Climate change ruled out as cause of Bronze Age population collapse
Human activity began to decline after 900 BC, and to fall rapidly after 800 BC.
But archaeologists and environmental scientists from the University of Bradford, University of Leeds, University College Cork, Ireland (UCC), and Queen's University Belfast now say that colder, wetter conditions didn't occur until around two generations later.
The team then analysed past climate records from peat bogs in Ireland and compared the archaeological data to these climate records to see if the dates tallied. That information was then compared with evidence of climate change across NW Europe between 1200 and 500 BC.
"Our evidence shows definitively that the population decline in this period cannot have been caused by climate change," says Ian Armit, Professor of Archaeology at the University of Bradford, and lead author of the study.
According to Professor Armit, social and economic stress is more likely to be the cause of the sudden and widespread fall in numbers as trading networks in vital resources such as copper and tin were disrupted. This may have led to conflict and social collapse, he says.
Climate may still have played a role, however.
"Although climate change was not directly responsible for the collapse it is likely that the poor climatic conditions would have affected farming," Professor Armit said. "This would have been particularly difficult for vulnerable communities, preventing population recovery for several centuries."
The results are published this week in Proceedings of the National Academy of Science