Abstract
The mesoscale vortex associated with a mesoscale low-level jet (mLLJ) usually causes heavy rainfall in the col field. The col field is defined as a region between two highs and two lows, with the isobaric surface similar to a col. Using a two-dimensional shallow water model, the meso-β scale vortex couplets (MβVCs) induced by eight types of mesoscale wind perturbations in an ideal col field were numerically simulated. With the sizes of ∼100 km, the MβVCs induced by northerly perturbation (NP) and southerly perturbation (SP) moved toward the col point. The sizes of MβVCs induced by southwesterly perturbation (SWP), southeasterly perturbation (SEP), northwesterly perturbation (NWP), and northeasterly perturbation (NEP) were relatively small for the perturbations moving toward dilatation axis. The MβVC induced by easterly perturbation (EP) and westerly perturbation (WP) could not develop because they quickly moved away from the col point, before the circulation could form. The size of the circulation was determined by the distance between the vortex and the col point. The closer to the col point the vortex was, the larger the size of vortex.
The comparisons of maximum vorticity and vorticity root mean square error (RMSE) of the NP, the SWP, and the WP show that the maximum vorticity and the vorticity RMSE of the NP decreased slower than other perturbations. Therefore, the weak environment of the col field favors the maintenance of vorticity and the formation of vortex. When a mesoscale vortex forms near the col point or moves toward the col point, it may maintain a quasi-stationary state in the stable col field.
Similar content being viewed by others
References
Akiyama, T., 1973a: The large-scale aspects of the characteristic features of the Baiu front. Pap. Meteor. Geophys., 24, 157–188.
Akiyama, T., 1973b: Frequent occurrence of heavy rainfall along the north side to the low-level jet stream in the Baiu season. Pap. Meteor. Geophys., 24, 379–388.
Arritt, R. W., T. D. Rink, M. Segal, D. P. Todey, C. A. Clark, M. J. Mitchell, and K. M. Labas, 1997: The Great Plains low-level jet during the warm season of 1993. Mon. Wea. Rev., 125, 2176–2192.
Bartels, D. L., and R. A. Maddox, 1991: Midlevel cyclonic vortices generated by mesoscale convective systems. Mon. Wea. Rev., 119, 104–118.
Bei, N. F., S. X. Zhao, and S. T. Gao, 2002: Numerical simulation of a heavy rainfall event in China during July 1998. Meteor. Atmos. Phys., 80, 153–164.
Brown, R. A. 1991: Fluid Mechanics of the Atmosphere. Academic Press, Inc., 489pp.
Chen, D., Y. Q. Li, and R. H. Huang, 2007: The physical process analyses of the southwest vortex development and its effect on heavy rainfall in Eastern Sichuan under the saddle pattern background of large-scale circulations. Chinese J. Atmos. Sci., 31(2), 185–201. (in Chinese with English abstract)
Chen, L. S., and W. H. Feng, 2003: Structural evolution of the genesis and development on meso-β vortex for the “98.7” heavy rainfall: Simulation of two ways with quartet nested grid. Acta Meteorologica Sinica, 61(4), 385–395. (in Chinese with English abstract)
Chen, G. T. J., 1983: Observational aspects of the Meiyu phenomena in subtropical China. J. Meteor. Soc. Japan, 61, 306–312.
Chen, G. T. J., and C. C. Yu, 1988: Study of low-level jet and extremely heavy rainfall over northern Taiwan in the Mei-yu season. Mon. Wea. Rev., 116, 884–891.
Chen, G. T. J., and Y. S. Hsu, 1997: Composite structure of a low-level jet over southern China observed during the TAMEX period. J. Meteor. Soc. Japan, 75, 1003–1018.
Chen, G. T. J., C. C. Wang, and D. T. W. Lin, 2005: Characteristics of low-level jets over northern Taiwan in Mei-yu season and their relationship to heavy rain events. Mon. Wea. Rev., 133, 20–43.
Chen, G. T. J., C. C. Wang, and L. F. Lin, 2006: A diagnostic study of a retreating Mei-yu front and the accompanying low-level jet formation and intensification. Mon. Wea. Rev., 134, 874–896.
Chen, Q. S., 1982: The instability of the gravity-inertia wave and its relation to low-level jet and heavy rain. J. Meteor. Soc. Japan, 60, 1041–1057.
Chen, S. J., Y. H. Kuo, W. Wang, Z. Y. Tao, and B. Cui, 1998: A modeling case study of heavy rainstorms along the Mei-yu front. Mon. Wea. Rev., 126, 2330–2351.
Chen, S. S., and W. M. Frank, 1993: A numerical study of the genesis of extratropical convective mesovortices, Part I: Evolution and dynamics. J. Atmos. Sci., 50, 2401–2426.
Chu, K. K., and Z. M. Tan, 2010: Mesoscale moist adjoint sensitivity study of a Mei-yu heavy rainfall event. Adv. Atmos. Sci., 27(6), 1415–1424, doi: 10.1007/s00376-010-9213-1.
Davis, C. A., and M. L. Weisman, 1994: Balanced dynamics of mesoscale vortices produced in simulated convective systems. J. Atmos. Sci., 51, 2005–2030.
Erbes, G., 1992: A high-resolution Lax-Friedrichs scheme for hyperbolic conservation laws with source terms: Application to shallow water equations. Tech. Rep. 62, Department of Meteorology, Stockholm University, 49pp.
Erbes, G., 1993: A semi-Lagrangian method of characteristic for the shallow-water equations. Mon. Wea. Rev., 121, 3443–3452.
Fritsch, J. M., J. D. Murphy, and J. S. Kain, 1994: Warm core vortex amplification over land. J. Atmos. Sci., 51, 1780–1807.
Hamming, R. W., 1989: Digital Filters. 3rd ed., Prentice-Hall, Englewood Cliffs, New Jersey, 284pp.
Hertenstein, R. F. A., and W. H. Schubert, 1991: Potential vorticity anomalies associated with squall lines. Mon. Wea. Rev., 119, 1663–1672.
Houze, R. A., Jr., 2004: Mesoscale convective systems. Rev. Geophys., 42, RG4003, doi: 10.1029/2004RG000150.
Hu, B. W., C. G. Cui, and C. H. Fang. 2001: Causes of a two-day successively extremely heavy rain along the Changjiang valley in the eastern Hubei Province during 21–22 July 1998. Chinese J. Atmos. Sci., 25(4), 479–491. (in Chinese with English abstract)
Jiang, H., and D. J. Raymond, 1995: Simulation of a mature mesoscale convective system using a nonlinear balance model. J. Atmos. Sci., 52, 161–175.
Jiang, Y. Q., and Y. Wang. 2010: Effects of terrain on saddle pattern during the course of “98.7” extremely heavy rainstorm in the East of Hubei Province. Plateau Meteorology, 29(2), 298–308. (in Chinese with English abstract)
Jiang, Y. Q., C. Y. Wang, W. H. Zhang, and Z. Y. Chen, 2004: Numerical simulation of extremely heavy rain and meso-β scale low vortex in inverted typhoon trough. Acta Meteorologica Sinica, 18(2), 195–210.
Johnston, E. C., 1981: Mesoscale vorticity centers induced by mesoscale convective complexes. M.S. thesis, Dept. of Atmospheric and Oceanic Sciences, University of Wisconsin, 54pp.
Li, J., Y. L. Chen, and W. C. Lee, 1997: Analysis of a heavy rainfall event during TAMEX. Mon. Wea. Rev., 125, 1060–1081.
Liao, J., and Z. M. Tan, 2005: Numerical simulation of a heavy rainfall event along theMeiyu front: Influences of different scale weather systems. Acta Meteorologica Sinica, 63(5), 771–789. (in Chinese with English abstract)
Long, X., L. S. Chen, and L. J. Wen, 2006: A numerical study of the structure and evolution of meso-β scale system during “02.6” Meiyu. Chinese J. Atmos. Sci., 30(2), 327–340. (in Chinese with English abstract)
Lynch, P., and X. Y. Huang, 1992: Initialization of the HIRLAM model using a digital filter. Mon. Wea. Rev., 120, 1019–1034.
Matsumoto, S., 1973: Lower tropospheric wind speed and precipitation activity. J. Meteor. Soc. Japan, 51, 101–107.
Ninomiya, K., and T. Akiyama, 1974: Band structure of mesoscale echo clusters associated with low-level jet stream. J. Meteor. Soc. Japan, 52, 300–313.
Petterssen, S., 1956: Motion and Motion Systems. Vol. I, Weather Analysis and Forecasting, 2nd ed., McGraw-Hill, 428pp.
Ray, P. S., 1986: Mesoscale Meteorology and Forecasting. Amer. Meteor. Soc., 793pp.
Raymond, D. J., and H. Jiang, 1990: A theory for longlived mesoscale convective systems. J. Atmos. Sci., 47, 3067–3077.
Rutledge, S. A., and R. A. Houze Jr., 1987: A diagnostic modeling study of the trailing stratiform region of a midlatitude squall line. J. Atmos. Sci., 44, 2640–2656.
Sun, J. H., S. X. Zhao, G. K. Xu, and Q. T. Meng, 2010: Study on a mesoscale convective vortex causing heavy rainfall during the Mei-yu season in 2003. Adv. Atmos. Sci., 27(5), 1193–1209, doi: 10.1007/s00376-009-9156-6.
Tao, S. Y., 1980: The Torrential Rain in China. Science Press, Beijing, 225pp. (in Chinese)
Wang, Z., and K. Gao, 2006: Adjoint sensitivity experiments of a meso-β-scale vortex in the middle reaches of the Yangtze River. Adv. Atmos. Sci., 23(2), 267–281, doi: 10.1007/s00376-006-0267-z.
Xu, W. H., Y. Q. Ni, X. K. Wang, X. X. Qiu, X. H. Bao, and W. Y. Jin, 2011: A study of structure and mechanism of a meso-beta-scale convective vortex and associated heavy rainfall in the Dabie Mountain area Part I: Diagnostic analysis of the structure. Adv. Atmos. Sci., 28(5), 1159–1176, doi: 10.1007/s00376-010-0170-5.
Xu, Y. M., and K. Gao. 2002: Simulation and analysis of meso-β vortex over middle reaches of the Yangtse River on 22 July 1998. Acta Meteorologica Sinica, 60(1), 85–95. (in Chinese with English abstract)
Yu, Z. H., M. Q. Miao, Q. R. Jiang, and P. Z. Yang, 2004: Hydrodynamics. China Meteorological Press, Beijing, 378pp. (in Chinese)
Zhai, G. Q., L. L. Zhou, and Z. Wang, 2007: Analysis of a group of weak small-scale vortexes in the planetary boundary layer in the Mei-yu front. Adv. Atmos. Sci., 24(3), 399–408, doi: 10.1007/s00376-007-0399-9.
Zhang, D. L., and J. M. Fritsch, 1988: A numerical investigation of a convectively generated, inertially stable, extratropical warm-core mesovortex over land. Part I: Structure and evolution. Mon. Wea. Rev., 116, 2660–2687.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Jiang, Y., Wang, Y. & Huang, H. A study on the dynamic mechanism of the formation of mesoscale vortex in col field. Adv. Atmos. Sci. 29, 1215–1226 (2012). https://doi.org/10.1007/s00376-012-1186-9
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00376-012-1186-9