The Anthropocene became part of the zeitgeist after Nobel laureate Paul Crutzen launched the idea in 2000. This is the notion that a crescendo of human impacts has recently propelled the Earth out of the relatively stable climatic conditions of the Holocene epoch, during which human civilisation developed and flourished, to produce a new kind of planet. Then, the idea seemingly crashed to earth in 2024 when the International Commission on Stratigraphy rejected its incorporation into the official geological timescale. So where are we now? Has our planet not changed? Is the Anthropocene idea dead? One can be forgiven for being confused.But the Anthropocene was never only a question of what to call a chunk of geological time. The planet we live on is becoming hotter, more polluted, biologically degraded and its surface and underground increasingly reshaped by human activities. Once the stuff of sci-fi, these symptoms are now real and won’t disappear – they’re ever more a matter of life and death for millions of people. We and our co-authors have just published two articles in the journal Nature Reviews Earth & Environment that explore these questions from different angles. One details the evidence presented in our 2023 proposal to make the Anthropocene a new formal epoch: evidence then scrutinised in closed session by the geological bodies sitting in judgment, but only now published in peer-reviewed form. Over a hundred lines of evidence, from 12 exhaustively studied locations around the world, show that, geologically, the Anthropocene is rock solid. The Earth really did change, as an interconnected system, in the mid-20th century; and a level dated to 1952, when the first thermonuclear blast spread plutonium particles worldwide, marks an effective geological boundary for this new time interval. The evidence presented was not disputed. The official rejection was instead over whether a geological epoch – usually measured in millions of years (though the Holocene epoch is less than 12 millennia) – should be declared after just seven decades.The idea is still spreadingOur second study looks beyond this question of formal geological status, charting the Anthropocene as an idea that is still spreading and making waves. In recent years, dedicated institutes and networks have sprung up in Stockholm, Jena, Vienna, Daejeon and Beijing. And their strength lies in bringing different disciplines together, where the social sciences and humanities are as – or more – important than the Earth sciences.There’s good reason for this. The science of the Anthropocene is multi-faceted and sophisticated. Yet the patterns that emerge are often astonishingly simple: human activity accelerated in all sorts of ways at roughly the same time. The iconic hockey-stick-shaped graph of rising global temperature has many counterparts, whether charting the rise of plastics and aluminium production, the consumption of supermarket chickens, or the use of telecommunications. A selection of many graphs published in the original ‘great acceleration’ study in 2015. Stockholm Resilience Centre / Will Steffen et al 'The trajectory of the Anthropocene: The Great Acceleration (2015)', CC BY-SA These are all aspects of the so-called “great acceleration”: the rapid growth, since the mid-20th-century, of population, industrialisation and globalisation that transformed humanity’s impact on the Earth. This simple pattern of steep growth pervades the Anthropocene – but its human causes and consequences are much harder to pin down. Myriad interlocking forces are at work here, analysed by such disciplines as history, economics, law, education and politics, and explored by literature and the arts.It’s not simply academic analysis. We need to influence this planetary transformation, avoiding the worst-case scenario of a hothouse Earth, and mitigating changes that are unavoidable. Take the international law of the sea, that underpins the regulation of national boundaries and of rights over maritime spaces. For four centuries, this assumed a context of changing human politics and nations, but a stable configuration of land and sea “since time immemorial”.In the Anthropocene, this stability no longer holds: melting sea ice, rising seas and eroding coasts are altering the geography on which some of those rules were based. Legal scholars are having to devise new ways of adapting international law, aimed at upholding rights and keeping the peace on a fast-evolving planet. To prepare us all for the challenges ahead, educationalists are designing curricula that can allow students, present and future, to cope with a world where many old certainties no longer hold.Seeing the planet as a wholeBut is the Anthropocene needed? After all, its individual features, such as climate transformation, sea-level rise, global freshwater use, biodiversity loss and homogenisation, concrete production, and technological hyper-evolution, are actively being studied. The problem is that these issues are not separate (even if they’re often treated as such in our still-siloed knowledge framework). They’re all tightly interconnected and all part of a single Earth system that is transforming as a whole. Hence, our analysis – and our political responses – need to be systemic, and not ad hoc, simply firefighting each symptom as it flares up. No other concept reflects this planet-wide transformation in its proper context of deep time.Does the Anthropocene need to be formal? Well, this would help greatly. The Anthropocene has gathered many interpretations since it was first proposed, some very different from its original, essential meaning of a marked departure from Holocene stability. Formal stabilisation would help us all talk about the same thing: a useful quality, when it refers to the planet we all share.The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.