Can the world end due to reversing poles?

Answer

In the course of geological history, the poles have often ‘reversed’, and the Earth and the biosphere are still there, and have not been significantly affected. ‘Perish’ in the broad sense is therefore unlikely.

We now know that the Earth’s magnetic field protects us against the energetic radiation emitted by the Sun, sometimes in strong pulses. How bad the effect of that radiation is also depends on us. In the 19th century there was a great solar outburst, more than ten times worse than anything we’ve seen since, but it hardly affected our existence. Today it would be a bit different, because the planes, satellites, power grids,…, that we have built in the meantime, are subject to such disturbances. But destroying what we have found for our own comfort need not be equated with ‘perishing’.

The polarity reversal itself is not so bad, what is north and south does not depend on it. There is, however, a phase during the process of the polarity reversal in which the Earth’s magnetic shield protects us less. As said, this is not really life-threatening, but we have to take it into account in our technological applications. And it’s not terribly difficult.