There's no question about it. A new epoch—the Anthropocene—has begun.
So says an international group of geoscientists, in a paper published Friday in the journal Science. They point to waste disposal, fossil fuel combustion, increased fertilizer use, the testing and dropping of nuclear weapons, deforestation, and more as evidence that human activity has pushed the Earth into the new age that takes its name from the Greek anthropos, or human being.
Some argue the new era began in the 1950s, the decade that marks the beginning of the so-called "Great Acceleration," when human population and its consumption patterns suddenly speeded up, and nuclear weapons tests dispersed radioactive elements across the globe.
Formalizing the Anthropocene era—a designation that must come officially from a separate body known as the International Commission on Stratigraphy—they write, "expresses the extent to which humanity is driving rapid and widespread changes to the Earth system that will variously persist and potentially intensify into the future." The scientists are likely to present their findings to the Commission later this year.
"What this paper does is to say the changes are as big as those that happened at the end of the last ice age," Colin Waters, principal geologist at the British Geological Survey and an author of the study, told the Guardian. "This is a big deal."
As Smithsonian magazine notes, "The new study is not the first to propose a formal establishment of an Anthropocene epoch—Simon Lewis and Mark Maslin of the University of College London made a similar recommendation last year—but it is one of the most comprehensive to date."
Among the tell-tale signs that the Anthropocene has started, according to reporting on the study:
- Über-industrialization. "More than half the earth's surface has been transformed into settlements and cities, agricultural land, mines, waste dumps, baseball diamonds, and beyond," writes journalist Eric Roston at Bloomberg. What's more, he adds, "Mineral mining moves three times more sediment every year than all the world's rivers."
- Plastics everywhere. "Even most mud samples taken from remote ocean beds now contain plastic fragments," academics and write for The Conversation. "Buried in sediment, these materials may be preserved over geological timescales, forming new rocks and rapidly-evolving 'technofossils' for our descendants to marvel at."
- Biologic changes. "We've pushed extinction rates of flora and fauna far above the long-term average," the Guardian reports. "The Earth is now on course for a sixth mass extinction which would see 75% of species extinct in the next few centuries if current trends continue."
- Nuclear fallout. "Our war efforts have left their mark on geology," notes New Scientist. "When the first nuclear weapon was detonated on 16 July 1945 in New Mexico, it deposited radionuclides—atoms with excess nuclear energy—across a wide area. Since 1952, more explosive thermonuclear weapons have been tested, leaving a global signature of isotopes such as carbon-14 and plutonium-239."
- Greenhouse gas levels. As Common Dreams has reported extensively, and the geoscientists point out, atmospheric concentrations of greenhouse gases like carbon dioxide and methane are higher than they've ever been. "Depending on the trajectory of future anthropogenic forcing, these trends may reach or exceed the envelope of Quaternary interglacial conditions," the study authors write—in other words, conditions could become more extreme than in previous ice ages.
Still, as damning as this evidence is, observers have cautioned against a simplistic view of geologic shifts. "Anthropocene is...suspect because—to the extent that 'we' wish to name the new epoch after a force, it generically identifies that force as humanity as a whole, rather than the identifiable power structures most responsible for the geological Anthropocene traces," wrote Kieran Suckling, founding director of the Center for Biological Diversity, in 2015.
Indeed, Ian Angus, editor of the ecosocialist journal Climate and Capitalism, argued last year: "An ecosocialist analysis of the Great Acceleration will build on the decisive issues of class and power that are shaping the Anthropocene and will ultimately determine humanity’s future."