Saturday, 7 July 2012

Supervolcanoes & the Dark Ages

Eruption in 535 AD killed a huge percentage of the world’s population

Krakatoa – No plant growth for 2 years

by Michael Relfe (Excerpts)

“In AD 535/536 mankind was hit by one of the greatest natural disasters ever to occur …. It blotted out much of the light and heat of the sun for 18 months and resulted, directly or indirectly in climatic chaos, famine, migration, war and massive political change on virtually every continent”.

This is in the opening page of “Catastrophe” by David Keys, 1999, a book that should have been on the best seller lists but very few people know of. This article is an attempt to summarize that book and discuss some of the implications.

Parts of the U.S. once covered by ash from Yellowstone eruptions of 2 million and 630,000 years ago, compared to 760,000-year-old Long Valley caldera eruptions at Mammoth Lakes, CA, and 1980 eruption of Mount St. Helens, WA. (Adapted from Sarna-Wojcicki, 1991.)

The contemporary Roman historian Procopius described the mystery climatic disaster: “The sun gave forth its light without brightness like the moon during this whole year.”

Sixth century historian and prominent church leader John of Ephesus wrote of 535 AD in his ‘Historiae Ecclesiasicae’ (‘Church Histories’), “There was a sign from the sun, the like of which had never been seen and reported before. The sun became dark and its darkness lasted for 18 months. Each day, it shone for about four hours, and still this light was only a feeble shadow. Everyone declared that the sun would never recover its full light again.”

Another 6th Century writer Zacharias of Mytilene wrote, “The sun began to be darkened by day and the moon by night.”

A Roman official known as John the Lydian reported that “the sun became dim for nearly the whole year.”

In Italy a Senior local civil servant, Cassiodorus Sentaro wrote in 536, “We marvel to see no shadows of ourselves at noon….We have had a spring without mildness and a summer without heat.”

According to Keys, this one global disaster directly or indirectly caused the deaths of a huge percentage of the world’s population. It indirectly affected the politics on every continent and contributed to the fall of the Roman Empire. The 100-year period after it occurred is the heart of history’s so-called Dark Ages.”

In 536 the Japanese Great King Senka wrote, “Yellow gold and ten thousand strings of cash cannot cure hunger. What avails a thousand boxes of pearls to him who is starving of cold?”

* * *

Relfe goes on to give more evidence of a major global disaster in 535 A.D., including the collapse of the great Mexican city of Teotihuacan and the many plagues of the time, including the ‘Great Death.’ He then pinpoints Krakatoa as the culprit, and goes on to reconstruct the Eruption.

“Could such a catastrophe happen again?” asks Relfe.

Yellowstone National Park is the world’s largest dormant volcano, Relfe notes. It covers 1,500 square miles. It will almost certainly one day burst forth upon the world as Krakatoa did. “It appears to erupt roughly once every 600,000 – 700,000 yeas – and the last eruption was exactly 630,000 years ago,” said Keys. “What’s more, the last decade has seen a substantial increase in potential pre-eruption activity”.

Keys wrote in 1999: “Since 1988, upward pressure exerted by the magma reservoir and magma-heated water-vapour has forced hundreds of square miles of land to rise by three feet….

Then Relfe speaks of the currently dormant super-volcano in Long Valley, California, and the one beneath Naples, Italy. The super-volcano in Italy is known to have erupted cataclysmically twice – once 37,000 years ago, and again 12,000 years ago.

(Note: These dates roughly correspond with the Lake Mungo magnetic reversal and the Gothenburg magnetic reversal.)

Relfe also mentions the increasing restlessness of Rabaul in Papua New Guinea, along with five other large potentially active caldera volcanoes in the Alaskan Aleutian Islands and Mexico….”If any one of these volcanoes explode, world climate would be plunged into chaos, precisely as it was in the sixth century”, says Relfe.

When Yellowstone blows, Las Vegas and Phoenix will be covered with a three foot layer of ash,” says Keys.

So long as you don’t live within a very large radius of the volcano itself, you will not be killed immediately. However, a BBC documentary said that one super volcano killed animals by covering them with ash 1,600 km (1,000 miles) away!. So it is clear that if Yellowstone blows a big one, it will wipe out about half of the US.

At one time, Michael had posted this entire article on his website (http://www.relfe.com/). Unfortunately, he has taken it back down. I’m trying to talk him into re-posting it.

In the meantime, here’s more info about the extreme weather events of 535-35:

From Ice Age Now @ http://iceagenow.info/2012/03/krakatoa-%E2%80%93-plant-growth-2-years/

536 AD and all that

— gavin (

) (

)

“during this year a most dread portent took place. For the sun gave forth its light without brightness… and it seemed exceedingly like the sun in eclipse, for the beams it shed were not clear.”

This quote from Procopius of Caesarea is matched by other sources from around the world pointing to something – often described as a ‘dry fog’ – and accompanied by a cold summer, crop failures and a host of other problems. There’s been a TV special, books and much newsprint speculating on its cause – volcanoes, comets and other catastrophes have been suggested. But this week there comes a new paper in GRL (Larsen et al, 2008) which may provide a definitive answer….

It’s long been known that tree-rings (such as the one pictured from Arizona) often show an extremely small growth ring for AD 536 (you can count back from the marked AD 550 ring). In fact, if you look at the mean anomaly in a whole range of tree ring constructions, this event stands out along with 1601 and 1815 (known volcanic events) as being exceptional over the last 2000 years.

last 2000 years.

Average of the high-frequency components of 7 northern European tree ring reconstructions from Larsen et al, 2008. The filtering ensures that uncertainties in long term trends (which are not important in this context) don’t confuse the issue.

These data match the written sources quite well. However, tying it to a cause has always been plagued with problems of chronology. An initial attempt to tie this event to a volcanic pulse in the Dye3 ice core in Greenland foundered when the chronology was revised to put it 20 years earlier. However, there has recently been a concerted effort to place all the Greenland ice cores on a common timescale based on annual layer counts (Vintner et al, 2006). Because all the cores are being counted together, ambiguities in one can be corrected by reference to the others. Once the dates have been better established, the sulphate records (which generally show the impact of volcanic aerosols) can be examined to see if they line up. And low and behold, they do:

The second peak in the picture is dated at 534 AD which is close enough to 536 AD given the one or two year uncertainty in counting. Note that the 534 AD peak is actually smaller than the one a few years earlier. In assessing the importance of an eruption though, it isn’t enough to have just a peak in Greenland. That could simply signify an eruption that was close by. Instead, people look for a matching peak in Antarctica. This signifies that the eruption was likely tropical and the aerosols were carried into both hemispheres by the stratospheric circulation. Here is where previous attempts often faltered.

The dating of ice cores in Antarctica is less exact than in Greenland because the accumulation is slower (it doesn’t snow as much). However, the relatively new Dronning Maud Land (DML) core has comparable resolution to the Greenland ones, and this one does have a clear sulphate peak at about 542 +/- 17 years. That is good enough to be a match to the 536 AD peak in Greenland. The correction you’d need to make to align them exactly would also fix some other apparent offsets for smaller events in the subsequent 100 years.

So it probably was a volcano, somewhere in the tropics, and it was likely the size of Tambora in 1815. There has been some speculation that it was an earlier eruption of Krakatoa (which went off again in 1883), but that is uncertain, as are the numerous consequences such as the fall of the Rome or the rise of Islam which have been attributed to this event. While not exploring that too deeply, this quote from Michael the Syrian indicates dramatically the potential for climate events like this one to really spoil your day:

“The sun was dark and its darkness lasted for eighteen months; each day it shone for about four hours; and still this light was only a feeble shadow … the fruits did not ripen and the wine tasted like sour grapes.”

From Real Climate @ http://www.realclimate.org/index.php/archives/2008/03/536-ad-and-all-that/

https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiJ31ymWXi4A_abeZwa6lchVarCK87gNWRUn6Pjf-D5fTz8xtKDdMRybUNLWg16oMWo1jqDm7x1wlYLuhfY4S7P8k9JhaegXOq_R8juHcvCejWJIwLEE7Yo5RtpCYzoo_LiBl8IRijws6Q/s1600/article-1342820-0C9D461F000005DC-599_634x1182.jpg

Extreme weather events of 535–536

The extreme weather events of 535–536 were the most severe and protracted short-term episodes of cooling in the Northern Hemisphere in the last 2,000 years.^[1] The event is thought to have been caused by an extensive atmospheric dust veil, possibly resulting from a large volcanic eruption in the tropics,^[2] or debris from space impacting the Earth.^[3] Its effects were widespread, causing unseasonal weather, crop failures, and famines worldwide.^[3]

Documentary evidence

The Byzantine historian Procopius recorded of 536, in his report on the wars with the Vandals, "during this year a most dread portent took place. For the sun gave forth its light without brightness...and it seemed exceedingly like the sun in eclipse, for the beams it shed were not clear."^[4][5]

The Gaelic Irish Annals^[6][7][8] record the following:

· "A failure of bread in the year 536 AD"—The Annals of Ulster

· "A failure of bread from the years 536–539 AD"—The Annals of Inisfallen

Further phenomena reported by a number of independent contemporary sources:

· Low temperatures, even snow during the summer (snow reportedly fell in August in China, which postponed the harvest there)^[9]

· Crop failures^[10]

· "A dense, dry fog" in the Middle East, China, and Europe^[9]

· Drought in Peru, which affected the Moche culture^[9][11]

Scientific evidence

http://upload.wikimedia.org/wikipedia/commons/thumb/7/7d/Tree.ring.arp.jpg/250px-Tree.ring.arp.jpg

Tree ring analysis by dendrochronologist Mike Baillie, of the Queen's University of Belfast, shows abnormally little growth in Irish oak in 536 and another sharp drop in 542, after a partial recovery.^[12] Similar patterns are recorded in tree rings from Sweden and Finland, in California's Sierra Nevada and in rings from Chilean Fitzroya trees.^{[citation needed]} Ice cores from Greenland and Antarctica show evidence of substantial sulfate deposits around 533–534 ± 2 years, evidence of an extensive acidic dust veil.^[2]

Possible explanations

It has been conjectured that these changes were due to ashes or dust thrown into the air after the impact of a comet^[13] or meteorite,^[14][15] or after the eruption of a volcano (a phenomenon known as "volcanic winter").^[16] The evidence of sulfate deposits in ice cores strongly supports the volcano hypothesis; the sulfate spike is even more intense than that which accompanied the lesser episode of climatic aberration in 1816, popularly known as the "Year Without a Summer", which has been connected to the explosion of the volcano Mount Tambora in Sumbawa, Indonesia.^[2]

In 1984, R. B. Stothers postulated that this event might have been caused by the volcano Rabaul in what is now Papua New Guinea.^[17]

In 1999, David Keys in his book Catastrophe: A Quest for the Origins of the Modern World (supported by work of the American volcanologist Ken Wohletz), suggested that the Indonesian volcano Krakatoa exploded at the time and caused the changes.^[16] It is suggested that an eruption of Krakatoa attributed to the year 416 by the Javanese Book of Kings actually took place at this time–there is no other evidence of such an eruption in 416.^{[citation needed]}

In 2009, Dallas Abbott of Columbia University's Lamont-Doherty Earth Observatory in New York published evidence from Greenland ice cores that multiple comet impacts caused the haze. The spherules found in the ice may originate from terrestrial debris ejected into the atmosphere by an impact event.^[1][18]

In 2010, Robert Dull, John Southon and colleagues presented evidence suggesting a link between the Tierra Blanca Joven (TBJ) eruption of the Ilopango caldera in central El Salvador and the AD 536 event.^[19] Although earlier published radiocarbon evidence suggested a two-sigma age range of AD 408–536,^[20] which is consistent with the global climate downturn, the connection between AD 536 and Ilopango was not explicitly made until research on Central American Pacific margin marine sediment cores by Steffen Kutterolf and colleagues showed that the phreatoplinian TBJ eruption was much larger than previously thought.^[21] Detailed AMS 14C dating of successive growth increments from a single tree killed by a TBJ pyroclastic flow supports a death age for the tree of AD 535. A conservative bulk tephra volume for the TBJ event of ~84 km3 was calculated, indicating a large VEI 6+ event and a magnitude of 6.9. The results suggest that the Ilopango TBJ eruption size, latitude and age are consistent with the ice core sulphate records of Larsen et al. 2008.

Historic consequences

The 536 event and ensuing famine has been suggested as an explanation for the sacrifice by Scandinavian elites of large amounts of gold at the end of the Migration Period, possibly to appease the angry gods and get the sunlight back.^[22][23]

The decline of Teotihuacán, a huge city in Mesoamerica, is also correlated with the droughts related to the climate changes, with signs of civil unrest and famines.

David Keys' book speculates that the climate changes may have contributed to various developments, such as the emergence of the Plague of Justinian, the decline of the Avars, the migration of Mongolian tribes towards the West, the end of the Persian Empire, the rise of Islam, and the fall of Teotihuacán.^[11] In 2000, a 3BM Television production (for WNET and Channel Four) capitalized upon Keys' book. This documentary, under the name Catastrophe! How the World Changed, was broadcast in the US as part of PBS's Secrets of the Dead series. However, Keys and Wohletz' ideas are not widely accepted at this point.^{[citation needed]} Reviewing Keys' book, the British archaeologist Ken Dark commented that "much of the apparent evidence presented in the book is highly debatable, based on poor sources or simply incorrect" and that "Nonetheless, both the global scope and the emphasis on the 6th century AD as a time of wide-ranging change are commendable, and the book contains some fascinating and obscure information which will be new to many. However, it fails to demonstrate its central thesis and does not offer a convincing explanation for the many changes discussed."^[24]

Notes

1. ^ ^a ^b Abbott, D. H.; Biscaye, P.; Cole-Dai, J.; Breger, D.; Biscaye; Cole-Dai; Breger (12/2008). "Magnetite and Silicate Spherules from the GISP2 Core at the 536 A.D. Horizon". AGU Fall Meeting Abstracts 41: 1454. Bibcode 2008AGUFMPP41B1454A. Abstract #PP41B-1454.

2. ^ ^a ^b ^c Larsen, L. B.; Vinther, B. M.; Briffa, K. R.; Melvin, T. M.; Clausen, H. B.; Jones, P. D.; Siggaard-Andersen, M.-L.; Hammer, C. U. et al. (2008). "New ice core evidence for a volcanic cause of the A.D. 536 dust veil". Geophys. Res. Lett. 35 (4): L04708. Bibcode 2008GeoRL..3504708L. doi:10.1029/2007GL032450. http://www.agu.org/pubs/crossref/2008/2007GL032450.shtml.

3. ^ ^a ^b Than, Ker (3 January 2009). "Slam dunks from space led to hazy shade of winter". New Scientist 201 (2689): 9. Bibcode 2009NewSc.201....9P. doi:10.1016/S0262-4079(09)60069-5.

4. ^ Ochoa, George; Jennifer Hoffman; Tina Tin (2005). Climate: the force that shapes our world and the future of life on earth. Emmaus, PA: Rodale. ISBN 1-59486-288-5., gives this quote as "The Sun gave forth its light without brightness, like the moon during this whole year, and it seemed exceedingly like the Sun in eclipse".

5. ^ Procopius. History of the Wars, Books III and IV: The Vandalic War. Dewing H.B.. ISBN 1434605507. http://www.gutenberg.org/files/16765/16765-h/16765-h.htm.

6. ^ Gaelic Irish Annals translations

7. ^ Documents of Ireland

8. ^ The Annals of the Four Masters

9. ^ ^a ^b ^c Ochoa, George; Jennifer Hoffman; Tina Tin (2005). Climate: the force that shapes our world and the future of life on earth. Emmaus, PA: Rodale. p. 71. ISBN 1-59486-288-5.

10. ^ Rosen, William (2007). Justinian's flea: Plague, Empire and the Birth of Europe. London: Jonathan Cape. ISBN 0-224-07369-9.

11. ^ ^a ^b Keys, David Patrick (2000). Catastrophe: an investigation into the origins of the modern world. New York: Ballantine Pub. ISBN 0-345-40876-4.

12. ^ The Holocene 1994 fig 3 page 215 "Dendrochronology, the AD536 dust-veil event"

13. ^ MacIntyre, Ferren (2002). "Simultaneous Settlement of Indo-Pacific Extrema?". Rapa Nui Journal 16 (2): 96–104.

14. ^ Baillie, M. G. L. (1999). Exodus to Arthur: Catastrophic Encounters with Comets. London: B.T. Batsford. ISBN 0-7134-8352-0.

15. ^ Rigby, Emma; Symonds, Melissa; Ward-Thompson, Derek (February 2004). "A comet impact in AD536?". Astronomy and Geophysics 45 (1): 1.23. Bibcode 2004A&G....45a..23R. doi:10.1046/j.1468-4004.2003.45123.x. http://www.blackwell-synergy.com/doi/pdf/10.1046/j.1468-4004.2003.45123.x.

16. ^ ^a ^b Wohletz, Ken, Were the Dark Ages Triggered by Volcano-Related Climate Changes in the 6th Century?

17. ^ Stothers R.B. (26 January 1984). "Mystery cloud of AD 536". Nature 307 (5949): 344–5. Bibcode 1984Natur.307..344S. doi:10.1038/307344a0. http://www.nature.com/nature/journal/v307/n5949/abs/307344a0.html.

18. ^ "Comet smashes triggered ancient famine". New Scientist. 7 January 2009. http://www.newscientist.com/article/mg20126882.900-comet-smashes-triggered-ancient-famine.html.

19. ^ Dull, R., J.R. Southon, S. Kutterolf, A. Freundt, D. Wahl, P. Sheets; Southon; Kutterolf; Freundt; Wahl; Sheets (13–17 December. 2010). "Did the TBJ Ilopango eruption cause the AD 536 event?". AGU Fall Meeting Abstracts 13: 2370. Bibcode 2010AGUFM.V13C2370D.

20. ^ Dull, R. A., Southon, J. R. & Sheets, P. (2001). "Volcanism, ecology and culture: a reassessment of the Volcán Ilopango TBJ eruption in the southern Maya realm". Latin American Antiquity 12 (1): 25–44. doi:10.2307/971755. JSTOR 971755.