Archive for the ‘Burning Forests’ Category

EARTH OUT OF OXYGEN: 1) Basic Reasoning, Objection From Atmospheric Scientist

September 2, 2019

Yes, we can run out of oxygen. When they burned the Jews, nobody came: they were not Jews, after all, and had never heard of such a thing. Now they, the same suspects, superficiality, small-mindedness, greed, idiocy, ignorance, sheer viciousness, brutishness, and madness of the crowds, burn the planet’s atmosphere. Will somebody come?

This is an extension, an update, of what I already explained more than six years ago:

https://patriceayme.wordpress.com/2014/05/30/global-hypoxia/

My basic theory, in a nutshell: Increased heat and drought caused by the augmentation of CO2 launched a holocaust of primary forests, worldwide, that, in turn feeds the rise of acidity of the oceans, killing the phytoplankton. So yes, should CO2 keep on rising, the biosphere will run out of oxygen!

CAN WE RUN OUT OF OXYGEN? YES, OF COURSE! AS THE BIOSPHERE COLLAPSES, we don’t expect any less!

Philosophy is what happens when one thinks hard about the foundations. 

Civilization class philosophy is vastly superior to all the thinking done before, because before knowing (that’s called science), one has to guess what there is to know (finding out what is more significant in the morass of possible knowledge)

Foundation thinking often reveals we don’t know enough to have the deep foundations usually assumed. French President Macron went all out for the burning forests, in Siberia, Amazonia, Indonesia and Sub-Saharan Africa, burning to an extent never seen before, and I thank him for it. This unprecedented holocaust (holo-caust means all-burn in Greek) is one more step in the desertification caused by man. 

“Our house is burning. Literally. The Amazon rainforest – the lungs which produces 20% of our planet’s oxygen – is on fire,” Macron wrote in a tweetIt is an international crisis. Members of the G7 Summit, let’s discuss this emergency first order in two days!” UN Secretary General Antonio Guterres reinforced the oxygen message, August 22, 2019: I’m deeply concerned by the fires in the Amazon rainforest. In the midst of the global climate crisis, we cannot afford more damage to a major source of oxygen and biodiversity. The Amazon must be protected.”

However articles sprouted all over, from US scientists insisting in the world media that French president Macron got it wrong, and that, whatever we did, we will not run out of oxygen. My first reaction was that those scientists are either feeble minded, or liars: we can run out of oxygen, thanks to the likes of the Amazon burning. 

At first, such scientists reminded me of Nazi scientists claiming under the Third Reich that nothing wrong could possibly happen with Nazism, or with the Jews.

We have not thought hard enough about the foundations in the matter of climate.

Some US scientists have even claimed that forests, as a system, actually produce no oxygen. Here is below what Dr. Scott Denning, Professor of Atmospheric Science, Colorado State University says. Before I quote his entire article in The Conversation, let me point out that I do not disagree with the science he exposes, just his conclusion. This will be explained in my next essay, and Professor Denning’s kind answer:

Professor Scott Denning:

“Amazon fires are destructive, but they aren’t depleting Earth’s oxygen supply

26 août 2019

Fires in the Amazon rainforest have captured attention worldwide in recent days. Brazilian President Jair Bolsonaro, who took office in 2019, pledged in his campaign to reduce environmental protection and increase agricultural development in the Amazon, and he appears to have followed through on that promise.

The resurgence of forest clearing in the Amazon, which had decreased more than 80% following a peak in 2004, is alarming for many reasons. Tropical forests harbor many species of plants and animals found nowhere else. They are important refuges for indigenous people, and contain enormous stores of carbon as wood and other organic matter that would otherwise contribute to the climate crisis.

Some media accounts have suggested that fires in the Amazon also threaten the atmospheric oxygen that we breathe. French President Emmanuel Macron tweeted on Aug. 22 that “the Amazon rainforest – the lungs which produces 20% of our planet’s oxygen – is on fire.”

The oft-repeated claim that the Amazon rainforest produces 20% of our planet’s oxygen is based on a misunderstanding. In fact nearly all of Earth’s breathable oxygen originated in the oceans, and there is enough of it to last for millions of years. There are many reasons to be appalled by this year’s Amazon fires, but depleting Earth’s oxygen supply is not one of them.

Oxygen from plants

As an atmospheric scientist, much of my work focuses on exchanges of various gases between Earth’s surface and the atmosphere. Many elements, including oxygen, constantly cycle between land-based ecosystems, the oceans and the atmosphere in ways that can be measured and quantified.

Nearly all free oxygen in the air is produced by plants through photosynthesis. About one-third of land photosynthesis occurs in tropical forests, the largest of which is located in the Amazon Basin.

But virtually all of the oxygen produced by photosynthesis each year is consumed by living organisms and fires. Trees constantly shed dead leaves, twigs, roots and other litter, which feeds a rich ecosystem of organisms, mostly insects and microbes. The microbes consume oxygen in that process.

Forest plants produce lots of oxygen, and forest microbes consume a lot of oxygen. As a result, net production of oxygen by forests – and indeed, all land plants – is very close to zero.

There are four main reservoirs of oxygen on Earth: the terrestrial biosphere (green), marine biosphere (blue), lithosphere (Earth’s crust, brown), and atmosphere (grey). Colored arrows show fluxes between these reservoirs. Burial of organic material causes a net increase in atmospheric oxygen, and reactions with minerals in rocks cause a net decrease. Pengxiao Xu/Wikimedia, CC BY-SA

Oxygen production in the oceans

For oxygen to accumulate in the air, some of the organic matter that plants produce through photosynthesis must be removed from circulation before it can be consumed. Usually this happens when it is rapidly buried in places without oxygen – most commonly in deep sea mud, under waters that have already been depleted of oxygen.

This happens in areas of the ocean where high levels of nutrients fertilize large blooms of algae. Dead algae and other detritus sink into dark waters, where microbes feed on it. Like their counterparts on land, they consume oxygen to do this, depleting it from the water around them.

Below depths where microbes have stripped waters of oxygen, leftover organic matter falls to the ocean floor and is buried there. Oxygen that the algae produced at the surface as it grew remains in the air because it is not consumed by decomposers.

Tiny phytoplankton in the ocean generate half of the oxygen produced on Earth.

This buried plant matter at the bottom of the ocean is the source of oil and gas. A smaller amount of plant matter gets buried in oxygen-free conditions on land, mostly in peat bogs where the water table prevents microbial decomposition. This is the source material for coal.

Only a tiny fraction – perhaps 0.0001% – of global photosynthesis is diverted by burial in this way, and thus adds to atmospheric oxygen. But over millions of years, the residual oxygen left by this tiny imbalance between growth and decomposition has accumulated to form the reservoir of breathable oxygen on which all animal life depends. It has hovered around 21% of the volume of the atmosphere for millions of years.

Some of this oxygen returns to the planet’s surface through chemical reactions with metals, sulfur and other compounds in Earth’s crust. For example, when iron is exposed to air in the presence of water, it reacts with oxygen in the air to form iron oxide, a compound commonly known as rust. This process, which is called oxidation, helps regulate oxygen levels in the atmosphere.

Don’t hold your breath

Even though plant photosynthesis is ultimately responsible for breathable oxygen, only a vanishingly tiny fraction of that plant growth actually adds to the store of oxygen in the air. Even if all organic matter on Earth were burned at once, less than 1% of the world’s oxygen would be consumed.

In sum, Brazil’s reversal on protecting the Amazon does not meaningfully threaten atmospheric oxygen. Even a huge increase in forest fires would produce changes in oxygen that are difficult to measure. There’s enough oxygen in the air to last for millions of years, and the amount is set by geology rather than land use. The fact that this upsurge in deforestation threatens some of the most biodiverse and carbon-rich landscapes on Earth is reason enough to oppose it.

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[I beg to differ: actually I have a master reason to believe we do NOT have “millions of years” of oxygen (next essay). Hint: permafrost!]

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Well, thanks, professor Denning (from the prestigious U of C at Boulder. That university got several Nobels in physics, is located next to the delightful Flatiron/Green Mountain park, where I have climbed and unwittingly charged a very large mountain lion which was stalking (long story). I was actually going to NCAR (National Center for Atmospheric Research) when that happened… My spouse was doing there hard core programming on Sun Atmospherics. All this to say Denning is coming from what maybe the most qualified place in atmospheric matters!

However, as I will explain in the next essay, the very science professor Denning unfolded above leads me to the opposite conclusion from the one he draws.

Another point, see P/S below: up to very recently, it was viewed that forests (now burning) produced HALF of the planet’s oxygen. Professor Denning says: not so (well, OK, he is the specialist, he should know better… but I am curious to see the science…) In particular, up to very recently, the scientific literature widely quoted the Amazon as producing 20% of the world oxygen. It’s only very recently that US scientists (not just professor Denning!) changed their music. Is it that they heard that they better change their tune, should they want to be financed some more by the Trump administration, the fossil fuel plutocracy, or its delegates, surrogates and agents? Anyway, the P/S below shows what used to be the official science…

Another point is that an easy computation shows the atmosphere contains around 10^15 tons of oxygen. So some anti-Macron, and anti-panic about oxygen have argued we have millions of years of oxygen to consume, even if production stops. As I will show in the next essay, not so! Indeed, that simplicity overlooks an entire dimension. It may be frozen, but it’s all the more potent as it will come alive, all putrescent, rotting and belching all over: permafrost. 2.5 million years of it, no less! Glaciations may have help foster humanity, by creating new, exotic and demanding ecological niches which favored greater intelligence. By receding now, ice and climate change will require more creativity than ever… And better science.

Patrice Ayme

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P/S:

The following tables offer estimates of oxygen cycle reservoir capacities and fluxes… before the latest science professor Denning says is true…. Latest science which basically says it’s OK to destroy the forests, as far as oxygen production is concerned!!!!!!!!!!! (I don’t believe it, and I have a counter-reasoning, destroying professor Denning conclusion above… with his own logic!) These numbers below were taken for granted until very recently, and are based primarily on estimates from Walker, J. C. G.:[10]… 

Such numbers below were what Macron and Gutierrez based their O2 claims on…

Reservoir Capacity

(kg O2)

Flux in/out

(kg O2 per year)

Residence time

(years)

Atmosphere 1.4×1018 3×1014 4500
Biosphere 1.6×1016 3×1014 50
Lithosphere 2.9×1020 6×1011 500000000

 

Table 2: Annual gain and loss of atmospheric oxygen (Units of 1010 kg O2 per year)[1]

Photosynthesis (land)

Photosynthesis (ocean)

Photolysis of N2O

Photolysis of H2O

16,500

13,500

1.3

0.03

Total gains ~ 30,000
Losses – respiration and decay
Aerobic respiration

Microbial oxidation

Combustion of fossil fuel (anthropogenic)

Photochemical oxidation

Fixation of N2 by lightning

Fixation of N2 by industry (anthropogenic)

Oxidation of volcanic gases

23,000

5,100

1,200

600

12

10

5

Losses – weathering
Chemical weathering

Surface reaction of O3

50

12

Total losses ~ 30,000

Hint on the hidden O2 catastrophe: The mass of the biosphere: of the order of 4x(10^12) tons. Prof Denning says it can absorb all O2. OK. Indeed, notice microbial oxidation.

Suppose it all dies.

Not enough? Well, think a bit about all what got frozen during the last 2.5 million years of glaciation: the bill is coming due…

PA