Led by University of Geneva paleoclimatologist Dr. “They can also lead to rainfall anomalies with droughts in one place and floods in another.” Markus Stoffel (PhD), University of Geneva (UNIGE) researcher and senior author on the paper. “We know from previous work that strong tropical eruptions can induce global cooling on the order of roughly 1☌, over a few years,” said Dr. When volcanoes erupt, spewing ash and sulfur into the atmosphere, the resulting haze can decrease the intensity of sunlight reaching the surface, cooling global temperatures over a period of years. “Volcanic eruptions are really important for understanding past climate variability-eclipse observations can be used to help determine the timing of past eruptions, many of which are otherwise only known of because of the chemical markers in polar ice cores.” Matthew Toohey (PhD), assistant professor in the Department of Physics and Engineering Physics in the USask College of Arts and Science, and co-author of the paper. “This work is a really novel example of interdisciplinary research, bringing together threads of evidence from medieval history, paleoclimatology and atmospheric physics,” said Dr. Of 64 lunar eclipses that occurred in Europe during that period, monks described 51, noting five were especially dark-something which can occur when dust from major volcanic eruptions is present in the stratosphere. The interdisciplinary research published today in the journal Nature examined astronomical records from monks and chroniclers across Europe, the Middle East, and Asia from the High Medieval Period (1100–1300 CE), a volcanically-active period.

Medieval illuminations eclipse