Open AccessFriction velocity estimation using a 2D sonic anemometer in coastal zones
Author(s) -
Bernardo Figueroa-Espinoza,
Zulia Mayari Sánchez-Mejía,
J. M. Uuh-Sonda,
Paulo Salles,
Luis A. Méndez-Barroso,
H. A. Gutiérrez-Jurado
Publication year - 2022
Publication title -
atmósfera
Language(s) - English
Resource type - Journals
eISSN - 2395-8812
pISSN - 0187-6236
DOI - 10.20937/atm.52960
Subject(s) - anemometer , wind speed , atmospheric instability , turbulence , shear velocity , environmental science , geology , meteorology , sensitivity (control systems) , atmospheric sciences , geodesy , physics , oceanography , engineering , electronic engineering
Friction velocity (u*) is an important velocity scale used in the study of engineering and geophysical flows. The widespread use of 2D sonic anemometers in modern meteorological stations makes the estimation of u* from just the horizontal components of the velocity a very attractive possibility. The presence of different wind regimes (such as sea breezes in or near coastal zones) causes the turbulent parameters to be dependent on the wind direction. Additionally, u* depends on atmospheric stability, whch makes the estimation of u* from 2D measurements very difficult. A simple expression is proposed, and then tested with data from six independent experiments located in coastal zones. The results show that it is possible to estimate friction velocity from 2D measurements using the turbulence intensity as a proxy for u*, reducing substantially the sensitivity to the wind direction or atmospheric stability, with small root mean squared errors (0.06 < RMSE < 0.097) and high correlation coefficients (0.77 < r2 < 0.95).