设为首页
加入收藏
Impacts of Raindrop Velocity Measurement Error on Raindrop Size Distribution Estimation from PARSIVEL Disdrometer
-
摘要: 该文研究PARSIVEL激光雨滴谱仪的测量误差并提出订正方法。对2014年在广东阳江的PARSIVEL激光雨滴谱仪采集的两次降水过程数据进行分析发现，雨滴下落速度V随粒径D变化与静止大气中雨滴下落末速度随粒径变化的Atlas-Ulbrich曲线分布趋势一致，但D < 1 mm及D > 3 mm的速度偏差较大。其主要原因是大粒径雨滴形变造成速度偏离较大，仪器测量误差造成小粒径测速偏大，激光雨滴谱仪所在高度的大气垂直运动影响雨滴下落速度。根据PARSIVEL激光雨滴谱仪测量原理，基于雨滴形变与粒径关系，给出形变订正后的Atlas-Ulbrich修正曲线，并用于对小粒径测速订正。比较订正前后的雨滴谱分布，订正后的小雨滴浓度明显增加，大雨滴浓度略有减小，订正后浓度参数和斜率参数均增加，形状参数变化不明显。
-
关键词:
- 激光雨滴谱仪;
- 测量误差;
- Atlas-Ulbrich修正曲线;
- 雨滴谱分布
Abstract: The error of raindrop size distribution estimation using PARSIVEL disdrometer is carefully studied, and an error correction method is proposed. Raindrop distribution data of two kind of precipitation by PARSIVEL disdrometer at Yangjiang in 2014 are analyzed. Results show that, the measured raindrop size distribution data are in good consistency with the empirical curve from Atlas, but the velocity measurement error is large when the particle size is below 1 mm or above 3 mm. The error analysis indicates that velocity measurement error of big particle is caused by deformation, while the error of small particle is caused by the instrument itself, and the vertical air motion near the disdrometer is influential for both situations.According to the detective principle of PARSIVEL disdrometor and the relationship between the deformation particle, a corrected Atlas-Ulbrich curve is given. The detective data of stratiform cloud precipitation are stable. An correction error curve of small particles is given by calculating the vertical air velocity of no less than 1 mm in diameter data from the stable precipitation, excluding the air motion in the diameter less than 1 mm. Small particle data are corrected, and the corrected raindrop distribution data are in good consistency with corrected Atlas-Ulbrich curve. The droplet concentration increases significantly and large drops concentration reduce slightly after correction. The intercept, slope and shape parameters of Gamma distribution of two kinds of precipitations are calculated before and after the correction, and the comparison shows that the corrected intercept parameter and slope parameter increase obviously, while the shape parameter barely changes. -
图 1 2014年5月8日C-FMCW雷达探测层状降水云时序图与地面雨滴分布
(a) 回波强度，(b) 径向速度，(c) 地面雨滴分布及Atlas-Ulbrich曲线
Fig. 1 Stratiform cloud evolution sequence diagram and raindrop distribution by C-FMCW on 8 May 2014
(a) reflectivity, (b) radial velocity, (c) raindrop distribution and Atlas-Ulbrich curve
图 2 2014年5月10日C-FMCW雷达探测对流云降水时序图与地面雨滴分布
(a) 回波强度，(b) 径向速度，(c) 地面雨滴分布及Atlas-Ulbrich曲线
Fig. 2 Convective cloud evolution sequence diagram and raindrop distribution by C-FMCW on 10 May 2014
(a) reflectivity, (b) radial velocity, (c) raindrop distribution and Atlas-Ulbrich curve
图 3 PARSIVEL测得的雨滴分布和Vb-Da修正曲线
(a) 层状云降水，(b) 对流云降水
Fig. 3 Raindrop data distribution after curve revised
(a) the stratiform precipitation, (b) the convective precipitation
图 4 2014年5月8日层状云降水近地面 (1.4 m) 大气平均垂直运动速度
Fig. 4 The average vertical velocity of air motion near the ground (1.4 m) at stratiform precipitation on 8 May 2014
图 5 小粒径测速误差分布订正曲线
(a) 大气垂直运动速度订正后小粒径雨滴分布与Vb-Da曲线，(b) 平均测速误差ΔV随粒径分布
Fig. 5 Velocity error distribution of small particle
(a) small particle distribution and Vb-Da curve, (b) velocity error distribution
图 6 测速修正后的雨滴分布和Vb-Da曲线
(a) 层状云，(b) 对流云
Fig. 6 Velocity revised of small particle and Vb-Da curve
(a) the stratiform precipitation, (b) the convective precipitation
图 7 对流云降水0.937 mm粒子数 (a) 和1.375 mm粒子数 (b) 与近地面大气平均垂直速度关系
Fig. 7 Relatioships between the number of 0.937 mm particles (a), the number of 1.375 mm particles (b) of convective precipitation and the average vertical velocity of the air motion near the ground
表 1 层状云降水Gamma函数3个参数订正前后比较
Table 1 Three parameters of the Gamma distribution before and after correction of the stratiform precipitation
时间 订正前 订正后 N0/(m-3·mm-1-μ) μ Λ/mm-1 N0/(m-3·mm-1-μ) μ Λ/mm-1 20:18-20:29 1.98×104 3.98 5.07 2.58×104 3.71 5.19 20:30-20:41 3.55×104 3.51 5.40 4.48×104 3.20 5.50 
下载: 导出CSV
表 2 对流云降水Gamma函数3个参数订正前后比较
Table 2 Three parameters of the Gamma distribution before and after correction of the convective precipitation
时间 订正前 订正后 N0/(m-3·mm-1-μ) μ Λ/mm-1 N0/(m-3·mm-1-μ) μ Λ/mm-1 19:00-19:14 1.20×103 -0.25 1.41 1.70×103 -0.07 1.63 19:15-19:29 1.59×103 0.21 1.34 2.22×103 0.27 1.52 19:30-19:44 2.08×103 0.54 1.51 2.94×103 0.73 1.73 19:45-19:59 2.22×103 0.06 1.34 3.08×103 0.15 1.52
下载: 导出CSV
-
[1] 窦贤康, 刘万栓, Amayenc P, 等.机载雷达定量测雨中雨滴谱参数的优化.应用气象学报, 1999, 10(3):293-298. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=19990371&flag=1 [2] 周毓荃, 刘晓天, 周非非, 等.河南干旱年地面雨滴谱特征.应用气象学报, 2001, 12(增刊Ⅰ):39-47. http://www.cnki.com.cn/Article/CJFDTOTAL-YYQX2001S1005.htm [3] 柳臣中, 周筠琨, 谷娟, 等.成都地区雨滴谱特征.应用气象学报, 2015, 26(1):112-121. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=20150112&flag=1 [4] 严采繁, 陈万奎.对流层下部雨滴谱分布.应用气象学报, 1990, 1(2):191-198. http://qikan.camscma.cn/jams/ch/reader/view_abstract.aspx?file_no=19900227&flag=1 [5] 张培昌, 杜秉玉, 戴铁丕.雷达气象学.北京:气象出版社, 2000:172-175. [6] 安英玉, 金凤岭, 张云峰, 等.地面雨滴谱观测的图像自动识别方法.应用气象学报, 2008, 19(2):188-193. doi: 10.11898/1001-7313.20080234 [7] Kinnell P I A.Some observations on the Joss-Waldvogelrainfall disdrometer.J Appl Meteor, 1976, 15:499-502. doi: 10.1175/1520-0450(1976)015<0499:SOOTJW>2.0.CO;2 [8] Tokay A, Walff D B, Wolff K R, et al.Rain gauge and disdrometer measurements during the Keys Area Microphysics Project (KAMP).J Atmos Ocean Technol, 2003, 20:1460-1477. doi: 10.1175/1520-0426(2003)020<1460:RGADMD>2.0.CO;2 [9] Martin LÖffler-Mang, Joss Jurg.An optical disdrometer for measuring size and velocity of hydrometeors.J Atmos Ocean Technol, 1999, 17:130-138. https://www.researchgate.net/publication/245354371_An_Optical_Disdrometer_for_Measuring_Size_and_Velocity_of_Hydrometeors [10] Thurai M, Tokay C, Schultz C, et al.Drop size distribution comparisons between Parsivel and 2D video disdrometer.Adv Geosci, 2011, 30:3-9. doi: 10.5194/adgeo-30-3-2011 [11] Yuter S E, Kingsmill D E, Nance L B, et al.Observations of precipitation size and fall speed characteristics within coexisting rain and wet snow.J Appl Meteor Climatol, 2006, 45:1450-1464. doi: 10.1175/JAM2406.1 [12] 濮江平, 张伟, 姜爱军.利用激光降水粒子谱仪研究雨滴谱分布特性.气象科学, 2010, 30(5):702-707. http://www.cnki.com.cn/Article/CJFDTOTAL-QXKX201005017.htm [13] Gunn R, Kinzer G D.The terminal velocity of fall for water droplets in stagnant air.J Meteor, 1949, 6:243-248. doi: 10.1175/1520-0469(1949)006<0243:TTVOFF>2.0.CO;2 [14] Atlas D, Ulbrich C W.Path and area integrated rainfall measurement by microwave in the 1~3 cm band.J Appl Meter, 1977, 16(12):1322-1331. doi: 10.1175/1520-0450(1977)016<1322:PAAIRM>2.0.CO;2 [15] Niu Shengjie, Jia Xingcan.Distributions of raindrop size and fall velocity in a semiarid plateau climate:Convective versus stratiformrains.J Appl Meteor Climatol, 2009, 49:632-645. https://www.deepdyve.com/lp/american-meteorological-society/distributions-of-raindrop-sizes-and-fall-velocities-in-a-semiarid-Bsbwbnrnxd [16] 王可法, 张卉慧, 张伟, 等.Parsivel激光雨滴谱仪观测降水中异常数据的判别及处理.气象科学, 2011, 31(6):732-736. http://www.cnki.com.cn/Article/CJFDTOTAL-QXKX201106010.htm [17] 顾震潮.云雾降水物理基础.北京:科学出版社, 1980. [18] Andsager K, Beard K V, Laird N F.Laboratory measurements of axis ratios for large rain drops.Atmos Sci, 1999, 56:2673-2683. doi: 10.1175/1520-0469(1999)056<2673:LMOARF>2.0.CO;2 [19] Jaffrain J, Berne A.Experimental quantification of the sampling uncertainty associated with measurements from Parsiveldisdrometers.Journal of Hydromerology, 2010, 12:352-368. https://www.researchgate.net/publication/49460392_Experimental_Quantification_of_the_Sampling_Uncertainty_Associated_with_Measurements_from_PARSIVEL_Disdrometers [20] 张舒婷, 牛生杰, 林文, 等.夏季雷州半岛强降水雨滴谱个例分析及降水与闪电相关性统计分析.大气科学学报, 2014, 37(4):476-483. http://www.cnki.com.cn/Article/CJFDTOTAL-NJQX201404011.htm [21] Jameson A R, Kostinski A B.Fluctuation properties of precipitation.PartⅡ:Reconsideration of the meaning and measurement of raindrop size distribution.J Atmosic Sci, 1997, 55:283-294. doi: 10.1175/1520-0469%281998%29055<0283%3AFPOPPI>2.0.CO%3B2 [22] Ulbrich C W, Atlas D.Rainfall microphysics and radar properties: Analysis methods for drop size spectra.J Applied Meteor, 1997, 37:912-922. https://www.researchgate.net/publication/240686064_Rainfall_Microphysics_and_Radar_Properties_Analysis_Methods_for_Drop_Size_Spectra -
计量
- 摘要浏览量: 5025
- HTML全文浏览量: 1276
- PDF下载量: 1322
- 被引次数: 0
