Deriving Flux-profile Relationships to Improve Wind Speed Estimates at Mountain Ridge-tops

Accurate representation of vertical wind and temperature profiles in the atmospheric surface layer (approximately the lowest 10% of the boundary layer) is of high importance to the wind-energy community. Flux-profile relationships based on Monin-Obukhov Similarity Theory (MOST) form the basis of parameterizing wind and temperature profiles in this region of the atmosphere. There have been several studies on the applicability of MOST relationships over uniform terrain, while studies over complex terrain are limited.

Wind speed and temperature data from a meteorological mast located on a mountain ridge-top in the complex terrain of northern British Columbia, Canada, are used to derive new empirical relationships for the non-dimensional wind shear and temperature gradient in different stability regimes. These will be evaluated against traditional MOST relationships using data from two other independent meteorological masts.  Preliminary results suggest that the largest improvement over other flux-profile relationships occurs during stable regimes, where previously winds have been overestimated.