 The idea for the polar wind originated with the desire to solve the paradox of the terrestrial helium budget.This paradox consists of the fact that helium in the Earth's atmosphere seems to be produced (via radioactive decay of uranium and thorium) faster than it is lost by escaping from the upper atmosphere.The realization that some helium could be ionized, and therefore escape the earth along open magnetic field lines near the magnetic poles (the 'polar wind'), is one possible solution to the paradox.