In September 2017, an esteemed group of scientists — geologists, physicists, chemists, archaeologists, geographers, biologists, and oceanographers — published a milestone paper in a relatively new journal called Anthropocene. Launched just four years previously, the journal followed the creation of its titular concept, but preceded the official declaration of that concept’s reality.
The Anthropocene is the notion that this particular time on planet Earth, the time when humans are changing global ecosystems and geophysical patterns in profound ways, deserves its own name. The Holocene is the name given to the last 10,000 years, after the glaciers melted and we restlessly nomadic humans began to settle down and invent houses, agriculture, cities, nations, economics and technology.
The Anthropocene is the result.
In the article, which is entitled “The Working Group on the Anthropocene: Summary of evidence and interim recommendations,” the scientists declare the Anthropocene to be “stratigraphically real.” Here is what these words mean, in practical terms: we are leaving an indelible, geological mark on the planet.
Imagine a time, millions of years from now, when humans no longer exist (at least in our current form — perhaps we will have become clouds of sentient energy, wafting through a multi-dimensional cosmos, with vague memories of the blue-green planet of our birth). Imagine that the geologists of that time, who have evolved from one of today’s lower mammals, start digging. What will they find?
At a certain layer of rock, which will be proven to be roughly the same time, all over planet Earth (or whatever they shall call their home in the solar system), the geologists will discover evidence of a profound transformation. They will find sudden changes in erosion patterns, and in the way sediments shift along ancient river beds. They will find molecular evidence of changes in the carbon cycle, the nitrogen cycle, the global dispersion of phosphorous and other elements. They will note a precipitous (in geological terms) rise in sea levels, and a rapid decline in polar ice. They will find the fossil evidence of extraordinary species that once walked the planet, but suddenly went extinct; and they will find evidence of other species, never before seen in the fossil record, that suddenly appear everywhere, in massive numbers.
It is unlikely that these future geologists will know that we called the new animals dogs and cats, cows and chickens, though they will be able to trace their evolutionary roots to wolves, larger cats, wild oxen, and a jungle bird from the area now called Southeast Asia. They will certainly find bountiful fossil evidence of our species, homo sapiens. But they will have no way of knowing that we called the extinct species elephant, pangolin, gorilla, rhino.
Finally, they will find copious “technofossils”, the geologically preserved remains of homo sapiens’ technology and industry. These might include plastics, buckyballs, graphene. The most surprising find will be the sudden appearance of plutonium, an element that occurs very rarely in nature, among deposits of uranium, but that suddenly will be seen as lightly distributed over large areas, “as though it had rained from the sky” they might say — which is exactly what happened.
The arrival of the Anthropocene as a concept appears to concern the scientific analysis of the recent past, because much of the academic debate around its introduction has circled around when, exactly, to declaim its historical beginnings. Should one draw the line in geological time at 1945, when the first atomic bombs began their rain of uranium and plutonium and other radioactive fallout? Or should we dial the clock back a few thousand years, to the global spread of agriculture?
In any event, the principal value of the Anthropocene is not as a tool for looking back in time, but for looking forward. Understanding that we have altered certain mega-processes in the Earth’s systems beyond restoration, that the stable and predictable conditions of the Holocene’s ten thousand years are in some definitive sense over, is a great mental aid in thinking about the future.
We are not just constantly changing our human world; we are creating a new Earth.