And any serious answer should say that there is no definite answer to your question, only hints of probable explanations.
True, we haven't perfect knowledge of what factors are necessary to cause an ice-age. However, "hints of probable explanations" is doing quite a disservice to the work put in by people studying this phenomenon. There are differing theories and hypotheses, some with more evidence than others. This does not mean they are simply hints. This may be quibbling over semantics, but the models put forth by climatologists are much more than hints, they are viable theories, which, as has been covered in various threads, means there's more than just one or two pieces of evidence to back them up.
A biblical flood, however, would most probably cause an ice age as you mentioned.
Um. Elaborate, please. How you come by "most probably"? Evidence? Is there a decent climate model for this even? How can you make such a bare assertion on this forum without evidence? You know it's going to get torn apart.
We have many intuitions in our life and the point is that many of these intuitions are wrong. The question is, are we going to test those intuitions?
-Dan Ariely
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