Volcanic Eruption(s) and the Bubonic Plague Pandemic of 1346-1353 CE

[Astronuc]

The Black Death was a bubonic plague pandemic that occurred in Europe from 1346 to 1353.

https://en.wikipedia.org/wiki/Black_Death

A volcanic eruption may have catalyzed the plague's arrival in Europe, study suggests​

New research suggests a volcanic eruption around 1345 cooled the climate, leading to crop failures. On the ships that carried imported grain to fill the gap came plague-carrying fleas.

https://www.nbcnews.com/science/science-news/volcanic-eruption-plague-europe-study-rcna247222

The theory, described in a study published Thursday in the journal Communications Earth & Environment, suggests the eruptions set off a series of events that enabled the fleas that spread the plague to proliferate in Europe.

The eruptions dimmed global temperatures for a few years, causing a sudden climate shift that affected harvests in Europe. With crops failing and fears of starvation rising, some wealthy Italian city-states like Florence and Venice imported grain from elsewhere in the world. And on those ships most likely came plague-infected fleas.

Volcanic eruption may have triggered Europe's deadly Black Death plague​

https://www.bbc.com/news/articles/cy5gr2x914ro

The Nature Communications: Earth & Environment article: Climate-driven changes in Mediterranean grain trade mitigated famine but introduced the Black Death to medieval Europe

In the article is a statement, "little effort has been made to evaluate the climate response and societal consequence of a yet unidentified but likely tropical volcanic eruption – or cluster of eruptions – around 1345 CE". That is followed by "the volcanic stratospheric sulphur injection in 1345 CE amounts to an estimated 14 Teragram (Tg)" and "The climate-relevant signal in 1345 CE ranks 18 over the past 2000 years and was preceded by at least three volcanic eruptions in circa 1329, 1336 and 1341 CE. The reconstructed sulphur injections of these events are circa 3.7, 0.7 and 1.2 Tg, and the first and last eruption likely occurred in the Northern Hemisphere extra-tropics."

Presumably, there is evidence of such volcanic activity - somewhere. There is the challenge that there appears to have been two sets of volcanic activity, vis-à-vis, the references to "likely tropical volcanic eruption" and "the first and last eruption likely occurred in the Northern Hemisphere extra-tropics."

Tropical volcanic activity could be in Indonesia, Philippines, or somewhere along the western Pacific Ring-of-Fire, and from Mexico through Central America and down into South America (Andean Volcanoes), and perhaps one or more Caribbean volcanoes.

The extra-tropical volcano could be one of the California volcanoes, Cascade volcanoes, Alaskan volcanoes, Russian/Siberian volcanoes, or perhaps Iceland.

In the case of the Justiniam plague, it is through that an Icelandic volcano is a potential cause of the cold summer in 536.
https://en.wikipedia.org/wiki/Volcanic_winter_of_536. However,

"Geochemical analysis of AD 536 cryptotephras distinguishes at least three synchronous eruptive events in North America. Further analysis correlates one of the eruptions to a widespread Mono Craters tephra identified in northeast California. The other two eruptions most likely originated from the eastern Aleutians and Northern Cordilleran volcanic province."

https://en.wikipedia.org/wiki/Plague_of_Justinian

So where is the geological or paleoarcheological evidence for volcanic eruptions in 534 - 536 CE and 1329, 1336, 1341 and 1345 CE? What about in between, or since?

Meanwhile - Researchers have found that the cooling effect that volcanic eruptions have on Earth's surface temperature is likely underestimated by a factor of two, and potentially as much as a factor of four, in standard climate projections.
https://www.cam.ac.uk/research/news...icantly-underestimated-in-climate-projections

VOLCANIC ERUPTIONS AND CLIMATE (Robock, 2000)
https://climate.envsci.rutgers.edu/pdf/ROG2000.pdf

Note that volcanic eruptions are transient events as are the climate impacts/consequences.
https://www.usgs.gov/programs/VHP/volcanoes-can-affect-climate

 

[BWV]

More generally, multiple late 13th century eruptions are thought responsible for the end of the Medieval warm period and beginning of the little ice age. The widespread famine from 1315-22 made populations more vulnerable to the plague when it arrived

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2011GL050168

 

[Baluncore]

So where is the geological or paleoarcheological evidence for volcanic eruptions in 534 - 536 CE and 1329, 1336, 1341 and 1345 CE? What about in between, or since?

I expect those accurate dates come from Greenland ice cores, with temperatures from tree rings. The question of geographical attribution to a particular volcanic event is the difficult part.

The tephra will be sorted by transport mechanism, time, and distance, so dust in one place will be different to dust from the same event, deposited in another place.

While it is interesting, I wonder how much it really matters, where the dust came from. The early phases of an eruption are often obscured or erased by later phases, or by subsequent events.