Sunday, 6 May 2018

Ocean acidification myth

pH is a measure of acidity (or basicity). When pH is below 7 solutions (like the oceans) are said to be acidic. With pH above 7 they are basic. Ocean pH is about 8, basic. It actually varies quite a lot depending on which ocean you measure, at what depth.

Climate alarmists claim CO2 from fossil fuel combustion is acidifying oceans, because it makes "carbonic acid".

NOAA claim:

"In the past 200 years alone, ocean water has become 30 percent more acidic"
due to CO2 from burning fossil fuel.

National Geographic claim:

"Over the past 300 million years, ocean pH has been slightly basic, averaging about 8.2. Today, it is around 8.1, a drop of 0.1 pH units, representing a 25-percent increase in acidity over the past two centuries."

Let me examine NOAA's claim:

1) There is 38,000 Gt on carbon dissolved in oceans (27ppm). Mostly as the bicarbonate ion HCO3- Total carbon available in fossil fuel reserves = 5,000 Gt. If all that fossil fuel burnt, and the CO2 produced then dissolved in the oceans it will raise the ocean carbon content to 31ppm. To put things into perspective: in contrast to the 27ppm of carbon, oceans have 35,000ppm of salt in them.

Total carbon emissions (as CO2) since before industrial times ~ 500 Gt. Not all that can end up in oceans. Some stays in atmosphere, some is sequestered on land (in plants and trees), more is sequestered by oceans.

2) When carbon dioxide dissolves in water. It first becomes CO2(aq). Then:

CO2(aq) + H2O(aq) ⇌ H2CO3(aq) ... (A)

H2CO3(aq) is "carbonic acid".

But when this happens only 0.3% of the CO2 dissolving in the oceans becomes "carbonic acid". The rest mostly stays as CO2(aq).

Note: For the 0.3% claim see: "Carbon Dioxide, Dissolved (Ocean)" by Zeebe & Wolf

3) When this "carbonic acid" is made it is a very weak acid. With a Ka = 4.2E-04 (Ka = dissociation constant). This is the dissociation of H2CO3(aq) to make acid:

H2CO3(aq) + H2O ⇌ H3O+(aq) + HCO3-(aq) ... (B)

The actual (active) acid here is H3O+(aq), sometimes written as H+(aq), and referred to as "hydrogen ions", or hydrated hydrogen ions. This is what pH measures. pH is literally "the negative log of the hydrogen ion concentration".

Such a low dissociation constant implies about 0.5% of the carbonic acid (H2CO3) will act as acid (as hydrogen ions). [calculated as the square root of Ka a by a "very back of envelope" method!].

So 0.5% of 0.3% of 500Gt is how much actual acid could have been made. Insignificant.

Note: In comparison a strong acid like hydrochloric acid is almost 100% dissociated to make actual "acid", or hydrogen ions, which may be written H+(aq) or H3O+(aq).

4) Carbon dioxide dissolving in oceans acts as a buffer, not an acid. As the name implies, a buffer prevents, or greatly reduces, pH changes.

5) What kind of pH change might we really expect?

I will do "very back of the envelope" calculations here. If I make a mistake, please laugh at me. Then correct me.

Assuming the pH of oceans = 8.1, as National Geographic claim, lets do the back of envelope calculations to figure out how much pH may have fallen in the last 200 years.

The mass of oceans is usually given = 1.4E24 grams. How much acid is that?

A pH = 8.1 says that the [H3O++] = 10-8.1 = 7.9433E-09.

Multiply the two. Grams of H+ = 1E16 grams (very approximate!). A lot of hydrogen ions, but then, our oceans are very big.

How many hydrogen ions may we expect from 500Gt of carbon (dissolving as CO2)? The Atomic Mass of C = 12. 500Gt of carbon = 500 × 1000,000,000 t = 500 × 1000,000,000,000,000 g = 50E16 g of Carbon = 50/12 × 1016 moles, or 4E+16.

4E+16 × 0.3% × 0.5% = 6E+11 hydrogen ions. The ratio of hydrogen ions added is 18600:1 We increased the acidity from 18600 to 18601. Big deal! By adding all that CO2 we made the oceans more acidic by 1 extra hydrogen ion in 18600. An addition of 0.0054%, not 30% as NOAA said. The pH change we may expect to actually get is too small to measure. It will be within the error bounds of any measurement we make. We won't be able to distinguish it from signal noise.

The claimed pH change from 8.2 to 8.1 as NOAA and National Geographic claim is a 26% change in acidity (remember pH is a logarithmic scale). The actual change must be less than 0.0054%. They exaggerate by over 3 orders of magnitude. By 26% ÷ 0.0054% = 4819. National Geographic by 4819 times. NOAA by 5560 times.

6) Evidence suggests fraud in the "science" as well.

The pH data has been tampered in the CO2-AGW consensus paper on declaring ocean water acid by 0.1 decrease. The reanalysis of public pH data from the same source in Univ of Hawaii shows the data tampering in the peer-reviewed consensus paper.

Note: The pH standard deviation range = 0.19 - 0.28.

Note: Ocean acidification of the North Pacific Ocean (pdf), by Richard A. Feely, Victoria J. Fabry and John M. Guinotte

7) A reply from a critic

There is at least one attempt to refute me here: Bad Science or "Climate Alarmism". You tell me

Summary:

  1. The relative change in the carbon content of oceans in the last 200 years is small.
  2. Only 0.3% of carbon dioxide dissolving in oceans becomes carbonic acid.
  3. This carbonic acid is a weak acid, with 0.5% of it dissociating to actual acid (hydrogen ions).
  4. CO2 in sea water acts as a buffer. To prevent changes in pH (acidity)
  5. NOAA exaggerate the change in likely pH 5560 times over.
  6. Reanalysis of the scientific paper claiming oceans have become more acidic by 0.1 pH shows the paper cannot be trusted.

This is the best reply I've had so far.


chiralSPO, Global Moderator, Naked Science Forum King!

Ocean pH is due to only one thing [H+]. Yes, there are many other ions in solution, each of which might play a role in determining [H+], though not as many as you seem to be indicating (it doesn't matter how much salt there is: Na+, K+, Cl, and Br will have NO effect on pH in the range of plausible pH values, as the pKa values of Cl, and Br are < 0).

There is a complex "buffer" related to concentrations of CO2, HCO3, CO32–, H2PO4, HPO42–, B(OH)3, B(OH)42–, Mg2+, Ca2+, etc.

As you say in your blog:
Quote
I will do "very back of the envelope" calculations here. If I make a mistake, please laugh at me. Then correct me.
I will skip the first step, and focus on the second:

Quote
Assuming the pH of oceans = 8.1, as National Geographic claim, lets do the back of envelope calculations to figure out how much pH may have fallen in the last 200 years.

The mass of oceans is usually given = 1.4E24 grams. How much acid is that?

A pH = 8.1 says that the [H3O++] = 10-8.1 = 7.9433E-09.

Multiply the two. Grams of H+ = 1E16 grams (very approximate!). A lot of hydrogen ions, but then, our oceans are very big.

How many hydrogen ions may we expect from 500Gt of carbon (dissolving as CO2)? The Atomic Mass of C = 12. 500Gt of carbon = 500 × 1000,000,000 t = 500 × 1000,000,000,000,000 g = 50E16 g of Carbon = 50/12 × 1016 moles, or 4E+16.

4E+16 × 0.3% × 0.5% = 6E+11 hydrogen ions. The ratio of hydrogen ions added is 18600:1 We increased the acidity from 18600 to 18601. Big deal! By adding all that CO2 we made the oceans more acidic by 1 extra hydrogen ion in 18600. An addition of 0.0054%, not 30% as NOAA said.

The above approach is fundamentally flawed (I have stricken the primary mistake through). As you point out, the system is buffered, by the equilibrium of H+ CO2, H2CO3, HCO3, and CO32–. This complex buffering means that the linear relationship assumed in the above calculation is not valid. Instead, we need to consider the relationship between all of the species. You have also not considered how much of each of the carbon-related species are already in solution, and what their relationships are to each other and to pH.

I recommend studying up on this more before posting:

https://en.wikipedia.org/wiki/Bicarbonate_buffer_system#Henderson%E2%80%93Hasselbalch_equation
http://www.atmos.umd.edu/~russ/620_04OceanChem.pptx (downloadable lecture slides)

It is also worth emphasizing (and you have noted it, but I think you should consider the ramifications more carefully), that the system is NOT IN EQUILIBRIUM. The pH is not the same everywhere because the ocean is not mixed perfectly well. This means that at the very surface, where the ocean is in contact with the acidifying CO2, the buffer can be temporarily over-burdened, before more bicarbonate comes up from the depths to restore equilibrium. This is bad news for marine life in shallow waters (read: everything you can see while snorkeling), which is damaged by the imbalance, even if it is temporary.

Essentially, the calcium carbonate in the marine organisms serves as the base in the equilibrium.

Saturday, 14 April 2018

Nazis and Environmentalism

James Delingpole interviews Rupert Darwall, author of "Green Tyranny"

In addition

The Nazi's were very concerned about German food sustainability. A big factor in Germany's WWI loss, was the Allied blockade leading to starvation in Germany. By the end of 1918, 763,000 German civilians died from starvation and disease. This was followed by 15 years of economic devastation and poverty for many.

Nazi's believed that the US standard of living, which they envied, was directly proportional to its agricultural production. Hitler wanted a better living standard for Germans. They also believed that German agricultural productivity was maxed out by the 1930s. That German agriculture could make no big gains in productivity.

Hence, before WWII, Germany secretly proposed to Poland, no less than eight times, a join German-Polish invasion of the Soviet Union because the Nazis wanted to annex the Ukraine for Germany. German farmers would then colonize the Ukraine; one of the most fertile agricultural regions, close to Germany.

This belief in the absoluteness of limits to the economy, we can call it neo-Malthusianism, is central to Green thinking.

Leading Nazis were vegetarians too. Not because they loved animals, but because they considered it morally repugnant to eat meat. Because arable land can support 15 times the population that pastoral land does. Eating meat, while other Germans starved was morally repugnant to them.

Revealed in Black Earth, by Timothy Snyder.

Tuesday, 20 March 2018

The elementary error of physics that caused the global warming scare

Global warming on trial and the elementary error of physics that caused the global warming scare
Above all, the current method of deriving Charney sensitivity is based upon the elementary and significant physical error of assuming that the Earth’s large emission temperature induces no feedback response whatsoever, while the next few Kelvin of temperature forced by the presence of the naturally-occurring greenhouse gases is imagined to induce a large feedback. That contradiction is untenable. For half a century, climate science has simply been wrong.

Saturday, 17 March 2018

Naturalism is the root cause of green fallacies.

Environmentalists assume that environmental change caused by humanity is bad, but that much larger 'natural' changes are neutral. This is because they often suffer a 'naturalist fallacy' or "appeal to nature". Because natural is defined as good in their eyes, they can't imagine a bad natural change. In contrast, every man-made change is assumed to be bad, even when the man-made change improves the environment.

This leads to anti-human, anti-environment policies. e.g. Calls for bans against: fishing, genetic engineering, plastic bags, nuclear power, fossil fuels, factory farming, 'chemicals', including pesticides, herbicides, and fertilizers. Greens propose: organic farming, natural energy such as renewable energy systems: wind-, solar-, hydro-, geo-, bio- energies. Every green solution is worse for the environment than the technologies it is designed to replace. Because greens long ago abandoned cost benefit analysis for the 'precautionary principle' they can't even know whether their proposals make sense. Perhaps this may explain why their policies are senseless and they attract so many incompetents to their ranks?

The green sense of moral superiority (rarely made explicit) is often glanced through their outrage against perfectly good technologies which benefit the environment, such as fossil fuel burning. Giving up on cost-benefit analysis means the give up on basic evidence too. This moral superiority is misplaced, and is really outrage against humanity for living so well and improving our lot.

Sunday, 5 November 2017

Greenhouse gas effect: "The Science" vs. science.

Following on from Prof. William Happer's remarks on how the green-house gas effect really works.

The greenhouse effect is often explained in terms of carbon dioxide absorbing long-wave infrared (LWIR) rays leaving earth's surface as the surface cools. Then re-emitting the radiation at the same wavelength. It cannot happen in this manner, so why do 'scientists' describe it this way? Scientists claim they don't believe fairy stories. But some clearly do. A CO2 molecule, in air, typically experiences about 1 billion collisions with other air molecules each second. One second is about the time it would take to re-emit the LWIR it absorbed. In reality, when LWIR is absorbed, it is typically thermalized. Meaning: the energy in the LWIR is shared with other air molecules. This will raise the general temperature of air. But will remove energy from CO2 so that the radiation can't be emitted at the same frequency it was absorbed at.

The absorption length for the existing concentration of CO2 is around 25 meters i.e. the distance to reduce the LWIR intensity by 1/e.

What actually happens is that those radiation frequencies at which CO2 absorbs well are removed from LWIR leaving earth. Yet a proportion of the LWIR, originating from earth's surface is unaffected by any greenhouse gas (GHG). Ignoring scattering it goes straight out to space and earth does, indeed, cool.

So only a proportion of LWIR leaving earth is subject to the greenhouse gas effect (GHGE). Even that energy is not 'trapped'. It is all eventually lost to space. Most of the LWIR subject to GHGE is absorbed by water vapour, not CO2. Much of the LWIR is ignored by GHG. This implies we need more sophisticated GHGE models, which treat different radiation bands according to how GHG affects them. There are clearly some unanswered questions here.

  1. In terms of energy, what proportion of LWIR is entirely unaffected by the GHGE?
  2. Why do climate scientists insist on treating all LWIR in the same way. With the same macro equations which ignore the actual frequencies absorbed and ignored by GHG?
  3. After air is warmed due to thermalization, at what frequencies does the air emit radiation to cool down?
  4. When cooling down, which air molecules emit (O2, N2, H2O, CO2, ... ?), and at what frequencies?
  5. What would a true GHGE model look like?
  6. Can we model the effect of clouds and GHG together to write a proper model?

Those are just some of the questions on my mind.


Saturday, 9 September 2017

The greenhouse gas effect.

Reblog: http://sealevel.info/Happer_UNC_2014-09-08/Another_question.html

Ref: http://www.sealevel.info/Happer_UNC_2014-09-08/


Subject: Another dumb question from Dave

From: David Burton Wed, Nov 12, 2014 at 10:48 PM
To: William Happer
Dear Prof. Happer,

At your UNC lecture you told us many things which I had not known, but two of them were these:

1. At low altitudes, the mean time between molecular collisions, through which an excited CO2 molecule can transfer its energy to another gas molecule (usually N2) is on the order of 1 nanosecond.

2. The mean decay time for an excited CO2 molecule to emit an IR photon is on the order of 1 second (a billion times as long).

Did I understand that correctly?

You didn't mention it, but I assume H2O molecules have a similar decay time to emit an IR photon. Is that right, too?

So, after a CO2 (or H2O) molecule absorbs a 15 micron IR photon, about 99.9999999% of the time it will give up its energy by collision with another gas molecule, not by re-emission of another photon. Is that true (assuming that I counted the right number of nines)?

In other words, the very widely repeated description of GHG molecules absorbing infrared photons and then re-emitting them in random directions is only correct for about one absorbed photon in a billion. True?

Here's an example from the NSF, with a lovely animated picture, which even illustrates the correct vibrational mode:

(Aside: it doesn't really shock me that the NSF is wrong -- I previously caught them contradicting Archimedes: before & after.)

If that NSF web page & illustration were right, then the amount of IR emitted by CO2 or H2O vapor in the atmosphere would depend heavily on how much IR it received and absorbed. If more IR was emitted from the ground, then more IR would be re-emitted by the CO2 and H2O molecules, back toward the ground. But I think that must be wrong.

If 99.9999999% of the IR absorbed by atmospheric CO2 is converted by molecular collisions into heat, that seems to imply that the amount of ~15 micron IR emitted by atmospheric CO2 depends only on the atmosphere's temperature (and CO2 partial pressure), not on how the air got to that temperature. Whether the ground is very cold and emits little IR, or very warm and emits lots of IR, will not affect the amount of IR emitted by the CO2 in the adjacent atmosphere (except by affecting the temperature of that air). Is that correct?

Thank you for educating a dumb old computer scientist like me!

Warmest regards,
Dave


From: William Happer Thu, Nov 13, 2014 at 11:29 AM
To: David Burton

Dear David,

Some response are entered below in square brackets and upper case.  Thanks for your interest!

Will

From:David Burton
Sent: Wednesday, November 12, 2014 10:49 PM
To: William Happer
Subject: Another dumb question from Dave

Dear Prof. Happer,

At your UNC lecture you told us many things which I had not known, but two of them were these:

1. At low altitudes, the mean time between molecular collisions, through which an excited CO2 molecule can transfer its energy to another gas molecule (usually N2) is on the order of 1 nanosecond.

2. The mean decay time for an excited CO2 molecule to emit an IR photon is on the order of 1 second (a billion times as long).

Did I understand that correctly? [YES, PRECISELY.  I ATTACH A PAPER ON RADIATIVE LIFETIMES OF CO2 FROM THE CO2 LASER COMMUNITY. YOU SHOULD LOOK AT THE BENDING-MODE TRANSITIONS, FOR EXAMPLE, 010 – 000. AS I THINK I MAY HAVE INDICATED ON SLIDE 24, THE RADIATIVE DECAY RATES FOR THE BENDING MODE ALSO DEPEND ON VIBRATION AND ROTATIONAL QUANTUM NUMBERS, AND THEY CAN BE A FEW ORDERS OF MAGNITUDE SLOWER THAN 1 S^{-1} FOR HIGHER EXCITED STATES. THIS IS BECAUSE OF SMALL MATRIX ELEMENTS FOR THE TRANSITION MOMENTS.]
 

You didn't mention it, but I assume H2O molecules have a similar decay time to emit an IR photon. Is that right, too? [YES.  I CAN'T IMMEDIATELY FIND A SIMILAR PAPER TO THE ONE I ATTACHED ABOUT CO2, BUT THESE TRANSITIONS HAVE BEEN CAREFULLY STUDIED IN CONNECTION WITH INTERSTELLAR MASERS. I ATTACH SOME NICE VIEWGRAPHS THAT SUMMARIZE THE ISSUES, A FEW OF WHICH TOUCH ON H2O, ONE OF THE IMPORTANT INTERSTELLAR MOLECULES.  ALAS, THE SLIDES DO NOT INCLUDE A TABLE OF LIFETIMES. BUT YOU SHOULD BE ABLE TO TRACK THEM DOWN FROM REFERENCES ON THE VIEWGRAPHS IF YOU LIKE. ROUGHLY SPEAKING, THE RADIATIVE LIFETIMES OF ELECTRIC DIPOLE MOMENTS SCALE AS THE CUBE OF THE WAVELENTH AND INVERSELY AS THE SQUARE OF THE ELECTRIC DIPOLE MATRIX ELEMENT (FROM BASIC QUANTUM MECHANICS) SO IF AN ATOM HAS A RADIATIVE LIFETIME OF 16 NSEC AT A WAVELENGTH OF 0.6 MIRONS (SODIUM), A CO2 BENDING MODE TRANSITION, WITH A WAVELENGTH OF 15 MICRONS AND ABOUT 1/30 THE MATRIX ELEMENT SHOULD HAVE A LIFETIME OF ORDER 16 (30)^2 (15/.6)^3 NS = 0.2 S.
 

So, after a CO2 (or H2O) molecule absorbs a 15 micron IR photon, about 99.9999999% of the time it will give up its energy by collision with another gas molecule, not by re-emission of another photon. Is that true (assuming that I counted the right number of nines)? [YES, ABSOLUTELY.]


In other words, the very widely repeated description of GHG molecules absorbing infrared photons and then re-emitting them in random directions is only correct for about one absorbed photon in a billion. True? [YES, IT IS THIS EXTREME SLOWNESS OF RADIATIVE DECAY RATES THAT ALLOWS THE CO2 MOLECULES IN THE ATMOSPHERE TO HAVE VERY NEARLY THE SAME VIBRATION-ROTATION TEMPERATURE OF THE LOCAL AIR MOLECULES.]
 

Here's an example from the NSF, with a lovely animated picture, which even illustrates the correct vibrational mode:

 
Am I correct in thinking that illustration is wrong for about 99.9999999% of the photons which CO2 absorbs in the lower troposphere? [YES, THE PICTURE IS A BIT MISLEADING. IF THE CO2 MOLECULE IN AIR ABSORBS A RESONANT PHOTON, IT IS MUCH MORE LIKELY ( ON THE ORDER OF A BILLION TIMES MORE LIKELY) TO HEAT THE SURROUNDING AIR MOLECULES WITH THE ENERGY IT ACQUIRED FROM THE ABSORBED PHOTON, THAN TO RERADIATE A PHOTON AT THE SAME OR SOME DIFFERENT FREQUENCY.  IF THE CO2 MOLECULE COULD RADIATE COMPLETELY WITH NO COLLISIONAL INTERRUPTIONS, THE LENGTH OF THE RADIATIVE PULSE WOULD BE THE DISTANCE LIGHT CAN TRAVEL IN THE RADIATIVE LIFETIME. SO THE PULSE IN THE NSF FIGURE SHOULD BE 300,000 KM LONG, FROM THE EARTH'S SURFACE TO WELL BEYOND A SATELLITE IN GEOSYNCHRONOUS ORBIT. THE RADIATED PULSE SHOULD CONTAIN 667 CM^{-1} *3 X 10^{10} CM S^{-1}*1 S  WAVES OR ABOUT 2 TRILLION WAVES, NOT JUST A FEW AS IN THE FIGURE.  A BIT OF POETIC LICENSE IS OK.  I CERTAINLY PLEAD GUILTY TO USING SOME ON MY VIEWGRAPHS. BUT WE SHOULD NOT MAKE TRILLION-DOLLAR ECONOMIC DECISIONS WITHOUT MORE QUANTITATIVE CONSIDERATION OF THE PHYSICS.]
 

(Aside: it doesn't really shock me that the NSF is wrong -- I previously caught them contradicting Archimedes: before & after.)

If that NSF web page & illustration were right, then the amount of IR emitted by CO2 or H2O vapor in the atmosphere would depend heavily on how much IR it received and absorbed. If more IR was emitted from the ground, then more IR would be re-emitted by the CO2 and H2O molecules, back toward the ground. But I think that must be wrong.[YES, THE AMOUNT OF RADIATION EMITTED BY GREENHOUSE MOLECULES DEPENDS ALMOST ENTIRELY ON THEIR TEMPERATURE. THE PERTRUBATION BY RADIATION COMING FROM THE GROUND OR OUTER SPACE IS NEGLIGIBLE.  CO2 LASER BUILDERS GO OUT OF THEIR WAY WITH CUNNING DISCHARE PHYSICS TO GET THE CO2 MOLECULES OUT OF THERMAL EQUILIBRIUM SO THEY CAN AMPLIFY RADIATION.]
 

If 99.9999999% of the IR absorbed by atmospheric CO2 is converted by molecular collisions into heat, that seems to imply that the amount of ~15 micron IR emitted by atmospheric CO2 depends only on the atmosphere's temperature (and CO2 partial pressure), not on how the air got to that temperature. [YES, I COULD HAVE SAVED A COMMENT BY READING FURTHER.] Whether the ground is very cold and emits little IR, or very warm and emits lots of IR, will not affect the amount of IR emitted by the CO2 in the adjacent atmosphere (except by affecting the temperature of that air). Is that correct? [YES, PRECISELY.  WE HAVE BEEN TALKING ABOUT WHAT CHANDRASEKHAR CALLS AN “ABSORBING ATMOSPHERE” AS OPPOSED TO A “SCATTERING ATMOSPHERE.”  ASTROPHYSICISTS ARE OFTEN MORE INTERESTED IN SCATTERING ATMOSPHERES, LIKE THE INTERIOR OF THE SUN. THE BLUE SKY DURING A CLEAR DAY IS AN EXAMPLE OF SCATTERING ATMOSPHERE.  VERY LITTLE HEATING OR COOLING OF THE AIR OCCURS WITH THIS “RAYLEIGH SCATTERING.”]


Thank you for educating a dumb old computer scientist like me! [YOU ARE HARDLY DUMB.  YOU GET AN A+ FOR THIS RECITATION SESSION ON RADIATIVE TRANSFER. ]


2 attachments
Statz67-lifetimes.pdf  2090K
H2O-masers.pdf  396K

From: David Burton Thu, Nov 13, 2014 at 11:46 AM
To: William Happer
Wow, thank you very much, Prof. Happer!

I feel like I've just gotten a taste of Princeton education, for free.  You are very, very generous with your time, and I am very grateful.

Warmest regards,
Dave
[...snip...]


From: David Burton Thu, Nov 13, 2014 at 12:53 PM
To: T
Dear T,

I think you will find the discussion below very interesting. Prof. Wm. Happer is one of the world's top experts on CO2's emission and absorption of radiation. He's a colleague of America's most illustrious living scientist, Prof. Freeman Dyson. Prof. Happer's reply to me is in [BLUE] below.

Note that the NSF has got it wrong (again)!

Here's an audio recording + powerpoint of Prof. Happer's lecture at UNC, which prompted this discussion:
Sorry, there was no video recording made, but you can view the powerpoint slides while listening to the audio, which is almost as good.

Warmest regards,
Dave
[...snip...]


From: T Thu, Nov 13, 2014 at 1:03 PM
To: David Burton
Dave,

That is interesting, but not sure what the significance is to the discussion.

If greenhouse gases warm the atmosphere due to absorption of photons, and emission is dependent only on temperature, isn't the net effect the same? A warmer atmosphere emits more LW radiation.
[...snip...]


From: David Burton Thu, Nov 13, 2014 at 1:31 PM
To: T
Hi T,

To me it is interesting for three reasons:

1. It means that the amount of LW IR which is emitted by the CO2 & H2O in the atmosphere, and absorbed by the ground, is independent of the amount of IR emitted by the ground (except that warm ground helps warm the air, through both IR emissions & convection, and the temperature of the air controls the amount of IR that it emits).

2. It means the common description of IR being emitted by the ground, absorbed by the CO2 & H2O vapor, and re-emitted (in a random direction) -- i.e., what the NSF describes -- is wrong.

3. It means my own understanding of how the GH effect works was wrong.

I don't like being wrong. It is uncomfortable. But I like learning, and I learned something new!

Warmest regards,
Dave
[...snip...]


From: T Thu, Nov 13, 2014 at 1:46 PM
To: David Burton
Dave,

I'm not sure that functionally there is any difference. If the ground emits more LW, the atmosphere warms and responds by emitting more LW. So they aren't independent.  That is why the air warms during a sunny day, because of increased IR emissions from the ground.
[...snip...]


From: David Burton Thu, Nov 13, 2014 at 1:56 PM
To: T
T,

The way the NSF describes it (and the way I mistakenly thought it worked), the amount of IR which the ground absorbs from the atmosphere depends almost entirely on the amount of IR which the ground emits. It might not be the very same photons, but it might as well be: the photons the ground receives are just a fraction of those which it emits. But that's wrong.

The reality is that the amount of IR the ground absorbs from the atmosphere depends almost entirely on the air temperature & composition, and not at all on the amount of IR which the ground emits.

The two aren't completely independent, because IR emissions from the ground do affect the air temperature, which, in turn, affects the IR emissions from the air, but the linkage is weak, because other factors (like convective heat transfer) affect air temperature more.

Dave
[...snip...]


From: Robert G. Brown Thu, Nov 13, 2014 at 5:29 PM
To: David Burton
On Thu, 13 Nov 2014, David Burton wrote:

Dear Prof. Brown,
I think you might find the discussion below interesting. Prof. Happer's
reply to me is in [BLUE] below.

Yeah, I already know most of that stuff, and I'm pretty sure I have his
powerpoint presentation slides as well. I wasn't aware that there were
levels with lifetimes as long as 1 second -- that's actually pretty long
as atomic/molecular lifetimes go -- but those particular levels are then
going to be very sharp and not terribly responsive to non-resonant IR.
Either way, CO_2 doesn't "scatter" LWIR radiation, it absorbs it
(typically within a few meters, the mean free path at atmospheric
concentrations) and the energy is almost instantly transferred to the
surrounding air.

That doesn't mean that they don't radiate. It just means that their
radiation temperature is in equilibrium in the surrounding air, and it
isn't reradiating of a photon it absorbed, it is radiation initiated by
e.g. a collision with an air molecule.

That's why the greenhouse effect is basically logarithmic at this point.
It is long ago and overwhelmingly saturated. The atmosphere is
basically totally opaque in the CO_2 aborptive bands from sea level up
to maybe 8 or 9 km. Somewhere up there, where the air is much colder,
the molecules get far enough apart that LWIR emitted from the colder air
have a good chance of escaping without being reabsorbed. Increasing
CO_2 basically causes a very small variation of the average height and
-- due to the adiabatic lapse rate, which has little that is directly
due to the GHE itself -- therefore the temperature at which the
atmosphere becomes effectively transparent. The rate at which the
energy in this band emerges from the atmosphere is hence much less than
the rate at which it was originally emitted at the surface in this band.
Given constant average SWV (visible) delivery of radiation into the
system from the Sun, the ground temperature has to warm a tiny bit in
order to compensate for the loss of outgoing power in the CO_2 band.

Here is a curve indicating just how much explanatory power CO_2 has as
far as the temperatures over the last 164 years are concerned. Quite a
lot, actually. Happer might be interested in this curve. I think he
passed on the reference to Wilson and Gea-Banacloche in AJP (2012) which
reviews the CO_2-only no-feedback GHE and ends up concluding that the
no-feedback total climate sensitivity on doubling CO_2 ought to be
around 0.9 to 1.1C. I get an excellent fit to all of HadCRUT4 with TCS
around 1.8C,

If I add an entirely heuristic (but obvious) harmonic correction to the
fit to account for the 67 year whatever is causing the systematic
variation, the fit is even better, but the direct fit to the physically
motivated log only has enormous statistical explanatory power with a
residual standard error of 0.1 on 163 degrees of freedom and only two
fit parameters, one of which does nothing but line up the (arbitrary)
scale of the anomaly with that of the fit. There is, in fact, almost
nothing left to explain but noise and the harmonic term. Hard to see
why we need to bother with the world's most expensive, difficult,
chaotic, nonlinear, horribly underresolved models at all, if they cannot
beat a one parameter physically motivated radiative model that ignores
everything but CO_2.
 
rgb
[...snip...]
 
Robert G. Brown http://www.phy.duke.edu/~rgb/
Duke University Dept. of Physics, Box 90305
Durham, N.C. 27708-0305
Phone: 1-919-660-2567 Fax: 919-660-2525


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From: David Burton Tue, Jan 20, 2015 at 11:52 PM
To: William Happer
Dear Prof. Happer,

I just stumbled across someone else discussing the same topic, and he came to a "similar" conclusion, sort of. Dr. Joshua Halpern, who blogs under the pen name of Eli Rabett, calculated that 1 in 10^5 rather than 1 in 10^9 IR-stimulated CO2 molecules will give up that energy by re-emisison of an IR photon, rather than collision with another air molecule. He gets about the same radiative lifetime as you, but a collisional lifetime of about 10 microseconds rather than one nanosecond.

A difference of four orders of magnitude suggests to me that he goofed, but I don't understand this well enough to understand how. Here's the article:

Warmest regards,
Dave
[...snip...]
 

From: William Happer Wed, Jan 21, 2015 at 10:05 AM
To: David Burton

Dear David,

Thanks for bringing this to my attention. Measurements show a broadening of order B = 0.1 cm^{-1} = 3 GHz for CO2 lines at 1 atmosphere and 300 K. For example, see Fig. 1 of the attached paper. This would imply a "time between collisions" of t = 1/(2*pi*B) = 50 ps = .05 ns.

The "about a nanosecond" I mentioned was an estimate of the lifetime for velocity changing collisions that go in to the spatial diffusion coefficient. Here are typical numbers:

Density of air molecules at ground level = Loschmidt's number = N = 2.69 x 10 {19} cm^{-3}

Kinetic cross section = sig = pi*(10^{-8})^2 =3.14 x 10^{-16} cm^{2}

Mean relative velocity (roughly sound speed in air) = v = 3.43 x 10^{4} cm s^{-1}

Lifetime = 1/(N*v*sig) = 3.45 ns

On a quick read of Joshua's reference he seems to have assumed that only other CO2 molecules in the air cause deexcitation, but not N2 and O2 molecules. It is true that the "self-quenching" rates for CO2-CO2 collisions are much larger, typically a factor of 10 if my memory serves, than the rates for CO2-N2 collisions, but there are thousands of times more N2 and O2 molecules so they dominate the deexcitation.

I will try to be more careful in my wording in the future. I appreciate the feedback and I hope you will keep it coming.

Will


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Sunday, 6 August 2017

How I became a climate skeptic.

Once upon a time, about 4 years ago, I was a climate believer. I believed the mainstream (IPCC) projections for climate change, and blamed most of it on carbon dioxide.

It seemed reasonable to decarbonize the energy system. I became a bit of a nuclear power advocate. I read books on nukes. I did introductory online courses on nuclear power. I noticed how the energy issue was totally partisan and divided right down the middle.

On one side were pro-nukes, on the other side the 'greens'. The greens were united along several lines. They:

  • opposed nuclear power
  • supported green issues
  • worried about global warming
  • were keen to reduce human energy use

For them, the debate was not about saving the planet by stopping carbon dioxide emissions. It was about saving the planet from the scourge of humanity.

The other side: pro-nukes was split. It included eco-modernists, conservatives, nuclear industry people, liberals and lefties.

I could not help notice that the news sources worrying about climate change were doing two things:

  1. opposing nuclear power
  2. greatly exaggerating climate change effects, and engaging in a little war against people they called 'deniers'.

Early on, I wanted nothing to do with any of these 'deniers'. They were right wing. They must be wrong. Right?

It slowly dawned on me that the only reasonable people refuting this climate alarmism in the news sources were the 'deniers'. What about all the reasonable people - those who accepted the mainstream IPCC analysis? Where were they in this debate? How come they weren't refuting the obvious over-exaggerations in the media?

The answer is that the 'mainstream' believe the establishment can only be goaded into action by exaggeration. So they stand by and let the hard-core green movement exaggerate. That was my first wake up call. My second wake up call came when I noticed the greens blaming global warming on nuclear power. What kind of good, ethically upright person, has any truck with that kind of politics. No me. That's the point when my pro-humanism kicked in and I dared to think the unthinkable. What if carbon dioxide was not much at fault for climate change? Then I looked at the evidence. The more evidence I looked at, the longer the term for the evidence: thousands, and even millions of years - the more I too turned into a 'denier' too. I have to call myself a skeptic.

I think CO2 has some effect on climate. I think it should warm climate mildly, but only a quarter to a third what IPCC say. I expect 0.6C per doubling of CO2. Q: What about the warming which has already happened? I hear you say. Surely that proves CO2 guilty? A: No.

  • Because we've seen no real warming for 18 years now. If it's 90% the fault of CO2, there cannot be a hiatus, but there is.
  • When you tell me what caused the Medieval Warm Period, then I'll believe there's such a thing as climate science. Till then it's climatology again.