A small ray of sunshine in the dismal swamp of science journalism from, of all places, The Atlantic…
The Anthropocene Is a Joke
On geological timescales, human civilization is an event, not an epoch.
PETER BRANNEN AUG 13, 2019
Humans are now living in a new geological epoch of our own making: the Anthropocene. Or so we’re told. Whereas some epochs in Earth history stretch more than 40 million years, this new chapter started maybe 400 years ago, when carbon dioxide dipped by a few parts per million in the atmosphere. Or perhaps, as a panel of scientists voted earlier this year, the epoch started as recently as 75 years ago, when atomic weapons began to dust the planet with an evanescence of strange radioisotopes.
These are unusual claims about geology, a field that typically deals with mile-thick packages of rock stacked up over tens of millions of years, wherein entire mountain ranges are born and weather away to nothing within a single unit of time, in which extremely precise rock dates—single-frame snapshots from deep time—can come with 50,000-year error bars, a span almost 10 times as long as all of recorded human history. If having an epoch shorter than an error bar seems strange, well, so is the Anthropocene.
The idea of the Anthropocene is an interesting thought experiment. For those invested in the stratigraphic arcana of this infinitesimal moment in time, it serves as a useful catalog of our junk. But it can also serve to inflate humanity’s legacy on an ever-churning planet that will quickly destroy—or conceal forever—even our most awesome creations.
Perhaps, someday, our signal in the rocks will be found, but only if eagle-eyed stratigraphers, from God knows where on the tree of life, crisscross their own rearranged Earth, assiduously trying to find us. But they would be unlikely to be rewarded for their effort. At the end of all their travels—after cataloging all the bedrock of the entire planet—they might finally be led to an odd, razor-thin stratum hiding halfway up some eroding, far-flung desert canyon. If they then somehow found an accompanying plaque left behind by humanity that purports to assign this unusual layer its own epoch—sandwiched in these cliffs, and embarrassed above and below by gigantic edifices of limestone, siltstone, and shale—this claim would amount to evidence of little more than our own species’ astounding anthropocentrism. Unless we fast learn how to endure on this planet, and on a scale far beyond anything we’ve yet proved ourselves capable of, the detritus of civilization will be quickly devoured by the maw of deep time.
Even worse for our long-term preservation—long after humanity’s brief, artificial greenhouse fever—we’re very likely to return to our regularly scheduled programming and dive back into a punishing Ice Age in the next half-million years.
But what would we leave on the seafloor, where most sedimentary rock is made, where most of the fossils are, and where we have a slightly better chance of recording our decades-long “epoch” in the rocks? Well, many marine sediments in the fossil record accumulated, over untold eons, from the diaphanous snowfall of plankton and silt, at a rate of little more than a centimeter per thousand years. Given this loose metric (and our current maturity as a species), a dozen centimeters of muck seems an optimistic goal for civilization.
A dozen centimeters is a pathetic epoch, but epoch or not, it would be an extremely interesting layer. It’s tempting to think a whisper of atomic-weapons testing would remain. The Promethean fire unleashed by the Manhattan Project was an earth-changing invention, its strange fallout destined to endure in some form as an unmistakable geological marker of the Anthropocene. But the longest-lived radioisotope from radioactive fallout, iodine-129, has a half-life of less than 16 million years. If there were a nuclear holocaust in the Triassic, among warring prosauropods, we wouldn’t know about it.
While Mr. Brannen peppered the article with some carbon-crazy nonsense, he seems to have a George Carlin-worthy sense of civilization’s irrelevance to the Earth. He is also the author of Earth Is Not in the Midst of a Sixth Mass Extinction. He is currently CEJ Scripps Fellow and CU Boulder and actually making an effort to understand “paleoclimate and climate change over geological time scales”. While he clearly buys into most of the alarmist nonsense, he seems to realize that climate change is not an existential threat and that the Earth doesn’t even notice that we’re here.
Mr. Brannen earns a Jon Lovitz award.
via Watts Up With That?
August 14, 2019 at 08:37PM