Radiocarbon dating the

All living things exchange the gas Carbon 14 (C14) with the atmosphere around them—animals and plants exchange Carbon 14 with the atmosphere, fish and corals exchange carbon with dissolved C14 in the water.

Throughout the life of an animal or plant, the amount of C14 is perfectly balanced with that of its surroundings. The C14 in a dead organism slowly decays at a known rate: its "half life".

Given relatively pristine circumstances, a radiocarbon lab can measure the amount of radiocarbon accurately in a dead organism for as long as 50,000 years ago; after that, there's not enough C14 left to measure. Carbon in the atmosphere fluctuates with the strength of earth's magnetic field and solar activity.

You have to know what the atmospheric carbon level (the radiocarbon 'reservoir') was like at the time of an organism's death, in order to be able to calculate how much time has passed since the organism died.

But new research shows that commonly accepted radiocarbon dating standards can miss the mark -- calling into question historical timelines.

Archaeologist Sturt Manning and colleagues have revealed variations in the radiocarbon cycle at certain periods of time, affecting frequently cited standards used in archaeological and historical research relevant to the southern Levant region, which includes Israel, southern Jordan and Egypt.

It was the first absolute scientific method ever invented: that is to say, the technique was the first to allow a researcher to determine how long ago an organic object died, whether it is in context or not.

Shy of a date stamp on an object, it is still the best and most accurate of dating techniques devised.Since that time, CALIB, now renamed Int Cal, has been refined several times--as of this writing (January 2017), the program is now called Int Cal13.Int Cal combines and reinforces data from tree-rings, ice-cores, tephra, corals, and speleothems to come up with a significantly improved calibration set for c14 dates between 12,000 and 50,000 years ago.If you continue to browse this site, you are agreeing to our use of cookies. You can disable cookies at any time within your browser settings.Radiocarbon dating is a key tool archaeologists use to determine the age of plants and objects made with organic material.These variations, or offsets, of up to 20 years in the calibration of precise radiocarbon dating could be related to climatic conditions.