Okay, we have a couple of thousand years to go, but what if this crazy human species lets off hundreds of nuclear explosions at the same time. Isn't that likely to trigger a geomagnetic reversal? As it seems, such a reversal will probably be the least of our problems in such a situation, but for the sake of completeness I want to ask this question. Would the "geography" of nuclear explosions be of relevance (all in one place vs. distributed over the planet). I presume no-one can tell, huh?