Here's why:

* The Earth's Rotation: The Earth spins on its axis, and this rotation influences the movement of air masses.

* Inertia: Objects in motion tend to stay in motion in a straight line. However, because the Earth is rotating, a straight line path on the Earth's surface appears curved to an observer.

* Direction: The Coriolis effect deflects objects (including winds) to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.

The Coriolis effect is a crucial factor in shaping weather patterns and large-scale atmospheric circulation.