[wtallis]

That doesn't look like double-counting the effects of the deforestation, just breaking it down into two segments: the difference between leaving the forest in place vs. cutting it down, and then the difference between leaving the now-bare land idle vs. using it for industry.

[anthuswilliams]

No. Double counting is an effect of ascribing the emissions.

When you ascribe the effects to the Amazon, you combine the two. As a simple exercise, imagine that the deforested land had been left fallow, and the CO2 emitting business had set up shop at a different plot of land. You wouldn't ascribe the CO2 emitted by the business to the Amazon, and therefore, when you DO ascribe it to the Amazon, you are double-counting the effect.

None of this is to say that it's okay to deforest the Amazon. I just hate it when people lie with numbers for the sake of a catchy headline.

[wtallis]

> As a simple exercise, imagine that the deforested land had been left fallow, and the CO2 emitting business had set up shop at a different plot of land. You wouldn't ascribe the CO2 emitted by the business to the Amazon, and therefore, when you DO ascribe it to the Amazon, you are double-counting the effect.

Here you're assuming all the same industrial activity would have happened, just elsewhere. But that seems like an unfounded assumption that ignores how deforesting the Amazon opens up new cheap land to enable more industrial activity with lower costs than would otherwise be the case.

Land is finite and not cheap. Pretending that eg. new farming would have simply happened in the same way and quantity elsewhere had the Amazon been protected is a more egregious lie than trying to include economic activity in the net greenhouse effect of the whole Amazon.

[anthuswilliams]

That's fair. But in return, I offer the counter-argument:

When you double count like this, you are implicitly assuming deforestation ALLOWED the polluting business to occupy the new land, and they wouldn't have polluted to the same degree elsewhere (because it wasn't available, wasn't as profitable, or something else).

A totally reasonable claim! I could explore it further. But IMO one should make this claim in good faith, make it clear what you're proposing, not engage in this kind of statistical sleight of hand.

I am totally opposed to deforesting the Amazon. But I'm sick of political participants that think it's OK to lie to people, simply because the implications of the lie favor some greater truth.

[wtallis]

> A totally reasonable claim! I could explore it further. But IMO one should make this claim in good faith, make it clear what you're proposing, not engage in this kind of statistical sleight of hand.

There's absolutely no sleight of hand involved in suggesting that farming on former rainforest land is a consequence of allowing deforestation, and that the climate consequences of that farming are thus also consequences of that deforestation.

Given that enabling such farming is usually the economic driver for performing the deforestation, it's ridiculous to suggest that anyone should consider the deforestation process itself and the subsequent polluting land use as having separate causes that make the latter somehow not count as part of the Amazon's climate impact.

And even if you do honestly feel like the direct effects of the deforestation should be considered as unrelated to the effects of the subsequent land use, it is still quite incorrect for you to refer to this as double-counting. There are two different quantities being lumped together (because they are almost inextricably related), and there's no overlap in the climate effects accounted for under those two categories. It's not double-counting; it's just counting some quantities you'd prefer to sweep under the rug.

[djmips]

Oh please. The headline is garbage - don't you see that?