Considering there’s rarely anyone around for me to say anything to, I’d probably let fly a few choice words and then start trying to work out where the next one was going to land and try to be under it.

That’s assuming you mean nuclear mushroom cloud anyway.

Other, sufficiently large ordnance also generates mushroom clouds and we’ve recovered from a handful of those before.

So any research would be trying to find out whether it was nuclear or not.

I’ve seen Threads. And a whole heap of post-apocalypse stories. I do not want to live in those worlds.