What is the Anthropocene and when did the Earth enter this new era
Environment — di Andrea Barolini
According to leading experts gathered in South Africa, human activity has propelled the Earth into a new geological era: the Anthropocene.
What is the Anthropocene and when did the Earth enter this new era
According to leading experts gathered in South Africa, human activity has propelled the Earth into a new geological era: the Anthropocene.
Human activities have by now modified our planet so profoundly as to have very likely propelled it into a new geological era: the Anthropocene. This was confirmed by a group of scientists gathered on 29 August in Cape Town, South Africa, on the occasion of the most recent International Geological Congress.
As reported by the British newspaper The Guardian, of the 35 experts present, 30 approved the transition to the new phase of Earth's life (three votes against and two abstentions). It will now fall to the International Union of Geological Sciences (Iugs) to give definitive confirmation of the change, and of the consequent departure from the current era, known as the Holocene, which began approximately ten thousand years ago.
What does Anthropocene mean?
The word Anthropocene was coined by the Dutch chemist and Nobel laureate Paul Crutzen. It literally denotes "the age of man", that is, a phase characterised by the human footprint on the global ecosystem. Taking into account climate change, soil erosion, ocean warming and the extinction of numerous species, the "weight" of anthropogenic activities seems evident. For geologists, however, it is necessary to detect a tangible "signal" of such activities in the Earth's rocks.
For instance, as a France Info analysis recalls, the era of the dinosaurs' disappearance coincided with the presence of an unusual concentration of iridium in the rocks: a chemical element that is relatively rare on Earth but common in meteorites. The hypothesis of a celestial body crashing into the Earth is indeed among the most widely accepted explanations for the dramatic reduction in living species that occurred approximately 66 million years ago, which brought about the end of the so-called Cretaceous period (considered the last of the Mesozoic era).
Radioactivity could constitute the "proof"
To this end, the Iugs will now have three years to carry out analyses on lake sediments, ice cores from Antarctica, and coral samples in order to obtain "proof" of the transition to the Anthropocene.
According to Jan Zalasiewicz, an expert consulted by the British newspaper, this will not be difficult: plastic, aluminium and cement particles can readily be considered an unambiguous signal of human impact on the Earth. Above all, however, as the newspaper Le Monde underlines, it could be the radioactivity dispersed as a result of nuclear tests and accidents that represents the most tangible trace of the entry into the new geological era.