Until now, researchers blamed the collapse of the Bronze Age on widespread changes in global temperatures. But now experts believe the huge population collapse, that took place in around 800BC, actually occurred two generations before this weather shift.
The team used new statistical techniques to analyse more than 2,000 radiocarbon dates, taken from hundreds of archaeological sites in Ireland, to pinpoint the precise dates that Europe’s Bronze Age population collapsed. Dunbeg Fort in Munster (pictured) is thought to date to the Bronze Age
Records show that colder and wetter weather conditions weren’t recorded until after the collapse – and social and economic pressures were more likely to blame.
Their results, published in the journal Proceedings of the National Academy of Sciences, show that human activity started to decline after 900BC, and fell rapidly after 800BC, indicating a population collapse.
However, climate records reveal that icy conditions didn’t occur until around 750BC.
Fluctuations in levels of human activity at a given time are reflected by the numbers of radiocarbon dates for a certain period.
The team used statistical techniques to analyse more than 2,000 radiocarbon dates, which they took from hundreds of archaeological sites in Ireland.
From this, they were able to pinpoint the precise dates Europe’s Bronze Age population collapsed.
The researchers then analysed climate records from peat bogs in Ireland, and compared the archaeological data to these records to see if the dates tallied.
This information was compared with evidence of climate change across Europe between 1,200BC and 500BC.
Lead author Ian Armit, Professor of Archaeology at Bradford University, said: ‘Our evidence shows definitively that the population decline in this period cannot have been caused by climate change.’
Dr Graeme Swindles, Associate Professor of Earth System Dynamics at Leeds University, added: ‘We found clear evidence for a rapid change in climate to much wetter conditions, which we were able to precisely pinpoint to 750BC using statistical methods.’
Professor Armit said social and economic stress is more likely to be the cause of the sudden and widespread fall in numbers.