Boundary-Layer Meteorology

, Volume 49, Issue 3, pp 265–293 | Cite as

Observation and modeling of thermally induced upslope flow

  • Tsuneo Kuwagata
  • Junsei Kondo
Article

Abstract

Thermally induced upslope flows were observed on several slopes and in valleys, and a simple one-layer model of upslope flow was developed. In this model, the thickness and speed of upslope flow are expressed in terms of sensible heat flux from the slope surface, drag coefficient of the slope surface, slope steepness and stability of the ambient atmosphere. Model results compare favorably with the observations.

The development process in the upslope direction of a steady upslope flow was investigated with this model. A steadily developing state in the upslope direction is expressed by the dimensionless equations together with a unique parameter associated with momentum advection. The vertical distance of the slope required for well-developed upslope flow has a minimum value for a moderate slope steepness, but increases monotonously with decreasing ambient stability. The effect of unsteadiness on upslope flow was also investigated. The transient time required to reach a steady state becomes shorter with increasing ambient stability and slope steepness.

Keywords

Atmosphere Steady State Heat Flux Development Process Advection 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Atkinson, B. W.: 1981, Meso-scale Atmospheric Circulations, Academic Press, New York, 495 pp.Google Scholar
  2. Bader, D. C. and McKee, T. B.: 1983, ‘Dynamic Model of the Morning Boundary Layer Development in Deep Mountain Valley’, J. Climate Appl. Meteorol. 22, 341–351.Google Scholar
  3. Banta, R. M.: 1986, ‘Daytime Boundary-layer Evolution over Mountainous Terrain. Part II: Numerical Studies of Upslope Flow Duration’, Mon. Weather Rev. 114, 1112–1130.Google Scholar
  4. Banta, R. and Cotton, W. R.: 1981, ‘An Analysis of the Structure of Local Wind Systems in a Broad Mountain Basin’, J. Appl. Meteorol. 20, 1255–1266.Google Scholar
  5. Brutsaert, W. H.: 1982, Evaporation into the Atmosphere, D. Reidel Publ. Co., Dordrecht, Holland, 299 pp.Google Scholar
  6. Jeffreys, H.: 1922, ‘On the Dynamics of the Wind’, Quart. J. Roy. Meteorol. Soc. 48, 29–47.Google Scholar
  7. Kondo, J. and Kawanaka, A.: 1986, ‘Numerical Study of the Bulk Heat Transfer Coefficient for a Variety of Vegetation Type and Densities’, Boundary-Layer Meteorol. 37, 285–296.Google Scholar
  8. Kondo, J., Kuwagata, T., and Haginoya, S.: 1989, ‘Heat Budget Analysis of Nocturnal Cooling and Daytime Heating in a Basin’, J. Atmos. Sci. 46, 2917–2933.Google Scholar
  9. Kondo, J. and Sato, T.: 1988, ‘A Simple Model of Drainage Flow on a Slope’, Boundary-Layer Meteorol. 43, 103–123.Google Scholar
  10. Kondo, J. and Yamazawa, H.: 1986, ‘Aerodynamic Roughness over an Inhomogeneous Ground Surface’, Boundary-Layer Meteorol. 35, 331–348.Google Scholar
  11. Mahrt, L.: 1982, ‘Momentum Balance of Gravity Flows’, J. Atmos. Sci. 39, 2701–2711.Google Scholar
  12. Manins, P. C. and Sawford, B. L.: 1979, ‘A Model of Kabatic Wind’, J. Atmos. Sci. 36, 619–630.Google Scholar
  13. McNider, R. T. and Pielke, R. A.: 1984, ‘Numerical Simulation of Slope and Mountain Flows’, J. Climate Appl. Meteorol. 23, 1441–1453.Google Scholar
  14. Moore, G. E., Daly, C., Liu, M., and Huang, S.: 1987, ‘Modeling of Mountain-valley Wind Fields in the Southern San Joaquin Valley, California’, J. Climate Appl. Meteorol. 26, 1230–1242.Google Scholar
  15. Prandtl, L.: 1942, Füther durch die Strömungslehre, Braunschweig Vieweg und Sohn.Google Scholar
  16. Rao, P. K., and Snodgrass, H. F.: 1981, ‘A Nonstationary Nocturnal Drainage Flow Model’, Boundary-Layer Meteorol. 20, 309–320.Google Scholar
  17. Sato, T. and Kondo, J.: 1988, ‘A Simple Model of Drainage Flow in a Valley’, Boundary-Layer Meteorol. 45, 355–369.Google Scholar
  18. Segal, M., Ookouchi, Y., and Pielke, R. A.: 1987, ‘On the Effects of Steep Slope Orientation on the Intensity of Day-time Upslope Flow’, J. Atmos. Sci. 44, 3587–3592.Google Scholar
  19. Shirasaki, K.: 1986, ‘A Numerical Study of Local Circulation as Influenced by Clouds’, Papers in Meteorology and Geophysics 37, 169–192.Google Scholar
  20. Shirasaki, K., Toya, T., Kitade, T., and Suzuki, M.: 1984, ‘Observation of Slope Flow over Mountainous Terrain. Part 1’, Proceedings of the 1984 Spring Convention Japan Meteorol. Soc. 45, 217 (in Japanese).Google Scholar
  21. Wagner, A.: 1938, ‘Theorie und Beobachtungen der periodischen Gebirgswinde’, Beitr. Geophys. (Leipzig) 52, 408–449.Google Scholar
  22. Wenger, R.: 1923, ‘Zur theorie der berg- und talwinde’, Met. Z. 40, 193–204.Google Scholar
  23. Whiteman, C. D.: 1982, ‘Breakup of Temperature Inversions in Deep Mountain Valleys: Part I. Observations’, J. Appl. Meteorol. 21, 270–289.Google Scholar
  24. Ye, Z. J., Segal, M. and Pielke, R. A.: 1987, ‘Effects of Atmospheric Thermal Stability and Slope Steepness on the Development of Day-time Thermally Induced Upslope Flow’, J. Atmos. Sci. 44, 3341–3354.Google Scholar

Copyright information

© Kluwer Academic Publishers 1989

Authors and Affiliations

  • Tsuneo Kuwagata
    • 1
  • Junsei Kondo
    • 1
  1. 1.Geophysical Institute, Tohoku UniversitySendaiJapan

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