[strainer]

The problem is I feel that he has confused understanding of the subject here rather than clarifying it, which is an easy thing for anybody to do in a conversational article.

Here is a recent work[1] which substantiates matters that Amazons practical involvement in the planets atmospheric oxygen/carbon levels is really not as the professor felt like putting it as "effectively zero".

> Abstract: The response of the Earth’s land surface to increasing levels of atmospheric CO2 and a changing climate provide important feedbacks on future greenhouse warming6,7. One of the largest ecosystem carbon pools on Earth is the Amazon forest, storing around 150–200 Pg C in living biomass and soils8. Earlier studies based on forest inventories in the Amazon Basin showed the tropical forest here to be acting as a strong carbon sink with an estimated annual uptake of 0.42–0.65 Pg C yr−1 for 1990–2007, around 25% of the residual terrestrial carbon sink3,4. There is, however, substantial uncertainty as to how the Amazon forest will respond to future climatic and atmospheric composition changes. .... Here we analyse the longest and largest spatially distributed time series of forest dynamics for tropical South America. .... Our data show that mature forests continued to act as a biomass sink from 1983 to 2011.5, but also reveal a long-term decline in the net rate of biomass increase throughout the census period. The decline in net biomass change is due to a strong long-term increase in mortality rates, and occurred despite a long-term increase in productivity. While mortality increased throughout the period, productivity increases have recently stalled showing no significant trend since 2000. ....

[1]https://www.nature.com/articles/nature14283

Published in Nature: 18 March 2015 : "Long-term decline of the Amazon carbon sink"

[EB66]

> The problem is I feel that he has confused understanding of the subject here rather than clarifying it, which is an easy thing for anybody to do in a conversational article.

I couldn't agree more. A bunch of people are coming away from reading that article believing that forests have no impact on global carbon sequestration and oxygen production. In attempting to make a contrarian technical point and refute mass media figures, the author has done a disservice to furthering public understanding of the issue.

Sure, a mature forest can come into equilibrium with regard to carbon/oxygen production and consumption. A forest could even be a net contributor of atmospheric carbon by means of an insect or fungus overpopulation. However:

1. Studies show that's not true for the Amazon rainforest (annually it is still a carbon sink).

2. Over the lifetime of the forest the effect is clearly a massive gain in oxygen and massive sequestration of carbon as evidenced by all the biomass (e.g., trees) and dirt you find in forests.

[shkkmo]

> A bunch of people are coming away from reading that article believing that forests have no impact on global carbon sequestration and oxygen production.

If you were really concerned about people misunderstanding the article, you would not make up claims and attribute them to the author. Instead you would quote the relevant parts of the article to demonstrate what is actually being said.

The author in no way claims that the Amazon is in equilibrium, (probably because as one of the foremost global experts on rainforest carbon cycles, he knows it isn't.)

Edit:

The claims are quite specific:

1) The amazon provides ~9% of the global O2 production.

2) The amazon consumes most of the O2 it produces through tree metabolism and wood decomposition.

3) There is way, way more O2 in the atmosphere than CO2 so the effects all human activity (or ecosystems) on global O2 levels are miniscule compared to their effect on global CO2 levels.

Burning down the entire amazon rainforest would be a bad for a number of reasons (release of CO2, changes in global weather patterns, loss of bio-diversity, etc), but impact on global atmospheric O2 levels is NOT one of those reasons.

Fear mongering about a non-issue with made up facts only serves to provide ammunition to anti-science skeptics.

[EB66]

> If you were really concerned about people misunderstanding the article, you would not make up claims and attribute them to the author. Instead you would quote the relevant parts of the article to demonstrate what is actually being said.

What on Earth are you referring to?

> The author in no way claims that the Amazon is in equilibrium

Yes he does. As I already explained to you, the author asserts that the O2 produced by the Amazon rainforest ecosystem is equal to the amount of O2 consumed by the Amazon rainforest ecosystem -- that is a perfect example of what it means to be in equilibrium. He literally says it in big bold letters:

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

Did he use the word equilibrium? No. Did he describe an equilibrium? Yes!

I am done arguing with you on this point -- it has truly devolved into semantics and has become unnecessarily inflammatory. At this point all I can do is refer you to a dictionary.

> Fear mongering about a non-issue with made up facts only serves to provide ammunition to anti-science skeptics.

Fear mongering? Now you've truly lost me. If asserting that forests net sequester carbon and produce O2 makes me a fear monger, then I'm guilty as charged...

[shkkmo]

> At this point all I can do is refer you to a dictionary.

The paper you cited as "disproving" the author's argument for "prefect equilibrium" was co-authored by the author.

Indeed, in the comments on the article, the author explains further:

>> [net carbon sequestration] is not related to the total amount of photosynthesis, but to where organic matter is being buried and removed from atmosphere and biosphere. This occurs in places like swamps, peat bogs and in particular deep ocean sediments. Material from the Amazon probably plays some role in this (e.g. organic material being swept out into the ocean and being buried in deep sediment), but this process is not strongly related to the amount of photosynthesis in any given area. I suspect the burial of a tiny fraction ocean plankton in deep sediments play a dominant role here.

> Fear mongering? Now you've truly lost me. If asserting that forests net sequester carbon and produce O2 makes me a fear monger, then I'm guilty as charged...

Sorry, I am talking about making claims like "the amazon produces 20% of our oxygen." and I was doing so to justify what you called "nitpicking"

The point I was trying to make (and clearly did a poor job with) is summarized by the author in one of his responses to attacks like yours and strainers:

>> No ecosystem scientist I have spoken disagrees with the science in this post: it simply highlights a long-established scientific understanding that oxygen angle is a myth. Just like no serious climate scientist denies the seriousness and importance of human-caused made climate change. If you choose to be selective about which science to choose to hear you fall into the same trap as the climate deniers, construct your own alternative facts universe and you betray your scientific training. The also open yourself the other, more accurate arguments being discredited as a package when the scientific truth emerges

[shkkmo]

What does that article show? Can you explain how that has any relavance to the impact on global oxygen levels?

Why are you still conflating O2 and CO2?

Edit: You do realize that "Y. Malhi", one of that authors of that paper, is the same "YADVINDER MALHI" who wrote this blog post.

[strainer]

> Why are you still conflating O2 and CO2?

That should be obvious. Any evidence of amazon sequestering carbon is evidence of amazon liberating oxygen. If you cant bear that in mind you have been distracted by the artificial separation proposed here, between "a strong carbon sink" sinking carbon and the respiring of O2, they are very effectively both expressions of the same process.

> one of that authors of that paper, is the same "YADVINDER MALHI" who wrote this blog post

Correct and it puts into stark contrast the co-authors private blog advice that "the net contribution of the Amazon ECOSYSTEM (authors emphasis) to the world's oxygen is effectively zero". That misjudged statement which is even highlighted in the article now, is in plain contradiction to that paper he took part in, which is also about the Amazon ECOSYSTEM and the Amazon can not physically be "a strong carbon sink" and at the same time have zero contribution to the worlds atmospheric oxygen system.

The claim is wrong, and hangs only on the ambiguities of what "effectively zero" could be argued to mean that is in reality documented to be very far from zero indeed.

The Amazon has been known for decades as great "lung" of the planet, SINKING Carbon and RELEASING O2. Malhi has himself taken part in work which describes it "greatly" doing so. If its personal credentials you put faith in you could regard Sir David Attenboroughs describing it the same, for many years, in finished and award winning works, as opposed to a professors conversational web article.

Malhi's advisory 9% figure (that is then subsequently reduced to zero?!) is not even necessarily more final or uncontestable as the supposedly terrible global media outbreak of 20% reports. And since (even that work Mahli took part in reveals) that the amazon is recently in serious flux, such figures are technically speaking conditional.

The point of publicity figure is to be defensible and educate the fact that the Amazon has had and can have major effects on the atmospheres important constituents. That whether it is currently in equilibrium or a great carbon sink or grave carbon emitter - is a very grave matter because by its size and history it is capable of all those things.

[shkkmo]

> they are very effectively both expressions of the same process.

But the effects on global atmospheric composition are not equivalent as has already been explained to you. The fact that you seem to choose to deliberately not understand this does not speak well of you.

> The claim is wrong, and hangs only on the ambiguities of what "effectively zero" could be argued to mean that is in reality documented to be very far from zero indeed.

There are no ambiguities, the caveats of that statement are quite clearly stated in the article.

> Malhi's advisory 9% figure (that is then subsequently reduced to zero?!) is not even necessarily more final or uncontestable as the supposedly terrible global media outbreak of 20% reports.

Nobody ever said it was final or uncontestable (that's not how science works). It is a fairly rough estimation, but even as such it is FAR more accurate and its precision is sufficient for popular discussion.

> The point of publicity figure is to be defensible and educate the fact that the Amazon has had and can have major effects on the atmospheres important constituents. That whether it is currently in equilibrium or a great carbon sink or grave carbon emitter - is a very grave matter because by its size and history it is capable of all those things.

Neither I nor the author dispute the importance of the amazon. What is disputed is the bad science that is being spread by the well-intentioned but misinformed.

Atmospheric O2 levels are not a problem, atmospheric CO2 levels are.

What do you think you are accomplishing by attacking environmental scientists and spreading misinformation? Are you really trying to help spread accurate knowledge about climate change? How does this help with that?

[strainer]

Please I have not attacked the professor at all. I have "attacked" an article which has you calling a statement which in all likelihood originates from the advice of an earth scientist > "bad science" and "mis-information" and has you defending the claim that the amazon ecosystems contribution to atmospheric oxygen "effectively zero" And that practically extends to co2 - any caveats are in fact in contradiction to the professors advice that fires and organisms use up all the produced oxygen. But we've already gone through that and are talking past each other now.

[nec4b]

The blogs author is a co-author of the article you linked.