Report on Research to Investigate Atmospheric Infrasonic Pressure Variations

摘要

The pressure variations of the atmosphere at White Sands Missile Range, New Mexico, were recorded using a solion infrasonic microphone array. The dimensions of the square array were 10,000 ft per side. The solion infrasonic microphone monitored data in the pressure range of 0.1 to 500 dyn/sq cm and in the frequency region of 0.033 to 50 cps. Measurements were made during high winds (20 to 30 knots) and very low winds (0 to 4 knots). The statistical nature of the infrasonic atmospheric pressure data obtained is presented by the use of probability density functions, autocorrelation functions, cross-correlation functions, power spectra, and cross-power spectra. These results indicate that the high-wind infrasound was caused by statistically independent eddies. The eddies were created by large scale atmospheric motions associated with the high winds. The power spectra afforded a means by which relative eddy size estimates were calculated for the high-wind infrasound. The statistical properties of the low-wind data indicate that the low-wind infrasound was probably radiated by upper atmospheric turbulence. (Author)