End of an era

The Anthropocene Working Group has made its recommendation for a "golden spike," the geological site which provides clearest evidence of a geological shift. It's a deep lake in Ontario called Crawford which, meromictic but not anoxic, sediments everything that falls into it, making clear annual bands as calcites precipitate out of summer algal blooms. The bands, widening because of human fertilizer use, mark the c. 1950 turning point the AWG was seeking to anchor, and the captured sediment also contains fly ash pollution with traces of plutonium from atmospheric nuclear tests, burning of fossil fuels and other geologically discernible effects of human activities.

The local fertilizer aside, none of these were the result of human activities nearby, helping cement the claim that these mud bands mark changes of planetary significance. A dozen candidates were considered; it took several votes. The other finalists, a glacial lake in China and a seabed off Japan, offered similar traces but less clearly. Now the proposal goes to other bodies for approval, which is not a given.

Discussions over the last 14 years within the AWG, originally collegial, apparently became less so as they moved from recommending that we recognize an anthropohenic cause to the end of the Holocene to pinpointing a precise marker. As the majority moved from focusing on the industrial revolution to the mid-20th century, when the "Great Acceleration" began, two advocates of earlier datings resigned. Today a third did. In his letter of resignation ecologist Erle Ellis writes

To define the Anthropocene as a shallow band of sediment in a single lake is an esoteric academic matter. But dividing Earth’s human transformation into two parts, pre- and post- 1950, does real damage by denying the deeper history and the ultimate causes of Earth’s unfolding social-environmental crisis. Are the planetary changes wrought by industrial and colonial nations before 1950 not significant enough to transform the planet? The political ramifications of such a misleading and scientifically inaccurate portrayal are clearly profound and regressive. ... 

I have many fond memories and I retain my respect and admiration for all my colleagues in AWG. I remain hopeful that the Anthropocene as a concept will continue to inspire efforts to understand and more effectively guide societal interactions with our only planet. I no longer believe that the AWG is helping to achieve this and is increasingly actively accomplishing the opposite.

These concerns about the ramifications of tying the Anthropocene to particular times and processes, which I've explored in my classes, will doubtless persist. No geological term has ever had implications for "guiding societal interactions within our only planet" - human history is too recent to have registered before. Now that we have, it's unlike that public policy discussions will be bound by the political implications of the stratigraphers' definition of evidence, not to mention artists and religionists.

But, if approved, this does mark the end of a chapter in the story of the Anthropocene. Maybe we leave behind the pretense that the meaning of the Anthropocene for us and our kin is determined by the specificity of the golden spike, a methodological contrivance, if a valuable one. And/or maybe we learn to learn from Crawford Lake, which preserves evidence not just of the last few decades but of the coming and going of First People villages, the Little Ice Age, the arrival of European settlers. As the AWG itself notes

The sediments show how local, historical anthropogenic impacts can be differentiated from those that mark the proposed geological time interval of the Anthropocene, which is concerned with a globally synchronous, broad-scale transformation in Earth’s history.

Earlier research in Crawford's sediment found evidence of a 15th century CE village which has since been rebuilt - a decolonial opportunity which the other finalists would not have afforded.