As an addendum, the author, Peter Brannen, published another article with The Atlantic titled "What Made Me Reconsider the Anthropocene" four days ago.<p>In it, he responds to criticism and ultimately comes to the conclusion that - even if no trace of humanity is left (no civilization, tools, etc) in "deep time" - the biosphere itself has been changed by humanity, and that gives the concept of the Anthroprocene validity.<p><a href="https://www.theatlantic.com/science/archive/2019/10/anthropocene-epoch-after-all/599863/" rel="nofollow">https://www.theatlantic.com/science/archive/2019/10/anthropo...</a>
>If, in the final 7,000 years of their reign, dinosaurs became hyperintelligent, built a civilization, started asteroid mining, and did so for centuries before forgetting to carry the one on an orbital calculation, thereby sending that famous valedictory six-mile space rock hurtling senselessly toward the Earth themselves—it would be virtually impossible to tell.<p>I consider this claim to be complete nonsense. Change my mind.
There are 4 billion year old rocks still on the earth to be found. 7,000 years of civilization is not going to be completely erased in a few million.
It's obvious that human history is very short but it's less obvious that all of our buildings and trash will be so hard to find underground in five million years or so.<p>Wouldn't there at least be some places where ruins or landfills were largely exposed? And aren't there lots of materials that would stand out since they degrade slowly?<p>For example, what is going to happen to all of the concrete and steel in Manhattan in the course of five million years? Will it really be compressed to a thin layer that is barely noticeable or something?
>Will our influence on the rock record really be so profound to geologists 100 million years from now, whoever they are, that they would look back and be tempted to declare the past few decades or centuries a bona fide epoch of its own?<p>Yes, there will be a thin but noticeable layer of hydrocarbons and odd pollution signatures in the crust that will act as a permanent geologic record of our existence.
The holocene always struck me as odd. Here we have the final geologic epoch, and it's 10,000 years old, and every other geologic epoch is ~50M years long. And it just happens to coincide with the rise of our species, who just happens to be the one creating the taxonomy.<p>Paleohistory is pretty fascinating, and it's easy to forget just how small we are on this big earth and how much things differ from today. For example:<p>We're technically in an icehouse age. An icehouse age is defined as "any period of time where glaciers exist <i>anywhere</i> on the planet". For about 80% of geologic time, there is no such thing as a glacier, or of snow and ice for that matter. The entire earth's surface is above freezing, even the North and South poles. What we know of as an "ice age" (a glaciation) is a feature only of icehouse states. We currently happen to be in an interglacial of an icehouse age, which is why we think of this as being a warm period. But geologically, the earth is <i>well</i> below its temperature average.<p><a href="https://en.wikipedia.org/wiki/Greenhouse_and_icehouse_Earth" rel="nofollow">https://en.wikipedia.org/wiki/Greenhouse_and_icehouse_Earth</a><p>It's likely that the earth has completely frozen over on at least two occasions, with the entire planet being encased in a gigantic ice sheet like Europa:<p><a href="https://en.wikipedia.org/wiki/Snowball_Earth" rel="nofollow">https://en.wikipedia.org/wiki/Snowball_Earth</a><p>The larger of these two incidents may have been triggered by the evolution of photosynthesis and the addition of oxygen into the earth's atmosphere, which also likely caused a major mass extinction among the dominant anaerobic bacteria of the time:<p><a href="https://en.wikipedia.org/wiki/Great_Oxidation_Event" rel="nofollow">https://en.wikipedia.org/wiki/Great_Oxidation_Event</a><p>Sea level over time has fluctuated by 300-400 meters. That means that anything at an altitude of less than about 1000 feet (which is the vast majority of human settlements) was once underwater. (Well, technically <i>land</i> level fluctuates more than sea level, so most of these low-lying areas are actually sediment weathered off of nearby mountains.)<p><a href="https://en.wikipedia.org/wiki/Past_sea_level" rel="nofollow">https://en.wikipedia.org/wiki/Past_sea_level</a><p>There've been some massive outburst floods in the past, like the draining of Glacial Lake Missoula (a pleistocene lake roughly half the volume of Lake Michigan, held in by an ice dam on the Clark River nearly 2000 feet tall) which released an outflow 13 times the size of the Amazon River:<p><a href="https://en.wikipedia.org/wiki/Missoula_Floods" rel="nofollow">https://en.wikipedia.org/wiki/Missoula_Floods</a>
It seems to me this person is missing the point. When people talk about Anthropocene, they're not talking about geological or fossil evidence left behind by humans in million of years. Anthropocene refers to the Holocene or the sixth mass extinction on the planet.<p><a href="https://en.wikipedia.org/wiki/Holocene_extinction" rel="nofollow">https://en.wikipedia.org/wiki/Holocene_extinction</a>