Originally posted by spaced_monkey:
the nuclear bombs detonated 1 km above the cites did do more area damage but if the Halifax explosion was 1k up it probably would have be horrifying. (keeping in mind there where ships out at see near Halifax that when the shock wave hit thought they where torpedoed.
Nope. It's simple physics. The ship exploded with less that 300 tons of TNT. That's 0.3 kilotons. A tactical nuke (or a neutron bomb) would probably be around 1 kiloton (kt). It is true that there is a scaling effect that generally works out to the destruction of a given bomb being equivalent to the 2/3 power of the yield. Thus, for example, a pattern of 7 one megaton themonukes would do roughly the same damage as 1 twenty megaton thermonuke.

So, if you want to apply scaling, 15 kt relative to the 0.3 kt is about a factor of 13. However, scaling doesn't really capture unique nuclear effects such as the high radiant energy output which causes fire as well as the prompt radiation. So, while scaling works well for blast effects, other purely nuclear effects would enhance the kill factor.

Bottom line, as bad as a ship carrying explosives would be a nuke is much worse.

Note: if you want to contemplate significantly higher energy chemical explosions, consider what might happen if a liquid natural gas ship were to blow up. If one could contrive to initially release the natural gas and then detonate it - like a fuel-air explosion - you might get low kiloton yields. It's been a while since I looked into this - I'll leave it as an exercise for the student.