Effects of Changes in Vegetation on Mesonet Wind Speed Measurements

The Oklahoma Mesonet provides observations of numerous meteorological quantities at 121 sites. Quality assurance is a focal point of the measurement network, with many criteria used to ensure the accuracy of the data the Mesonet provides. Changes in vegetation around these sites is one aspect that is hard to control, manage, and quantify. Both growth and reduction of vegetation have a significant effect on wind speed observations at Mesonet sites. At sites where plant life was removed or introduced, mean wind speeds increased or decreased respectively. Wind speeds from directions where changes in vegetation occurred upwind saw the greatest changes in mean values. In addition, the effects of drag on the wind speed were found to increase from west to east. Roughness characteristics, along with detailed descriptions of microscale obstructions at Mesonet sites, would help to increase accuracy and consistency of wind speed measurements.