Scientists say humans have now brought on an entirely new geologic epoch

[Tab]

A group of 24 geoscientists on Thursday released a bracing assessment, suggesting that humans have altered the Earth so extensively that the consequences will be detectable in current and future geological records. They therefore suggest that we should consider the Earth to have moved into a new geologic epoch, the “Anthropocene,” sometime circa 1945-1964.

The current era (at least under present definitions), known as the Holocene, began about 11,700 years ago, and was marked by warming and large sea level rise coming out of a major cool period, the Younger Dryas. However, the researchers suggest, changes ranging from growing levels of carbon dioxide in the atmosphere to infusions of plastics into marine sediments suggest that we’ve now left the Holocene decisively behind — and that the proof is already being laid down in polar ice cores, deep ocean sediments, and future rocks themselves.

“In a way it’s a thought experiment,” said Naomi Oreskes, a geologically trained Harvard historian of science and one of the study’s authors. “We’re imagining what a future geologist will see when he or she looks at the rock record. But it’s not that difficult a thought experiment to do, because so many of these signals are already present.”

The paper was published Thursday in the journal Science and was led by Colin Waters, a geologist with the British Geological Survey.

“Quite unlike other subdivisions of geological time, the implication of formalizing the Anthropocene reach well beyond the geological community,” the authors conclude. “Not only would this represent the first instance of a new epoch having been witnessed firsthand by advanced human societies, it would be one stemming from the consequences of their own doing.”

[Gregorian]

1. Here's a link

I was rather interested in the infusions of plastics into marine sediments part. I had not heard of that.

https://www.washingtonpost.com/news/energy-environment/wp/2016/01/07/scientists-say-humans-have-now-brought-on-an-entirely-new-geologic-epoch/

Actually, here's the original paper:

http://www.sciencemag.org/content/351/6269/aad2622

[Tab]

2. Oops - forgot the link - thanks!

[Jim Lane]

3. This is a new paper but hardly a new proposal

The term has been under discussion for quite a while. Here's the first paragraph of the Wikipedia article on "Anthropocene":

The Anthropocene is a proposed epoch that begins when human activities started to have a significant global impact on Earth's ecosystems.[1][2] The term – which appears to have been used by Soviet scientists as early as the 1960s[3] to refer to the Quaternary, the most recent geological period – was coined with a different sense in the 1980s[4] by ecologist Eugene F. Stoermer and has been widely popularized by atmospheric chemist Paul Crutzen, who regards the influence of human behavior on the Earth's atmosphere in recent centuries as so significant as to constitute a new geological epoch for its lithosphere. As of January 2016, the term has not been adopted formally as part of the official nomenclature of the geological field of study.

The article goes on to give more information about the status of the concept within the scientific community. Of particular note is that a process is underway that could result in its formal adoption as part of the geologic time scale.