So I was watching an ep of “Naked Science” called “Dino Meteor,” somewhat oddly title as it would seem to imply it was about the Chicxulub Impact. But no, it was a about “The Great Dying,” and the hunt for an impact sight that might have been the antipode of the Siberian Traps. Of course, nothing was resolved, and the verdict is still out on that, but it was still an interesting program.
Anyway. . . They showed a hypothetical impact with Ohio as Ground Zero. They mentioned that for hundreds of miles around, the ground would have been incinerated by the firestorem, and that for even longer, the shockwave would have flatted all the buildings in (eh, Los Angeles?). However, they would have been safe from the firestorm because of the curvature of the earth. In the animation of it as seen from space, the firestorm was shown as spreading out in a plane, more or less tangential to Ground Zero, as opposed to following the landscape. That is, in the simulation, the firestorm continued more or less in a plane, although still continuting past the point of touching the ground. I would have thought that she might still be safe as the result of the firestorm running out of steam, so to speak, not because of the curvature.
What am I missing? Don’t firestorms have to obey gravity, too???
The Younger Dryas Event (or Clovis Comet) was a Tunguska like (but bigger) strike from a comet about 13,000 years ago. The comet air burst over North America and pretty much set the whole continent on fire.
I have to go home and see if they are showing this again. If they are, I need to Tivo it.
Here’s an impact effects calculator that you can play with. It says the fireball would be below the horizon for you, so you wouldn’t have to worry about it. Just the earthquake and the air blast (which would be strong enough to shatter windows and cause 59 mph winds at your distance). And then it would get cold, and dark.
IIRC somewhere I read about the Clovis Comet suggested that with fires as massive as those initially started by the impact they cause their own weather, suck in massive amounts of air and whip into a firestorm that sweeps across the continent.
He may not be hit by the initial flash but I am willing to bet the continent would be uninhabitable within a few days.
The direct lateral force of an explosive impact is absorbed by the earth around it leaving the highest pressure wave “firestorm” to spread only where it isn’t absorbed. The initial crater shows where the earth (horizon) absorbed the lower half of the explosion. The upper half has direct force outward from the center of the explosion. The direction of this force is limited to between sideways and up - but down = crater.
Force itself is not going to be affected by gravity in a noticable amount on that scale. The object affected by the force of the explosion will also be subject to gravity, but the trajectory will be an arc, not a straight line and it will not follow the curvature of the earth.
I’d believe that there would be massive fires, and that they might spread over the whole continent within a few days or weeks. Prevailing winds going from west to east in these latitudes would probably help the fires spread that way, too.
Well, start with bad artwork in the animation – I’m no expert on the physics of firestorms, but there’s absolutely nothing about them that would cause them to take a planar layout that ignores the effects of gravity.
Second, the firestorm is the least of your worries, in a dinosaur-killer-size asteroid strike. There are a wide assortment of deleterious effects thought, with a varying degree of confidence, to result or potentially result from such an impact.
Should you worry? Absolutely not. It would be an extremely rare event, and you could do nothing to change its effect on your life. So, relax. It almost certainly won’t happen, and if it does, you’re screwed. Worry would do you no good; don’t waste your time with it.
As I recall, it appears that one reason the North American impact burned so much of the continent is that it struck at a sharp angle, producing much more of a sideways blast. And resulting in extinctions in NE that heavily favored animals that lived in water or underground as survivors compared to elsewhere; the blast passed over them.
Don’t know what this “safe if over the horizon” happy crap is. I’ve watched several science programs about the Alvarez impactor (Chixulub) featuring common phrases like “set the entire atmosphere on fire” and “global firestorms.” It’s believed that fragments re-entered all over the earth; presumably the parabola of a fragmant thrown up and out and re-entering would carry it around the curve of the horizon.
Chixulub threw molten glass (tektites) completely around the earth; they’ve been recovered from the ocean floor on the antipodal point from the crater. To quote Terminator II: “Anybody not wearing sunblock 3000 is going to have a real bad day.”
I’ve seen enough different explanations for exactly how the firestorm happened that I’m convinced they don’t quite have the details worked out on that one yet. However, it is my understanding that there is evidence of fire all over the globe from that event. Not only would the east coast not be safe, going all the way across the pond to Europe wouldn’t even be safe.
Sailboat’s “set the entire atmosphere on fire” and “global firestorms” seem to be accurate descriptions of at least the magnitude of the event.
Where can I get that sunblock 3000 anyway? You know, just in case.
One program I saw (caveat: TV Science!) said that the roughly 75% of life wiped out by the Alvarez event / Chixulub impactor included 100% of (land) animals over 20 pounds. That is, it’s possible that every single medium and large animal on Earth died.
There were two proposed explanations for this finding. First, large animals generally need more food, and would be disproportionately affected by the impact winter.
Second, as a general rule, large animals don’t tend to burrow. (Don’t ask about grizzlies in caves, this is TV Science!) The implication was that perhaps only burrowing animals survived, and everything on the surface of the earth was killed by the impact and its effects.
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