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Related: About this forumGlobal human-made mass exceeds all living biomass
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The paper I'll discuss in this post is this one: Global human-made mass exceeds all living biomass (Emily Elhacham, Liad Ben-Uri, Jonathan Grozovski, Yinon M. Bar-On & Ron Milo, Nature volume 588, pages 442444 (2020))
The current rate at which we are dumping the dangerous fossil fuel waste carbon dioxide into the atmosphere amounts to roughly 35 billion metric tons a year, this while we all wait with child like anticipation for the grand so called "renewable energy" nirvana that did not come, is not here, and will not come. This is the highest rate ever recorded, and is reflected by the fact that increases in the concentration of this particular dangerous fossil fuel waste in the planetary atmosphere has risen to 2.4 ppm/year, after being 1.6 ppm/year as recently as the year 2000.
The irresponsibility of my generation, which surely will be condemned in history, has meant that the only option for restoration of the planetary atmosphere will involve the removal of carbon dioxide from the atmosphere, and I have spent no inconsiderable amount of time reflecting on the feasibility of this enormously challenging engineering task. In a purely thermodynamic sense, the fixation of carbon dioxide requires not only enthalpy, which may be thought of, somewhat naïvely, as putting the energy released by combustion of the carbon in carbon dioxide back into it, but also the entropy of mixing, the fact that while the carbon dioxide concentrations are rising, with the result of a profound physicochemical effects on heat exchange and acidity, they are still dilute. The 420 ppm we will likely see in 2021 while reaching unprecedented levels, still is only present as 0.042% of air.
This means that to obtain one kilogram of carbon dioxide at 100% extraction efficiency - which is not likely - one would need to process over 2,000 kg of air. Large amounts of air are processed by devices built by humans, but most of them, in fact the overwhelming majority of them, add carbon dioxide to the air since they are combustion devices. A jet engine is an example of such a device, a heat engine operating on the Brayton cycle, where the air is heated by the combustion of jet fuel in it.
(It does seem fairly obvious to me that Brayton cycle devices might operate without dangerous fossil fuels, but that's another subject.)
The situation is ameliorated to a limited extent by the fact that water, in particular seawater, acts as a liquid extractant for CO2, in equilibria with carbonates, as seawater is slightly basic, although less so than it was even 50 years, even 10 years, ago. The rate of change for the pH of the oceans is estimated to be about -0.002 pH units/year, which is not trivial, since pH is a logarithmic function. (cf. Climatological distributions of pH, pCO2, total CO2, alkalinity, and CaCO3 saturation in the global surface ocean, and temporal changes at selected locations (Taro Takahashi, S.C. Sutherland, D.W. Chipman, J.G. Goddard, Cheng Ho, Timothy Newberger, Colm Sweeney, D.R. Munro, Marine Chemistry 164 (2014) 95125)). Of the roughly 35 billion tons of carbon dioxide dumped each year, alleged - in complete opposition to something called "reality" - to be "transitional" by the complete fools who have bet the planetary atmosphere and the future of the biosphere on their reactionary enthusiasm for so called "renewable energy," about 26 billion tons of CO2 are absorbed by the ocean each year. (cf. Total alkalinity minus dissolved inorganic carbon as a proxy for deciphering ocean acidification mechanisms (Liang Xue, Wei-Jun Cai, Marine Chemistry 222 (2020) 103791)). This paper, citing Climatological distributions of pH, pCO2, total CO2, alkalinity, and CaCO3 saturation in the global surface ocean, and temporal changes at selected locations out of Columbia University, (Takahashi et al., Marine Chemistry 164 (2014) 95125), gives a working figure of 2061 ?mol/kg of total dissolved inorganic carbon. This figure translates to about 0.11% w/w dissolved organic carbon. This figure corresponds to seawater containing about 260 times as much carbon dioxide as does air on a weight basis. It is important to note that seawater is not homogenous, and the precise concentrations vary with conditions such as temperature gradients, pressure gradients, salinity gradients and many other factors connected with the properties of seawater. All of these parameters will have an effect on the chemistry and concentrations of dissolved inorganic carbon. A great deal of scientific literature has been equations of state for seawater, and international consortiums have worked diligently to address and formulate these. The current equation of state for seawater often utilized is TEOS-10 Just a single sample, among thousands upon thousands, of papers relating to either the measurement or modeling of seawater, this one about density is this one: (p,?,T) Properties of seawater at brackish salinities: Extensions to high temperatures and pressures (J. Safarov, S.Berndt, F.J.Millero, R.Feistel, A.Heintz, E.P.Hassel, Deep-Sea Research I 78( 2013) 95101) This interesting paper extends the equation of state for seawater into regions approaching the supercritical state, which in my view, represents the best path to recovering carbon dioxide, and many other valuable constituents, notably phosphorous, from seawater.)
The actual chemical form of dissolved inorganic chemistry depends heavily on pH, temperature, density and other thermophysical properties of seawater, but these forms are dominated by carbonate, bicarbonate, and CO2 clathrates. This figure from the Xue and Cai paper cited above, gives a feel for this issue:
The caption:
The laws of thermodynamics dictate that processes of this type are not actually reversible without putting more energy into a system than it put out. Thus the energy required to remove carbon dioxide from the air will be greater than the energy released putting it there, but the extraction of carbon dioxide by seawater will surely aid in improving the thermodynamic efficiency of any such effort. Thus future generations, attempting to do this will need not only to provide energy for their own use, but also produce all of the energy produced by previous generations in the profligate use of dangerous fossil fuels. As we prattle on with our "by 2050" and "by 2100" and "by 'such and such a year'" obscenities, placing the onus on people who are now infants, or future infants to do what we have been unable to do ourselves, this with depleted resources and a destroyed environment, it is important to keep this dolorous fact in the backs of our minds.
The reason that so called "renewable energy" has not worked, is not working and will not work to address climate change or save the planet, and why humanity abandoned it almost completely (except for, in most cases, among extremely impoverished people) in the 19th and early 20th century, is that it has a low energy to mass ratio. The conceit among people hyping the failed solar industry, for example (failure being defined as addressing climate change, and not the wasteful exchange of money and resources) is to state the energy to area flux of sunlight and then to act, stupidly, as if it is all there for the taking taking at no environmental or material cost. In addition to the 35 billion tons of carbon dioxide, according a lecture I attended a year or so ago by Dr. Robert Kopp, about 10 billion tons of carbon dioxide in addition to that dumped by the rising use of dangerous fossil fuels is attributable to land use changes. Ploughing access roads through pristine wilderness for diesel trucks to haul wind turbine parts around is not climate neutral. The material cost of manufacturing this temporary crap is also a factor.
All this said, this brings me to the relevant point, in terms of the paper cited at the outset, specifically, biomass. The combustion of biomass is responsible for slightly less than half of the 6 to 7 million air pollution deaths that take place each year, while anti-nukes carry on about so called "nuclear waste," which has a spectacular record of killing, if anyone, only a few people. (When you ask anti-nukes to report how many deaths are associated with the storage of used nuclear fuel, they generally start mumbling insipid nonsense about thousands, millions and even billions of years from now. They suffer from Trumpian type delusions.) Thus the death toll associated with this particular form of so called "renewable energy," at least as currently practiced, makes it the most dangerous of all of them, not that the others are risk free.
However, biomass has the property of being self-replicating, thus being able to cover vast surface areas without human intervention, or in spite of human intervention, which it historically it has, despite human efforts to minimize or destroy these surface areas. My contempt for solar energy fantasies notwithstanding, biomass, albeit at low thermodynamic efficiency, because of its ability to cover large surface areas, is capable of, and obviously is, a potentially very useful tool for the removal of carbon dioxide from the air, using only solar energy. Understanding this, I have spent quite a bit of time studying the chemistry, in particular, of cellulose and lignin derived products, such as furanoyl compounds, aromatic species, notably phenolic polymers, as these products can represent carbon that is sequestered in an economically viable, in fact, value added fashion. It is generally true that processes exploiting biomass need not be anywhere near as deadly as is currently observed, where the victims are largely the poorest citizens of the world, on whom the first world relies to produce endless piles of stuff in quasi-slavery or actual slavery settings.
Of course, the carbon released largely in the last two centuries by the combustion of dangerous fossil fuels represents many hundreds of millions of years of captured solar energy, and so it is not reasonable to expect that photosynthesis will instantaneously address the scale of carbon that needs to be captured, but this said, it is not wise to ignore the potential to do something. I would guess that humanity will still need industrial means, for example, raising the temperature of seawater to supercritical levels using nuclear heat, thus separating dissolved inorganic carbon, oxidizing microplastics to carbon dioxide and reducing water to hydrogen, that now pollute our oceans, and providing fresh water to fossil freshwater groundwater, dried lakes, and agricultural regions.
In order to evaluate the potential to do this, it is useful to note how much biomass there is, which is something the paper at the outset addresses, while noting that human "stuff" now outstrips the amount of biomass on the planet.
From the introduction to the paper:
A case in point is our planets biomass. While the mass of humans is only about 0.01% of global biomass, our civilization had already had a substantial and diverse impact on it by 3,000 years ago9. Since the first agricultural revolution, humanity has roughly halved the mass of plants, from approximately two teratonnes (Tt, units of 10^(12) tonne; where estimates are on a dry-mass basis) down to the current value10 of approximately 1 Tt. While modern agriculture utilizes an increasing land area for growing crops, the total mass of domesticated crops (about 0.01 Tt)11 is vastly outweighed by the loss of plant mass resulting from deforestation, forest management and other land-use changes10. These trends in global biomass have affected the carbon cycle and human health12,13. Additional human actions, including livestock husbandry, hunting and overfishing, have also strongly affected the masses of various other taxa11,14,15. A recent survey of Earths remaining living biomass11 has found that, on a mass basis, plants constitute the vast majority (about 90%)16, followed by bacteria, fungi, archaea, protists, and animals.
Beyond biomass, as the global effect of humanity accelerates, it is becoming ever more imperative to quantitatively assess and monitor the material flows of our socioeconomic system, also known as the socioeconomic metabolism17,18. This quantification is at the heart of the economy-wide material flow analysis framework, under the field of industrial ecology, which is based on mass balance accounting19,20...
There you have it. The total dry biomass of the planet represents about a trillion tons, only a portion of which is carbon. (Carbohydrates, which dominate biomass, contain only about 40% carbon by weight.) It can be shown, crudely assuming as a first approximation that all of this biomass is represented by carbonhydrates, that this corresponds to about 1.4 trillion tons of carbon dioxide, were all of the carbon in these putative carbohydrates oxidized. In other words, all of the biomass on the planet, every living thing, contains, assuming 30 billion tons of carbon dioxide dumping per year on average over the last century, about 50 years worth of dumped carbon. Of course, you, the readers, are biomass, and I'm fairly well convinced that you will not desire to be reduced to sequested carbon to serve the cause of addressing climate change, even if - this is true - climate change threatens your life in other ways.
Further on down, the paper does address the mass of humanity, and the animals raised by humanity along with some other commentary:
Some figures from the text:
Fig. 1: Biomass and anthropogenic mass estimates since the beginning of the twentieth century on a dry-mass basis.
The caption:
Our waste, how we love waste, counts too.
Fig. 2: Biomass (dry and wet), anthropogenic mass and anthropogenic mass waste estimates since the beginning of the twentieth century.
The caption:
Fig. 3: Contrasting key components of global biomass and anthropogenic mass in the year 2020 (dry-weight basis).
These figures speak for themselves.
From the conclusion of the paper's discussion section:
This study joins recent efforts to quantify and evaluate the scale and impact of human activities on our planet9,23,27,28. The impacts of these activities have been so abrupt and considerable that it has been proposed that the current geological epoch be renamed the Anthropocene29,30,31,32. Our study rigorously and quantitatively substantiates this proposal. In parallel, it adds another dimension to this discussiona symbolic quantitative demarcation of the transition to our epoch.
Don't worry, be happy. Wind turbines. Solar cells. Tesla electric cars, "freedom of the road." Batteries. Blah, blah, blah. It's not our problem, but the problem of those "by 2100" kids in the renewable energy nirvana we've declared for them, albeit with oblivious contempt for reality and, especially, for them.
I note that the history of our times will be written by them. As I often say:
I trust you will have a safe and happy New Year.
Pantagruel
(2,580 posts)Too vague!
I use the "We will be cursed by our gasping grandchildren" epithet, hoping to make it personal to the deniers.
Laelth
(32,017 posts)Thank you for this post.
-Laelth
NNadir
(33,512 posts)Laelth
(32,017 posts)It is rare too see such passion in mainstream science.
-Laelth
AZ8theist
(5,456 posts)If the population of humans occupying the planet could have been limited or controlled, none of this would have been a problem. Unfortunately, every effort at zero population growth in the 70's was stymied by RELIGION which equated every effort with promoting "abortion".
It was misguided and destructive, and typical religious anti-scientific. Fossil fuel burning for energy, over fishing, over grazing, cutting down the rain forest for more beef production, mining, short term money and profit......etc, etc...
Homo Sapiens will eventually become extinct. The fault is at the doorstep of religion. The planet will recover after humans are gone.
Pantagruel
(2,580 posts)Too many people ,not enough resources. Humans have been looking for safe population control methods for millennia. Come the 70's science provides safe birth control and abortion and the GOP decides to demonize the one virtually foolproof solution to so many problems like energy, disease and global hunger.
nam78_two
(14,529 posts)Last edited Mon Jan 4, 2021, 03:54 AM - Edit history (3)
People with large families should not feel demonized. People stop listening when they feel personally attacked.
But we need to delicately address the issue to reframe it when challenging ingrained views. Preaching to the choir is easy..It is persuading those who are antagonistic initially.
It should be framed as what it is- something which improves the prospective future of their own descendants. 1-2 or even 3 kids seems like a reasonable number. If you have more-it should take their welfare into account and it is only for those who genuinely like large families. I have met such people and they seem happy and importantly people like me who prefer to be child free balance them out. Homeostasis. There is no evolutionary race. We all win when we pull together. We evolve as a species when we have the ability to care about other people's progeny. Some of the people dearest to me are not biological relations.
Besides in the long run most lines die out:
https://www.chicagotribune.com/news/ct-xpm-1985-12-26-8503290655-story.html
My family line is entirely dying out (lots of educated people) mostly, but I have other contributions I can focus on-science, animal welfare etc.
Btw the covid 19 pandemic seems most likely the result of the wildlife trade. I will post more on the the pandemic and the wildlife trade after this volatile period is past.
https://www.sciencedaily.com/releases/2020/11/201117133918.htm