In Europe it’s now possible to recalibrate the Irish Oaks Δ14C chronology for the 1st Millennium using my trusty digitised Japanese Cedar Isotopic Tree Thermometer.
An initial comparison of the Japanese and Irish chronologies doesn’t appear very promising but there are similarities in the curves between [roughly] 1100 and 1250AD.
Working back in time from 1250 AD it’s possible to unscramble the mainstream radiocarbon dating via inflection point analysis [aka wiggle matching].
Adjusting the original dates in the Irish Oaks chronology based upon this inflection point analysis reveals the Irish Oak Δ14C data is amazingly well synchronised with the Japanese Cedar chronology.
However, the inflection point analysis breaks down at 265 AD and this is totally consistent with a Roman Termination Event occurring around 250 AD.
The adjusted Irish Oak data point at 265 AD was originally dated 128 AD i.e. 137 years too old.
This is not an unexpected result because in the United Kingdom even the Composite Oak Chronologies grind to a halt at 400 AD.
In other words:
The historical chain of evidence fails before the Roman Termination Event.
The major differences are the enhanced minimum at 506 AD in the Irish Oaks chronology whilst the Japanese Cedar minimum at 654 AD is only a minor downturn in Ireland.
But both chronologies confirm the 1st Millennium was traumatic.
An understanding of the problems associated with mainstream dendrochronology and radiocarbon dating can be gained by studying the adjustment values applied to the Irish Oaks chronology.
The original Irish Oaks chronology value at 1004 AD was synchronised with the Japanese Cedar chronology [at 930 AD] by subtracting 74 years from the original Irish Oaks chronology date.
The intriguing aspect of the adjustments back to 600 AD is that they repeatedly return to zero.
This is very suggestive of increased incoming cosmic-debris [and/or cosmic-rays] causing an increase in atmospheric 14C which is then slowly precipitated out of the atmosphere.
This natural mechanism for reducing atmospheric 14C has been observed after the implementation of the 1963 treaty banning the testing of nuclear weapons in the Earth’s atmosphere.
However, the most important aspect of this analysis is that it confirms the Earth experienced a C14 Regime Change around 600 AD.
In other words:
Carbon-14 dating before 600 AD produces results that are “too old” and this error increases as the Calibrated Carbon-14 Chronologies move further back into history.
This major problem with the mainstream methodology can be resolved by establishing regional calibration curves based upon the measured Δ14C values.