Gee, I go on vacation for a week and a half and I miss a lively debate on
one of my fics. :)
Anyway, the 'millions' of times stronger than Hiroshima was suggested by a
couple prereaders and I think it's a good general number for Angela to use.
Remember that in addition to the destruction of Florida, some of that energy
was channeled back to the monoilith and used to blast the Moon, causing some
more sizable craters.
So although millions of times stronger might have caused more damage to
Florida and the surrounding area (all theoretical here, of course), some of
the energy released was sent skyward and didn't remain at the blast site.
The destruction of Florida was mostly a side affect of the Buyierfei needing
the energy to open the portal fully and send energy to the relays on the
moon.
Of course, the people in Florida at the time probably wouldn't call
Florida's destruction a side effect. :)
Check out my AMD info page for before and after pics of Florida to further
illustrate the destruction caused.
http://www.animeprime.com/ff/md/amdindex.html