Approximate Solutions For The Obukhov Length And The Surface Fluxes In Terms Of Bulk Richardson Numbers

Simple analytic approximate solutions arepresented for the set of equations that follows fromthe Monin–Obukhov flux-profile relationships using thestability functions of Dyer (unstable case) andBeljaars–Holtslag (stable case). Several publicationsare devoted to the same subject, however the currentapproach contains some new features, namely: (a) itappears to be more accurate for unstable situationsand (b) it applies also to the general case where windspeed (u) and potential temperature(θ) are given at different levels. In order toillustrate the accuracy of the approach a comparisonwith the actual solutions is presented for someselected combinations of θ and u levelstypical for various practical applications.

[1]  A. Holtslag,et al.  Applied Modeling of the Nighttime Surface Energy Balance over Land , 1988 .

[2]  S. Emori,et al.  A simple extension of the Louis method for rough surface layer modelling , 1995 .

[3]  Alan K. Betts,et al.  Estimation of effective roughness length for heat and momentum from FIFE data , 1993 .

[4]  J. Howell,et al.  Surface-Layer Fluxes in Stable Conditions , 1999 .

[5]  J. Garratt.  The Atmospheric Boundary Layer , 1992 .

[6]  J. Goutorbe.  A Critical Assessment of the Samer Network Accuracy , 1991 .

[7]  J. Launiainen.  Derivation of the relationship between the Obukhov stability parameter and the bulk Richardson number for flux-profile studies , 1995 .

[8]  Yuheng Song.  An Improvement of the Louis Scheme for the Surface Layer in an Atmospheric Modelling System , 1998 .

[9]  H. D. Bruin.  A note on Businger's derivation of Nondimensional Wind and Temperature Profiles under unstable Conditions , 1999 .

[10]  Albert A. M. Holtslag,et al.  Simulation of Surface Fluxes and Boundary Layer Development over the Pine Forest in HAPEX-MOBILHY , 1996 .

[11]  J. Louis.  A parametric model of vertical eddy fluxes in the atmosphere , 1979 .

[12]  H. Mohr,et al.  A Critical Assessment , 1985, The Federal Estate Tax.

[13]  A. Holtslag,et al.  On the bulk parameterization of surface fluxes for various conditions and parameter ranges , 1997 .

[14]  Albert A. M. Holtslag,et al.  Flux Parameterization over Land Surfaces for Atmospheric Models , 1991 .

[15]  S. Derbyshire.  Stable Boundary-Layer Modelling: Established Approaches and Beyond , 1999 .

[16]  Daewon W. Byun,et al.  On the Analytical Solutions of Flux-Profile Relationships for the Atmospheric Surface Layer , 1990 .

[17]  A. Dyer.  A review of flux-profile relationships , 1974 .

[18]  Emmanuel Guilloteau,et al.  Optimized Computation of Transfer Coefficients in Surface Layer with Different Momentum and Heat Roughness Lengths , 1998 .

[19]  Larry Mahrt,et al.  Stratified Atmospheric Boundary Layers , 1999 .

[20]  On the role of roughness lengths in flux parameterizations of boundary-layer models , 1996 .