Ice one: Snow fell on Baghdad in 2008 for the first time in memory Temperatures in Baghdad range from around 2C in winter to 45C in the summer – but ancient Arabic writings have revealed that the city experienced a dramatic frozen period around 1,000 years ago .
Spanish researchers from the University of Extremadura found 9th and 10th century (3rd and 4th in the Islamic calendar) sources that refer to snowfalls in the Iraqi capital in 908, 944 and 1007 and even rivers being frozen.
These are extreme events for Baghdad - for example, the only snowfall in the modern era took place in 2008 - and help meteorologists better understand today's climate.
Lead author Dr Fernando Domínguez-Castro, writing in the journal Weather, said: ‘Climate information recovered from these ancient sources mainly refers to extreme events which impacted wider society such as droughts and floods.
‘However, they also document conditions which were rarely experienced in ancient Baghdad such as hailstorms, the freezing of rivers or even cases of snow.
‘These signs of a sudden cold period confirm suggestions of a temperature drop during the tenth century, immediately before the Medieval Warm Period.
‘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.’
The study provides valuable information for scientists looking at how the Earth’s climate is changing over long periods of time and extra context for modern weather patterns.
Domínguez-Castro added: ‘Ancient Arabic documentary sources are a very useful tool for finding eye witness descriptions which support the theories made by climate models. The ability to reconstruct past climates provides us with useful historical context for understanding our own climate.’