What term refers to the periodic rise and fall of sea levels?

The term that refers to the periodic rise and fall of sea levels is "tides." Tides are caused primarily by the gravitational forces exerted by the Moon and the Sun on Earth's oceans. As the Earth rotates, different areas of the planet experience these gravitational pulls, leading to the cyclical rising and falling of sea levels known as tidal movements.

Each tide has a predictable pattern, occurring roughly every six hours for high and low tides, influenced by the position of the Moon relative to Earth. Understanding tides is essential for various fields, including marine biology, navigation, and coastal management, as they affect ocean currents, marine ecosystems, and human activities along coastlines.