Variation of the speed of sound in air with humidity and temperature

This paper describes the influence of humidity on the speed of sound in standard atmospheric air at various temperatures. The prediction is based on theoretical and experimental data obtained for the variation of the ratio of specific heats, γ, in humid air. Over a temperature range from 0°–30° Celsius, the maximum uncertainty in the sound speed ratio c_h/c₀, is estimated to be about 400 ppm. Comparison is made with known experimental measurements and theoretical data.