Scott D. Hansen
Kenneth E. Gilbert
Appl. Res. Lab. and the Graduate Program in Acoust., Penn State Univ., P. O. Box 30, State College, PA 16804
During the Joint Acoustic Propagation Experiment conducted at the White Sands Missile Range in the summer of 1991, wind speed measurements were made on two 32-m-high towers. The vector wind speed was sampled continuously at 10 Hz for periods of up to 2 h. The power spectra for wind speed fluctuations (turbulence spectra) have been computed at heights of 2, 4, 8, 16, and 32 m. For a given sample length, the spectra are nearly the same at all heights. At all heights, however, there is significant sensitivity to the length of the sampling period. The meteorological reasons for the sensitivity are discussed. In addition, selected acoustic propagation calculations are presented to demonstrate the influence of the different spectra on acoustic propagation. [Work supported by the Army Research Laboratory.]