Trees, coral, and ice cores provide us a very reliable method of looking at the past climate, but there isn’t as much human recorded data. New research has analysed scholarly writings from Iraq written during the Islamic Golden Age between 816 and 1009 AD in an effort to reveal more information about our planet’s historical climate.
Published in the journal Weather, the Spanish researchers from the University of Extremadura looked at the writings of scholars, historians, and diarists from Iraq. The sources focused primarily on social and religious events of the time, but naturally the rare and abnormal weather was documented when it happened.
“Climate information recovered from these ancient sources mainly refers to extreme events which impacted wider society such as droughts and floods,” said lead author Dr Fernando Domínguez-Castro. “However, they also document conditions which were rarely experienced in ancient Baghdad such as hailstorms, the freezing of rivers or even cases of snow.”
For example, writings from al-Tabari (913 AD), Ibn al-Athir (1233 AD) and al-Suyuti (1505 AD) were studied and showed that there was an increase of cold events in the first half of the 10th century, including a significant drop in temperature during July 920 AD, and three separate recordings of snowfall in 908, 944, and 1007.
For comparison, the only record of snow in modern Baghdad was in 2008.
“These signs of a sudden cold period confirm suggestions of a temperature drop during the tenth century, immediately before the Medieval Warm Period,” said Domínguez-Castro. “We believe the drop in July 920 AD may have been linked to a great volcanic eruption but more work would be necessary to confirm this idea.”
Subsequently the research team believe that Iraq experienced a greater frequency of significant climate events and severe cold weather than it does today.
“Ancient Arabic documentary sources are a very useful tool for finding eye witness descriptions which support the theories made by climate models,” said Domínguez-Castro. “The ability to reconstruct past climates provides us with useful historical context for understanding our own climate. We hope this potential will encourage Arabic historians and climatologists to work together to increase the climate data rescued from across the Islamic world.”