What does the Anthropocene epoch mean?

The Anthropocene (pronounced an-thruh-puh-seen) epoch refers to an unofficial unit of geological time that describes the most recent chapter in our planet’s history. During this time, human activity has had a significant impact on the planet’s climate and ecosystems, via increased fossil fuel consumption, nuclear weapons tests and deforestation. The proposal to formally adopt the Anthropocene as a new epoch must pass the Subcommission on Quaternary Stratigraphy, which is responsible for subdividing Earth’s history from the past 2.4 million years. The proposal must then pass a vote at the larger International Commission on Stratigraphy before being ratified at the International Geological Congress in South Korea next year. Some geologists have expressed concern about adopting a new chapter in Earth’s history, describing the Anthropocene as an event, rather than a formal epoch. Until the new terminology is endorsed, we are still in the Holocene epoch, which began nearly 12,000 years ago.

When did the Anthropocene begin?

The Anthropocene Working Group says it began in the middle of the 20th century. Since then, humanity has tested nuclear weapons, spewed radioactive material into the atmosphere and significantly increased consumption of fossil fuels, contributing to global warming.

Where is Crawford Lake and how deep is it?

Crawford Lake is in Milton, Ontario, a Toronto suburb that is home to more than 124,000 people . The lake is close to 80 feet deep, according to the Anthropocene Working Group , and the sediments at its bottom form annual layers that record human interactions with the environment over the past thousand years. Crawford Lake was among a dozen “golden spike” candidate sites that show evidence of the same simultaneous surge in human pollution around 1950, The Post reported . A “ golden spike ” refers to a spot in the geologic record where proof of a global transformation is perfectly preserved. This week, the Anthropocene Working Group’s 22 voting members announced that Crawford Lake best shows the geological shift that has taken place as a result of human activities. The lake holds evidence of nuclear fallout, industrial pollution, species extinctions and global warming .

What is the Anthropocene Working Group?

Established in 2009 by the Subcommission on Quaternary Stratigraphy, the Anthropocene Working Group is a gathering of scientists who have worked to determine whether the mid-20th century marks the beginning of a new phase of geologic history. It is chaired by Colin Waters, a geologist at the University of Leicester, and its members have included academics in Australia, Canada, China, Japan, Poland, Switzerland, Britain and the United States. They hail from diverse disciplines including archaeology, chemistry and geology.

So what does this all mean?

It has long been established that human activity has inflicted major changes to the planet, such as rapid global warming and the loss of species. This debate about whether to adopt the Anthropocene as a new epoch is focused on whether humans have caused enough environmental damage to alter the basic functions of the Earth system and leave a lasting mark in the geologic record.

Earth may be starting a new geological chapter. What is the Anthropocene?

By Andrew Jeong

and

Sarah Kaplan

July 12, 2023 at 2:15 p.m. EDT

Scientists conduct core sampling at Crawford Lake on April 12 in Milton, Ontario. The layers of sediment from the lake hold centuries of data — including regarding the human influence on the environment. (Bonnie Jo Mount/The Washington Post)

4 min

A lake in Canada serves as the best proof that humans have caused lasting and significant environmental changes to the planet since the mid-20th century — so much so that a group of scientists says a new formal chapter, called the Anthropocene, should be added to the planet’s official history.

Want to know how your actions can help make a difference for our planet? Sign up for the Climate Coach newsletter, in your inbox every Tuesday and Thursday.

The body of water, Crawford Lake, has layered sediments that record more than a thousand years of environmental history, including proof of humanity’s adverse impacts on the planet since the mid-20th century, The Washington Post has reported. Many of the changes “will persist for millennia or longer, and are altering the trajectory of the Earth,” according to the Anthropocene Working Group.

If the findings are endorsed by the wider geological community, Earth will have a new interval added to its 4.6 billion-year timeline. It will also bolster awareness of how human-driven pollution — including planet-warming gases from burning fossil fuels — has transformed the planet in fundamental and dangerous ways.

Here’s what to know about the Anthropocene epoch, and why it matters.