During the lifetime of an organism, the amount of c14 in the tissues remains at an equilibrium since the loss (through radioactive decay) is balanced by the gain (through uptake via photosynthesis or consumption of organically fixed carbon).However, when the organism dies, the amount of c14 declines such that the longer the time since death the lower the levels of c14 in organic tissue.Scientists across countless disciplines rely on it to date objects that are tens of thousands of years old. An analysis by Heather Graven, a climate-physics researcher at Imperial College London, finds that today's rate of fossil-fuel emissions is skewing the ratio of carbon that scientists use to determine an object's age.Combustion of fossil fuels is “diluting the fraction of atmospheric carbon dioxide containing radiocarbon,” Graven told , the large amount of carbon dioxide in the atmosphere will make new organic material appear to be 1,000 years old based on today’s carbon-dating models.The approach was a sensation when it was introduced.The chemist who developed carbon dating, Willard Libby, won the Nobel Prize for his work.Working with several collaboraters, Libby established the natural occurrence of radiocarbon by detecting its radioactivity in methane from the Baltimore sewer.In contrast, methane made from petroleum products had no measurable radioactivity.
Typically (6): The above list is not exhaustive; most organic material is suitable so long as it is of sufficient age and has not mineralised - dinosaur bones are out as they no longer have any carbon left.
It also has some applications in geology; its importance in dating organic materials cannot be underestimated enough.
In 1979, Desmond Clark said of the method “we would still be foundering in a sea of imprecisions sometime bred of inspired guesswork but more often of imaginative speculation” (3).
By the year 2100, the atmosphere will have a radiocarbon age of 2,000 years old. If Graven's calculations are correct, carbon dating as we know it today will no longer be reliable by the year 2030.
Which means scientists won’t be able to use carbon dating to distinguish between new materials and artifacts that are hundreds or thousands of years old.