Coriolis force

n.
A pseudo force used mathematically to describe motion, as of aircraft or cloud formations, relative to a noninertial, uniformly rotating frame of reference such as the earth.

[After Gaspard G. de Coriolis (1792-1843), French mathematician.]

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An apparent, rather than real, force which causes the deflection of moving objects, especially of air streams, through the rotation of the earth on its axis. It shows up, for example, in the movement of an air stream, relative to the rotating earth beneath it. It is equal to -2Ω × V, where Ω is the angular velocity of the earth, and V is the (relative) velocity of the air stream. This apparent force has its greatest deflective effect at the poles, and its least at the equator, this deflection reducing efficiency of an atmospheric cell to transport heat polewards.

The Coriolis parameter is equal to the component of the earth's vorticity about the local vertical and, at latitude φ, is 2Ωsin φ. For a horizontally moving air parcel, the magnitude of the horizontal Coriolis force on the parcel is the product of its velocity and the Coriolis parameter.

Rotating Earth causes moving bodies to deflect
Sooner or later, if you read about ocean currents and the weather that causes them, you’ll come across mention of the Coriolis force, which was discovered by G. G. de Coriolis, a nineteenth-century French mathematician.It’s an inertial force caused by the Earth’s rotation, and its practical effect is to deflect a moving body to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. Thus, the trade winds blowing from north to south in the Northern Hemisphere get deflected to the west, and are felt as northeasterlies. Monsieur de Coriolis’s force is felt by ocean currents, too, so that they make a stately circle to the right in the Northern Hemisphere in the absence of more powerful influences.Don’t worry about the Coriolis force affecting the course of your boat; scientists emphasize that it affects only very large bodies of air or water. They maintain that it has no effect on smaller tidal streams or local winds, and it certainly doesn’t affect the way water swirls out of the plughole, no matter what laymen think. I suspect, however, that it explains why people tend to move in a clockwise circle in fog.See also Accidental Circling; Ocean Currents.

Principal ocean currents of the world demonstrate how the Coriolis force deflects them to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.

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The noun has one meaning:

Meaning #1: a force due to the earth's rotation; acts on a body in motion (airplane or projectile) in a rotating reference frame; in a rotating frame of reference Newton's second law of motion can be made to apply if in addition to the real forces acting on a body a Coriolis force and a centrifugal force are introduced

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