Medieval Iceland Volcanic Eruptions Triggered Black Sea Icebergs, Study Finds

An international study led by researchers from the University of Bern and the Austrian Academy of Sciences has revealed that volcanic eruptions in medieval Iceland triggered the formation of icebergs in the southwestern Black Sea near present-day Istanbul. The findings challenge previous assumptions about dormant phases in the region's history.

The study, published recently, provides compelling evidence that these volcanic eruptions had a significant impact on the climate and environment in the area, leading to the presence of icebergs in a location not typically associated with such phenomena. By analyzing traces of volcanic ash, known as cryptotephra, the researchers discovered a prolonged episode of volcanic sulfur dioxide emissions between AD 751 and 940, primarily attributed to the eruptions of Iceland's Katla volcano from AD 751 to 763.

Why this matters: The study sheds new light on the complex relationship between volcanic activity, climate change, and environmental conditions in the past. The findings have important implications for our understanding of the region's history and the factors that shaped it, highlighting the far-reaching effects of volcanic eruptions on distant locations.

The researchers conclude that the winter of AD 763 was so cold that parts of the Black Sea, north of what was then the city of Constantinople, were covered in ice. Historical sources from the period describe the extreme cold causing animal deaths and crop failures, leading to immediate hardship and affecting people on various levels.

Dr. Markus Stoffel, a professor at the University of Bern and co-author of the study, emphasized the significance of the findings: "This study shows that these extreme climate fluctuations also affected early medieval society. It underscores the importance of understanding the complex interplay between volcanic activity and climate change in shaping our past and present."

Key Takeaways

• Medieval Icelandic volcanic eruptions caused icebergs in the Black Sea.
• Volcanic sulfur dioxide emissions from Katla volcano (751-763 AD) impacted climate.
• Extreme cold in 763 AD led to animal deaths and crop failures.
• Study challenges assumptions about the region's dormant climate history.
• Findings highlight complex interplay between volcanoes and climate change.