March 19 (UPI) -- One Iceland's most famous ancient poems describes the eruption of the Eldgjá volcano, linking the apocalyptic conditions -- the thick haze of gas and massive lava flows -- with the abandonment of the pagan gods and the acceptance of a new, singular god.
Now, researchers have pinpointed the timing of the eruption described by the epic poem, Voluspá, the "prophecy of the seeress."
Researchers in Europe collected and analyzed ice cores from Greenland, which trapped evidence of the ash emitted by Eldgjá. The data, detailed in the journal Climate Change, suggests the volcanic eruption began in the spring of 939 AD and lasted until at least the fall of 940 AD -- less than a century after the Vikings and Celts first settled the island.
"This places the eruption squarely within the experience of the first two or three generations of Iceland's settlers," Clive Oppenheimer, a geographer at the University of Cambridge, said in a news release. "Some of the first wave of migrants to Iceland, brought over as children, may well have witnessed the eruption."
Iceland specializes in a type of volcanic eruption known as a lava flood. The Eldgjá lava flood featured huge lava flows, which spread out across much of southern Iceland. A thick haze of sulphuric gases hung over the island.
Analysis of tree rings across the Northern Hemisphere suggests the haze from the Eldgjá eruption spread out across Europe and Asia, reducing sunlight and altering the global climate patterns.
"In 940, summer cooling was most pronounced in Central Europe, Scandinavia, the Canadian Rockies, Alaska and Central Asia, with summer average temperatures 2 degrees Celsius lower," said Markus Stoffel, an earth science professor at the University of Geneva.
Though researchers have no historical records of the eruption's aftermath in Iceland, the impact was likely significant.
"The effects of the Eldgjá eruption must have been devastating for the young colony on Iceland -- very likely, land was abandoned and famine severe," said Andy Orchard, an English professor at the University of Oxford.
The memory of the Eldgjá lived on in the island's culture and poetic lore, however, and only a few decades later, the Voluspá poem, which can be dated to as far back as 961 AD, credits the Eldgjá fallout with paving the way for Iceland's conversion to Christianity.
"The sun starts to turn black, land sinks into sea; the bright stars scatter from the sky," the poem reads. "Steam spurts up with what nourishes life, flame flies high against heaven itself."
The portentous conditions marked the end of Iceland's belief in pagan gods and the arrival of a new, singular god.
"The poem's interpretation as a prophecy of the end of the pagan gods and their replacement by the one, singular god, suggests that memories of this terrible volcanic eruption were purposefully provoked to stimulate the Christianization of Iceland," Oppenheimer said.