This also has to be corrected for. Second, the ratio of C in the atmosphere at that time to be estimated, and so partial calibration of the “clock” is possible.
Accordingly, carbon dating carefully applied to items from historical times can be useful.
C) dating usually want to know about the radiometric dating methods that are claimed to give millions and billions of years—carbon dating can only give thousands of years.
The flood buried a huge amount of carbon, which became coal, oil, etc., lowering the total C ratio in plants/animals/the atmosphere before the flood had to be lower than what it is now.
Familiar to us as the black substance in charred wood, as diamonds, and the graphite in “lead” pencils, carbon comes in several forms, or isotopes.
One rare form has atoms that are 14 times as heavy as hydrogen atoms: carbon-14, or C ratio gets smaller.
The strength of the Earth's magnetic field affects the amount of cosmic rays entering the atmosphere.
A stronger magnetic field deflects more cosmic rays away from the Earth.