Boundary-Layer Meteorology

, Volume 36, Issue 4, pp 371–394 | Cite as

Thermal asymmetry and cross-valley circulation in a small alpine valley

  • Barbara Hennemuth
Article

Abstract

Wind observations from a small Alpine valley are used to investigate the problem of cross-valley winds. The observed daytime windfield is a superposition of dynamically and thermally forced cross-winds. Prevailing cross-winds above the valley result in a recirculation cell above the lee slope. The return flow is strengthened or weakened by thermal effects which induce a wind that blows from the shaded to the sunny side of the valley. The reaction time of the thermally induced cross-winds is only 4 min. The horizontal and vertical motions of the cross-valley circulation transport heat in such a way that the insolation differences between the two sides of the valley are nearly equalized.

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References

  1. Bell, R. C. and Thompson, R. O. R. Y.: 1980, ‘Valley Ventilation by Cross Winds’, J. Fluid Mech. 96, 757–767.Google Scholar
  2. Brehm, M. and Freytag, C.: 1982, ‘Erosion of the Night-Time Thermal Circulation in an Alpine Valley’, Arch. Met. Geoph. Biocl. B31, 331–352.Google Scholar
  3. Brühl, Chr. and Zdunkowski, W.: 1983, ‘An Approximate Calculation Method for Parallel and Diffuse Solar Irradiances on Inclined Surfaces in the Presence of Obstructing Mountains or Buildings’, Arch. Met. Geoph. Biocl. B32, 111–129.Google Scholar
  4. Defant, F.: 1949, ‘Zur Theorie der Hangwinde nebst Bemerkungen zur Theorie der Berg- und Talwinde’, Arch. Met. Geoph. Biocl. A1, 421–450 (English translation: Whiteman, C. D. and E. Dreiseitl: 1984, Alpine Meteorology: Translations of Selected Contributions by A. Wagner, E. Ekhart, and F. Defant, ASCOT-84–3/PNL-5141, June 1984, Pacific Northwest Laboratory, Richland, Washington, 121 pp.).Google Scholar
  5. Egger, J.: 1981, ‘Thermally Forced Circulations in a Valley’, Geophys. Astrophys. Fluid Dynamics 17, 255–279.Google Scholar
  6. Freytag, C.: 1985, ‘MERKUR-Results: Aspects of the Temperature Field and the Energy Budget in a Large Alpine Valley During Mountain and Valley Wind’, Contr. Atm. Phys. 58, 458–476.Google Scholar
  7. Gleeson, T. A.: 1951, ‘On the Theory of Cross-Valley Winds Arising from Differential Heating of the Slopes’, J. Meteorol. 8, 398–405.Google Scholar
  8. Hennemuth, B.: 1985, ‘Temperature Field and Energy Budget of a Small Alpine Valley’, Contr. Atmosph. Phys. 58, 545–559.Google Scholar
  9. Hennemuth, B.: 1986, ‘Heating of a Small Alpine Valley’, Meteorol. Atm. Phys. 35 (in press).Google Scholar
  10. Hennemuth, B. and Köhler, U.: 1984, ‘Estimation of the Energy Balance of the Dischma Valley’, Arch. Meteorol. Geophys. Biocl. B34, 97–119.Google Scholar
  11. Hennemuth, B. and Schmidt, H.: 1985, ‘Wind Phenomena in the Dischma Valley during DISKUS’, Arch. Meteorol. Geophys. Biocl. B35, 361–387.Google Scholar
  12. MacHattie, L. B.: 1968, ‘Kananaskis Valley Winds in Summer’, J. Appl. Meteorol. 7, 348–352.Google Scholar
  13. Moll, E.: 1935, ‘Aerologische Untersuchungen periodischer Gebirgswinde in V-förmigen Alpentälern’, Beitr. Phys. d. Atmosph. 22, 177–199.Google Scholar
  14. Nickus, U. and Vergeiner, J.: 1984, ‘The Thermal Structure of the Inn Valley Atmosphere’, Arch. Meteorol. Geophys. Biocl. A33, 199–215.Google Scholar
  15. Reiter, R., Müller, H., Sladkovic, R., and Munzert, K.: 1983, ‘Aerologische Untersuchungen der tagesperiodischen Gebirgswinde unter besonderer Berücksichtigung des Windfeldes im Talquerschnitt’, Meteorol. Rdschau 36, 225–242.Google Scholar
  16. Sturman, A. P., Fitzsimons, S. J., and Holland, L. M.: 1985, ‘Local Winds in the Southern Alps, New Zealand’, J. Climatol. 5, 145–160.Google Scholar
  17. Tampieri, F. and Hunt, J. C. R.: 1985, ‘Two-Dimensional Stratified Fluid Flow over Valleys: Linear Theory and Laboratory Investigation’, Boundary-Layer Meteorol. 32, 257–279.Google Scholar
  18. Tang, W.: 1976, ‘Theoretical Study of Cross-Valley Wind Circulation’, Arch. Meteorol. Geophys. Biocl. A25, 1–18.Google Scholar
  19. Tang, W. and Peng, L.: 1983, ‘A Numerical Model of Slopewind Circulation Regimes in a V-shaped Valley’, Arch. Meteorol. Geophys. Biocl. B32, 361–380.Google Scholar
  20. Urfer, Ch.: 1967, ‘Zeitliche Gesetzmäβigkeiten des Berg- und Talwindes’, Veröff. Schweiz. Met. Z.-anstatt 4, 246–252.Google Scholar
  21. Urfer-Henneberger, Ch.: 1970, ‘Neuere Beobachtungen Über die Entwicklung des Schönwetterwindsystems in einem V-förmigen Alpental (Dischmatal bei Davos)’, Arch. Meteorol. Geophys. Biocl. B18, 21–42.Google Scholar
  22. Vergeiner, J.: 1982, ‘Eine energetische Theorie der Hangwinde’, Ann. Meteorol. NF 19, 189–191.Google Scholar
  23. Whiteman, C. D.: 1985, ‘Cross-Valley Structure of the Valley Atmosphere During the Temperature Inversion Breakup Period’, J. Climate Appl. Meteorol. (submitted).Google Scholar
  24. Yoshino, M. M.: 1975, Climate in a Small Area, University of Tokyo Press, Tokyo.Google Scholar

Copyright information

© D. Reidel Publishing Company 1986

Authors and Affiliations

  • Barbara Hennemuth
    • 1
  1. 1.Meteorologisches Institut, Universität MünchenMünchenF.R.G.

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