Ancient Arabic Manuscripts Help Scientists Reconstruct Past Climate

Scientists have been able to reconstruct abnormal climate patterns that occurred during the 9th and 10th centuries in Iraq by examining and analyzing ancient manuscripts written by Islamic writers during the Islamic Golden Age.

The research, conducted by a team of scientists led by Dr Fernando Domínguez-Castro and published in Weather, examined writings of scholars, historians and diarists in Iraq between 816-1009 AD for evidence of unusual weather patterns.

"Climate information recovered from these ancient sources mainly refers to extreme events which impacted wider society such as droughts and floods," said 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."

The manuscripts documented an increase of cold weather occurrences in the first half of the 10th century, including a sharp drop in temperatures during July 920 AD and three incidents of snowfall in 908, 944 and 1007. The only other record of snow occurred in modern Baghdad 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."

Scientists believe that reconstructing climates from the past provides a valuable historical and contextual comparison for understanding modern weather events and climate change. By collecting data from such natural sources as tree rings, coral and ice cores, researchers have been able to glean clues to weather patterns and climate changes of the past. But this study has provided an example of how historical, political and religious documents of the past can contribute, in a significant way, to this kind of research.

"Ancient Arabic documentary sources are a very useful tool for finding eye witness descriptions which support the theories made by climate models," added 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."

The details of the study are published in the journal, Weather: F. Dominguez-Castro, J. M. Vaquero, M. Marin, M. C. Gallego, R. Garcia-Herrera, “How useful could Arabic documentary sources be for reconstructing past climate,” Weather, Wiley-Blackwell, DOI: 10.1002/wea.835
http://popular-archaeology.com/issue/december-2011/article/ancient-arabic-manuscripts-help-scientists-reconstruct-past-climate