Is there enough oxygen for a growing population? | Hacker News Reader

Is there enough oxygen for a growing population?

greenlineprint.com

16 pointsrolph24 comments

Saved you a click:

"Luckily, the amount of oxygen already stored in the atmosphere is very large and 90% of all living biomass on Earth are oxygen-producing plant matter, whereas most of our oxygen comes from deforestation-proof oceans. Our oxygen reserves are so large, in fact, that if photosynthesis suddenly stopped and all 7 billion people were stuck on our planet with no other life forms and no fire, it would take about 50 million years to breathe up all the oxygen our atmosphere has stored."

> 50 million years to breathe up all the oxygen our atmosphere has stored

Surely CO2 level would reach unsustainable levels long before that? IIRC it would only need to increase to ~0.5% before air would become unbreathable for more than a few hours..

But fire though

Hence “no fire”.

> deforestation-proof oceans

I don't know about that - ocean warming can be pretty effective at killing ocean life which is a form of 'deforestation'.

Good to know floods, draughts, heat waves, wild fires and their effects on out food supply chain will threaten our existence long before we suffocate. That is one less thing to worry about.

They have always threatened our existence. Humanity almost died out in the last ice age.

Our development endeavors us to control and mitigate these conditions. So even if development makes them worse than they would be, development makes them also more easy to manage.

The fact that society can't even shift to sustainable technologies that are available today goes to show how your point is naïve at best, dishonest at worst.

There are many people dying today from effects of climate crisis that would disagree with this whole affair being easier to manage, if only they could speak.

> There are many people dying today from effects of climate crisis that would disagree with this whole affair being easier to manage, if only they could speak.

Indeed.

But fewer people are in abject poverty today than at any point in the last two centuries — approximately 965 million in 1820 when the world population was a 1.08 billion, versus approximately 700 million in 2017, and higher than that in all intervening years — because while improvements have been imperfectly distributed, they have actually happened.

And for many of them, the renewable options are the cheapest ways to rise out of poverty.

I wonder how this distribution of poverty looked like before Europe's expansion, enslaving Africa. How much of this improvements are actually just fixing a problem that progress itself created.

I assume it was just as bad in pre-industrial Africa as it was everywhere else, though it is reasonable question.

Yes.

It's down 4ppm / 0.00002% per year in the air but reserves are so huge it's not a concern.

(I figured some would like a quick summary, but read the article anyway. I know nothing about the topic)

(I will remember from this article that a human needs the amount of oxygen produced by 7 huge trees)

the article makes a good start but has some chinques.

example is OSHA requirement for 19.5% Oxygen in a safe atmosphere.

Dumb clickbait. The Earth is 32% oxygen by mass.

On a positive note, all terrestrial water (the fraction not below ground) will eventually blow off into space because the hydrogen disassociates at the exosphere interface, approximately a billion years from now. At that point, the Earth will be a lifeless desert above ground. It's possible some life could live below ground as thermophiles for another 1-2 billion years until the Sun EZ-bakes the planet.

For the placenta to be able to sustain a fetus, the oxygen concentration in air must not drop below 17% (for humans that have adepted to the Andes and Himalayas). That is way higher then the 13% we need to breath. Also, almost all forrests are oxygen neutral. Only in the high north plant material can not rot as fast as plants can produce it. So the whole article is full of ... less then ideal assumptions.

I've never seen the specific "17%" figure before, do you have any links to studies about that? I'd love to read them!

The article talks about trees and how many we need to sustain our consumption. As far as I know, roughly half of produced oxygen comes from the ocean, primarily produced by algae.

Seems pretty strange to publish an article about oxygen reserves if you don't even know where the oxygen comes from.

Also consider that climate change threatens the algae responsible for this oxygen we breathe. It also threatens forests with increased frequency and severity of forest fires, not to mention the deforestation we ourselves are responsible for.

I wouldn't be surprised if this oxygen problem becomes a real problem much sooner than the article estimates.

Yes. There's more of a concern over "negative CO2 budget", not only due to global warming but because it has adverse effects on cognition and tends to be more concentrated in urban areas.

Short answer: yes. This is an amusing question, but there is no problem.

The "growing population" statement is misleading, anyway, because it is temporary. The fertility rate is plummeting. About 2/3 of countries are already below replacement rate, many far below, and countries are already worried about the demographic shock from dranatically decreasing populations: https://www.visualcapitalist.com/worlds-plummeting-fertility...

The demographic collapse isn't currently as obvious only because it takes a long time for people to die :-).

The bigger worry is dramatically decreasing population sizes over the next few centuries.

That will reverse once people feel less overpopulated and systems to properly compensate women for going into labour are developed.

yikes

Or cloning vats are invented...

> and systems to properly compensate women for going into labour are developed.

I don't see the correlation in developed countries.

I'd say by the time most women consider children (30s) they are past their biological prime (>30 used to be considered geriatric pregnancy).

Our entire social values would need to change to reverse that trend - career, education, values.

Even if they invented a way to bypass pregnancy completely the commitment of raising multiple children is incompatible with modern values.

Lengthening generations is a way for everyone who wants children to have them and still slow or remove the rate of growth. It would mean reducing/eliminating living great-grandparent/child relations, and make grandparents elderly rather than simply in their 50s.

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