The text states: “the people were evil; the flood erased them from the earth”. However the Midrash equates the flood waters with the waters of creation which are pure and holy; is it good news or bad news? Is Torah in heaven or on earth?
In creating the world, G-d moved from nothing to something. In the new world of Noah after the flood, the creation responded by moving from something to nothing.
After the flood G-d tells Noah of His covenant not to destroy the world again and creates the rainbow to serve as the sign. But isn’t the rainbow simply a natural phenomena?