What is a Whirlpool?

When most of us think of a whirlpool, we imagine a huge spinning body of water into which people and ships can be sucked and pulled down to their death. While whirlpool are often dangerous, the fact is that there is no suction or downward-draft in them in the open ocean.

Let's see what a whirlpool is. You've probably noticed smaller whirlpool in a brook. They take place where a bank juts out into the current and gives a circular twist to the water.

As the water spins around in the narrow space behind the bank, it tends to pile up on the outside of the circle and to hollow out into a funnel-shaped hole in the center. This is the result of the action of centrifugal force. That is the same force which holds the water in the bottom of a bucket when the bucket is swung around in circles.

What causes the larger whirlpools, those we all know as dangerous to ships and men? When the tide comes sweeping in and it meets the ebb current of the preceding tide head-on, the ocean currents start to move in rotary fashion. This happens quite often in the narrow passages between groups of islands and the shores of the mainland.

When the narrow passage through which the tide flow is very deep, the rotary turning of the water sometimes changes to a
spiraling flow and then a downward-draft to a deep center does take place. But as mentioned before, it doesn't take place in the open ocean. A whirlpool in the open ocean is nothing more than an eddy on a large scale, which simply means a flow of water in rotary fashion.

Whirlpools occur in many parts of the world. The three most famous ones are the Maelstorm, the Charybdis, and the whirlpool downstream from the Niagara Falls. The Maelstorm is located off the Norwegian coast, and the Charybdis lies in the narrow channel between Italy and Sicily.