[wcunning]

The basic gist of the article is found about 1/2 way in:

"First, the phytoplankton in the oceans also photosynthesise [...] Therefore in terms of TOTAL global photosynthesis, photosynthesis in the Amazon contributes around 9%. [...] Second, a bigger point that is often missed is that the Amazon consumes about as much oxygen as it produces."

This reminds me, as we should all be reminded on a regular basis, the bulk of the things you read in the popular press are at best skimming the surface and at worst outright misleading due to grabbing onto one obscuring factoid instead of the most important pieces of information. Per Gell-Mann, I only see this in tech and science reporting, but that makes me really unreasonably suspicious of political reporting, too.

[Merovius]

> This reminds me, as we should all be reminded on a regular basis, the bulk of the things you read in the popular press are at best skimming the surface and at worst outright misleading due to grabbing onto one obscuring factoid instead of the most important pieces of information

FTR, this article is doing exactly that. Like, they a) divert your attention with the CO₂<->O₂ conversion (which doesn't change relative numbers in percentages of photosynthesis at all - you multiply both sides of the equation). And b) then proceeds to pretend that the Amazon eats up most of the Oxygen it produces, but the rest of the world apparently doesn't. Like, if a tree re-metabolizes 40% of the O₂ it produces, then that's also true for the 91% of O₂ produced outside the Amazon, so we still end up with the same 9% figure of all O₂ produced in the Amazon.

The article ends with the "CO₂ emission is more important". Which, again, fair. But Photosynthesis is presumably a pretty important mechanism by which CO₂ is removed from the air. So a reduction of O₂ production is equivalent to a reduction of CO₂ absorption (though you have to multiply with 2.67, don't forget!), which seems to… be a bad thing for CO₂ concentration in the air.

The gist of the article is pretty much "if you don't round and take into account maritime photosynthesis, the Amazon only produces 9% of all O₂". Which is fair. The rest is noise. It doesn't add to the argument and is just fueling the "MSM is bad!" cries…

[jefftk]

The article is making a much stronger claim:

> the net contribution of the Amazon ECOSYSTEM (not just the plants alone) to the world's oxygen is effectively zero

If this is correct, then the entire Amazon could vanish without having any effect on CO₂ levels.

[chewbacha]

It could be correct and still have an impact on CO2 levels as it is still a massive sequester of carbon. Burning it down removes the sequester and adds it to the atmosphere.

Also, just because it doesn’t produce the breathable O2 we need, that doesn’t mean it’s not part of a global system that produces and stabilizes our atmosphere. It actually is responsible for a massive silt run off that feeds the oceanic diatoms that in turn produce half of the worlds breathable O2 and fixes carbon right in the ocean.

This is a case where a literal point is incorrect but it does not decrease the importance of the rainforest to our globe.

[dcolkitt]

Some back of the envelope math... One tree in a tropical rainforest sequesters 50 pounds of carbon. The Amazon contains 390 billion trees. Since industrialization humanity has cumulative released about a trillion tons of carbon. So if the entire Amazon burned down it would increase atmospheric carbon by less than 1%.

This is just a rough estimate, and I'd encourage others to check my calculations. But intuitively this seems correct. Extracting fossil fuels releases all the carbon sequestered by organisms over 100 million+ years. Burning down a rainforest only releases the carbon sequestered by organisms currently living.

I don't see how it wouldn't be possible for fossil fuels not to contain orders of magnitude more carbon than forests. Which is of course why the switch from wood to coal precipitated the industrial revolution.

[1] https://medcraveonline.com/FREIJ/FREIJ-02-00040.pdf [2] http://mentalfloss.com/article/63519/how-many-trees-are-ther... [3] https://ourworldindata.org/co2-and-other-greenhouse-gas-emis...

[chewbacha]

I agree that burning fossil fuels release more CO2 into the atmosphere. I was not trying to imply that the rainforest will halt global warming, obviously it can’t because it’s been there the entire time.

However, I do believe just multiplying trees by weight does not accurately describe what carbon sequestration is. Trees are not the only place carbon is sequestered in a forest. Soil sediment, animals, and other plants also sequester. It’s also a home of biodiversity and nutrient run off that assists other parts of our global ecosystem. In turn, Carbon sequestration occurs over time; and it’s these rich, biodiverse ecosystems that produce the fossil fuels that we are burning, without them the carbon would never sink into the earth as it does.

Eliminating the rainforest halts the engine that cleans the atmosphere and removes the carbon and cools the earth. It would also dump millions of more tones into the atmosphere (even by your calculations). It would also disrupt global food chains which do produce our global breathable oxygen.

I’m not sure what your point is that you are making other than you imply that we don’t need to save the tropics because fossil fuels are worse; but I heartedly disagree with that implication.

[dcolkitt]

> However, I do believe just multiplying trees by weight does not accurately describe what carbon sequestration is.

That's a fair point. The IPCC gives an estimate of 109 tonnes per acre of tropical forest. Which is about an order of magnitude higher than my original estimate.

But even with those numbers, deforestation is basically a rounding error compared to fossil fuel emissions. The Bolsonaro admin has increased deforestation rates by 278%, or an annual rate increase of 4500 sq km. Using the IPCC numbers, that's 110 million tonnes of Carbon per year.

That's less than one week of America's carbon emissions. Less than one day of global carbon emissions. The point is that from a climate standpoint, current rates of deforestation are largely inconsequential compared to fossil fuel emissions. It's almost certainly more effective to spend political and economic capital on energy efficiency and renewables.

[shkkmo]

> Trees are not the only place carbon is sequestered in a forest

Trees are not the only part of the amazonian ecosystem, but I'm pretty sure trees outweigh other parts of the amazonian ecosystem by a significant ratio. I think the calculation probably suffices as a back of the envelope estimation.

> I’m not sure what your point is that you are making other than you imply that we don’t need to save the tropics because fossil fuels are worse; but I heartedly disagree with that implication.

Removing tropical rainforest would be disastrous, but not because of impact on global CO2 levels. (Its effects on CO2 levels would not be helpful but wouldn't be among the worst consequences). Among other reasons, it would significantly alter global weather patterns and cause massive damage to ecosystems across the globe.

I think the point is that even an ecosystem as massive and influential as the amazon can't even make a dent in the amount of CO2 that is being produced by human activity.

[mirimir]

That's actually pretty much true. At least, if it literally "vanished", without releasing biomass carbon back to the atmosphere.

In temperate ecosystems, there's net long-term storage of biomass and nutrients in soil. Mainly roots of dead plants. But also stuff that accumulates faster than it can decompose. Tundra and taiga are extreme examples.

But mature tropical ecosystems are pretty much in equilibrium, with ~zero net impact on the soil or atmosphere. Pretty much all mineral nutrients are locked up. And everything that dies gets recycled very quickly.

[mycall]

O2/CO2 aside, the Amazon rainforest's biodiversity is unique and has been a source for medical resource. There is more at stake than just breathing.

[RcouF1uZ4gsC]

I hear this brought up a lot. Can you name a drug that has actually passed all the safety and efficacy trials that has been developed from something in the Amazon?

[ramphastidae]

Quinine for one. There are many more if you are willing to do five minutes of research: https://www.conservation.org/blog/5-rainforest-species-that-...

[darkerside]

It's 5 minutes of research if you know what you're looking for. It can be much more if you don't, and you don't know when and where to stop.

BTW, that's kind of the entire point of a site like HN. Experts from different fields (and hobbyists and laypersons) get together and exchange knowledge. Sorry to go on about this, but I've been seeing too many responses saying to go Google things.

[mehrdadn]

> It's 5 minutes of research if you know what you're looking for. It can be much more if you don't, and you don't know when and where to stop.

I know nothing about the topic, but literally just Googled Drugs from the Amazon [1], and the very first example of the very first search result I came across was Quinine. [2]

[1] https://www.google.com/search?source=hp&q=drugs+from+the+ama...

[2] https://www.adventure-life.com/amazon/articles/medicinal-tre...

[dredmorbius]

Even an answer of the form "here's a set from a quick DDG" is more productive, and might even teach the commenter something, as it provides a fixed (even if incorrect) basis for discussion.

Given the option between not commenting at all or offering some variant of JFGI, I'll strongly prefer the former. "You don't have to attend every fight you're invited to", or comment on every post. But if you do, try to land solid punches. Even if you're not Mohammed Ali.

(I've frequently learned things, and more than once entirely changed my mind, in researching to answer comments.)

[refurb]

That first google link is shit.

has been isolated the alkaloid d-turbocuarine, which is used to treat such diseases as multiple sclerosis, Parkinson's disease and other muscular disorders.

It’s a muscle paralyzing agent used in surgery. It’s not use in MS or Parkinson’s.

I wonder what else is wrong in the article.

[topmonk]

Just type into google "drugs developed from amazon forest" and the results appear above the search results right in an answer box.

No need to wag your finger.

[RcouF1uZ4gsC]

My question was specifically about drugs that had passed safety and efficacy trials that were derived from the Amazon. Doing 5 minutes if searching and looking at your links it looks like quinine and curare are two of them. There was some mentions of some potential agents, but none that had made it through full clinical trials to be FDA approved. Quinine was first used for malaria treatment over 400 years ago. Two drugs over 400 years doesn’t seem like a lot.

And it doesn’t seem that it will get higher. My impression of modern pharmaceutical research is that instead of focusing on natural medicinal compounds, it is more focused on discovering the exact mechanisms behind various disease processes and synthesizing molecules that either slow down or speed up key pathways along those processes.

[rolltiide]

> There are many more if you are willing to do five minutes of research

but thats also how you end up on a geocities site about anti vaxxing because big pharma doesn't want you to know about the amazon and yell "exactly, I knew it all along!"

[majos]

I don't quite get the claim behind the Gell-Mann effect. It assumes that because journalism about physics is inaccurate and oversimplified, journalism about everything else is too.

But why should this be? Physics, and similar hard sciences, are deep and complex fields. There's plenty of math, jargon, and a long literature. Of course inaccurate simplifications happen when writing about it for a popular audience. Add in the weird incentives of mass media and the lack of scientific expertise among most journalists, and it makes sense that popular physics news is not so accurate.

In contrast, other newspaper topics like politics, sports, business, etc. are often literal reporting of what people do. I'm not saying any of these areas is necessarily simple, but they are at the root level about human actors, not abstract quantities that most people have 0 intuition for. So I expect that it's actually easier to do good reporting on those topics.

[rayiner]

Politics and business are incredibly complicated as well. In many ways it’s even harder to do reporting in those areas because there is no expert consensus you can consult. Is lowering corporate taxes better for the economy? There is little consensus. Even reporting “what people did” can be fraught with peril. (E.g. reporting that a company “paid no taxes” without addressing loss carry forwards.) Political and business systems, and in particular complex regulatory regimes like tax policy, are the product of many decades of refinement. Because journalists for the most part are ignorant of that history, they present every policy issue in this sort of context free way, leaning heavily on narrative and emotion to make up for their shallow understanding of the actual mechanics of what they’re writing about.

[untog]

I think where the comparison breaks down is that the laws of physics are the laws of physics. Reporting on them doesn't change them. But politics lives in the same world as reporting. It is shaped by it, politicians respond to it. So the Gell-Mann effect isn't quite accurate in that situation. Journalists do know the political world deeply because for better or worse they're involved in shaping it.

[aetherson]

I don't think it follows that people must necessarily know a lot about things they have a relatively large influence over.

[xmprt]

Your comment illustrates the point even more in my opinion. You understand more about physics than politics, sports, and business, and so you're able to see how journalists can get it wrong. However, if you actually dived into the world of sports and similar fields about "human actors" there's a lot of interpersonal relations and complexity that can't be described in a 500 word article. If journalists were just reporting about the "what" then physics would be just like reporting sports scores if you just copy the result. When you try to explain the "how" and "why" then all the complexity that you described about physics applies to sports.

[majos]

Maybe my original point was vague: I'm arguing that the "what" is simpler when human actors are involved. Person x said this, did this, accomplished that. The story is for the most part straightforward and understandable. And a lot of the reporting in these areas is just "what".

But people don't even have a good handle on the "what" of a lot of science (what are these new particles? what is p vs np?) which is why we get all these analogical half understandings.

[wcunning]

I think the bigger question in a lot of human centric things is the "why" -- why did that head of state say that thing? Why does this company avoid that regulation? Why do people complain when this tax credit goes away? It's not reasonable to stop with the "what" in many situations. Or alternatively, the comparison to physics should be an article saying that the what is the spin of a single electron in an experiment, even though the experiment is about gravity -- missing the point entirely.

And backtracking slightly to my grandparent comment, Gell-Mann was coined by Michael Creighton who in the same quote compared Murray Gell-Mann's knowledge of physics to Creighton's knowledge of show business. The "what you know well enough to spot errors" can be anything as can the "what you blindly trust the reporter on out of your own ignorance."

[Erlich_Bachman]

> I'm arguing that the "what" is simpler when human actors are involved.

Where would you get that idea? It is definitely the other way around.

In hard sciences at least you can easily construct experiments and find out truths with time, which while complex, are basically predictable. In human sciences everything is much more complex and chaotic effects and problems with definitions and inherent unpredictability of humans make everything more complicated.

[liability]

> In contrast, other newspaper topics like politics, sports, business, etc. are often literal reporting of what people do.

I was once in a local paper for my participation in a sports team. Well, my picture was. The name given to me in the article and caption was fabricated. Such a name didn't even belong to anybody else in my school, let alone on the same team!

I assume the 'reporter' was too drunk to remember my name and too embarassed to ask somebody, so he just made one up.

[DoreenMichele]

I was interviewed via email while still homeless. They assumed I was male without asking, then just made up quotes. Because the interview was by email, I have a written record of what I actually said, so I know it was outright fabricated and not some kind of misheard/misunderstood thing.

I sort of understand the misgendering. Most visible street people are male. But the fabricated quote made me feel like "They think they can just do anything they want because I'm so poor." That felt like intentionally shitty behavior.

[zaroth]

Don't worry, they do the same thing to everyone, including the President. Making up quotes, that is.

[DoreenMichele]

It's still shitty. General lack of ethics and honesty is not some moral high ground that sits above mere classism and contempt for the poor and presumed powerless.

[gamblor956]

That is extremely unusual since besides generally require release forms from people in the pictures they run.

[Monroe13]

In the US at least, no release form is required of those pictured in a news article.

[gamblor956]

In the US at least, a release form is required of those pictured in a news article by name for articles published by the AP or any major city newspaper like the NYT, Chicago Tribune, WaPo, or LA Times...

[Monroe13]

Nope, even the big publications do not use or need release forms for photos in news reporting.

If you are in public and the photo is “newsworthy” your image can be printed in a newspaper without your consent.

“Use of someone's name or likeness for news reporting and other expressive purposes is not exploitative, so long as there is a reasonable relationship between the use of the plaintiff's identity and a matter of legitimate public interest.” - http://www.dmlp.org/legal-guide/using-name-or-likeness-anoth...

[kirsebaer]

When you read news from something that you personally have been involved in, you will notice journalists simplify and often get things a bit confused.

Like, when a journalist quotes you in print, it is often not a real direct quote, but rather the journalists interpretation of what you said (which can be way off). Always insist to "check quotes" or you could get a surprise when you read your interview.

[icelancer]

>> In contrast, other newspaper topics like politics, sports, business, etc. are often literal reporting of what people do

This comment should be preserved for all time and cited in the Gell-Mann Effect entry. Do you really think physics is infinitely more complicated than finance or politics?

[mattkrause]

I'm not sure about that specifically, but reporting on politics is much closer to the paper's core competency.

The paper runs articles on politics every single day. The characters and issues don't change too quickly: Quimby was the mayor last week; next week, he'll be the same mayor, dogged by the same scandals and trying to enact the same politics too. A lot of the facts are easy to check, if someone cared to do so. The reporters may have a background in political science or history, or something somewhat related.

In contrast, the science section is pretty small. Maybe it runs once a week and has one or two main reporters, who cover everything from Astronomy to Zoology. No one has a background in all of that, and many reporters don't have a technical background at all. You can try to fact check it, but the experts themselves don't always agree and it's hard to tell whether Dr. So-and-So is really an expert on the topic anyway.

And, despite all that, the science reporting I see does a pretty good job. One of my papers got a bit of media coverage, and pretty much everyone got the broad strokes right. One place made me sound a little too exuberant about the immediate ramifications; another made me sound a bit too negative, but neither was egregiously bad.

[umeshunni]

> reporting on politics is much closer to the paper's core competency.

And despite this, most of the media got the two of the most significant political happenings of the last 5 years (US elections and Brexit) completely wrong.

[verall]

Comments like this are great.

By saying "most of media gets it wrong" without any examples, everyone agrees, and noone needs to think about what the media said or what happened at all. Everyone reading can be right and everyone else can be wrong at the same time.

Less snarkily - what media narrative are you referencing specifically? What do you believe occured instead? There was much media covering many angles on both of these issues.

[mattkrause]

I agree that they incorrectly predicted future events, but no one should be able to that with absolute certainty. Past events are, of course, much easier to report accurately.

[untog]

What does "got wrong" mean in this context, though? People said the media got those things wrong because they said "90% chance Clinton wins" and Trump won. But that's why they said 90%, not 100%. It feels as though the concept of probabilities is either misunderstood or willfully ignored to score points.

[jchallis]

In the initial formulation of the Gell-Mann effect, Michael Crichton noted that the coverage of show business was equally simplified.

From discussions with my wife, who is board certified in infectious diseases, newspaper coverage of the following topics are simplified to the point of losing the main point: antimicrobial resistance, any tropical disease from malaria to Ebola, organ rejection.

I think the problem is universal not specific.

[karmakaze]

Any decent news report will of course have coverage of the literal facts, this will also be overshadowed by interpretation of the meaning of those facts. Any dry reporting which only present the facts without a hint as to how the reader should be reacting to those facts is unpopular and will be read by negligible few. It starts right from the headline that takes a view one way or the other. A number isn't presented without an adjective.

[twic]

If someone asked me what i thought the main problem with comments on Hacker News was, i would direct them to this comment.

[strainer]

The blogged claim that Amazon "consumes about as much oxygen as it produces" is not sourced and the piece seems to fly in the face of professional work on the subject. eg: "The global oxygen budget and its future projection" [1]

> Fig. 4 summarizes the annual averaged global O2 budget from year 1990 to 2005, with the mass of O2 in gigatonnes (Gt) listed in each sink and for each process mentioned above (see Section 2.5). The inputs of O2 to the atmosphere by land and outgassing from oceans are quantified as 16.01 and 1.74 Gt/a, respectively. ....

[1] https://www.sciencedirect.com/science/article/pii/S209592731...

[BurningFrog]

Let's demystify how plants "produce oxygen".

They do it by splitting CO₂ molecules. The oxygen part (O₂) goes into the air, and the carbon (C) part becomes the plant.

So for the Amazon to continually produce surplus oxygen to the atmosphere, it must also continually produce an ever expanding amount of plant material ("wood") that would form an ever growing pile there.

This is not happening. Because forests don't produce surplus oxygen. Our atmosphere doesn't work that way.

https://en.wikipedia.org/wiki/Photosynthesis

[EB66]

> This is not happening. Because forests don't produce surplus oxygen. Our atmosphere doesn't work that way.

This is just plain wrong. The blogger is completely wrong on this point as well.

In normal atmosphere conditions, photosynthesis does result in net oxygen gain. Plants do require oxygen for respiration, but they require far less oxygen than what they produce during photosynthesis. Furthermore, at night when there's no light, plants do absorb oxygen and give off carbon dioxide in order to continue respiration -- but the amount of oxygen given off during the day is typically ten times greater than the quantity of oxygen consumed at night.

> This reminds me, as we should all be reminded on a regular basis, the bulk of the things you read in the popular press are at best skimming the surface and at worst outright misleading due to grabbing onto one obscuring factoid instead of the most important pieces of information.

Similarly, we should all be reminded that when skimming blogs and comments you're likely to come across misleading and inaccurate content. Scientifically inaccurate content like this gets posted on HN and blindly upvoted all the time.

[shkkmo]

> The blogger is completely wrong on this point as well.

I think you may not have read the article closely enough:

>> Plants produce oxygen through photosynthesis (green arrow). However, the the same plants consume the equivalent of over half the oxygen they produce in their own respiration ... my own team's research suggests this is more like 60%

>> The remaining 40% of the Amazon oxygen budget is consumed mainly by microbes breaking down the dead leaves and wood of the rainforest, a natural process called heterotrophic respiration

> Similarly, we should all be reminded that when skimming blogs and comments you're likely to come across misleading and inaccurate content

The "blogger" who wrote this article is "Professor of Ecosystem Science, University of Oxford" and "Founding Director, Oxford Centre for Tropical Forests" and probably knows more about this than you or I. This is not a peer reviewed paper, but it is probably more accurate than science journalism by a non-ecologist on this topic.

[strainer]

> my own team's research suggests this is more like 60%

My point was he hasn't cited that research - if it is concluded ? published? reviewed?

He seems to be just having a technical rant about a contextual phrase while giving the impression that forests in general, or at least the amazon or equatorial forests do not help maintain the atmospheres oxygen content. That would certainly be a maveric proposition at this stage in Earth sciences.

[shkkmo]

> My point was he hasn't cited that research - if it is concluded ? published? reviewed?

I am far more willing to take the word of an established and respected expert who understand the subject mater than a random internet person with a poorly contextualized citation. You can find the author's published papers on this and related subjects quite easily at the top of the article.

> He seems to be just having a technical rant about a contextual phrase while giving the impression that forests in general, or at least the amazon or equatorial forests do not help maintain the atmospheres oxygen content. That would certainly be a maverick proposition at this stage in Earth sciences.

He is a scientist clarifying a technical subject that has been being misconstrued. There has already been plenty of damage done by people throwing around fake facts and pictures.

[EB66]

> I think you may not have read the article closely enough

I did read the article closely :)

>> Plants produce oxygen through photosynthesis (green arrow). However, the the same plants consume the equivalent of over half the oxygen they produce in their own respiration ... my own team's research suggests this is more like 60%

>> The remaining 40% of the Amazon oxygen budget is consumed mainly by microbes breaking down the dead leaves and wood of the rainforest, a natural process called heterotrophic respiration

The author is stating that the Amazon rainforest is in perfect equilibrium without citing any studies or evidence. There are plenty of studies that indicate otherwise, such as this 30 year survey involving 100 researchers: https://www.nature.com/articles/nature14283

> While this analysis confirms that Amazon forests have acted as a long-term net biomass sink, we find a long-term decreasing trend of carbon accumulation.

But even if we accept the author's argument that today the Amazon is in perfect equilibrium -- I think it was misleading of the author not to clarify that in order for any forest to grow, it must be a net carbon sink and net oxygen producer up to that point in the forest's lifetime.

Now the comment that I originally replied to said something different. That comment argued that forests cannot be net producers of oxygen because there aren't "ever growing [piles of wood]" and then he provided the Wikipedia article for photosynthesis as evidence supporting that. That's wrong as I explained above.

You can have forests that are net carbon sinks and net producers of oxygen and you don't need "ever growing [piles of wood]" in order for that to happen.

[shkkmo]

> The author is arguing that the Amazon rainforest is in perfect equilibrium without citing any studies or evidence

The author argued no such thing, You are making up claims adn attributing them to the author, so perhaps an even closer reading of the blog post would be beneficial.

>> So, in all practical terms, the net contribution of the Amazon ECOSYSTEM (not just the plants alone) to the world's oxygen is effectively zero. The same is pretty much true of any ecosystem on Earth, at least on the timescales that are relevant to humans (less than millions of years).

The paper you cited is talking about carbon dioxide, not oxygen. The net effect on global O2 levels of carbon sequestration is minimal and not significant on human time scales. That same carbon sequestration has a significant impact on global CO2 because there is much less CO2 in the atmosphere.

[shkkmo]

> The author is stating that the Amazon rainforest is in perfect equilibrium without citing any studies or evidence. There are plenty of studies that indicate otherwise, such as this 30 year survey involving 100 researchers: https://www.nature.com/articles/nature14283

Y. Malhi, one of the authors of that paper, is also the author of this blog post. That makes sense since he a preeminent rainforest ecologist who publishes lots of papers on the carbon cycle.

[BurningFrog]

A single plant does produce oxygen while it's alive, and the carbon is bound in its growing body.

But that carbon is all released back as it decomposes after its death.

On a "whole forest/whole year" perspective, there is normally an equal mass of plants growing and being decomposed, and thus the net oxygen effect is zero.

[EB66]

> But that carbon is all released back as it decomposes after its death.

> On a "whole forest/whole year" perspective, there is normally an equal mass of plants growing and being decomposed, and thus the net oxygen effect is zero.

Sure, if you're talking about a timespan of one hour, one month, one year, etc then it's definitely possible for biological processes in a forest to expel carbon in the form of CO2 in equal volumes that were sequestered by plants. You could even have an overpopulation of some kind of insect or fungus cause a forest to temporarily become a net contributor of atmospheric carbon.

But over the lifetime over the forest, the net effect is obviously massive CO2 sequestration and massive O2 production. If the net carbon impact was zero over the lifetime of a forest, then forests would have no soil. But we know that not to be the case. Forests grow, they accumulate soil, etc.

Despite constant heavy rains and erosion, soil in the Amazon rainforest is often several meters deep and spans an area of over 2 million square miles. That's a lot of carbon sequestration!

[BurningFrog]

I agree that for a "startup" forest, there will be an accumulation of soil.

I assume it reaches an equilibrium after some time, and that the Amazon soil has remained the same "several meters" deep for many millions years.

But I'll admit I don't know that, and you may have a valid point. If real, this effect has to be quite small though.

[nearbuy]

Then where is the carbon going?

[EB66]

We're talking about oxygen production. Not carbon sequestration.

Regarding sequestration: the carbon goes into the trunk, branches, roots and leaves of the tree. Leaves fall off the tree, rot and become soil. The tree eventually dies, rots and becomes soil.

Some carbon will be given off by various decomposition processes, but the overall net effect is by far a carbon sink.

[nearbuy]

> We're talking about oxygen production. Not carbon sequestration.

BurningFrog said the carbon from CO2 goes into plants. Since plant matter isn't accumulating, carbon can't be accumulating, and therefore oxygen can't either. You replied, "This is just plain wrong".

So you're saying the part that is sequestered goes into the soil. That means some significant fraction of the 20 billion tonnes of carbon the Amazon photosynthesizes each year is turning in to soil. You're claiming the amount of soil increases by this amount each year, correct?

[atoav]

Into the plant? Btw. you can easily test this yourself in a closed glas sphere.

[PeterisP]

Exactly, it goes into the plant, and is then released as the plant decomposes - so in a stable rainforest, where the total plant mass isn't increasing, the new plants growing (creating O2 and absorbing CO2) is fully balanced by old plants decomposing or burning (absorbing O2 and creating CO2); so there's no net creation of O2.

[nearbuy]

I meant overall in the long term, in response to EB66 saying BurningFrog is wrong.

The plants can't be net collecting carbon each year unless the Amazon contains more and more plant matter each year.

[strainer]

Into the amazon river and out to sea basically. Rain will wash a lot of matter that way.

[strainer]

If forests did not then some other body of plant mass would have to - erosion and weathering of rocks takes a lot of oxygen out of the atmosphere, and this needs replaced by biology by photosynthesis. In the long term this is the reason the Earth needs to "breathe", and plants are how it has done so. Plants die and are eaten by ranging animals, dispersing their material, creating soils and eventually sediments. This is a long cycle through which carbon is returned to ground, sometimes to metamorphic rock.

It takes place at a lower intensity than our burning of fossil material and forests in recent history. Regrowing forest, usefully captures carbon and releases oxygen more rapidly than mature forest, but of course not rapidly enough to make up for burning them down.

[mirimir]

The paper that you cite is talking about small changes.

> Under the Representative Concentration Pathways (RCPs) RCP8.5 scenario, approximately 100Gt (gigatonnes) of O2 would be removed from the atmosphere per year until 2100, and the O2 concentration will decrease from its current level of 20.946% to 20.825%.

    2018  209460 ppm
    2100  208250 ppm

That's 15 ppm per year.

From Stolper et al. (2016) A Pleistocene ice core record of atmospheric O2 concentrations:[0]

> We present a record of Po2 reconstructed using O2/N2 ratios from ancient air trapped in ice. This record indicates that Po2 declined by 7 per mil (0.7%) over the past 800,000 years, requiring that O2 sinks were ~2% larger than sources.

That's 7000 ppm decrease over 800000 years, or 0.009 ppm per year. And so yes, atmospheric oxygen concentration is dropping lots faster now. But TFA's point that it's slow, and regulated by long-term processes, is still valid.

0) https://science.sciencemag.org/content/353/6306/1427

[strainer]

So that's where he is getting the context for his rant >>

"So, in all practical terms, the net contribution of the Amazon ECOSYSTEM (not just the plants alone) to the world's oxygen is effectively zero."

Practically, the reason why we have oxygen in the atmosphere is plant photosynthesis over long terms. We can quibble over the net annual product of every forest and ecosystem as he has - but over geological timeframes, the plant life they contain is the reason we have any oxygen to breath. And if the amazon currently amounts to about 20% of the plant life on earth now, its not wrong to teach that it is doing 20% of the oxygen maintaining.

The fact that long term maintenance is obscured by shorter term dynamics including our modern industrial activity, does not make a lie of the understanding and respect that forests are lungs of the planet.

[eveningcoffee]

I am lately thinking that we are assigning too less value to this fact. We all need oxygen and we should have enough forests to produce it and this means that we should globally subsidize forest keeping. It is not a single country problem. It is a global problem.

[nearbuy]

1. The article explained this isn't true. Carbon dioxide is a problem. Oxygen depletion is not. Burning enough forests to decrease atmospheric oxygen by just 1% would increase CO2 by 5000%. We'd be dead long before we ran out of oxygen.

2. I'm not sure what you have in mind for "short term" vs "long term", but oxygen levels only change significantly over hundreds of millions of years.

3. Just like a stable sized forest doesn't produce any significant net oxygen, humans don't overall use up oxygen from breathing. The plants you eat (or if you're eating meat, the plants your food ate) released oxygen into the air when forming the carbohydrates and fats you eat. Your body then recombines these with an equal amount of oxygen to produce energy.

[eveningcoffee]

Of course excess CO2 is greater problem than lack of oxygen but these things are in 1 to 1 correlation - you need oxygen to burn carbon. The more you burn carbon the more oxygen you join from the environment. To get the same oxygen back you need to breakup all the carbon you burnt.

If you destroy the forest then you will reduce the capacity to remove the CO2 from the atmosphere and produce oxygen or do you disagree with this?

[shkkmo]

> over geological timeframes, the plant life they contain is the reason we have any oxygen to breath

About 1/2 of the oxygen produced is produced by Phytoplankton, which are not plants (though they are similar).

> And if the amazon currently amounts to about 20% of the plant life on earth now

The amazon accounts 16% of the photosynthesis on land.

> its not wrong to teach that it is doing 20% of the oxygen maintaining.

It is wrong. If you want to provide a nice round, reasonably accurate number you should use 10%.

> does not make a lie of the understanding and respect that forests are lungs of the planet.

Forests are important and and a significant part of the respiration of them planet, but they are less important than our oceans. Our oceans are the true lungs of the planet (edit: and they are not in great shape, atmospheric oxygen may not be an issue, but oxygenation of the ocean is more variable).

[mirimir]

Sure. But long term, the Sahara may green, and "replace" the Amazon. At this point, I'd worry more about the oceans.

[strainer]

Burning the amazon down is something to worry about. Not afforesting widely and extracting timber from the amazon ecologically so it sequesters carbon and supplies materials replacing demand for carbon intense alternatives - is tragedy.

The advice that amazons contribution is "zero", hedged under this safety-net word "effectively" is false to the understanding of geophysics and natural history. I hope the professor will clarify his language after consideration.

[mirimir]

I'm not arguing that it's not something to worry about. It certainly is something to be worrying about. But so are the tropical forests of Southeast Asia, which are arguably even more threatened.

But we should be worried about it because of the impact on global biodiversity. Not because we'll be running out of oxygen. Having ~20% oxygen in the atmosphere reflects a long-term equilibrium of biologic and non-biologic processes.

If advocates focus on the oxygen issue, adversaries can easily point to negligible changes, and argue that there's nothing to worry about.

And, as I said, to the extent that oxygen is an issue, we ought to worry even more about the oceans. They are by far the major oxygen source, and arguably more vulnerable to catastrophic collapse.

[shkkmo]

> the piece seems to fly in the face of professional work on the subject.

The blogger does professional work on the subject. The article makes it pretty clear that the net positive production of oxygen the the Amazon is so close to zero that it is only relevant on the time scale of millions of years.

[james_s_tayler]

One Strange Rock documentary on Netflix makes the same claim.

[smadge]

I think the charitable interpretation of the use of the “20% of the earths oxygen” statistic (as the article states this is probably more like 9% of earths photosynthesis) is not about an imagined fear of oxygen depletion, but drawing attention to how massive and important an ecosystem the Amazon is.

[luckylion]

That's likely, but we could pretend it's 80% with the same reasoning - and it has an even larger effect with regard to drawing attention to the importance.

[smadge]

I am not excusing the statistic. I think people should be accurate. To me the correct statistic is just as compellingly.

[bad_user]

Netflix has a pretty cool series called "One Strange Rock". You should watch it, they explain the Amazon's role well in one episode.

First of all oxygen is constant. Oxygen is currently not the problem. And it's a good thing that it's constant because we don't want more of it either.

The problem with Amazon is that on Earth it's all interconnected and while there's plenty of room for failure, there is a tipping point, scientists have only disagreed on where that tipping point is. Once we are there however we will no longer be able to stop the chain reaction.

[Retric]

There is no single tipping point. There are a vast number of different tipping points with different outcomes.

[BurningFrog]

There is this idea that the ecological balance is very fragile and easily destroyed.

This is true, in a way, but it doesn't mean nature will dies. It almost always just means that nature will find a new ecological balance.

[bad_user]

If nature finds a new ecological balance that's incompatible with human life, does it matter?

[BurningFrog]

This is more a Hollywood movie plot than something that really happens.

[zaroth]

Which is to say, there is no tipping point?

[Retric]

More that many systems are involved, and they are not all binary choices. So, local flooding for example does not operate on the same scale as ocean acidification.

[dmix]

So you see it being like the singularity that people predicted in tech/AI but for natural disasters?

[amelius]

> a bigger point that is often missed is that the Amazon consumes about as much oxygen as it produces.

Especially when on fire ...

[wodenokoto]

Consumes as much as it produces ... does that mean the animal life in the amazon consumes all the O2 produces by the plants, or does it mean that the life-cycle of any one tree consumes as much O2 when decomposing, as it produces during its time photosynthesizing?

If it is the latter, then we will see decreased oxygen levels as the forest decreases is size.

[_8j50]

"...consumes about as much oxygen as it produces."

If it burns,there will be leftover life that will no longer be supported by the amazon. Causing a significant increase in net Oxygen consumption.

1% uncomoemsated consumption doesn't sound like much but it will remain that way or worse whic means total O2 will continue to deplete.

[empath75]

Not for very long.

[mrpopo]

They burn the amazon to leave way for cattle. The abounding biodiversity there will be replaced by cows for mass consumption. His point holds.

[MuffinFlavored]

> Second, a bigger point that is often missed is that the Amazon consumes about as much oxygen as it produces."

Does this mean that if the Amazon rainforest fell off of the map tomorrow, life as we know it would pretty much stay the same/be ok?

[ctrl-j]

I mean.. I get your point.. but 9% is still a lot, and even if it's net-zero, the carbon sequestration going into that process can't be negligible.

It may be a click-bait factoid, but it's not like that factoid isn't an important one.

[Misdicorl]

As a follow up to my above, it's the weight of the forest that matters. Older forests typically fit bigger and denser and heavier trees, so the age of a forest still matters a lot. But a fairly established forest like the Amazon is not changing the amount of oxygen out carbon dioxide in the air unless it's expanding or contracting

[Misdicorl]

There is no active sequestration for a static forest. Only if the forest is expanding in size will sequestration occur. Obviously reducing the size via burning has the opposite effect

[cm2187]

But doesn't it regrow from the hashes?

[marvin]

From the ashes? Not if it's turned into a ranch!

And I'm not qualified to answer what happens when you burn down an entire millenia-old ecosystem. Seems plausible that it might not go straight back to its old self in a human-relevant timeframe.

[didbsivdf]

“Not if it's turned into a ranch!”

That’s not obvious to me. Most plants are C2 plants, but grass is a C4 so it captures sunlight more efficiently.

Not to say burning the Amazon isn’t a terrible idea.

[Armisael16]

Plants pretty consistently are ~40-50% carbon by mass, so the amount of biomass on the ground is a fairly solid indicator of the amount of carbon sequestered. Unless the ranchers have a truly massive amount of hay at all times I don't see how a ranch can approach a forest.

[cm2187]

Well my question is rather if it becomes a growing forest again, ie capturing co2.

[Misdicorl]

Eventually. See my other comment

[ngold]

So yes or no does the amazon provide 20% or not?

[shkkmo]

TLDR: The amazon produces 9% and consumes 9%. We have ~500x more oxygen than CO2 so any disparities will be seen in global CO2 levels WAY before global O2 levels.

[molteanu]

This is just another political play to oust Bolsonaro, the Brazil's president, from power. There have already been EU voices pushing for sanctions against Brazil and the Amazon fires are on the G7 agenda which brings a lot of negative press against the political body in Brazil. All the while central Africa is also ravaged by fires but you don't hear that in the news.

Like most of what you hear in the big press, it comes with an agenda. It's not the case that a 'zero' was mispelled or enough info was not available, thus the erroneous reporting. You won't win the argument that way. The piece simply has another purpose from the one it is claiming to have, in this case, that future generations will say that the fires wiped out the entire human civilization in all it's glory at the hand of the Brazilian president. Ergo, he has to go until it's not too late.