The Coriolis effect is the curving of winds or currents instead of a straight path. It is caused by the Earths rotation on its axis. Because the Earth rotates, circulating air is deflected toward the right in the Northern Hemisphere and toward the left in the Southern Hemisphere, resulting in curved paths. The Coriolis force applies to movement on rotating objects and is determined by the mass of the object and the objects rate of rotation. Different parts of the Earth move at different speeds, and this difference in speed causes the deflection we observe due to the Coriolis effect. The Coriolis effect affects weather patterns, ocean currents, and even air travel.