From December 1995 until January 1997 measurements of turbulent momentum and sensible heat fluxes were conducted at 20, 100, and 180 m height at the Cabauw tower. In combination with the continuous measurements of profiles of mean wind speed and temperature taken at 6 levels from 10 to 200 m at the tower, flux-profiles relationships at the three levels can be examined. In this paper, only data from the summer period (May-October) are discussed.
As a result of nearby roughness transitions, kinks are found in the wind speed profiles in the surface layer. Also strongly curved profiles are found as a results of changing stability with height. These stability changes are associated with heat and momentum flux divergence, as can be shown from the turbulence measurements. As a result, it is not possible to extrapolate the velocity or temperature profile downwards, using wind speed and momentum flux, or temperature and heat flux observations from elevated levels together with the usual flux-profile relationships for the surface layer. However, standard flux-profile relationships do still hold when these are calculated using local fluxes and profiles, regardless the homogeneity or heterogeneity of the upstream terrain