The Coriolis effect is caused by the rotation of the Earth. As the Earth spins on its axis, different parts of the planet move at different speeds—the equator moves faster than the poles because it has a larger circumference to cover in the same 24-hour period. This difference in rotational speed causes moving objects, such as air masses and ocean currents, to be deflected from a straight path. Specifically, this deflection is to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This apparent deflection occurs because an object moving over the Earth's surface maintains its initial velocity relative to the Earth's rotation, but the surface beneath it moves at a different speed depending on latitude. As a result, the path of the object appears curved rather than straight when viewed from the rotating Earth

. The Coriolis effect is not a physical force but rather an apparent force that arises from observing motion within a rotating reference frame (the Earth). It significantly influences large-scale phenomena such as atmospheric circulation, ocean currents, and the rotation of storms like hurricanes, which spin counterclockwise in the Northern Hemisphere and clockwise in the Southern Hemisphere due to this effect

. In summary, the Coriolis effect is caused by Earth's rotation and the variation in rotational speed at different latitudes, leading to the deflection of moving objects relative to the surface of the Earth.