Scientists Propose 1952 as the Starting Point of the Human-Altered Earth Era

How much have humans changed the Earth? An international research team that includes Endowed Chair Professor Buhm Soon Park of the Korea Advanced Institute of Science and Technology has proposed a common framework for defining the meaning and starting point of the Anthropocene, the period in which human activities have rapidly transformed the global environment. In a perspective article published in the journal Nature Reviews Earth & Environment, the researchers suggest using 1952 as a reference point to separate the relatively stable Earth environment that preceded that year from the rapid, sweeping changes that followed. The proposal is designed to let scientists, policymakers, and educators grasp the scale and speed of today’s environmental crisis with far greater precision than the loose, contested usage that has grown up around the term over the past two decades.

The Anthropocene is a concept used to describe an epoch in which human activities have become powerful enough to affect the Earth’s environment as a whole, from the climate system to ecosystems across every continent. Since the term entered widespread scientific discussion, it has traveled well beyond the natural sciences. It now appears in the humanities and social sciences, in education, and in the arts, where it serves as shorthand for humanity’s planetary footprint. That breadth of adoption, however, has come at a cost. Differing interpretations of what the Anthropocene means, and when it began, have persisted for years, making it difficult for researchers in different fields to compare findings or build on one another’s conclusions. The new paper, part of a special collection titled The Anthropocene debate, seeks to establish a more consistent understanding of the concept and to chart research directions that can be applied across disciplines.

The timing of the proposal is significant. A formal attempt to recognize the Anthropocene as an official geological epoch was not approved in 2024, when the scientific community declined to ratify the designation after years of deliberation. Yet the concept has hardly faded. It continues to be used widely across academic and social fields to describe the impact of human activities on the global environment, and the debate over its formal status has only sharpened interest in what the term should actually signify. Against this background, Park and his international collaborators argue that the most productive path forward is not to keep litigating the question of formal ratification, but to agree on a working definition and a clear reference point that scholars from every discipline can use.

Central to the team’s argument is a caution against defining the Anthropocene too broadly. If the epoch is simply characterized as the period in which humans affected the environment, the researchers point out, it becomes nearly impossible to distinguish the rapid changes of recent decades from the older, slower impacts that humans have always had on their surroundings. Humans have altered landscapes, forests, and waterways for thousands of years, but the authors argue that particular attention should be paid to a qualitative shift: since the mid-twentieth century, the scale of human influence has grown large enough to destabilize the Earth system as a whole. This is not merely a matter of more people doing more things. It is a matter of human activity crossing thresholds that begin to affect the planetary machinery itself, including the carbon cycle, the nitrogen cycle, and the stability of ecosystems on which civilizations depend.

The point of comparison that anchors the framework is the Holocene, the geological epoch that has lasted for approximately 12,000 years. The Holocene began after the last Ice Age ended, and its relatively stable climate and environmental conditions created the stage on which humans developed agriculture, built cities, and constructed civilizations. That stability was not accidental or trivial; it was the environmental foundation of everything from settled farming to global trade networks. The researchers emphasize that identifying the point at which this stability began to be significantly disrupted is essential if scientists want to assess clearly how rapidly and how extensively the Earth’s environment is changing today. Without a defined baseline, claims about unprecedented change remain rhetorical rather than measurable.

Accordingly, the research team proposes 1952 as the starting point of the Anthropocene. The choice coincides with the period known as the Great Acceleration, the mid-twentieth-century surge in which industrialization and urbanization expanded at unprecedented rates and numerous indicators of human activity and the global environment began changing sharply. Graphs of the Great Acceleration, which the team cites as visual evidence for the mid-century starting point, show paired trends: on one side, changes in the socioeconomic system, including population growth, energy use, and economic output; on the other, changes in the Earth system, including atmospheric carbon dioxide concentrations, temperature, and species loss. The synchronization of these curves after 1952 is the empirical heart of the proposal, offering a data-driven rationale for treating that year as the hinge between a stable Holocene world and the human-dominated one that followed.

The practical value of a clearly defined starting point extends well beyond geology. By fixing the meaning and beginning of the Anthropocene in this way, researchers and policymakers from different fields can compare and discuss global environmental changes using a common reference point. Climate scientists can quantify how much the Earth system has departed from Holocene conditions since 1952; historians can trace which social and economic forces drove the acceleration; legal scholars can assess whether existing international frameworks are adequate to the scale of post-1952 change. The research team explained that the Anthropocene could serve as a shared language connecting the natural sciences with the humanities and social sciences, while also helping improve understanding of and responses to environmental crises in areas such as policy, international law, and education. In an era when environmental debates are often fragmented along disciplinary and national lines, a single agreed-upon reference point is a modest but potentially powerful tool.

Professor Buhm Soon Park, who directs the Center for Anthropocene Studies at KAIST, framed the contribution in terms of communication as much as measurement. The Anthropocene, he said, is a common language for understanding how rapidly and extensively humans are changing the Earth. By clarifying its meaning and criteria, he argued, we can compare changes in the global environment more accurately and discuss together how we should respond. He added that he hopes the paper will provide an opportunity to connect diverse fields such as science, policy, education, and the arts in responding collectively to environmental crises. That ambition reflects the center’s own history: Park established it in 2018 and has since pursued research and public discussion of the Anthropocene through publications and translations, lectures, exhibition consulting, and academic conferences. More recently, he has been leading a research project titled A Study of the Great Acceleration in the Anthropocene through the Global Humanities and Social Sciences Convergence Research Support Program of the National Research Foundation of Korea.

The paper itself is a collaborative effort spanning continents and disciplines. Among the international scholars involved are Professor Jan Zalasiewicz of the University of Leicester in the United Kingdom, who served as co-chair of the Anthropocene Working Group, the body that spent more than a decade evaluating whether the Anthropocene should join the official geological time scale; Professor Julia Adeney Thomas of the University of Notre Dame in the United States, a historian whose work examines how political and environmental thought intersect; and Professor Jürgen Renn of the Max Planck Institute of Geoanthropology in Germany, whose institute is dedicated precisely to the study of humans as a geological force. The breadth of this authorship is itself a statement: the Anthropocene, whatever its formal status in stratigraphy, is a problem that no single discipline can define, measure, or solve alone.

The article appeared on September 8, 2026, as part of the special collection The Anthropocene debate in Nature Reviews Earth & Environment, a collection that presents a range of academic perspectives on the definition of the Anthropocene and the continuing debate over whether it should be formally recognized as a geological epoch. The piece is classified as a Perspective, an article type that presents an academic viewpoint and future research directions rather than a single experimental result. Its central claim is likely to resonate far beyond the geology community: that the value of the Anthropocene lies less in its status on an official time scale than in its capacity to organize how humanity understands its own planetary impact. By anchoring that understanding to 1952 and to the measurable rupture of the Great Acceleration, the authors offer a framework in which the environmental crisis can be compared, communicated, and confronted with a shared vocabulary. Whether the broader research community adopts the reference point remains to be seen, but the proposal gives scientists, policymakers, educators, and artists alike a concrete place to stand when they describe the Earth that humans have made.

Subject of Research: A proposed common framework defining the Anthropocene epoch and its 1952 starting point

Article Title: KAIST proposes a common framework for understanding the “Anthropocene,” the Earth altered by humans

Article References: KAIST proposes a common framework for understanding the “Anthropocene,” the Earth altered by humans. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: Anthropocene, KAIST, Great Acceleration, Holocene, geology, Earth system, environmental change, Nature Reviews Earth & Environment, Buhm Soon Park, climate, interdisciplinary research, environmental policy