Which characteristic of waves does NOT commonly change as they travel from deep water to shallow water?

The wave period is the time it takes for one complete wave cycle to pass a given point. This characteristic is primarily determined by the wind speed, the duration of the wind, and the fetch (the distance over which the wind blows). As waves travel from deep water to shallow water, they undergo certain transformations due to the interaction with the seabed.

In shallow water, waves will change in height, speed, and wavelength. This is because as waves enter shallower depths, the decrease in water depth causes the wave to slow down and the wavelength to shorten, leading to an increase in wave height due to energy conservation. However, the wave period remains unchanged because it is a function of the wave generation conditions, not the water depth. Thus, among the characteristics listed, the wave period is the only one that does not commonly change as waves transition from deep water to shallow water.