Crutzen and his colleagues — Will Steffen of the Australian National University, Canberra, and John R. McNeill of Georgetown University — concede that those early folks had a significant impact, but they argue that the real turning point began in the late 18th century with the industrial revolution, and it reached a new level at the end of the Second World War. They call the modern period the Great Acceleration of the Anthropocene, when humans began to overwhelm their planet.
In their own words:
"The Great Acceleration is reaching criticality. Enormous, immediate challenges confront humanity over the next few decades as it attempts to pass through a bottleneck of continued population growth, excessive resources use, and environmental deterioration. In most parts of the world the demand for fossil fuels overwhelms the desire to significantly reduce greenhouse gas emissions.
"About 60 percent of ecosystem services are already degraded and will continue to degrade further unless significant social changes in values and management occur. There is also evidence for radically different directions built around innovative, knowledge-based solutions. Whatever unfolds, the next few decades will surely be a tipping point in the evolution of the Anthropocene."
Those last couple of sentences are among the few encouraging words in their paper. Maybe we don't have to stumble down this path forever. But given the vast gaps between the haves and the have-nots, the relentless reach for a higher standard of living, the exploding need for more energy at seemingly any cost, it's hard to be optimistic.
As they note in their paper, "To develop a universally accepted strategy to ensure the sustainability of Earth's life support system against human-induced stresses is one of the greatest research and policy challenges ever to confront humanity. Can humanity meet this challenge?"
Lee Dye is a former science writer for the Los Angeles Times. He now lives in Juneau, Alaska.