Did violent volcanoes in Russia, Greenland and Alaska affect the lives of ancient Egyptians?
It may sound improbable, but according to a new study, the answer is yes.
In a paper published Tuesday in Nature Communications, a team of researchers shows that explosive volcanic eruptions in high northern latitudes of the globe can impact the Nile watershed, causing the flow of one of the world's mightiest rivers to slow.
This in turn could keep the lower Nile from flooding in the late summer months -- a regular occurrence on which ancient Egyptians relied to irrigate their crops.
No Nile flooding meant no irrigation, which meant a bad year in the fields, low food supplies and ultimately, researchers say, civic unrest.
"It's a bizarre concept that Alaskan volcanoes were screwing up the Nile, but in fact, that's what happened," said Joseph Manning, a historian at Yale University who worked on the study.
Manning said the idea to compare geological evidence of volcanoes with records kept by the ancient Egyptians occurred to him about two years ago.
He was at a dinner with geographer Francis Ludlow, now at Trinity College in Dublin, who had contributed to a seminal study that redated volcanic eruptions and looked at how they may have impacted the climate -- and history -- at the time.
Around their third glass of wine, Manning asked Ludlow whether he had any data on volcanoes that erupted from 305 to 30 B.C. -- the centuries that the powerful Ptolemaic dynasty ruled Egypt, and Manning's area of expertise.
When Ludlow pulled the data up on his computer, Manning was stunned. He instantly recognized the dates of some of the volcanoes as corresponding with times of upheaval in Ptolemaic Egypt.