Abstract
The evolution and structure of the steady state of an idealized nocturnal drainage flow over a large uniformly-sloping surface are studied using a nonstationary model with a height-dependent eddy diffusivity profile and a specified surface cooling rate. The predicted mean velocity and temperature profiles are compared with Prandtl's stationary analytical solutions based on the assumption of a constant eddy diffusivity in the drainage layer. The effects of important physical parameters, such as the slope angle, surface cooling, atmospheric stability, and surface roughness, on the steady drainage flow are investigated.
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Brost, R. A. and Wyngaard, J. C.: 1978, ‘A Model Study of the Stably Stratified Planetary Boundary Layer’. J. Atmos. Sci. 35, 1427–1440.
Businger, J. A., Wyngaard, J. C., Izumi, Y., and Bradley, E. F.: 1971, ‘Flux-Profile Relations in the Atmospheric Surface Layer’. J. Atmos. Sci. 28, 181–189.
Defant, F.: 1949, ‘Zur Theorie der Hangwinde, nebst Bemerkungen zur Theorie der Berg- und Talwinde’. Arch. Meteor. Geophys. Biokl. A1, Springer-Verlag, 421–450.
Defant, F.: 1951, ‘Local Winds’. Compendum of Meteorology T. F. Malone, ed., Amer. Meteor. Soc., Boston, 655–672.
Delage, Y.: 1974, ‘A Numerical Study of the Nocturnal Atmospheric Boundary Layer’. Quart. J. Roy. Meteorol. Soc. 100, 351–364.
Ellison, T. H. and Turner, J. S.: 1959, ‘Turbulent Entrainment in Stratified Flows’, J. Fluid Mech. 6, 423–448.
Gutman, L. N.: 1972, Introduction to the Nonlinear Theory of Mesoscale Meteorological Processes. TT 71–50132, available from NTIS, Springfield, Va. 22151, 224 pp.
Lettau, H. H.: 1966, ‘A Case Study of Katabatic Flow on the South Polar Plateau’. Studies in Antarctic Meteorology M. J. Rubin, Ed., Antarctic Res. Ser. 9, Amer. Geophys. Union, 1–11.
Manins, P. C. and Sawford, B. L.: 1979, ‘A Model of Katabatic Winds’. J. Atmos. Sci. 36, 619–630.
Nieuwstadt, F. T. M. and Driedonks, A. G. M.: 1979, ‘The Nocturnal Boundary Layer: A Case Study Compared with Model Calculations’. J. Appl. Meteorol. 18, 1397–1405.
Prandtl, L.: 1942, Führer durch die Strömungslehre, Vieweg u. Sohn, Braunschweig, 373–375. Available in English as Essentials of Fluid Dynamics, Hafner Publishing Co., New York, 1952, 452 pp.
Rao, K. S. and Snodgrass, H. F.: 1979, ‘Modeling the Nocturnal Drainage Flows. Part I’. ATDL Contribution File No. 79/5, NOAA-ATDL, Oak Ridge, Tn., 54 pp.
Thyer, N. H.: 1966, ‘A Theoretical Explanation of Mountain and Valley Winds by a Numerical Method’. Arch. Meteor. Geophys. Bioklim., A15, 318–348.
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Affiliated with Oak Ridge Associated Universities (ORAU).
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Rao, K.S., Snodgrass, H.F. A nonstationary nocturnal drainage flow model. Boundary-Layer Meteorol 20, 309–320 (1981). https://doi.org/10.1007/BF00121375
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DOI: https://doi.org/10.1007/BF00121375