Colin N. Waters et al., “The Anthropocene is functionally and stratigraphically distinct from the Holocene,” Science 351 (January 2016)
Jan Zalasiewicz et al., “The geological cycle of plastics and their use as a stratigraphic indicator of the Anthropocene,” Anthropocene (online January 2016)
Mark Williams et al., “The Anthropocene: a conspicuous stratigraphical signal of anthropogenic changes in production and consumption across the biosphere,” Earth’s Future 4 (online February 2016)
There’s only one place to start this blog, really. Since I finished drafting the book, there have been three big review articles published by members of the Anthropocene Working Group. (The AWG is the panel set up within the International Commission on Stratigraphy to consider whether or not to recommend that a new epoch with the name Anthropocene be added to the geologic time scale.)
Not all of the members of the AWG contributed to the articles; not everyone listed as an author of the articles is a member of the AWG; none of the three articles has exactly the same list of authors (they’re each co-authored by about twenty people). But there’s a lot of overlap. A dozen AWG members signed all three papers: Anthony Barnosky, Alejandro Cearreta, Matt Edgeworth, Reinhold Leinfelder, John McNeill, Will Steffen, Colin Summerhayes, Michael Wagreich, Alex Wolfe—and the three lead authors, Waters, Williams, and Zalasiewicz.
Many of those twelve have published other work on the Anthropocene individually, or in smaller teams (as have other co-authors of the three articles). In those other essays, they’ve taken different stances to one another on various issues. They have different disciplinary backgrounds, and different priorities. This isn’t a uniform mass of Anthropocene true believers, in other words, but an associative network or an affinity group. I’m stressing the point, because one way to misunderstand all of this work is to lump the AWG members’ work together with some other, older writings, and to call that whole heap the “dominant” or the “mainstream” or—if you’re really provincial—the “scientific” version of the Anthropocene.
But all that said, these three papers do form part of a continuous tradition, one that basically goes back to a 2008 paper called “Are we now living in the Anthropocene?” by twenty-one members of the Geological Society of London (its signatories included the three lead authors of the papers at hand). Prominent in that tradition are two collections of essays. First, a 2011 issue of the Philosophical Transactions of the Royal Society called The Anthropocene: A New Epoch of Geological Time? Second (the real landmark; the first collection was in truth quite miscellaneous) a book called A Stratigraphical Basis for the Anthropocene, published by the Geological Society of London in 2014. There’s been a run of new papers since then. A key one, as I see it, is Colin N. Waters et al., “Can nuclear weapons fallout mark the beginning of the Anthropocene Epoch?” in the Bulletin of the Atomic Scientists (2015).
And now we have three more. Erinaceus deprecates two-thousand-word blogposts, so there’s only room in this post to talk about the first of them. Waters et al. (“The Anthropocene is functionally and stratigraphically distinct…”) is I suppose both the most significant and the least novel of the three. It’s important mainly for the way that it consolidates and re-emphasises work that’s gone before, but nonetheless it’s right that this should have been the one that was reported in the newspapers. If you wanted to read just one paper as an introduction to the enterprise of the AWG, this would be the one to pick.
The bulk of the review is a relentless nine-page survey—gripping, dismaying, and abundantly footnoted—of the total scale of worldwide ecological transformation and destruction over the course of recent decades, with an eye to the traces that that chaos will leave behind in the remote future. That’s the data on which the whole concept of the Anthropocene is founded.
The crucial thing that happens in Waters et al., though, is that twenty-five of the AWG’s members go further than they’d gone before towards giving their answer to the question that the group was set up to investigate. That is, towards saying yes, “the Anthropocene” meets the criteria required for its formalization as a new geological epoch. Here’s the killer line:
Distinctive attributes of the recent geological record support the formalization of the Anthropocene as a stratigraphic entity equivalent to other formally defined geological epochs. The boundary should therefore be placed following the procedures of the International Commission on Stratigraphy.
Caveats follow immediately: “If such formalization is to be achieved, however, further work is required … it needs to be determined how the Anthropocene is to be defined … this is linked to the question of when exactly the Anthropocene may be determined to begin.” Geological intervals can be defined simply by assigning them a start date (1945 is one contender in this case), but usually you want to pick some tangible, widespread, dateable trace in stratified layers of rock to serve as their starting point. That’s still a work in progress—though a lot has been done towards it in the last few years.
And in any case, should the Anthropocene be formalized at all, or left as “an informal … geological time term”? (Left informal “as the Precambrian and Tertiary currently are,” Waters and co. write, though that’s a rather misleading comparison.) “This is a complex question,” as they delicately put it: “unlike other subdivisions of geological time, the implications of formalizing the Anthropocene reach well beyond the geological community.”
The paper isn’t just a hardening of the previous consensus, however. There’s one important conceptual shift. The AWG papers that preceded it typically noted three broad alternatives for the dating of the Anthropocene: it could be said to have begun in the mid-twentieth century; at the time of the British Industrial Revolution around 1800; or at some earlier, pre-industrial time. The most recent of those options has been steadily emerging as the favoured one, and this paper carries on that glide towards consensus. But, for the first time, it identifies four possible categories of starting date. The pre-industrial candidacy has been broken into two: either an Anthropocene thousands of years old, or one stemming from “the Columbian Exchange of Old World and New World species associated with colonization of the Americas.”
That innovation is the consequence of this paper. It looks as if the argument made in Simon Lewis and Mark Maslin’s “Defining the Anthropocene” has now become incorporated into the AWG members’ thinking. It got there via a distinctly crotchety exchange in Nature and the Anthropocene Review, but it got there. It’s a very good thing that the Columbian Exchange has gained more prominence in the story of the new epoch—or at least it will be, once the idea of an early modern turning point in the birth of the Anthropocene gets disentangled from the Ruddiman hypothesis. But that’s a topic for another post.
One last thing.
I think that the work condensed in “The Anthropocene is functionally and stratigraphically distinct from the Holocene” is the single most generative starting point for ecological politics today. But in that article there’s also this, at the opening of a section headed “Human drivers of stratigraphic signatures”:
The driving human forces responsible for many of the anthropogenic signatures are a product of the three linked force multipliers: accelerated technological development, rapid growth of the human population, and increased consumption of resources.
That’s the sort of thing, right there, that makes politically minded opponents of the idea of the Anthropocene grind their teeth. And rightly so. The day we really have a political geology will be the day when those three factors—the advancing technological frontier, demographics, and consumption patterns—no longer look like the ultimate drivers of the “driving human forces” of the Anthropocene epoch. When, instead, we can follow the causal chain all the way from stratigraphic signals to changes in relations of production. That’s the link among those forces of technology, demography, and consumption that’s still missing, for now, from the AWG’s analysis. And, further, once that chain is completed we’ll be able to see that in fact it’s only one half of a circuit: we’ll be able to follow the path back again from relations of production to the physical dynamics of the earth system in which they’re embedded.
More to follow!