C-14 enters the air by the action of cosmic radiation.Cosmic rays enter our Earth's atmosphere from outer space.Some of the scientists who date by C-14 claim these are only small fluctuations and would have no overall effect.But if there can be small fluctuations in the amount of the C-14 produced in the atmosphere day by day, then there could have been greater fluctuations in Earth's history. What might such changes in the atmosphere mean for dating studies?If there are fewer counts per minute, there is not much C-14 in the bone.If all bones have about the same amount of C-14 at the moment of their death, then the scientist can use the C-14 test as something like an hourglass.Let's consider the Flood and use what is called the "canopy theory." There is some evidence for a canopy surrounding the Earth before the Flood.The canopy would probably not stop all the cosmic rays themselves, but a good deal of the scatter radiation would be reduced. Thus, there would be a few neutrons and fewer C-14 atoms formed.
Much of the carbon in the air is C-12, but a small amount of it is C-14.
But the cosmic ray bombardment changes moment by moment, day by day and week by week.