One billion, one continent
--------------------------

In the online circles I frequent, I bump into the notion of
"solarpunk" primarily in the form of a label applied to things
actual people are actually doing, a kind of practice.  But it's
"supposed" to be a genre of fiction, and when I first encountered
the term, around ten years ago now (and, yes, for the record, when
I chose the handle "solderpunk", I did kind of like that there
was a subtle nod to solarpunk in there, even though at the time
I wasn't anywhere near as focused on sustainability stuff as I am
now), there didn't seem to be any notion of it as anything *other*
than a genre of fiction.  It was a strange kind of "vapourgenre",
I remember discovering it and feeling like it was really strange
that there seemed to more words written about what solarpunk was
than there were words written in the total sum of actual solarpunk
literature, unless you counted stuff which had been retroactively
labelled solarpunk, stuff written years before the label existed.
I suppose this has probably changed quite a bit in the decade
since, I'm vaguely aware that Tomasino has a solarpunk writing
prompt podcast, which I ought to check out some time if I can ever
overcome my innate aversion to podcasts.

Anyway, the single defining characteristic of solarpunk as a genre
is optimism.  And to be honest, this never sat right with me, not
from day one, even though I'm about ten times more pessimistic these
days than I was ten years ago.  It wasn't that I was opposed to
optimism in principle, and in fact I never have been, even though
I realise it sure must not seem like it judging by my writing.
What I never liked was that it felt a little forced.  The first two
points in the "Solarpunk Manifesto"[1] are, one, "we are solarpunks
because optimism has been taken away from us and we are trying to
take it back", and, two, "we are solarpunks because the only other
options are denial or despair".  The very first time I read these
points, I was immediately reminded of those people who proclaim
that they believe in an afterlife "because it's too depressing"
to imagine that this life is all we get; optimism as a kind of
wilful self-deception.  That's harsh, perhaps, on solarpunks and
afterlifers alike.  Anything's preferable to a life of despair,
I can't argue with that.  Nevertheless, this seemingly naive
"optimism by fiat" is the reason that, even though I have used
"solarpunk" pragmatically as a label to find and be found by the
kind of people that I want to talk to about these issues, I have
never really thrown myself behind the idea/movement, and have never
actually publically self-identified as "a solarpunk".

At the same time, I have become entirely disenchanted with the
mainstream science fiction take where we circumvent the sheer
finitude of Earth by instead expanding out into space, mining the
asteroids, terraforming Mars, etc., etc.  It's not that I doubt any
of it is technically possibly in principle.  It's not because I'm
sceptical (even though I deeply am) that any of this stuff could be
done well enough and quickly enough to avoid serious environmental
unpleasantness here on Earth.  It's because I've come to realise
that, while it makes for great reading at the right scale, if
you zoom out and play that tape on fast forward long enough, it's
actually very uninspiring and unsatisfying.  The question is simply:
where does it end?  Suppose we do "go full space", and increase
our access to material resources and energy by, say, six orders
of magnitude.  Suppose we even manage to avoid "going full Jevons",
and we respond to this huge increase by only increasing our appetite
for those resources by, say, three orders of magnitude, leaving a
net three orders gain.	It only took us a few hundred years from
the start of industrialism to run into really serious problems
here on Earth.	What if it only takes us a few hundred thousand
years to exhaust the solar system?  That's a long time, but it's
not ridiculously long, it's about as long as humans have existed on
Earth so far.  Okay, maybe in a few hundred thousand years we have
a fleet of generation ships with nuclear propulsion systems heading
out to nearby stars, and we can reap another few orders of magnitude
more stuff.  But that won't last forever, either.  Maybe it will last
for millions of years.	But by the point we've reached other stars,
we no longer have a hard 5 billion year deadline on existence in
the form of our Sun going Red Giant.  Do we just keep doing this
forever, until the heat death of the universe?	Is this who we are?
Man, the Expander?  Man, the Consumer?	Man, the Depleter?  Is the
reward for becoming an immortal multi-planetary species just a
never ending treadmill session, sprinting from crisis to crisis,
living forever on a knife edge between running out of resources
and being buried in our own waste?

I am deeply unmoved by that vision of the future!

But lately I've been wondering: what happens if we take that
vision of the future and flip it around entirely?  What if we
launch ourselves not into a great act of expansion, but into one of
*contraction*, and do it with exactly the same level of enthusiasm
and sense of purpose and grandness of scale and hand-waving disregard
for questions of financial or political practicality?  I, for one,
have never read anything like that before.  That's not to say it
doesn't exist, of course.  If you know of any, please do share!
But once I started thinking along those lines, I came up with
a hypothetical future scenario that I just couldn't put down.
Turning this idea over in my head has been an awful lot of fun,
and to my surprise, it ended up with me feeling more optimistic
about sustainability than I have in many, years.  Naturally, I'm
keen to share!	First, some disclaimers, and an acknowledgement:

1. This post is not an actual work of inspirational science
fiction as the solarpunk movement calls for.  It's a world-building
exercise, and a quick sketch exercise at that.	The result is a world
within which I think some compelling actual works of fiction could
definitely be written, and if that's something you feel like doing,
please feel extremely free!  I'd love to read the result.  But I'm
certainly not aspiring to that myself.	There are no characters
in this post, there's no plot, it's just a vision, a world, a
big picture.  You know, the lazy, easy part of writing scifi.

2. This post is not a blueprint!  It will not take long to come
up with lots of practical questions like "who pays for this?" and
"is this even possible without an authoritarian world government?".
I do not have answers to those questions.  I don't even pretend to.
It's entirely possible that there is no practical pathway from
today's real world to the world I'm about to describe.	But you
can ask just as many questions like that of most traditional space
expansionist science fiction, too.  Unanswered questions like that
don't necessarily detract from the enjoyability of the vision and,
crucially, they don't detract from its ability to change mindsets
and inspire actions which *are* feasible in the real world.
Unrealisable hand-waving can still win hearts and minds.

3. This post is not my personal vision of a Utopian future, and
it won't be perceived as such by anybody else who yearns after a
Waldeneseque cabin life of simple solitude.  I'm not saying I want
to live in this world, I'm not saying we should get out of bed
tomorrow and actively try to make this world happen.  It's more
like...if you want to cling to the idea of high-tech industrial
civilisation, if you want to sketch a world where everybody lives
a life that is vaguely recognisable and not totally unpalatable
from the perspective of the early 21st century "Global North"
lifestyle, if you're allergic to primitivism, but you also realise
the magnitude of just how big a mess we are in and and what kind
of corrective action is required, if you want to do more than pay
mere lip service to the notion of "planetary limits", if you have
accepted the idea that "the Earth is not for us"[2] right into the
core of your worldview, well, then, if you want to combine all those
things into a consistent vision, I think this is the direction you
need to start thinking in.  I haven't spent much time thinking in
this direction, and I don't think many people have.  I just wanna
get that ball rolling, and framing it in a big, expansive science
fiction vision is a fun and easy way to kickstart that ball, and
it lets me play fast and loose with details (although I have really
tried to keep this grounded in some semblance of reality).

4. I first started thinking along these directions during, and
in response to, reading Stewart Brand's "Whole Earth Discipline"
last year.  I don't necessarily think Brand would endorse this vision
at all; he's bigger on technological solutionism than I am and far
less concerned with issues of population and carrying capacity.
And the core notion of civilisational contraction doesn't appear in
the book at all, at least I don't recall it.  But Brand *is* big on
urbanism, convincingly so, and I've leaned on that idea pretty hard.

Okay, with all that out of the way, let's get stuck into some
hardcore speculative "degrowthpunk" (hey, the more microgenres the
merrier, right?).

The essential thrust of this world is simple, and you've probably
already got it from the title: humanity has voluntarily reduced
its population to around one billion people (cf about 8 billion
at time of writing, projected to peak at around 11 billion by the
year 2100) and has not only abandoned the aspiration of becoming a
multi-planetary species, but has even voluntarily ceded its current
status of being a whole-planet species.  One and only one continent
on Earth is designated as being "for humans".  All the others are
treated roughly like Antarctica is treated today; small numbers of
humans might spend short periods of time there in the interests
of science, but this is a careful, minimal presence.  There are
no farms, no mines, no factories, no dumps, military activity is
prohibited by treaty, nobody is born there and if everything goes
according to plan nobody dies there.  If what needs doing there can
be done with satellites or drones instead of people, all the better!

(11 billion peak population from the Wikipedia article: "Projections
of population growth[3])

(I won't say anything in this sketch about *which* continent is
"ours", but it would be a fascinating and difficult choice to make!)

A quick reality check, because most people, myself included,
have very little intuition about numbers at these scales: a total
human population of one billion is not in any sense absurdly small.
The last time there were that few of us was around was as recently
as 1800.  We'd circumnavigated the globe, we'd discovered calculus,
we'd invented the printing press, the industrial revolution was
just getting started, empires and wars were old hat.  That's not
supposed to be "humanity's greatest hits", empires are wars are bad,
and I didn't even touch on philosophy or art.  My point is that one
billion people is absolutely enough for large groups of people to
unite together in common purpose and organise themselves enough to
get techno-social things done on a big scale.  Not just as a one
time thing, it's enough for multiple such large groups to be doing
their own things in parallel, with distinct cultures, languages,
politics, philosophies, religions.  It's not in any sense a "small
world", it can be big and active and diverse.  It's not too few to be
worthwhile, not even close.  And cramming that many people into one
continent is not actually a matter of cramming at all.	There are
4.6 billion people in Asia right now, 1.4 billion in Africa and if
you count North and South America as a single continent, just over
1 billion there, too.  So in fact this world can be realised with
a lower mean population density than some continents have today.
I think the basic premise passes the laugh test.

(Per-continent populations from Wikipedia article: "World
population"[4])

The "greenness" of the reduced population is self-evident.
Humanity's total ecological footprint is the number of people
multiplied by the mean individual footprint.  You can reduce it by
reducing either of these things.  The more you reduce the number of
people, the less you have to reduce the individual footprint to hit a
certain target implied by planetary limits.  Reducing the individual
footprint is more or less equivalent to reducing what most people
would think of as "standard as living".  If you want to maximise
standard of living without the total footprint exceeding planetary
limits, you minimise population.  A sustainable human civilisation of
one billion people can enjoy roughly ten times the standard of living
of a sustainable human civilisation of 10 billion if the comparison
is done on the same timescale.	It's really just that simple.
I mean, it's conceptually simple to see why this is necessary,
actually achieving and maintaining a roughly tenfold decrease in
population without mass death or repression of individual liberties
seems extremely difficult to me, but hey, we're hand waving here.
What's the big deal about the one continent thing, though?  Well,
there's a lot.

Right now, as you read this, there are around ten thousand planes
in the air (11,847 to be precise as I write this), almost all of
them burning fossil fuels and releasing carbon dioxide into the
atmosphere.  Most of them are moving people around, but some are
moving stuff.  There are also thousands of ships in the sea, there
are almost six thousand container ships alone, and almost all of
those burn fossil fuels too, in addition to regularly discharging
all kinds of nasty waste products into the sea because they can
get away with it.  Most of them are moving stuff around, a lot
of it precisely those fossil fuels, but some are moving people.
These are both huge industries with huge footprints and the
conventional sustainability wisdom is that those industries need to
be "greened up" hard and fast, by e.g. electrifying planes and ships.
But if the entirety of the human enterprise is on one continent,
then there is simply no need to ever move people or stuff across
oceans in either planes or ships.  You can move everything by rail,
which is both fundamentally less energy intensive and also easier
to do with green electricity because railways can be built near
power grids, which don't exist in the middle of the ocean or in
the middle of the sky.	Maybe we can't do away with every single
airplane and every single ship, but by going mono-continental we
can deprecate over 90% of both these industries, which will yield
even bigger savings than electrifying them would, while freeing up
R&D resources for other problems.

(Total aircraft count at time of writing from FlightAware[5])

We don't just move stuff all over the Earth at great energetic
cost.  We move information, too, these days mostly digital data.
When it comes to fast and reliable non-stop communication from
one side of the planet to the other, there are two games in town.
One is satellites.  There are about 4,500 of these orbiting above
you right now, used for a variety of purposes, but about 60% of them
are communication satellites (admittedly not all of those commsats
have the primary purpose of relaying signals over the horizon).
The other is a network of cables lying on the ocean floor.  These
things are both marvels of engineering and they work well, but they
are not easy, either.  The total footprint of this infrastructure,
the manufacturing, testing, launching/laying, constant monitoring,
maintenance, the burdens of responsible end-of-lifing so we're not
filling LEO with dangerous high speed junk or permanently abandoning
high purity finite resources on the ocean floor, is substantial.
And if we all live on one continent, it all becomes obsolete.
Underground cable networks are tremendously easier and cheaper
to install, inspect, and maintain and can achieve much longer
lifetimes than underwater cables.  Ditto for point-to-point
radio links between large antenna towers compared to satellites.
High speed, low latency, 24/7 connectivity between any arbitrary
pair of human beings, possibly the defining feature of modern life,
might just actually be sustainable if we're all on a single landmass.

(Satellite counts from an article by DEWEsoft[6]

Modern globalised industry has a nasty aspect of inequality to it:
the most dangerous and most polluting activity happens in the poorest
parts of the world, out of sight and out of mind of the richest
parts, whose lifestyle's disproportionately contribute to the demand
for the energy and resources as well as the waste that give rise to
the need for danger and the pollution in the first place.  If the
entirety of human enterprise is confined to a single continent,
this cannot happen to anything like the same extent.  We would all
share the same backyard.  When everybody is downwind or downstream
from somebody else, when you can take a train and see the world's
largest pile of trash with your own eyes, that provides a powerful
motivator to make every industrial process as green as it can be,
and to outright abandon those which can't be made green enough.

But all of the benefits above are not even close the real core virtue
of becoming one billion on one continent.  They are benefits from
the perspective of technoindustrial society.  The real benefits are
ecological, they are benefits from the perspective of the planet
itself.  The real core virtue is that by confining ourselves to
a single continent, we are necessarily giving all the others back
to nature.

I'm not just talking about the psychological or spiritual benefits
that many - but not everybody - will reap from seeing this as a
species-level act of atonement, a peace offering to Gaia, reparations
for ecocide, a glimmer of hope for all those species pushed not quite
to the point of extinction but darn close to it, although I don't
think those benefits ought to be sniffed at.  Instead I'm talking
about the fact that large, complex, diverse natural ecosystems
are in fact planetary infrastructure, infrastructure which does
an excellent job of managing and maintaining itself at zero cost
to us if we simply leave it alone.  That's not to say that mother
Nature couldn't use a helping hand in rewilding multiple continents
as quickly as possible under the adverse conditions we've created.
She certainly could.  This story forks in two here, you can follow
the route that appeals to your convictions the most.  Down one
thread, we are entirely hands off about the rewilding after an
initial cleanup (more on that soon), down the one we use our
understand of ecology and Earth sciences to take an active role,
but either way the threads rejoin after a century or two when, in the
active role version, we say "okay, you're off to a good start, we'll
leave you alone now, watching your progress lovingly from space"
(22% of satellites are for Earth observation, and it's certainly
worth keeping those birds flying).

The planetary infrastructure we need the most desperately is
several continents worth of forest, grassland and wetlands, which
will collectively be able to sequester huge amounts of carbon from
the atmosphere.  Our ongoing emissions ought to be reduced so much
by the drastic downscaling and the confinement of our activities to
a small area that several continents of wild biota can not only
capture it but start working on our several century backlog,
too, gradually reducing the total amount in the atmosphere.
"Planting trees to save the planet" doesn't really get a lot
of attention as a serious solution to climate change, it comes
across as terribly naive.  But most of the back-of-an-envelope
calculations that make it look like a non-starter come out that way
because they framed within the status quo of global civilisation.
The problem with that is there's just not enough free space to plant
the prodigious quantities of trees required, because we've used so
much of it up.	Close to half the Earth's habitable land is used
for agriculture[7].  The second most common form of land use after
agriculture is already forests.  The only way to get more room to
grow more forests without cutting existing forests down is to grow
less food (or at least to grow more crops and less meat and dairy).
Even if we could find room to plant trees, we tend to have a hard
time stopping ourselves cutting them down and burning them, which
just releases the carbon again.  But both of those problems are gone
in this world; there are multiple continents entirely free from both
agriculture and from logging.  Forests also get a bad rap as carbon
sinks because when they burn in wildfires, they one again release
the carbon they've stored.  But multiple continents worth of forest
are not going to all burn down at once, and natural forest ecosystems
are a lot more resistant to wildfires - some even depend upon them! -
than artificial monoculture forests planted and managed by humans.

Now, I'm not suggesting we just up and leave most of the continents
as they are without a little tidying up first.	It's not that I think
nature would particularly struggle to clean up after us by herself.
It just makes no sense to leave behind the huge quantities of useful
finite resources that we've gotten ourselves into this mess by
extracting and refining.  That stuff is precious, and great damage
has been wrought in producing it, so we shouldn't let it go to waste.
So a big part of the story of how this world comes to be is a huge,
planet-spanning, multi-generational salvage project, in which we at
least partially disassemble the trappings of human civilisation on
all the continents but one.  There's really no prospect of us leaving
the other continents in pristine condition, no trace left behind,
and there's also no need for it either: again, mother nature will
not struggle to retake everything in time, reducing our legacy
to dust.  And at some point we'll hit diminishing returns, with
regard to how much energy it takes to transport and recycle stuff.
But at the absolute least we must harvest all the low hanging fruit,
especially all the easily salvaged steel, aluminium and copper.
So we'll rip up all the railways, all the power grids, all the
phone networks.  High tech infrastructure which can be redeployed on
the human continent should be disassembled and taken with us, too;
countless kilometres of fibre optics, entire solar and wind farms.
And our monuments shall not be spared either!  If we haven't chosen
North America as the human continent, then we'll tear down the Golden
Gate Bridge and the Statue of Liberty.	If we haven't chosen Europe,
we'll scrap the Eiffel Tower.  All those giant Buddhas,  the Sydney
Harbour Bridge, anything that's just one big single solid thing
comprised mostly of structural grade metal is just a big lump of raw
material for the taking which we can't afford to leave behind out
of sentiment.  The final voyages of all those cargo planes and cargo
ships that we won't need anymore after civilisation has contracted
to one continent will be used to lug the precious material resources
salvaged from all the other continents back to ours.  Once that's
finished, the planes and ships themselves will be scrapped, too!
We will literally build the new world out of the corpses of the old.
There will still be plenty of recognisable relics left behind which
don't make energetic sense to move.  We can watch them decay over
centuries from orbit, or from scientific reconnaissance drones, to
remember the old world, and meditate on the nature of impermanence.

What will we build, on one our one chosen continent, with the
collective material haul of the entire rest of the globe?

Cities.  Really big cities.

The ten most populated "cities proper" on Earth have between 32
million people (Chongqing) and 13.5 million people (Tokyo).  Let's
take 20 million as a nice round figure, just a few less than Beijing.
One billion people fit in 50 cities that size.	Those 50 megacities
are the new "countries" of this world.	The return of the city state!
The population densities of those ten largest cities get as high
as 11,000 people per square kilometre (Delhi), but let's shoot for
something more like 4,000, about what Shanghai has.  That's higher
than some other big cities, but it's less than Delhi (a lot less!) or
Tokyo, so it's not an extreme density.	A city of 20 million people
with a density of 4,000 people per square kilometre takes up about
5,000 square kilometres.  50 cities that size take up about 250,000
square kilometres.  That's not even 1% of the land area of Africa or
Asia (of course, it's a much higher percentage of the non-desert,
non-mountain areas of those continents, but it's less than 1% of
the whole planet's habitable land area, according to the source
I used above for agricultural land use).  So the vast majority of
our continent is free once we're packed into the megacities - free
for agriculture, for huge solar and wind power farms, for mines and
factories and other icky things you don't want inside the cities.
Not that we should aspire to use the entire continent we have if we
don't need to.	While the continents which aren't ours are treated
roughly like we treat Antarctica today, whatever is left of the
continent which *is* ours, once we've built the bare minimum of
stuff we need to keep ourselves alive, is treated roughly like we
treat national parks today.  Some parts are very strictly protected,
but there are also places you can go to touch grass and hug trees and
camp, so that you don't go completely nuts from living in a megacity.

(All population and density stats from Wikipedia article: "List of
largest cities"[8])

Why are we living in megacities, instead of countless tiny
decentralised eco-villages?  Because density is green.	If the
places you learn, work, play, eat and heal are all within reasonable
walking or cycling distance of the place you live, then you are
far less reliant on mechanised transport.  It's well documented
that people who live in the countryside are more likely to own
cars than people who live in the city, and they drive further, too.
We need a lot less cars in the world.  Road transport actually does
a lot more damage than air transport and sea transport combined.
Electric cars are better than fossil cars, but no cars are better
than both.  Urban density makes public transit viable.	This all
goes for stuff as well as people: everything ought to be produced
as close to possible as where it will be consumed.  When stuff has
to be sent from far away, sending vast quantities of it hyper dense
population centres where it can then be distributed by foot or bike
is better than driving trucks to countless countryside supermarkets.
It's exactly the same principle that kicked this whole story off:
everybody on one continent is better than everybody spread out
over a planet, and everybody packed into cities is better than
everybody spread out over vast countrysides.  The closer together
everyone and everything is, the less distance you have to move
people and things, which reduces energy requirements, which is
the name of the game.  Cities certainly aren't without problems.
For one, population density increases susceptibility to pandemics,
as nobody needs reminding.  And a totally self-sustaining city is
not a plausible thing.	There will need to be an "outside", where
we have farms, mines, etc.  There will be people working in those
places, which means it makes sense for people to be living in those
places.  Maybe permanently, maybe people will rotate out from the
city to the countryside for a kind of one year civic service stint,
maybe a mix of both.  But the vast majority of people will spend
the vast majority of their time in the city.  This aspect of this
world is just the logical conclusion of the route the real world
is currently on.  The urban to rural population split is already
past 80:20 in the US[9], and is close to 60:40 globally[10], with
the rest of the world very keen to catch up.  Some souls, it's true,
will lament this, and they will yearn for quieter, wilder lives.
They will probably attempt to escape the megacities and live wild
and free illegally in the "national park zone".  They will make
for colourful characters in fascinating side-stories (especially
if they attempt desperate Kontiki voyages to get even further away,
and return to depopulated continents...).

That's pretty much all I've got.  The overall picture is actually
basically not much more than an inversion of the standard scifi
environmental dystopia trope.  You know the one.  The earth has
been rendered uninhabitable by nuclear winter or alien disease or
grey goo, or whatever, and a small humanity flourishes inside a big
shiny geodesic dome, where the power of advanced technoindustrial
civilisation protects them from the horrors of the unlivable world
outside.  The solarpunk/degrowthpunk version of this is that the
whole Earth is shiny and green and verdant and bursting with life,
and the reason is that we have protected *it* from *ourselves*,
not the other way around, and we've done it by squeezing all the
damage that advanced technoindustrial civilisation unavoidably wreaks
into the smallest possible space.  The domes are no longer strictly
necessary, but if you want to picture 50 giant dome cities, I won't
be mad.  Domes or none, picture the Earth from space, viewed from the
night side.  It's completely dark.  And then, slowly, our continent
rotates into view.  There's humanity!  An Earthbound constellation,
50 bright points of light, and nothing more.

The best part of all, at least for me, is that this process does
not need to stop here!	When you zoom out and play *this* tape on
fast forward, it's not a treadmill of endless expansion, endless
consumption, endless waste.  It's a humanity that never stops making
itself smaller and leaner.  It's a delightful inversion of the
absurd promise of ephemeralisation.  Instead of doing more and more
with less and less until eventually you're doing everything with
nothing, you do less and less with less and less until eventually
you are doing nothing at all with anything.  This might actually be
the one and only way to resolve the tension between a finite Earth
and a desire to sustain human civilisation for as long as possible.
Sustainability via Zeno's paradox!  You burn through half what the
planet can give in a few hundred years.  Then you burn through half
of what is left over the new few thousand years, then half of what's
left after that over the next few tens of thousands of years, and
so, and so on.	Each big decrease in the rate of consumption gets
harder and harder: science and technology will carry us some of the
way, but eventually everything becomes as efficient as the basic
constraints of physical reality and law allows, then the only way
forward is to decrease the population yet further, or decrease our
levels of material comfort, or both.  But as the steps get harder
and harder, the available time frame left to make them gets longer
and longer, too.  We can wean ourselves off each level of excess
arbitrarily slowly.

I *am* deeply moved by that vision of the future!

Mathematically, you can epsilon-delta your way out to infinity
with this approach, stretching even the smallest planet's finite
resources out until the heat death of the universe.  In reality,
technoindustrial civilisation surely requires a minimum population to
sustain it, and it can only offer people a certain minimum standard
of living before it stops being an attractive alternative to hunting
and gathering in the first place.  There's definitely a floor to
this process.  I don't think anybody has any well-informed idea
how low that floor is or how long we might be about spin out our
descent to it.	For five billion years, until the sun goes Red Giant?
Probably not.  Which is kind of a shame, because let's face it, no
goal for the species could ever possibly be more literally solarpunk
than to aspire to hang on for just long enough to be willingly
consumed by the sun!  But there's probably some much shorter time
limit to Earth's habitability than that anyway, the climate flips
between greenhouse and icehouse equilibria even absent our influence,
and maybe, just maybe, we can spin this charade out until then.

I'm perfectly content with the idea of humanity being a single-planet
civilisation which aspires with all its heart and mind to die
a natural death at the hands of forces beyond our control,
as opposed to committing eco-murder-suicide in the vainglorious
pursuit of immortality.  I say that with conviction and without the
least trace of misanthropy.  Long periods of time pondering a very
literal definition of "sustainability", where the goal is simply to
keep going forever, has made me realise how utterly unmotivated that
goal actually is.  Maximising human happiness, or minimising human
suffering, or some clever utilitarian weighted combination of the
two, is not in any way, shape or form the same as maximising the
amount of time between when the first human was born and the last
human dies, or maximising the cumulative total of human-hours lived.
These things are in fact almost entirely unrelated.  They may
even be in opposition with one another.  So be it!  Let's seek
deep and fulfilling meaning for our existence in careful planetary
stewardship, not pointless, endless expansionism.

Heck, maybe everybody else in the universe has already figured this
angle out.  There's your solution to Fermi's paradox right there.

 [1] http://www.re-des.org/a-solarpunk-manifesto/
 [2] gopher://zaibatsu.circumlunar.space:70/0/~solderpunk/phlog/the-earth-is-not-for-us.txt
 [3] https://en.wikipedia.org/wiki/Projections_of_population_growth
 [4] https://en.wikipedia.org/wiki/World_population	
 [5] https://flightaware.com/live/
 [6] https://dewesoft.com/daq/every-satellite-orbiting-earth-and-who-owns-them
 [7] https://ourworldindata.org/land-use
 [8] https://en.wikipedia.org/wiki/List_of_largest_cities 
 [9] https://ourworldindata.org/grapher/urban-and-rural-populations-in-the-united-states
[10] https://ourworldindata.org/how-urban-is-the-world