One of the most attacked and doubted accounts of the Bible is the worldwide flood in Genesis 6-9. The bottom line is either you believe the Bible is the word of God or you don't. If you deny the Bible, no evidence will convince you because you will use your human reasoning to reject it anyway. However, there is plenty of evidence for the sincere - not to prove the Bible but to confirm it. There are several fronts which are used to assault the validity of the Bible in this area. A main one is the animals on the ark. How did Noah get all the animals on the ark? How did they all fit? How did Noah take care of them? How did they redistribute after the flood? The Bible says that God brought the animals to the ark. This is not impossible for God. He is the Creator and Lord of all. Also, animals show an ability to sense danger and know to flee - even when men do not. The tsunami that struck nations around the Indian Ocean on Dec. 26, 2004 killed 230,000 people. Yet very few animal died because they sensed the danger coming and fled to higher ground. Animals can sense an earthquake coming as well and find safety. There were 2 of each of some kinds of animals and 7 of others. It is estimated that based on one definition of what a kind is there had to be about 16,000 individual animals on the ark, the average size of which is about the same as a sheep. Even animals that would grow to be much bigger could have been represented by young, smaller specimens. This would make them easier to care for, and they would live longer after the flood to reproduce more. The ark was 300 cubits by 50 cubits by 30 cubits. It is generally accepted that a cubit is about 18 inches. That would make the ark 450 feet long. There was enough space inside to fit over 500 boxcars, or 136,560 sheep. There would be over 50% of the space left for storage and other things. There are many feasibility studies displayed at the life size ark at the Ark Encounter in Williamstown, Kentucky as well as in writing at answersingenesis.org which show how Noah could have cared for the animals. One theory on how the animals were distributed after the flood is that they traveled on mats of debris that would have been floating on the water. Some atheistic evolutionists even teach a mat theory.
Another avenue of attack on the flood is the idea of uniformitarianism which is essential to the theory of evolution. This is the idea that way things are today is the way they have always been for millions and billions of years. Evolutionists say this makes a worldwide catastrophic event like a flood impossible. Yet these same people propose many worldwide catastrophes to explain the disappearance of the dinosaurs. They can have any theory as along as it does not support the Bible, and some of them even openly admit this. When confronted with evidence of flooding all over the world, they counter that there were many local floods, but not a worldwide one. Some people who say they believe the Bible even say this. There are numerous problems with this idea. One is the evidence does not support this. Another is if the flood Noah survived was local, how did the highest mountains in the world get covered? There are fish fossils on Mt. Everest. If the flood was local, why didn't Noah just move? Why was an ark necessary? If the flood was local, God lied when He promised He would never do that again. It is interesting that the apostle Peter wrote about the flood and deniers of the account saying that all things continue as they were since the beginning (2Pet 3:4).
So what else does the fossil record show that confirms the Bible? There is what the scientists call the Cambrian explosion. This is the sudden appearance of complex life forms all at once, which defies the theory of evolution. Another is the fact that there are fossils at all. Fossils are not created over millions of years. They can only form when a creature is killed and buried quickly by sediment caused by a large column of water. Hmmm. Since there are fossils all over the world, that sounds like there may have been a worldwide flood. Also, the fossil record shows no transitions from one kind to another. The very layers of deposits are named after the distinctions in the fossils. The alleged geological column is a myth created by Charles Lyell. It does not exist in the earth. 15-20% of the history of earth is missing, and 1/3 of the alleged column is missing everywhere. There are polystrate fossils. These are fossils that pass through several layers of sediment such as trees. Are we to believe that a tree stood upright for millions of years while sediment was deposited around it? A much better explanation is that the tree was buried by sediment quickly during the flood. There are folded layers which could only have been deposited quickly by water while the sediment was soft. There is a uniform lack of evidence of any erosion between layers, showing they were all layed down at once. There are horse hoofprints 100 million years before horses, and wasp and bee fossils in the Arizona petrified forest 100 million years before wasps and bees. There are out of order fossils. There is evidence of man in sediment that is allegedly millions of years old. Then there is Mt. St. Helens which reproduced some things the flood did and showed how these processes can happen in hours and not millions of years. It formed a 1/40 scale Grand Canyon with sediment layers, as well as peat layers and the start of a petrified forest in Spirit Lake.
There is much that can be said about the scientific validity of the flood account. You can read much more at answersingenesis.org or by visiting the Ark Encounter. However, the most important thing about the flood is not scientific, but spiritual. The real message for us today from the flood is that God will judge sin and save His people. 1Peter 3:20-21 correlates the flood with water baptism and salvation. Matthew 24:37-38 and 2Peter 3 correlate the flood with the second coming of Jesus Christ. God promised He will never again send a worldwide flood. This time He will judge the world by fire. We can either be like those scoffers and be lost, or we can believe and be saved. It is up to us.