shock wave, wave formed of a zone of extremely high pressure within a fluid, especially the atmosphere, that propagates through the fluid at a speed in excess of the speed of sound. A shock wave is caused by the sudden, violent disturbance of a fluid, such as that created by a powerful explosion or by the supersonic flow of the fluid over a solid object. Propagating from the point of the disturbance, a shock wave carries energy and can have destructive effects as it impinges on solid objects. A shock wave decays rapidly with increasing distance from its point of origin, gradually changing into an ordinary sound wave. Continuous shock waves, such as those produced by supersonic aircraft, are of particular concern as they tend to recur along regular routes. Even after they have decayed into sound waves, thus losing their destructive force, they remain capable of creating noise levels harmful to human beings and animals.