利用闪电定位、天气雷达和大气探空等多源资料,结合海南岛西北部7个区域的自动气象站资料,对2020年在海南岛西北部首次出现的两次雷暴天气过程(2020-02-13-2020-02-14)进行了综合分析,同时对雷暴形成的大气环境要素特征进行了统计.结果表明:两次雷暴所对应的地闪活动和回波强度存在一定的差异,第二次雷暴过程的平均地闪频数和不同阶段的回波强度都较第一次大,但第一次雷暴的正地闪比例较高,达到了46％,第二次雷暴对应的正地闪则只占9％.通过对2月份温度和湿度的日变化统计发现,雷暴活动期间的气温整体要高于晴天和阴雨天的气温,午后气温的增温趋势也更为明显;而在14:00时之前,其相对湿度也是整体高于晴天和阴雨天的相对湿度.探空资料的结果显示,对流有效位能、云底高度以及中层平均相对湿度都可作为指示对流活动的指标,但中层平均相对湿度更为合理.

采用2010～2018年海南岛天气分型资料和闪电定位数据,统计分析在南海低压槽影响下海南岛地闪发生概率和地闪频次的时空分布特征.结果显示:4～10月南海低压槽是影响海南岛天数最多的天气分型,产生的地闪频次仅于华南沿海槽,列第二位;南海低压槽影响的月份主要为5～10月份,地闪频次以8月最多,5和10月较少;海南岛地闪发生概率和地闪频次时段分布曲线均呈单峰特征,高值区分布在12:00～21:00时段,15:00～18:00时段为高峰期,在12:00～21:00时段过程中后2 d的地闪发生概率要比过程中前2 d的稍高,但地闪频次要明显低于过程中前2 d;海南岛地闪发生概率月分布曲线呈单峰特征,8月份地闪发生概率最高,5和10月相对较低;海南岛21:00～次日12:00时段地闪发生概率高值区主要分布在东南沿海并随时间逐渐向西北扩展,概率值在5％以下,12:00～21:00时段地闪发生概率高值中心主要分布在昌江、白沙、儋州等海南岛西部市县,15:00～18:00时段概率中心值达40％.

采用2010-2019年4～10月海南岛闪电定位数据和相关天气分型资料,对海南岛正地闪的频次和频次占比的年分布、月分布、时分布以及各天气分型影响下时分布的特征进行了分析,结果发现:海南岛4～10月的正地闪占比为4.60％,各年份的总地闪频次、正地闪频次、正地闪占比基本呈正相关关系;4～10月的正地闪频次曲线和总地闪频次曲线同为双峰型,且两条曲线峰值所对应的月份相同,但总地闪频次曲线以5月为主峰、8月为次峰,而正地闪频次曲线则以8月为主峰、5月为次峰,8、9月份的正地闪占比要高于其他月份;当采用整体累加法来分析正地闪的时分布时,正地闪频次曲线和总地闪频次曲线同为单峰型,且两条曲线峰值所对应的时间相同,峰值均出现在16:00～17:00,13:00～19:00正地闪占比呈逐时上升趋势;当采用雷暴过程总地闪频次峰期固定法来分析正地闪时分布时,正地闪频次峰值与总地闪频次峰值所对应的时次一致,高峰期前后2小时内的正地闪占比整体呈上升趋势,在总闪频次峰值期稍有下降,正闪主要发生在总闪频次的高峰期及之后,而负闪主要发生在总闪频次的高峰期及之前.通过对海南岛13:00～19:00三种天气分型的正/负地闪密度空间分布特征的分析,发现三种天气分型的正地闪密度高值区相对于负地闪密度高值区稍偏雷暴移动的下游位置.通过分析三起由正地闪所引起的雷灾个例,其结果显示,正闪引起的雷灾可以出现在雷暴过程的成熟期或消亡期,甚至在层状云条件下也可发生,且雷电流强度大、破坏性强.

采用2010—2018年的海南岛天气分型资料和闪电定位数据,统计分析海南岛在西南低压槽影响下地闪发生概率的时空分布特征,结果显示:在西南低压槽天气影响下,海南岛地闪主要出现在4—9月;地闪发生概率月分布曲线呈双峰特性,以8月为主峰、5月为次峰,00—12时(北京时,下同)的地闪发生概率月分布曲线与全天不同,呈逐月上升特征;地闪发生概率和地闪次数时段分布曲线呈单峰特性,峰值均出现在15—18时,除12—21时外其他时段的地闪发生概率和地闪次数都很低,控制过程的后期比前期的闪发生概率和地闪次数略高;00—12时各时段海南岛地闪发生概率中心分布在东南沿海,概率中心值在5％以下,12—21时各时段地闪发生概率中心分布在北部内陆,概率中心由白沙中部向澄迈东部移动,移向呈西南—东北向,15—18时概率中心在澄迈南部达到最大值40％,21时以后概率中心分布在屯昌境内,中心值在5％以下;7—9月各时段的地闪发生概率均比4—6月高,但地闪次数峰值比4—6月少,两者各时段的地闪发生概率的空间分布完全一致.

采用2014-2018年6-8月海口多普勒雷达、闪电定位、海南省天气分型等数据资料,分析海南岛分别在西南低压槽、南海低压槽、华南沿海槽影响下40 dBZ回波伸展到0℃层高度的概率,0℃层上强度≥40 dBZ的回波面积,地闪次数与0℃层上强度≥40 dBZ的回波面积比值,地闪次数及地闪发生概率等变量的时空分布特征,结果表明:(1)0℃层上强度≥40 dBZ的回波面积与地闪次数呈正相关.(2)午后40 dBZ回波伸展到0℃层高度的概率与地闪发生概率呈正相关.(3)午后40 dBZ回波伸展到0℃层高度的概率中心与地闪发生概率中心完全重合.(4)在华南沿海槽影响下,0℃层上强度≥40 dBZ的回波面积最大,同时地闪次数最多,午后地闪发生概率中心分布在以海口市南部为中心的海南岛东北部内陆.(5)在南海低压槽影响下,40 dBZ回波伸展到0℃层高度的概率最高,同时午后地闪发生概率最高,午后地闪发生概率中心分布在以儋州市南部为中心的海南岛西北部内陆.(6)在西南低压槽影响下,午后40 dBZ回波伸展到0℃层高度的概率、0℃层上强度≥40 dBZ的回波面积、地闪发生概率、地闪次数等指标在3种天气分型中最低,午后地闪发生概率中心分布在以澄迈县南部为中心的海南岛北部内陆.

The World Wide Lightning Location Network (WWLLN) data was used to analyze the lightning activities of Tropical Storm Bebinca (2013) and Super Typhoon Rammasun (2014). The relationships between lightning activity and cyclonic intensity change, direction of storm motion of the two tropical cyclones were also investigated. Preliminary analyses showed that the two systems produced a large number of lightning strokes in the region of $0\sim800\ km$ from the centers, the numbers are 111,289 and 125,046 for Bebinca and Rammasun, and the average lightning stroke rate of Bebinca was 1021 str/h and that of Rammasun was 680 str/h. Both for Bebinca and Rammasun, their lightning frequency were oscillating in the whole lives, however, it was varied little for Rammasun and decreased for Bebinca. The radial and spatial distribution of lightning showed that the lightning of Bebinca mainly appeared at rain band outside of 300 km and most of lightning occurred at the west of cyclone. For Rammasun, lightning mainly produced in the regions of 160 km away from center, including the inner rainband and outer rainband, and mainly centralized in the west of cyclone. When the area around each storm was divided into four quadrants with respect to storm motion, right and left front, and right and left rear, the maximum number of flashes occurred in the left-rear quadrant of Bebinca, while in the right-front and left-front quadrant of Rammasun. The relationship between lightning frequency and intensity change for Bebinca was weak, while strong for Rammasun. The moving directions of Bebinca and Rammasun exhibited a weak relationship with lightning frequency, but well correlated with lightning spatial distribution.

A balloon-borne sounding system was designed to measure the vertical electric field, humidity, temperature and precipitation particle (size and type of ice phase) within thunderstorm. Based on the principle of GPS tracking, a ground-based automatic tracking and transceiver system (hereinafter referred to as the ground system) was designed to receive all signals transmitted from the sounding continuously. Some results obtained by this system had been introduced in this paper. A result of a sounding measurement in Aug.22 2016 in the inland plateau of China shows that total four charge regions were found in the mature stage of a thunderstorm and charge polarity was alternate in a vertical direction with a negative charge region at the lowest in the warm cloud region. Another result of a sounding measurement in Aug.26 2018, obtained above the tropical island of China, shows that at the dissipation stage of the thunderstorm, there is a positive polar charge zone in the warm cloud, while there is a strong negative charge zone near 0\square level and a positive charge zone above. This system could adapt to different environments and obtain valid data of electric field (E). However, in actual observation, there was still some shortness in obtaining the information of ice phase particles image.

利用海南省气象局在海南岛内布设的地闪定位网、海口地区组网大气平均电场仪及雷达对超强台风“威马逊”过程的监测资料,分析了该过程在海南岛过境(2014年18日12时至19日12时)时陆地及附近海域的地闪活动的时空分布特征.闪电监测结果显示,18日18时起,发生的地闪数目开始增多,至18日22时达到顶峰,至19日8时以前仍保持较强的频数.地电主要发生在东方市境内及近海,最大密度值出现于洋面,达到了4.7次/km2(海面),陆地最大地闪密度为1.6次/km2.通过对地面电场的演变特征分析来看,嵌于台风外围雨带里的对流云具有三极性电荷结构特征,这与大部分常规夏季雷暴云具有一致性.

Analysis of soil resistivity in Haikou City for nearly one year, the soil moisture data, and the meteorological data information provided by automatic meteorological station, the results show that soil resistivity of Haikou shows the distribution features of the east side lower than the west; soil resistivity of volcanic ash soil changes in inverse u-shaped curve with the seasons, while the red soil and sand soil resistivity changes with the seasons in u-shaped curve, and soil resistivity of the volcanic ash is not reduced due to the rainy season, instead it increases; soil resistivity of volcanic ash rises with the increase of soil humidity, while the soil resistivity of red soil and sand soil decreases with the increase of soil humidity. The soil resistivity of volcanic ash and red soil decreases with the increase of soil temperature, while the soil resistivity of sand soil rises with the increase of soil temperature. The soil resistivity of volcanic ash and red soil rises with precipitation, while soil resistivity of sand and red soil rises with precipitation. The decline of red soil was most pronounced.

利用海南省地闪定位网获取的4年(2010年1月至2013年12月)地闪定位资料,详细分析海南岛地闪活动的时空分布特征,结果显示,海南岛的地闪活动主要发生在4-10月;呈双峰特征,峰值分别出现于5月和8月,分别约占全年总地闪数的23％和18％;地闪活动在6-7月明显地间歇性减少.从日变化特征来看,地闪在14:00-20:00时段最为频繁.16:00左右达到峰值,而5:00左右有一个较弱的峰值,2个峰值所占比例分别约为11.3％和4.2％.通过对比分析各地区的地闪活动,发现日变化呈现双峰特征的区域主要集中在东、南和西部沿海地区,而中部内陆及靠近琼州海峡的北部沿海地区呈单峰值特征.海南岛中部内陆山区的地闪密度大,沿海地区地闪密度小,并且存在2个地闪密度高值区.

Based on the cloud-to-ground (CG) flashes data from 2010 to 2013 obtained- by the VLF lightning locating networks in Hainan Province, the temporal and spatial characteristics of cloud-to-ground (CG) flashes activities were analyzed. The results indicated that more than 99% of CG flashes occurred between April and October and two peaks of CG activity appeared in May (23%) and August (30%).The CG flashes occur clearly with a characteristic of daily and monthly variation, in which there are two peaks. The peaks of daily variation occur at 5:00 am and 16:00 (Beijing time) almost. In terms of areas, the CG activities in the most coastal areas present the changing characteristic of double peaks. However, there is only a single peak in the inland areas and the northern coastal areas near the Qingzhou Strait. The first peak (the early peak) occur between 2:00 and 7:00 am, and the second one (the late peak) occur during the period from 12:00 to 17:00, where the CG activities present the double-peak characteristic. The spatial distribution of CG flashes presents certain regularity that the CG flashes density is the largest in the inland mountainous areas and the density becomes more and more small as the spatial position further outspread forward the coastal areas. In addition, there are two high value centers of the CG flashes density, and the spatial distribution of flashes density exist differences at different times especially in the south of Hainan Island and on the north of Wuzhishan mountain.

Vehicle-mounted X-band dual-polarization radar, located at coastal region (118.9 E, 25.1 N) in Fujian province, almost completely captured the entire life span of a local severe thunderstorm on August 28, 2009. Combine the radar strong echo volume and hydrometers retrieved by hydrometer identification (HID) algorithm, the characteristics of cloud-to­ ground (CG) flash in different stage of thunderstorm were analyzed. The study case experienced several stages and developed into a squall line in its mature stage with a maximum CG rate of 85fl/5min. CGs mainly occurred in the convective region and CG rates per 5 minutes had a linear positive correlation with strong echo volume in convective region. Seven types hydrometers was identified by HID, and five types of dominant hydrometers were found in thunderstorm, they are rain, aggregates, low-density graupel, high-density graupel, and vertical ice. The spatial distribution of hydrometers showed that rain mainly located at lower portion of thunderstorm warmer than O'C, high-density graupel at middle, low-density graupel and vertical ice at upper portion. CG rates were also positively correlated with the samples of dominant ice phase hydrometers in convective region. Keywords-dual-polarization radar;hydrometers;squallline;

利用全国雷电灾害汇编数据,结合人工观测雷暴资料、闪电定位资料和海南省统计年鉴数据,统计分析了1999至2011年海南岛的雷电灾害特征.结果表明:1999至2011年间,海南岛共上报了727起雷电灾害事故,导致了405人伤亡,其中死亡157人,受伤248人,雷击人员伤亡比率为1.58:1;海南岛雷灾事故主要发生在4至9月的午后13至18时,这与海南岛的雷电活动规律一致;海南岛雷灾事故发生最多的依次是海口和琼中;人员伤亡雷灾事故依次主要发生在田野、简易工棚、农村民居、水域和树下;财产损失雷灾事故最频繁发生在电力、石化等五大行业,占总财产损失雷灾事故的22.2％,雷灾造成的直接经济损失中酒店类最多(占34.7％);人员伤亡雷灾和财产损失雷灾与雷暴日的相关性不显著,但与生命易损模数和经济易损模数呈现较好的正相关.

Vehicle-mounted X-band dual-polarization radar, located at coastal region (118.9 E, 25.1 N) in Fujian province, almost completely captured the entire life span of a local severe thunderstorm on August 28, 2009. Combine the radar strong echo volume and hydrometers retrieved by hydrometer identification (HID) algorithm, the characteristics of cloud-to-ground (CG) flash in different stage of thunderstorm were analyzed. The study case experienced several stages and developed into a squall line in its mature stage with a maximum CG rate of 85fl/5min. CGs mainly occurred in the convective region and CG rates per 5 minutes had a linear positive correlation with strong echo volume in convective region. Seven types hydrometers was identified by HID, and five types of dominant hydrometers were found in thunderstorm, they are rain, aggregates, low-density graupel, high-density graupel, and vertical ice. The spatial distribution of hydrometers showed that rain mainly located at lower portion of thunderstorm warmer than 0°C, high-density graupel at middle, low-density graupel and vertical ice at upper portion. CG rates were also positively correlated with the samples of dominant ice phase hydrometers in convective region.

Hainan Island is located in the tropics. Both local thunderstorms (LT) and systemic thunderstorms (ST) coming from the sea are common in April to October over island. On June 10 in 2013, LT and ST met over Hainan Island and merged into one, which gradually developed into a squall line. The relationships between radar echo characteristic parameters, i.e. Combined Reflectivity (CR), Vertical integrated Liquid Water Contents (VLWC), Cloud Top Heights (CTH), 35, 40, 45, and 50 dBZ Echo Top Heights (ETH), and cloud-to-ground (CG) lightning stroke rates of this case were analyzed, using Doppler weather radar data and CG lightning location data. With the development of LT, CG lightning stroke rates increase (decrease) with the increase (decrease) of the radar parameters. CG lightning occurs mostly in the development and mature stage of LT. However, CG lightning activity in ST is just reverse, which generally happens when the radar parameters reduce. Regardless of LT, ST or squall line, the maximum values of CR, VLWC, and CTH are at least 50 dBZ, 15 kg·m-2, and 12 km, respectively, CG lightning is likely to occur. 35 dBZ ETH reached 10 km is also a good index of lightning occurrence.

From the national collected data of lightning disasters from 1998 to 2009, the observational thunderstorm data of 18 meteorological stations, and lightning locating networks data and economy and population data in statistical yearbook of Hainan Province, the indices representing hazard-formative factor, hazard pregnant environment and hazard-affected body of lightning was selected. Through R-Cluster analysis, the indices influencing vulnerability were screened and checked. Based on 5 indices, i. e., thunderstorm days, lightning density above 50 kA, thunderstorm frequency, casualty frequency and regional vulnerability economic modulus as basic variables, similarity measures of samples were calculated. With Ward's method in Q-Cluster, the hierarchy cluster analysis was carried out and Q-iterative cluster was adopted to explain and testify the result of the cluster. Finally the zoning of lightning risk in Hainan Island was constructed. Results show that Haikou City is within the first category zone, whose vulnerability is extremely high, with comprehensive vulnerability as high as 3. 89; Wencang, Chenmai, Linggao, Dingan, Tuncang and Qionghai are in the second category zone, whose vulnerability is just next to the extremely high zones; Danzhou, Qiongzhong, Baisha, Tongshi, Baoting are in the third category zone with moderate risks; Changjiang, Dongfang, Ledong,Wannin, Lingshui and Sanya are in the fourth category zone with weak risks.

With the observed thunderstorm data of 18 meteorological stations and VLF lightning locating networks data in Hainan Province, the thunderstorm environment and the characteristics of the thunderstorm activities were analyzed for the Wenchang Rocket Launching Site. The results indicate that the thunderstorm activities in the central and northern parts are stronger than those in the western, eastern and the southern coast. The Wenchang Rocket Launching Site is located in the northern area where thunderstorm activities are strong. Fitting results using the Krigine method shows that annual thunderstorm days ( Td ) of the Wenchang Rocket Launch Site have reduced gradually after 1982. Thunderstorm activities occur all the year round, and are much stronger in months from April to October than in other months, west, northwest and north of the Launch Site have stronger thunderstorm activities than other areas. 79% of the lightning currents have the strength lower than 40 kA, while only 5. 9% of the lightning currents have the strength higher than 60 kA. The occurrence of the lightning flashes has two peak time intervals in a day, one appears from 5:00 am to 6:00 am, and the another appears from 2:00 pm to 6:00 pm. The highest frequency of lightning flash activities occurs around 3:00pm in the afternoon.

Statistics analysis 19 cities in Hainan of thunderstorm data,make use of a KRIGING interpolation method,compute an average thunderstorm day for any longitude and latitude degrees in Hainan,analysis two kinds of calculation methods for lightning average density,with the artificial of thunderstorm data and lightning position system the time limit of system data for the power weigh coefficient,calculation synthesize Ng value of risk assessment.As a result show that make use of time power weigh be worth for the zone of cycle time many index sign decision TOPSIS method,calculate synthesize lightning average density to be.feasible at lightning risk assessment.

With the use of lightning location data,combined with manual observations,automatic weather station data and climate monitoring terrain information of Hainan Island in 2007,the characteristics of lightning frequency,intensity, mechanism,distribution were preliminary analyzed.The monthly frequency of lightning,the intensity changes,the main mechanism and the main factors affecting distribution were also discussed.