[ Consider taking a landmass equal to two or three feet of ash the size of Texas, and heating it to a thousand degrees and exploding it into the sky in a second using all of the atom bombs produced by all of the countries, ever.
Then you can begin to comprehend what it would be like. They refer to these as extinction level events for a reason. ]
So glad i built that survival shelter in that deep underground salt mine that has a mini-nuclear reactor and a freshwater well in it...
Well then, send me your address. I am coming to live with you.