ISSN:
1573-1472
Keywords:
Roughness sublayer
;
Wind profile
;
Profile function
;
Coniferous forest
;
Large roughness
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Physics
Notes:
Abstract Wind velocity and temperature measurements from a 200 m tower, locatedin a forest near Karlsruhe were used to investigatethe modified profile function of the wind velocity in theroughness sublayer. To avoid determination of the friction velocity we introduced analternative analysis with the expression $$F_m^{\text{*}} = z\frac{\partial }{{\partial z}}\ln \left( {\frac{{\kappa z}}{{u_* }}\frac{{\partial u}}{{\partial z}}} \right)$$ instead of $$\Phi _m^{\text{*}} = \frac{{\kappa z}}{{u_* }}\frac{{\partial u}}{{\partial z}}.$$ From the observed Fm* profiles we evaluated the profile function Φ m*. The wind profiles observed under neutral conditions were well representedby a modified non-dimensional profile function with physically based boundary values at the top and at the bottom of theroughness sublayer. The results of our analysis can be used to take into consideration themomentum exchange between the atmosphere and a forest in mesoscaleatmospheric models in a refined way.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1000444911103
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