Quote:
|
Originally Posted by Martian
So What Do We Do?
Unfortunately, there isn't really very much that can be done to prepare for the worst. In a worst case scenario, it's possible that one of these objects could throw enough dust and debris into the air to start another ice age. Plants would be unable to survive, and the whole food chain would collapse on itself. Smaller objects may only cause local extinction events or throw up a thinner dust cloud. To prepare for these eventualities, one could stock up and canned and frozen goods, so as to have food to survive the disaster. Aside from that, all we can really do is try not to think about it.
|
There actually is a fair amount of stuff our civilization can do to survive an asteroid/comet hit. The key, yes, is to stock up on canned, non-perishable foods -- but you want to build everything underground and hunker down for a few years...
What will the impact do? Well, for starters, there's not much anyone can do within a few hundred mile radius of the impact site. You'll either be incinerated in the impact fireball, or be buried in the ejecta. After the impact, the area will be uninhabitable as it'll essentially be a molten pool of lava for a while, so once the impact site is known -- the key is to flee!
So locally the effects will be devastating, but the impact will still have regional and global effects... For a global extinction level event (think K/T), the ejecta that is ballistically launched upwards out of the atmosphere will eventually settle back to the Earth. This means that you have a large amount of dust entering the atmosphere at high speed, and all of the friction created by this generates a lot of heat -- enough to turn the atmosphere into a broiler. This will raise the temperature at the surface high enough to incinerate plant matter and spark a global firestorm just about everywhere. So everything burns. Once that's over with ... the soot clouds and other chemicals (like sulfur dioxide) that were generated in the impact reside in the atmosphere for several years, helping to dim or completely block out the sun and launch the Earth into a global ice age.
But eventually, things turn back to habitable conditions. Surprisingly quickly, say 10ish years. So the key is to stay underground and survive for that multi-year period, and then emerge from the bunkers and rebuild civilization.
I got basically all of this from watching a special on cable, i think it was discovery channel -- "supercomet: after the impact"