No, Noah's flood makes perfect sense. There is enough ice locked up in the polar regions to cover the earth. The planet is around 70% water right now. And they think that the ice sheets are several miles deep.
The date of Noah's flood was about 2000 BC. That is a rough date. We believe that the earth was created 6000 years ago (around 4000BC) and that the flood occured 2000 years later. A link to your questions about the number of animals are here
Caring for the Animals on the Ark
| Answers in Genesis
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