This type of water transition or change in phase of matter is known as FREEZING.
Water has molecules that are free flowing and have the ability to collide and bounce against each other, that's why it has that kind of characteristic that it takes the shape of its container.
When these molecules are exposed to lower or colder temperatures, the molecules tend to vibrate and get attracted towards each other, creating a semi-solid or completely solid material. In this example, liquid turned into frost because of the low temperature present within the environment.
If waves continuously crash down on the land over time, the shore begins to erode because of the amount of pressure constantly pushes down on it, which can cause the shore to eventually wear down.
