Averaging a wave characteristic over one full cycle. Buoyant oscillations in the form of gravity waves can exist in the atmosphere and ocean, and these oscillations can transport momentum and energy. However, the amount of transport often oscillates too, so an instantaneous measure of these momentum or energy fluxes would not be representative. A better value is obtained by measuring the transport at many closely spaced intervals during the passage of any one wave, and then finding the mean value of the measurements.