Geologists are making it official: We are not in an “Anthropocene” era

Geology’s top governing body has upheld a controversial vote by scientists against adding the Anthropocene, or human epoch, to the official timeline of Earth’s history.

The vote, which a committee of about 20 scientists took in February, ended nearly 15 years of debate over whether we should declare that our species had so thoroughly transformed the natural world since the 1950s that the planet was in a new jacket had been put on. era of geological time.

Shortly after voting ended this month, however, the committee’s chairman, Jan A. Zalasiewicz, and its vice-chairman, Martin J. Head, called for the results to be annulled. They said members voted prematurely before evaluating all the evidence.

Dr. Zalasiewicz and Dr. Head also claimed that many members should not have voted in the first place because they had exceeded their term limits.

After reviewing the matter, the commission’s parent body, the International Union of Geological Sciences, decided that the results should stand, the union’s executive committee said in a statement on Wednesday.

That means it’s official. Our planet, at least for now, is still in the Holocene epoch, which began 11,700 years ago with the most recent melting of the ice caps.

Even if the Anthropocene does not yet have an official place on the geological time scale, the term “will be used not only by earth and environmental scientists, but also by social scientists, politicians and economists, as well as by the general public. large,” the Geological Union statement said. “It will remain an invaluable description of the human impact on the Earth system.”

The statement did not directly address Dr. Zalasiewicz and Dr. Head about the voting process. It only said that the committee members had acted with integrity and had broad expertise as geologists. “The scientific decision is clear, and the specialists see no value in adding a new era to the geological record,” the union’s president, John Ludden, said by email.

Although the voting results have been declared valid, Dr. Head, an earth scientist at Brock University in St. Catharines, Ontario, that he expected the Anthropocene episode would prompt geologists to change their procedures for making decisions about future timescale updates.

“I feel this is a missed opportunity to recognize and acknowledge the simple reality that our planet left its naturally functioning state in the mid-20th century,” said Dr. Head by email. “A large number of geological signals reflect this fact.”

The issue of the Anthropocene has polarized scientists in a way that few issues in the history of the geological time scale have ever experienced.

The scale divides Earth’s past into chapters that summarize planet-wide changes. There is no doubt that our time is full of such changes. Pollution, urbanization, rapid global warming and other disruptions to ecosystems and natural processes have left marks that will remain in the rocks for a long time.

But to merit inclusion on a geological scale, each time interval must meet certain criteria, such as having a clear, objective starting point.

Last month, the first of three scientific committees began voting on whether the decades since World War II fit into the picture. The results, first reported by The New York Times, showed that most committee members were not ready to endorse an era that is still so young, at least by the standards of its 4.6 billion year history from the earth. The rejection means that the Anthropocene issue will not advance to the next voting round.

The results are “a sign that the system is not equipped to deal with the present or the rate of change currently occurring on our planet,” said Brad E. Rosenheim, chairman of the Geological Society’s Geochronology Division of America. a statement.

“While it is unclear whether the Anthropocene will ever become a geological division, it is an important question for all of us to consider: What exactly are we doing with this planet that supports our civilization?” said dr. Rosenheim, a geological oceanographer at the University of South Florida.

With the Anthropocene issue behind us, the keepers of the geological timeline can now turn to other matters. Next on their agenda includes determining when exactly the Late Pleistocene epoch began.

That would be a time, about 130,000 years ago, when the planet was warmer than it is today. As time passed, the world became cold again. The ice caps returned. Neanderthals and other prehistoric ancestors were either wiped out or assimilated, leaving only modern humans.

Geologists say this period deserves an official start date, but they still need to figure out how and where to define it. The question has occupied them for a long time, longer than during the Anthropocene. Much longer even. The first time scientists officially put forward a possible starting point for the late Pleistocene was in 1932.