Luckily, we can measure these fluctuations in samples that are dated by other methods.
Tree rings can be counted and their radiocarbon content measured.
In addition, samples need to be thoroughly cleaned to remove carbon contamination from glues and soil before dating.
This is particularly important for very old samples.
A huge amount of work is currently underway to extend and improve the calibration curve.Professor Willard Libby produced the first radiocarbon dates in 1949 and was later awarded the Nobel Prize for his efforts.Radiocarbon dating works by comparing the three different isotopes of carbon.The second difficulty arises from the extremely low abundance of C, making it incredibly difficult to measure and extremely sensitive to contamination.In the early years of radiocarbon dating a product’s decay was measured, but this required huge samples (e.g. Many labs now use an Accelerator Mass Spectrometer (AMS), a machine that can detect and measure the presence of different isotopes, to count the individual C atoms in a sample.Moving away from techniques, the most exciting thing about radiocarbon is what it reveals about our past and the world we live in.Radiocarbon dating was the first method that allowed archaeologists to place what they found in chronological order without the need for written records or coins.Rachel Wood does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.Australian National University provides funding as a member of The Conversation AU.The total mass of the isotope is indicated by the numerical superscript.While the lighter isotopes C has decayed that what remains can no longer be measured. In 5,730 years half of the C in the atmosphere, and therefore in plants and animals, has not always been constant.