Nearly 13,000 years ago a comet impact may have sparked major change in climate

New research suggests that our climate some nearly 13,000 years ago might have been severely changed due to a cosmic intervention. A global team of researchers haspresented its case in four peer-reviewed papers to study the substantially disputed Younger Dryas (YD) impact hypothesis.

According to the studies, it was a comet that led to the plantation of the first seeds of agriculture in Syria, a necessary adaptation to improve the chances of survival.

It was also after the fragments of this comet slammed into Earth’s atmosphere that the climate drastically changed since the plants and animals they relied on disappeared.

Add WION as a Preferred Source

What is YD?

Younger Dryas was a cooling period between roughly 12,900 and 11,600 years ago which disrupted the Earth’s warming trend in the Northern Hemisphere. This period was marked by a rather sudden, severe, and lengthy interruption to the Earth’s climate.

What did the team find?

The team’s research is based on their analysis of the sediment layers from the Neolithic site Abu Hureyra, which was excavated in the 1970s before being submerged under Lake Assad. Notably, Abu Hureyra is said to be the earliest evidence of a shift from hunter-gathering to farming phase.

“We present substantial new quantitative evidence and interpretations supporting the hypothesis that comet fragments triggered near-global shifts in climate ~12,800 years ago, and one airburst destroyed the Abu Hureyra village,” the researchers wrote.

According to the researchers, sediment layers revealed a number of factors which included types of plants before and after the YD climate change. The data also included “changes in building architecture, diet, the early stages of persistent cultivation of domestic-type grains and legumes,” said the authors.

The also shows the “initial penning of livestock, marking the beginning of sustained agriculture and animal domestication.” The team also found shock-fractured quartz grains that were not only consistent with the impact but also evidence of a massive firestorm.

“Shocked quartz is well known and is probably the most robust proxy for a cosmic impact,” Earth scientist James Kennett of the University of California Santa Barbara said in a statement.

“For the first time, we propose that shock metamorphism in quartz grains exposed to an atomic detonation is essentially the same as during a low-altitude, lower-pressure cosmic airburst,” he added.

The second study identified the shock-fractured quartz at the site’s sediment layer from the beginning of the YD period. Some quartz grains in this layer were similar to those found in nuclear explosions and Meteor Crater.

Most of these shock-fractured quartz had been exposed to temperatures of at least 1713 degrees Celsius or higher, said the study.

The third study found small diamonds, special crystals, and small balls made of silica and iron in the sediment layer from the beginning of the YD period some of which could have only been formed under higher temperature or pressure conditions that no human had the ability to produce at the time.

The researchers in the final study present evidence that historically there is a direct connection between cosmic impacts, environmental shifts and changes in societies. Therefore, the team proposes that this major shift came due to the disintegration of a 100-kilometre-wide comet.

WATCH WION LIVE HERE

You can now write for wionews.com and be a part of the community. Share your stories and opinions with us here.