A squall line process as the research object which occurs on 20 May 2013,at Sanshui in Guangdong has been selected.Firstly,the precipitation process is divided into three stages by the distribution of radar echo over time and height and the characteristics when the squall line moving towards Sanshui.Secondly,analyzing the change of the raindrop spectrum in this precipitation by calculating the number density of total particles、the median diameter and peak number.Thirdly,stating the relationships between echo and precipitation intensity in the whole process and the grading process respectively according to the data of raindrop spectrum,then discussing the influence of raindrop spectrum's change and radar echo on the rainfall estimation.The following conclusions have been given:The median diameter in stages of convective cloud precipitation is basically in line with stratiform cloud precipitation stages,but its number density is much greater.Convective cloud precipitation phase is given priority to two peaks,and when the precipitation reaches to a stratiform one,the ratio of multi-peak spectrum is increasing.Radar echo is often less than the reflectivity calculated by HSC-OTT Parsivel,their correlation increases with descent height.Between the relationship of echo and precipitation intensity,b fluctuates within the range of 1~2,however,a has major fluctuation,especially when the convective cloud precipitation stages progressing towards stratiform clouds,a value increases and b value decreases;Then a segmented relationship between echo and precipitation intensity is defined according to the characteristics of three stages,the precipitation's inversion of segmented relationship is much better,the relative error given by raindrop spectrum is minimal in the period of transition,but the inversion accuracy in stratiform cloud precipitation stages is higher than convective clouds,which bears on the rapid and dramatic changes of convective clouds raindrop spectrum and its rainfall intensity;In the aspect of radar observations,the precipitation inversion of segmented relationship is better,the deviation caused by radar is smaller in convective clouds,but this value will be higher when the type of precipitation transits to stratiform clouds,which is mainly due to the the minimum error between the distrometer and radar in the phase of convection,the differences of two instruments on time and height,the precision of radar observation and the changes of raindrops spectrum also have important influence on rainfall estimation.
Key words
Raindrop size distri /
Z-R relatio /
Precipitation estima
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References
[1]Brown Jr P S.1987.Parameterization of drop-spectrum evolution due to coalescence and breakup[J].J Atmos Sci,44(1):242-249.
[2]Cataneo R,Stout G E.1968.Raindrop-size distribution in humid continental climates,and associated rainfall rate-radar reflectivity relationships[J].J Appl Meteor,7(5):901-907.
[3]Rosenfeld D,Ulbrich C W.2003.Cloud microphysical properties,processes and rainfall estimation opportunities[J].Meteorological Monographs,30(52):237-258.
[4]Stout G E,Mueller E A.1968.Survery of relationships between rainfall rate and radar reflectivity in the measurement of precipitation[J].J Appl Meteor,7(3):465-474.
[5]陈磊,陈宝君,杨军,等.2013.2009-2010年梅雨锋暴雨雨滴谱特征[J].大气科学学报,36(4):481-488.Chen Lei,Chen Baojun,Yang Jun,et al.2013.Characteristics of raindrop size distribution of rainstorm on Meiyu front during 2009-2010[J].Transact Atmos Sci,36(4):481-488.
[6]邓雪娇,黄浩辉,吴兑.1996.广州地区汛期强降水的微物理特征[J].热带气象学报,12(2):167-173.Deng Xuejiao,Huang Haohui,Wu Dui.1996.The micro-features of heavy rain over Guangzhou area in rainy season[J].J Trop Meteor,12(2):167-173.
[7]冯雷,陈宝君.2009.利用PMS的GBPP-100型雨滴谱仪观测资料确定 关系[J].气象科学,29(2):192-198.Feng Lei,Chen Baojun.2009.The Radar reflectivity-rainrate relationship as inferred from ground-based raindrop spectra observed by GBPP-100 probe[J].Sci Meteor Sinica,29(2):192-198.
[8]胡娅敏,沈桐立,廖菲.2005.一次河南省春季层状云降水的地面雨滴谱特征[J].南京气象学院学报,28(4):507-515.Hu Yamin,Shen Tongli,Liao Fei.2005.Characteristics of the surface raindrop size distribution of spring stratiformis precipitation in Henan Province[J].J Nanjing Insti Meteor,28(4):507-515.
[9]李德俊,杨剑超,蔡定军,等.2009.降雨型滴谱与反射率因子及雨强关系研究[J].气象与减灾研究,32(4):39-44.Li Dejun,Yang Jianchao,Cai Dingjun,et al.2009.Raindrop size distribution and the relationship between rainfall rate and reflectivity[J].Meteor Disaster Reduction Res,32(4):39-44.
[10]廖菲,邓华,万齐林,等.2011.珠江三角洲地区两次夏季典型雷电天气系统的雨滴谱特征观测研究[J].高原气象,30(3):798-808.Liao Fei,Deng Hua,Wan Qilin,et al.2011.Observation studies on characteristics of raindrop size distribution of two typical summer thunderstorm cases in the Pearl River Delta[J].Plateau Meteor,30(3):798-808.
[11]刘红燕,陈洪滨,雷恒池,等.2008.利用2004年北京雨滴谱资料分析降水强度和雷达反射率因子的关系[J].气象学报,66(1):125-129.Liu Hongyan,Chen Hongbin,Lei Hengchi,et al.2008.Relationship between rain rate and radar reflectivity based on the raindrop distribution data in Beijing during 2004[J].Acta Meteor Sini,66(1):125-129.
[12]刘红燕,雷恒池.2006.基于地面雨滴谱资料分析层状云和对流云降水的特征[J].大气科学,30(4):693-702.Liu Hongyan,Lei Hengchi.2006.Characteristics of rain from stratiform versus convective cloud based on the surface raindrop data[J].Chinese J Atmos Sci,30(4):693-702.
[13]牛生杰,安夏兰,桑建人.2002.不同天气系统宁夏夏季降雨谱分布参量特征的观测研究[J].高原气象,21(1):37-44.Niu Shengjie,An Xialan,Sang Jianren.2002.Observational research on physical feature of summer raindrop size distribution under synoptic system in Ningxia[J].Plateau Meteor,21(1):37-44.
[14]石爱丽,郑国光,黄庚,等.2004.2002年秋季河南省层状云降水的雨滴谱特征[J].气象,30(8):12-17.Shi Aili,Zheng Guoguang,Huang Geng,et al.2004.Characteristics of raindrop spectra of stratiform cloud precipitation in autumn 2002 in Henan Province[J].Meteor Mon,30(8):12-17.
[15]王改利,赵翠光,刘黎平,等.2013.雷达回波外推预报的误差分析[J].高原气象,32(3):874-883.Wang Gaili,Zhao Cuiguang,Liu Liping,et al.2013.Error analysis of radar echo extrapolation[J].Plateau Meteor,32(3):874-883.DOI:10.7522/j.issn.1000-0534.2012.00081.
[16]王红艳,刘黎平,王改利,等.2009.多普勒天气雷达三维数字组网系统开发及应用[J].应用气象学报,20(2):214-224.Wang Hongyan,Liu Liping,Wang Gaili,et al.2009.Development and application of the Doppler weather radar 3-D digital mosaic system[J].J Appl Meteor Sci,20(2):214-224.
[17]王蕙莹,王振会,杨通晓,等.2013.双基地雷达系统探测椭球雨滴群时主站仰角对探测性能的影响[J].高原气象,32(4):1165-1173.Wang Huiying,Wang Zhenhui,Yang Tongxiao,et al.2013.Effects of transmitting antenna elevation on bistatic polarization radar system ability detecting rotatory spheroidal raindrops[J].Plateau Meteor,32(4):1165-1173.DOI:10.7522/j.issn.1000-0534.2012.00110.
[18]王鹏飞,李子华.1989.微观云物理学[M].北京:气象出版社,406-408.Wang Pengfei,Li Zihua.1989.The Micro Cloud Physics[M].Beijing:China Meteorological Press,406-408.
[19]肖现,廖菲,肖辉,等.2010.北京对流性降水的雨滴尺寸分布瞬时特征与雷达降水的关系[J].热带气象学报,26(4):445-451.Xiao Xian,Liao Fei,Xiao Hui,et al.2010.Systematic variation of drop size in convective of Beijing and radar-rainfall relations[J].J Trop Meteor,26(4):445-451.
[20]肖艳姣,万玉发,吴涛,等.2015.基于多普勒天气雷达的两种垂直风廓线反演方法的对比分析[J].高原气象,34(1):288-297.Xiao Yanjiao,Wan Yufa,Wu Tao,et al.2015.Intercomparison of vertical wind profiles retrieved using two techniques from Doppler weather radar[J].Plateau Meteor,34(1):288-297.DOI:10.7522/j.issn.1000-0534.2013.00136.
[21]张丰伟,刘晓莉,桑建人,等.2011.宁夏夏季层状暖云降水观测研究[J].高原气象,30(2):471-481.Zhang Fengwei,Liu Xiaoli,Sang Jianren,et al.2011.Observation study on precipitation mechanism of stratiform warm cloud in Ningxia in summer[J].Plateau Meteor,30(2):471-481.
[22]张鸿发,徐宝祥,蔡启铭.1989.由雨滴谱型订正雷达测量降水的一种方法[J].高原气象,8(1):75-79.Zhang Hongfa,Xu Baoxiang,Cai Qiming.1989.A method of precipitation with radar measurement corrected with the pattern of raindrop size distribution[J].Plateau Meteor,8(1):75-79.
[23]张培昌,杜秉玉,戴铁丕.2001.雷达气象学[M].北京:气象出版社,171-181.Zhang Peichang,Du Bingyu,Dai Tiepi.2001.Radar Meteorology[M].Beijing:China Meteorological Press,171-181.