O. K. Here you are in space, poised between the Sun and the Earth, looking at the Earth as it turns below you.

Take a minute to watch one day, from noon to noon. Image copyright Global Presence

Now try to imagine a friend who is standing still directly below you at his or her noon. You would be looking down on him or her, looking at the top of his or her head.

Six hours later, the Earth would turn and you would see that friend from the front.

If you could see through the Earth, 12 hours from the start you would see the bottoms of the soles of your friend's shoes. At 18 hours from the start, you would see the friend's back. After 24 hours, you would again see the top of your friend's head.

The same is true for weather. If, for example, there were a Hurricane in the Gulf of Mexico, at its local noon, you would be able to look down into the eye. But six hours later, you would be looking at the side of the hurricane just before it disappeared as the Earth turns. If you were able to see through the Earth, you would start to see the bottom of the Hurricane until, 12 hours after the start, you would be able to look upward through the eye. At 18 hours, the side of the Hurricane would appear to be coming around the edge of the Earth and at 24 hours, you would again be able to see downward through the eye of the Hurricane.

Back in the early 1800s, Professor Coriolis developed fictious force called the Coriolis force to help us explain it.

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