1. Once a wave has been generated its speed may change, but its period does not as this characteristic is determined by the generating force. 2. Deep-water waves (waves of oscillation) a. Deep-water waves occur where the water is deeper than 1/2 the wavelength of the waves. b. In deep water the velocity of a wave is a function of wavelength. c. Waves are created in storm centers or by the steady winds of the westerlies and trades.