The ‘new age of man’: Scientists are a step closer to declaring the dawn of the Anthropocene era – marking the beginning of humanity’s irreversible impact on Earth
- Scientists are a step closer to officially declaring a new geological time segment
- Antropocene marks the beginning of humanity’s irreversible impact on Earth
Scientists are a step closer to officially declaring a new geological time segment that marks the beginning of humanity’s irreversible impact on Earth.
An international team of experts have put forward Crawford Lake in Ontario as the official ‘ground zero’ of the Anthropocene epoch.
The Anthropocene describes the time in Earth’s history when human activities began to have a significant influence on the global systems.
The scientists said the formal start date of this epoch is the 1950s, coinciding with the appearance of plutonium, a man-made radioactive element used in nuclear weapons, as well as the start of ‘the great acceleration’, which refers to the dramatic surge of human activity across the planet.
Professor Andrew Cundy, chair in environmental radiochemistry at the University of Southampton, said: ‘Recognition of the Anthropocene as a geological epoch I think is important, because it really evidences to wider society the true extent of our impacts on the Earth.’
Scientists are a step closer to officially declaring a new geological time segment that marks the beginning of humanity’s irreversible impact on Earth
An international team of experts have put forward Crawford Lake in Ontario as the official ‘ground zero’ of the Anthropocene epoch
What is the Anthropocene era?
The Anthropocene is the name of a proposed geological epoch that may soon enter the official Geologic Time Scale.
It refers to a time in which human permanently changed the planet.
According to the International Union of Geological Sciences (IUGS), we are officially in the Holocene epoch, which began 11,700 years ago after the last major ice age.
Some experts argue we should now change the name to ‘Anthropocene’. This is from from anthropo, for ‘man,’ and cene, for ‘new’.
But up until now, experts have been divided on when mankind caused a lasting impact on the Earth’s geology with some suggesting 1964 when the fallout from atomic testing became apparent.
The Crawford Lake was among 12 other sites: including a peat bog in Poland; an ice sheet in Antarctica; and a coral reef in Australia; that were investigated by the Anthropocene Working Group (AWG).
Professor Francine McCarthy, a micropaleontologist at Brock University in Canada and an AWG member, said that Crawford Lake was chosen because it is ‘completely isolated from the rest of the planet except for what gently sinks to the bottom and accumulates as sediment’.
For a thousand years, this lake has been absorbing the signs of changes from the world above, which is now permanently preserved in layers of mud.
Digging into these layers, scientists found markers of the profound changes caused by humans to the planet’s climate and chemistry.
Geologists said these markers are the ‘golden spike’ – or, more formally, the Global Boundary Stratotype Section and Point (GSSP) – heralding the start of the Anthropocene.
Dr Simon Turner, from University College London, who is also the AWG secretary, said: ‘The sediments found at the bottom of Crawford Lake provide an exquisite record of recent environmental change over the last millennia.
‘It is this ability to precisely record and store this information as a geological archive that can be matched to historical global environmental changes which make sites such as Crawford Lake so important.’
Samples from the lake and other sites have also revealed traces of plutonium, a result of nuclear bombs being tested in the atmosphere.
Crawford Lake was chosen because it is ‘completely isolated from the rest of the planet except for what gently sinks to the bottom and accumulates as sediment’
Samples from the lake and other sites have revealed traces of plutonium, a result of nuclear bombs being tested in the atmosphere
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Professor Cundy said: ‘The presence of plutonium gives us a stark indicator of when humanity became such a dominant force that it could leave a unique global fingerprint on our planet.
‘In nature, plutonium is only present in trace amounts.
‘But in the early 1950s, when the first hydrogen bomb tests took place, we see an unprecedented increase and then spike in the levels of plutonium in core samples from around the world.
‘We then see a decline in plutonium from the mid 1960s onwards when the Nuclear Test-Ban Treaty came into effect.’
Other indicators of human activity found in sediments include microplastics, ash from coal-fired power stations, concrete, and high concentrations of heavy metals such as lead.
Some have suggested the Anthropocene should begin at the start of Britain’s Industrial Revolution in the 18th century, which created the world’s first fossil fuel economy.
But Colin Waters, honorary professor at University of Leicester and chair of the AWG, said that while there is evidence of the Industrial Revolution’s impact in the UK and Europe, countries in Asia and other parts of the southern hemisphere were largely unaffected by it during that time.
He added: ‘So the more we looked into this, and it was not until probably about 2014, that we actually came to this conclusion that, really, the point across the planet where you start to see a synchronous change is the middle of the 20th century.’
Officially, humanity and all the other inhabitants of Earth are still living in the Holocene epoch, which began about 11,700 years ago when the climate became more stable.
The Anthropocene has been debated by experts since the phrase was coined by atmospheric chemist Paul Crutzen more than two decades ago but is yet to be formally recognised as a unit of geologic time.
However, Professor Waters believes it is unlikely the planet will ever return to its Holocene state, due to irreversible human-induced changes which ‘has caused greenhouse gas emissions into the atmosphere, which will take thousands of years to return back to what might be considered to a Holocene level’.
Professor McCarthy added: ‘I can think of one other species that has affected the planet more (than humans) and those are the cyanobacteria who, (about) two billion years ago, oxygenated the atmosphere.’
Researchers claim the Earth is going through a ‘man made’ sixth mass extinction with the ‘biological annihilation’ of wildlife
The world has experienced five mass extinctions over the course of its history, and experts claim we are seeing another one happen right now.
A 2017 research paper claimed a ‘biological annihilation’ of wildlife in recent decades has triggered the sixth mass extinction and says the planet is heading towards a ‘global crisis’.
Scientists warn humanity’s voracious consumption and wanton destruction is to blame for the event, which is the first major extinction since the dinosaurs.
Two species of vertebrate, animals with a backbone, have gone extinct every year, on average, for the past century.
Currently around 41 per cent of amphibian species and more than a quarter of mammals are threatened with extinction.
There are an estimated 8.7 million plant and animal species on our planet and about 86 per cent of land species and 91 per cent of sea species remain undiscovered.
Of the ones we do know, 1,204 mammal, 1,469 bird, 1,215 reptile, 2,100 amphibian, and 2,386 fish species are considered threatened.
Also threatened are 1,414 insect, 2,187 mollusc, 732 crustacean, 237 coral, 12,505 plant, 33 mushroom, and six brown algae species.
More than 25,000 species of 91,523 assessed for the 2017 ‘Red List’ update were classified as ‘threatened’.
The number of invertebrates at risk has also peaked.
Scientists predict insects may go extinct within 100 years as a result of crippling population decline.
The dawn of the mass extinction coincides with the onset of the Anthropocene – the geological age defined by human activity being the dominant influence on climate and the environment.
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