Rising global average temperatures due to anthropogenic global warming continue to be one of today’s major climate challenges, but the planet may also be susceptible to periods of cold and darkness, such as ice ages. I have. even small ones.
inside The climatic interval that scientists call the Little Ice Age From the early 14th century to the mid-19th century CE, the expansion of mountain glaciers reduced the global average temperature in the northern hemisphere by 1.1 °F compared to the average temperatures in 1000 and 2000. Crops fail, sunshine hours get shorter, 1816 is often called the “year without a summer”.
Scientists are still piecing together what may have caused the Little Ice Age, likely some of the largest volcanic eruptions in recorded history. A study published in the journal on April 5 Nature uses sources that seem unlikely to help put this climate puzzle together. medieval monk.
[Related: Geologists: We’re not ready for volcanoes.]
Using these 12th- and 13th-century records from Europe and the Middle East, along with tree-ring and ice-core data, an international team of researchers has pinpointed some of the largest volcanic eruptions humans have experienced. It was dated to
Over nearly five years, the team combed through hundreds of records looking for references to total lunar eclipses and their colors. Normally during a lunar eclipse, the Moon remains visible as a reddish orb because it is still shrouded in sunlight that is bent around the Earth by the atmosphere. But after a major volcanic eruption on Earth, there could be so much dust in the stratosphere that the eclipsed Moon would disappear almost completely.
Medieval meticulous record-keepers recorded everything from major acts of popes and kings, important battles, natural disasters, and celestial events. Some believed that what was happening in the sky could bring disaster to the earth. Medieval monks kept the biblical book of Revelation in mind. Including a blood-red moonBetween 1100 and 1300, 64 Total Lunar Eclipses Over Europe And the recorders observed in this study faithfully recorded 51 of them. In his five of these eclipses, they also noticed that the moon was very dark.
“While listening to Pink Floyd’s ‘Dark Side of the Moon’ album, I realized that all of the darkest lunar eclipses occurred within a year or so of a massive volcanic eruption.” and study co-author Sébastien Guillet, paleoclimatologist and physical geographer at the University of Geneva said in a statement“Now that we know the exact date of the eclipse, it opens up the possibility of using sightings to narrow down when the eruption must have occurred.”
[Related: Researchers found what they believe is a 2,000-year-old map of the stars.]
Looking at records outside of Europe and the Middle East, the team found that Japanese chroniclers also recorded lunar eclipses.a famous scribe and poet named Teika Fujiwara Described an unprecedented dark eclipse observed on December 2, 1229. I have written “People in the olden days could not see the position of the lunar disk, as if the moon had disappeared during a lunar eclipse, and had never seen it like this time…it was truly terrifying.”
These “unprecedented” eclipsed stratospheric dust not only obscured the Moon, but also lowered summer temperatures by limiting the amount of sunlight reaching the surface.
“Previous studies show that powerful tropical eruptions can cause a global cooling of about 1°C. [2.0°F] Markus Stoffel, co-author of the study, geoscientist and climatologist at the University of Geneva said in a statement“It can also lead to anomalous rainfall, such as drought in one place and flooding in another.” , who co-designed this study.
At the time, it would have been difficult or impossible for scientists and the general public to link crop failures due to lack of sunlight to volcanic eruptions.
“We knew about these eruptions only because they left traces in the ice of Antarctica and Greenland,” said study co-author Clive Oppenheimer, a volcanologist at the University of Cambridge. in a statement“Combining information from ice cores with accounts from medieval texts has allowed us to make more accurate estimates of when and where some of the largest eruptions of this period occurred.”
The team worked with climate modelers to calculate the likely timing of these eruptions. Seasons affected by volcanoes How did volcanic ash spread? Modeling helped narrow down the timing and intensity of volcanic events.
According to the team, the time interval from 1100 to 1300 is A particularly active period in volcanic history Thanks to evidence from ice cores. Knowing more about this period is crucial to understanding the impact of volcanoes on society and the planet.
