Guest essay by Ronald R. Cooke
Introduction
In high school and college I did reasonably well in the physical sciences: chemistry, physics and geology. From these studies one can learn that carbon (C) is an element, is widely available throughout our universe, is chemically active (which means many inorganic and organic compounds include carbon), is present in the atmosphere as carbon dioxide, is present in all natural fresh and ocean water, is a component of rocks (such as limestone), is a primary element of buried organic materials (including hydrocarbon deposits of oil, coal and natural gas), and is a very important element of the human body (about 18.5% of the elements in our body by mass). In fact, all life on this planet is based on hydrocarbon compounds which include carbon, hydrogen and oxygen.
By contrast, carbon dioxide (CO2) is a colorless, tasteless and odorless gas that occurs naturally everywhere in, on and above our planet. Carbon dioxide is not carbon, but it does include one carbon atom and two atoms of oxygen. Carbon dioxide occurs naturally in the atmosphere. Higher levels of CO2 encourage the growth of stronger and more abundant plants. All plant life (a form of organic matter) has been produced by the interaction of CO2 with energy received from the sun (sunlight + H2O + O2 + CO2 = photosynthesis). All oil, natural gas and coal are derived from buried organic matter which has been compressed and heated over millions of years.
We humans would not exist if there were no CO2 in the atmosphere. We either eat the results of photosynthesis directly (when we consume grains, fruits and vegetables), or indirectly (when we eat animals, birds and fish that have previously consumed plant life). The natural metabolism of the body produces CO2 as a byproduct which we (like all animals) exhale when we breath.
Thus it makes no sense to examine the carbon cycle (an element) when we are really interested in the carbon dioxide cycle (a gas); most specifically we want to know how CO2 is produced and consumed, as well as how much residual CO2 there is in the atmosphere. In the following graph we show the primary categories of how CO2 exchanged with the atmosphere. Down arrows represent a decrease in atmospheric CO2. Up arrows represent an increase in atmospheric CO2. The size of the arrow represents the relative importance of each category. The importance of each category as a percentage of global CO2 is shown by the accompanying table.
| Carbon Dioxide Cycle | ||
| Increase | ||
| CO2 | ||
| Levels * | ||
| Plant Respiration | 220 | 27.6% |
| Decay of life forms | 209 | 26.3% |
| Sea Surface | 330 | 41.5% |
| Human Caused | 37 | 4.6% |
| 797 | 100.0% | |
| Decrease | ||
| CO2 | ||
| Levels * | ||
| Photosynthesis | 440 | 55.6% |
| CO2 taken by soils | 6 | 0.8% |
| Sea Surface | 338 | 42.6% |
| Conversion of CO2 | 8 | 1.0% |
| 792 | 100.0% | |
| Human Caused CO2 | 4 | |
| As a % of total CO2 | 4.7% | |
| Annual net increase | 0.55% | |
| *Gt (Rounded) |
Increase Atmospheric CO2
Plant Respiration
A plant takes up water (H2O), carbon dioxide (CO2), oxygen (O2), and minerals through its roots. It also exchanges carbon dioxide, oxygen, and water with the atmosphere through its leaves and stem. It uses the energy of sunlight to convert these into sugars and starch through a process called photosynthesis. These are then used by the plant to increase its size and biological activity (growth of leaves, stems, roots, fruits, seeds, and so on). In so doing, excess plant energy is given off as heat (respiration).
A typical process is: 6CO2+6H2O+energy (from the sun) = C6H12O6+6O2 (sugars). Notice there are 18 oxygen atoms going into the process and only 12 are used up. In photosynthesis the 6 excess O2 gas is released into the atmosphere. The respiration process is C6H12O6+6O2 = 6CO2+6H2O + energy (some as heat). Respiration releases CO2 and water into the atmosphere (and soil). Photosynthesis is a primary source for the oxygen we humans breathe in order to stay alive.
Decay of Life Forms
Microbial decay (decomposition of matter) is a process that starts soon after a plant or animal dies. Organic material is broken down into basic elements. Decomposition always includes the release of CO2.
Plant decay includes water leaching which liberates soluble carbon compounds, including CO2. Smaller plants are largely decomposed by soil invertebrate fauna. The decomposition of larger plants (like trees) typically involves parasitic life-forms such as insects and fungi. Microbial colonization accelerates the attack on plant cells. In the last stages of decay, cellulose, hemicellulose, microbial products, and lignin are chemically altered by microbes.
We humans, along with other animals, begin to decay almost immediately after death. The tissues of the animal body are broken down by internal chemicals and enzymes. Bacteria invade the tissues and start the process of putrefaction. Gases, including CO2, are released by decaying animal tissue.
Sea Surface
Although we do not have sufficient knowledge to establish all the dynamics of the CO2 gas exchange between the surface of the ocean and the surrounding atmosphere, it is estimated that slightly more CO2 is absorbed by the ocean than is released by the ocean surface into the air. It is both a physical and a chemical process that is primarily controlled by the differential between the concentrations of CO2 dissolved in the water and how much CO2 is available in the surrounding atmosphere. Since CO2 is soluble in water, we get the chemical equation CO2 + H2O = H2CO3, a weak form of carbonic acid. In the presence of free hydrogen H2CO3 + H = yields a bicarbonate ion which is stored within the waters of the ocean. The amount of CO2 which has been dissolved in the waters of the ocean varies with geographic location and the circulation patterns of the ocean currents. Higher concentrations are more likely to be found in the more populous and industrialized northern latitudes.
Human Caused
We humans release CO2 into the atmosphere when we breathe, raise animals, cut down trees, shrubs and grasses, burn peat and plants, consume fossil fuels, and so on. Our consumption of coal, oil and natural gas is by far the largest source of human caused CO2 because we consume large quantities of these fossil fuels by the process of combustion (burning). Gasoline, diesel, jet, and heavy fuels provide the energy that powers our transportation system, including personal vehicles. Natural gas, propane, heating oil, and kerosene heat our buildings and homes. Coal and natural gas are primary sources of the heat for the generation of electrical energy. As shown by the above table, we release about 4 billion tonnes of CO2 into the atmosphere each year; accounting for roughly 4.7 percent of all CO2 that is released into the atmosphere from all sources (natural and human caused). Because of human activity, total atmospheric CO2 is increasing bout .55 percent each year.
Decrease Atmospheric CO2
Photosynthesis
Plants consume far more CO2 through the process of photosynthesis than they release into the atmosphere through the process of respiration. These chemical reactions make plants green (usually), help them to grow stronger, and increase the rate of growth. For plants, more CO2 is better and there is some evidence that elevated levels of CO2 in the atmosphere have increased the greening of our planet. Plants, including trees, shrubs, grasses and crops, exchange CO2 with the atmosphere through their leaves and stems, and with the soils in which they live through their roots. At least 35 percent of available man-made C02 is consumed by plant life on our planet.
CO2 Taken by Soils
Since CO2 is soluble in water, damp or wet soils will take up CO2 where its chemical components may combine with other chemicals in the soil to produce other compounds.
Sea Surface
As discussed above, the ocean – along with lakes and rivers – removes more CO2 than is released into the atmosphere.
Conversion of CO2
Chemical conversion includes biological and chemical conversion of CO2 into other compounds, and effect of water vapor on CO2 in the atmosphere.
Results
Our model estimates that in 2015 we humans will cause the production of an estimated ~ 37 Gt of CO2. By way of comparison, the PBL Netherlands Assessment Agency has estimated in 2013 we humans were responsible for 35.3 Gt of CO2 from combustion of fossil fuels and industrial processes. It should be noted some scientists estimate human caused CO2 is significantly less than our estimate.
Human caused CO2 is ~ 4.7 % of total global CO2 emissions. This figure includes both combustion and non-combustion industrial processes (manufacture of plastics, fertilizers, paints, asphalt, cosmetics, etc.), agricultural land use changes, deforestation and logging, as well as CO2 from forest and peat fires.
The Annual Net Increase of global atmospheric CO2 is ~ .55% in our scenario for 2015. This percentage is approximately the same as the average annual mean of increased atmospheric carbon dioxide observed by NOAA ESRL at the Mauna Loa Observatory in Hawaii over the last 14 years ( ~ .54 % 2000 – 2014). A contraction of economic activity in future years will decrease man-made CO2 emissions.
As we have shown: chemical decomposition, photosynthesis, and absorption eventually remove man-made carbon dioxide from the atmosphere. It’s all a natural process.
TCE
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This is another attempt to provide my post that vanished. RSC
Ronald R. Cooke:
You say of your carbon cycle model
I draw attention to one of our 2005 papers
(ref. Rorsch A, Courtney RS & Thoenes D, ‘The Interaction of Climate Change and the Carbon Dioxide Cycle’ E&E v16no2 (2005) )
Our cited paper provides six models of the carbon cycle system. There are three basic models and they each assume a single mechanism dominates the cabon cycle system. In each basic model it is assumed that
1. the rise in atmospheric CO2 concentration is purely natural
and
2. there is a significant anthropogenic contribution to the rise in atmospheric CO2 concentration.
Thus we provided six models.
Each of the models in that paper matches the available empirical data without use of any ‘fiddle-factor’ such as the ‘5-year smoothing’ the UN Intergovernmental Panel on Climate Change (IPCC) uses to get its model (i.e. the Bern Model) to agree with the empirical data. For each year each of our models correctly predicts the atmospheric CO2 concentration measured at Mauna Loa to within the stated inherent error of the measurement.
The superior performance of each of our models over the IPCC’s Bern Model results from our modelling assumption. The Bern Model uses the assumption of anthropogenic CO2 emissions being in excess of what nature can sequester (which is now refuted by the OCO-2 data). Our models assume something has altered the equilibrium state of the carbon cycle system.
Some processes of the carbon cycle system are very slow with rate constants of years and decades. Hence, the system takes decades to fully adjust to a new equilibrium. The observed rise in atmospheric CO2 is easily modelled as being continuing slow adjustment towards an altered equilibrium.
This raises the question as to what may have altered the equilibrium of the carbon cycle.
One possibility is the anthropogenic CO2 emission. In our models the short term sequestration processes can easily adapt to sequester the anthropogenic emission in a year (which is now confirmed by the OCO-2 data). But, according to our models, the total emission of that year affects the equilibrium state of the entire system with resulting rise in atmospheric CO2 concentration as is observed. This possibility is real but unlikely.
Natural factors are more likely to have caused the alteration to the equilibrium of the carbon cycle system. Of these, the most likely cause is the centuries-long rise in global temperature which is recovery from the Little Ice Age.
As mentioned above, each of the models in our paper matches the available empirical data without use of any ‘fiddle-factor’. But if one of the six models of our paper is adopted then there is a 5:1 probability that the choice is wrong. And other models are probably also possible. Also our six models each give a different indication of future atmospheric CO2 concentration for the same future anthropogenic emission of carbon dioxide.
Data that fits all the possible causes is not evidence for the true cause. Data that only fits the true cause would be evidence of the true cause. But the above findings demonstrate that there is no data that only fits either an anthropogenic or a natural cause of the recent rise in atmospheric CO2 concentration. Hence, the only factual statements that can be made on the true cause of the recent rise in atmospheric CO2 concentration are
(a) the recent rise in atmospheric CO2 concentration may have an anthropogenic cause, or a natural cause, or some combination of anthropogenic and natural causes,
but
(b) there is no evidence that the recent rise in atmospheric CO2 concentration has a mostly anthropogenic cause or a mostly natural cause.
Hence, using the available data it cannot be known what if any effect altering the anthropogenic emission of CO2 will have on the future atmospheric CO2 concentration. This finding agrees with the statement in Chapter 2 from Working Group 3 in the IPCC’s Third Assessment Report (2001) that says; “no systematic analysis has published on the relationship between mitigation and baseline scenarios”.
Richard
Footnote
I gave a presentation of the findings of our cited paper at the first Heartland Climate Conference and this is a video of my provision of that presentation.
Richard, FYI, you tend to make very long and detailed posts, usually with many links. The wordpress SPAM filter attunes to that…especially with lots of links and lots of words.
AW:
Thankyou for that info.
However, I am not clear how I could have shortened e.g. the post in this case without losing necessary explanation.
Richard
Mods:
I have twice tried to make a post but it vanished both times.
Please look in the ‘bin’ and if the posts are there then please retrieve the first of them. If they are not there then please be so kind as to let me know so I can try to post it again.
Thanking you in advance for your trouble
Richard
How exactly have these gigantic masses been measured? Reference to the original source will do, thanks.
Or let me guess: there is none, because they are not measured at all. They are calculated from the CO2 measurements next to the most active volcanic region known. Then CO2 surplus is pinned on The Man, because the Earth was created perfect by Gaia. Amen. Did I get this right?
jaakko,
They are estimates, but not only based on CO2 measurements, also on isotopes (δ13C) and oxygen changes. CO2 fluxes between oceans and atmosphere are mostly a matter of solubility with temperature and a small parallel change in δ13C, while CO2 fluxes between atmosphere and vegetation give a huge, opposite change in δ13C and set O2 free or reverse…
Carbon isotopes? Limestone (CaCO3) e.g. in Seven Sisters is presumed to be the most common type of stone on Earth. Quite unlike granite, it erodes easily. Contact with water is enough, no active volcano is required. What’s the difference between carbon isotopes in CaCo3 and the evil lithospheric hydrocarbon?
The reason for my question: although precision of tritium measurements with liquid scintillation counting was satisfactory, accuracy was more problematic, because of difficulty to ascertain the tritium source. The measurements had to be done under controlled conditions for this reason. I’m looking forward to discovering how Catastrophic Anthropogenic Climate Apocalypse scientists measure the entire planet.
jaakko,
Many volcanic emissions are measured as CO2/SO2 ratio in the plume and as SO2 is more easy to measure, because not in a bulk with SO2 from other sources (as is the case for CO2), it is easier to calculate the CO2 emissions.
Further, most inorganic CO2 has a δ13C level around zero and even deep magma volcanoes (which don’t recycle CO2 from carbonate deposits) have δ13C levels above the atmosphere.
Thus any CO2 from the oceans, rock weathering,… would increase the δ13C in the atmosphere, while we see a firm decrease.
The fluxes between vegetation and atmosphere are positive for δ13C and O2 when CO2 is absorbed and negative when CO2 is released by burning, decay or digestion. In balance, the biosphere is a net sink for CO2. Thus not the cause of the CO2 increase or δ13C decline…
Sampling in the bulk of the atmosphere gives near-global levels for CO2, O2, CH4 and other well mixed gases, except for seasonal changes and continuous emissions, which need time to spread over the globe. Even these differences are within a few % of full scale…
See for some background:
http://science.sciencemag.org/content/287/5462/2467
and
http://www.bowdoin.edu/~mbattle/papers_posters_and_talks/BenderGBC2005.pdf
You forgot volcanoes.
And they are important for this main reason: change the ocean chemistry and you change the equilibrium between c02 within subsurface oceanic volcanic rocks (mostly carbonate) and c02 dissolved in the surrounding seawater. (Note volcanic activity-emitting c02 varies greatly over geological time, possibly causing mass extinctions, but this is not relevant to the current, more or less consistent volcanic output of c02).
If you think volcanoes don’t matter much, note that some scientists think nearly all the world’s water that formed the oceans came originally from solidifying magma, early in earth history (not comets). When magma cools, it expels water and c02. The interplay between volcanic rocks containing vast amounts of c02 mainly in the form of carbonate and the surrounding seawater is likely a major buffer to any changes in c02 within the ocean, meaning it is very likely that oceans do not change their ph much over time.
thingadonta:
You say
Yes! Please note that volcanoes release sulphur ions that affect the pH of sea water and are not affected by the carbonate buffer.
A change to the average sea surface pH of an unobservably small 0.1 would have altered the equilibrium between air and ocean surface to cause a change of atmospheric CO2 concentration greater than that claimed to have happened since the industrial revolution.
Richard
Richard,
The small pH change is only measurable in recent years in the surface, not in the deep oceans.
In theory, such a decrease in pH may come from deepsea volcanic SO2, but in that case, CO2 would be expelled and DIC (the sum of all inorganic carbon derivatives) in seawater would decrease. In this case the longer time series show an increase of DIC with decreasing pH. Thus CO2 enters the oceans from the atmosphere, not reverse.
See here for Bermuda:
http://www.biogeosciences.net/9/2509/2012/bg-9-2509-2012.pdf
Ferdinand Engelbeen:
Yes, as you say, the small pH change has only been capable of measurement recently so its change over decades and centuries is not known. Also, in the very few places where ocean pH been measured the daily variations are much greater than the putative change in average pH of 0.1.
Measurements of oceanic carbon contents are also too sparse for them to be meaningful.
Richard
Reference – the essay/blog writer – “The carbon dioxide cycle Please, people; don’t knock it! This was a basis for biology and such studies from over 60 years ago and is upheld in the basis of much more modern publications. The overall benefits of CO2 are well established, calcification within the oceans are well apparent (white cliffs wherever) and land recovery and recession affecting sea level readings are well established (Scotland inland rising, Kent (S.E.coastal) sinking.
Acidity more or less balanced, even beyond changes within 24 hr periods in certain stretches.
What the essay indicates is a straightforward description of plus and minus effects leveling the balance of nature. Yes, ozone layer has an effect on chemical structure breakdown but the hoo-ha has largely gone away and cries of calamity are less virile.
O.K. accurate measurement and other detailed features (plankton effect, algal blooms, deforestation) would be difficult to measure with any accuracy or counter result but the essay is good, basic stuff and should be enough to introduce into the education system.
Most commentaries within WUWT info have good, grounded scientific basis and yet attempts to shoot the messenger still prevail. Let’s build on the knowledge to see how the strength of the original “argument” can be supported. That way, any supposed failings can be gathered and maintained as a separate review for open discussion. They may also highlight:- the Calvin Cycle, the Nitrogen Cycle, the Evaporative Cycle and enable comparison in a review of each (and/or multiple) effects within various Holocene approaches or tails.
Positioning of Planetary Gravitational bodies, the Sun relationship within such gravitational mass position, the various orbit effects for the Earth in relation to warming and cooling periods and so on.
Come on folks! The 310 million users within this site should be able to overcome Political Prophets of Doom.
Makes you wonder how fast atmospheric carbon dioxide would drop without humans.
ChuckWright,
The observed sink rate of any CO2 above steady state (dynamic equilibrium) between atmosphere and oceans (~290 ppmv for the current average ocean surface temperature) is ~51 years or a half life time of ~35 years.
Thus the current 400 ppmv would drop to 345 ppmv in 35 years, 312 ppmv in 70 years,… until ~290 ppmv is reached about the same as in previous interglacials.
Better keep it high for plant life…
I doubt it..
Pismo Donzi,
The net sink rate is what is measured in the past 60 years, surprisingly linear in ratio to the extra CO2 pressure in the atmosphere above the equilibrium (“steady state”) between atmosphere and ocean surface for the current average ocean surface temperature per Henry’s law…
Henry’s Law has rarely applied to natural waters of different salinities and currants moving from cold poles through warm equatorial water’s. Because they’re not under lab conditions. Pour a cold soda water and in time it as it warms loses its carbonation, raise the temperature and it will all be gone. Add electrolytes and the bond is harder to break. Oceans are not homogenized bodies of water. Making Henry’s Law is a farce when used on them.
People from both sides of the aisle often seem quite happy to describe certain regional and temporal carbon sinks and sources as being influenced by the thermodynamics of photosynthesis and other biochemistry, yet seem equally happy to ignore the effect of carbonic anhydrase on the rate constant where it presents in the chemical monolayer covering most of the water surface of the planet. Perhaps if biochemistry only increased the rate constant by a factor of two over the uncatalysed rate constant then it might get some attention because the actual ratio being closer to tens of millions is simply too big to sink in.
Carbonic anhydrase activity also catalyses the ‘inorganic’ exchange driven by temperature changes. A significant question is: “Do many observations that often appear to follow Henry’s law do so because of carbonic anhydrase activity, or in spite of carbonic anhydrase activity?
“The observed sink rate…”
This is a static interpretation of a dynamic system. It does not tell us what nature is doing on its own, only what is happening with the addition of anthropogenic input, which itself induces sink activity. A static analysis is not sufficient for determining attribution from such an observation.
This is the pseudo-mass balance argument. It appeals to the naive, but it has no bearing on the question of attribution.
Net sink rates 1959-2012:
Assuming a small dependency of CO2 at ~16 ppmv/K temperature change of the sea surface temperature:
In 1959: ΔpCO2(atm-ocean): 25 ppmv; net sink rate: 0.5 ppmv/year; e-fold decay rate ~50 years.
In1988: ΔpCO2: 60 ppmv; net sink rate: 1.13 ppmv/year; decay rate 53 years.
In 2012: ΔpCO2:110 ppmv; net sink rate: 2.15 ppmv/year; decay rate 51.2 years.
In reverse calculation: take the 1988-1959 difference or the 2012-1959 difference in net sink rate and calculate the equilibrium where the net sink rate is zero. Both give 280-290 ppmv.
Looks very linear to me, widely within the borders of accuracy of the emission inventories and natural sink capacity variability, while that includes the full dynamics of the (deep) ocean-atmosphere interchanges.
“Looks very linear to me…”
Also irrelevant.
Well, if it looks like a duck and walks like a duck and quakes like a [duck], it probably is a duck.
If a CO2 removal process reacts quite linear to an increase in the atmosphere and two separate backcalculations show the same common steady state, which not by coincidence is the same as what Henry’s law predicts, confirmed by the ice cores CO2/T ratio over the past 800,000 years, then there is a high probability that it is a linear process, no matter the dynamics of the ocean-atmosphere system…
True. More colorfully put:
Michael Hart,
The full chemical train between free CO2, H2CO3, HCO3- and CO3– is quite fast in seawater: the exchanges in the ocean surface follow changes in the atmosphere (or reverse) with a tau of less than a year. That is not the limiting factor. The limiting factor is the drop in pH due to more CO2 in seawater for an increase in the atmosphere. That pushes the equilibria back to free CO2. The net result is that per Henry’s law, a 100% increase of CO2 in the atmosphere gives a 100% increase of free CO2 in the ocean surface, for seawater and fresh water alike, but only a 10% increase in total inorganic carbon (DIC) in the sea surface (that is the Revelle factor).
The reason: in fresh water free CO2 is ~99% of all carbon species, in seawater it is only 1%, 90% is bicarbonate and 9% is carbonate. If free CO2 doubles, it gets 2% of DIC, at the cost of mainly carbonate…
See the Bjerrum plot at:
https://en.wikipedia.org/wiki/Bjerrum_plot
Despite the saturation of the ocean surface (NOT the deep oceans) due to buffer chemistry, seawater does absorb about 10 times more CO2 than fresh water for the same CO2 pressure increase in the atmosphere.
The author says: “All oil, natural gas and coal are derived from buried organic matter which has been compressed and heated over millions of years.”
How do we explain methane on Titan if organic matter is required?
Why reinvent the wheel? IPCC AR5 already covered the carbon cycle in figure and table 6.1. Atmospheric carbon (CO2) went from about 1.3 to 1.8 percent between 1750 and 2011. The uncertainty in the cycle numbers are on the order of +/- 3%.
Nothing but a great big WAG. Nobody can say with certainty or precision where the atmospheric CO2 comes from, where it goes and which of multiple sources is responsible.
Integrating measured isotope ratios into the supposed fluxes provides interesting constraints on the Carbon cycle. All of the interactions with the atmosphere except vegetation result in a reduction of atmospheric per mil 13C. The isotopic composition of atmospheric Carbon (-8 PDB) is well known and has decreased from -6.5 PDB at the industrial revolution, a rate of about -.01 per year. More recently the rate of decrease has been measured at -.016. This matches the human input well, but unfortunately, this rate of decrease cannot be replicated without a large input of 13C; about 300 “gigaton per mils”.
http://geosciencebigpicture.com/2017/05/21/the-missing-13c/
Isotopes are just a giant handwavium SWAG. Better than tea leaves, but not by much.
Isotopes ratios are measures of masses, primarily protons and neutrons, in molecules and their constituent atoms. They are measured very accurately these days. You begin to sound like a flat earther if you deny the technology.
Undeniably, the Carbon cycle is a WAG. Undeniably, errors are made in sampling locations and procedures for isotope measurements. Nothing is certain.
We can throw up our hands and bow to Mecca, or press ahead with the best information we have.
We need all the understanding we can muster to constrain the Carbon cycle. If it were a small deviation, the missing 13C would be a joke. The missing 13C is a larger factor than human input.
Last year NASA published a study that indicated that the planet had greened by almost 14% between 1980 and 2010 as measured by satellites. The study estimated that over 70% of this greening was due to increased CO2. Presumably photosynthesis absorption would have increased also by 14% over the same (approx 55Gt) offset to some extent by more emissions from plant respiration and decay. One wonders if there is a self regulating mechanism at play here. More CO2 , more plants, more absorption of CO2.
Tom,
Well, dooh!
Chimp
May 21, 2017 at 4:43 pm
says
Before cyanobacteria, Earth’s oceans were blood red, due to all the iron dissolved in them. Once oxygen became available, this iron rusted and settled to the bottom forming the red-banded ore deposits
In a reducing atmosphere iron is in the form of Fe ++ ions. Fe++ is pale green not red.
Iron as an element rarely occurs on Earth.
Iron Fe does not rust in the ocean. Green Fe++ is oxidized to red Fe+++
https://www.researchgate.net/publication/252111554_The_evolution_of_ocean_color
You’re right that seawater itself would have been greenish, except for the life in it. Oceans looked red in the Archaean Eon, thanks to anaerobic microbes similar to those which cause red tides today under anoxic conditions.
http://www.nature.com/ngeo/journal/v8/n2/full/ngeo2327.html
From a 2006 study cited in the above 2015 link:
“Fe(II) can function as an electron source for iron-oxidizing microorganisms under both oxic and anoxic conditions and Fe(III) can function as a terminal electron acceptor under anoxic conditions for iron-reducing microorganisms.”
If it were not for the human factor, CO2 in the atmosphere would decline until a severe crisis occurred in the biosphere. That crisis would become an extinction. From the mass of detritus, fungi would run riot, releasing CO2 to reset the system. Alas, it is unlikely most of the present species would survive the event.
For a comprehensive discussion of the terrestrial/marine carbon cycle, including reactive, conservative, and non-reactive dissolved species, pH stabilization in ocean waters, ocean acidification (it’s NOT CO2-related!), and operations of the critical Fundamental Equations of Life and Death, see my new book: “In Praise of Carbon: How We’ve Been Misled Into Believing that Carbon Dioxide Causes Climate Change” by David Bennett Laing on amazon.com.
https://www.amazon.com/dp/B01N7ZXTID
“In fact, all life on this planet is based on hydrocarbon compounds which include carbon, hydrogen and oxygen.”
Shouldn’t “hydrocarbon” in the above sentence read instead “carbohydrate”?
Hydrocarbons are compounds of hydrogen and carbon, while carbohydrates also contain oxygen. Consider the simple hydrocarbon methane (CH4) v. the simple carbohydrate glucose (C6H12O6), the sugar which photosynthesizers make from the precious CO2 in our air by combining it with H2O, while releasing the O2 we all need to live.
Maybe a nitpick, but who wants nits?
Excellent post. Much food for thought here.