Question about Sustainability

[Nox]

What do you think is the maximum population that can sustainably populate the earth?

I mean it in terms of, how many people can live in the planet and still have enough food/resources to provide for everyone whilst being environmentally sustainable

[Metacomet]

To what level of living?

10 billion living like current Americans/Canadians/Australians?

Probably not. Not unless we discover some awesome new fusion electricity and space mining.

With renewable energy, electric cars (lets face it, transport is necessary) more public transit, greener cities, more vegetarian/veganism?

I'd say 10 billion is doable.

[ÑóẊîöʼn]

It also depends on the general level of technology. If I remember correctly the maximum sustainable Earthly population of hunter-gatherers is under a billion, perhaps significantly so.

Personally, I think any more than 20 billion people is going to feel crowded, even with the equivalent of a second Industrial Revolution happening along the way.

Regardless of how big Earth's population is going to get, it is still a good idea for us to expand our resource base beyond the confines of this single planet, as well as industrialise Earth's orbit.

[Dr Mindbender]

What NoXion says. The question should not be ''how many people can the earth currently support'' as this is a distraction. The question should be what economic and distributional mode can maximise the health and happiness of as many people as possible. In that context capitalism is not fit for purpose.

[agnixie]

It also depends on the general level of technology. If I remember correctly the maximum sustainable Earthly population of hunter-gatherers is under a billion, perhaps significantly so.

Personally, I think any more than 20 billion people is going to feel crowded, even with the equivalent of a second Industrial Revolution happening along the way.

Regardless of how big Earth's population is going to get, it is still a good idea for us to expand our resource base beyond the confines of this single planet, as well as industrialise Earth's orbit.

To be fair, demographic projections are constantly having to be revised because they keep assuming trends that, in the end, are either wrong or taken too long term. It's unlikely that Earth will reach 20 billion within 3 or so centuries.

One of my teachers in HS argued that some agricultural methods applied worldwide, rather than exporting midwest american monoculture (and rather than the horribly wasteful slash and burn practiced by workers and landlords in regions like the amazon), could probably boost the carrying capacity of earth well above 20 billions, but energy would be the main problem until we found something that can replace oil entirely (safe nuclear, fusion, hydrogen fuel cells, renewables, etc)

[ÑóẊîöʼn]

To be fair, demographic projections are constantly having to be revised because they keep assuming trends that, in the end, are either wrong or taken too long term. It's unlikely that Earth will reach 20 billion within 3 or so centuries.

I wasn't making any predictions, I was merely passing a personal judgement as to what I would consider a "crowded" Earth - even if we compactify our cities and localise our agriculture, while moving the rest of our industrial expansion off the surface of the Earth, 20 billion people and their supporting infrastructure are still going to take up a lot of physical surface area, and I think any more would put too much pressure on the wild spaces.

Having said that though, I also think we should be spreading out as well as up - as life support technology improves, so does our ability to colonise the less habitable portions of the Earth. Such places could be the Antarctic, the oceans (surface or subsurface), deep underground or even in the upper atmosphere.

Compared to the kind of places where cities have typically been established, those areas are relatively lifeless, so there are fewer concerns about damaging or displacing any local wildlife, but also easier to colonise than other planetary bodies, while at the same time giving us the challenges and experiences we need to make that leap into the great dark.


One of my teachers in HS argued that some agricultural methods applied worldwide, rather than exporting midwest american monoculture (and rather than the horribly wasteful slash and burn practiced by workers and landlords in regions like the amazon), could probably boost the carrying capacity of earth well above 20 billions, but energy would be the main problem until we found something that can replace oil entirely (safe nuclear, fusion, hydrogen fuel cells, renewables, etc)

I know that farming methods such as vertical farming can be adapted to pretty much any local conditions, but I'm not sure if that was the sort of thing your teacher was talking about.

[ianz]

You'll need to define "sustainable" a little better, no life on Earth is sustainable (if for no other reason than the heat death of the universe). What time period are you trying to achieve sustainability over? I'm not convinced that humans are able to create organizational structures that have any type of long term (let's say 1000 years) sustainable social institutions (history would support this)

[alphshuffel]

It is very ambigiuos question. This is because, it is much difficult to estimate. We can not judge the food for people on the earth. When there was half strength of the people than now, living, they have also food for them selves and now, they also have getting food still.

[Zav]

I'd say about 5 billion people with current standards of living (for about a century or so), but I wouldn't want to live on such a crowded planet. I disagree with the technology-worshipping in this thread. It's as fallacious as Primitivism. There aren't the resources to colonise the solar system beyond Mars, and certainly not to the level that Earth is populated. The fact that we cannot manage one planet is not an excuse to seek a second. The amount of energy needed to terraform the moon, never mind Mars is tremendous, and ultimately would be pointless. The moon is basically one big rock. There aren't many usable ores that we know of. Peak Oil will be reached in a few decades, so from where shall the energy required for hundreds of shuttle launches come? From renewable resources? I think not. We consume more energy at present in fossil fuels than the sun provides, so how can we expect to sustain our way of life with more people than we already have on a rock where the only energy comes from the sun? We simply can't. Even with technology at perfect efficiency, energy cannot be created from nothing. If the 7 billion people already here want to not die from lack of resources (I mean their posterity), they'll have to become Vegans, live locally, and all be Communists, and that's that.

[ÑóẊîöʼn]

I'd say about 5 billion people with current standards of living (for about a century or so), but I wouldn't want to live on such a crowded planet. I disagree with the technology-worshipping in this thread.

Pointing out the self-evident power of technology is "worshipping" it now?


It's as fallacious as Primitivism. There aren't the resources to colonise the solar system beyond Mars,

News to me. What's missing?


and certainly not to the level that Earth is populated.

That's not necessary. What is necessary is that we get to the business of making sure that whatever presence we have in space relies on Earth as little as possible.



The fact that we cannot manage one planet is not an excuse to seek a second.

That's not why I advocate extraterrestrial colonisation.


The amount of energy needed to terraform the moon, never mind Mars is tremendous, and ultimately would be pointless.

The energy requirements are large compared to what we are currently used to, but what of it?

What's so pointless about a planet with a breathable atmosphere?

Besides, ultimately everything is pointless, because the universe has no reason for existing. But that's no reason not to try and ensure our survival.


The moon is basically one big rock. There aren't many usable ores that we know of.

What about the oxygen, aluminium, titanium, water (http://news.bbc.co.uk/1/hi/8359744.stm), and iron in the form of oxides? Don't those count?

Also, the Moon is more than just "one big rock" - it is a large spherical body with it's own unique geological history and a layered, differentiated internal structure that suggests an active past.


Peak Oil will be reached in a few decades, so from where shall the energy required for hundreds of shuttle launches come?

First of all, the Shuttle is retired now, so whatever ends up lifting stuff into orbit in the future, it won't be that. Secondly, you don't have to spend oodles of energy lifting a weedy chemical rocket with a tiny cargo into orbit. We built and tested nuclear rocket engines back in the 60s, and we're getting better at producing ever longer lengths of carbon nanotube, which are reckoned to be strong enough to construct a space elevator (http://en.wikipedia.org/wiki/Space_elevator).


From renewable resources? I think not. We consume more energy at present in fossil fuels than the sun provides,

[citation needed]


so how can we expect to sustain our way of life with more people than we already have on a rock where the only energy comes from the sun?

That's not true. The energy from uranium and others has nothing to do with the Sun.


We simply can't. Even with technology at perfect efficiency, energy cannot be created from nothing. If the 7 billion people already here want to not die from lack of resources (I mean their posterity), they'll have to become Vegans, live locally, and all be Communists, and that's that.

Please tell me you are joking.

[UnknownPerson]

I have a related question:
Does some sustainability level imply that with such a population level resources will re-generate fast enough not to deplete?