When it comes to taking things in a literal and concrete fashion inregards to the bible, we haev to remember that this was NOT the A Typical way to do it untill not too long ago.
I think that the ancients understood the difference between telling a story to pass on facts and the story as it was told being FACT.
I believe that there was indeed a flood, a very big one, big enough to be recored by the majority of the civlilizations of the area.
It was a massive flood that would have been "global" in many ways:
For those that believed that where they were was the "world".
For those that, to them, all they had was the "world"
For those that passed on history in the typical fashion of their times.