Solitary waves in the lower atmosphere

Abstract

Solitary waves are of intense interest in the physical and mathematical sciences¹. These nonlinear waves often seem to have a primary role in the asymptotic description of propagating disturbances in inland lakes and coastal waters^2–4, in the thermocline of the open sea⁵ and in the lower atmosphere^6,7. We present here new acoustic sounder observations of complex tropospheric solitary-wave disturbances at Tennant Creek in the arid interior of Australia (Fig. 1), a description and interpretation of a new type of visible wave phenomena over northern Australia which appear as thin propagating cumulus cloud lines, and a discussion of observations at Burketown on the Gulf of Carpentaria of a new class of low-altitude propagating solitary-wave roll clouds which originate to the south. These observations, when correlated with observations at Tennant Creek, indicate that solitary-wave-generating disturbances in the form of internal bores^8,9 propagate over large distances.