Anthropocene cancelled: we’re back in the Holocene era

Image: Getty Images
Image: Getty Images
There has been a decade-long year war within the geological community over what to call the epoch we live in right now, and an international panel of two dozen senior geologists has finally delivered its verdict.

We are not living in a new geological epoch after all. The Anthropocene (the "human" era) is now, in George Orwell’s terms, "oldspeak".

"Holocene" used to be the accepted term for the period we still live in, which began when the glaciers started retreating more than 12,000 years ago.

However, as the impacts of human activities on every aspect of the global environment accelerated, a group of (mostly younger) scientists started agitating for a new name: the "Anthropocene".

The new name would take account of the fourfold growth in human population since 1940, the tenfold increase in energy use since 1930 and the accelerating impact of that energy use on climate, and focus our attention better on our own impacts on the Earth system. But it ran into fierce opposition.

To some of the opposition the proposed new name sounded too presumptuous, even arrogant.

Others objected on procedural grounds, and there were definitely some who just thought it was too "woke".

The behaviour of Philip Gibbard, secretary-general of the International Commission on Stratigraphy, didn’t help.

"The decision is definitive," he crowed. "There are no outstanding issues to be resolved. Case closed." Shut up and sit down, in other words.

But this wasn’t an argument between one set of scientists who believe that the activities of human beings are transforming the behaviour of the entire Earth system, and another lot who don’t. The in-house debates were about whether what’s happening deserves the status of a geological epoch, and when it really did start. For example, why did the pro-Anthropocene team pick the 1950s as the start of the epoch?

Yes, there was a surge in fossil fuel burning, fertiliser use and atomic bomb fallout in the ’50s, but why not 5000 years ago, when the global climate prematurely stopped cooling and began climbing instead?

The 10,000-year warm periods that come along about every 100,000 years are called interglacials: the one we are in right now is called the holocene.

Like the 30-odd before, it began with a surge in temperature. Average global temperature rose as much as 7-8°C, even a bit warmer than now.

Global average temperature would then normally start the slow, relentless slide back down until the glaciers began re-forming about 10,000 years later. That is, quite a while ago now, since this interglacial officially started 11,700 years ago. There would already be permanent snow, maybe young glaciers, in northeastern North America.

But this time round the glaciers are not reforming; in fact, they are melting. That’s because about 5000 years ago the average global temperature stopped falling and started rising again.

That made no sense until Bill Ruddiman, an American palaeontologist, pointed out that this was when human beings started farming in a big way. There were only a few million of them at first, but they cut down a lot of trees (carbon dioxide), they tamed a lot of cows and sheep (methane) and they grew a lot of rice (more methane).

A few thousand years of that, and they had released enough greenhouse gas to raise the average global temperature by one full degree Celsius. That’s why we aren’t going back into the next big glaciation right now. In fact, the whole ice age has been cancelled permanently.

Frankly, most people don’t care what the geologists eventually decide to call this episode in the Earth’s long history. Everyone else will call it the Anthropocene because human beings really are now in charge of what happens to the global temperature, the sea level and all the rest of it whether we wanted that job or not. The Anthropocene is not a badge of shame. It is just what the planet is doing right now. We are what the planet is doing right now.

The only relevant question is whether the human race gets to continue in one way or another, which is the way that all evolution works.

More control over the outcome of our own evolutionary experiment, which is what the Anthropocene acknowledges and embodies, is not a bad thing. As Johan Rockstrom, director of the Potsdam Institute for Climate Impact Research, put it: "We are now simply so big and so dominant that we now need to drive the vehicle.

"Currently, we are just sitting there and not really recognising that we are the ones with the levers now. It’s time to use them."

 - Gwynne Dyer is an independent London journalist.