Changes in climate have played a huge role in European history, influencing or even causing events like the decline of Rome and the Black Death, according to researchers studying ancient tree growth. Tree-ring samples from nearly 9,000 of pieces of wood collected over 30 years reveal that a stable climate coincided with periods of prosperity, while climate shifts overlapped with turmoil, Science reports.
The Black Death occurred during a period of unstable, wet weather that provided ideal conditions for plague to spread, say researchers. Likewise, "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," read the report. Climate shifts that affected agriculture end up "amplifying political, social and economic crises," the lead researcher tells Reuters. The research, he added, "may challenge recent political and fiscal reluctance" to tackle climate change in the 21st century," especially since the degree of climate change occurring now is more severe than anything seen in the 2,500-year period studied.