The Explosion

I remember when I was younger being fascinated by the effects of nuclear weapons, back then America was in the middle of the Cold War, and the threat of a full scale nuclear attack seemed plausible, even inevitable. Information on the subject was readily available, I even remember a dreary comic book that went through all the sordid effects of an attack on a major city. Not to mention the 80's movie "The Day After". I guess I can put that knowledge to work here. I only wish this did not take place in NY, it's kinda depressing. Come on people can't we find something else to blow up? I digress...

The first thing I looked at was the location. The explosion seems to be coming from an area between the Woolworth Building and the Municipal Building. Right between those two buildings is City Hall

If you look on a map you can see that the Woolworth Building is actually south west of the Municipal Building yet with close inspection of the trailer you can see the fireball is behind the Woolworth Building and partially engulfing the Municipal building. In fact there is no easy way to place a large spherical type explosion at City Hall without completely engulfing the Woolworth. It would be possible I suppose that the explosion is elongated stretching diagonally between Church St. & Vesey St. up to Chambers St. & and Center St. however I think that's over analyzing the CG effect. The more likely answer is the CG artist was probably told to create a cool looking explosion in the general area and that the Woolworth should be kept intact.

The explosion initially appears to be of fairly high yield at or below ground level with the initial fireball diameter at about 1500 feet, a little over a quarter mile, which would put it in line with being around 150 kilotons.

Thankfully there seems to be little or no shock-wave or static overpressure which would level buildings up to 2+ miles away, including the location of Rob's party, in most high yield explosions it is the static overpressure that causes the highest casualties. A 150 kiloton detonation would have a shock-front that travels at 500 mph with a force of 20psi or 360 tons. The lack of shock-wave would suggest the explosion does not carry the characteristics of a nuclear or chemical based explosive.

The fireball must be a relatively low temperature since none of buildings seem to be actually ignited by thermal radiation during the initial blast. When Rob and co. reach ground level there is what appears to be thick black smoke near the Woolworth building and no indication of fire or winds that might be fueling a firestorm. Possibly some catalyst was in the air which burned off quickly causing little further fire damage outside the blast radius.

Although it is not shown in the trailer there would likely be an ominous mushroom cloud rising above the buildings. The latest picture from 01/18/08 was/will be taken about 12 to 15 minuets after the explosion. There is thick white dust in the air and coating everything in the shot. It is unknown if this is dust fallout from the initial blast or the effects a later event.

The initial blast has debris streaming up from it's center of which large chunks are projected up and out to a distance of about a mile (The party location). How this is possible is not clear given the low static overpressure, however it could suggest that the initial blast was below ground. A below ground detonation would remove much of the shock-wave before moving above ground. The air and debris near the point of detonation may be super heated causing a fireball like explosion at ground level after coming into contact with some combustible material such as methane. Still the effects of this would probably knock down buildings in the immediate vicinity.

OK enough over-analyzing of this.