Published today in the journal Antiquity, a new paper by myself and Mike Baillie revises the Greenland ice core chronologies back to around 2000 BC. We show that the massive climate dislocation beginning in 1627 BC, a date that has been associated with the eruption of the Mediterranean volcano of Thera (modern day Santorini), was actually caused by the caldera forming eruption of Aniackchak in Al
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Jonny McAneney
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Ancient History
I am extremely dubious regarding the claim that it has been absolutely dated to the 16th century BC. Two reasons. First reason is that in order to be absolutely dated one must date the wood by cross dating with an extant tree ring chronology. I do not think that such a tree ring chronology exists for olive trees. The second point is that if it was absolutely dated then we should know the date
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Jonny McAneney
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Ancient History
AKA Dendrochronology works on a global scale!
In an unprecedented collaboration of tree ring and radiocarbon researchers around the world have come together to investigate the AD 774 and 993 radiocarbon excess.
In a nutshell they find that tree ring records accurately cross date globally and that the 774 and 993 cosmic events are recorded coherently in each chronology, with the events lik
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Jonny McAneney
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Laboratory
What is interesting about this article is that it was published about a week before the publication of the results that show that there may be an error in the radiocarbon calibration curve in the 16th and 17th centuries BC. So in this respect, at the time "The Atlantic" was writing, the Olive branch was indeed the contentious evidence, but now, with the new proposed radiocarbon calibra
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Jonny McAneney
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Ancient History
For those in America with access to the Smithsonian Channel, the program Sacred Sites is doing an episode on the megalithic temples of Malta on the 3rd September, which appear to have been abandoned in the mid 24th century BC. The program will touch upon the idea that the abandonment may have been due to climatic effects caused by an impact event around 2350 BC (see my our paper here for example
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Jonny McAneney
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Ancient History
Its nice to see the big guys giving quotes on Pearson et al's results, and they do make very important points. This does indeed have to be replicated in an independent lab, since it is always possible that there is some systematic error within the radiocarbon lab of the study. That said, it is noted in the paper that the lab has shown no bias in recent inter-laboratory comparisons. This l
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Jonny McAneney
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Ancient History
This is something I have hinted at to people for a while now, but couldnt go into too much detail at the time. So a couple of days ago, a paper publishing data that I had seen presented last year at a radiocarbon workshop was finally published (after a gruelling peer review session).
Free access to the paper in html and pdf here
The synopsis of the paper is this. New single year radioca
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Jonny McAneney
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Ancient History
When I had posted the news hadn't hit the media outlets. Rte has picked it up here
Also here
Jonny
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Jonny McAneney
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Ancient History
This drought is good for archaeology. New structures at Newgrange discovered by enthusiasts with drone photography. Looks like a couple of henges
Jonny
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Jonny McAneney
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Ancient History
New research is now attempting to chart the economic history of the Roman empire by examining Lead in ice cores
www.theatlantic.com/science/archive/2018/05/scientists-reclaim-the-long-lost-economic-history-of-rome/560339/
Jonny
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Jonny McAneney
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Ancient History
Later this year the Smithsonian Channel will be airing an episode of their documentary series "Sacred Sites" which discusses the abandonment of Malta around 2350 BC, and features Caroline Malone and fellow researchers discussing the topic.
It should also feature a small segment with me, talking about tree ring evidence and a possible cause of the climate change event around 2350 BC (
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Jonny McAneney
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Ancient History
Gah, I thought that link would have worked. Not to worry, as you say it can be seen in the youtube video at that time mark.
Numbers on graphs are always preferable. I can understand it not being included in this case as the important information for identification is the horizontal axis (the wave number of the Raman shift), not the vertical axis which only gives intensity of the signal.
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Jonny McAneney
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Ancient History
David gives a good lecture here where he discusses how he acquired some of his collection of the glass, and the chemical analyses of the glass and the materials deposited within it.
It is around the 29 minute mark where he presents the chemical analysis of the fragments of "impact diamond" within the glass.
They used a technique called Raman spectroscopy, which measures the rot
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Jonny McAneney
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Ancient History
The 5th March date of the eclipse is given in the proleptic JUlian calendar. In 1223 BC the date in the proleptic Gregorian calendar is 22nd February. The Gregorian calendar is more accurate than the Julian calendar, and keeps the seasons constant with the dates, and so if you want to speak of anniversaries (i.e. a period in which a whole number of tropical years has elapsed), then one must use
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Jonny McAneney
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Ancient History
I have looked at some of the evidence that David Anderson has for an impact in Inner Mongolia, and it can be consistent with an impact source. For example, some of the debris lodged in the Hong Shong glass has been probed with Raman spectroscopy and demonstrates a classic diamond peak. This diamond peak has a large full width at half width which is likely due to strain within the crystal lattic
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Jonny McAneney
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Ancient History
You can view the papers free here . Note this is the same George Howard that runs The Cosmic Tusk blog.
Jonny
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Jonny McAneney
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Laboratory
It is an interesting research piece, if just for its quirkiness. I dont know all the ins and out about it, but I do have a familiarity with it. You will likely have noted the name of one of the authors, who is of course my good lady wife.
I may have a few things twisted here, but if memory serves, this piece grew out of an idea for the Christmas edition of the British Medical Journal (BMJ),
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Jonny McAneney
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Laboratory
The previous post provided a link to a paper which discusses how the Smiley Faces exercise can instruct researchers on how to plan and conduct a good clinical trial. The following is a link to the second paper which outlines the results of many Smiley Face exercises.
Inconsistencies in the drawing and interpretation of smiley faces: an observational study
QuoteResults
We collected 723
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Jonny McAneney
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Laboratory
Lol. It was just begging to be done really
Jonny
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Jonny McAneney
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Laboratory
How does one go about designing a good, non-biased clinical trial? Drawing Smiley Faces can help!
Using the Smiley Faces task to teach the fundamentals for good clinical trials
QuoteResearchers planning a clinical trial should have a clear research question that they wish to investigate and which they will seek to answer in their study. The task of defining a research question lays the fo
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Jonny McAneney
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Laboratory
The 27.9 times that of earth figure is correct but the wording used to express it is imprecise . What they are speaking off is the gravitational field strength of the surface which is commonly referred to as the acceleration due to gravity at the surface. The value for this on the surface of the sun is around 274 m/s^2 compared to earth's 9.81 m/s^2. Thus the suns surface gravity is indeed
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Jonny McAneney
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Laboratory
You are correct that volcanoes are constantly erupting around the world, but the vast majority of these "background eruptions" are relatively small. So if you were to measure any apparent correlation between these background eruptions and social unrest in ancient societies then you will not have anything of significant meaning. As you say there is just far too much noise. But the poi
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Jonny McAneney
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Ancient Egypt
I have had a sneak peak at some of the data that Charlotte is collecting and it should it continue in the same trend there will be some interesting papers published in the next couple of years. I know that sounds like a very vague and generic horoscope-esque prognostication, but the presentation of some preliminary results at a radiocarbon meeting last month generated a bit of discussion.
Jon
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Jonny McAneney
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Laboratory
It isnt that fast really. The preprint of the paper, and reporting of the preprint appeared a year and a half ago, so plenty of time for the scientific community to have discussed the paper before it was officially published in a journal.
Jonny
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Jonny McAneney
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Laboratory
In October last year, Mike Baillie and I published an article in the conference proceedings “2200 BC – A climatic breakdown as a cause for the collapse of the Old World?”. The six month embargo on it appearing digitally was lifted today.
The article title is “Why we shouldn’t ignore the mid-24th century BC when discussing the 2200-200 BC climate anomaly.”
The focus on the conference was on
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Jonny McAneney
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Laboratory
It does seem a bit of a stretch to suggest that two eruptions in 536 and 540 (actually three, but I dont think the 547 eruption was that big in my opinion), could cause 125 years of global cooling. Certainly the effects of the 540 eruption are much greater than 536, but yet it has seemingly escaped the historical record, while the 536 effects are well recorded (the 18 month dust veil for example
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Jonny McAneney
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Laboratory
Investigation of European and Central Asian tree ring series has revealed a 125 year period of dramatic cooling in the 6th and 7th centuries AD. This cooling is thought to due to the two large volcanic eruption of AD 536 and AD 540, and sustained by low solar activity combined with ocean and sea ice feedback mechanisms.
The paper is published in Nature Geoscience here . Most may not be able
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Jonny McAneney
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Laboratory
I was never convinced by the Impact origin for the excess radiocarbon.
A paper published in Nature Communications at the end of last month which reports isotopic analysis from ice cores that the origin of the event was most likely the intense solar storms, and not caused by an impact, supernova, or gamma ray burst.
The full paper can be read here
Jonny
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Jonny McAneney
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Laboratory
I am lazy and like to call it the 774 event. It should more accurately be called 774-775 event. more on the timing of the event here <;
Jonny
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Jonny McAneney
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Laboratory
The timing of the 774-775 event has been refined to be March 775 +/- 6 months, by comparing the timing of the 14C excess in new Zealand trees with northern hemisphere trees.
Guttler, D. et al. Rapid increase in cosmogenic 14C in AD 775 measured in New Zealand kauri trees indicates short-lived increase in 14C production spanning both hemispheres. Earth Planet. Sci. Lett. 411, 290–297 (2015).
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Jonny McAneney
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Laboratory