Why do cyclones spiral CC in the Northern hemisphere, but CW in the Southern?

Question

If this is true, then what happens on the equator?

Answer 1

its actually a difference in wind cells.

Answer 2

Consider this illustration.Suppose you are standing over the north pole .Now the earth (which is rotating from west to east) will look as if it is rotating from right hand side to the left hand side(conterclockwise).Now you can go to the south pole and stand over there.Now your position will be reversed.When compared to your position on the north pole,now your head will be down and your legs will be up.In this condition, the earth will look as if it is rotating from left hand side to right hand side(clockwise).

Even though the earth is rotating in the same direction, your changed position over the south poles makes you think it is rotating in the opposite direction.

The effect of the coriolis force is similar.Corriolis force is an apparent force which is produced whenever a body is rotating  about its axis.So, this coriolis force is produced when the earth rotates about its axis.This deflects the winds  in both hemisphere in the same direction ;but it looks as if it is deflecting the winds in opposite dirctions in the different  hemispheres as illustrated by the above example.So ,this coriolis force seems to deflect the winds of a cyclone, counter clockwise in the northern hemisphere and clockwise in the southern hemisphere.

This coriolis force is maximum at the poles and zero at the equator.So,winds over the equator will not be affected by this force and will have its own direction depending upon local factors.Usually winds over the equtor will be calm or light variable winds.

Answer 3

Treat the southern hemisphere as a reflection of the northern hemisphere transposed across the equator...  if you flipped the world upside down and looked at the southern hemisphere it would look identical in relation to storm circulation.

Basically, it has to do with the coriolis effect.  The coriolis acts towards the poles... as in it will create a 90 degree tilt to the east in the U.S.  (Winds would naturally blow directly into a low, out of a high).  In the southern hemisphere, the coriolis is acting to push the winds 90 degrees to the west instead.