When the tide comes in on a beach, where does the extra water come from?



Logically I understand that a.) the ocean is HUGE so the amount of incoming water is infitismally tiny compared to the whole, and b.) it is one large body so when the tide comes in there are other beaches where the tides goes out; but are there any other factors to this? Does gravity affect the mass/density of the water somehow that can also attribute to the change?

In: Physics

There is no extra water, it’s just movement of water being pulled towards the external gravity source. ie the moon. So water elsewhere is going down…low tide.

Imagine the moon as a magnet for water. Wherever he is, water forms a mountain. Literally. So on the opposite site there is a valley. Flood and ebb.

Generally it comes from a few dozen or hundred meters off shore depending on the geography. Meanwhile on the other side of the ocean water moves away from shore by a few dozen or hundred meters, and as a whole the entire ocean gets shoved slightly east or slightly west. The center of the ocean may move slightly east or west by a few cm.

This is due to the modest gravitational pull off the sun and the moon.

Large lakes also experience tides but it tends to be on the order of a cm or two.

The best analogy I can think of is sloshing water back and forth in your bathtub. Water on the center of the tub only moves back and forth a few cm, while at either end the moving water piles up forming a wave that rises and falls much more dramatically.

Think of the oceans as a giant water bed, you put something heavy on one end and it pushes the opposite end up.
In the case of the ocean it’s actually a pulling action by the moons gravity that causes the water to swell.

I dont think its extra water. Its just the water itself being pushed much further than before. Water doesnt increase or decrease in the ocean it just gets pushed harder or lighter