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View Full Version : Comet and the Ice Age



Heike
2003-May-25, 07:02 PM
Somebody seriously told me yesterday that:

The last Ice Age was caused by the impact of a comet.

The onset of the Ice Age was rapid--it took only a week.

This Ice Age killed off all the Neaderthals in the same week.

I am still trying to decide whether to laugh or cry. I need some hard scientific evidence to debunk these first two statements. The person who told me this is highly intelligent and extremely stubborn, so I need something pretty convincing. :roll:

dgruss23
2003-May-25, 07:41 PM
Somebody seriously told me yesterday that:

The last Ice Age was caused by the impact of a comet.

The onset of the Ice Age was rapid--it took only a week.

This Ice Age killed off all the Neaderthals in the same week.

I am still trying to decide whether to laugh or cry. I need some hard scientific evidence to debunk these first two statements. The person who told me this is highly intelligent and extremely stubborn, so I need something pretty convincing. :roll:

One of the current theories for the ice ages is the Milankovich cycles in the Earth's orbit. However another interesting possibility is solar variations (http://www.geotimes.org/june02/WebExtra0621.html).

Regardless of what the cause of the ice ages is, the ice sheets themselves were in some places several km thick and it is difficult to see by what process such thick layers could have formed within a week. In addition, Ice sheets studied today have seasonal layers in them, so there is no evidence to back up the idea of such rapid growth.

You could build a pretty strong case against your friends view if you googled on the topic. Why exactly does your friend think a comet caused all this?

Colt
2003-May-25, 07:47 PM
*ponders how to answer this*

A giant impact from an asteroid could create an asteroid if the amount of dust and debri that it ejected up into the atmosphere were large enough. In this way the dust floating around in the atmosphere would block out much of the light and the Earth would grow cold, starting another ice age.

I do remember hearing something about this might have happened to the Neandrathals but I don't remember clearly. -Colt

Kaptain K
2003-May-25, 07:59 PM
There is no way an Ice age could start in a week, if by that you mean warm and balmy one week and frozen over the next. There is simply too much thermal inertia.

ocasey3
2003-May-25, 10:16 PM
Neandertals lived at the same time as modern humans so I am not sure how a comet or asteroid could have wiped them all out without seriously affecting the rest of the human population. Neandertals were spreadout over the Old World, not in just one area.