Dependence of Polar Low Development on Baroclinicity and Physical Processes: An Idealized High-Resolution Numerical Experiment

Wataru Yanase Ocean Research Institute, University of Tokyo, Tokyo, Japan

Search for other papers by Wataru Yanase in
Current site
Google Scholar
PubMed
Close
and
Hiroshi Niino Ocean Research Institute, University of Tokyo, Tokyo, Japan

Search for other papers by Hiroshi Niino in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

Polar low dynamics in an idealized atmosphere in which baroclinicity, stratification, and average temperature are varied in the typically observed range is investigated using a 5-km-resolution nonhydrostatic model. The baroclinicity is found to be the most important factor that strongly controls the polar low dynamics.

When the baroclinicity is weak, a small, nearly axisymmetric vortex develops through a cooperative interaction between the vortex flow and cumulus convection. The surface friction promotes the vortex dynamics by transporting the sensible heat and moisture into the vortex center. The vortex development has a strong sensitivity to the initial perturbation.

As the baroclinicity is increased, most of the characteristics of polar low dynamics change smoothly without showing any significant regime shift. The vortex for an intermediate baroclinicity, however, moves northward, which is a unique behavior. This is caused by vortex stretching on the northern side of the vortex where intense convection produces a stronger updraft.

When the baroclinicity is strong, a larger vortex with a comma-shaped cloud pattern develops. The condensational heating, baroclinic conversion from the basic available potential energy, and conversion from the basic kinetic energy through the vertical shear all contribute to the vortex development, which depends little on the initial perturbation. The above relations between baroclinicity and vortex dynamics are proved to be robust in the typically observed range of stratification and average temperature.

* Current affiliation: Center for Climate System Research, University of Tokyo, Chiba, Japan

Corresponding author address: Wataru Yanase, Center for Climate System Research, University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa, Chiba 277-8568, Japan. Email: yanase@ccsr.utokyo.ac.jp

Abstract

Polar low dynamics in an idealized atmosphere in which baroclinicity, stratification, and average temperature are varied in the typically observed range is investigated using a 5-km-resolution nonhydrostatic model. The baroclinicity is found to be the most important factor that strongly controls the polar low dynamics.

When the baroclinicity is weak, a small, nearly axisymmetric vortex develops through a cooperative interaction between the vortex flow and cumulus convection. The surface friction promotes the vortex dynamics by transporting the sensible heat and moisture into the vortex center. The vortex development has a strong sensitivity to the initial perturbation.

As the baroclinicity is increased, most of the characteristics of polar low dynamics change smoothly without showing any significant regime shift. The vortex for an intermediate baroclinicity, however, moves northward, which is a unique behavior. This is caused by vortex stretching on the northern side of the vortex where intense convection produces a stronger updraft.

When the baroclinicity is strong, a larger vortex with a comma-shaped cloud pattern develops. The condensational heating, baroclinic conversion from the basic available potential energy, and conversion from the basic kinetic energy through the vertical shear all contribute to the vortex development, which depends little on the initial perturbation. The above relations between baroclinicity and vortex dynamics are proved to be robust in the typically observed range of stratification and average temperature.

* Current affiliation: Center for Climate System Research, University of Tokyo, Chiba, Japan

Corresponding author address: Wataru Yanase, Center for Climate System Research, University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa, Chiba 277-8568, Japan. Email: yanase@ccsr.utokyo.ac.jp

Save
  • Albright, M. D., and R. J. Reed, 1995: Origin and structure of a numerically simulated polar low over Hudson Bay. Tellus, 47A , 834848.

    • Search Google Scholar
    • Export Citation
  • Bratseth, A. M., 1985: A note on CISK in polar air masses. Tellus, 37A , 403406.

  • Businger, S., and R. J. Reed, 1989: Cyclogenesis in cold air masses. Wea. Forecasting, 4 , 133156.

  • Businger, S., and J-J. Baik, 1991: An arctic hurricane over the Bering Sea. Mon. Wea. Rev., 119 , 22932322.

  • Carleton, A. M., 1985: Satellite climatological aspects of the “polar low” and “instant occlusion.”. Tellus, 37A , 433450.

  • Craig, G., and H. R. Cho, 1988: Cumulus heating CISK in the extratropical atmosphere Part I: Polar lows and comma clouds. J. Atmos. Sci., 45 , 26222640.

    • Search Google Scholar
    • Export Citation
  • Deadorff, J. W., 1980: Stratocumulus-capped mixed layers derived from a three-dimensional model. Bound.-Layer Meteor., 18 , 495527.

  • Duncan, C. N., 1977: A numerical investigation of polar lows. Quart. J. Roy. Meteor. Soc., 103 , 255267.

  • Eady, E. T., 1949: Long waves and cyclone waves. Tellus, 1 , 3352.

  • Emanuel, K. A., and R. Rotunno, 1989: Polar lows as arctic hurricanes. Tellus, 41A , 117.

  • Emanuel, K. A., M. Fantini, and A. J. Thorpe, 1987: Baroclinic instability in an environment of small stability to slantwise moist convection. Part I: Two-dimensional models. J. Atmos. Sci., 44 , 15591573.

    • Search Google Scholar
    • Export Citation
  • Fantini, M., 1999: Linear evolution of baroclinic waves in saturated air. Quart. J. Roy. Meteor. Soc., 125 , 905923.

  • Forbes, G. S., and W. D. Lottes, 1985: Classification of mesoscale vortices in polar airstreams and the influence of the large-scale environment on their evolutions. Tellus, 37A , 132155.

    • Search Google Scholar
    • Export Citation
  • Fu, G., H. Niino, R. Kimura, and T. Kato, 2004: A polar low over the Japan Sea on 21 January 1997. Part I: Observational analysis. Mon. Wea. Rev., 132 , 793814.

    • Search Google Scholar
    • Export Citation
  • Grønås, S., and N. G. Kvamstø, 1995: Numerical simulations of the synoptic conditions and development of Arctic outbreak polar lows. Tellus, 47A , 797814.

    • Search Google Scholar
    • Export Citation
  • Harley, D. G., 1960: Frontal contour analysis of a polar low. Meteor. Mag., 89 , 146147.

  • Harrold, T. W., and K. A. Browning, 1969: The polar low as a baroclinic disturbance. Quart. J. Roy. Meteor. Soc., 95 , 710723.

  • Hart, R. E., 2003: A cyclone phase space derived from thermal wind and thermal asymmetry. Mon. Wea. Rev., 131 , 585615.

  • Heinemann, G., 1990: Mesoscale vortices in the Weddell Sea region (Antarctica). Mon. Wea. Rev., 118 , 779793.

  • Heinemann, G., and C. Claud, 1997: Report of a workshop on “theoretical and observational studies of polar lows” of the European Geophysical Society Polar Lows Working Group. Bull. Amer. Meteor. Soc., 78 , 26432658.

    • Search Google Scholar
    • Export Citation
  • Hewson, T. D., G. C. Craig, and C. Claud, 2000: Evolution and mesoscale structure of a polar low outbreak. Quart. J. Roy. Meteor. Soc., 126 , 10311063.

    • Search Google Scholar
    • Export Citation
  • Jones, S. C., and Coauthors, 2003: The extratropical transition of tropical cyclones: Forecast challenges, current understanding, and future directions. Wea. Forecasting, 18 , 10521092.

    • Search Google Scholar
    • Export Citation
  • Kondo, J., 1975: Air–sea bulk transfer coefficients in diabatic conditions. Bound.-Layer Meteor., 9 , 91112.

  • Kuo, Y-H., and S. Low-Nam, 1990: Prediction of nine explosive cyclones over the western Atlantic ocean with a regional model. Mon. Wea. Rev., 118 , 325.

    • Search Google Scholar
    • Export Citation
  • Lee, T. Y., Y. Y. Park, and Y. L. Lin, 1998: A numerical modeling study of mesoscale cyclogenesis to the east of Korean Peninsula. Mon. Wea. Rev., 126 , 23052329.

    • Search Google Scholar
    • Export Citation
  • Lin, Y. H., R. D. Farley, and H. D. Orville, 1983: Bulk parameterization of the snow field in a cloud model. J. Climate Appl. Meteor., 22 , 10651092.

    • Search Google Scholar
    • Export Citation
  • Mak, M., 1982: On moist quasi-geostrophic baroclinic instability. J. Atmos. Sci., 39 , 20282037.

  • Mansfield, D. A., 1974: Polar lows: the development of baroclinic disturbances in cold air outbreaks. Quart. J. Roy. Meteor. Soc., 100 , 541554.

    • Search Google Scholar
    • Export Citation
  • Montgomery, M. T., and B. F. Farrell, 1992: Polar low dynamics. J. Atmos. Sci., 49 , 24842505.

  • Moore, G. W. K., and P. W. Vachon, 2002: A polar low over the Labrador Sea: Interactions with topography and an upper-level potential vorticity anomaly, and an observation by RADARSAT-1 SAR. Geophys. Res. Lett., 29 .1773, doi:10.1029/2001GL014007.

    • Search Google Scholar
    • Export Citation
  • Murakami, M., 1990: Numerical modeling of dynamical and microphysical evolution of an isolated convective cloud–The 19 July 1981 CCOPE cloud. J. Meteor. Soc. Japan, 68 , 107128.

    • Search Google Scholar
    • Export Citation
  • Nordeng, T. E., and E. A. Rasmussen, 1992: A most beautiful polar low: A case study of a polar low development in the Bear Island region. Tellus, 44A , 8199.

    • Search Google Scholar
    • Export Citation
  • Økland, H., 1987: Heating by organized convection as a source of polar low intensification. Tellus, 39A , 397401.

  • Orlanski, I., 1975: A rational subdivision of scales of atmospheric processes. Bull. Amer. Meteor. Soc., 56 , 527530.

  • Pagowski, M., and G. W. K. Moore, 2001: A numerical study of an extreme cold-air outbreak over the Labrador Sea: Sea ice, air–sea interaction, and development of polar lows. Mon. Wea. Rev., 129 , 4772.

    • Search Google Scholar
    • Export Citation
  • Rasmussen, E., 1979: The polar low as an extratropical CISK disturbance. Quart. J. Roy. Meteor. Soc., 105 , 531549.

  • Rasmussen, E., 1981: An investigation of a polar low with a spiral cloud structure. J. Atmos. Sci., 38 , 17851792.

  • Rasmussen, E., 1985: A case study of a polar low development over the Barents Sea. Tellus, 37A , 407418.

  • Rasmussen, E. A., and J. Turner, 2003: Polar Lows: Mesoscale Weather Systems in the Polar Regions. Cambridge University Press, 612 pp.

  • Reed, R. J., and C. N. Duncan, 1987: Baroclinic instability as a mechanism for the serial development of polar lows: A case study. Tellus, 39A , 376384.

    • Search Google Scholar
    • Export Citation
  • Saito, K., T. Kato, H. Eito, and C. Muroi, 2001: Documentation of the Meteorological Research Institute/Numerical Prediction Division unified nonhydrostatic model. Meteorological Research Institute Tech. Rep. 28, 238 pp.

  • Sardie, J. M., and T. T. Warner, 1983: On the mechanism for the development of polar lows. J. Atmos. Sci., 40 , 869881.

  • Sardie, J. M., and T. T. Warner, 1985: A numerical study of the development mechanism of polar lows. Tellus, 37A , 460477.

  • Shapiro, M. A., L. S. Fedor, and T. Hampel, 1987: Research aircraft measurements of a polar low over the Norwegian Sea. Tellus, 39A , 272306.

    • Search Google Scholar
    • Export Citation
  • Tokioka, T., 1973: A stability study of medium-scale disturbances with inclusion of convective effects. J. Meteor. Soc. Japan, 51 , 110.

    • Search Google Scholar
    • Export Citation
  • Tsuboki, K., and G. Wakahama, 1992: Mesoscale cyclogenesis in winter monsoon air streams: Quasi-geostrophic baroclinic instability as a mechanism of the cyclogenesis off the west coast of Hokkaido Island, Japan. J. Meteor. Soc. Japan, 70 , 7793.

    • Search Google Scholar
    • Export Citation
  • Wang, B., 1987: Another look at CISK in polar oceanic air masses. Tellus, 39A , 179186.

  • Wang, B., and A. Barcilon, 1986: Moist stability of a baroclinic zonal flow with conditionally unstable stratification. J. Atmos. Sci., 43 , 705719.

    • Search Google Scholar
    • Export Citation
  • Yanase, W., and H. Niino, 2004: Structure and energetics of non-geostrophic non-hydrostatic baroclinic instability wave with and without convective heating. J. Meteor. Soc. Japan, 82 , 12611279.

    • Search Google Scholar
    • Export Citation
  • Yanase, W., and H. Niino, 2005: Effects of baroclinicity on the cloud pattern and structure of polar lows: A high-resolution numerical experiment. Geophys. Res. Lett., 32 .L02806, doi:10.1029/2004GL020469.

    • Search Google Scholar
    • Export Citation
  • Yanase, W., H. Niino, and K. Saito, 2002: High-resolution numerical simulation of a polar low. Geophys. Res. Lett., 29 .1658, doi:10.1029/2002GL014736.

    • Search Google Scholar
    • Export Citation
  • Yanase, W., G. Fu, H. Niino, and T. Kato, 2004: A polar low over the Japan Sea on 21 January 1997. Part II: A numerical study. Mon. Wea. Rev., 132 , 15521574.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 294 77 4
PDF Downloads 284 52 2