What is radiocarbon dating of fossils
The lower the amount of radiocarbon, the older the object.
But big changes in the atmosphere can throw off this method, like releasing tons of extra carbon dioxide into the air from burning fossil fuels.
A new shirt made in 2100, if emissions continue unabated, could appear to come from the year 100, alongside something worn by a Roman soldier.
In short, future human emissions may alter one of the most reliable methods for learning about the past.
The burning of fossil fuels is altering the ratio of carbon in the atmosphere, which may cause objects tested in the coming decades to seem hundreds or thousands of years older than they actually are, according a study published in the Proceedings of the National Academy of Sciences.
The periods of history that archaeologists might confuse with the present-day change based on the different scenarios.
By 2100, a dead plant could be almost identical to the Dead Sea scrolls, which are more than 2,000 years old.
These well-known “aging” properties of atmospheric carbon were pinpointed for different emissions scenarios in a paper published in the yesterday.
But the changes from emissions will require some extra adjustment, even in the study’s best-case-scenario emissions projection.
“If emissions are rapidly reduced, then the decrease in the fraction of radiocarbon in the atmosphere will be equivalent to only about a hundred years of radioactive decay,” said Graven.
“There will be some ambiguities about whether it’s 300 years old or relatively recent.