A response to
The Ice Age Cometh! Forget Global Warming! actually another thread, but this comment became much more than a talk about ice age, as it deals with some of the arguments about CO2 and its behaviour in the geophysical system:
For those who might have missed it on Sott, astrophysicist Piers Corbyn (brother of Jeremy) lays it all out:
[...]
From the transcript fo the Youtube
02:28 all 02:30 all sides will agree this that there is 02:32 50 times more carbon dioxide in the sea 02:36 than there is in the air 02:39 okay now that means and there's going to 02:43 be a level between them and the level 02:45 the balance level between the two of 02:47 them is the saturation level of co2 in 02:51 the air will depend on the temperature 02:53 of the sea you warm up the sea a bit 02:55 like warm up a glass of water some gases 02:57 will come off nitrogen oxygen carbon 02:59 dioxide will come off you cool down a 03:01 glass of water and it can absorb more of 03:04 those gases that's very straightforward 03:06 very simple and very basic physics 03:08 because there's 50 times more co2 in the 03:12 sea than in the air it means basically 03:14 whatever man does to the air will have 03:17 no effect because the co2 will 03:18 compensate if man puts extra co2 into 03:22 the air or nature or termites or anybody 03:25 put co2 into the air it will just go 03:27 into the sea depending on the Seas 03:29 temperature and if you take it out of 03:32 the air then it will come out of the sea 03:34 and the levels will stay the same 03:36 according to what's called Henry's law 03:39 issue the equilibrium levels of a liquid 03:43 and a gas at a certain temperature so 03:46 the co2 theory is wrong from the start 03:51 even if you believe a co2 is having an
03:54 impact the co2 levels can't change under 03:57 man's influence is a fact is the Sun 04:00 rules the sea temperature and the sea 04:03 temperature rules the climate
Piers Corbyn explains why reducing CO2 is not going to help by referring to Henry's Law. In this post there will be much more about Henry's Law, much more. I thought it would be a simple question, but it wasn't because in the process of understanding the small problem others kept coming. Before getting lost in the details, that may be relevant in some situations, Corbyn's argues that pumping CO2 out of the atmosphere will not help, because there is much more in the sea that then will be released. I think he is right, but others might say that CO2 appears faster in the atmosphere than it can be absorbed in the short term, and if they then believe that CO2 is all the fault of humans and the whole AGW ideology, then they think they have to do something.
Explanation of Henry's Law
If you like video there is a general explanation on Khan Academy, but it takes a few minutes:
Henry's law and an example showing the difference in solubility between oxygen and carbon dioxide:
Get an intuition for why carbon dioxide is so much more soluble than oxygen when it goes into water. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to...
www.khanacademy.org
There is also this explanation
Henry's law - Wikipedia in text:
In physical chemistry, Henry's law is a gas law that states that the amount of dissolved gas in a liquid is proportional to its partial pressure above the liquid. The proportionality factor is called Henry's law constant. It was formulated by the English chemist
William Henry, who studied the topic in the early 19th century. In his publication about the number of gases absorbed by water,
[1] he described the results of his experiments:
..."water takes up, of gas condensed by one, two, or more additional atmospheres, a quantity which, ordinarily compressed, would be equal to twice, thrice, &c. the volume absorbed under the common pressure of the atmosphere."
An example where Henry's law is at play is in the depth-dependent dissolution of oxygen and nitrogen in the blood of
underwater divers that changes during
decompression, leading to
decompression sickness. An everyday example is given by one's experience with
carbonated soft drinks, which contain dissolved carbon dioxide. Before opening, the gas above the drink in its container is almost pure
carbon dioxide, at a pressure higher than
atmospheric pressure. After the bottle is opened, this gas escapes, moving the partial pressure of carbon dioxide above the liquid to be much lower, resulting in degassing as the dissolved carbon dioxide comes out of solution.
I am going to come back to Henry's Law but just one observation, because it seems not all scientists would use it as part of an explanation or maybe the journalist mixed it up:
A companion phenomenon of emitting CO2 into the atmosphere is the loading of the oceans with elevated levels of carbon dioxide created by fossil fuel burning and other human activities. Recent estimates have calculated that 26 percent of all the carbon released as CO2 from fossil fuel burning, ce
scripps.ucsd.edu
But will the oceans always be able to take up that proportion of human CO2 emissions year in and year out?
Probably not in the near term, said Scripps Institution of Oceanography, UC San Diego marine chemist Andrew Dickson.
[...]
Dickson noted that although the oceans presently take up about one-fourth of the excess CO2 human activities put into the air, that fraction was significantly larger at the beginning of the Industrial Revolution. That’s for a number of reasons, starting with the simple one that as one dissolves CO2 into a given volume of seawater, there is a growing resistance to adding still more CO2.
I have some difficulty understanding how the above makes sense according to Henry's law, if there is an equilibrium between the amount in the gas and the amount in the water, a higher concentration of CO2 in the atmosphere should alow for more CO2 to be absorbed by the water, but is he suggesting it is not as proportionate as one should expect? There is a slide show
https://www.iaea.org/sites/default/files/18/07/oa-chemistry-dickson-050916.pdf with some more ocean chemistry. From the above there was a recommendation to consult the
Guide to Best Practices for Ocean CO2 Measurements There they introduce a concept, fugacity, that revolve around the reality that CO2 does not behave completely like an ideal gas. The explanation in one chapter is followed by another filled with chemistry and mathematics. If one takes a look at one illustration from page 3 of chapter 2 there is:
View attachment 32462
The interpretation, I have is that the deviation of CO2 from being an ideal gas is more pronounced when it is at lower temperatures, when it is a pure CO2 gas, and less when it is mixed up with air. One possible explanation for this variation could be that CO2 is a more heavy molecule than both nitrogen (CO2 is three times heavier) and oxygen (1/3 heavier). At the same time, reading the numbers in the diagramme, this deviation from behaving as expected for an ideal gas is small, like less than one percent. This is important when one needs to get everything right, but I can still not find a clear explanation for the statement they have that the ocean absorbs relatively less now than at the beginning of the industrial revolution. To me a better explanation might be inertia, as there is only so much water surface compared to the kilometers of atmosphere above the ocean. Building high chimneys might reduce the time it takes to get close to water. Also there are more factories away from the sea and in hot climates and not cold Britain, where CO2 is less readily absorbed by the water. Maybe one could counter such arguments by claiming that the proximity to water is not so important if much of the CO2 that gets absorbed by the ocean actually does so indirectly by receiving rain that has absorbed CO2 in the atmosphere. However I don't know which plays a greater role. In the following I will work with Henry's law assuming that CO2 is pretty close to behaving as a natural gas.
Henry's Law and some calculations
The reason a gas exerts pressure is because the gas molecules move. The more they move, or the more that are confined to a unit of space the higher the pressure. If we from outside wish to change the speed of the many tiny gas molecules, we can change the temperature. If it is warmer, the molecules mover faster and the pressure increases, if it is colder they move slower, and the pressure of the gas decreases. This relationship is expressed in the ideal gas law:
en.wikipedia.org
The
ideal gas law, also called the
general gas equation, is the
equation of state of a hypothetical
ideal gas. It is a good approximation of the behavior of many
gases under many conditions, although it has several limitations. It was first stated by
Émile Clapeyron in 1834 as a combination of the empirical
Boyle's law,
Charles's law,
Avogadro's law, and
Gay-Lussac's law.
[1] The ideal gas law is often written as
{\displaystyle PV=nRT,}
where {\displaystyle P}
, {\displaystyle V}
and {\displaystyle T}
are the
pressure,
volume and
temperature; {\displaystyle n}
is the
number of moles of gas; and {\displaystyle R}
is the
ideal gas constant. It is the same for all gases.
Ideal gas law - Wikipedia
Ideal gas law - Wikipedia
One mole of gas is the mass of 6.022 x 10^23 molecules. If we take air, it consists of various gases including nitrogen, oxygen, argon and others which make up about 0.4 % including water vapor and carbon dioxide. Each gas contributes to the pressure we experience in an approximate proportion to how much volume they take op.
There are tables that show how much water is needed to dissolve one mole of the various gases. In order for one mole of nitrogen to be dissolved in water at 25 degrees or 298 Kelvin at one atmosphere of pressure, one needs 1639 liters of water, for one mole of oxygen one needs 769 liters, but for CO2, carbon dioxide, one only needs 29.4 liters of water. One liter water is also 55,55 moles of H2O since one mole of water is 18 grams (The two moles of hydrogen atoms weigh 1 gram each and one mole of oxygen 16 grams, we combine them and get 1 mole of H2O, weighing 18 grams. 18 grams per mole times 55,55 moles per liter gives us 1000 grams per liter). Therefore in some tables they will tell you that in order to dissolve one mole of CO2 at one atmosphere you will need around 1630 moles of water [1630 atm · mol soln / molgas]. (This is approximately 55.55 moles of per liter of water times 29.4 atm liter of water/moles of CO2) The different methods of listing the Henry constants are explained both in the Wiki and in this document:
Use Henry's Law to Calculate Concentration of Gas in a Solution
The amount that can be dissolved varies very much with the temperature, as I alluded to previously when I mentioned factories in hot climates versus cold climates. At a lower temperature more CO2 can be dissolved in water. From the diagram below, it appears that cold water at 0 degrees can hold twice as much CO2 as warm water at 25 degrees when the pressure from CO2 in the gas above the water is the same.
https://demonstrations.wolfram.com/TemperatureDependenceOfHenrysLawConstant/
View attachment 32459
The units along the y-axis are different and not described, but the idea is, as mentioned, that at one atmosphere of pressure one needs 1630 moles of water to dissolve on mole of CO2.
If we compare the solubility of oxygen with that of carbon dioxide at 25 degrees, then we have 769 liters/ ("/" is divided by) 29.4 liters which gives us that carbon dioxide is 26 times more soluble in water than oxygen, at least when the temperature is 25 degrees.
In the air, there are by volume 20.95 % of oxygen according to
Air - Molecular Weight and Composition while CO2 is around 410 ppm (parts per million) according to
Climate Change: Atmospheric Carbon Dioxide | NOAA Climate.gov 410 ppm is 410/1000,000 or 0.041 %. If one compares the volume percentage of oxygen with that of CO2, that is 20.95 % / 0.041 % then we have that the volume amount of oxygen, O2 is about 510 times larger than the volume amount of carbon dioxide, CO2.
If we compare the results in two previous paragraphs, then on the one hand we found that CO2 is 26 times more soluble in water than oxygen. We also found that oxygen, in the air we breathe by volume takes up 510 more space than CO2. If this is true then we should find 510/26 or about 20 times more oxygen than CO2 dissolved in the water.
The ICCP in their report have thought about storing CO2 in the deep ocean.
https://www.ipcc.ch/site/assets/uploads/2018/03/srccs_chapter6-1.pdf there is this illustration:
View attachment 32467
Since the pressure increases rapidly with depth, (one atmosphere for every 10,33 meters), then the ocean could contain more CO2, just like a bottle of sparling water contains more than the usual water.
See also
Ocean storage of carbon dioxide - Wikipedia
These people wish to vilify CO2, so essential for life, rather than allowing it to find a place where it wants, and have a chance to get a life, quite literally, as say carbon in a plant, oxygen for breathing or? Most of what they wish to bury is not carbon, it is oxygen. If one mole of CO2 is 44 grams, the 32 are from oxygen, only 12 from carbon. Isn't this all sadly symbolic?
For something more uplifting consider this shell model of carbon dioxide from
Shell Model of Carbon Dioxide
And why not present the story, from the same page, behind the model which tells us something about cooperation at a very fundamental level, an expression of deeper principles.
The carbon atom (in the middle) has four electrons in its outer shell.
The two oxygen atoms each has six electrons in their outer shells.
To complete their shells (which all atoms want to do), every one of these atoms needs to have 8 electrons in its outer shell.
So the central carbon needs to gain 4 electrons, and each oxygen atom needs to gain 2.
Because of the cloud-like nature of the electron, it can be in several places at once. An electron can move round two atoms at the same time. If an atom shares one of its electrons with another atom, BOTH atoms gain an electron, so filling a hole in their outer shells. So atoms join together to share pairs of electrons.
The carbon shares two of its electrons with each oxygen, so each oxygen gains two electrons and hence gains a full outer shell. Each oxygen shares two of its electrons with the carbon, so the carbon gains four electrons, and so gets a full outer shell too.
Each pair of electrons is called a covalent bond. So the carbon atom has 4 covalent bonds, two with each oxygen atom. We call these DOUBLE BONDs.
Isn't it beautiful?