The Coriolis pseudo force is no force at all.
It is just a manifestation of a non inertial (e.g rotating) frame of reference.

Imagine an immobile disk with an ant crawling from the center to the edge following a radius.
The trajectory you would see is a straight line because an immobile disk is an inertial frame of reference and as there is no force acting on the ant supposing its motion is balanced by friction (so according to Newton F=m.a => m.a = 0 => a=0 and the movement is a line).

Now same ant but you make the disk rotate to clockwise.
Obviously the trajectory you would see is a curved one because the ant is not only moving along a radius but is also carried by the rotating disk clockwise.
If you try to use Newton again, it doesn't work (from your point of view the acceleration a is obviously non zero, yet Newton says it is 0) and it shouldn't because you must not apply Newton to a non inertial frame of reference.
If you insist and want to write Newton all the same, you must add a non physical correcting factor - let's call it Fc.
E.g you would write F+Fc=m.a. F is still zero but because of the non zero Fc, you obtain a non zero a. And you obtain indeed a curved trajectory.
This correcting factor is called the Coriolis "force" but as you see it is no real force at all - it is just a trick that allows to use Newton for a rotating frame of reference. It's just convenient and makes the trajectory calculations easier.

So now as the Earth rotates, every single object moving on its surface will be subject to this Corolis pseudo force.
It is true for oceanic currents, atmospheric circulation, continents and ants.
Now the value of this pseudo force is very small because the Earth rotates slowly and the trajectories we observe are generally small.
In practice it has only an influence on very large movements like atmospheric cells, cyclonic rotations and oceanic currents.
It has no influence at all on slow movements (like continents) and small movements (like Chick rightly said bathtub drains don't rotate differently in N and S hemisphere)