METHOD FOR ESTIMATION OF SURFACE-ROUGHNESS AND SIMILARITY FUNCTION OFWIND-SPEED VERTICAL PROFILE

This study is aimed at identifying and refining a method suitable to e stimate the surface roughness length (Z(o)) and the universal similari ty function of the wind speed profile (Psi(M)) based on ultrasonic ane mometer measurements carried out at only one measurement height. This method does not require experimental knowledge of wind speed vertical profiles. It permits the use of experimental data obtained from a sing le sonic anemometer placed in the surface layer in any stability condi tion, thereby simplifying experimental campaigns and cost reduction. I n a fixed station equipped with a sonic anemometer, it is also possibl e to obtain a periodic estimate of z(o) without additional ad hoc expe rimental campaigns; thus one can correlate the evolution of this param eter to changes that could be found over the area being studied. To pr ove its feasibility, the method was applied to data obtained in an exp erimental campaign carried out in Mexico near the northeast side of Me xico City. An ultrasonic anemometer operating at an altitude of 10 m a bove surface level was used. The method supplied positive results, the reby confirming its operative usefulness.