1) Limiting number of children in rich countries. This is what your links talk about I think. Yes, perhaps there is a taboo in place here.
Is that relevant to sustainability crisis though? Population is already declining in rich countries, quite naturally.
2) Limiting number of children in poorer countries. Well, as in the article pointed to in a sibling comment, "Richest 1% account for more carbon emissions than poorest 66%"...
So by saying that overpopulation is the root of the crisis -- are you not saying that it may be better that 10 poor people are not born, than for rich people to do minor changes to their lifestyle?
The global population is still increasing. Furthermore, as poor countries develop this is compounded by increased consumption (both resources and energy) per capita. In that respect, "richest 1% account for more emissions than poorest 66%" should be interpreted as very worrying when the poorest are getting richer.
Ultimately we don't anyone to be poor. At current population levels this would probably mean a total collapse of the environment.
Overall, the global population is indeed the root cause of our problems.
To have that position you basically need to reconcile two positions that to me aren't really compatible, unless someone explains it to me.
Either it's fine for Earth to not have humans and just exist peacefully with the rest of the ecosystem until another lifeform takes over.
Or it's not fine for the Earth to have no more humans and so we need to stop climate change from making the Earth uninhabitable for us, but if to do that we want to reduce the humans, I don't get it.
To "kill" humans to save humans seems weird. I guess you can slide on the scale of "more people living worse", or "less people living better", but to choose who is not possible in my opinion, so this is not implementable.
Because if you care about the Earth primarily, then warming or not doesn't really matter, it's just a geological event like many more gnarly ones over the history of meteorite impacts and so on.
But if you care primarily about the humans, then how can the answer be to have less of them? And pick and choose who gets to reproduce?
Population is already naturally decreasing in a fair number of countries. Let's embrace this instead of panicking and trying to reverse the trend.
I definitely would say that and would argue it needs to be way more than 10.
If you want to solve manmade climate change you need to solve the demand for goods that cause it. You lower demand by increasing the the supply (can't do that because that increases the emissions you try bringing down) or you increase its price making only the very rich able to afford it and delaying the problem for a decade till population catches up. We already see it with migrant crisis all over the west - both Europe and US.
You do this decade after decade, again and again each time creating more and more privileged cast that can afford it (current policy) and in essence pushing the rest of the civilisation further and further into poverty as they will never catch up and if they do - new legislation will bring them down again to mask the issue once more.
An example of that would be farmers in Europe protesting removal of diesel subsidies or just in general people being able to afford smaller and smaller cars due to taxation in Europe every year.
The problem with these "minor changes to their lifestyle" is that they need to accommodate exponentially growing population that already is a magnitude or more higher than persons who need to adjust.
We are talking about 90%+ reduction in what you call "minor changes" to achieve emission equilibrium to begin with and add that with exponentially growing population and its simply not feasible not due to lack of compassion from top percentile but because changes like these would completely anihilate the modern human civilisation and bringing it back hundreds of years.
As an example theres a very informative video on what happens to country and infrastructure when 4 million people join the power grid in a decade [1] Imagine that scaled to 4 billion and the extreme worldwide devastation.
Population control is the only way to solve climate change and it needs to be reduced everywhere but especially in the undeveloped nations as they have the most potential of bringing everything down.
Jevon's Paradox[1] states that as efficiency increases (which itself is a form of supply increase), demand increases.
My own view is that the paradox makes the idea of population reduction moot, those remaining humans would simply use more energy because supply has gone up and demand (through lack of competition) going down to levels below supply would, again, drive prices down.
The bulk of what I value about the future of humanity is our continued existence and collective ability to do beautiful and impressive things together, not the individual existence of some as-yet-unborn hypothetical humans in that future. I don't think humanity's output scales linearly with population and I don't think there's much moral worth to future individuals outside their general contribution to wider human civilisation.
There is no consistent way environmentalists can argue their way out of this particular point you made:
> But if you care primarily about the humans, then how can the answer be to have less of them? And pick and choose who gets to reproduce?
To somebody else it means just living life.
There is no way to objectively argue superiority of one over the other except from a religious worldview.
This looks to support my argument as its indeed what is happening and what is causing emissions to go up (less developed nations industrialising) due to technology trickling down. Please correct me if i'm wrong.
> My own view is that the paradox makes the idea of population reduction moot
Lets use math and assume all pollution comes from end users who can afford/drive cars (~20%) and ignore the rest of modern civilisation and set current efficiency of 1x.
8 000 000 000 * 0.2 * 1 = 1 600 000 000
Lets call the 1.6Bil a hard line that we want to sustain aka the perpetual enviormental doomsday in the current year+x.
Over the next 80 years with strict population control and current technology we can make that:
4 000 000 000 * 0.4 * 1 = 1 600 000 000 and bring 20% more people into the top percentile bringing the misery, disease, war and resource shortage down or keep it to its current form.
Or if we wanted to bring same 20% of population to the same mark with efficiency (11.2 bil is expected population by 2100) we would need to achieve efficiency of:
11 200 000 000 * 0.4 * x = 1 600 000 000
x = 1600000000/(11200000000*0.4) = 0.357
Thats an efficiency increase of ~2.8x
So it boils down to you claiming that in the next 80 years we can increase efficiency 2.8 times across the board. This does not only include energy but materials too 2.8x less materials used to build cars, houses, roads etc. And on top of that we will do it with a completely new source of energy since fossil fuels are going dry in the coming decades.
Furthermore you calling population growth moot suggest thinking that this can be repeated again ad infinitum in 2180 and 2260 and so on.
I'll put it mildly - don't think its feasible.
Edit: fixed the last calculation for clarity/typos
> The issue is the global population. Obviously, that's the metric that matters for global issues like the climate and environment.
Look, what if you could choose between:
Option A: The 50% lowest polluting part of the world's population never existed. Would this make a dent towards global warming? No. Perhaps slow the onset by a few years. The overall magnitude of the problem would be the same.
Option B: Through reduced consumption and technology, reduce emissions of the 50% highest polluters by 80%. This would have a quite massive impact towards global warming AND also help when the 50% poorest increase their living standards.
Given these -- how can you say that "population" overall, without further qualification, is the problem?
Another factor here is that population growth isn't something that will continue as/if people are lifted out of poverty -- when people become richer and more educated, the birth rates invariably drops.
There are many other good comments on this page now about why you are wrong citing statistics and research reports, I encourage you to read them.
And both are a function of the population and are people get out of poverty use of energy and resources per capita only increases, compounding the overall impact, as already said.
If we were 500 million globally, for instance, we would not be having this discussion because there would be no problems.
I am not wrong, this is just a statement of fact. I am always surprised by this ostrich syndrome many have in absolutely refusing to consider that population is an issue, the key issue, even.
If you care about the well being of dogs, how can the answer be to have less of them crammed in your tiny apartment?
It’s about balance. It is not true that more of something is unambiguously good, for itself or the system as a whole.
You should read about how reintroducing wolves, a carnivore that kills other animals, made the Yellowstone ecosystem flourish.
https://www.yellowstonepark.com/things-to-do/wildlife/wolf-r...
Or the case of Macquarie Island.
https://archive.is/2020.10.21-044800/https://www.nytimes.com...
Or the deer of Manitou Island.
https://www.interlochenpublicradio.org/2022-03-04/unnatural-...
Or, or, or. We have tons of examples.
> If we were 500 million globally, for instance, we would not be having this discussion because there would be no problems.
But this aside, let's assume you are right.
Which 500 million would you preserve? How would you get there before climate change is irreversible anyway due to melting tundra etc?
Especially given that a lot of human history can be summed up as "wars to determine WHICH one will be the surviving set of humans to survive on limited resources". So which billions do you think will go willingly?
-- Yes, of course, assuming that this magically just happened it would solve the problem. So would a number of other unrealistic solutions that has nothing to do with population control. Are we going to discuss which one out of a number of completely unrealistic uptopias are best?
I see your 500 million inhabitant world, and raise with imagining a world with a population of 20 billion, with a million nuclear plants, no use of fossil fuels, LED-powered vertical farming, centralization of populations in big cities to let wildlife grow back and focus all efforts in responsible, non-disruptive mining of the resources needed.
Which one of those is more or less preferable or realistic is pointless, and distracting from possibilities that may be within reach.
It was approximately exponential up until around 200ish AD, fell below exponential for a few hundred years, then was above exponential for around 600 years (the growth rate was going up approximately linearly), had a period where it varied and even was slightly negative, and then around 1500ish entered a period where the growth rate was increasing almost exponentially. That lasted to around 1960, and since then the growth rate rapidly.
Here's a graph of the growth rate from 4000 BC to 2023 [1] from the data here [2].
I was curious what it is called when the growth rate itself is going up exponentially, but utterly failed to craft a search in Google that worked for me. I then tried ChatGPT (the free version) and at first it was just wrong. I reiterated that I want to know what it is called when the growth rate is going up exponentially, not when the growth is exponential. It apologized and told me it is called "exponential growth of the growth rate" or "exponential acceleration".
I tried to verify that it is called "exponential acceleration" with Google, but failed.
Regarding the superiority of worldviews, sure, subjectivity applies and we could go down the rabbit hole of discussing that - but the comment I was replying to was not about which worldview was better! Vasco said that "Either it's fine for Earth to not have humans ... Or it's not fine ... but if to do that we want to reduce the humans, I don't get it." I'm not going to argue that my values are the best because it's already self-evident to me and I doubt I can improve on the existing work[0], but I am very willing to explain how they're logically consistent.
[0] Via utilitarianism and the repugnant conclusion and onward. I don't think I can do any better than all the philosophers who've debated this.
I mean, you might as well quote me a list of your very personal niche hobbies and the importance of keeping them up as some kind of tradition humanity needs to uphold.
I don't think such a line of argument holds very tight in the grand scheme of things.
To others, enjoying the company of their own children and grandchildren (some of the most commonly shared joys across people, in contrast to niche interests) are far higher up there on their list of priorities of things that make our existence worthwile.
Likewise, utilitarianism won't get you far since the other person must first subscribe to it as a good idea. I don't care about "the greatest good for the majority" in some kind of vague sense whatever it means, if subjectively it means no good to me.
The derivative of the exponential function is the exponential function.
d/dx eˣ = eˣ
So if it’s growing exponentially the rate of growth is exponential and the rate of that acceleration is also exponential.
One is to look at host much its value changes as x goes to x+d, and divide that to d to get an average rate of change from x to x+d. Take the limit as d -> 0 to get the instantaneous rate of change at x.
That gives a rate of change of Limit as d->0 of (F(x+d) - F(x)) / d, which is pretty much the textbook definition of d/dx F(x).
The other way is to look not at the actual value of the change but rather how much of a fraction of F(x) it was. That gives this measure: ((F(x+d)/F(x) - 1) / d. The instantaneous value would be the limit as d -> 0. That limit is of the form 0/0, but using L'Hôpital's rule we can turn it into (using the notation F'(...) for d/dx (F...)) the limit as d -> 0 of F'(x+d) / F(x) which is F'(x) / F(x).
When people talk of growth rate they usually mean this second measure. The first is usually called the rate of change. BTW, note that rate of change and growth rate are related. The growth rate is the rate of change of log(F(x)).
Exponential functions have an exponential rate of change but a constant growth rate. It is that constant growth that makes the concept of a half-life work for things that exponentially decay.
Redo those calculations as if the paradox has weight and see where you end up.