Not Yet Anthropocene: What the Official Rejection of Earth’s New Epoch Means for the Climate Discourse

After 15 years of charged academic debate, the International Union of Geological Sciences (IUGS) earlier this year announced its rejection of the official proposal to formalize the Anthropocene as Earth’s new geological epoch. With global average temperatures soaring and the consequences of a rapidly changing climate becoming increasingly widespread and severe, what does the decision mean for scientific and popular discourses around anthropogenic climate change? 

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It is inarguable that humans have had an age-defining impact on planet Earth. Over two decades ago, this thought led scientists Paul Crutzen and Eugene Stoermer to first formulate the idea of the Anthropocene, a term asserting that human (or anthropogenic) influences on our planetary ecosystems have now become so dominant and so destabilising to necessitate the establishment of a new chronostratigraphic epoch in the official geological timeline of Earth.

In recent decades, the Anthropocene has gained immense scientific and popular currency within the global discourse on anthropogenic climate change, finding particular evocation in moral-political pleas for urgent action to temper the ever-increasing reality of the destructive impact of human actions. Despite the term’s global ubiquity, however, its scientific usage has remained informal: confirmation that the Anthropocene is officially Earth’s new geological reality has rested on the outcome of one and a half decades of tense academic debate over the scientific validity of the term. 

In March 2024, this debate came to an end, as the International Union of Geological Sciences (IUGS), the governing body of the geological discipline, voted to officially reject the Anthropocene proposal. In view of the seemingly undeniable reality of our destructive human impact, what does the rejection of the term mean for the discourse around anthropogenic climate change?

More about the topic: Explainer: What Is the Anthropocene?

A Long-Awaited Decision

Following the popularity surrounding the term, the Anthropocene Working Group (AWG) was formally established in 2009 by the Subcommittee on Quaternary Stratigraphy (SQS), a sub-group within the IUGS, to develop an official proposal that outlined sufficient geological evidence to support the existence of a distinct Anthropocene epoch. In geology, the formalisation of a new chronostratigraphic unit in the official Geological Time Scale calls for a “golden spike” – material evidence in the stratigraphic (rock strata) record from one physical location on Earth, demonstrating a discrete change in Earth’s geological history. The proposed golden spike must be approved by the International Commission on Stratigraphy (ICS), under the IUGS. 

Research on the Anthropocene start date has generated dozens of theses regarding when the era began and which location is the most definitive golden spike, but the official AWG proposal ultimately landed in 1952. This date represents the start of the so-called Great Acceleration in mass-scale human production and consumption, based on an influx of recent evidence that has found radioactive residue, microplastics, pesticides, and ash from fossil fuel combustion across the global geological record. The final AWG proposal selected the specific evidence of the radioactive plutonium deposits from 20th-century hydrogen bomb tests found in the sediment of Crawford Lake in Ontario, Canada, as the golden spike. 

Although scientific evidence demonstrating the dominance of human influences on Earth’s geology is extensive, the SQS vote resulted in a conclusive “no” to the Anthropocene, with 12 out of the 16 members voting against the proposal. Despite a firm challenge from SQS chairman Jan Zalasiewicz and vice-chair Martin Head regarding alleged “procedural irregularities” surrounding the vote, the IUGS officially terminated the challenge on March 20, endorsing the original vote with 15 out of 17 in favour. 

The controversy surrounding the final vote is emblematic of the broader academic debate over the Anthropocene, with the last 15 years witnessing heated academic exchanges and three resignations from the AWG due to disputes over the term. With such contention over the new geological epoch, the recent rejection clearly holds significant and varying implications for how we, as humans, understand our place in our present global reality, and for how we use the term in the discourse around climate change.

The Rejection and Its Implications 

Does the rejection actually mean that we aren’t in the Anthropocene? That anthropogenic climate change is less-real of a global reality? The foremost answer is no. 

It is impossible to deny the monumental, destructive impacts that human activities have had on the planet, and the rejection of the term is not meant to contradict this reality; scientific evidence showing the significance of anthropogenic influences on the environment from leading global scientific organisations such as the Intergovernmental Panel on Climate Change (IPCC) and IUGS has been met with near-unanimous approval. The IUGS has not ignored scientific evidence, as some have alleged, or intended to deny the destructive reality of global climate change. What the debate and rejection show, rather, is that the Anthropocene is fundamentally political: the term has transcended scientific semantics to become a political battleground in the all-encompassing struggle to understand our global environmental reality, our role as humans within it, and why we now need to act sustainably, to reverse the harm we have inflicted.

“The proliferation of this concept can mainly be traced back to the fact that, under the guise of scientific neutrality, it conveys a message of almost unparalleled moral-political urgency,” wrote German cultural theorist Peter Sloterdijk.

For some, then, the scientific rejection of the Anthropocene has only borne negative consequences for the political discourse on anthropogenic climate change. Without an accepted, stable scientific definition, some contend that the term now lacks the discursive utility to unite global understanding of the problem and catalyse global solutions, an implication that is particularly worrying in consideration of the existing urgency for international climate action.

“The IUGS ruling means that the Anthropocene will confusingly continue to represent widely different concepts. This has been a missed opportunity to recognise and endorse a clear and simple reality, that our planet left its natural functioning state, sharply and irrevocably, in the mid-20th century,” said Zalasiewicz.

A considerable group of observers, however, have instead viewed the rejection as an opportunity. Over the course of the wider debate, many of the scientific objections to the Anthropocene have centred on the definitional narrowness of the term – stemming from the fact that the IUGS’s criteria for a golden spike required that the AWG specify one fixed start date for the Anthropocene, represented by one set location. It was this reason that spurred ecologist Erle Ellis’s resignation from the AWG last year: “[The AWG] has become so focused on promoting a single narrow definition of the Anthropocene that there is no longer room for dissent or for a broader perspective,” he wrote in his official resignation letter.

For those such as Ellis that have criticised the conceptual strictness of the AWG, the rejection has in fact supplied an opportunity for alternative narratives on the Anthropocene to emerge, with the most favoured suggesting that we define the Anthropocene as an event in geological history rather than an epoch. 

Events in geology, such as the Cambrian Explosion or Great Oxidation Event, are characterised as gradual transformations over time instead of the abrupt material shift that marks an epoch. For Ellis and many others, understanding the Anthropocene as a wider socio-historical process rather than as a discrete break in geological time imbues the term with more meaning, allowing it to serve instead as a broad multidimensional concept that better encompasses the long global history of eras and geographies across which humans have had a dominant impact on the environment – from the Columbian Exchange to the Industrial Revolution to the Great Acceleration, and from the atmosphere to the ocean to the earth. 

Utilising the Anthropocene to tie together a wide array of anthropogenic ecological transformations under the same loose umbrella is, for many, much more useful than a narrow stratigraphical definition that fixes the understanding of our human impact to one point and one place in history. This reasoning composed the core thread that ran through the IUGS’s official rejection, with the governing body rightfully recognising that the Anthropocene “will remain an invaluable descriptor in human-environment interactions” when employed as “an informal non-stratigraphical term.”

“It serves humanity best as a loose concept that we can use to define something that we all widely understand, which is that we live in an era where humans are the dominant force on ecological and geological processes,” said Jacquelyn Gill, a palaeoecologist at the University of Maine.

“There is an impulse to want to put things in capital letters, in formal definitions, just to make them look like they’re nicely organised… What the working group is trying to say is everything pre-1950 is pre-Anthropocene, and that’s just absurd,” remarked Bill Ruddiman, a geologist at the University of Virginia.

Taken further, many argue that the static definition of the Anthropocene does not merely limit understanding of our historical relationship to our environment, but in fact risks actively proliferating a “misleading and regressive” narrative about who and what caused the Anthropocene. “[D]ividing Earth’s human transformation into two parts, pre- and post- 1950, does real damage by denying the deeper history and the ultimate causes of Earth’s unfolding social-environmental crisis. Are the planetary changes wrought by industrial and colonial nations before 1950 not significant enough to transform the planet?”, asked Ellis. 

Ellis’s statement reflects a growing critical perspective that has unpicked the way in which the Anthropocene concept, under the guise of scientific objectivity, in fact promotes a universalising narrative that conceals the particular histories and societies that have engendered our present environmental reality. By reductively describing the Anthropocene as uniform phenomenon caused by a singular, undifferentiated humanity, the term serves as a convenient yet wrongful distortion for the Global North whose scholars coined the concept, concealing the disproportionate responsibility of the Anglo-American societies whose environmentally destructive activities have historically precipitated the present crisis. 

Understanding the Anthropocene as a geohistorical event helps us understand how our present global reality cannot be decoupled from the material histories of Western capitalism and European colonialism, within which lie the origins of our destructive modern practices. It is from this perspective that some have perceptively criticised the composition of the AWG, in which the dominance of Western male geoscientists within the group has been regarded as a procedural failure for an investigation of global reach.

Now Is the Anthropocene

Ultimately, the formal rejection of the Anthropocene term does not mean that anthropogenic climate change is less-real of a global reality. What the verdict does suggest, however, is that we need to adopt a deeper and more nuanced view of this reality – one that embraces the sweeping historical complexity of our human relationship to the environment, rather than one that distorts this history in the attempt to define it through neat scientific labels.

As science journalist Alexandra Witze put it, “By voting ‘no’, [the SQS] actually have made a stronger statement, that it’s more useful to consider a broader view – a deeper view of the Anthropocene.”