Alex WellersteinVerified account

By "determine" I mean, "national leadership informed and understands", not just, "this one sensor somewhere got the data" 2/

I'm reminded of Clancy's "Sum of All Fears", where snow-covered ground causes US to over-estimate yield of a detonation. Whether that specific issue exists, no one has a lot of practice with wartime nuclear BDA 3/3

I was wondering about this recently. I actually have no idea, especially for detonations in forward positions. Luke? @wellerstein?

I have seen a suggestion (somewhere) that flash time can be used to estimate order of magnitude of burst as well.

(It should be noted that while nuclear wonks are very picky about specific kilotonnage — was Little Boy 13, 15, or 18 kt? — because damage spreads as a cubic root, rough estimates are fine for damage assessment, fallout, etc.)

Luke and Alex, what are the odds that US servicemen, unprompted or prompted, could distinguish between a .5, 5, and 50 kt surface blast? Atmospheric blast?

The real unknown here is the serviceman question. I'd like to think that if you looked at detonations side by side, you can tell, even without a scale reference, that .5 kt is pretty small for a nuke.