Climate changes of 535–536
Encyclopedia
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. The event is thought to have been caused by an extensive atmospheric dust veil, possibly resulting from a large volcanic eruption in the tropics, or debris from space impacting the Earth. Its effects were widespread, causing unseasonal weather, crop failures, and famine
s worldwide.
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."
The Gaelic Irish Annals
record the following:
Further phenomena reported by a number of independent contemporary sources:
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. Similar patterns are recorded in tree rings from Sweden
and Finland
, in California's
Sierra Nevada and in rings from Chile
an Fitzroya
trees. Ice core
s from Greenland
and Antarctica show evidence of substantial sulfate
deposits around 533–534 ± 2 years, evidence of an extensive acidic dust veil.
or meteorite
, or after the eruption of a volcano
(a phenomenon known as "volcanic winter
"). 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
.
In 1984, R. B. Stothers postulated that this event might have been caused by the volcano Rabaul
in what is now Papua New Guinea
.
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 Indonesia
n volcano Krakatoa
exploded at the time and caused the changes. 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.
In 2009, Dallas Abbott
of Columbia University's Lamont-Doherty Earth Observatory in New York published evidence from Greenland ice core
s 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.
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. Although earlier published radiocarbon evidence suggested a two-sigma age range of AD 408–536, 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. 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.
, possibly to appease the angry gods and get the sunlight back.
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 Mongolia
n tribes towards the West, the end of the Persian Empire, the rise of Islam
, and the fall of Teotihuacán
. 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. 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."
Northern Hemisphere
The Northern Hemisphere is the half of a planet that is north of its equator—the word hemisphere literally means “half sphere”. It is also that half of the celestial sphere north of the celestial equator...
in the last 2,000 years. The event is thought to have been caused by an extensive atmospheric dust veil, possibly resulting from a large volcanic eruption in the tropics, or debris from space impacting the Earth. Its effects were widespread, causing unseasonal weather, crop failures, and famine
Famine
A famine is a widespread scarcity of food, caused by several factors including crop failure, overpopulation, or government policies. This phenomenon is usually accompanied or followed by regional malnutrition, starvation, epidemic, and increased mortality. Every continent in the world has...
s worldwide.
Documentary evidence
The ByzantineByzantine Empire
The Byzantine Empire was the Eastern Roman Empire during the periods of Late Antiquity and the Middle Ages, centred on the capital of Constantinople. Known simply as the Roman Empire or Romania to its inhabitants and neighbours, the Empire was the direct continuation of the Ancient Roman State...
historian Procopius
Procopius
Procopius of Caesarea was a prominent Byzantine scholar from Palestine. Accompanying the general Belisarius in the wars of the Emperor Justinian I, he became the principal historian of the 6th century, writing the Wars of Justinian, the Buildings of Justinian and the celebrated Secret History...
recorded of 536, in his report on the wars with the Vandals
Vandals
The Vandals were an East Germanic tribe that entered the late Roman Empire during the 5th century. The Vandals under king Genseric entered Africa in 429 and by 439 established a kingdom which included the Roman Africa province, besides the islands of Sicily, Corsica, Sardinia and the Balearics....
, "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."
The Gaelic Irish Annals
Irish annals
A number of Irish annals were compiled up to and shortly after the end of Gaelic Ireland in the 17th century.Annals were originally a means by which monks determined the yearly chronology of feast days...
record the following:
- "A failure of bread in the year 536 AD"—The Annals of UlsterAnnals of UlsterThe Annals of Ulster are annals of medieval Ireland. The entries span the years between AD 431 to AD 1540. The entries up to AD 1489 were compiled in the late 15th century by the scribe Ruaidhrí Ó Luinín, under his patron Cathal Óg Mac Maghnusa on the island of Belle Isle on Lough Erne in the...
- "A failure of bread from the years 536–539 AD"—The Annals of InisfallenAnnals of InisfallenThe Annals of Inisfallen are a chronicle of the medieval history of Ireland. There are more than 2,500 entries spanning the years between AD 433 and AD 1450, but it is believed to have been written between the 12th and 15th centuries...
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)
- Crop failures
- "A dense, dry fog" in the Middle East, China, and Europe
- Drought in Peru, which affected the MocheMoche'The Moche civilization flourished in northern Peru from about 100 AD to 800 AD, during the Regional Development Epoch. While this issue is the subject of some debate, many scholars contend that the Moche were not politically organized as a monolithic empire or state...
culture
Scientific evidence
Tree ring analysis by dendrochronologistDendrochronology
Dendrochronology or tree-ring dating is the scientific method of dating based on the analysis of patterns of tree-rings. Dendrochronology can date the time at which tree rings were formed, in many types of wood, to the exact calendar year...
Mike Baillie
Mike Baillie
Mike Baillie is a Professor Emeritus of Palaeoecology at Queen's University of Belfast, in Northern Ireland. Baillie is a leading expert in dendrochronology, or dating by means of tree-rings...
, of the Queen's University of Belfast
Queen's University of Belfast
Queen's University Belfast is a public research university in Belfast, Northern Ireland. The university's official title, per its charter, is the Queen's University of Belfast. It is often referred to simply as Queen's, or by the abbreviation QUB...
, shows abnormally little growth in Irish oak in 536 and another sharp drop in 542, after a partial recovery. Similar patterns are recorded in tree rings from Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
and Finland
Finland
Finland , officially the Republic of Finland, is a Nordic country situated in the Fennoscandian region of Northern Europe. It is bordered by Sweden in the west, Norway in the north and Russia in the east, while Estonia lies to its south across the Gulf of Finland.Around 5.4 million people reside...
, in California's
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
Sierra Nevada and in rings from Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
an Fitzroya
Fitzroya
Fitzroya is a monotypic genus in the cypress family.-Species:The single living species, Fitzroya cupressoides, is a tall, long-lived conifer native to the Andes mountains of southern Chile and Argentina, where it is an important member of the Valdivian temperate rain forests...
trees. Ice core
Ice core
An ice core is a core sample that is typically removed from an ice sheet, most commonly from the polar ice caps of Antarctica, Greenland or from high mountain glaciers elsewhere. As the ice forms from the incremental build up of annual layers of snow, lower layers are older than upper, and an ice...
s from Greenland
Greenland
Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...
and Antarctica show evidence of substantial sulfate
Sulfate
In inorganic chemistry, a sulfate is a salt of sulfuric acid.-Chemical properties:...
deposits around 533–534 ± 2 years, evidence of an extensive acidic dust veil.
Possible explanations
It has been conjectured that these changes were due to ashes or dust thrown into the air after the impact of a cometComet
A comet is an icy small Solar System body that, when close enough to the Sun, displays a visible coma and sometimes also a tail. These phenomena are both due to the effects of solar radiation and the solar wind upon the nucleus of the comet...
or meteorite
Meteorite
A meteorite is a natural object originating in outer space that survives impact with the Earth's surface. Meteorites can be big or small. Most meteorites derive from small astronomical objects called meteoroids, but they are also sometimes produced by impacts of asteroids...
, or after the eruption of a volcano
Volcano
2. Bedrock3. Conduit 4. Base5. Sill6. Dike7. Layers of ash emitted by the volcano8. Flank| 9. Layers of lava emitted by the volcano10. Throat11. Parasitic cone12. Lava flow13. Vent14. Crater15...
(a phenomenon known as "volcanic winter
Volcanic winter
A volcanic winter is the reduction in temperature caused by volcanic ash and droplets of sulfuric acid obscuring the sun and raising Earth's albedo after a large particularly explosive type of volcanic eruption...
"). 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
Year Without a Summer
The Year Without a Summer was 1816, in which severe summer climate abnormalities caused average global temperatures to decrease by about 0.4–0.7 °C , resulting in major food shortages across the Northern Hemisphere...
", which has been connected to the explosion of the volcano Mount Tambora
Mount Tambora
Mount Tambora is an active stratovolcano, also known as a composite volcano, on the island of Sumbawa, Indonesia. Sumbawa is flanked both to the north and south by oceanic crust, and Tambora was formed by the active subduction zone beneath it. This raised Mount Tambora as high as , making it...
in Sumbawa
Sumbawa
Sumbawa is an Indonesian island, located in the middle of the Lesser Sunda Islands chain, with Lombok to the west, Flores to the east, and Sumba further to the southeast. It is in the province of West Nusa Tenggara....
, Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
.
In 1984, R. B. Stothers postulated that this event might have been caused by the volcano Rabaul
Rabaul caldera
Rabaul caldera is a large volcano situated in East New Britain, Papua New Guinea. It derives its name from the town of Rabaul situated inside the caldera. The highest of its multiple peaks is ....
in what is now Papua New Guinea
Papua New Guinea
Papua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands...
.
In 1999, David Keys
David Keys (author)
David Keys is archaeology correspondent for the London daily paper, The Independent, frequent television commentator on archaeological matters and author of the 1999 book Catastrophe: An Investigation into the Origins of the Modern World. He has visited over a thousand archaeological sites in sixty...
in his book Catastrophe: A Quest for the Origins of the Modern World (supported by work of the American volcanologist
Volcanology
Volcanology is the study of volcanoes, lava, magma, and related geological, geophysical and geochemical phenomena. The term volcanology is derived from the Latin word vulcan. Vulcan was the ancient Roman god of fire....
Ken Wohletz), suggested that the Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
n volcano Krakatoa
Krakatoa
Krakatoa is a volcanic island made of a'a lava in the Sunda Strait between the islands of Java and Sumatra in Indonesia. The name is used for the island group, the main island , and the volcano as a whole. The island exploded in 1883, killing approximately 40,000 people, although some estimates...
exploded at the time and caused the changes. It is suggested that an eruption of Krakatoa attributed to the year 416 by the Javanese Book of Kings
Pararaton
The Pararaton, also known as the Book of Kings, is a manuscript in the Kawi language. The comparatively short text of 32 folio-size pages contains the history of the kings of Singhasari and Majapahit in eastern Java...
actually took place at this time–there is no other evidence of such an eruption in 416.
In 2009, Dallas Abbott
Dallas Abbott
Dallas Abbott is a research scientist at the Lamont-Doherty Earth Observatory of Columbia University and is part of the Holocene Impact Working Group. The primary focus of her present research is on submarine impact craters and their contribution to climate change and megatsunamis...
of Columbia University's Lamont-Doherty Earth Observatory in New York published evidence from Greenland ice core
Ice core
An ice core is a core sample that is typically removed from an ice sheet, most commonly from the polar ice caps of Antarctica, Greenland or from high mountain glaciers elsewhere. As the ice forms from the incremental build up of annual layers of snow, lower layers are older than upper, and an ice...
s 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.
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. Although earlier published radiocarbon evidence suggested a two-sigma age range of AD 408–536, 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. 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 PeriodMigration Period
The Migration Period, also called the Barbarian Invasions , was a period of intensified human migration in Europe that occurred from c. 400 to 800 CE. This period marked the transition from Late Antiquity to the Early Middle Ages...
, possibly to appease the angry gods and get the sunlight back.
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
Plague of Justinian
The Plague of Justinian was a pandemic that afflicted the Eastern Roman Empire , including its capital Constantinople, in 541–542 AD. It was one of the greatest plagues in history. The most commonly accepted cause of the pandemic is bubonic plague, which later became infamous for either causing or...
, the decline of the Avars
Eurasian Avars
The Eurasian Avars or Ancient Avars were a highly organized nomadic confederacy of mixed origins. They were ruled by a khagan, who was surrounded by a tight-knit entourage of nomad warriors, an organization characteristic of Turko-Mongol groups...
, the migration of Mongolia
Mongolia
Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest...
n tribes towards the West, the end of the Persian Empire, the rise of Islam
Islam
Islam . The most common are and . : Arabic pronunciation varies regionally. The first vowel ranges from ~~. The second vowel ranges from ~~~...
, and the fall of Teotihuacán
Teotihuacán
Teotihuacan – also written Teotihuacán, with a Spanish orthographic accent on the last syllable – is an enormous archaeological site in the Basin of Mexico, just 30 miles northeast of Mexico City, containing some of the largest pyramidal structures built in the pre-Columbian Americas...
. In 2000, a 3BM Television production (for WNET
WNET
WNET, channel 13 is a non-commercial educational public television station licensed to Newark, New Jersey. With its signal covering the New York metropolitan area, WNET is a primary station of the Public Broadcasting Service and a primary provider of PBS programming...
and Channel Four
Channel 4
Channel 4 is a British public-service television broadcaster which began working on 2 November 1982. Although largely commercially self-funded, it is ultimately publicly owned; originally a subsidiary of the Independent Broadcasting Authority , the station is now owned and operated by the Channel...
) 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
Secrets of the Dead
Secrets of the Dead is a PBS television series produced by Thirteen/WNET New York. The show generally follows an investigator or team of investigators exploring what modern science can tell us about some of the great mysteries of history...
series. However, Keys and Wohletz' ideas are not widely accepted at this point. 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."
See also
- Plague of JustinianPlague of JustinianThe Plague of Justinian was a pandemic that afflicted the Eastern Roman Empire , including its capital Constantinople, in 541–542 AD. It was one of the greatest plagues in history. The most commonly accepted cause of the pandemic is bubonic plague, which later became infamous for either causing or...
- Great Famine of 1315–1317Great Famine of 1315–1317The Great Famine of 1315–1317 was the first of a series of large scale crises that struck Northern Europe early in the fourteenth century...
- KuwaeKuwaeKuwae is a submarine caldera between Epi and Tongoa islands. Kuwae Caldera cuts through the flank of the Tavani Ruru volcano on Epi and the northwest end of Tongoa....
, a South Pacific volcano implicated in events surrounding the Fall of ConstantinopleFall of ConstantinopleThe Fall of Constantinople was the capture of the capital of the Byzantine Empire, which occurred after a siege by the Ottoman Empire, under the command of Ottoman Sultan Mehmed II, against the defending army commanded by Byzantine Emperor Constantine XI...
in 1453. - Year Without a SummerYear Without a SummerThe Year Without a Summer was 1816, in which severe summer climate abnormalities caused average global temperatures to decrease by about 0.4–0.7 °C , resulting in major food shortages across the Northern Hemisphere...
, 1816 - Minoan eruption
Further reading
- Levy, David (ed.), The Scientific American Book of the Cosmos, ISBN 0312254539, 2000, (Google Print, p. 186)
External links
- "536 and all that", from Real Climate, March 2008.
- CCNet Debate: The Ad 536-540 Mystery: Global Catastrophe, Regional Event or Modern Myth?