Coriolis effect

In a rotating reference frame, this is the effect that the rotation itself induces on any moving object. It is named in honor of the French engineer and mathematician Gaspard-Gustave de Coriolis (1792-1843), who was the first to describe it mathematically, in a paper published in 1835. On Earth, the Coriolis effect tends to deflect the path of objects moving across its surface, as well as that of geophysical fluids themselves, both water and air. That deflection is to the right in the northern hemisphere and to the left in the south. Any volume of air moving in the atmosphere is subject to this effect, which produces on it a fictitious or apparent force, which adds to the forces acting on the air, such as that due to the horizontal pressure gradient, friction, or centrifugal force, which only comes into play when the paths are circular.