The word Anthropocene, unknown twenty years ago, now appears in the titles of three academic journals, dozens of books, and hundreds of academic papers, not to mention innumerable articles in newspapers, magazines, websites, and blogs. There are exhibitions about art in the Anthropocene, conferences about the humanities in the Anthropocene, and novels about love in the Anthropocene. There is even a heavy metal album called The Anthropocene Extinction. Rarely has a scientific term moved so quickly into wide acceptance and general use.
Behind what might appear to be just a trendy buzzword are important scientific discussions that have radical implications for the future of life on Earth. Three leading authorities on the science of the Anthropocene express the issues clearly:
Socialists cannot ignore a change of this magnitude, or treat it as just one aspect of our program. As the Brazilian ecosocialist and atmospheric scientist Alexandre Costa writes, “The fight to avoid a catastrophic outcome to this crisis engendered by capitalism is the fight to safeguard the material conditions for survival with dignity of humankind…. Socialism is not possible on a scorched Earth.”2
In 1995, Paul Crutzen, then vice-chair of the International Geosphere-Biosphere Program (IGBP), received a Nobel Prize for showing that widely used chemicals were destroying the ozone layer in earth’s upper atmosphere, with potentially catastrophic effects for all life on Earth. In his Nobel acceptance speech, he said that his research on ozone had convinced him that the balance of forces on Earth had changed dramatically. It was now “utterly clear,” he said, “that human activities had grown so much that they could compete and interfere with natural processes.”3 Over the next five years that insight developed until, at an IGBP meeting in 2000, he argued that human activity had driven the earth into a new geological epoch, which he proposed to call the Anthropocene.
Crutzen and Will Steffen, then executive director of the IGBP, minced no words in describing the Anthropocene as a qualitative and dangerous change in the Earth system:
A no-analogue state. Planetary terra incognita. Unprecedented and unsustainable. These phrases are not used lightly: the earth has entered a new epoch, one that is likely to continue changing in unpredictable and dangerous ways.
This radical transformation was first extensively described by the IGBP in 2004, in Global Change and the Earth System, a broad synthesis of scientific knowledge about the state of our planet that remains the most authoritative book on the Anthropocene.5 Since then, a great deal of scientific discussion has focused on a question that book did not answer: When did the Anthropocene begin? Of course this has involved technical discussions among experts in various disciplines, but it is not just a technical question. Technical studies can determine when an asteroid hit our planet or when an ice age ended, but a discussion of when human society pushed the Earth system into a no-analogue state must address social, economic, and political issues.
There is a reciprocal process here. Examining social, economic, and political developments can help identify social changes that might have changed the Earth system, and determining when radical physical changes in the Earth system happened provides a basis for determining which human activities were responsible, and thus what measures humans might take to prevent the change from reaching catastrophic proportions. In this article I offer an overview of the issues and stakes in the “when it happened” debate.