Oops: New study finds radiocarbon dating can be wildly inaccurate

Posted: September 9, 2015 by tallbloke in data

14cH/T to ‘Scottish Sceptic’ for this story from SCMP.com

Radiocarbon dating, which is used to calculate the age of certain organic materials, has been found to be unreliable, and sometimes wildly so – a discovery that could upset previous studies on climate change, scientists from China and Germany said in a new paper.

Their recent analysis of sediment from the largest freshwater lake in northeast China showed that its carbon clock stopped ticking as early as 30,000 years ago, or nearly half as long as was hitherto thought.

As scientists who study earth’s (relatively) modern history rely on this measurement tool to place their findings in the correct time period, the discovery that it is unreliable could put some in a quandary.

For instance, remnants of organic matter formerly held up as solid evidence of the most recent, large-scale global warming event some 40,000 years ago may actually date back far earlier to a previous ice age.

“The radiocarbon dating technique may significantly underestimate the age of sediment for samples older than 30,000 years,” said the authors of the report from the Chinese Academy of Sciences and Germany’s Leibniz Institute for Applied Geophysics.

“Thus it is necessary to pay [special] attention when using such old carbon data for palaeoclimatic or archaeological interpretations,” they added.

Their work was detailed in a paper in the latest issue of the journal Earth and Planetary Science Letters.

Full story

  1. Which in turns suggests that cosmic ray levels – the primary producer of C14 may have varied significantly.

  2. E.M.Smith says:

    Looks to me like the article is just about lake sediments, not all carbonifrrous objects.

    Since lake sediment can include things like methane eating microbes, coal dust from erosion, etc. I take the article to mean that uncharacterized old dust is hard to date accurately… you need carbon sourced from an air breather… or air breathing plants and their eaters…

  3. EMS you may be right but also there are many AGW believers in German Institutions at the present time who seem not to understand or wish to understand fundamentals of science (particularly where engineering such as electronics, optics, magnetic fields and even reaction kinetics are involved). The question is has the supposed discovery any merit?

  4. E.M.Smith says:

    I think it has merit, but in a more limited scope of sediments, not the all carbon implied by the headlines.

  5. ren says:

    Earth’s magnetosphere cooperates with the magnetic field of the solar wind.

  6. Wayne Job says:

    Recently watched a doco, archaeologists finding stuff that was very old, the part where they said carbon dating is only reliable up to 5 thousand years rings a bell. They then talked about some new method that was based on a different radio activity.

  7. oldmanK says:

    The carbon that is being used as a proxy to date something else may come from a very different chronological era. Could be from k-years from before or after. Establishing contemporaneity is essential.

  8. dscott says:

    You mean a recent study once again … confirms that radio carbon dating is inaccurate without context. This inaccuracy has been known about for a long time which is why oxygen isotopes and potassium argon measurements must be also taken to … calibrate/tune any C14 dating. Tuning and calibration is the scientific establishment’s jargon to claim the imprimatur of science, an appeal to authority as a reference for “rigorous methods” to mislead the public about the so called educated guess on dating.

    Take living material like grass that has grown next to a heavily traveled road and you will end up with grass that sprouted in the spring as having lived thousands of years ago. That is just one type of inaccuracy from environmental causes, i.e. burning a carbon fuel in the presence of plant matter. Now imagine trying to carbon date material that grew/lived during the Deccan Traps era of volcanism! Any period of significant volcanic activity is going to skew C14 readings and that’s on top of the Cosmic Ray effect modulated by the solar wind and solar cycle. All 3 of these significantly skew attempts to date material using C14.

    C14 dating by itself is a useless method and quite frankly other methods are more accurate, why even bother introducing a source of known error? Just because you may like tea doesn’t mean you are wedded to reading tea leaves because they are available from a sense of tradition. It’s an emotional attachment that has worn thin.

  9. dscott says: September 10, 2015 at 3:44 pm

    “You mean a recent study once again … confirms”

    Who is you dscott? Some alumni from UWI? Have you any point whatsoever?

  10. oldbrew says:

    Tim Cullen has run a number of blog posts related to radiocarbon dating problems e.g. in relation to dendrochronology and C14.


    Try this one for example: ‘Carbon 14 – Libby’s Ring’

    Tim Cullen comments: ‘Sadly, this hybrid, high jacked and half-baked Settled Science has now degenerated into a recursive [incestuous] feedback loop where dendrochronology calibrates Radiocarbon Dating which, in its turn, is used to calibrate dendrochronology.’