Study: Climate change contributed to rise and fall of Roman empire

Some House Democrats blamed their defeat in November’s midterm elections partly on Speaker Nancy Pelosi's decision to force a vote on a climate change bill. A new study suggests that climate change has claimed bigger political victims in the past. Much bigger.

The study published in the journal Science suggests climate change contributed to the rise and fall of the Roman empire.

“Climate change seems a factor in the rise and fall of the Roman empire, according to a study of ancient tree growth that urges greater awareness of the risks of global warming in the 21st century,” Reuters reports.

The study's lead author said climate shifts affected farming and amplified other political, social and economic crises.

The study notes that periods of good oak and pine growth in central Europe over the last 2,500 years signaled warm, wet summers that overlapped with wealthy periods among farming societies — including the height of the Roman empire.

But the story notes that the good times didn’t last: “Periods of climate instability overlapped with political turmoil, such as during the decline of the Roman empire, and might even have made Europeans vulnerable to the Black Death or help explain migration to America during the chill 17th century.”

There was a lot of discussion after last November’s midterms about whether votes for cap-and-trade fueled the defeat of some House lawmakers. Democrats lost 63 House seats — many of those who lost supported a climate change bill approved by the House.