Translations:AY Honors/Oceans/Answer Key/74/en
From Pathfinder Wiki
As the earth rotates, a given point on the earth (such as a seashore) gets nearer and nearer to the moon until it is as close to the moon as it will get on that day. When this happens, the gravitational pull on the ocean is at its greatest (since the force of gravity increases as distance decreases). Since the ocean is closer to the moon than the center of the earth, it pulls harder on the ocean, and this causes the ocean to rise up. That causes a high tide.
