[:es]
On geological timescales, human civilization is an event, not an epoch
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.
So what to make of this new “epoch” of geological time? Do we deserve it? Sure, humans move around an unbelievable amount of rock every year, profoundly reshaping the world in our own image. And, yes, we’re currently warping the chemistry of the atmosphere and oceans violently, and in ways that have analogues in only a few terrifying chapters buried deep in Earth’s history. Each year we spew more than 100 times as much CO2 into the air as volcanoes do, and we’re currently overseeing the biggest disruption to the planet’s nitrogen cycle in 2.5 billion years. But despite this incredible effort, all is vanity. Very little of our handiwork will survive the obliteration of the ages. If 100 million years can easily wear the Himalayas flat, what chance will San Francisco or New York have?
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.
What paltry smudge of artifacts we do leave behind, in those rare corners of the continents where sediment accumulates and is quickly buried—safe from erosion’s continuous defacing—will be extremely unlikely to be exposed at the surface, at any given time, at any given place, tens of millions or hundreds of millions of years in the geological future. Sic transit gloria mundi.
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.
Seguir leyendo: The Atlantic
Imagen de Rilson S. Avelar en Pixabay
[:ca]
On geological timescales, human civilization is an event, not an epoch
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.
So what to make of this new “epoch” of geological time? Do we deserve it? Sure, humans move around an unbelievable amount of rock every year, profoundly reshaping the world in our own image. And, yes, we’re currently warping the chemistry of the atmosphere and oceans violently, and in ways that have analogues in only a few terrifying chapters buried deep in Earth’s history. Each year we spew more than 100 times as much CO2 into the air as volcanoes do, and we’re currently overseeing the biggest disruption to the planet’s nitrogen cycle in 2.5 billion years. But despite this incredible effort, all is vanity. Very little of our handiwork will survive the obliteration of the ages. If 100 million years can easily wear the Himalayas flat, what chance will San Francisco or New York have?
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.
What paltry smudge of artifacts we do leave behind, in those rare corners of the continents where sediment accumulates and is quickly buried—safe from erosion’s continuous defacing—will be extremely unlikely to be exposed at the surface, at any given time, at any given place, tens of millions or hundreds of millions of years in the geological future. Sic transit gloria mundi.
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.
Seguir leyendo: The Atlantic
Imagen de Rilson S. Avelar en Pixabay[:]
