On the relationship between the gradient and the bulk Richardson number for the atmospheric surface layer
Semi-empirical formulations which have been proposed to describe the wind and potential temperature profiles are used to derive relationships between the gradient Richardson number, Ri, the finite-difference layer Richardson number, Rib, the surface layer Richardson number, Ris, and the bulk Richardson number,B, through the atmospheric surface layer. The theoretical analysis for stable conditions indicates that Ri (z 3)=Rib, wherez 3=(z 2−z 1)/ln(z 2/z 1), andz 2;z 1=upper and lower levels at which temperature and wind speed are specified. It is also found that, during stable conditions, the wind profile power law exponent,p, is computed at the heightz 3, instead of the widely used geometric mean height,z m, between top (z 2) and bottom (z 1) of the layer considered.
Unable to display preview. Download preview PDF.
- N. M. Zoumakis andA. G. Kelessis:Nuovo Cimento C,14, 587 (1991).Google Scholar
- N. M. Zoumakis andA. G. Kelessis:The dependence of the bulk Richardson number on stability in the surface layer, to be published inBoundary-Layer Meteorol.Google Scholar
- H. Lettau andB. Davidson:Exploring the Atmosphere's Firts Mile (Pergamon Press, Inc., New York, N.Y., 1957).Google Scholar
- N. M. Zoumakis andA. G. Kelessis:On the theoretical variation of the Monin-Obukhov stability parameter as a function of the bulk Richardson number, submitted toJ. Appl. Meteorol.Google Scholar
- H. A. Panofsky andB. Prasad:Int. J. Air Water Pollut.,9, 419 (1965).Google Scholar
- H. A. Panofsky andJ. A. Dutton:Atmospheric Turbulence (Wiley and Sons, 1983), p. 397.Google Scholar