in spring and summer, and the interannual cycle of lightning flashes distinctly affected by El Nino and La Nifia is quasi 3-years. Southern Oscillation Flash Index （SOFI） can easily indicate exceptional change of lightning. Anomaly of lightning flashes in El Nino year is negative in areas where are north of 31 N and west of 106 E, while positive in the rest of areas. Characteristics of anomaly for lightning flashes in La Nina year are contrary to ones in El Nino year. It can be concluded that the data from OTD and LIS play a key role in the regional climatic analysis of lightning.

关 键 词：雷电活动 光学瞬变探测器 闪电成像传感器 监测 西南地区 时空分布 雷电涛动响应指数 

分 类 号：P427.32[天文地球—大气科学及气象学]