With Anthropocene Working Group (AWG) Chair Zalasiewicz as lead author and 24 other members of the group listed as co-authors, “When did the Anthropocene begin?” has been received as a trial balloon for the AWG’s final recommendation to the International Commission on Stratigraphy (ICS). (This impression is perhaps confirmed by a more elaborate and recent version of the argument by Waters et al. that is acknowledged to be an official contribution of the AWG, but which I don’t consider here.) Varied responses to the article are indicative of how the popularity of the Anthropocene idea and public turmoil regarding anthropogenic climate change are intruding into the official deliberations among geologists about the Geological Time Scale (GTS). Additional unusual pressure stems from tension between separate academic disciplines brought together for the topic of the Anthropocene and seeing in it reason to challenge established research protocols, including those in other fields. Geologists are not being left to their own devices. Hamilton, for example, insists that the development of Earth System science at more or less the same time that anthropogenic global warming became a subject of research and a matter of public concern constituted a Kuhnian paradigm shift in Earth sciences. Noting the interdisciplinary composition of the AWG, he claims that adjudicating the position of the Anthropocene in the GTS should involve participants from multiple Earth sciences and an attention not only to the geological record but to fundamental changes in the functioning of the Earth System. In contrast, Finney and Edwards’s refutation of “When did the Anthropocene begin?” polices strictly the propriety of the ICS, noting that changes to the Earth System do not necessarily correspond to divisions of the GTS.
In spite of this surfeit of context, the objective of the article is quite narrow. On the basis of the already considerable literature on the topic of the Anthropocene, the authors propose to identify an initial stratigraphic time boundary that is practically “singular, globally synchronous, and commonly understood” (2). They assert that such a proposal need not address whether the Anthropocene should be formalized in the GTS. Continued use of the term as “an unofficial stratigraphic time” also warrants a coherent, unambiguous designation. And they insist that naming a lower boundary does not imply that further inquiry into the Anthropocene cannot take place on the Holocene side of the divide (and vice versa, if the Anthropocene is considered an epoch rather than an age within the Holocene). They evaluate three potential durations: an early Anthropocene associated primarily with the spread of agriculture thousands of years ago, an industrial Anthropocene dated to approximately the beginning of the nineteenth century, and the mid-twentieth century period that earlier writings on the Anthropocene called the Great Acceleration.
Citing Ellis among others, they acknowledge that thousands of years ago humans already influenced the Earth System, but they are ultimately not persuaded by such an early date because the “significance of the Anthropocene lies not so much in seeing within it the ‘first traces of our species’ (i.e. an anthropocentric perspective upon geology), but in the scale, significance and longevity of change (that happens to be human-driven) to the Earth system” (4). The industrial Anthropocene is more convincing because it achieves a “more considerable perturbation than that achieved in pre-industrial times.” They find, however, that setting the initial boundary of the Anthropocene in eighteenth century industrialization would not be stratigraphically effective because, as in the earlier period, the evidence is diachronous and distributed unevenly. The most recent of the three prospects affords the authors a number of stratigraphically significant signs such as the global dispersal of “artificial radionuclides” from nuclear explosions, lead waste (from gasoline) in polar ice, the carbon isotope signal associated with ~120 ppm increase in CO2, shore to shore oil-spill residue from rapid increases in (accident-prone) marine oil-tanker traffic, a “spate of urbanization” that will be recorded in the land, “technofossils” such as mobile phones that extend the evidence past mid-century, and so on (4-5).
Because the nuclear explosions starting in 1945 dispersed “artificial radionuclides worldwide,” they propose the following singular, globally synchronous, and commonly understood boundary. The Anthropocene can be said to begin “historically at the moment of the detonation of the Trinity A-bomb at Alamogordo, New Mexico at 5:29:21 Mountain War Time … July 16, 1945 … This would have a parallel with the Cretaceous-Paleogene boundary which, although defined by “Global Boundary Stratotype Section and Point” (GSSP–called a “golden spike”) at El Kef, Tunisia, has been expressly placed at the moment of impact of the meteorite on the Yucatan Peninsula” (5). The difference between the location in Tunisia and the instant of the asteroid strike refers to a technical distinction between a golden spike placed to mark “rock units” (Finney and Edwards 5) and a “Global Standard Stratigraphic Age” (GSSA) marker that is represented in years relative to the present. Zalasiewicz et al. claim that in the case of the Anthropocene a GSSP does not provide a “practical advantage over a GSSA” (5).
To capture the appeal and utility of a precise moment in time, the authors cite a sign of anthropogenic causes for climate change that is resulting in the sixth great extinction and compare it to the Chicxulub Asteroid, which was the direct cause for the extinction of the dinosaurs. This association of the Trinity test with an asteroid striking Earth illustrates a challenge of identifying human activity as a dominant geological force. It is difficult to establish a hard and fast distinction between, to borrow from Ellis, sociocultural niche construction in the Holocene and, with apologies to Ellis, sociocultural niche destruction in the Anthropocene.
Ellis is a co-author of “When did the Anthropocene begin?” Readers of his ESA Centennial Essay will discern his influence in the article’s description of pre-industrial anthropogenic influences on the Earth System. But the argument for a mid-twentieth century Anthropocene ultimately runs counter to his theoretical demonstration of the ways that today’s unprecedented “scale, significance and longevity of change to the Earth system” (Zalasiewicz et al. 6) can be linked to evidence of human sociocultural niche construction throughout much of the Holocene and even earlier.
In “Defining the epoch we live in,” Ruddiman, Ellis, Kaplan, and Fuller respond directly to the choice of July 16, 1945:
Selecting 1945 as the start of the “Anthropocene” would implicitly omit … extensive agricultural and early-industrial alterations. Does it really make sense to define the start of a human-dominated era millennia after most forests in arable regions had been cut for agriculture, most rice paddies had been irrigated, and CO2 and CH4 concentrations had been rising because of agricultural and industrial emissions? And does it make sense to choose a time almost a century after most of Earth’s prairie and steppe grasslands had been plowed and planted? Together, forest cutting and grassland conversion are by far the two largest spatial transformations of Earth’s surface in human history. From this viewpoint, the “stratigraphically optimal” choice of 1945 as the start of the Anthropocene does not qualify as “environmentally optimal.” (39)
I have cited them at length to display their rhetorical questions along with this last reference to “environmentally optimal,” which I imagine may be an instance of interdisciplinary push back against the geological priority of a synchronic marker to describe phenomena that are more accurately identified diachronically. Convinced that the term Anthropocene will persist in spite of disagreements over its province, they recommend it be used informally with a small “a,” which would allow for appropriate modifiers such as “early agricultural” or “industrial” (39). Such utility would guard against presentist misrepresentations of the long historical record of anthropogenic environmental change that they summarize in counterpoint to “When did the Anthropocene begin?”
“Defining the epoch we live in” makes its case against the recent Anthropocene – or for an atomic anthropocene – with a succinct but detailed historical account of massive change to the Earth’s surface effected by human activity over thousands of years. Not addressed directly is the contention that the measure of the Anthropocene is the “considerable perturbation” of the Earth system. “Perturbation” is an alarming word choice more in concert with representations of the Anthropocene as a catastrophic rupture that has divorced Earth from – for us and many other species – the more hospitable climes of the Holocene. Ellis adopts an opposite stance. A signatory to An Ecomoodernist Manifesto’s pronouncements about the possibility of a “good, even great Anthropocene,” Ellis insists we should not regard it as a crisis (2011). Its difference from the Holocene is in degree and not kind. I take his optimism to have a theoretical basis in “Ecology in an anthropogenic biosphere.”
A key claim of the Ellis essay we are examining in this series of posts is that human ultrasociality has long been characterized by practices and organizations of shared intentionality that mean human niche construction is sociocultural. This finding informs Ellis’s contention that defining human ecological sustainability according to natural limits or the “carrying-capacity” of the Earth (a la Malthus or The Population Bomb) is mistaken. Encouraged as I am to be directed away from romantic conceptions of nature as essentially wilderness without us, I am also disturbed to ask if Ellis’s theory of sociocultural niche construction allows not just for maladaptive developments – he is emphatic that it does just as he reiterates his recognition of the devastating effects of anthropogenic climate change – but for the possibility of maladaptations that would irreversibly transform the conditions in which we endeavor to exercise shared intentionality? In other words, can Ellis’s account of early anthropocene “cultures of nature” be reconciled with accounts of the Anthropocene that define it on this side of a rupture from the Holocene?