BBC News is reporting that new scientific research on tree rings shows some remarkable correlations with the ebb and flow of civilizations:
An extensive study of tree growth rings says there could be a link between the rise and fall of past civilisations and sudden shifts in Europe’s climate.
A team of researchers based their findings on data from 9,000 wooden artifacts from the past 2,500 years.
They found that periods of warm, wet summers coincided with prosperity, while political turmoil occurred during times of climate instability.
The findings have been published online by the journal Science.
“Looking back on 2,500 years, there are examples where climate change impacted human history,” co-author Ulf Buntgen, a paleoclimatologist at the Swiss Federal Research Institute for Forest, Snow and Landscape, told the Science website.
The team capitalised on a system used to date material unearthed during excavations.
“Archaeologists have developed oak ring width chronologies from Central Europe that cover nearly the entire Holocene and have used them for the purpose of dating artefacts, historical buildings, antique artwork and furniture,” they wrote.
“Chronologies of living and relict oaks may reflect distinct patterns of summer precipitation and drought.”
The team looked at how weather over the past couple of centuries affected living trees’ growth rings.
During good growing seasons, when water and nutrients are in plentiful supply, trees form broad rings, with their boundaries relatively far apart.
But in unfavourable conditions, such as drought, the rings grow in much tighter formation.
The researchers then used this data to reconstruct annual weather patterns from the growth rings preserved in the artefacts.
Once they had developed a chronology stretching back over the past 2,500 years, they identified a link with prosperity levels in past societies, such as the Roman Empire…
[continues at BBC News]