The spectacle of the northern lights might appear at different latitudes.And because more radiation would reach Earth’s surface under very low field strengths during a global reversal, it also might affect rates of cancer.The process involved in reversing the poles of a magnet depends upon whether the magnet is an electromagnet or a permanent magnet.
Every so often the flow of liquid iron is disturbed locally and twists part of the field in the opposite direction, weakening it. It seems they are an inevitable consequence of a naturally chaotic system, and geophysicists observe them frequently in computer simulations.
The implementation of many of these brushless designs however has only been made possible by the availability of inexpensive high power switching semiconductors which have enabled radical new solutions to the commutation problem and much simpler mechanical designs.
By using permanent magnets, rotor windings and mechanical commutation can be eliminated simplifying manufacture, reducing costs and improving reliability.
It’s what makes compasses point north, and protects our atmosphere from continual bombardment from space by charged particles such as protons.
Without a magnetic field, our atmosphere would slowly be stripped away by harmful radiation, and life would almost certainly not exist as it does today.