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Copernicus
2010-Mar-10, 06:53 PM
If the population of humans grows at the rate of 0.7 percent per year, for the next 700 years, there will be 7 trillion humans on earth. The average area, available human occupancy, would be about the size of a twin bed. I think that there will be many armagedons inbetween to prevent this type of population. What do you think will happen?

cjl
2010-Mar-10, 07:00 PM
I think that there will neither be exponential growth, nor will there be armageddon. Instead, as with pretty much every population problem, the growth will flatten out and plateau, probably at somewhere around 10B people.

Argos
2010-Mar-10, 07:19 PM
Population growth percentages are useless for long-term predictions, IMO.

korjik
2010-Mar-10, 07:22 PM
I think that there will neither be exponential growth, nor will there be armageddon. Instead, as with pretty much every population problem, the growth will flatten out and plateau, probably at somewhere around 10B people.

Same for me, but at 'in around 2050'

rommel543
2010-Mar-10, 07:23 PM
Honestly IF mankind survives the couple of hundred years it would be surprising. If we don't get wiped out by a super germ of our own design then run-away global warming is going to destroy our food supplies.

eric_marsh
2010-Mar-11, 03:30 AM
The singularity will occur well before then. Perhaps as early as 203x something?

Cougar
2010-Mar-11, 03:43 AM
The singularity will occur well before then.

Someone will divide by zero?

Bluevision
2010-Mar-11, 03:46 AM
We're definitely gonna plateau before that, I'm guessing (hoping) at around 10 billion. That's enough for the Earth to sustain if we commit towards being green and as eco-friendly as possible. That means that after that, we can have a very steadily increasing population to send out into space gradually to colonize the Moon, Mars, Venus, Asteroid Belt, etc. etc. in very manageable, bite-sized chunks.
There's a whole host of things that I think are going to be radically different in this near future, but I just hope that we either naturally or artificially develop a way of humanely and easily maintain the population around 10 billion. Cause honestly, if we go to sustainable living and low-impact/space agriculture, we could house those 10 billion people and have much of the world looking like it always was before we came along. Or at least, that's my dream.

I think maybe our solar system could eventually house 1 trillion humans or around there, but that'd still be only like 10 billion on Earth, maybe 15 billion at the most on Mars and Venus. The majority would be Asteroid Belt and Trojan asteroids.

But if there was to be something to stop our pandemic growth (assuming we don't plateau,) I'd say Global Warming's our biggest threat. Either that, or a war brought on from a combination of Global Warming and diminishing space.

Atraveller
2010-Mar-11, 04:15 AM
But if there was to be something to stop our pandemic growth (assuming we don't plateau,) I'd say Global Warming's our biggest threat. Either that, or a war brought on from a combination of Global Warming and diminishing space.

I agree with this one - although I would prefer to call it climate change - because it is not the heat - but the humidity that will get us... :lol:

Seriously - I think serious weather events will become common place - and we will get used to news reports that 200,000 - or 500,000 people are dying from the effects of a super storm, or whole years of crops and animals being wiped out, or massive floods...

I'll bet the population crashes - and some time before the end of this century we see a huge drop in population...

The Backroad Astronomer
2010-Mar-11, 04:18 AM
I already think 6 billion is too many.

Provence
2010-Mar-11, 04:49 AM
I think maybe our solar system could eventually house 1 trillion humans or around there, but that'd still be only like 10 billion on Earth, maybe 15 billion at the most on Mars and Venus. The majority would be Asteroid Belt and Trojan asteroids.


I'd say Global Warming's our biggest threat.

That's going to be one pretty fierce case of global warming, if it makes living on earth harder than living on Venus, Mars, or asteroids.

SolusLupus
2010-Mar-11, 04:54 AM
All evidence points to birth rates going down, and soon to be surpassed by the death rate. This is usually correlated with technological strides and a move towards urbanization. However, many many countries are growing industrialized.

Trying to predict the rate of population growth for hundreds of years without factoring this demonstrates, to me, a great fallacy and ignorance towards trends.

Gillianren
2010-Mar-11, 06:09 AM
That's going to be one pretty fierce case of global warming, if it makes living on earth harder than living on Venus, Mars, or asteroids.

If it makes living on Earth that difficult before we have the technology to build those colonies (personally, I don't find colonizing Venus at all probable pretty much ever), yes.

Delvo
2010-Mar-11, 06:38 AM
There will be no wars to substantially reduce the population. It just isn't possible.

Global warming doesn't have that potential at all either.

What will reduce the population (if we don't do it voluntarily first by just not having so many babies and maybe not stretching our lives out so long) are the effects we're having on fresh water supplies and soil. There's no such thing as sustainable agriculture because any and all agriculture must increase erosion to at least some extent and reduce the soil's nutrient content with every harvest; that means that the only sustainable population level is the level that could have been supported by hunting & gathering. And using water from wells is also ultimately impossible to sustain because wells run dry sooner or later; that means that the only sustainable population level is the level that could have been supported by water from precipitation alone (including precipitation-fed bodies of surface water). And that includes not just water for drinking and cleaning, but also crop irrigation... which is the only thing making it possible to farm anything at all in, for example, most of the middle of North America. So when you picture the future population and food supply, picture it without any farming going on in regions like that.

HenrikOlsen
2010-Mar-11, 07:49 AM
... reduce the soil's nutrient content with every harvest;
Which is where fertilizer and crop rotation comes in.
Combined with Science! (http://www.youtube.com/watch?v=2IlHgbOWj4o) to prevent overloading the system so the nutrients are wasted by draining into surrounding waterways.


And using water from wells is also ultimately impossible to sustain because wells run dry sooner or later; ...
Depends on rate of use.
With the soil properties in Denmark, a common well made to spec is fed by precipitation that spent about 20 years draining down though the various layers.
If the rate of use is less than the max rate for that movement it won't run dry until the rain stops falling permanently.

But yes, longterm sustainable farming is likely impossible at the level farming is currently done, which would suggest a long term equilibrium of fewer people than we have now.

The absolute need for crop irrigation means the mid-US farming is sitting on the time bomb of soil salinization that's already starting to affect yields and likely will continue to do so in the future.

Provence
2010-Mar-11, 08:25 AM
If it makes living on Earth that difficult before we have the technology to build those colonies (personally, I don't find colonizing Venus at all probable pretty much ever), yes.

So you don't see Venus ever getting colonized, but you agree that it's easier to live there than on a globally warmed earth?

:confused:

Jens
2010-Mar-11, 09:38 AM
Someone will divide by zero?

Please don't do it! You might get us all killed rather than win us immortality. Division by zero is absolutely verboten.

Jens
2010-Mar-11, 09:41 AM
I already think 6 billion is too many.

We all think 6 billion is too many, as long as we are not among the too many. :)

Jens
2010-Mar-11, 09:45 AM
What will reduce the population (if we don't do it voluntarily first by just not having so many babies and maybe not stretching our lives out so long) are the effects we're having on fresh water supplies and soil.

I partly agree, but I think that there are heroic measures that can be taken to alleviate that to some extent. It is possible to remove salt from seawater using solar power, though yes, it's an extremely costly process. Soil also can be managed if it's done carefully. Otherwise, plants wouldn't grow in the wild.

Sententia
2010-Mar-11, 12:38 PM
Nobody can accurately predict the future, or what will become of our descendants. We can only guess, and assume natural disasters, plagues, and war will reduce populations. I doubt the human population will ever descend gradually as if it's like a "trend".

After the world really is united which I can see happening in the next 100 years, With the healthcare industry profiting trillions of dollars each year I won't be surprised if humans haveto pay in order to conceive children. Not allowing pregnancy's, but making it the states right to dictate weither you start a family or not and make payment plans according to how long your child will live for-- 65 years to 165 years. Something like this I can really see happening.

The number of humans on earth will never exceed 50-80 billion.. we just cannot sustain anywhere near that. Be thankful to be alive now, and not too late.. because you might not be able to get a piece of pie, unless it's made of mud.

rommel543
2010-Mar-11, 02:43 PM
I think some strategically placed asteroid impacts would alleviate much of the current over population and assist with the climate change at the same time.

Jens
2010-Mar-11, 03:18 PM
I think some strategically placed asteroid impacts would alleviate much of the current over population and assist with the climate change at the same time.

As long as you're willing to personally be at the impact site, go for it.

rommel543
2010-Mar-11, 03:22 PM
Well, if I had no choice to be in the blast area I would rather be ground 0 then 5 or 10 miles out. From a scientific point of view it would be interesting to watch it come down. The show would be over quickly, but interesting none the less.

Sententia
2010-Mar-11, 03:29 PM
I can imagine a strong solar flare from the sun wiping out the satellites, phones, etc.. that in itself would take years to get everything back on, and probably cause millions of deaths.. this could be a likely scenario in our lifetime

crosscountry
2010-Mar-11, 03:39 PM
water is a limiting resource. You think wars over oil were big.

Delvo
2010-Mar-11, 03:46 PM
Which is where fertilizer and crop rotation comes in.Rotation only addresses nitrogen. It does not-a-thing-at-all for any of the other elements. Fertilizers only exist to replace a few of those, mainly phosphorus and potassium. And a lot of what's in fertilizers gets run off before it ever integrates usefully into the soil. And it comes from mines, which not only means there's a lot of mining and shipping involved, but also means the supply is finite and shrinking.


Soil also can be managed if it's done carefully. Otherwise, plants wouldn't grow in the wild.I'm not sure what you mean here, because soil in the wild isn't managed. If you mean that wild ecosystems manage not to ruin their soil so farms should be able to avoid it too, then that's not taking into account some of the major differences between the two things. In the wild, plants and animals die and drop waste products and leaves and such right there in the same environments where they live, and it all gets decomposed right where it dropped, so the ions that came from the soil stay in the environment. With harvesting, they're taken away. (And harvesting and mechanical operations associated with farming also tend to expose the soil to more physical erosion.)

Also, even in wild ecosystems, some erosion and nutrient loss still happens whenever any dirt or organic matter ends up in flowing water and taken out to the ocean, so there's a net decrease in the land's ability to support life anyway unless new soil is produced to replace it (from volcanic fallout and the breakup of larger rocks brought to the surface at mountains). But at least in nature, the rate of loss of physical soil and/or its nutrient ions is slow enough that volcanic/tectonic replacement can usually roughly keep up... and even without those things happening, it still takes dozens of millions of years for real problems to come from it. (Look at Australia.)

rommel543
2010-Mar-11, 03:50 PM
Honestly I believe Gwynne Dyer's future of mankind. We're going to see massive weather disruptions causing food shortages globally. This will cause billions of refugees in search of food and spark military actions over remaining resources. More technologically advances countries like the US and Canada will be less affected but food shortages will occur here as well. We can already see this by the drought occurring in Australia. Areas that were used to grow grain for export to Asian counties are now desert like and abandoned. Since 2003 rain falls have been dismal if non-existent.

BUT on the upside, if we're able to survive whats coming I think that we will be far more environmentally conscious.

korjik
2010-Mar-11, 03:51 PM
water is a limiting resource. You think wars over oil were big.

You do realize that it actually falls from the sky, dont you?

If you add desalinization, then there is more water on Earth than the mass of Ceres.

korjik
2010-Mar-11, 03:54 PM
Most of y'all seem to live in a very depressing world.

All I have to say is that since lower Manhattan drowned in horse manure last century, I have paid all my attention to future demographics like this.

Sententia
2010-Mar-11, 04:01 PM
The United States has enough water, and desalination plants right now.. It's just those southern, east coast states that need it sometimes and even then it's not that drastically needed like 3rd world, or over populated country's do. Right now, strategically I'm more concerned about oil.. and helium, Earths resources that are not renewable that maybe depleted in our lifetimes. Water will always be a commodity to us.

rommel543
2010-Mar-11, 04:06 PM
You do realize that it actually falls from the sky, dont you?

It doesn't in drought areas and thats what will cause the wars.



If you add desalinization, then there is more water on Earth than the mass of Ceres.

Desalinization is expensive and viable for coastal regions. For inland areas we would need to build MASSIVE plants and major pipelines. Currently the world's largest plant only produces 217 million gallons per day. In 2005 the fresh water usage for the US alone was 410 billion gallons per day (resource (http://pubs.usgs.gov/fs/2009/3098/)), We would need thousands of plants all over both coasts to satisfy just the US's usage.

Sententia
2010-Mar-11, 04:10 PM
We would need thousands of plants all over both coasts to satisfy just the US's usage.

I would like a sea water pipeline .. It would solve alot of problems

HenrikOlsen
2010-Mar-11, 04:43 PM
water is a limiting resource. You think wars over oil were big.
One of the main not so often mentioned driving forces for the Israel/Palestine/other countries in that region thing is control of the Jordan river for irrigation.
Forget religion, water's already the real killer there.

crosscountry
2010-Mar-11, 04:58 PM
One of the main not so often mentioned driving forces for the Israel/Palestine/other countries in that region thing is control of the Jordan river for irrigation.
Forget religion, water's already the real killer there.

some people think that drinking water comes from the sky, but anyone with some knowledge of geology understands better than that. Most of the water consumed in the west is from too slowly replenishing aquifers. Las Vegas is just an example. Austin gets a lot of water from the aquifer.

At our current rate of growth Austin will use more water than our reservoirs can hold. That will deplete the aquifer, and we'll be pumping in salt water. Fortunately we can afford that, but other places cannot.

hhEb09'1
2010-Mar-11, 06:24 PM
If the population of humans grows at the rate of 0.7 percent per year, for the next 700 years, there will be 7 trillion humans on earth. The average area, available human occupancy, would be about the size of a twin bed. Just a question about your assumptions. :)

Land surface area of the earth (http://en.wikipedia.org/wiki/Earth) is about 150 million square kilometers. So, for 7 trillion people, that's about ten twin beds per person. I guess you're assuming 90% of the earth is uninhabitable, is that it?

What, did I screw up some math, again?

We could do a little better, after all. The John Hancock Center in Chicago only uses half its stories for apartments, about 700 condos. I don't think they're packed in there all that tight, they even have a swimming pool, right? Still, they're packed in about as tight as those 7 trillion, no?

Gillianren
2010-Mar-11, 06:38 PM
So you don't see Venus ever getting colonized, but you agree that it's easier to live there than on a globally warmed earth?

:confused:

Sigh.

No. If it becomes too difficult to live on Earth before we have the ability to build extraterrestrial colonies, I don't think we'll necessarily develop the technology until those problems are dealt with in one way or another. With Venus, we can't even send probes there without having them destroyed by the atmosphere.

Atraveller
2010-Mar-12, 12:36 AM
I already think 6 billion is too many.


As of 11 March 2010, the Earth's human population is estimated by the United States Census Bureau to be 6,807,700,000. - wiki

Estimates are we will reach 9 Billion around 2040... (30 years...)


Global water crisis
Grain storage facilities in Australia

Water deficits, which are already spurring heavy grain imports in numerous smaller countries,[24] may soon do the same in larger countries, such as China or India.[25] The water tables are falling in scores of countries (including Northern China, the US, and India) due to widespread overpumping using powerful diesel and electric pumps. Other countries affected include Pakistan, Afghanistan, and Iran. This will eventually lead to water scarcity and cutbacks in grain harvest. Even with the overpumping of its aquifers, China is developing a grain deficit.[26] When this happens, it will almost certainly drive grain prices upward. Most of the 3 billion people projected to be added worldwide by mid-century will be born in countries already experiencing water shortages. After China and India, there is a second tier of smaller countries with large water deficits—Afghanistan, Algeria, Egypt, Iran, Mexico, and Pakistan. Four of these already import a large share of their grain. Only Pakistan remains self-sufficient. But with a population expanding by 4 million a year, it will also likely soon turn to the world market for grain.[27][28]
[edit] Land degradation
See also: Land degradation and Desertification

Intensive farming often leads to a vicious cycle of exhaustion of soil fertility and decline of agricultural yields.[29] Approximately 40% of the world's agricultural land is seriously degraded.[30] In Africa, if current trends of soil degradation continue, the continent might be able to feed just 25% of its population by 2025, according to UNU's Ghana-based Institute for Natural Resources in Africa.[31]- wiki

Personal experience: How many people rely on the sea for their food? Yet I've seen Chinese Factory Trawlers (very impressive boats when you come up on them in the open ocean - and they take absolutely everything) Fishing the Humboldt Current off the coast of South America - 6000 miles from home. They have to go that far because the seas are becoming barren - the fish are gone, due to unsustainable fishing - like factory trawlers. How long before there is a seafood crisis?

If weather events don't destroy crops - through too much, or too little rain, soil degradation will lower outputs...

We need new technologies

Maha Vailo
2010-Mar-12, 01:16 AM
If there are problems with water, soil or fish, we will find ways to solve them.

With water, we can use it more wisely. Put up with dingy cars or slightly unwashed bodies for a change. Plant water-friendly landscaping. Be mindful about turning the tap on and off. Shower, Navy-style (or with a friend!).

Soil? Someone already metioned fertilizers and crop rotation, but what about precision agriculture?

As for fish and other seafood, why not farm the darn things, feeding them off the byproducts of already-existing food (or nonfoood!) industries?

What I'm trying to say is that the problems of the world are not insurmountable, as long as we put our minds to it. So stop complaining and make it so!

- Maha Vailo

Atraveller
2010-Mar-12, 01:43 AM
If there are problems with water, soil or fish, we will find ways to solve them.

What I'm trying to say is that the problems of the world are not insurmountable, as long as we put our minds to it. So stop complaining and make it so!

- Maha Vailo

That was what I was saying with my statement we need new technologies.

But the first step is we all have to agree there is a problem - and people are going to have to start making hard choices - and it doesn't seem we are capable of doing that yet, unless forced into it...

Population crash might be the forcing...

Bluevision
2010-Mar-12, 02:42 AM
That's going to be one pretty fierce case of global warming, if it makes living on earth harder than living on Venus, Mars, or asteroids.It's the fact that if we want Earth to continue through it's natural way of doing things, humans will have to have a very small impact, therefore lower population. Most experts agree that Earth can only sustainably support between 9 and 11 billion people, even with totally sustainable practices, with the high and low estimates being between 15 and 5. Venus and Mars, on the other hand, are worlds that can be built with human needs in mind, and don't have a specific biological requirement on us (yet.)
I'd think asteroids are an obvious possibility for their large amount of resources and very large surface area in total. And those areas, we really don't need to worry much at all about ecological needs, because the most we'll be doing is paraterraforming desolate balls of rock. There's plenty of possibilities for a sustainable economy out in the asteroids too, if you ask me. But to have Venus and Mars at 15 billion people would be thousands of years from now. Asteroids are most probably much further.


Rotation only addresses nitrogen. It does not-a-thing-at-all for any of the other elements. Fertilizers only exist to replace a few of those, mainly phosphorus and potassium. And a lot of what's in fertilizers gets run off before it ever integrates usefully into the soil. And it comes from mines, which not only means there's a lot of mining and shipping involved, but also means the supply is finite and shrinking.Yep, fertilizers are a totally unsustainable method of farming, sorry. In the long term, nitrogen fertilizers will actually vastly decrease soil productivity, and other methods of artificial fertilizer have similar effects. But, rotation combined with a recycling of waste through composting (from the cities back to the farms,) will actually be sustainable pretty much forever, as shown by the fact that our forests and such still exist.

Two things to solve the food crisis: high density farming, and less meat. In the long run, we're going to want to start returning land to the state it was before we cleared it and set up farms. This could be done by high rise farming, hydroponics, and maybe even LEO environments, and could serve a large amount of the world's population. There's also rooftop and backyard gardens, city orchards, etc. etc.

Less meat is a very, very important thing though, because a large portion of the world eats a lot of meat, with places like North America actually having too much meat in their diets. Cutting back on that would help the food crisis a lot. Sure we're omnivores, but we were originally herbivores, and we evolved into omnivores at a time when we needed the extra energy from other animals. We certainly don't need that anymore.
If you only get 2% of the energy from the field back in beef, imagine how much food that would open up by reducing beef consumption by even half.

Gillianren
2010-Mar-12, 03:12 AM
Sure we're omnivores, but we were originally herbivores, and we evolved into omnivores at a time when we needed the extra energy from other animals.

How far back do you want to go for "originally"?

Jens
2010-Mar-12, 03:24 AM
Most experts agree that Earth can only sustainably support between 9 and 11 billion people . . . But to have Venus and Mars at 15 billion people would be thousands of years from now. Asteroids are most probably much further.


You seem to be implying that Mars, with a surface area 1/4 of the earth, has the potential to carry a larger population. That may not be exactly what you're saying. But still, if we can change Mars to accommodate that many people, surely we could do the same to the earth. Maybe we could get rid of the earth's atmosphere so that it could carry a greater population? :confused:

Jim
2010-Mar-12, 03:25 AM
Two words.

Soylent.

Green.

(C'mon, you were thinking it.)

Atraveller
2010-Mar-12, 03:49 AM
two words.

Soylent.

Green.

(c'mon, you were thinking it.)

is people!!!!

SolusLupus
2010-Mar-12, 03:56 AM
Sure we're omnivores, but we were originally herbivores, and we evolved into omnivores at a time when we needed the extra energy from other animals. We certainly don't need that anymore.

Ur? Our bodies are built biologically for omnivorism; we don't have the intestinal tracts that herbivores do. You also have to go very far back to make the argument that we were "originally herbivores". Even up to millions of years ago (much farther back I can't say), homonids were learning to use choppers and flakes to carve up found meat through scavenging (not hunting).

I think we can do with less meat, though, but I don't think we can get rid of meat altogether for everyone; there's allergies, for instance, to peanuts, soy products, etc. that some people have to deal with. However, there is the possibility of lab-grown meat for protein.

DrRocket
2010-Mar-12, 05:19 AM
There will be no wars to substantially reduce the population. It just isn't possible.
.

Russia did a pretty good approximation in WWII.

http://en.wikipedia.org/wiki/World_War_II_casualties

I think with a little effort it could be done, particulary as we are much more democratic these days and would not concentrate the deaths so strongly amoung just males.

SolusLupus
2010-Mar-12, 05:21 AM
Russia did a pretty good approximation in WWII.

One word: Nukes.

If we can have a World War without it leading to MAD, I'd be surprised.

Jens
2010-Mar-12, 06:05 AM
And the other problem is, I'm sure I'd do quite well in the presidential elections if I ran on a platform advocating nuclear war as a way to pare down the population. Generally, you have to actually get people to agree to go to war.

A much more feasible solution might be to impose forced sterilization on all babies born between say next year and 2030 or whatever. Then we'd have a real "lost generation". Or (not to be taken seriously) kill all baby boys born during those years. As a result, we'd have a real "generation X" . . .

SolusLupus
2010-Mar-12, 06:09 AM
Why kill babies? Let's just kill the old folks. Everyone above the age of 70.

Or, better yet, let's just wipe out the baby boomers.

Atraveller
2010-Mar-12, 06:20 AM
Or, better yet, let's just wipe out the baby boomers.

As a very late baby boomer - I kind of think I'll vote against that resolution...

But not to worry - there have been population crashes in the past - Black death in the 15th century reduced the population to the point where it didn't recover for 200 years.

I'm sure we will all have a lovely apocalypse (not meaning to be religious - just using a well understood term for a pare back...)

So sit back and enjoy the show...:lol:

SolusLupus
2010-Mar-12, 06:57 AM
As a very late baby boomer - I kind of think I'll vote against that resolution...

Tsk. So kill the babies because they can't vote!

The Backroad Astronomer
2010-Mar-12, 07:14 AM
One word: Nukes.

If we can have a World War without it leading to MAD, I'd be surprised.
There is a large island in the south pacific that is kind of isolated and does not have nuclear weapons. But it does not have that much of a population.

SolusLupus
2010-Mar-12, 07:16 AM
There is a large island in the south pacific that is kind of isolated and does not have nuclear weapons. But it does not have that much of a population.

And there have been proxy wars in just such countries that do not have nukes -- it was pretty much how the Cold War was "fought".

At no point did they ever even come close to the death tolls in WWII or WWI.

The Backroad Astronomer
2010-Mar-12, 07:22 AM
What we really need to do is to get the Indians and Chinese angry at each other.
(I'm just kidding)

Gillianren
2010-Mar-12, 07:31 AM
But not to worry - there have been population crashes in the past - Black death in the 15th century reduced the population to the point where it didn't recover for 200 years.

Fourteenth, but who's counting? And, of course, one of the reasons it took so long to recover was continuing outbreaks over the next couple of centuries. The last outbreak in London was 1665--the year before the Great Fire burned down the warehouse district.

Jens
2010-Mar-12, 07:39 AM
Why kill babies? Let's just kill the old folks. Everyone above the age of 70.


Well, it sounds good to me, but the problem is that people over the age of 70 are unlikely to reproduce much, especially the ones with two x chromosomes, so killing them off won't do much good. It's just a stopgap solution, if you see what I mean.

SolusLupus
2010-Mar-12, 07:39 AM
According to all the statistics, the younger people aren't going to reproduce much, so...

Sententia
2010-Mar-12, 07:52 AM
According to all the statistics, the younger people aren't going to reproduce much, so...

I'll probably only have one someday.. I wouldn't want to bring someone into the world.. knowing that the future will be harder for them, than it was for me.

SolusLupus
2010-Mar-12, 08:18 AM
I'll probably only have one someday.. I wouldn't want to bring someone into the world.. knowing that the future will be harder for them, than it was for me.

It every couple had only one child, that would put the birth rate below the death rate.

Jens
2010-Mar-12, 08:27 AM
It every couple had only one child, that would put the birth rate below the death rate.

In the long-run, yes, but not necessarily in the short-run. China's population is still growing despite the one-child policy, simply because the population is aging. But China is actually going to have a catastrophic demographic crisis at some time in the next few decades, because the population will end up stabilizing and then going into decline, and as this happens, they may end up with more retired people than working age population. Something like that happened to Singapore, and one of the shocks they discovered is that while it is easy to stop people from having babies through policies, it is very difficult to get them to have more.

SolusLupus
2010-Mar-12, 08:58 AM
In the long-run, yes, but not necessarily in the short-run. China's population is still growing despite the one-child policy, simply because the population is aging.

And the one-child policy isn't 100% enforceable in the first place. Lots of land to cover, and much of it out in the countryside.

HenrikOlsen
2010-Mar-12, 11:49 AM
If you only get 2% of the energy from the field back in beef, imagine how much food that would open up by reducing beef consumption by even half.
If you get 2% of the energy of the field back in beef, it's still a damn lot more than you'd get without the cattle if you can't grow anything edible in the field.

What you're forgetting is that the cows in a large part of the world is a means to make marginal soil that couldn't grow human edible crops into a food producer by letting the cows to the conversion to food.

Bluevision
2010-Mar-12, 02:09 PM
You seem to be implying that Mars, with a surface area 1/4 of the earth, has the potential to carry a larger population. That may not be exactly what you're saying. But still, if we can change Mars to accommodate that many people, surely we could do the same to the earth. Maybe we could get rid of the earth's atmosphere so that it could carry a greater population? :confused:Mars very well could be at the level of Earth in population, that's true. But I think for surface area, Mars will have a lot more people, probably packed into equatorial costal cities where they'll be close to farms and a warmer climate. So maybe Mars will have 6-10 billion people then? That does sound better. The biggest problem I see is food production, considering that there'll be significantly less sunlight than on Earth, and there won't be a lot of arable land outside the short tropics area close to water. Mars will inevitably be colder than Earth (though we could pump in more GHGs and lower the difference,) so that'll mean less precipitation and shorter growing seasons in most places. I'm guessing that we'll use mirrors to heat up certain areas and allow farming at night. In (right now maybe a theoretical,) eco-friendly future, I don't think we'd do that on Earth for the possibility of damaging natural ecosystems and heating it up too much.
Of the inner planets, Venus has the biggest potential for population, imo. I'd see several things happening there. First of all is the abundant energy for electricity and manufacturing, and a lot of sunlight and warmth for growing foods, in space too. If we start on the planet in sky habitats and floating cities, there's inevitably going to be more infrastructure there once it gets terraformed, meaning there'll be a possibility for large population centres on the planet surface and in the sky, and a lot of food for them. So maybe even plateauing at 20 billion in the very-very far future.

Bluevision
2010-Mar-12, 02:14 PM
Oh actually, another thing OP, I doubt that immortality will ever actually happen. Maybe the median age will be raised to 100 or something, but 1) The human body just wasn't made to be that old, and 2) I think plenty of people at those ages care less about death. 80 year olds could be doing the activities of healthy 50 year olds, but there comes a point that it all kind of stops. It's evolutionary to die at some point, and I'm guessing that new routes in philosophy and religion will address some more points to that.
Oh yeah, my point. So if people are eventually going to die, then once we get past the population spike where the population of the last 4 generations have been compounded together and older people in those generations start dying, I imagine we'll see the population of most countries start to plateau, probably drop in many industrialized countries.

HenrikOlsen
2010-Mar-12, 02:28 PM
You seem to be implying that Mars, with a surface area 1/4 of the earth, has the potential to carry a larger population. That may not be exactly what you're saying. But still, if we can change Mars to accommodate that many people, surely we could do the same to the earth. Maybe we could get rid of the earth's atmosphere so that it could carry a greater population? :confused:
It's not that much smaller that the above water surface area though.
The size difference isn't as bad as you make it look.

If is however farther from the sun and as sunlight is ultimately the limiting factor on long term equilibrium population size, that does suggest a lower possible population density.