Determination of the Power-Law Wind Profile Exponent on a Tropical Coast

Abstract

Hourly measurements of temperature and wind speed (at 10 and 33 m) for a one-year period were made on the flat south coast of St. Croix, U.S. Virgin Islands. Values of the exponent p used in the power-law wind profile were obtained by applying criteria of Golder's (1972) nomogram, the U.S. Nuclear Regulatory Commission's (1974) temperature difference method, and Sedefian's (1980) formulation. It was found that p ranges from 0.15 for stability class A to >0.40 for class F. Thus the familiar 1/7 power law will not be useful for a tropical coast. Since expected values of p as determined from Sedefian's nomogram were in good agreement with the observations, it is recommended for use in a tropical environment.