How much population would earth hold?

[fredreload]

How much population do you think earth can hold? Keep in mind that 70% of the landmass is sea and we don't really live in sea or submarines like some people do, but it is a viable option.

[Phi for All]

Too many variables. We could probably sustain 9-10B people doing what we're doing now, but we could sustain many more if we changed the ways we used our resources. And as you mention, there are habitats we haven't needed to explore that would become viable if we were trying to maximize our population. New technologies are also hard to factor in, but growing our own proteins (like cultured meats) would have a significant impact.

[dimreepr]

12 minutes ago, fredreload said:

How much population do you think earth can hold?

We'll probably, suddenly, find out when it no longer can; although, when I come to think of it, you're going to have to define what species you're talking about...

Edited August 27, 2019 by dimreepr

[Phi for All]

1 minute ago, dimreepr said:

you're going to have to define what species you're talking...

I don't think we need to overthink this thread to the point of meaninglessness. Can't we assume the OP was talking about human populations when they said "we don't really live in sea or submarines"?

[dimreepr]

Just now, Phi for All said:

I don't think we need to overthink this thread to the point of meaninglessness. Can't we assume the OP was talking about human populations when they said "we don't really live in sea or submarines"?

Indeed, that's why I put it as an after thought, my point being that however much we fuck up the planet for us, life will persist (until it can't).

[Phi for All]

20 minutes ago, dimreepr said:

Indeed, that's why I put it as an after thought, my point being that however much we fuck up the planet for us, life will persist (until it can't).

OK, please consider your point made.

Also please, please consider NOT continuing to belabor it. The OP doesn't really give you the opening to yank the train onto this particular track. It seems obvious this is a straight-up "How many people could the planet sustain" kind of question. You should start another thread about other life persisting after human mistakes. 

[dimreepr]

4 minutes ago, Phi for All said:

It seems obvious this is a straight-up "How many people could the planet sustain" kind of question.

And we won't know, until it can't.

Whom so ever our ancestors turn out to be. 

[StringJunky]

50 minutes ago, dimreepr said:

And we won't know, until it can't.

Whom so ever our ancestors descendants turn out to be. 

FTFY 

Edited August 27, 2019 by StringJunky

[dimreepr]

5 minutes ago, StringJunky said:

FTFY 

Thanks, but aren't they kind of the same?

[swansont]

I think you could estimate it based on usable land for farming and sustainable fishing yields. But you'd have to define those parameters, and what kind of diet you are supporting, and whether you had access to irrigation. We could sustain more people if you had a vegetarian diet; a lot of food gets wasted feeding livestock to that people can have beef and chicken, etc. Your options change if you have less water available. 

As it stands, too many variables, as Phi has said.

But, as a starter you have potatoes giving you 17.8 million calories per acre at the high end, and Beef at 1.1 at the low end in this small table

http://www.waldeneffect.org/blog/Calories_per_acre_for_various_foods/

So maybe you estimate 10 million. at 2000 cal per person per day, you need almost a 750,000 calories a year per person. 13+ people per acre

 

If we have 1.5 billion ha (from http://www.fao.org/3/y4252e/y4252e06.htm)  that's ~3.75 billion acres

3.75 billion x 13 = is just under 50 billion. Add in food from fishing, but you lose it to spoilage and weather. Assuming we all become vegetarians and like potatoes and corn.

This doesn't account for access to water and healthcare. Increasing our population density will have ramifications on how diseases spread.

 

 

[StringJunky]

2 hours ago, dimreepr said:

Thanks, but aren't they kind of the same?

Ancestors are before you and descendents are after you. Your post was in future tense, so I think descendants is correct.

[dimreepr]

19 hours ago, StringJunky said:

Ancestors are before you and descendents are after you. Your post was in future tense, so I think descendants is correct.

Sorry, I thought I'd posted this link in the post you fixed for me. 

 

[Art Man]

I would speculate that the Earth is already too small for the present human population. Factor in pollution, climate change, disappearing resources, extinctions and all the other negatives currently plaguing the world as a direct result of human folly and it is very obvious that we are already on a crash course with sustainability.

Now if you're asking "how many of us can we make before it all tumbles down?" then I would say 20 billion max. At 20 billion the last tree would fall and the last gallon of clean fresh water would be drunk, right before global third world chaos plays out the end of humanities' existence. Earth will take millenia to recover.

Edited August 31, 2019 by Art Man

[Sensei]

Quote

How much population would earth hold?

1) how much energy from the Sun arrives to Earth's surface? 1050 W/m^2 at max at noon at summer

2) how much of this energy can be used to grow food for human being.. ? (i.e. using GMO microbes or algae )

3) what is rate of vaporization of sea (caused by the Sun)? -> amount of rains -> availability of water for farming. With extremely extensive water usage, sea level would drop (and rivers would not fill seas and oceans anymore)..

4) what is available CO₂? (CO₂ + H₂O -> organic matter food for people)

 

 

Edited August 31, 2019 by Sensei

[Silent]

How much population can the planet sustain without a negative trend on resources or a detrimental pollution?