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How do you call the areas where the ocean stick out at the sides of the earth?
Question Date: 2018-03-16
Answer 1:

Thank you for your question, “How do you call the areas where the ocean stick out at the sides of the earth?” There are a few different situations were land, water, and Earth stick out from each other. Since I am not sure exactly which you are interested in, I will tell you about three!

One situation is where a long piece of land sticks out into the ocean or a lake. We call this a peninsula. Florida and Baja California are examples of very large peninsulas, because they are pieces of land that stick out from the continent into the ocean and have water almost all the way around them. But peninsulas can be small too, like a little piece of land sticking out into a lake.


Baja California

Another cool thing, where the entire Earth and its oceans stick out at the sides, is called the “equatorial bulge”. Because Earth is spinning very fast, the part of Earth near the Equator is pushed out from the center of the Earth from the force of its turning. It’s the same force you feel when you are in a car and it turns very fast, pushing you to the side of your seat or when you are on a merry-go- round and you feel like you are going to fly off. The bulge is very small. At the Equator, Earth sticks out only 20 km (12 miles) more than at the north and south poles. Earth is 13 000 km across (8000 miles), so the difference is so small you can’t see it unless you measure it very carefully.

Earth sticks out about 12 miles around the Equator. This sounds like a lot, but Earth is 8000 miles across, so you can only tell by measuring very closely. This is called the Equatorial Bulge.

Another cool thing where the oceans stick out just a little bit from the rest of Earth are the “tidal bulges” : The force of gravity is always pulling between the Moon and Earth. The Moon’s gravity is even pulling on us, but we don’t notice it, because Earth’s gravity is so much stronger (gravity is stronger when things are big and close; Earth is 100 times more massive than the Moon and we are much closer to the center of Earth than the Moon, so the Earth’s gravity on us is a lot stronger). But the strength of the Moon’s gravity is enough to pull the ocean just a little bit toward the moon. This causes the ocean to bulge out about 1-10 feet toward the Moon. As the Moon moves around Earth, the bulge of water moves with it and causes the tides to rise and fall around Earth. This is why we call this bulge of water the “tidal bulge”.

Below is a drawing to help explain the tidal bulges. The size of the bulges in the drawings is exaggerated to help you see them. The actual size of the tidal bulges is typically a few feet, like you see at the beaches in California.

Tidal Bulges

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