Timekeepers of geology are on fire – The Atlantic

"Anthropogenic climate change is real, no question," Finney said. But he said geologists did not need a new "basic stratigraphic unit" to discuss this change: they could just tell the year that things were happening. "If you find a pile of garbage somewhere, then" it's the Anthropocene! "No, it's a dump," he said. "It was done in 1940."

Zalasiewicz said that he and his colleagues were going as fast as they could. When the task force started work in 2009, he was "really starting from scratch", he said.

While other working groups have a large body of stratigraphic research, the Anthropocene Working Group has nothing. "We had to spend a lot of time deciding if the Anthropocene was geology," he said. Then they had to decide where his signal could appear. Now, they are looking for evidence that demonstrates it.

"If there is not a good scientific case, we will push it back and let it go in. If we think it's good to formally suggest, then it's up to stratigraphic bodies above us to make the decision. "

Part of the controversy here comes from a simple fact: It is strange that geologists remove the Holocene.

It is easy to write that the Holocene began "at the end of the last ice age," but this distorts the recent geological history of the Earth. Over the course of 2.8 million years, there have been many ice ages: huge glaciers have descended from the Arctic, remade vast expanses of Eurasia and North America, then fell after 100,000 years. After 40,000 years of warmer temperatures, glaciers are coming down again.

This cycle of "frosty" and "interglacial" has occurred about 50 times in the last millions of years. When the Holocene began, it was only another interglacial – although the one in which we lived. Until recently, glaciers were still scheduled to descend in around 30,000 years.

Yet geologists still call the Holocene a time even though they do not grant this term to any of the previous 49 interglacials. He receives special treatment because we live there.

Much of this science is now irrelevant. The vast greenhouse gas emissions of humanity have now so warmed the climate that they have made up for the next ice age. They can even take us out of the current cycle, sending the Earth back to a "greenhouse" climate after the more favorable "cooler" climate during which humans evolved.

For this reason, van der Pluijm wants Anthropocene to completely replace the Holocene. Humans made their first big change in the environment at the end of the last glaciation, when they seem to have hunted the world's largest mammals – the woolly mammoth, the saber-toothed tiger – up to l & # 39; extinction. Why not start then the Anthropocene?

He would even rename the pre-1800 period "Holocene Age" as a consolation prize:

"Humans have redistributed species around the world! let's do what plate tectonics did and move the species, "said van der Pluijm." In the geologic registry, in a few million years, you will suddenly see bones all over the world that have not never been there. "