Experts have said the indelible imprint left by human beings on Earth has become so clear that it justifies naming a new geological epoch after mankind.
The dawn of the “Anthropocene” would signal the end of the Holocene epoch, considered to have begun 11,700 years ago at the end of the Ice Age.
“Human activity is leaving a pervasive and persistent signature on Earth,” said a report in the journal Science by an international team led by Dr Colin Waters of the British Geological Survey.
“We are becoming a geological agent in ourselves,” Dr Waters told Reuters.
The start date could be around the mid-20th century, the authors wrote.
They said the atomic age, starting with a bomb test in New Mexico in the United States on July 16, 1945, and the post-war leap in mining, industry, farming and use of manmade materials such as concrete or plastics all left geological traces.
Concrete, invented by the Romans, was now so ubiquitous that it would amount to one kilogram for every square metre of the planet’s surface if spread out evenly, they said.
Reuters reports some experts reckon the Anthropocene began with Europe’s Industrial Revolution in the 18th century.
Others would give it a more widespread origin, dating it from the spread of agriculture several thousand years ago.
“Any definition will inform the stories that we tell about human development,” said Professor Simon Lewis of University College London, who was not involved in the study.
Professor Erle Ellis of the University of Maryland, a co-author of the study, said pinning down the Anthropocene would transform understanding of humanity’s role on the planet.
He said it was a “challenge no smaller than a second Copernican revolution”. In the 16th century, Nicolaus Copernicus helped show the Earth rotates around the sun.
Abstract of the study available here