Due to the rotation of the earth about its axis, different points on its surface have the same

angular velocity but different linear velocities, which is maximum at the equator and decreases at higher latitudes.

The earth rotating from west to east imparts an eastward velocity to the wind mass. The wind mass moving northward from the equator retains its eastward velocity, which is greater than the eastward velocity of the surface at higher latitudes. Hence, relative to the earth’s surface the wind mass shifts to the end.