Which phenomenon is caused by the gravitational pull of the moon and sun, resulting in predictable rise and fall of sea levels?

The phenomenon that causes the predictable rise and fall of sea levels due to the gravitational pull of the moon and the sun is known as tides. Tides result from the gravitational attraction that the moon exerts on the Earth, which causes the water in the oceans to bulge out in the direction of the moon. This creates high tides in those locations. Conversely, on the side of the Earth opposite the moon, there is also a high tide due to the centrifugal force caused by the Earth-moon system's rotation. The sun also influences tides, although to a lesser extent than the moon.

Understanding tides is crucial in oceanography, as they impact marine navigation, coastal ecosystems, and the behavior of various marine organisms. They operate on a predictable cycle, usually occurring twice a day in most locations, which allows for anticipation of when high and low tides will occur.