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26 April 2017

Did a Comet Impact Trigger the Younger-Dryas Cold Event?

The Younger Dryas, named after the cold-favouring flower Dryas octopetala, was a period of abrupt change for the Earth’s climate. Following a steady warming of the Northern Hemisphere which saw glaciers begin to retreat in favour of a more hospitable climate, the process suddenly reversed around 13,000 years ago. Temperatures plummeted, and the Northern Hemisphere returned to a near-glacial state. This period of intense cold lasted for over 1,000 years.

The exact cause of this sudden shift in the climate of the Northern Hemisphere has long been debated, and there remains no concrete or universally-accepted answer. However, the authors of a new study recently published in the journal Mediterranean Archaeology and Archaeometry believe they may have found the answer in ancient carvings found at Gobekli Tepe, an archaeological site in Southern Turkey.

The Vulture Stone (partially obscured) in place at Gobekli Tepe in southern Turkey   - Img: Alistair Coombs
The carvings, specifically those found on a pillar at the site known as the Vulture Stone, suggest that a swarm of comet fragments have may hit the Earth sometime around 11000 BC, triggering the event now known as the Younger Dryas.

One image in particular, that of a headless man, is thought to represent a disastrous and extensive loss of human life. A number of other symbols are believed to be evidence that the people of Gobekli Tepe recorded changes to the Earth’s rotational axis during the time period in question.

The fact that the site appears to have remained important to the local peoples for an extended period of time further indicates that the event to which the carving refers was an important one with lasting ramifications.

In order to properly date the event, researchers used computer software to match carvings of animals, interpreted as astronomical symbols, to constellations of stars. This allowed them to pinpoint the event to 10950 BC, as reported by New Scientist. This is backed up by evidence taken from ice cores in Greenland, which suggests the same time frame for the Younger Dryas.

“It appears Gobekli Tepe was, among other things, an observatory for monitoring the night sky,” says lead researcher Martin Sweatman, from the University of Edinburgh’s School of Engineering.

“One of its pillars seems to have served as a memorial to this devastating event – probably the worst day in history since the end of the Ice Age.”

Sweatman does state that his study is far from providing ultimate proof of this hypothesis, but he certainly makes a compelling argument.

Sam Bonson

Sam is an aspiring novelist with a passion for fantasy and crime thrillers. He is currently working as a content writer, journalist & editor in an attempt to expand his horizons.