Exploring abrupt climate change induced by comets and asteroids during human history

A General Chronological History of the Air, Weather, Seasons, Meteors & Comets: In Sundry Places and Different Times: More Particularly for the Space of 250 Years: Together with Some of Their Most Remarkable Effects on Animal (Especially Human) Bodies

14 Responses

  1. Thomas Short is a great resource, and one I often consult, but is not without issues. Historians tend to dismiss him because Short was a woeful historian and took liberties with citations, sometimes even getting the source wrong. In other instances he has some of the dates and events incorrect compared to the original source documents. He sometimes takes liberties with the interpretation of the event, and sometimes even repeats the same event in different years (though this is likely because he is using two different sources which gives two different years – see below)

    An example that comes to mind is the record of a comet in AD 1005 “A terrible comet in the south, vibrating here and there was seen”.

    When you look at contemporary sources you find that this is not a record of a comet in the south in Ad 1005, but rather the record of a supernova in 1006. This supernova appeared close to the horizon for Most northern hemisphere observers, and so would have been subjected to distortion due to the atmosphere. Indeed, short is probably relying upon the account from the Abbey of St Gall in Switzerland which is the most northerly record of the event

    ““AD 1006. A new star of unusual size appeared; it was glittering in aspect and dazzling the eyes, causing alarm. In a wonderful manner it was sometimes contracted, sometimes spread out, and moreover sometimes extinguished. Nevertheless, it was seen for three months in the extreme limits of the south, beyond all the constellations which are visible in the sky” (Annales Sangallenses Maiores).”

    Short seems to have taken the contraction and spreading (which is interpreted as the change in the supernovas light curve from a type Ia supernova) as a vibration. Perhaps though it being close to the horizon at the latitude of St Gall meant that it may have been subjected to atmospheric distortion and extinction. Either way, Short doesn’t give the source of his reference, so it is hard to know.

    There was a comet observed in China and in Europe for 11 days in October 1005, but this appeared in Draco and passed into Cassiopeia, which, both being circumpolar constellations would not be considered the south. So Short may have conflated the comet record and supernova records into one.

    Another example of course is the accounts given in 1012 and 1014, which are accounts of the Michlemass sea floods. The 1012 account appears in Lycosthenes who may have been using the same source as Short.

    “Luna cruento aspectu apparuit. et terra prodigiose mota est. Fax ardens instar turris cum magno fragore e ecclo visa est cadere. Mare latius solito evagat um, urbes aliquot cum multa hominum pernicie inundauit. Fames et pestilentia dein sequutae, tan ra; vis hominum intersit ut pene plures vita defuncta fin, quam seruati”

    Short says “The moon appeared bloody, the Earth was strangely shaken, a burning fire like a tower fell from heaven with great noise. An inundation of the sea overwhelmed many towns in England, Germany etc and much people.” Which is pretty much the translation of Lycosthenes.

    Short tells us his source is the Chron. Magd. which may be the Chronicon Merseburgensis. The 1014 account is from the Anglo Saxon Chronicle. The event was likely in AD 1014 as it was also recorded as such by William of Malmesbury in the Chronicle of the Kings of England. It is worth noting that Michaelmas of 1014 fell near to a new moon, and so the floods may have been due to the combination of a North Sea storm surge coinciding with a high spring tide, similar to the events of the North Sea Flood of 1953.

    The Anglo-Saxon chronicle does not mention the blood moon. then again there was no total eclipses of the moon in 1014. There was a total lunar eclipse in February 1012 though, but this was not visible from Europe. However, we must remember that back then, the new year would have started in March. I.e. this eclipse in february 1012 was actually still 1011 in the calendar at the time. There was a total eclipse in January 10 1013 visible from Europe, which would have been recorded as 1012 in the calendar at the time. So Lycosthenese appears to be correct with the eclipse account, but not with the Michaelmas sea-flood.

    And of course it goes without saying that it is very tempting to try to link the events chronicled in each year, i.e. link the burning tower or fall of clouds with the sea flood, but in reality, there may be no temproal link, or cause-and-effect in them. The Chroniclers had a terrible habit of compiling all the events of a year into one small paragraph, and so could make it appear as if everything was linked.

    So, yes Short is fun and interesting and gives some very fascinating accounts of phenomena, but one must approach it with caution and ideally find and check his original sources where ever possible (but even this can be fun).

  2. There is a somewhat related book by Richard Huggett, Catastrophism: Systems of Earth History. This is given a rather prominent place within the “modern evolutionary synthesis” article in Wikipedia: Under the title of Understanding of Earth history the last of six paragraphs refers to his book, & runs as follows:

    “Catastrophism and extinction events. A partial reintegration of catastrophism has occurred,[Huggett 1997] and the importance of mass extinctions in large-scale evolution is now apparent. Extinction events disturb relationships between many forms of life and may remove dominant forms and release a flow of adaptive radiation amongst groups that remain. Causes include meteorite strikes (Cretaceous–Paleogene extinction event; Late Devonian extinction); flood basalt provinces (Deccan Traps at Cretaceous–Paleogene boundary; Siberian Traps at P–Tr); and other less dramatic processes.” (I have edited out the Wiki square brackets with numerical entries. Instead of Huggett’s name, there appears [44], etc.)

    Personally, the Deccan traps should be amended as caused by the Shiva crater impact (K/T or Cretaceous–Paleogene extinction event), but there is a geological “tradition” that the Deccan precedes Shiva. Upon painstaking search of the publication record, I think this may be spurious. The supposed early Deccan basalts perhaps could be mistaken from Cretacious Rajmahal?

  3. Hermann, I think you may have posted on the wrong thread. Perhaps this was meant for the Awkward but Promising thread?

  4. Jonny, thanks! At 81 years, there is some lack of mental alacrity.

    [Sorry for unmotivated line breaks in my next post.]

  5. Jonny,
    with repect to the possible 11th century event, it may have been recorded on the atlantic coast of NA.
    Abbott found evidence in New York, and there is evidence of tsunami/heavy surges in the outer banks of the carolinas.

    “Curiously, around the same time that archaeologists have dated the destruction of the Ocmulgee earth lodge by fire, a cosmic catastrophe seems to have impacted Earth, likely the result of the Taurid meteor shower. According to the Anglo Saxon Chronicle, on September 28, 1014 AD, a tsunami devastated many towns in England.[10] (In our modern Gregorian calendar this date would equate to October 4, 1014 AD.)[11] Researchers in North Carolina have noted that either a major storm surge or tsunami devastated the coastal areas of the state around this time as well.[12] Considering all the evidence for a major Atlantic tsunami at this time it was most likely this tsunami not storm surge that devastated coastal North Carolina.[13]

    Dallas Abbott of the Lamont Doherty Observatory at Columbia University found tsunami deposits from the same time period in New York, the Caribbean and northern South America.[14] She also found sediment deposits from the mid-Atlantic ridge in an inland bog in New York that also dated to the same time period. Her research concluded that the only thing that could have produced all these effects was a meteor impact in the center of the Atlantic Ocean. Abbott noted that all these events corresponded with a large ammonium spike in the Greenland ice core record similar to other such spikes recorded around the time of known meteor impacts.”


    In my reading I have also found references to a depopulation event along the atlantic seaboard, around the same, that has been attributed to disease.

  6. Cevin

    It is important to remind ourselves of the chain of logic that got us to the initial conjecture of an impact in AD 1014.

    Mike Baillie was looking at the chemical record within Greenland Ice cores, specifically at the AD 540 event, in which he noted that in the GRIP ice core that there was an elevated ammonia signal which was dated by that core to be in 539. He then noted that another exceptionally large ammonia signal occurred in that ice core dated to around 1014. Mike noted that in a different ice core, namely the GISP2 ice core, there was a large ammonia signal in the middle of 1908, which he speculated was due to the Tunguska bolide (a reasonable speculation). This was published in 2006 in Mike’s book “New Light on the Black Death” and also touched upon in Mikes chapter 5 in Bobrowsky and Rickman “Comet/Asteroid Impacts and Human Society” (2007), as well as Baillie 2007 “The case for significant numbers of extraterrestrial impacts through the late Holocene” in Journal of Quaternary Science 22, 101-109 (2007).

    The ammonia at 539 fitted well with Mike’s hypothesis of an impact around AD 539/540 to explain the severe environmental event evidenced by poor tree growth in many trees around the world. The reason why an impact was proposed in the first place was because the ice core evidence at that time had no large volcanic signal at AD 540, the closest one being in around 533 in the ice core chronology which was believed to be the volcanic event that caused the AD 536 dust veil and climatic effects (note that Mike accepted that AD 536 was likely volcanic, but for some reason many people thought he was proposing that AD 536 was an impact).

    And so in 2006 the logic chain went thus: Because ammonia is present in AD 1908 in GISP2, around the very time a verified large cosmic impact occurred, then its presence at 539 may indicate a cosmic impact that caused the AD 540 event. Assuming this then to be true, then the ammonia signal in GRIP dated to 1014 may also indicate another impact event.

    However, we now know that the timescale used for the GRIP ice core is incorrect prior to the 12th Century AD. Mike and I showed that the GRIP ice core was too old by around 7 years prior during the first millennium AD (Baillie and McAneney, 2015), which was then confirmed by Sigl et al (2015). Indeed, previously Sigl et al. had constrained the new NEEM ice core to the GICC05 timescale (which is the timescale constructed from DYE3, GRIP and NGRIP ice cores), but later showed using the two cosmic radiation events in AD 774/5 and AD 993/4 that the GICC05 timescal was too old by 7 and 6 years respectively for these dates. What this means is that the ammonia signals at 539 and 1014 in the GRIP core (and which are also replicated in NEEM) are actually around AD 546 and AD 1020 in real time.

    With this ice core re-dating, we no longer have ammonia at the beginning of the AD 540 event (which is ok since the re-dating also provides a large volcanic eruption at this date), nor is the ammonia at 1014. Furthermore, one can look at the ammonia record in the NEEM core for 1908 and find that there is no elevated ammonia around this date. So now we have a case where not only do we no longer have chemical impact marker at 539 or 1014, but there is a question as to whether Tunguska left an ammonia signal at all in ice in 1908, since the signal is not replicated in the NEEM core.

    Let us now look at the dating of the collapse of the Outer banks off the coast of Carolina. In the papers that first reported the collapse, they blame large storms or hurricanes, but catastrophists like ourselves, having a date date of 1014 for a potential impact in his or her head, would think of a cosmogenic tsunami that would link the Outer bank collapse to the 1014 North Sea inundation. When we look at Culvers et al (2011) the radiocarbon dates for one of the collapses are given as AD 784-985 (at 2-sigma). So effectively they are saying that the event (or events) are dated to within 200 years, and furthermore, does not even fall into the AD 1014 window. But even if we extend the dating to 3-sigma hence the event(s) occurring within the period AD 735-1025, so that 1014 (or indeed 1020!) occurs in the dating window, we still have the issue that we are sucking in a single date (1014) into an event that could have occurred at anytime during a 200-300 year temporal window (or smear). This is almost like blaming the Great Fire of London (1666) on the Tunguska bolide (1908) based on radiocarbon dating a piece of charcoal dated between 1635-1925. By associating the Outer banks date with the 1014 sea flood, we would engage in classic suck and smear. Again, this does not preclude the possibility that the outer banks collapse was due to a cosmogenic tsunami, rather it weakens any association of a cosmogenic tsunami in AD 1014.

    Now we come to the evidence of a cosmogenic tsunami as found by Abbott et al. Journal of Siberian Federal University. Engineering & Technologies 5-29 (2010). I do not have the knowledge or experience to discuss the quality of the evidence that led them to conclude that what they see are tsunami deposits, but again there are issues with the dating. We see in Abbot et al., that the dates for the layers with tsunami evidence are AD 939-1076 and AD 849-1001. In both cases we have temporal windows of almost 130-150 years that the layers could have been formed. Abbott et al again use the erroneous 1014 Ammonia date in the GRIP core and the AD 1014 sea flood to conclude that at least one of these tsunami layers was caused by an Atlantic Ocean impact in AD 1014. As we have seen though, the ammonia does not actually occur in AD 1014, but rather AD 1020, and so cannot be associated with the sea flood of AD 1014. By breaking this chain of logic, we thereby weaken the idea that Abbott et al.’s tsunami evidence was caused by an impact in AD 1014. Assigning a single known date to the 130-150 year temporal window is another example of suck in and smear.

    So what it all boils down to is that in all probability, there was no extra-terrestrial event in AD 1014. Furthermore, the dating of the Outer bank collapse and of Dallas et al’s tsunami evidence are too broad to link to each other, and in particular to any one single date without further proof and/or refinement.

  7. Cevin,

    I cannot comment upon the geophysical evidence, since it is not my area of expertise. Whether the evidence is of impact origin or not is for others to determine. As I have outlined above, it is not whether impacts occurred, but rather the issue of chronology, and trying to link different evidences in different chronologies together. As Abbott et al. correctly state in their paper “In the long term, all of the layers must be located and precisely dated within ice core samples.”

    It is all too easy to draw evidences together when you have imprecise and (unknowingly) incorrect dates for events. The Cosmic Joker doesnt help either by having a giggle at our expense by providing precise (but incorrect dates) that match the dates for extreme events and phenomena in historical records.

  8. Johnny,
    I am not an expert in any of this, just a very interested amateur, but that is why I love the Tusk, because we have the opportunity to discuss with people who are experts in their fields, such as yourself.
    I have thoroughly enjoyed and learned a great deal from reading your replies to various comments and threads.
    So, even if we uncouple the English flood and a lack of exotic chemistry in the ice cores, it still seems that there was some sort of extraordinary event around the beginning of the 11th century.
    And as has been previously said in various papers and articles,”It is in need of further study”.

  9. From this life-time amateur and apprentice science student, just to keep Jonny the chronologist expert in his self-aasigned bounds —

    From Jonny’s Oct 1 post above:

    “What this means is that the ammonia signals at 539 and 1014 in the GRIP core (and which are also replicated in NEEM) are actually around AD 546 and AD 1020 in real time.

    With this ice core re-dating, we no longer have ammonia at the beginning of the AD 540 event (which is ok since the re-dating also provides a large volcanic eruption at this date), …”

    The “large volcanic eruption at this date” is not to be attested by the chronologist. In fact it may well be a secondary eruption subsequent to an ET impact in the Sunda Strait at AD 536. There is a clearly visible [Google Earth] remant of an impact crater at the SW end of the strait (note the characteristic central uplift cone; the crater is slightly deformed due to the ongoing subduction of the Indian Ocean plate beneath the island chain). This supports some Javanese historical traditions that should not be dismissed cavalierly, & Chinese records, too, cited by an linguistic expert i.a., etc etc.

    But this is a great site, and we all owe George for the opportunity to blog and to blab . .

  10. Hermann,

    You don’t have to take a my word for it. Look to the ice core workers themselves (Sigl et al 2015 http://pure.qub.ac.uk/portal/files/16135501/258284_3_high_res_merged_1429871467.pdf), who have shown that previous published ice core dates were wrong. Previously they had a northern hemisphere sulphate signal dated to 529, a tropical signal dated to 533, AND the ammonia at 539. This is was in the NEEM core that they published about in 2013 (Sigl et al. 2013 http://nora.nerc.ac.uk/502097/1/jgrd50082.pdf). Note that they dint discuss ammonia, but you can get the data online to see that they had ammonia around 539.

    Now in 2015, completely independently of Mike and I, they were able to use cosmogenic markers in both ice cores and tree rings to show that NEEM was too old by 7 years in the 6th century. Since NEEM conformed to the GICC05 timescale, this meant this timescale was too old by 7 years in the 6th century, hence the GRIP dates for ammonia were also too old.

    The dates of the eruptions are 536 (for the high latitude Northern signal), 540 (for the tropical latitude eruption), and 546 for the Ammonia. There is even a suspicion that %36 may not have been a single eruption, but may be the result of many northern hemisphere eruptions, as there are multiple North American tephras found in the 536 ice core layer. Ilopango may be the culprit for the AD 540 eruption, and it has also been recently suggested that El Chichon may have caused the AD 536 eruption (http://www.bbc.co.uk/news/science-environment-36086096), but I think it more likely that it if it did erupt at around this time, AD 540 fits the bill better. Of course, as seems to be my mantra of late, we would not know for certain unless tephra from either of these eruptions made it to the ice cores. Certainly, the AD 536 is thought to be due to from an Alaskan eruption(s) (Toohey et al., 2016).

    So it is actually the ice core workers who are attesting it, not me.

    But to back this up further, even climate modelling Toohey et al (2016) (https://www.researchgate.net/publication/301312585_Climatic_and_societal_impacts_of_a_volcanic_double_event_at_the_dawn_of_the_Middle_Ages?ev=auth_pub), have modelled the degree of climate forcing from the sulphate concentrations in the ice cores, and found that the temperature reduction from this forcing matches the temperatures reconstructed from trees. That means that there is no requirement for additional cooling from a large impact.

    But Hermann let me remind you of what I communicated previously with you by email earlier this year, and which others reading may find helpful. Much of the following is copy and pasted from a few of my sent emails in reply to Hermann’s communications, but I have tried to make it so it is followable for others, at the time it was a discussion about whether the eruption of Krakatoa caused the AD 356 event.

    How do we know that Krakatoa likely didn’t cause the AD 536 climatic event? We now have extremely accurately dated ice core records from both Hemispheres, which allows us to reconstruct whether large eruptions are Northern, Southern, or equatorial in location. The reasoning is simple, if you have large sulphate in Greenland cores but not in Antarctica cores, then it is likely extra-tropical Northern hemisphere, and vice-versa. If you find a signal in both Greenland and Antarctica at the same date then it is likely a tropical or equatorial eruption (though one cannot rule out a case where two, or more, volcanoes have erupted in the same year in both hemispheres, at least not without more in depth analysis).

    You can look at the Table 1 in Sigl et al 2013 (See link above), in which the authors list all major eruptions observed in Antarctica (WAIS Divide or WDC-core) and Greenland (NEEM S1) ice cores. We can look at Krakatoa’s 1883 eruption and see that it has a bi-hemispheric profile i.e. it deposited sulphate in both hemispheres. Now compare this with Tambora in 1815, and we see again a strong Bi-hemispheric signal, which is why Tambora caused more of a climatic upset than Krakatoa later that century.

    (Note added for clarity for this post. The dates in this Sigl et al. (2013) paper are the incorrect GICC05 dates, but I cite this paper because they list the sulphate concentrations for all detected eruptions in the past 2000 years in Table 1, compared to the use of a figure as in Sigl et al. (2015) which gives the corrected dates).

    Now, let’s look in the 6th century. It is important to note that the dates at this point in the table are wrong, and are around 7 years too old. In actual fact, the WDC dates are probably 8 years too old, whilst NEEM are 7 years too old. So the dates corresponding to AD 536 and 540 are 528 and 531 in WDC and 529 and 532 in NEEM.

    So lets look at AD 536 which is 528 and 529 in the ice cores. We can see that there is a very strong Northern Hemisphere component to sulphate distribution. This suggests that the eruption was perhaps Northern hemisphere. Indeed, before this paper was published, the signal in other Greenland ice cores led many to conclude that the eruption was a northern latitude extra tropical volcano (see Larsen et al. (2008) https://www.researchgate.net/publication/251427226_New_ice_core_evidence_for_a_volcanic_cause_of_the_AD_536_dust_veil for example.)

    Now there is a small southern hemisphere sulphate signal at AD 536, but it is small. It may be that this was a smaller southern hemisphere eruption which occurred in the same year. BUT one can not rule out (from this table alone) that perhaps there was a small equatorial eruption in AD 536, which contributed to the large Northern Hemisphere signal. So if we assume that the southern component is from Krakatoa, then it appears to be a much smaller eruption than that of 1883. However, we cannot rule out that the magnitude of the Northern hemisphere eruption was so large that some sulphate “spilled over” into the southern hemisphere.

    Let us now come to the matter of the Chinese records of an apparent eruption. So we have this statement in the Chinese records

    “In the year 535, two roars of thunder emanating from the southwest were heard as far away as Nan-king. Clouds of yellow dust soon followed that “rained down like snow” for an entire year, by which time it had accumulated to such an extent that the Chinese could “scoop it up by the handfuls.”

    Nan-King (modern Nanjing) is slightly west of Shanghai. It is probably more reasonable to assume that if the yellow dust was volcanic in origin, it would likely originate from one of Chinas active volcanoes, perhaps Tengchong or Nainan Dao volcano field, the later of which is southwest of Nanjing. So the above passage is not definitive proof of a Krakatoa eruption.

    Then we come to the records of the failed Malay trade missions after 536. We know from the excellent documentary work by David Keys that China was suffering from famine and hardship at this time, so why would Malay be any different? The Ad 536 eruption, may have effected the entire northern hemisphere, if not the entire globe. Perhaps there was not trade in the years after AD 536 because they had enough trouble merely surviving the climatic upheaval without worrying about trade with a country that was also struggling to feed its people.

    Then we come to the matter of the Javanese Annals or Book of Kings. Are they recordings of real events, or just made up? One argument for them not being made up is the inclusion of the description of what sounds to be quite a volcanic eruption. But then one could always base a made up story on real events. I am happy to accept that it is a real recording, but when exactly did the real event happen. Now of course the date for the event is meant to have been around AD 416. David Keys is happy to drag this 130 years forward, citing copying errors etc. But this is a crucial point. It was dragged forward to back up the assertion that the 536 climatic event was due to Krakatoa. Since the physical data in ice cores weakens this hypothesis, then could the date of the Book of Kings event be closer to AD 416? In actual fact, if 416 is indeed a copying error, then it could potentially be any date. Lets go back to Sigl et al 2013, and we see that they give an equatorial eruption around 425/426 in NEEM/WDC respectively. This of course would be around AD 432 after correction. Why cant this eruption be the eruption recorded in the Book of Kings? To really hit the point home, if we look at Sigl et al (2013) yet again, we can see another eruption dated to 566/567, which is really AD 574. This too has a strong bi-hemispheric signal, suggesting it is equatorial. If David Keys can move the Book of Kings date forward 130 years, why not move it forward another 40 years? Could AD 574 then be the Javanese chronicler’s event?

    The Smithsonian’s Global Volcanism program lists AD 416 eruption of Krakatoa as a historically recorded eruption, no doubt using the Book of Kings. You will note though that there is no sulphate in Sigl et al’s table that would correspond to this date in either core (remember it would be around 409 on their table). So either Krakatoa didn’t erupt in 416, or if it did it might not have been a large enough eruption to deliver sulphate to the ice caps of either hemisphere. Indeed, the Smithsonian records its VEI as 4, which while large, is not that large and likely only locally devastating, it is not that large in the global scheme of things.

    This is the trouble with invoking copying errors though, they loosen the constraint of variables for dating, and hence it is easy to suck it into any event you like. Now if there was other internal information to the Book of Kings that helped constrain the date, all the better.

    However, let us now consider your proposition that Krakatoa was sparked off by a close impact. Let us assume that your structure is an impact crater, then let me ask you this (which I have asked you before in private but never received an answer).

    If it is an impact crater, how do you know it was formed in AD 536, and not say AD 416? That is, what geophysical evidence do you have that it was formed in AD 536?

    All in all, things are not being dismissed cavalierly, but being dismissed based upon the hard graft of strong hard science. A linguist reading and translating a text is only as good as the text that he is given.

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