Genesis 8:14-16

"And in the second month, on the seven and twentieth day of the month, was the earth dry. And God spake unto Noah, saying, Go forth from the ark, thou and thy wife, and thy sons, and thy sons' wives with thee."

Aalders pointed out that the word "dried," or "dried up," used in Genesis 8:13, "Means "free of water," while the word used here means, "dry and firm."[12] Thus, it would have been a mistake for Noah to have descended from the ark at an earlier date. The simple way of calculating the duration of the Flood is simply to compare this verse with Genesis 7:11. From the year 600 of Noah's life, 2month, 17th day, to year 601,2month, 27th day is exactly one year and ten days. The big problem, of course, is that men do not know whether the "Noahic year was solar or lunar."[13] The usual opinion of scholars is that, "Noah's year consisted of twelve months of thirty days each."[14]