Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

The world has probably passed peak pollution

sustainabilitybynumbers.com

Post reply on HN
Print view View original

361–370 of 383 posts

Re: The world has probably passed peak pollution

#361

Post by jl6 »

colechristensen wrote: post #313
jl6 wrote: post #205

Earlier quoted context omitted.

Conventional wisdom on population growth is that it’s a solved problem and that the population will inevitably stabilize or decline. I say let’s not count our chickens just yet. There are still countries and groups where the growth rate hasn’t stabilized at all, and even if these are small today, exponential growth means they soon won’t be. Population growth will continue until everyone agrees it shouldn’t.

It’s nothing about agreement. Everywhere has declining birth rates once they hit a modern standard of living for at least a couple of generations. Not because people think fewer children are a good idea, but because having many children in modern world is unpleasant and very few want more than two. I think it mostly has to do with increasing desires for a high standard of living when it becomes possible and the press…

While we do observe a trend towards lower fertility rates as wealth/health/modernity increases, this isn’t universal. For example, there is a big gap between the fertility rates of religious and non-religious people in the arguably modern USA. It only takes one such group to carry on the tradition of exponential growth.

Re: The world has probably passed peak pollution

#362

Post by jl6 »

nostrademons wrote: post #321
svnt wrote: post #311

Earlier quoted context omitted.

You’ll have to provide a lot more context for this to be believable. Maybe it is an unrealistic goal for animals who aren’t interested in having a stable global population.

It follows naturally from differential equations that describe population: dPop / dt = fertility rate * pop (birth rate) - deaths Note the "current population" factor in that. As long as the number of births depends on the current population (i.e. anyone has a chance to give birth), this equation will result in an exponential curve. If the fertility rate is greater than replacement rate (that "deaths" term that I've…

Right, but what most people mean by stable population is a population that doesn’t fluctuate outside of a range. A population that grows and shrinks but has some kind of negative feedback that causes it to oscillate around a value, is stable enough, even if the local behavior of the curve is exponential.

Re: The world has probably passed peak pollution

#363

Post by CatWChainsaw »

MaxHoppersGhost wrote: post #29
bamboozled wrote: post #3

Positive on the one hand, stupid it took us this long on the other.

Posted from a huge house with air conditioning while using multiple petroleum products (iPhone/computer, chair, desk, fleece, etc). The pollution lifted every single person’s standard of living across the globe to levels unimaginable 100 years ago. It’s easy to be in Seattle or New York and say we gotta stop burning oil and coal but there are trade offs that were worth making. If you live in a developing country with…

This argument is literally a comic, which makes you nothing more than a joke.

Re: The world has probably passed peak pollution

#364

Post by nostrademons »

jl6 wrote: post #362
nostrademons wrote: post #321

Earlier quoted context omitted.

It follows naturally from differential equations that describe population: dPop / dt = fertility rate * pop (birth rate) - deaths Note the "current population" factor in that. As long as the number of births depends on the current population (i.e. anyone has a chance to give birth), this equation will result in an exponential curve. If the fertility rate is greater than replacement rate (that "deaths" term that I've…

Right, but what most people mean by stable population is a population that doesn’t fluctuate outside of a range. A population that grows and shrinks but has some kind of negative feedback that causes it to oscillate around a value, is stable enough, even if the local behavior of the curve is exponential.

That sort of sinusoidally oscillating population is certainly possible, but be careful what you wish for. The negative feedback, as far as population is concerned, is "death". Before the exponentially-growing post-Industrial population, we'd have periodic wars/famines/plagues that result from the population of an area outgrowing its local carrying capacity. That's not generally considered a good thing.

Re: The world has probably passed peak pollution

#365

Post by jl6 »

nostrademons wrote: post #364
jl6 wrote: post #362

Earlier quoted context omitted.

Right, but what most people mean by stable population is a population that doesn’t fluctuate outside of a range. A population that grows and shrinks but has some kind of negative feedback that causes it to oscillate around a value, is stable enough, even if the local behavior of the curve is exponential.

That sort of sinusoidally oscillating population is certainly possible, but be careful what you wish for. The negative feedback, as far as population is concerned, is "death". Before the exponentially-growing post-Industrial population, we'd have periodic wars/famines/plagues that result from the population of an area outgrowing its local carrying capacity. That's not generally considered a good thing.

Death is not the only thing to inevitably reduce population - there's also taxes. As in, give subsidies to childbearers in eras where the population is too low, and take them away when the population gets too high.

Re: The world has probably passed peak pollution

#366

Post by nostrademons »

jl6 wrote: post #365
nostrademons wrote: post #364

Earlier quoted context omitted.

That sort of sinusoidally oscillating population is certainly possible, but be careful what you wish for. The negative feedback, as far as population is concerned, is "death". Before the exponentially-growing post-Industrial population, we'd have periodic wars/famines/plagues that result from the population of an area outgrowing its local carrying capacity. That's not generally considered a good thing.

Death is not the only thing to inevitably reduce population - there's also taxes. As in, give subsidies to childbearers in eras where the population is too low, and take them away when the population gets too high.

The problem with taxes & subsidies is that their discriminatory power is not as great as policy makers would like to believe. They tend to either not work at all, or they work too well and overshoot the target. (This is the issue with many other economic interventions as well.)

Economists like to pretend that everything is a continuous function of price, but this very rarely reflects real markets. Most utility functions are step functions; there is some point at which changing your behavior becomes economical, and above it everybody switches, while below it nobody switches. People can either afford to raise a child in the lifestyle they expect, or they can't - and many of the sacrifices in lifestyle don't move the needle in fundamental living costs. For having a child, that point appears to be in the hundreds of thousands of dollars. If you make childcare and college free and give 2 years of maternity leave and ensure that you can buy a 3BR+ house on an average income, then sure middle-class people will start having kids again. All the middle class people will start having kids again, because they all face the same economic constraints. And then you'll have fertility > 2 again, and the population will start exponentially growing.

You could have a large per-child subsidy and cap at 2, but this also is a lot harder to generate the desired effect than expected. Accidental pregnancies are a thing. Twins are a thing. Infertility is a thing. Careers are a thing. People who want to remain childfree regardless of cost are a thing. If you cap at 2, you'll get a fertility rate under 2 because of all these other considerations.

And this is what's playing out empirically across many countries right now. A lot of European countries have generous subsidies for childbearing; they still find that they can't raise the fertility rate above 1.5 or so. China lifted its one-child only policy, moving it to 2 children in 2016 and 3 children in 2021, and finds that fertility still collapsed (even after instituting subsidies) and they can't convince people to have babies. There are significant non-monetary costs to parenthood; it's a whole other lifestyle, and the money involved needs to be pretty large to alter that.

Re: The world has probably passed peak pollution

#367

Post by dalyons »

soperj wrote: post #123
dalyons wrote: post #85

Earlier quoted context omitted.

Also critically they don’t have to build these coal plant to be economically used in the same way as free market states do. They’re building them mostly as a hedge - if they end up barely used , which is likely given renewable trends, that’s ok for state owned power. It makes everything a bit more expensive, but you can’t exactly vote for an alternative. If they need to get used a lot for whatever reason, no one is u…

How do you vote for an alternative in the US?

If a state gov made choices that made power way more expensive than it should be, and people get upset enough it theoretically could hurt them in an election. I realize this hasn’t happened in California but it’s possible

Re: The world has probably passed peak pollution

#368

Post by missedthecue »

adrianN wrote: post #353
nostrademons wrote: post #321

Earlier quoted context omitted.

It follows naturally from differential equations that describe population: dPop / dt = fertility rate * pop (birth rate) - deaths Note the "current population" factor in that. As long as the number of births depends on the current population (i.e. anyone has a chance to give birth), this equation will result in an exponential curve. If the fertility rate is greater than replacement rate (that "deaths" term that I've…

Luckily there are many fertility rates that are indistinguishable from "stable population" over a span of a couple generations, say 100 years or so. That means there is plenty of time for policy shifts to incentivize or disincentivize having children.

At current fertility rates, Europe's population is going to halve in 3 generations, and who remains is going to be quite old on average. I don't know your age, but if you're young enough this will happen within your lifetime. It's not a distant and abstract problem.

I am not accounting for immigration of course, but from the wider point of view, immigration is musical chairs. Sri Lanka is well below replacement and still falling fast. Who is going to immigrate there? Ditto for most other countries.

Re: The world has probably passed peak pollution

#369

Post by jandrese »

adrianN wrote: post #354
jandrese wrote: post #257

Earlier quoted context omitted.

There is a lot of panic over shrinking population where people project it out 1000 years and find there are only like 5 people left in the world. Steady state population should be the long term goal, at least until we start moving into orbital colonies or something. But unfortunately that's an anathema to growth oriented economies which makes it the bad guy in economics and politics.

Moving to orbital colonies won't save you in the long term if growth remains exponential. You can expand at most in a sphere growing at the speed of light so at O(t^3). Eventually the O(c^t) population growth will outpace the rate of expansion.

Projecting out exponential growth into the far future is great because it has happened exactly never in history. All growth is on an S curve. Always.

Re: The world has probably passed peak pollution

#370

Post by casercaramel144 »

Lammy wrote: post #248
casercaramel144 wrote: post #115

Earlier quoted context omitted.

So by the tyranny of exponential growth, we should just start building massive breeding factories and forceably enslaving people randomly matching them to have children? Because this could actually be the optimal policy if we take your view of "second persons" to it's optimum. In your world governments forceably breed humans like chickens in massive factory farms churning out people to the carrying capacity of the pl…

> Because this could actually be the optimal policy if we take your view of "second persons" to it's optimum. Maybe if you're evil enough to not care about any individual human's quality of life. Is there a word for the logical fallacy where you argue against the most absurd possible interpretation of a person's beliefs in order to feel no guilt for disregarding them?

The idea is that due to exponential growth, amortized over long enough times, the utility of a person's happiness right now is 0 compared to the utility of filling the planet with lets say hundreds of billions of people with barely alive standards of living. Even if an individual persons life is 100x worse than present day, it doesn't matter since there are billions more of them.

This is the standard issue with any aggregate utilitarianism theories of morality.

https://utilitarianism.net/population-ethics/

It's a stupid idea that's been soundly rejected because it posits arbitrarily bad living conditions since "anything" is better than nothing.

Post reply on HN