Geologists spent 15 years debating the Anthropocene, then voted it down
You may have heard that we now live in the Anthropocene, a new geological age shaped by humans. Officially we do not. In 2024, after roughly 15 years of argument and a chosen Canadian lake full of bomb-test plutonium, the bodies that keep the geological time scale rejected it as an epoch.
The idea is old. The Italian geologist Antonio Stoppani wrote of an anthropozoic era in 1873, and Vladimir Vernadsky described scientific thought as a geological force in 1938. The ecologist Eugene Stoermer used the word Anthropocene in the 1980s, and the atmospheric chemist Paul Crutzen made it famous in 2000, arguing that human effects on the air amounted to a new epoch after the Holocene.
The hardest question was when it would start. Candidates ranged from the dawn of farming, some 12,000 years ago, to the Industrial Revolution around 1780. James Lovelock suggested 1712, the first use of Newcomen's steam engine. Early in 2015 a paper signed by 26 of the working group's 38 members backed the Trinity nuclear test of 16 July 1945, while another report that year floated 1610 or 1964.
The working group eventually settled on the mid-20th century, when population, industry, fertiliser use and fossil-fuel burning surged and atomic tests scattered radioactive debris into sediments and ice. In May 2019, 29 of its 34 members backed a formal proposal. Twelve sites were weighed before Crawford Lake in Ontario was picked in 2023; its layered mud shows a plutonium spike from hydrogen bomb tests, plus carbon particles and nitrates, with the start set at 1950.
It failed anyway. In March 2024 the Subcommission on Quaternary Stratigraphy rejected it 12 to 4 with two abstentions, and the International Commission on Stratigraphy and IUGS confirmed the decision almost unanimously. Voters were not denying human impact; they found the sedimentary record too thin, the start date too recent, and the choice of 1950 blind to far older changes. Critics had also argued the Anthropocene is better seen as a drawn-out event than a single dated boundary. The word remains in wide informal use.
Source: Anthropocene
