An international team of geologists used annual tree rings, ice samples and records from medieval monasteries.
They managed to determine the exact dates of five powerful volcanic eruptions that occurred in the twelfth and thirteenth centuries. They are supposed to have caused the so-called “Little (or Short) Ice Age”. This was announced on Wednesday, April 5, by the press service of the Swiss University of Geneva.
“We only knew about these volcanic eruptions because their ash was preserved in the ice of Antarctica and Greenland,” said Clive Oppenheimer, a professor at the University of Cambridge in the UK. By combining this geological data with information about lunar eclipses from medieval records, we were able to get more estimates. Accuracy of where and when the most powerful volcanic eruptions occurred during this time period.”
The so-called Little Ice Age is the period of time between 1300 and 1850 AD, when the average temperature in Europe was about 0.5 degrees Celsius lower than in the previous millennium. One reason for this cooling is that during the twelfth and thirteenth centuries there was a high level of volcanic activity on Earth, as its ash spread through the earth’s atmosphere and reflected sunlight from space.
Professor Oppenheimer and his colleagues have determined exactly when six of the most powerful volcanic eruptions of this historical period occurred by analyzing ash samples preserved in ice deposits over the centuries in Greenland and Antarctica, as well as studying records of lunar eclipses made by medieval European monks and Asian monks. historians. .
It turned out that monks and historians in the Middle Ages witnessed during this time six phenomena of “bloody lunar eclipses” caused by powerful volcanic eruptions. One of them was the eruption of the Indonesian island of Samalas in 1257, already known to historians and geologists. As for the other five disasters that occurred in 1108, 1171, 1182, 1229, 1276 and 1286, they were not previously known and were not mentioned in either Western or Eastern sources.
Professor Oppenheimer and his colleagues hope that pinpointing the exact dates of these volcanoes will help geologists discover other consequences of these disasters. The researchers concluded that their follow-up study will help geologists and climatologists more accurately assess the contribution of volcanoes to the initiation of the Little Ice Age.
Source: TASS
