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云南省闪电活动时大气相对湿度结构特征
Structural Characteristics of Atmospheric Relative Humidity During Lightning Activity in Yunnan Province
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摘要: 利用2007年6月1日—8月31日云南省闪电定位系统监测的云 地闪电资料与NCEP/NCAR再分析资料中的相对湿度物理量，分析了云南省闪电活动时相对湿度的结构特征。结果表明：云南省闪电活动除具有夏季是高发期且日分布具有呈一峰一谷变化特征，在时间演变上还具有不均匀和阶段性的特点，这与特定的大气相对湿度环境条件密切相关；云南省闪电活动一般发生在相对湿度垂直结构具有低层湿度不高、中层高湿、高层又逐渐变干的环境大气中，大约在中层700 hPa以下相对湿度随高度增加，逐渐在中层形成高湿层，中层以上相对湿度又随高度减小，低层湿度不高、中层高湿、高层偏干的环境相对湿度条件非常有利于雷暴天气的发生和闪电的形成，一方面中层以下水汽随高度增加有利于水汽的上升运动和云的凝结形成，另一方面中高层水汽随高度迅速减小有利于形成上干下湿的大气对流不稳定，促使对流云进一步发展，从而产生闪电活动；低层相对湿度在40%～75%之间，中层600～700 hPa之间相对湿度较高，可达80%以上，一般为90%～95%，中层湿层越深厚，闪电过程越强烈，在高层250～400 hPa左右相对湿度减小到35%～60%之间。Abstract: Using monitored cloud ground lightning data of lightning detection system in Yunnan Province and relative humidity parameter in NCEP/NCAR data from 1 June to 31 August in 2007, structural characteristics of atmospheric relative humidity during lightning activity are analyzed. The results show that lightning activity in Yunnan is most frequent in summer because of high temperature and high humidity, and there's a daily apex which appears from 16:00 to 17:00 and a valley which appears from 08:00 to 11:00 because of daily variation of solar radiation. The lightening activity is uneven and discontinuous on day to day variation because of environmental conditions of atmospheric relative humidity. Some specific environmental humidity conditions are necessary for lightening activity. Too high humidity may restrain ascending motion of convective development, while low humidity is insufficient for convective cloud to develop. Moreover, convective development and intensification are aroused, and convective cloud developing upwards is urged by some dynamic triggering condition when unstable energy runs up to a certain extent. When electric field intensity reaches to a certain extent, the thunder phenomenon occurs. Lightning activity in Yunnan usually happens in the typical environmental atmosphere with certain vertical configuration: The relative humidity is not high at 850 hPa, but at 700 hPa it's very humid and then becomes dry at upper layers. The relative humidity increases with height below the 700 hPa, forming high moist region at the middle layer and deceases above it. This environmental condition of relative humidity is in favor of thunderstorm weather occurrence and thunder formation. First, relative humidity increase below 700 hPa is favorable for ascending motion of water vapor and cloud formation. Second, dry atmosphere at upper layers and moist atmosphere at lower layers cause convective instability so that convective cloud may be urged to develop and promote lightning activity. When lightening occurs, relative humidity at low layer is about 40%—75%, at middle layers of 600—700 hPa it is above 80% and usually reaches up to 90%—95%, and the humidity decreases to about 35%—60% at upper layers of 250—400 hPa. It is also found that deeper middle moist layer will probably result in stronger thunder process.
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图 1 2007年云南省闪电频数时间分布 (a) 月变化，(b) 日变化
Fig. 1 Temporal distribution of Yannan Province lightning frequency in 2007 (a) monthly variation, (b) diurnal variation
图 2 2007年6—8月各代表站闪电频数逐日演变 (a)6月，(b)7月，(c)8月
Fig. 2 Day-to-day variation of lightning frequency for the representative stations from June to August in 2007 (a) June, (b) July, (c) August
图 3 2007年6—8月昆明站上空逐日14：00相对湿度演变 (单位：%)(a)6月，(b)7月，(c)8月
Fig. 3 Day-to-day variation of relative humidity above Kunming Station at 14:00 from June to Augustin 2007 (unit:%) (a) June, (b) July, (c) August
图 4 2007年6—8月7次主要雷闪电过程沿102.5°E相对湿度垂直剖面合成 (单位：%)
Fig. 4 Vertical cross-section resultant diagram of relative humidity along 102.5°E for 7 times of major thunder processes from June to August in 2007 (unit:%)
图 5 2007年6月24日闪电频数时空分布 (a)0.1°×0.1°闪电频数空间分布，(b) 代表站逐时闪电频数演变
Fig. 5 Temporal and spatial distribution of lightning frequency on 24 June 2007 (a) 0.1°×0.l° spatial distribution of lightning frequency, (b) hourly variation of lightning frequency for the representative stations
图 6 2007年6月24日14：00相对湿度分布 (单位：%)(a)850hPa，(b)700hPa，(c) 沿25°N垂直剖面
Fig. 6 Relative humidity distribution at 14:0024 June 2007(unit:%) (a) 850hPa, (b)700hPa, (c) vertical cross-section along25°N
图 7 2007年8月23日闪电频数时空分布 (a)0.1°×0.1°闪电频数空间分布，(b) 代表站闪电频数逐时演变
Fig. 7 Temporal and spatial distribution of lightning frequency on 23 August2007 (a)0.1°×0.1°spatial distribution of lightning frequency, (b) hourly variation of lightning frequency for the representative stations
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[1] 许键明,孙家栋.中国气象事业发展战略研究———气象与国家安全卷.北京:气象出版社,2004:133-137. [2] 张义军,孟青,马明,等.闪电探测技术发展和资料应用.应用气象学报,2006,17(5):611-620. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=200605104&flag=1 [3] 张义军,华贵义,言穆弘,等.对流和层状云系电活动?对流及降水特性的相关分析.高原气象,1995,14 (4):396-405. http://www.cnki.com.cn/Article/CJFDTOTAL-GYQX504.001.htm [4] 冯桂力,郄秀书,袁铁,等.雹暴的闪电活动特征与降水结构研究.地球科学,2007,37(1):123-132. http://www.cnki.com.cn/Article/CJFDTOTAL-JDXK200701013.htm [5] 曹治强,李万彪.两个中尺度对流系统的降水结构和闪电特征.气象学报,2005,63(2):243-249. http://www.cnki.com.cn/Article/CJFDTOTAL-QXXB200502011.htm [6] 陈哲彰.冰雹与雷电大风的云对地闪电特征.气象学报,1995,53(3):365-374. http://www.cnki.com.cn/Article/CJFDTOTAL-QXXB503.012.htm [7] 郄秀书,张广庶,孔祥贞,等.青藏高原东北部地区夏季雷电特征的观测研究.高原气象,2003,22(3):209-216. http://www.cnki.com.cn/Article/CJFDTOTAL-GYQX200303001.htm [8] 马明,吕伟涛,张义军,等.1997—2006年我国雷电灾情特征.应用气象学报,2008,19(4):393-400. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=20080402&flag=1 [9] 冯桂力,陈文选,刘诗军,等.山东地区闪电的特征分析.应用气象学报,2002,13(3):347-355. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=20020345&flag=1 [10] 张义军,孟青,马明,等.闪电探测技术发展和资料应用.应用气象学报,2006,17(5):613-620. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=200605104&flag=1 [11] 陶诗言.中国之暴雨.北京:气象出版社,1980:1-12. [12] 蒙伟光,易燕明,杨兆礼,等.广州地区雷暴过程云-地闪特征及其环境条件.应用气象学报,2008,19(5):611-619. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=20080513&flag=1 [13] 吴亭,吕伟涛,刘晓阳,等.北京地区不同天气条件下近地面大气电场特征.应用气象学报,2009,20(4):394-401. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=20090402&flag=1 [14] Betts A K,The Parameterization of Deep Convection,The Physics and Parameterization of Moist Atmospher-ic NATO ASI Series C,1997,505:255-279. [15] 郑栋,孟青,吕伟涛,等.北京及其周边地区夏季地闪活动时空特征分析.应用气象学报,2005,16(5):638-644. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=20090402&flag=1 [16] 袁铁,郄秀书.青藏高原中部闪电活动与相关气象要素季节变化的相关分析.气象学报,2005,63(1):123-127. http://www.cnki.com.cn/Article/CJFDTOTAL-QXXB200501013.htm [17] 熊亚军,郄秀书,周筠,等.区域闪电活动对地面相对湿度的响应.地球物理学报,2006,49(2):367-374. http://www.cnki.com.cn/Article/CJFDTOTAL-DQWX200602008.htm [18] 张翠华,言穆弘,董万胜,等.青藏高原雷暴天气层结特征分析.高原气象,2005,24(5):741-747. http://www.cnki.com.cn/Article/CJFDTOTAL-GYQX200505012.htm [19] 张腾飞,张杰,郭荣芬.一条中尺度雨带的多普勒雷达回波特征及环境条件分析.应用气象学报,2005,16(1):70-77. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=20050109&flag=1 [20] 张腾飞,邓勇,谢毅然,等.“20060717"低纬高原强雷暴天气过程分析.云南大学学报(自然科学版),2008,30(2):166-174. http://www.cnki.com.cn/Article/CJFDTOTAL-YNDZ200802012.htm [21] 尹丽云,许迎杰,张腾飞,等.云南雷暴的时空分布特征分析. http://www.cqvip.com/QK/94474X/200702/24683646.html [22] 王道洪，郄秀书，郭昌明．雷电与人工引雷．上海：上海交通大学出版社，2000 -
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