利用WRF 模式对2012 年5 月10-11日甘肃岷县的一次强降水过程进行了数值模拟和诊断分析。结果表明:WRF模式较好地再现了此次暴雨天气过程,在暴雨落区和强度量级上接近实况。四川盆地的西南风从孟加拉湾携带暖湿水汽向北输送,最大值达到16 kg·m-1·s-1·hPa-1,为该地区降水提供了水汽条件。在暴雨发生前,大气能量有个累积的阶段,在暴雨发生时能量开始释放,到暴雨结束时能量释放完;在暴雨发生时,降水落区上空整层均为上升气流,中心强度达到0.5 m·s-1。这种强上升运动不仅使得暖湿空气辐合抬升,而且在上升过程中释放潜热,加热大气,使得垂直运动增强,形成正反馈。模拟的CAPE和雷达反射率因子等物理量均对此次降水过程有较好的指示意义。
WRF model was used to numerical simulation and diagnostic analyze on a rainstorm occurred in Min county,Gansu Province on 10 May 2012.The results illustrate that:The WRF model is potential in simulating and predicting this precipitation process,including the rainfall area and intensity.This precipitation was fed by a southwesterly flow around Sichuan basin which carried warm and moist air from Bengal Bay,and the maximum value of water vapor flux was up to 16 kg·m-1·s-1·hPa-1.Before the rainstorm,the atmospheric energy was accumulated and stored.The energy was released at the beginning of the rainfall and dissipated by the end of the rainstorm.During this precipitation,the whole atmospheric layer was ascending,and the maximum value of vertical speed was up to 0.5 m·s-1.This ascending motion not only made the warm and moist air convergence but also released latent heat and heated atmosphere,hence a positive feedback was formed and the vertical movement was strengthen.The precipitation process can be explored through the simulation of the CAPE and radar reflectivity factor and other physic index from the WRF model.
[1]Doswell C A,Rasmussen E N.1994.The effect of neglecting the virtual temperature correction on cape calculations[J].Wea Forecasting,9(4):625-629.
[2]谌芸,李泽椿.2005.青藏高原东北部区域性大到暴雨的诊断分析及数值模拟[J].气象学报,63(3):289-300.Chen Yun,Li Zechun.2005.Diagnostic analysis and numerical simulation on a regional heavy-hard rain in northeast Qinghai-Xizang Plateau[J].Acta Meteor Sinica.63(3):289-300.
[3]杜继稳,李明娟,张弘,等.2004.青藏高原东北侧突发性暴雨地面能量场特征分析[J].高原气象,23(4):453-457.Du Jiwen,Li Mingjuan,Zhang Hong,et al.2004.Characterastic analysis on surface energy field of abrupt rainstrom on the northeast side of Qinghai-Xizang Plateau[J].Plateau Meteor,23(4):453-457.
[4]郭大梅,刘勇,马晓华,等.2015.一次异常路径持续强降水中尺度对流系统分析[J].高原气象,2015,34(6):1648-1657.Guo Damei,Liu Yong,Ma Xiaohua,et al.2015.Analysis on unusual path associated with mesoscale convective system in a continuous heavy rain[J].Plateau Meteor,34(6):1648-1657.DOI:10.7522/j.issn.1000-0534.2014.00076.
[5]何由,阳坤,姚檀栋,等.2012.基于WRF模式对青藏高原一次强降水的模拟[J].高原气象,31(5):1183-1191.He You,Yang Kun,Yao Tandong,et al.2012.Numerical simulation of a heavy precipitation in Qinghai-Xizang Plateau based on WRF model[J].Plateau Meteor,31(5):1183-1191.
[6]姜学恭,李夏子,李彰俊,等.2012.一次阻塞型华北对流性暴雨过程的诊断分析和数值模拟[J].高原气象,31(5):1283-1293.Jiang Xuegong,Li Xiazi,Li Zhangjun,et al.2012.Diagnosis and numerical simulation of a convective rainstorm porcess of block type occurred in North China[J].Plateau Meteor,31(5):1283-1293.
[7]井喜,李栋梁,李明娟,等.2008.青藏高原东北侧一次突发性大暴雨环境场综合分析[J].高原气象,27(1):46-57.Jing Xi,Li Dongliang,Li Mingjuan,et al.2008.Synthetic analyses on environmental conditions of an abrupt heavy rainstorm on the northeast side of Tibetan Plateau[J].Plateau Meteor,27(1):46-57.
[8]李安泰,何宏让,张云.2012.WRF模式陆面参数扰动对一次西北暴雨影响的数值模拟[J].高原气象,31(1):65-75.Li Antai,He Hongrang,Zhang Yun.2012.Numerical simulation of effect of WRF land surface parameter disturbance on a rainstorm in Northwest China[J].Plateau Meteor,31(1):65-75.
[9]栾晨,宋敏红,蔡英,等.2012.西北区西部夏半年强降水分布与变化特征[J].高原气象,31(3):629-637.Luan Chen,Song Minhong,Cai Ying,et al.2012.Distribution and change feature of intense precipitation in the west part of Northwestern China during summer half years[J].Plateau Meteor,31(3):629-637.
[10]蒙伟光,王安宇,李江南,等.2004.华南暴雨中尺度对流系统的形成及湿位涡分析[J].大气科学,28(3):330-341.Meng Weiguang,Wang Anyu,Li Jiangnan,et al.2004.Moist potential vorticity analysis of the heavy rainfall and mesoscale convective systems in South China[J].Chinese J Atmos Sci.28(3):330-341.
[11]牛金龙,黄楚惠,李国平,等.2015.基于高分辨率资料的湿螺旋度指标及其对成都强降水的预报应用[J].高原气象,34(4):942-949.Niu Jinlong,Huang Chuhui,Li Guoping,et al.2015.Moist helicity indexes selection and checking in Chengdu region for heavy rainfall based on the fine data[J].Plateau Meteor,34(4):942-949.DOI:10.7522/j.issn.1000-0534.2014.00053.
[12]任余龙,寿绍文,李耀辉.2007.西北区东部一次大暴雨过程的湿位涡诊断与数值模拟[J].高原气象,26(2):344-352.Ren Yulong,Shou Shaowen,Li Yaohui.2007.Numerical Simulation and moist potential vorticity diagnostic analyses of a heavy rain process in eastern part of Northwest China[J].Plateau Meteor,26(2):344-352.
[13]王劲松,李耀辉,康凤琴,等.2002.西北区东部一次暴雨的数值模拟试验[J].高原气象,21(3):258-266.Wang Jinsong,Li Yaohui,Kang Fengqin,et al.2002.Numerical simulation experiment of torrential rain event in east of North-West China[J].Plateau Meteor,21(3):258-266.
[14]徐双柱,邹立维.2008.一次梅雨期暴雨的中尺度数值模拟分析[J].暴雨灾害,27(1):17-23.Xu Shuangzhu,Zhou Liwei.2008.Numerical simulation analysis of a heavy rain during Meiyu season[J].Torrential Rain and Disaster,27(1):17-23.
[15]赵玉春,许小峰,崔春光.2012.中尺度地形对梅雨锋暴雨影响的个例研究[J].高原气象,31(5):1268-1282.Zhao Yuchun,Xu Xiaofeng,Cui Chunguang.2012.Case study of the impact of mesoscale topography on the Meiyu frontal rainstorm[J].Plateau Meteor,31(5):1268-1282.
