Crosswind effects on acoustic propagation

Ray theory says that a ray moving in a crosswind will drift out of the plane of propagation, and that this effect can be significant with high windspeeds and over long propagation distances. White and Li [Michael J. White and Y. L. Li, J. Acoust. Soc. Am. 92, 2405 (A) (1992)] and Wilson [D. Keith Wilson, J. Acoust. Soc. Am. 92, 2405 (A) (1992)] developed two‐dimensional fast‐field programs (2DFFPs) to calculate the sound pressure levels of windy atmospheres. They reported that crosswind effects were negligible for the cases they considered and that a one‐dimensional stationary phase solution yields accurate results. Ray analysis of the two‐dimensional phase space used in the 2DFFP indicates that there is a small region that contributes significantly to the sound level. In the presence of a crosswind, the one‐dimensional stationary phase approximation does not include all of this region. 2DFFP calculations for realistic windspeeds that show crosswind drift are presented, and the 2DFFP calculations are comp...