In my mind I draw analogies between the Earth and the human body, thinking of the world's rivers and oceans as the circulatory system that keeps this earth alive.

Perhaps the whirlpool surrounding the magnetic mountain is like a heart taking blood in and distributing it throughout the body, for it to return eventually and start the process all over again. Rivers flow continuously, and glaciers melting/water run off is not a sufficient explanation as to where all this water is coming from.