Porter raises the question "have Belfast [meaning dendrochronology at Queen's University, Belfast] and if so, by a large amount or a small amount? Unless the German dendrochronologists (or possibly the Americans) make their data available, there is no way to check. The low Egyptian historical chronology should not be ruled out until dendrochronologists, particularly German dendrochronologists, provide some evidence that their work is correct back to the second millennium BC."

There are many points to this.

1) It is understandable that Dendrochronologists do not want to make their data public outside of their field. Most dendrolabs run as a commercial dating service (not the same type as Match.com, but you never know ). Why would they essentially hand out the information that could prevent them bringing in a revenue to their host institutions?

2) Porter emphasises the work of Cybis Dendrochronology. Cybis believes in a form of phantom time, and that there are over 200 years of additional history added in around teh roman period i.e. Caesar was assassinated in the late 2nd century, not 44 BC. They have argued that the Belfast chronology is wrong, due to the presence of gaps (which have been successfully bridged using neighbouring English Oak from the Roman period). Similar phantom time arguments exist, and have been shown to be chronologically incorrect. See here [www.q-mag.org]

What the above link shows is that the radiocarbon curve is continuous arcoss the Irish oak gap. Furthermore it matches the American curve extremely well. If the bridging across the AD/BC gap was not correct, we would not see this.

3) Porter has emphasised that unless the dendrodata is made public, we will never know if errors exist. But the point is that within the dendrochronology community, they can tell if errors exist. To successfully point out an error in a chronology is like proving a tenet of physics wrong. It is a big thing. The example used in Porters article is that of the German Holstein chronology being shown to be 71 years offset. This was a big deal in dendrochronology, and brings much kudos if you manage to point out another labs error. No one has done so within the professional dendrochronologists regarding Any of the current American, or European chronologies.

But just because all the data from America and Europe has not been made public, does not mean that we cannot check the dating in a broad sense. We can look at data that has been published or made available on teh web (on the NOAA paeleoclimate) Take for example the following key dates. AD 536, 44 BC, 207 BC, 1627 BC. When we look at European chronologies (say the Tornetrask pine) Irish/British Oak, and American bristlecone pine, we see markers for low temperature, poor growth, and frost damage rings, with matching years. For example, we see cooling in 536, 44 BC, 207 BC, and 1627 BC in Swedish pine, We see poor growth in Irish oak in the same dates, and forst rings in 536, 43 BC, 207 BC and 1627 BC. If the Belfast chronology was incorrect, then how does it replicate these other chronologies?

4) Much emphasis is placed upon the belfast chronology and german chronology's inclusion in the radiocarbon calibration curve. This calibration curve can be replicated using solely Bristlecone pine, which has the advantage that since it is such a long lived tree and thus eliminates the need to cross date samples (where alleged errors could arise) to produce a chronology. That is, in theory you could cut down the longest living tree (or take a core sample from it) which is around five thousand years old, and measure the 14C concentration in each ring, and form a basic curve from that. of course, you would need more samples for statistical significance, but the above illustrates the point. The bristlecone pine independently replicates the European chronology both in radiocarbon and dendro-dating.

Jonny

The path to good scholarship is paved with imagined patterns. - David M Raup