Numerical Simulation and Potential Vorticity Diagnosis of an Eastward Moving Southwest Vortex

  • LIU Xiaoran ,
  • LI Guoping
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  • Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China;2. University of Chinese Academy of Sciences, Beijing 100049, China;3. Chongqing Climate Center, Chongqing 401147, China;4. College of Atmospheric Sciences, Chengdu University of Information Technology, Chengdu 610225, China

Received date: 2013-03-07

  Online published: 2014-10-28

Abstract

By using non-hydrostatic mesoscale WRF (Weather Research Forecast) model, an eastward moving southwest vortex process producing heavy precipitation is simulated in high resolution. The simulation is triple nesting with the highest resolution of 5 km. The results show that the WRF model successfully simulate the area and movement of heavy precipitation caused by the southwest vortex. The southwest vortex establishes on 850 hPa firstly, and then develops upward to 700 hPa after 9 h. There is convergence, positive vorticity, potential vorticity in the lower troposphere both in newborn and mature stages of the Southwest Vortex. And the strong vertical movement, positive vorticity and potential vorticity can significantly strengthen to the upper troposphere (300 hPa). The water vapor flux divergence has good indication to strength and movement of the heavy precipitation. The potential vorticity diagnostic analysis shows that vertical configuration of the diabatic heating term is contrary to that of vertical flux divergence term. The diabatic heating term caused by the release of latent heat is beneficial to the growth of low-level potential vorticity and inhibition of the growth of high-level potential vorticity. The latent heat is in favor of the generation and development of the southwest vortex.

Cite this article

LIU Xiaoran , LI Guoping . Numerical Simulation and Potential Vorticity Diagnosis of an Eastward Moving Southwest Vortex[J]. Plateau Meteorology, 2014 , 33(5) : 1204 -1216 . DOI: 10.7522/j.issn.1000-0534.2013.00151

References

[1]陈忠明,闵文彬,崔春光. 西南低涡研究的一些新进展[J]. 高原气象,2004,23(增刊1):1-5.
[2]蒋璐君,李国平,母灵, 等. 基于TRMM资料的西南涡强降水结构分析[J]. 高原气象, 2014, 33(3): 607-614, doi: 10.7522/j.issn.1000-0534.2013.00094.
[3]赵大军,江玉华,李莹. 一次西南低涡暴雨过程的诊断分析与数值模拟[J]. 高原气象,2011,30(5): 1158-1169.
[4]何光碧. 西南低涡研究综述[J]. 气象,2012,38(2): 155-163.
[5]江玉华,杜钦,赵大军,等. 引发四川盆地东部暴雨的西南低涡结构特征研究[J]. 高原气象,2012,31(6): 1562-1573.
[6]张虹,李国平,王曙东. 西南涡区域暴雨的中尺度滤波分析[J]. 高原气象, 2014, 33(2): 361-371, doi: 10.7522/j.issn.1000-0534.2013.00016.
[7]康岚,郝丽萍,牛俊丽. 引发暴雨的西南低涡特征分析[J]. 高原气象,2011,30(6): 1435-1443.
[8]李明,高维英,侯建忠,等. 一次西南涡东北移对川陕大暴雨影响的分析[J]. 高原气象, 2013, 32(1): 133-144, doi: 10.7522/j.issn.1000-0534.2013.00014.
[9]Wu G X,Chen S J. The effect of mechanical forcing on the formation of a mesoscale vortex[J]. Quart J Roy Meteor Soc, 1985, 111: 1049-1070.
[10]高守亭. 流场配置及地形对西南低涡形成的动力作用[J]. 大气科学,1987,11(3):263-271.
[11]吴国雄,刘还珠. 全型垂直涡度倾向方程和倾斜涡度发展[J]. 气象学报,1999,57(1):1-15.
[12]邹波,陈忠明. 一次西南低涡发生发展的中尺度诊断[J]. 高原气象,2000,19(2):141-149.
[13]赵思雄,傅慎明. 2004年9月川渝大暴雨期间西南低涡结构及其环境场分析[J]. 大气科学,2007,31(6):1059-1075.
[14]Fu S M, Sun J H, Zhao S X, et al. The energy budget of a southwest vortex with heavy rainfall over South China[J]. Adv Atmos Sci, 2011, 28(3):709-724.
[15]Wang Z, Gao K. Sensitivity experiments of an eastward-moving southwest vortex to initial perturbations[J]. Adv Atmos Sci, 2003, 20(4):638-649.
[16]陈栋,李跃清,黄荣辉. 鞍型大尺度环流背景下西南低涡发展的物理过程分析及其对川东暴雨发生的作用[J]. 大气科学,2007,31(2):185-201.
[17]李云川,张迎新,马翠平,等. 热带低压远距离对西南涡稳定加强的作用[J]. 高原气象,2012,31(6): 1551-1561.
[18]Chen S J, Lorenzo D. Numerical prediction of the heavy rainfall vortex over the eastern Asia monsoon region[J]. J Meteor Soc Japan, 1984, 62(5):730-747.
[19]Kuo Y, Cheng L S, Anthes R A. Mesoscale analyses of Sichuan flood catastrophe 11-15 July 1981[J]. Mon Wea Rev, 1986, 114: 1984-2003.
[20]Kuo Y, Cheng L S, Bao J W. Numerical simulation of the 1981 Sichuan flood. Part Ⅰ: Evolution of a mesoscale southwest vortex[J]. Mon Wea Rev, 1988, 116: 2481-2504.
[21]段海霞,陆维松,毕宝贵. 凝结潜热与地表热通量对一次西南低涡暴雨影响分析[J]. 高原气象,2008,27(6):1315-1321.
[22]赵玉春,王叶红. 高原涡诱生西南涡特大暴雨成因的个例研究[J]. 高原气象,2010,29(4):819-831.
[23]陈涛,张芳华,端义宏. 广西“6.12”特大暴雨中西南涡与中尺度对流系统发展的相互关系研究[J].气象学报,2011,69(3):472-485.
[24]赵兵科,吴国雄,姚秀萍. 2003年夏季梅雨期一次强气旋发展的位涡诊断分析[J]. 大气科学,2008,32(6):1241-1255.
[25]Emanuel K A, Fantini M, Thorpe A J. Baroclinic instability in an environment of small stability to slantwise moist convection[J]. J Atmos Sci, 1987, 44: 1559-1587.
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