Ours is not the first civilisation to be threatened by climate change, scientists have established. It could also have been responsible for bringing down the Roman Empire.
Researchers who used tree growth rings to study the impact of unstable climate patterns found that they could be linked to historical events that have had devastating consequences.
Researchers who used tree growth rings to study climate patterns found that they could be matched to historical events that had devastating consequences.
Scientists discovered that periods of warm, wet weather coincided with prosperity while dry or varying conditions occurred at times of political turmoil, such as the fall of the Roman Empire and the Thirty Years' War.
The researchers reconstructed the history of European summer climate for the last 2,500 years using 9,000 wooden artefacts.
Their results are based on measurements of tree-rings from the sub-fossil, archaeological, historical and living tree samples from Germany, France, Italy and Austria.
During good seasons, when water and nutrients were in plentiful supply, they found that trees formed broad rings.
But in less favourable growing conditions, the rings grew in much tighter formation.
The team of archaeologists, climatologists, geographers and historians then identified a link with prosperity levels in past societies.
“Wet and warm summers occurred during periods of Roman and medieval prosperity,” they wrote on the Science journal website.
“Increased climate variability from 250-600AD coincided with the demise of the western Roman empire and the turmoil of the migration period.
“Distinct drying in the 3rd Century paralleled a period of serious crisis in the western Roman empire marked by barbarian invasion, political turmoil and economic dislocation in several provinces of Gaul.”
They also found that increased humidity was a perfect breeding ground for rodents during the plague.
Mr Buntgen noted that the results could help to build on future climate models and also act as a warning of how variations may affect society.
He said: "Our results will help us to be more cautious, taking into account that our modern civilisation is not immune to climate change.
"For example, we can project it is likely that changes in precipitation and spatial redistribution of this will result in increased drought, which will impact our society – perhaps with migration and conflict due to limited water resources.
"We are very interested in understanding past civilisations and making our research more dense.
"There is room for improvement to get higher quality data and over a larger timescale.”