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Jancovici famously made the calculation in public in 2003: If you divide permissible emissions (3Gtec/yr) by Earth population, each human can EITHER:

- Use one Paris-NYC flight per year,

- OR eat meat,

- OR heat their home,

- OR drive to work.

Choose one. All EU calculations about emissions are based on this target, but it’s too early to tell people. It’s based on: Earth absorbs 3 gigatons-equivalent-carbon by night, so we can emit as much. And that’s what humanity emitted in 1990, so it’s achievable. Since then, we’ve double or trippled.

For myself, I consider that the only flaw in this reasoning is that dividing the global permissible emissions by population “is communism”, because it assumes that every human should be given the same pay. I consider it’s normal that some earn much more. That’s the only flaw, and that’s because I’m a capitalist, but it’s great to have the ballpark figure of what would be FAIR to consume for everyone.

(I also have doubts about scientists’ reliability when topics are heavily politicized, but that’s my affair, at least I’m repeating their conclusions as-is, so you can judge).




> And that’s what humanity emitted in 1990, so it’s achievable. Since then, we’ve double or trippled.

Note that global population in 1990 was 5.3 bn vs 7.4 bn in 2022.

That doesn't mean it isn't achievable - but it's implies a significant per-person reduction to achieve 90s levels.


To me, this is where direct air capture and geoengineering come into play: there's a saddle point where we (as a planet) can afford to pay to increase consumption and offset emissions above that.

Which is why globalizing a carbon market is so key. It organically (ha) funds what we want people to be researching and doing anyway!


This is misleading and creates the illusion that sustainability is impossible.

Instead, only the fraction of population using more that their fair share is responsible for reducing emissions.

And we can very much reduce meat consumption and car usage, improve home insulation, and fly around much less.

And do that while improving health, life expectancy and quality of life.


> Instead, only the fraction of population using more that their fair share is responsible for reducing emissions.

What is “fair”?

Again, it isn’t fair that a country can emit more, just by having more population.


Why would you _not_ divide up emissions by people? (And especially by country, if that's what you're trying to say.)

Countries don't need to eat, countries don't live in homes that need to be heated, countries don't need to get to work, countries don't travel, etc etc etc, _people do._


> Why would you _not_ divide up emissions by people?

Because then you give an incentive to reproduce like rabbits, to be familiar. And reproducing too much is 90% of the reason why we’re terraforming all our forests and swamps. 90% humid zones of Earth have been urbanized in the last 30 years.


Citation needed.


As capitalist you should recognise that permissible emission as a capital, not pay.

Of course you could distribute that capital by free market optimisation. But before there can be buyers there must be sellers. Who has the first claim of those permissible emissions?


Emissions are so close to how much you spend. Don’t fly but spend the airfare money on Chinese toys: Same carbon emitted. So having the right to emit n teq = having the right to spend m money.

So emissions are a flux and emission permits are capital, you are right, but it’s just a philosophical argumenation, like photons are both a particle and a wave, and real estate is both capital and a currency.

Maybe your question was, how do we impose others to not emit carbon, how do we set up the first emission permits. Well that’s hard. But it doesn’t matter - They should have a price and change hands when someone can afford them.


I was alluding to the geo-libertarian position that the ”fair” distribution or ”land”(in the economical sense) is fully compatible with capitalism, and not necessarily communism.




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