We empirically demonstrate that acceptance thresholds for a dendrochronological cross-match of at least t=6 for oak and at least t=7 for pine are required when constructing independent tree-ring master chronologies. These thresholds are far above the "thresholds for significant matches" of t=3.5 or t=4 adopted forty years ago, which are still regarded appropriate for the dating of archaeological samples. We also validate the supra-long Scots pine chronologies from northern Scandinavia using these tightened criteria and our crossdating software CDendro.
The Finnish and Swedish pine chronologies were built by two concurrent teams of scientists working with wood from different places and with different methods. Both teams arrived at the same conclusion regarding the overall dendro signal for the past 7500 years. Our reassessment confirms this conclusion, and demonstrates that both teams worked on a firm level of confidence when accepting dendrochronological matches. This validation is vital for the credibility of our hypothesis about general errors in the European oak masters, errors which were probably caused by using pre-dating with other methods in cases when sufficient dendrochronological confidence levels could not be reached.
Read more here.
Cosmic abrupt radionuclide enrichment events provide a new exciting possibility for the exact dating and synchronization of organic samples or annually resolved sequences of organic samples using 14C measurement. Ice cores can be synchronized to the same events using 10Be measurement instead. The two globally assured events in 775 and 994 have already proved the worth of this concept.
We propose that a third event has been spotted between -2467 and -2465 in bristlecone pine, perhaps together with another event ten years later between -2457 and -2455. By detecting that double-event in wood from the Belfast Long chronology it would be possible to once and for all time determine a definitive date for this European key oak chronology. We also propose that Belfast Long has to be dated eight years earlier than conventionally assumed. This small offset would have far-reaching consequences for the internal linkage of the entire Belfast chronology, and moderate consequences for the radiocarbon calibration curve.
Read more here.
The Eastern Alpine Conifer Chronology is clearly synchronized with the European oak chronologies over the recent 2500 years, thus confirming the long established dendrochronological bridge over the "Roman gap" which we dispute. We claim that the European timber complex archaeologically anchored in Roman time is conventionally dated too old by 218 years. But as the raw measurement data of the Alpine chronology is unpublished and unavailable we can not check whether our hypothesis is wrong, or the chronology is in error. However, some "outliers" in data derived from the chronology seem to tilt the scales in our favor.
Read more here.
Having postulated that the Christian era was inflated with 232 years already when it was invented at the transition from Late Antiquity to Early Medieval time, we were now looking for possible "twin events" with 232 years interval. These are major incisive events which were dated or reported multiple times in different historical contexts so that it seems that they happened twice.
In our new research paper, we discuss the onset of the first plague pandemic and the destruction of the ancient city of Petra in Jordan. Both events are related to the development of Christianity within the Roman empire, which becomes a much more dynamic process with our hypothesis of a drastically reduced Late Antiquity, distinguished as a period of clustered natural catastrophes.
Read more here.
Published or otherwise available European oak tree-ring chronologies archaeologically anchored in Roman time are all separated from early medieval chronologies by a severe timber depletion in late antiquity. Our recent dendrochronological study shows that this gap probably is unnecessarily wide because the Roman dendro complex as a whole appears dated too old by 218 years.
The subject of our astronomical study was to investigate if there is additional scientific support for such a mistake which would mean a large calendar error in the Christian era. Our results indicate that the Christian era was inflated with 232 years already when it was invented. This was done by back-dating West-Roman and related history by means of astronomical retrocalculation after the western part of the Roman empire had declined.
A remarkable result of our astronomical study is that the postulated astronomical/historical error (232 years) appears to be offset by 14 years from the dendrochronological error (218 years). This means that, if we are right, then all current dendrochronological dates within the Roman time complex are given 14 years too young. According to our interpretation, the 14 years offset was caused by an improper synchronization of the Roman dendro complex towards Roman history done more than 30 years ago.
Read all about it in our new research paper.
Several Greek and Roman writers recorded a lunar eclipse that occured before the battle between Alexander the Great's army and Persian forces at Gaugamela near Arbela (todays Erbil in northern Iraq). The date of the battle is given by Arrian as during the month Pyanopsion when Aristophanes was archon at Athens. This means early in the autumn (October) -330 or -329 in our calendar.
There was a large lunar eclipse on -330 September 20, but also a second one on -98 October 6. Both eclipses would date the battle to October as Arrian says, and both were visible in northern Iraq, but at different hours of the night. A strange coincidence is the fact that the two solutions for Pliny's quadruple (see separate report) and the two candidates for the Arbela eclipse are offset by exactly the same number of days: 232 (Julian) years + 16 days = 84754 days.
Moreover, it seems that a Babylonian clay tablet mentioning the battle at Gaugamela has been preserved by a rare coincidence. This tablet contains sufficient astronomical information to date the described battle to -330 October 1 as conventionally assumed.
Even though there are two solutions with 232 years offset for both Pliny's quadruple and the lunar eclipse before the battle at Gaugamela, the Babylonian clay tablet tilts the scales in favour of the conventional solution. However, if our dendrochronological results are correct, something must be wrong with the astronomical records in some way. Ultimately we have to decide which dating method we trust most, and why. Follow our argumentation here.
Starting with the later Han period (25 to 220), there are references to a large civilisation far to the west from China in the Chinese historical records. This civilisation is called Da Qin and has been identified as being either Rome, the Roman Empire or the Roman eastern provinces.
The annalist makes quite fantastic statements about this civilisation, e.g. "their kings are not permanent", and the name of the king of Da Qin in the year 166 was "Andun".
Now, guess what happens if Roman time is offset (i.e. conventionally dated too old) by 232 years. Do the fantastic statements make any sense? Read more about it here.
The Minoan eruption of the Thera (Santorini) volcano provides an archaeological key marker for the Bronze Age chronology of the Eastern Mediterranean civilizations. The exact date for this large eruption is still unknown. Based on published tree ring and ice core chronologies, we investigate the candidates for major volcano eruptions in the middle of the second millennium BC.
Ice core analysis provides indication for the volcanic nature of prominent events which resulted in climatic downturns and which are therefore visible in the tree ring chronologies. Our conclusion is that there are only two candidates for a "supervolcano" eruption in the time range -1675 to -1450. Only one of them has so far been scientifically considered as a candidate for the Thera eruption. However, recent investigations seem to indicate it to be less likely that this candidate is Thera. But there is one unexplored candidate left!
The evaluation of which of the two eruption candidates is the most probable, is backed up by a re-investigation of the so called "Ugarit Eclipse". We also suggest a new synchronization of tree ring and ice core time lines for the time range mentioned.
Read more here.
For quite some time we have been arguing that wood archaeologically anchored in West-Roman time has never been properly crossdated with dendrochronology towards wood of later times. The absence of proper crossdating is apparent as it was necessary to "calibrate" the Roman dendro complex with wood from the Roman camp at Oberaden. (The time that this camp was used can be constrained to a limited range historically.) We argue that the conventional date of the Roman dendro complex is too old by more than 200 years.
Nevertheless modern natural scientists have not always refrained from connecting e.g. their ice core data to historical events of the Roman period, a practice which possibly has led to incorrect results.
But there is hope. Now a group of scientists report on ice core chronologies which do not rely on calibration with historical events like the Vesuvius eruption of RomAD 79 (which occurred in 311 if we are right).
Read more as an update to "Dendro audit".