Here's a thought. Would it had been a lot simpler for God to tell Noah, gather all the animals at the top of the mountain and your family, I will bring rain for 40 days until it reach about 50 feet from the top. That way all will be safe and you have vegetation plus it not necessary to cover all the mountain top. No need to spend years a building a boat, more time to preach...
Cool! How about this;
God speaking; Good morning Noah, can you do some clean up, I just killed all the evil people last night in their sleep, plus you can kill a cow and enjoy hot-dogs tonight because I didn't kill any of the millions of animals.
(2 Kings 19:35) And it came about on that night that the angel of Jehovah proceeded to go out and strike down a hundred and eighty-five thousand in the camp of the As·syr′i·ans. When people rose up early in the morning, why, there all of them were dead carcasses. . .