The Human Epoch The Anthropocene Epoch as Earthly Modernity

Transcriber: Amanda Zhu
Reviewer: Rhonda Jacobs

On my way to work, I walk
through a typical new England woodland

and see enormous trees -

pine, oak, beech, hickory, maple -

they all grew back like weeds
on what had once been a farm,

a patchwork of grassy pastures
and cultivated fields.

My footpath wends its way
around a small pond

that once watered livestock,

past an old cellar hole,

and through old stone walls
that crisscross beneath the forest canopy.

During each of my pedestrian commutes,

I’m witness to the ruins
of an abandoned agricultural civilization

and the power of wild nature
to reclaim the land.

I live in a distinctly younger
epoch of modernity.

The word “modern” comes to us
from the Latin “modo,”

meaning “just now” as opposed
to some previous condition or mode.

To become modern
is to cross a boundary in time.

In this place between
an older culture of rural farmers

energized by manual labor,
draft animals, and fuel wood

and a younger culture of urbanizing,
industrial, more mobile people

energized mainly by fossil fuels.

When I get to my office
at the university, however,

to teach Earth System Science,

the spatial scale shifts
from that of New England farmsteads

to that of the entire globe.

And what does modernity look like
at that scale to a geoscientist?

Well, it looks like
a lot of familiar things to you:

rapid climate changes
fueled by greenhouse gas transfers,

resulting in the melting
of glaciers and permafrost,

the expansion of drylands,

and the intensification of storms.

It looks like ecosystem collapses,
resulting in a sixth mass extinction

involving both terrestrial
and marine settings.

And it looks like oceanic transformations,

resulting in sea level rise,

warming waters, diminished pack ice,

and a carbonized chemistry
with more acid and less oxygen.

This geophysical and geochemical modernity

also includes a human component.

An overwhelmingly dominant species,

ours, Homo sapiens,

spread into every habitat

and being in direct or indirect control
over nearly every other species.

It includes deliberate human makeovers
of land and sea from top to bottom,

often called “land use,”

accompanied by inadvertent, often chaotic
repercussions that we hadn’t planned on.

It includes never-seen-before
synthetic materials

like plastics,

novel chemicals

like the chlorofluorocarbons
that nearly destroyed the ozone layer,

and radionuclides like plutonium-239,

which dusted the entire planet

during the atomic bomb testing
I remember as a child.

The first of these three megatrends,
these modern megatrends -

climate change, ecosystem collapse
and oceanic changes -

are nothing new to planet Earth.

In fact, these are the criteria

that typically separate epochs
on the geological calendar.

It’s the last three
of these modern megatrends,

the human dominance, the human makeovers,
and the human inventions,

that are truly unique with respect
to the long-haul of Earth history,

which began a long time ago,

4.6 billion years ago.

But is there a single global thing
that holds these six megatrends together -

holistically and historically?

The answer is a clear “yes,”
in both space and time.

In space, that thing is the entire planet.

The close examination
inclusive modeling of which

leads to our understanding

of a spinning,

wobbling,

tilting,

orbiting,

sloshing,

living

spheroid

of gases liquids and solids.

So that’s the part about space.

In time, that thing is the newest epoch
of the geological time scale,

the almost-official Anthropocene epoch.

It’s an idea evoked 20 years ago,
in the year 2000,

by Paul Crutzen and Eugene Sturmer

to highlight the idea

that modern Earth is distinct
from all previous states.

It’s an epoch name for us human beings
not out of vanity or hubris

but for the astonishing power we’ve used
to literally change the face of the Earth.

It’s a word that
according to Google Analytics

has been accelerating in popularity,

even as the popularity
of the word “environmentalism”

is diminishing a little bit.

It’s a word that
through categorical thinking

will help create a paradigm shift

in the way we think about nature,
the wild, and the environment,

a word that I hope will help us return
to an ethical and sustainable future.

Consider three examples of news stories
from the modern United States

within the last few months:

raging forest fires in the American West,
especially in California;

the return of great white sharks
to New England,

especially Outer Cape Cod;

the drenching catastrophic floods
along the US Gulf Coast,

especially in New Orleans.

Now, all three of these things
are truly wild responses -

wildfires, wild carnivores, wild waters -

is something that we humans have done.

Ultimately, they can be traced back
to human behavior,

natural human behavior.

The wildfires come
from the baking droughts

we’ve intensified by global warming;

the wild shark populations

comes from the rising population of seals
that we’ve protected;

the wild waters

are happening on a landscape
that’s sinking beneath the sea

because we’ve starved the land

of the sediment it needs
to stay above sea level.

But what’s the root cause of all this?

To get there,

we have to work our way backwards
through a chain of causality,

and I’ll use the case
of wildfires as an example.

The fires are more intense

because the regional climate
is drier in summer

because the prevailing
hemispheric circulation has changed

because the average temperature
of the troposphere

is almost two degrees warmer

because humans have transferred
enormous amounts of carbon

from the terrestrial
component of our system

to the atmospheric component

because we enjoy the advantages

of cheap energy provided by fossil fuels
and of global deforestation

because our human psyches are governed
by instinctual animal behaviors

that emerged during human evolution.

Two of our behaviors
are particularly important.

The first is our natural drive
to have families

and provide for them as much as we can.

The second is our natural
cognitive intelligence,

which allows us to figure out
how things work

and invent new and better things,

such as tools, crops, materials,
medicines, homes, and sources of energy.

The motivation to improve our lives
combined with our flexible intelligence

gave rise to science,

which gave rise to engineering,

which gave rise to the power
to literally remake the planet.

The rest of this natural behavior

has been a human makeover
of the Earth’s surface,

part of which has been very deliberate,

like the building of cities,
the taming of rivers,

and the killing of carnivores;

and part of which has been
completely inadvertent,

like the fouling of our nests
and the raising of Earth’s temperature.

Regardless of intent,

human beings are now the dominant
geologic agent operating on the planet.

That’s a fact.

Moving mass at a greater rate
than the glaciers of the last ice age

and the rivers
of familiar geologic history,

global modernity
looks strikingly different

from the regional human history
of the previous Holocene epoch,

which began about 11,700 years ago.

Thus, we geoscientists have no choice
but to create an official new epoch,

and we’re nearly done with the process.

And the label “Anthropocene”

is simply the best one
we’ve come up with so far.

Various dates for the beginning
of this epoch of geologic modernity

have been suggested and hotly debated.

Some proponents favor the onset
of agriculture and early civilizations

about 10,000 years ago,

some favor the onset
of maritime colonialism

in the late 15th century,

some favor the rise
of the industrial revolution

in the late 18th century,

and most favor the global explosion
and great acceleration

of science, technology, human populations,

urbanization, energy use,
and land conversions

in the mid-20th century.

This last candidate for the beginning
of the Anthropocene epoch

is the best one

because it is ubiquitously
and clearly marked

by the radioactive dust from atomic bombs,

major excursion in chemical cycles,

and the deposition of sediment
with plastic trace fossils

the world over.

The Anthropocene
finds its ancient counterpart

in the 66 million-year-old
Paleocene epoch,

which was also strikingly different
from its predecessor

ruled by the dinosaurs.

In this earlier case,

the change came not from human technology

but from an asteroid impact

combined with colossal volcanism
about 67 million years ago

that initiated a cascade
of global disruptions

that gave mammals a chance
to start evolving into humans.

This earlier transition

is ubiquitously and clearly marked

by a concentration of cosmic dust,

geochemical excursions,

and the deposition of sediment
with different trace fossils.

So why does naming a new epoch matter?

Because as Aldous Huxley once wrote,

“Words are the channels
through which thought flows,”

some of our most influential words
are categorical labels;

for example, good versus bad,
old versus new, us versus them,

fruit versus vegetables,
or Democrats versus Republicans.

Thinking in the box
versus thinking out of the box

is also a categorical distinction -

though this practice can lead
to dangerous false dichotomies

and implicit biases -

on the whole that
it’s an essential tool for science,

the basis of all classifications.

In 1963,

I watched one of my heroes,
Rachel Carson, address the nation

on our family’s small black-and-white TV.

She was featuring her book
“Silent Spring.”

Seven years later, in 1970,

I participated in the first Earth Day
celebration as a college student.

Between these dates,

I witnessed the rise

of a new categorical meme
in popular culture:

environmentalism -

a new way of thinking
about chemical pollution,

endangered species,

and wilderness conservation,

all wrapped up into one bigger thing.

The single word “environmentalism”
channeled our thinking

to create a profound social change

in a world that had not yet begun
to concern itself with climate change.

Well, clearly, today we need
a new categorical meme

to channel our thinking

about an even larger
and more profound global concern:

the recognition that the fate
of the entire planetary surface

lies in human hands.

Is climate change that new meme?

It seems that way

given all the scientific, media,
and political attention,

but for me, and despite its popularity,

climate change is too small a concept

because climates
are by definition regional

and have always come
from the geological underground

via the tectonic rearrangements
of continental plates

and the chemical transfers

between Earth’s solid, liquid,
and gaseous reservoirs.

Climate change, ecosystem collapse,
oceanic transformations,

these are merely the big pieces
of a larger pie.

The holistic or mechanistic view
of that global pie is what I teach,

Earth system science.

The historic or narrative view of that pie
is Earth system history,

its latest chapter
being the Anthropocene epoch.

For me, the new meme we need
is the word “Anthropocene.”

We must be brave enough to admit

that we live in a new world
of our own making.

Only then can we stop blaming nature
and stop blaming ourselves

and return to sustainable ways
through human invention.

To help you understand this new world,

“the modern world,”

“modernity,”

“the Anthropocene,”

I ask you to imagine Earth’s surface
being a golf course of global proportions

with oceans being
oversized water features.

I don’t play golf,
but the analogy works for me.

Everything everywhere
is the result of human choices,

whether conversions of places
to better suit our needs

or the set-asides of places
for various reasons.

The intensity of transformation

falls on a continuum
on local golf courses,

from the holes in the sod
to the smooth greens

to the long fairways

to the uncut rough
and the forested out-of-bounds,

and this entire patchwork of places
lies below a human tweaked atmosphere.

On an actual rather than
golf-course-imagined Anthropocene Earth,

the intensity of transformation on land

falls on a continuum
from urban downtowns to suburbs

to ruburbia

to remote wildlands;

and on the sea,
it falls from fortified beaches

to dredged channels

to anoxic dead zones.

Both patchworks of places also lie
beneath a human-tweaked atmosphere.

Make no mistake -

geological modernity has arrived.

Its name is the Anthropocene.

After a day at work

spent thinking and teaching
about the global Earth system

at the university,

I walk back home through the woods.

During my return trip,

I find it easier to see
these abandoned pastures,

the livestock pond, the cellar hole,
and the stone walls

for what they are -

fossil evidence of the epoch
before modernity.

Perhaps in some distant future,

a post-human intelligence

will discover the ruins and residues
of our Anthropocene epoch

embedded in yet unnamed strata.

If and when that happens,

modernity will need a new name.

Thank you.