Ozone at lower latitudes is not recovering, despite Antarctic ozone hole healing

From IMPERIAL COLLEGE LONDON

The ozone layer – which protects us from harmful ultraviolet radiation – is recovering at the poles, but unexpected decreases in part of the atmosphere may be preventing recovery at lower latitudes.

Global ozone has been declining since the 1970s owing to certain man-made chemicals. Since these were banned, parts of the layer have been recovering, particularly at the poles.

However, the new result, published today in the European Geosciences Union journal Atmospheric Chemistry and Physics, finds that the bottom part of the ozone layer at more populated latitudes is not recovering. The cause is currently unknown.

Ozone is a substance that forms in the stratosphere – the region of the atmosphere between about 10 and 50 km altitude, above the troposphere that we live in. It is produced in tropical latitudes and distributed around the globe.

A large portion of the resulting ozone layer resides in the lower part of the stratosphere. The ozone layer absorbs much of the UV radiation from the Sun, which, if it reaches the Earth’s surface, can cause damage to DNA in plants, animals and humans.

In the 1970s, it was recognised that chemicals called CFCs, used for example in refrigeration and aerosols, were destroying ozone in the stratosphere. The effect was worst in the Antarctic, where an ozone ‘hole’ formed.

In 1987, the Montreal Protocol was agreed, which led to the phase-out of CFCs and, recently, the first signs of recovery of the Antarctic ozone layer. The upper stratosphere at lower latitudes is also showing clear signs of recovery, proving the Montreal Protocol is working well.

However, despite this success, scientists have today revealed that stratospheric ozone is likely not recovering at lower latitudes, between 60?N and 60?S (London is at 51?N), due to unexpected decreases in ozone in the lower part of the stratosphere.

Study co-author Professor Joanna Haigh, Co-Director of the Grantham Institute for Climate Change and the Environment at Imperial College London, said: “Ozone has been seriously declining globally since the 1980s, but while the banning of CFCs is leading to a recovery at the poles, the same does not appear to be true for the lower latitudes.

“The potential for harm in lower latitudes may actually be worse than at the poles. The decreases in ozone are less than we saw at the poles before the Montreal Protocol was enacted, but UV radiation is more intense in these regions and more people live there.”

The cause of this decline is not certain, although the authors suggest a couple of possibilities. One is that climate change is altering the pattern of atmospheric circulation, causing more ozone to be carried away from the tropics.

The other possibility is that very short-lived substances (VSLSs), which contain chlorine and bromine, could be destroying ozone in the lower stratosphere. VSLSs include chemicals used as solvents, paint strippers, and as degreasing agents. One is even used in the production of an ozone-friendly replacement for CFCs.

Dr William Ball from ETH Zurich and PMOD/WRC Davos, who led the analysis, said: “The finding of declining low-latitude ozone is surprising, since our current best atmospheric circulation models do not predict this effect. Very short-lived substances could be the missing factor in these models.”

It was thought that very short-lived substances would not persist long enough in the atmosphere to reach the height of the stratosphere and affect ozone, but more research may be needed.

To conduct the analysis, the team developed new algorithms to combine the efforts of multiple international teams that have worked to connect data from different satellite missions since 1985 and create a robust, long time series.

Dr Ball said: “The study is an example of the concerted international effort to monitor and understand what is happening with the ozone layer; many people and organisations prepared the underlying data, without which the analysis would not have been possible.”

Although individual datasets had previously hinted at a decline, the application of advanced merging techniques and time series analysis has revealed a longer term trend of ozone decrease in the stratosphere at lower altitudes and latitudes.

The researchers say the focus now should be on getting more precise data on the ozone decline, and determining what the cause most likely is, for example by looking for the presence of VSLSs in the stratosphere.

Dr Justin Alsing from the Flatiron Institute in New York, who took on a major role in developing and implementing the statistical technique used to combine the data, said: “This research was only possible because of a great deal of cross-disciplinary collaboration. My field is normally cosmology, but the technique we developed can be used in any science looking at complex datasets.”

###

The paper: ‘Evidence for a continuous decline in lower stratospheric ozone offsetting ozone layer recovery’ by William T. Ball et al. is published in Atmospheric Chemistry and Physics.

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GREGORY in Houston
February 7, 2018 8:05 am

Until increased UVA & UVB radiation can be shown to have occurred, it matters not what the ozone layer does. The lack of screams from greens re: no UV data speaks volumes.

Reply to  GREGORY in Houston
February 7, 2018 8:19 am

Ozone does many things besides stopping UV. It is also a great deal responsible for stratospheric temperature and pressure variations (geopotential height), and might be involved in polar vortex stability. Finding out what is going on with ozone is of great importance. We still have a lot to learn about ozone role in weather and climate change.

GREGORY in Houston
Reply to  Javier
February 7, 2018 8:28 am

Javier, “great deal” and “might” mean nothing. Explain with numbers and examples.

Reply to  GREGORY in Houston
February 7, 2018 9:03 am

Well, read the literature if you want the numbers. But where do you think all the energy that those UV photons carry is deposited when they are stopped at the ozone layer? And how much energy do you think it takes to warm the rarefied stratosphere? And how much does pressure respond to that UV-dependent warming?
What we don’t know could fill libraries, but what we do know is sufficient to know how important ozone is to the planet.

D. J. Hawkins
Reply to  Javier
February 7, 2018 9:32 am

So how is ozone formed? Why, some UV radiation smacks an O2 molecule, creates a radical, and that radical sucks up another O2 to form O3. We can’t run out of ozone unless we run out of UV. Hint to researchers: If you’re not finding it where you expect, look elsewhere. Or, consider, even if TSI is fairly invariant, the UV component can get a 10X swing in it IIRC. What’s it been doing lately?

MarkW
Reply to  Javier
February 7, 2018 9:46 am

Back in the days of the great ozone scare, we were told that the amount of UV that the sun generated was pretty close to invariant. Therefore any change in the amount of UV reaching the ground had to be man’s fault.

rogerthesurf
Reply to  Javier
February 7, 2018 11:19 am

In NZ the ozone hole has been taken seriously. Sunblock is considered essential and sun bathing is frowned on,
Its true that the air here is very clear by world standards (so we are told) and therefore the sun is stronger. This also shows up poor quality paint on ones house. Difficult to stop fading chalking and peeling at the best of times.
However the reservations I have about the Ozone hole is that the formation of it was not observed, it was discovered almost by accident.in the 1980’s and there is no previous record of Ozone depletion or otherwise in the history of the earth. In short, no one has the slightest idea how long the Ozone hole has been around. A million years maybe?
Well who gains, Let me see. 1. Sun block manufacturers and retailers. Well with my European skin I suspect I need it anyway, ozone or no ozone. 2. Suppliers of refrigerants – All refrigerators and vehicle air conditioning must have non CFC refrigerant. 3. Scientists who score funds from authorities in order to study this phenomena.
I for one accepted all the above as fact, but now in this AGW era, the similarities are too striking. Was and is the ozone hole a precursor of the Global warming theory?. Without historical records there is absolutely no proof that the ozone hole is man made.
With AGW we do have historical records but these have been either ignored or treated as irrelevant, but the hype goes on and like the ozone hole, AGW is both suspect, both scientifically and politically.
The ozone hole, I suspect would never meet Karl Poppers requirements for a hypothesis any more than our current AGW debacle.
Cheers
Roger
http://www.thedemiseofchristchurch.com

Reply to  rogerthesurf
February 7, 2018 4:21 pm

I was talking about the current decline in ozone that is being measured. I have no idea if the ozone hole is man-made and is caused by human chemicals, or if it is due to the peculiarities in stratospheric ozone transport.
What I do know is that stratospheric ozone is extremely important and therefore it needs to be researched and monitored intensively.

GREGORY in Houston
Reply to  Javier
February 7, 2018 11:59 am

Nice dodge, Javier. Of course it doesn’t matter what I “think.” What matters is the practical effect – which is essentially zilch. Since you asked the questions, you must know the answer. Tell us… or tell us that we don’t know, but it “might” matter a “great deal,” so just in case, we need to change our AC refrigerant every 5 years…. and make sure the new refrigerant is not back-compatible with the previous fad-driven compound.

Reply to  GREGORY in Houston
February 7, 2018 4:15 pm

If I knew the answer I would be publishing it in a scientific journal, wouldn’t I?
So when did I talk about refrigerants?

zazove
Reply to  Javier
February 7, 2018 5:08 pm

Javier, interesting. It seems expressing a natural curiosity to “Finding out what is going with ozone…” has pushed all kinds of odd buttons.

Iurockhead
Reply to  Javier
February 7, 2018 5:13 pm

Rogertheserf, not the 1980’s. That’s when it was first observed from a satellite. Gordon Dobson first observed and described it in 1956. Thus the measurement of strat ozone in Dobson Units.
[‘strat ozone” is stratospheric ozone ? .mod]

higley7
Reply to  Javier
February 8, 2018 6:53 am

Remember that we now know that it is solar UV and nitrogen gas, not CFCs, that exacerbated the Antarctic ozone hole. We need to recognize that solar UV interacting with oxygen gas also makes ozone and, with solar UV output dropping, it is no surprise that stratospheric ozone would decline. Ozone at lower latitudes is made and destroyed constantly, probably by a number of processes, and its replenishment by UV and oxygen gas logically will drop off with decreasing solar UV output. There is no evidence of increased breakdown, and decreased production has to be considered. It’s the Sun.

Reply to  higley7
February 8, 2018 9:44 am

It’s the Sun.

Your conviction is no guaranty. You may be right, but science requires evidence.

Clyde Spencer
Reply to  GREGORY in Houston
February 7, 2018 8:23 am

Exactly! Once again, the alarmists say, “The potential for harm in lower latitudes…” but provide no data that the ‘potential’ is actually happening.

Bill Powers
Reply to  Clyde Spencer
February 7, 2018 10:14 am

Nor explain what the hell could be done about it. Oh wait. Aside from Government Intervention with regulations and laws degrading our quality of life and increasing our cost of living with no verifiable evidence that this intervention into our lives will have any affect on the manufactured hypothesis.
It will even be reported that in fact all this posturing by world governments will not fix the problem but we must do something to delay the consequences. All the while, those lawyers swimming in the lobby swamp will get richer by transferring middle class billions to the Crony Capitalists using campaign contributions and kick backs to the puppet politicians.
This always bares repeating when science meets government: ‘The whole aim of practical politics is to keep the populace alarmed (and hence clamoring to be led to safety) by menacing it with an endless series of hobgoblins, all of them imaginary.” H.L. Mencken
It is a Universal Law not a theory and Mencken was a genius.

Dr. S. Jeevananda Reddy
Reply to  GREGORY in Houston
February 7, 2018 4:11 pm

To destroy ozone in the presence of chlorine-bromine, needs lower temperatures for chemical reaction. From tropopause in lower stratosphere the temperature increases with the height. Thus, the only possibility to show decreasing trend in ozone content in the said zone may be due to observational techniques used to measure ozone — past, present. Ozone has daily & seasonal variations.
Dr. S. Jeevananda Reddy

aleks
Reply to  Dr. S. Jeevananda Reddy
February 8, 2018 3:27 pm

Absolutely correct remark about the temperature effect. Reaction of ozone decomposition is very sensitive to temperature: https://www.lenntech.com/library/ozone/decomposition/ozone-decomposition.htm

February 7, 2018 8:06 am

Forgive me, but I don’t believe a word these pseudo-scientists write (or say) these days.

Marty
Reply to  Patrick Wood
February 7, 2018 11:10 am

Exactly right, Patrick. I don’t know if they are right or not. Maybe what they are saying is true and they are pointing out a significant danger. But after all the lies and all the exagerations about global warming, can we trust these people? Wouldn’t it be ironic if this time the danger were actually real and no one believed them?

Roger Knights
Reply to  Marty
February 7, 2018 11:20 am

Right–eventually there WAS a wolf.

February 7, 2018 8:18 am

It’s news to me that there was any ozone loss other than at the poles. I don’t trust a word they say…..

M.W. Plia.
February 7, 2018 8:23 am

The polar holes of the ozone layer were once regarded as evidence of its depletion from human activity, I was not aware this nonsense was still one of the chapters in the man-made global warming scary narrative.
We all know some industrial compounds (chlorofluorocarbons or CFC’s) chemically react with the O3 molecule of the ozone layer of the stratosphere thus “depleting” it. But there are other 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 now understood, or should be understood the main reasons for the changing polar ozone hole sizes are natural and include the seasonal lack of light, the atmospheric fluid dynamics of the polar vortices, fluctuations with naturally occurring nitrous oxide and most importantly, the solar variances in UV radiation.

icisil
February 7, 2018 8:26 am

Can anyone else think of other things that we need to worry about?
Also, has anyone considered the fact that increased surveillance gives the appearance of new happenings? And that increased funding increases surveillance (rhetorical questions of course)

MarkW
Reply to  icisil
February 7, 2018 9:48 am

More evidence that the CO2 scare is running out of gas.
They are trying to resurrect their last successful scare.

Gordon Pratt
February 7, 2018 8:27 am

Claim: The upper stratosphere at the poles is showing signs of improvement proving the Montreal protocol is working well.
Does the decline in ozone in the stratosphere at lower latitudes prove the Montreal Protocol is not working?
And why does climate “science” so often require higher food prices, in this case a rise in refrigeration costs?

MarkW
Reply to  Gordon Pratt
February 7, 2018 9:49 am

Anything good that happens was caused by us.
Anything bad that happens was caused by you.
Don’t worry about trying to prove it.

TonyL
February 7, 2018 8:28 am

They find a result in existing data which has never been reported before.
How was it done?

the team developed new algorithms to combine the efforts of multiple international teams

and

developing and implementing the statistical technique used to combine the data

Oh, Look.
They tortured the data until it confessed. How original.

Gary Pearse
February 7, 2018 8:39 am

These sorts of confounding things point to how dangerous the confident scientists are who are driving policy. It has bothered more thoughtful people that their never was a measure of ozone before the late 1950s when the ozone hole was discovered. It was simply assumed to have been damage by humans. The “recovery” is also suspect because we dont really know what kind of variability there is. A year ago, NASA was saying something about the persistence of the hole over the south polar area. Ive pointed out a data issue that even WUWT commenters have ignored for about 10 years – mentioned it periodically and I’ll mention it again. When you have a pronounced ozone hole, the peripheral ring of the hole shows a large thickening of the ozone outside the hole – like a rollneck sweater collar. My contribution has been that a measure of this redistribution of ozone may show that their is no loss at all. Here is an image of what I mean:
https://earthobservatory.nasa.gov/IOTD/view.php?id=82596
The ozone hole has ~200DB units the “collar” has up over 500DB units and it extends thinning into 300DB going into the Temperate Zone.
Surely some adroit electronic graphic person could quantify all this and see if it is all simply redistribution. At least it would be gratifying to have one scientists say something here in comments. It gets lonely hear sometimes.

Clyde Spencer
Reply to  Gary Pearse
February 7, 2018 2:05 pm

Gary,
I’m aware of the anomalous ozone highs outside the circumpolar vortex. (Almost all the NASA illustrations show it!) And, like you, I have mentioned it more than a few times when the topic of ozone comes up. However, no one has latched onto the significance of the ozone being produced in the tropics and transported poleward by the Brewer-Dobson cells. It results in a disruption of replenishment of ozone inside the (Winter) vortex, until such time as the vortex breaks up (Spring). Then, there is stratospheric air, enriched in ozone, able to move in and mix with the depleted air. Most of this activity takes place when the sun is low on the horizon, therefore has a large footprint (small flux), and the sun’s rays pass through a long slant-range path that encourages scattering and absorption of the UV. By the time that the sun gets high enough in the sky to provide intense sunlight, the vortex is usually broken up and the ozone is back to about where it should be, with annual variations in the timing.

Gary Pearse
Reply to  Clyde Spencer
February 7, 2018 2:53 pm

Thank you Clyde. It’s nice to be talking to someone about this. I also commented that O2’s paramagnetic susceptibility is not insignificant (liquid oxygen is fairly magnetic), whereas ozone is diamagnetic (pushed away from a strong field). Some have commented on my idea but advise that the forces are not strong. Nevertheless, there would be a (small) tendency for pushing ozone away and magnetic attraction of O2 + the added vacuum pull with vacation of ozone. Incidentally, other gases like Nitrogen and Noble gases are also diamagnetic. A way to test the significance or insignificance of the idea would be to see if there is a Noble gases, Nitrogen, Methane and CO2 hole at the the pole as well (maybe replaced by higher Oxygen when the Ozone hole is present.

Tom in Florida
February 7, 2018 9:17 am

““The finding of declining low-latitude ozone is surprising, since our current best atmospheric circulation models do not predict this effect. Very short-lived substances could be the missing factor in these models.”
I am shocked, shocked I say, to learn that there is an admission of models being wrong with missing factors.
I wonder if they have a refund clause for those models?

February 7, 2018 9:18 am

Grantham Institute? Like Grantham Institute of Bob Ward?

February 7, 2018 9:29 am

Clearly the justification for the Momtreal Protrocol was based on wrong science and rhe banning of Freon and other similar gases has done nothing to imptove the ozone situarionb intens of decades. . The Montreeal protocol should be voided with all its sneak additions and Freon (qnd similar) users should be liberated from fake science.

Art
February 7, 2018 9:38 am

As long as they insist that the Antarctic ozone hole was a result of human activity that only appeared in 1985, that variations in ozone levels are only due to our emissions of one sort or another, their research can not arrive at any factual conclusions – it’s all built on a false premise.

MarkW
February 7, 2018 9:44 am

Ozone is “failing to recover” primarily because CFCs never had anything to do with the alleged decline.

Har old
February 7, 2018 9:53 am

Was there ever an ozone hole at the north pole ? Anyone has the numbers ?

Art
Reply to  Har old
February 8, 2018 10:02 am

It’s long been known that there is a thinning of ozone at the north pole in winter, but it doesn’t get as severe as the south pole because the weather pattern is different. The south polar vortex forms every winter and prevents ozone from flowing in from northerly latitudes. That weather phenomenon doesn’t happen at the other end of the earth, so ozone comes in.

aleks
Reply to  Har old
February 8, 2018 4:20 pm

Data about ozone layer over the North pole are given here:http://www.theozonehole.com/arcticozone.htm
This value (~250 DU, or number of ozone molecules per sq.m) “is comparable to thickness of this layer in the tropics” but much more than over the South Pole. Please, note: the main sources of CFCs are in Europe and North America. So, is it more easy for CFC to reach Antarctica than Arctic?

dodgy geezer
February 7, 2018 9:59 am

It’s TRUMP! Or CHEMICALS!
So long as we remove all chemicals from modern living, we won’t have a problem. Mainly because, without chemicals, we won’t be able to run a technological civilisation with sufficient capability to measure ozone anywhere….

Hugs
Reply to  dodgy geezer
February 7, 2018 12:00 pm

Trump has been planning to remove ban on genetically modified crops being fed dihydrogen monoxide, DHMO. GMO grown with DHMO is at least 160% more poisonous to humans. DHMO fertilized GMO potatoes’ fruit has been proven to be toxic to liver, killing the victim slowly and painfully. Act now to stop this madness! #bandhmo #bangmo #bantrump

February 7, 2018 10:03 am

What happens to all of the Ozone generated by the hundreds of thousands of miles of high voltage transmission lines?

Hugs
Reply to  usurbrain
February 7, 2018 12:01 pm

Reacts with dirt in air.

David Ashton
Reply to  usurbrain
February 9, 2018 12:32 pm

It has a half life of about 10 hours in 50% humid air at 20°C.

Tom Anderson
February 7, 2018 10:09 am

Then there is Connolly and Connolly who in a paper posted at this site (https://wattsupwiththat.com/2017/08/22/review-and-summary-of-three-important-atmospheric-physics-papers/) pointed out several problems with the classical explanation for the formation of ozone, called the Chapman mechanism. They said, as I understand it, that ultraviolet light (UV) striking oxygen molecules will split them into individual oxygen atoms. They then speculate that some of these would combine with nearby oxygen molecules and form ozone.
Classical theory is that “ozone heating” reverses the extra energy in the tropopause and stratosphere that reverses the negative lapse rate. The argument is that ozone absorbs UV light from the sun and radiates heat which warms the tropopause and stratosphere. Yet, the tropopause stays in place during Arctic and Antarctic winters when there is no sunlight.
The first problem, they write, is the requirement for a great deal of energy to break a diatomic oxygen molecule’s bonds. Further, if the Chapman mechanism were the only mechanism forming ozone, why would ozone concentrations, in the Northern Hemisphere, be the highest in the Arctic in the spring rather than at the equator, which receives the most solar UV yet has much lower ozone concentration than in the Arctic?
Given these contradictions, Connolly and Connolly advanced an alternative mechanism. It is that ozone is formed directly from tropopausal oxygen multimers, which requires much less UV radiation than does the Chapman process. The idea that multimers make ozone easier to form, is only one of the potential impacts, they suggested, of possible multimer formation in the tropopause and stratosphere. Multimer formation may also influence tropospheric weather as discussed in Connolly and Connolly paper 2 in the post. They claim their idea allows ozone to form more easily and with less energy, while it providing additional energy during the Arctic and Antarctic winters when there is no sunlight for months
Their paper illustrates a multimer of eight oxygen atoms and four oxygen molecules transformed into two ozone molecules and one regular oxygen molecule. While the process requires abundant multimers to work, it requires solar less energy. They further hypothesize that the formation of the multimers themselves can occur without sunlight and the formation process releases heat of formation, warming the atmosphere at the tropopause.

Tom Anderson
February 7, 2018 10:12 am

“Classical theory is that “ozone heating” reverses the extra energy in the tropopause and stratosphere that reverses the negative lapse rate”.
Sorry, no that couldn’t be right. ‘Ozone heating,” I think, provides the extra energy in the tropopause that reverses … etc.
My apologies.

February 7, 2018 10:26 am

“The finding of declining low-latitude ozone is surprising, since our current best atmospheric circulation models do not predict this effect. Very short-lived substances could be the missing factor in these models.”
Models again! Quelle surprise! “Very short-lived substances could be the missing factor”. Right-o!
Let’s all jump to a conclusion, based on no credible evidence, just like they did when they banned CFC’s.
Fearless Conclusion:
THE DECLINE IS LOW-ALTITUDE OZONE IS CAUSED BY METHANE EMISSIONS FROM HUGE STEAMING MOUNTAINS OF GLOBAL WARMING BULLSH!T.

David L. Hagen
February 7, 2018 10:27 am

For an alternate Ozone theory see QB Lu.
New Theories And Predictions On The Ozone Hole And Climate Change by Lu, Qing-bin, 2015 World Scientific 305 pp

This monograph reviews the establishment of new theories of the ozone hole and global climate change, two major scientific problems of global concern. It provides a comprehensive overview of the author’s work including significant discoveries and pioneering contributions, such as the discovery of extremely effective dissociative electron transfer reactions of chlorofluorocarbons (CFCs) adsorbed on ice surfaces and its implications for atmospheric ozone depletion; the proposal of the cosmic-ray-driven electron-induced-reaction (CRE) theory for the ozone hole; the predictions of 11-year cyclic variations in polar ozone loss and stratospheric cooling; the discovery of the nearly perfect linear correlation between CFCs and global surface temperature; the proposal of the CFC theory for modern global warming; the discovery of greenhouse-gas-specific climate sensitivity and the parameter-free calculation of global surface temperature change caused by CFCs; the prediction of global cooling; and so on.Unlike conventional atmospheric and climate models, the author’s theoretical models were established on robust observed data rather than computer simulations with multiple parameters. The new theories have shown the best agreements with the observed data within 10% uncertainties. This book highlights the scientific understandings of the world-concerned problems from the unique point of view of a physicist who seeks theories with great simplicity and superior predictive capacity.This book is self-contained and unified in presentation. It may be used as an advanced book by graduate students and even ambitious undergraduates in physics, chemistry, environmental and climate sciences. It is also suitable for non-expert readers and policy makers who wish to have an overview of the sciences behind atmospheric ozone depletion and global climate change.

Michael Keal
Reply to  David L. Hagen
February 8, 2018 11:38 am

“the predictions of 11-year cyclic variations in polar ozone loss and stratospheric cooling” Solar cycle?

David L. Hagen
Reply to  Michael Keal
February 9, 2018 8:34 am

Michael Keal Yes QB Lu models cosmic radiation/solar cycle impacts.

February 7, 2018 11:01 am

I don’t see a graph so I cannot determine what is correct.
here is my data from a place in Switzerland
clearly the trend is up from 1995
in line with the Gleisberg SCcomment image
I also saw on a site that is the worst in terms of SS that the ozone in the SH is also going up since 1995.
Note that due to individual changes within the short term 11 & 22 SC’s you cannot look at ozone over a smaller period than 87 years….
(He that understands this is a clever man)

February 7, 2018 11:21 am

This how you do propaganda. You make a statement like this (from above text of article):
“Global ozone has been declining since the 1970s owing to certain man-made chemicals. ”
Good formed disinformation campaigns take a data driven result (some objective truth), and then wrap a conjecture or even an outright lie around around it. Then if someone objects, you try to cut them off and claim they don’t believe in the data (that ozone has declined). After that your naive audience is forced to accept your false (or unproven) assertion (owing to certain man-made chemicals) and then are led down the path to controlling their beliefs.
As you lead them down that path, then any man-made chemical you can name they are willing to accept as part of the “science truth.” (aliphatic paint thinners in this case of this study)

Reply to  Joel O’Bryan
February 7, 2018 12:06 pm

By George, I think you’ve got it!
The decline in the birthrate caused by male fear of prosecution for ‘inappropriate touching’ by rampant feminists, is of course a great driver towards Islamic immigration as the only way to provide new plebs to steal from.
Are you an Islamic immigration denier then?
Shame on you!

February 7, 2018 12:07 pm

From an analytical standpoint, I find their concerns about understanding the “why” laughable. They give 3 possible explanation in their Conclusions section.
1. “part of the tropical and subtropical (<30◦) lower stratospheric decline may be linked to a greenhouse-gas-related BDC acceleration."
2. "a rise in the tropopause (Santer et al., 2003), due to the warming troposphere, could lead to a decrease in ozone at mid-latitudes …"
3. "an acceleration of the lower stratosphere BDC shallow branch (Randel and Wu, 2007; Oman et al., 2010) might increase transport of ozone-poor air to the mid-latitudes from the tropical lower stratosphere."
Then they try to pin the lower-stratospheric ozone decrease "on additional chemically driven contributions from increasing anthropogenic and natural very-short-lived substances (VSLSs) containing chlorine or bromine." They offer no evidence other than a cherry-picked modelling study done by another group and published in 2015 (note 2 below). They completely fail to discuss the most obvious mechanism.
For your consideration:
#1. Their own statement in the study abstract: "Ozone forms in the Earth’s atmosphere from the photodissociation of molecular oxygen, primarily in the tropical stratosphere. "
#2. Photodissociation of O2 to form O3 is due to the incident high-levels of UV arriving from the sun.
#3. It stands to reason any secular decline (over the period of study )in arriving UV would decrease O3 production.
#4. The solar F10.7 radio flux is an accurate proxy for solar UV flux.
#5: The F10.7 record:
http://www.spaceweather.gc.ca/auto_generated_products/solradmon_eng.png
Seems pretty clear to me that UV from the sun has been declining since the 1970's. The most likely mechanism is one that makes the fewest assumptions and can explain the observations, and like with climate change itself, the answer likely lies in the sun.
Note 1: BDC = Brewer–Dobson circulation
Note 2. Hossaini, R., Chipperfield, M. P., Montzka, S. A., Rap, A., Dhomse,
S., and Feng, W.: Efficiency of short-lived halogens at influ-
encing climate through depletion of stratospheric ozone, Nat.
Geosci., 8, 186–190, https://doi.org/10.1038/ngeo2363, 2015.

Reply to  Joel O’Bryan
February 7, 2018 1:04 pm

Having used both a cream seperater & oil cleaner, same action as the cream seperater, its obvious that the spin of the earth will cause a thinning of the gases over both poles.
When we come across two headed penguins in the antartic i will say that we may have a problem.
Its all natural, but wait, its a ” cause “.
Mje

February 7, 2018 1:22 pm

When you attack things which are not the cause of the problem, the problem is very little affected. After some serious research and science, you might be in a position to do something that actually tackles the underlying problem.

Hivemind
February 7, 2018 1:56 pm

“…the application of advanced merging techniques and time series analysis has revealed a longer term trend of ozone decrease in the stratosphere at lower altitudes and latitudes.”
This sounds suspiciously like the special and unique statistical techniques that allowed climate “scientists” to pull a hockey stick out of temperature records. In fact, even from a sequence of random numbers. Call me a cynic, but I was never convinced that the ozone hole was created by CFCs. It appears to be a completely natural result of the conditions at the south pole.

stephana
February 7, 2018 3:05 pm

How do they know that the ozone hole is healing? It was there the first time that they looked, and then they assumed that it had to be man made. Maybe the hole is supposed to be there, and if it closed it portends doom.

Gary Pearse
February 7, 2018 3:54 pm

We live on a saltwater planet with chlorine, bromine, HCl in sea spray from waves pounding beaches and cliffs and wind blown from wave crests and hurricane conduits to the stratosphere. We have volcanoes and volatiles from plants, forests making chemical soup of the atmosphere, lightning strikes probably cleaving salt into sodium hydroxide/hydrogen and Cl gas.
Here is a Springer link article on analysis of volcanic gases
https://link.springer.com/article/10.1007/BF02596953
“The determination of H2O, CO2, SO2, SO2, S2, H2S, HCl, HF, H2, N2, O2, CH4, CO and NH2 is described.”
And: http://volcano.oregonstate.edu/book/export/html/393 .
“Once the tube is inserted into the fumarole or vent, the gases will bubble through the solution and gases like CO2, H2S, SO2, HCL and HF will dissolve into the liquid. Those gases that remain like N2, O2, H2, CO and He will rise further and collect in the headspace of the bottle.”
It seems to me that a hot mix of these gases, the very reactive HCL and HF (fluorine is the most electronegative element in the periodic table and therefore reacts with almost everything. It requires special plastic containers – it dissolves glass, rock, metals, etc. CO is similarly reactive – so you have all the ingredients in a very reactive hot gaseous state. I believe it would be a questionable presumption that no natural sources of CFCs exist as every article first in line on the internet tells us. And you know these “popular” articles are crazy-glued into place by nets of metadata. If you type whatsupwiththat in many search engines, the first place is Wikipedia – using the name and the header from WUWT and describing it as a site for science deniers! All the controversial stuff is voraciously guarded against employing sophisticated meta data algorithms to keep you away from what you are looking for.

bitchilly
February 8, 2018 12:44 am

the key words in the piece are “more research may be needed”. in other words funding may be running short and they want more of your money.

Brett Keane
February 8, 2018 12:50 am

Watching the quietening of the sun esp UV-wise, we expect lower ozone production, but also lower destruction. The real story is likely to be quite different. The whole tale is a fable. Their mechanism lacks the right energetics for the proposed reactions. Here in the SH the claimed hole over NZ never happens, but they spin the scare story anyway.
Of course, the whole process is misdescribed, with shortages restricted to the winter polar darkness. Relax, the penguins and polar bears are safe from sunburn.

aleks
February 10, 2018 3:09 pm

Remarks about some statements in the article.
“Ozone is the substance that forms in the stratosphere”. Incorrectly. Ozone forms also in the troposphere as a result of lightning discharges and (more important) of photochemical reactions: https://en.wikipedia.org/wiki/Tropospheric_ozone. Processes in the stratosphere can not be considered without taking into account the role of tropospheric ozone.
“It (ozone) is produced in tropical latitudes and distributes around the globe”. Wrong. Ozone can form in the stratosphere wherever there is available UV-radiation of sufficient energy. Formation of ozone stops only in polar regions during polar nights.
“In 1970s, it was recognized that chemicals called CFCs, were destroying ozone in the stratosphere”. The word “recognized” is irrelevant here, because M.Molina and F.Rowland (1974) did not prove experimentally chemical reaction between CFCs and O3 in the stratosphere, they “have attempted to calculate the probable sinks and lifetimes for these molecules” (CF2Cl2 and CFCl3). https://unep.ch/Ozone/pdf/stratopheric.pdf These authors considered raising CFCs to the stratosphere due to vertical diffusion, but did not take into account gravity (both substances are 4 – 4.5 times heavier than air) and the fact what CFCl3 to liquid state already at the temperature +23.6oC.
About the very short living substances. The most important are CHBr3 and CH2Br2 (boiling points are 149 and 97oC). Is it possible for them to reach the stratosphere?
Also, bond energy for C-Br is 276 kJ/mole, it corresponds to maximum wavelength for breaking bond of 434 nm. It means that VSLS can be destroyed in the lower troposphere, their effect on stratospheric ozone if doubtful.

davidbennettlaing
February 15, 2018 11:21 am

Anybody notice that the time series of global atmospheric equivalent chlorine bears an uncanny resemblance to the time series of global temperature? Anybody stop and think that ionizing UV-B, which is well-known to produce severe sunburn and genetic alterations could also be a potent source of global warming? Anybody (besides me and Peter Ward) stop and think that the main forcing agent in global warming isn’t CO2 at all but chlorine from CFCs and non-explosive (non-erosol-producing) volcanoes?
It’s not CO2, stupid; it’s CHLORINE!

aleks
Reply to  davidbennettlaing
February 16, 2018 7:38 am

O’key, let’s think. UV-radiation Is a source of global warming. The ozone absorbs UV-radiation, so ozone depletion should lead to an increase in temperature. The largest ozone hole at the end of the last century was over Antarctica. However, in fact in Antarctica in these years there was cooling:
http://www.scienceagogo.com/news/20020015034521data_trunc_sys.shtml

davidbennettlaing
Reply to  aleks
February 16, 2018 12:50 pm

The largest warming trend in the world between 1976 and 2000 was near ice-free portions of the Antarctic Peninsula. The high albedo of most of the continent beneath the ozone hole reflected away most of the incoming radiation.