Claim: What would have happened to the ozone layer if chlorofluorocarbons (CFCs) had not been regulated?

A new modeling based paper in Atmospheric Chemistry and Physics takes on that question directly.

Of course the result is another “saved the world” moment according to some:


[ Source: ]

I certainly don’t have a problem with reducing CFC’s, but Andrew Dessler’s comment speaks to the hero syndrome some of these scientists seem to have, which sometimes results in the “noble cause corruption of science” where the end justifies the means. Here is the paper abstract,  link to full text follows. 


Ozone depletion by chlorofluorocarbons (CFCs) was first proposed by Molina and Rowland in their 1974 Nature paper. Since that time, the scientific connection between ozone losses and CFCs and other ozone depleting substances (ODSs) has been firmly established with laboratory measurements, atmospheric observations, and modeling studies. This science research led to the implementation of international agreements that largely stopped the production of ODSs. In this study we use a fully-coupled radiationchemical-dynamical model to simulate a future world where ODSs were never regulated and ODS production grew at an annual rate of 3%. In this “world avoided” simulation, 17% of the globally-averaged column ozone is destroyed by 2020, and 67% is destroyed by 2065 in comparison to 1980.

Large ozone depletions in the polar region become yearround rather than just seasonal as is currently observed in the Antarctic ozone hole. Very large temperature decreases are

observed in response to circulation changes and decreased shortwave radiation absorption by ozone. Ozone levels in the tropical lower stratosphere remain constant until about

2053 and then collapse to near zero by 2058 as a result of heterogeneous chemical processes (as currently observed in the Antarctic ozone hole). The tropical cooling that triggers the ozone collapse is caused by an increase of the tropical upwelling. In response to ozone changes, ultraviolet radiation increases, more than doubling the erythemal radiation in the northern summer midlatitudes by 2060.

Full paper:


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Dodgy Geezer

I do have a strong suspicion about the whole CFCs issue.
As I recall, the chemical was banned on the grounds that lab tests and models showed that it could damage ozone – there were few actual observations in the field, and those which were done were inconclusive.
I also believe that the banning also came at a very convenient time for DuPont, which would otherwise have lost the patent on a very lucrative chemical, and seen other companies undercut it heavily.
I never gave the issue a lot of thought before, but it is so similar to the AGW exercise, that you have to wonder…

They took CFCs out of my asthma inhaler and replaced it with something less effective. I won’t forgive them for that.

Another modeling exercise….yawn.

george e. conant

cfc’s are too heavy and can not rise up, they sink rapidly, thump.


I’m extremely dubious about the whole ozone/CFC linkage. Too much reliance on lab tests and, once again, computer models, and precious little actual real world measurement. And once again based on a startlingly short observational period, we discovered the hole, and to my knowledge have no idea how natural or artificial it is. I recall reading one quote where one of the activists involved in banning CFCs saying it mattered little if it was an issue or not, that the real benefit was that banning CFCs served as a model for how to get world government type unified action accomplished. More of a trial run towards global socialist governance.

ozone depletion was another green scam. I’m sure lots of these green con artist made a fortune on it.

Henry Galt.

This is a precursor to “Ozone depletion over the Antarctic is responsible for record Antarctic sea-ice.” (Paper due late 2014) /sarc


The ozone hole hysteria calmed down, when some bright scientist realized that the holes might have been there long before discovered. The holes are located close to the magnetic poles and are affected by the stuff that the sun is throwing at us.
I might be wrong, but as far as I heard, CFCs are still produced and used i Asia …

Gerry Parker

Because they are so good at atmospheric modeling.


Aka, “messiah syndrome.” They are going to save all of us wallowing in original sin from ourselves. Because they are so visionary, doncha know.


Oh…so they proved it


I want my Freon-12 back!

The concentration of ozone in the Ozone layer is almost entirely dependent on the temperature, which is why we had ozone depletion in the 1970s.

Not long ago it was found that ozone amounts above 45km increased between 2004 and 2007 at a time of inactive sun.
The earlier observed decrease in ozone occurred during a period of active sun through solar cycles 21 to 23.
Ozone amounts control the temperature of the stratosphere and the height of the tropopause.
What has been happening since 2007 ?
The stratosphere appears to have stopped cooling around 2000 which is around the time that ozone began to recover and at the same time we descended from the active solar cycle 23 to the relatively inactive solar cycle 24.
Observations therefore suggest that the reduction of ozone and cooling stratosphere of the late 20th century was a consequence of high solar activity.
Our CFCs might have had some effect but it appears to be swamped by natural variability, rather like our emissions of CO2.

Jaakko Kateenkorva

Rubbish, if analyzed using physical chemistry instead of politics:
1) The sun’s UV-radiation forms ozone from dimeric oxygen molecules of the atmosphere during the day. Ozone is unstable molecule and degrades back into dimeric oxygen during the night. This is accentuated by solstice.
2) The molecular mass of even the simplest CFC (CCl3F) is significantly heavier than that of any other atmospheric gases. They more likely to stay on the round level than to float into the stratosphere.

sunshinehours1 says:
March 8, 2014 at 10:20 am
They took CFCs out of my asthma inhaler and replaced it with something less effective. I won’t forgive them for that.
This also increased the price of the inhalers from $5 to $50, effectively eliminating it for thousands, if not millions of poor asthma sufferers.
Just like biofuels, its euthanasia of the poor.

David L. Hagen

Solar & Halogenated gases affect Ozone and Global warming
See QB Lu for an alternative theory:

For global climate change, in-depth analyses of the observed data clearly show that the solar effect and human-made halogenated gases played the dominant role in Earth’s climate change prior to and after 1970, respectively. Remarkably, a statistical analysis gives a nearly zero correlation coefficient (R=^0.05) between corrected global surface temperature data by removing the solar effect and CO2 concentration during 1850-1970. In striking contrast, a nearly perfect linear correlation with coefficients as high as 0.96-0.97 is found between corrected or uncorrected global surface temperature and total amount of stratospheric halogenated gases during 1970-2012. Furthermore, a new theoretical calculation on the greenhouse effect of halogenated gases shows that they (mainly CFCs) could alone result in the global surface temperature rise of ~0.6 deg C in 1970-2002. These results provide solid evidence that recent global warming was indeed caused by the greenhouse effect of anthropogenic halogenated gases. Thus, a slow reversal of global temperature to the 1950 value is predicted for coming 5~7 decades. It is also expected that the global sea level will continue to rise in coming 1~2 decades until the effect of the global temperature recovery dominates over that of the polar O3 hole recovery; after that, both will drop concurrently. All the observed, analytical and theoretical results presented lead to a convincing conclusion that both the CRE mechanism and the CFC-warming mechanism not only provide new fundamental understandings of the O3 hole and global climate change but have superior predictive capabilities, compared with the conventional models.

Cosmic-Ray-Driven Reaction and Greenhouse Effect of Halogenated Molecules: Culprits for Atmospheric Ozone Depletion and Global Climate Change
QB Lu – International Journal of Modern Physics B, 2013 – World Scientific’
Now which model will prove to be more accurate?
PS See
Response by Qing-Bin Lu to “Qing-Bin Lu revives debunked claims about cosmic rays and CFCs”
at Climate Science Watch


I thought it was it was now known that the rate of photolysis was too high for the hole theory.


The so-called ozone hole was noted in the IGY, an early detente with the USSR that pooled science resources.
At one time the seasonal thinning of the ozone hole seemed to be well explained by the absence of sunlight and natural environmental factors.
The theory of CFC’s as a catalytic destroyer of ozone took hold in the 1970’s and led to a substantial ban of CFC’s over a number of years.
But the hole seems to be about the same as it ever was, raising questions about some of the current assumptions. But now ozone has also morphed into an explanation of ‘climate change’, which seems very convenient for something so far away, so difficult to measure and so subtle in its impacts……

Harry Passfield

It’s a model, so it must be true – in the same way that Kate Moss and Naomi Campbell (those well-known climatologists) are models – and everything they say is true – if not full of (or based on) ‘substance’…


Sorry to repeat this yet again but several years ago I asked a fundamental question of Cambridge university and the Max Planck institute.
The question was ‘ how do we know if there hasn’t always been an ozone hole prior to our ability to measure it from the late 1950’s?’
Both institutions admitted that they had no answer to the question and that it was possible holes had existed prior to imstrumental recordns but they thought the holes had become larger through mans actions.
Whether any means has since arisen to hind cast levels I don’t know.

So what is the effect of Ozone absorbing in the 9.6 micron band?

There still are more questions than asnwers in the whole CFC/ozone case…
One of the main steps in the chemical reactions leading to ozone depletion seems to be much slower than initially expected which doesn’t prove that CFC’s aren’t involved, but maybe at a much smaller rate than expected/modelled.
Further many of these reactions are taking place at the surface of ice crystals, at temperatures of minus 80°C, which only occurs seasonally around Antarctica and occasionally around the Arctic. It is there that most of the depletion happens during a few days/weeks (Arctic) to a few weeks/months (Antarctic). For the rest of the lower stratosphere there is little depletion as ozone is continually created (and destroyed) by UV light, mainly in the tropics. Despite the much thicker UV layer in the tropics, people (plants, animals) there receive 5 times more residual UV light in full sun than people at high latitudes, due to inclination and longer path through the atmosphere.
Thus the question remains where the reduction in ozone depletion / increase in UV would take place and where there would be health effect, if any…
BTW, skin cancer is mainly a question of choosing the right parents: if you live in Australia and your parents are aboriginals, there is near no chance to get skin cancer. But if you are a decendant of some pale skinned and red haired ancestors …
And indeed Dupont was quite willing to switch to HFC’s, for which they had brand new patents, while these for CFC’s were near expired…


The Montreal Protocol was the dress rehearsal for Global Warming. It worked so they thought the big one would… The link paper is 2009…????


ColAr says:
March 8, 2014 at 10:53 am
Very interesting. I have been trying to find a time series of measurements of chlorine in the upper atmosphere, but those data appear to be hard to find. However, there were several stories just this past December about there still being no signs that the CFC controls are having any effect, as here.

What if they find during this Sunspot minimum the whole gets larger for as pointed out in South CAROLINA, natural ozone production has dropped from critical to normal over the last several years. In other words, no ground level production of Ozone may allow it the layer to be depleted again and the hole will open up regardless of our legislation. Lack up adequate temperature, 82 degrees is needed for Ozone production at grass level. As the Earth cools through 2035, we should revisit this as often as Alarmists report on Polar bears and thawing Arctic Ice.


I have read the polar holes of the ozone layer are regarded as evidence of its depletion from human activity. It is known some industrial compounds (chlorofluorocarbons or CFC’s) chemically react with the O3 molecule of the ozone layer of the stratosphere thus depleting it and allowing heat to escape, effectively “countering” the dreaded man-made global warming effect.
IMHO there are more important explanations; the ozone layer is relatively thin (at 1 atm it would be less than 1/8 of an inch thick) and in a constant state of replenishment as well as depletion. 12 to 25 miles up high energy UV splits the O2 molecule into two atomic O1 molecules that then combine with O2 to form the unstable, temporary O3 ozone molecule which absorbs low energy UV.
It is my understanding the reasons for the changing polar ozone hole sizes are natural and include the seasonal lack of light in both areas, the atmospheric fluid dynamics at the polar vortices, the naturally occurring nitrous oxide molecules (lightening) and most importantly; the solar variances in UV radiation.
I have no skin in this game as I’m not a climate scientist. I’m just a curious guy and these are my thoughts. Apologies for the over simplification.

The reports I have acknowledge that the CFC/ozone push was a pilot to see if global regulations could be put into place to supposedly prevent an environmental catastrophe without having to prove anything. When it worked we got the AGW hype next.
The UN and who it funds have never made any pretenses that these models premised on ‘hard’ science are to gain political power to reshape economies and social and political structures. That has been consistent from the 70s on.
Now with the virtual reality worlds of gaming and the all-digital Common Core curricula Pearson (with Microsoft) and Amplify (a NewsCorp sub) have developed for the classroom, students’ beliefs about how the world works will be influenced by whatever beliefs the model creators have programmed into the software. With the constant refrain of pushing students to act and relying on biased institutions like the Smithsonian and National Geographic, it is likely the models will be propaganda. The game designers admitted as much at last year’s ISTE annual conference.

Funny how all these studies are invariably carried out by folks with a vested interest (often emotional) in the outcome. And where are the critical reviews that are always required?
The only thing that may have been avoided are disasters that only exist in the imaginary future
predicted by some model. Models need to be verified. It’s a simple as that.

Jaakko Kateenkorva says:
March 8, 2014 at 10:48 am
2) The molecular mass of even the simplest CFC (CCl3F) is significantly heavier than that of any other atmospheric gases. They more likely to stay on the ground level than to float into the stratosphere.
The molecular mass only plays a role as long as no mixing takes place, mainly by wind/turbulence. Once mixed in, even the heaviest molcules (scents e.g.) stay in the atmosphere for years if not rained out or chemically destroyed. See the Brownian motion effect…

Ed Fix

“hero syndrome”…
How else is a nerdy college professor ever going to get a chance to save the world?

Dennis Hand

I have always questioned this. Below is something I wrote to a liberal friend about this. I have never found anyone who could answer my questions.
The basic laws of physics say that lighter materials will float above heavier materials. So, if the atomic weight of a free Nitrogen molecule (N2) is 14 amu’s and that of a free Oxygen molecule (O2) is 16 amu’s and that of a free CFC-12 molecule is 64 amu’s, 4.57 time heavier than a Nitrogen molecule and 4 time heavier than an Oxygen molecule, the question to ask is how did something so heavy, comparatively, get up to the ozone layer, between 50,000 and 115,000 feet above us?
The next question to ask is, if the vast majority of CFC’s that were in use prior to the ban were in the Northern Hemisphere, why was the hole in the Ozone Layer that was so frequently referenced located over the South Pole and not the North Pole? It would seem that with air currents basically flowing from a polar region to the equator and back again, that the major portion of any destruction of the Ozone Layer would have been at the North Pole.
With the above questions comes the question are CFC’s really as dangerous as was stated? The mechanism that was stated as the cause of the breakdown was that once CFC’s were transported into the upper atmosphere cosmic rays broke down the CFC’s giving us a Chlorine ion that reacted in the following manner:
Cl· + O3 → ClO· + O2
ClO· + O3 → Cl· + 2 O2
This regenerative process of the Cl–– ion was stated to be very damaging because it could continue to react with Ozone ions over and over again. Being we are talking about the effect of a Cl–– ion, why has no one addressed the issue of the chlorine that evaporates into the atmosphere regularly from the chlorination of water systems, swimming pools, hot tubs, and other uses of chlorine. It would seem far more likely a mechanism for the above reactions, being that a chlorine molecule (Cl2) only weighs 34 amu’s and a chlorine ion Cl¬–– would only weigh 17 amu’s, much lighter than that of a CFC molecule and therefore more easily transported to the upper atmosphere.
Recently reported in the journal, that the key chemical reaction referenced above that was purported to have been the cause of the destruction of the Ozone Layer is almost 10 times weaker than assumed. As a result, at least 60% of the stratospheric ozone loss in recent decades can no longer be explained.
Back in the late 1980’s, during the heated discussion of the banning of CFC’s, there was an article on the back page of Discover magazine that basically said that the banning of CFC’s had nothing to do with the destruction of the Ozone Layer and everything to do with the expiration of the patents, which would allow anyone to produce CFC’s without paying royalties to the large chemical companies that held the expiring patents.
I don’t know if this is true, that corporations would take subversive actions to protect their profits, but a wise man one said that if you want to know the truth, follow the money.

John Testa

You know, during the winter in either the arctic or antarctic, there is a die off of some of the microscopic critters that tend to concentrate chlorine and bromine from seawater. This can release bromine and chlorine into the atmosphere during the winter in a region where the tropopause is closer to Earth’s surface and the storms can break through the tropopause sending vapors into the stratosphere. Work was done back in the ’80’s looking at gases in the stratosphere(about 36km) and bromine was one of the substances that was detected using neutron activation on the collected samples.


I still don’t understand the mechanism for fairly heavy CFC molecules to get from the Northern hemisphere to the South. What propelled them?

Some years ago when Dr. Tim Ball was a “regular contributor” of essays and other postings in Canada Free Press (CFP) he wrote an excellent essay on exactly this subject. I was sure I saved that article somewhere but I am unable to locate its whereabouts at the moment.
If Dr. Ball sees this, I do hope he re-posts his essay here. It is well worth a read. – Well, the said article was his work so really only he can do the/any “re-posting” in any case.

Janice Moore

“How else is a nerdy college professor ever going to get a chance to save the world?”
(asked wryly, by Ed Fix at 11:28am today, but, makes a powerful point incidentally)
Here’s how:
Dr. Frederick Banting — Insulin

My great-uncle died of Type I Diabetes (childhood onset) at about the same age about the same time Banting’s little friend died of it. I never got to meet him. Today, millions of families are spared the deep pain of losing a child. THAT is saving the world in meaningful sense.
And what a message of hope to all of us whose careers have, due to disappointment, followed the road “less travelled by” … . But for Banting’s medical practice never thriving, he likely never would have gone into that laboratory… . God truly does work in “mysterious ways.”
Always remember that. You ARE making a difference for good.
Each part of the body has its important work to do. (I. Corinthians 12:15-26). Every cell matters.

Janice Moore

Hi, O. H. Dahlsveen,
I believe his son DID post that essay, here:
I hope that is what you were hoping for,


O H Dahlsveen says:
March 8, 2014 at 11:53 am
See above @
David Ball says:
March 8, 2014 at 11:11 am

I am saying Stephen Wilde is right.
Ozone concentration (and that of peroxides, nitric/nitrous oxides) at the TOA are a function of solar activity which in its turn is governed by the movement of the planets. The more of these substances TOA, the more deflection to space, the less insolation of earth.
The whole CFC scare was exactly the same as the current carbon dioxide nonsense.

Janice Moore

Bart! One of the FINEST heroes of science I know.
According to the “great minds think alike” maxim — I must be pretty smart!

It was a load of garbage right from the start. Another scam and they were playing it for all it was worth – I’m sure funding was good for it – then environmentalism took centre stage and they all saw even more dollar signs and climbed on that bandwagon. I want to see them do jail time for it.

Jaakko Kateenkorva

Thank you Ferdinand for raising one of the AGW proponents’ favorite arguments, Brownian motion, in this context.
What bothers me with it is that atmosphere itself is not homogeneous. Most obvious example even in troposphere is that water vapor isn’t evenly distributed, but forms clouds. How is that possible if Brownian motion was a significant factor?
So, how can we take for granted that a wide family of CFC molecules mix randomly, float into a separate atmospheric layer and stay there? In addition CCl3F boiling point is 23 °C and it would go through phase transition well before reaching the stratosphere.

wasn’t there an article on this site a few months back showing the holes have been there long before CFC?

michael hart

If only they would stick to forecasting the past. They would then get to be approximately and smugly correct, and the rest of us could get on with more important things without having to listen to their failing forecasts of the future.


Doesn’t “crying wolf” imply deceptive alarmism?

James Roots

Did the whole world ban cfcs? Or just USA?
Find it hard to believe that the ban in the USA could save the world. Like coal. US is trying to reduce use of it, while the rest of the world increases it’s use of coal.
Have to admit I am ignorant on this issue, it was way before my time.


Does anyone recall research done, perhaps by a Russian scientist in the last 10 years or so, which concluded that the basic reaction rate of the key equation was off by an enormous amount? As such, to achieve the claimed reductions in ozone, it would have taken an enormously long time.
If accurate, the research showing the slower rate meant the claims of the Montreal Protocol could not have been true. Looked for it recently, but didn’t see it.
Perhaps some could post a link, so we could review those findings too. Commentary on that work would also be appreciated.

Brian H

What would have happened without the CFC ban is exactly the same as what did happen. An empty but very expensive gesture. Un-ban Freon!