Carbon dating and its effects
However, if carbon emissions could be drastically reduced, the effects could be reduced or even eliminated over time.
One point to keep in mind is that the important thing about this study isn't that carbon emissions are affecting radiocarbon dating, but the scale at which they are doing so according to Graven's modeling.
The result is that as modern organisms ingest this carbon and eventually die, they, too, seem much older than they actually are.
Graven says that the amount of carbon being pumped into the atmosphere is so great that by 2050, a newly made cotton t-shirt will have the same radiocarbon date as a robe worn by William the Conqueror in the 11th century.
As carbon compounds from these fuels are emitted into the atmosphere, they change the naturally fixed ratio of carbon-14 to other isotopes, so the atmosphere appears much older.
In fact, as she points out, artificial carbon's effect has always been well known since the early days of the technique.
It's called the Industrial or Suess effect, named after Hans Suess, who first studied it.
What allows scientists to measure how much carbon-14 was in an organism when it died is the assumption that the isotope is produced at a more or less steady rate that can be calibrated by comparing radiocarbon dates against more reliable tree ring dating.
Since the ratio of carbon-14 to other carbon isotopes is fixed, and no new carbon-14 is absorbed after an organism dies, it's possible to estimate the time since the organism died going back tens or even hundreds of thousands of years by measuring the ratio of carbon-14 against stable carbon isotopes in ancient organic compounds.