From the Massachusetts Institute of Technology
Plugging an ozone hole
MIT researchers find that the extremes in Antarctic ozone holes have not been matched in the Arctic
CAMBRIDGE, Mass– Since the discovery of the Antarctic ozone hole, scientists, policymakers, and the public have wondered whether we might someday see a similarly extreme depletion of ozone over the Arctic.
But a new MIT study finds some cause for optimism: Ozone levels in the Arctic haven’t yet sunk to the extreme lows seen in Antarctica, in part because international efforts to limit ozone-depleting chemicals have been successful.
“While there is certainly some depletion of Arctic ozone, the extremes of Antarctica so far are very different from what we find in the Arctic, even in the coldest years,” says Susan Solomon, the Ellen Swallow Richards Professor of Atmospheric Chemistry and Climate Science at MIT, and lead author of a paper published this week in the Proceedings of the National Academy of Sciences.
Frigid temperatures can spur ozone loss because they create prime conditions for the formation of polar stratospheric clouds. When sunlight hits these clouds, it sparks a reaction between chlorine from chlorofluorocarbons (CFCs), human-made chemicals once used for refrigerants, foam blowing, and other applications — ultimately destroying ozone.
“A success story of science and policy”
After the ozone-attacking properties of CFCs were discovered in the 1980s, countries across the world agreed to phase out their use as part of the 1987 Montreal Protocol treaty. While CFCs are no longer in use, those emitted years ago remain in the atmosphere. As a result, atmospheric concentrations have peaked and are now slowly declining, but it will be several decades before CFCs are totally eliminated from the environment — meaning there is still some risk of ozone depletion caused by CFCs.
“It’s really a success story of science and policy, where the right things were done just in time to avoid broader environmental damage,” says Solomon, who made some of the first measurements in Antarctica that pointed toward CFCs as the primary cause of the ozone hole.
To obtain their findings, the researchers used balloon and satellite data from the heart of the ozone layer over both polar regions. They found that Arctic ozone levels did drop significantly during an extended period of unusual cold in the spring of 2011. While this dip did depress ozone levels, the decrease was nowhere near as drastic as the nearly complete loss of ozone in the heart of the layer seen in many years in Antarctica.
The MIT team’s work also helps to show chemical reasons for the differences, demonstrating that ozone loss in Antarctica is closely associated with reduced levels of nitric acid in air that is colder than that in the Arctic.
“We’ll continue to have cold years with extreme Antarctic ozone holes for a long time to come,” Solomon says. “We can’t be sure that there will never be extreme Arctic ozone losses in an unusually cold future year, but so far, so good — and that’s good news.”
Everyone seems to forget that the southern ozone hole was completely unexpected when it was found.
The lasting effect of major volcanic eruptions on temperature of the stratosphere is likely due to the reduction in ozone (see linked paper under graph).
http://climategrog.wordpress.com/?attachment_id=902
The fact that the hole has not got any bigger may be just as much due to the lack of volcanism as the result of banning CFCs.
archonix says: Everyone seems to forget that the southern ozone hole was completely unexpected when it was found.
Very good point. There is no data to say that this hole has not always existed.
This is a classic case, like the gulf stream slow down. They start measuring something that’s never been measured before, and five years later find it has changed. They them stupidly assume that must always be constant (since they never measured it before, it must be constant , right?) , do a linear regression , project 100 years outside the period of the data and say “OMG, if this “new” change continues it will be catastrophic , we must act NOW”.
Ten years, later they find it’s changes back again and it’s just another natural variation in climate.
Soloman’s paper is just an attempt to suggest that “we save the world last time, you’d better listen to us now”.
“But a new MIT study finds some cause for optimism: Ozone levels in the Arctic haven’t yet sunk to the extreme lows seen in Antarctica”
Directly contradicted by the usual suspects in the MSM !http://www.dailymail.co.uk/sciencetech/article-2605038/Britons-face-increased-risk-sunburn-Easter-hole-ozone-layer-directly-UK.html
When will we be free of this BS?
The balance of ozone creation / destruction appears linked to variations in solar activity and in particular changes in the mix of wavelengths received from the sun.
The observed ozone reduction occurred when the sun was active and now with a less active sun there are signs of recovery.
I am still waiting for new data as regards ozone amounts above 45km since 2007. For the period 2004 to 2007 ozone appears to have increased above that level at a time of quiet sun which was contrary to expectations.
“how do we know whether or not the hole hasn’t always been there?”
Try reading this aloud several times over, until it sinks in:
Sunlight (UV radiation) + Oxygen (O2) = Ozone (O3)
—————————————————————————
Okay, when you think you’ve got it, try the corollary:
NO sunlight (UV radiation) + Oxygen (O2) = NO Ozone (O3)
—————————————————————————-
Alright, from around July 21 until September 21, there is little or no sunlight at the South Pole, due to the tilt in the earth’s axis. Hence there is little or no formation of Ozone O3. The only ozone in the region is that carried in by the jet stream air currents, as previously described.
Ozone depletion, erroneously referred to as the “ozone hole”, starts in July, and reaches its maximum at the end of the third week in September, which is when all the scary stories about “holes in the ozone layer” appear in the MSM. After that, increasing sunlight replenishes ozone concentrations and after about six wees things are back to normal.
So, for how long has there been an “ozone hole”?
For as long as the earth has been tilted on its axis, the atmosphere has contained oxygen, and the sun has produced UV radiation.
For how long will there be an “ozone hole”?
For as long as the earth remains tilted on its axis, the atmosphere continues to contain oxygen, and the sun produces UV radiation.
@ur momisugly memoryvault1 commented on Good news: no ‘ozone hole’ in the Arctic.
in response to Anthony Watts:
From the Massachusetts Institute of Technology Plugging an ozone hole MIT researchers find that the extremes in Antarctic ozone holes have not been matched in the Arctic CAMBRIDGE, Mass– Since the discovery of the Antarctic ozone hole, scientists, policymakers, and the public have wondered whether we might someday see a similarly extreme depletion of ozone […]
“how do we know whether or not the hole hasn’t always been there?”
Try reading this aloud several times over, until it sinks in:
Sunlight (UV radiation) + Oxygen (O2) = Ozone (O3)
—————————————————————————
Okay, when you think you’ve got it, try the corollary:
NO sunlight (UV radiation) + Oxygen (O2) = NO Ozone (O3)
—————————————————————————-
Alright, from around July 21 until September 21, there is little or no sunlight at the South Pole, due to the tilt in the earth’s axis. Hence there is little or no formation of Ozone O3. The only ozone in the region is that carried in by the jet stream air currents, as previously described.
_____________________________________________________________________
Hey, Mr Pot, from the Kettle:
I hear you talkin’, but you haven’t proven anything. I admit it’s plausible—and I wanted to thank you for the history lesson; I didn’t know that about the early Jet Stream theories and proof. Always good to learn something new—but you haven’t proven it. Plausible ain’t proof.
“Everyone seems to forget that the southern ozone hole was completely unexpected when it was found.”
Yeah, right. That’s why Professor Gordon Dobson spent years designing and refining the Dobson Spectrophotometer, and the Dobson Unit, to measure atmospheric ozone concentrations. Then, in 1957 – the International Geophysical Year, the British decided to form the British Antarctic Research Team and send it to Antarctica to study atmospheric conditions.
Because Professor Dobson had invented this cool piece of scientifical gear that didn’t serve any known useful purpose at the time, and because he happened to be sitting around twiddling his thumbs doing nothing much at the time, the British Research Team decided to include him in the team, and make his measurements of Antarctic ozone levels the central theme of their work.
And Lo! in a burst of Fortean logic, the “completely unexpected” southern ozone hole was “found”.
The ozone hole occurs naturally when the temperature of the ozone in the zone falls to a sufficiently low level.
http://www.cpc.ncep.noaa.gov/products/stratosphere/strat-trop/gif_files/time_pres_TEMP_MEAN_ALL_NH_2013.gif
climatereason says: April 16, 2014 at 12:48 am
“So the appearance of the hole in modern times due to man is complete speculation based on physics theory.”
So is the safety of the design of any modern bridge.
“Nick Stokes says:
April 16, 2014 at 2:43 am
climatereason says: April 16, 2014 at 12:48 am
“So the appearance of the hole in modern times due to man is complete speculation based on physics theory.”
So is the safety of the design of any modern bridge.”
We’ve been building bridges a lot longer than we “noticed a hole” over a magnetic pole of a very short lived, volatile, gas. But good one matey, made me chuckle!
The games been up for the ozone scam since at least last year…
Weather ‘behind ozone hole changes’
“Satellite images show that fluctuating air temperatures and winds change the amount of ozone gas that sits above Antarctica.
And scientists believe this is dictating the apparent size of the ozone hole changes year on year.”
Article available here…
http://www.bbc.co.uk/news/science-environment-25344563
Some aspects of the climate debate I have looked into
or feel more confident about discussing them. I have not
looked into the various claims discussed here so I simply make the following
observation: I see many claims that some effect on the climate
or atmospheric levels of aerosols or ozone, etc. are all due to
passing federal legislation. This always amuses me because I
had previously seen other explanations by different “warmists”.
In some people’s view, if you pass a law, it automatically works
and any later problems could never have anything to do with
previous laws. Apparently it is an almost never-ending succession
of wise decisions by intelligent legislators responding only to true
science and the sage advice of good citizens. This applies to any
law, not just those affecting the environment.
I have seen people claim (in quality journals) that the 1973 pollution
laws (in the US) had effects on world climate and now that the Montreal
protocol had all these wonderful effects. As always, I am skeptical.
Interesting that the 1973 laws in the US (only 4% of land mass remember)
had an effect on world climate. As a chemist I understand the reactions
that break down ozone although I have not looked at them in awhile. But
I also remember later articles in Science or Nature that explained new
effects not covered by the Montreal protocol and more importantly, I
remember articles discussing the fact that the ozone holes have
probably always been there to some extent. Which complicates the
simple narrative that some promote.
And how come there is no ozone hole in the Arctic when over 80% of the world CFCs have been produced and consumed in the Northern hemisphere?
And what is chemical basis of that assertion? Chemical reactions go faster as temperature rises. Where do these MIT researches store their perishable chemicals? In the frigde or in the oven? Cold is supposed to slow down chemical reactions, included the detradation ones, not to accelerate them, as the article suggest.
***
“It’s really a success story of science and policy, where the right things were done just in time to avoid broader environmental damage,” says Solomon
***
Prove it.
Just The Facts says:
April 15, 2014 at 7:33 pm
“Gary Pearse says: April 15, 2014 at 4:12 pm
I won’t go into it all again in detail, but expect there to be a CO2 hole, N2 hole, noble gases hole and methane hole coincident with the ozone hole (GP).
(JTF) …Not to say that magnetic and chemical are not necessarily factors, but what portion of the Ozone “Hole” can’t be explained by dynamical effects within polar vortices?”
JTF, your illustrated presentation is indeed convincing and I have no argument with the presence of such powerful dynamic factors as the vortex. And yes, it does make a bit of a crucible for reaction and even my theory requires some reaction to make ozone in the first place. However, there is no question that the gases I cite have the magnetic properties I cite, so, to me, the only question is the matter of magnitude of effect. Unfortunately, because of the CFC forgone conclusion, they don’t measure the atmospheric gases I suggest, but rather reaction products in the atmosphere.
Here is my challenge: a) if CO2, N2, CH4, Ne, Ar, Xe, O3 are all depleted at the height of the O3 hole AND O2 is more abundant than average atmosphere; b) if the depleted elements are more abundant relative to average atmosphere in the temperate zone to the equatorial zone AND O2 is somewhat depleted there, this would be support for a magnetic effect and its magnitude would be qualitatively measured by the degree of fractionation of these gases between these geographies. Fair enough? The person I’m approaching for an estimate of the effect from first principles is an engineering physicist I have worked with in the development of an idea of mine for an industrial application of magnetics (it has nothing to do with gases but I have this type of data). Perhaps the atmosphere is a little more interesting and complex than even we skeptics think it is – dynamical, chemical and physical properties of the atmosphere as a whole and of its constituents.
Eli Rabett says: April 15, 2014 at 9:18 pm
Stratospheric Polar Vortices – Waugh et al.[/caption]
urederra says: April 16, 2014 at 5:01 am
the principle difference between the Arctic and Antarctic wrt ozone depletion is that the south is a lot colder.
And how come there is no ozone hole in the Arctic when over 80% of the world CFCs have been produced and consumed in the Northern hemisphere?
“The vortex is most powerful in the hemisphere’s winter, when the temperature gradient is steepest, and diminishes or can disappear in the summer. The Antarctic polar vortex is more pronounced and persistent than the Arctic one; this is because the distribution of land masses at high latitudes in the northern hemisphere gives rise to Rossby waves which contribute to the breakdown of the vortex, whereas in the southern hemisphere the vortex remains less disturbed.”
http://en.wikipedia.org/wiki/Polar_vortex
“Towards the end of the southern winter season, planetary-scale wave events do begin to form and propagate upward into the stratosphere. These waves erode the vortex, decelerate the jet stream, warm the polar region, and increase ozone levels. While the northern polar vortex usually persists to March or April, the southern vortex persists an additional 1–2 months (November or December). In addition, temperatures remain quite cold (below 195 K) in the southern vortex to early October.”
http://ozonewatch.gsfc.nasa.gov/facts/vortex_NH.html
“Ozone depletion over Antarctica did occur without delay, but required several days longer to deplete to the 220 DU “ozone hole” threshold. Once this threshold had been reached the ozone hole size grew very rapidly. At the same time the areas at which temperatures were below 78C (the temperature to form Polar Stratospheric Clouds) also grew to above normal levels as shown in Figure 1c. The result was that the 2008 ozone hole grew to have the fifth largest single day size. Figure 1b shows that at this same time the SH polar vortex became larger than normal. The large size of the SH polar vortex persisted through October, November and December. In fact this year the polar vortex persisted beyond any previous year back to 1979. Consequently, the area of depleted ozone below 220 DU also persisted to the latest date.”
http://www.cpc.ncep.noaa.gov/products/stratosphere/winter_bulletins/sh_08/
“However, it is clear from the TOMS data that ozone transport and especially the timing of the vortex breakdown can have a large influence on the monthly mean total ozone, especially for October and November, when the vortex breakdown usually takes place. When the vortex breakdown occurs early (late) the October mean ozone is high (low).”
http://geotest.tamu.edu/userfiles/213/GL013i012p01193.pdf
The trend towards toward a later vortex breakdown, i.e. greater persistence;
[caption id="" align="alignnone" width="500"]
delays “the erosion of the vortex, deceleration of the jet stream, warming of the polar region, and increase in ozone levels”, thus the “trend over the 1980s and 1990s toward a later vortex breakdown” is the likely the primary cause of the Ozone “Hole” during October.
Gary Pearse says: April 16, 2014 at 6:33 am
Here is my challenge: a) if CO2, N2, CH4, Ne, Ar, Xe, O3 are all depleted at the height of the O3 hole AND O2 is more abundant than average atmosphere; b) if the depleted elements are more abundant relative to average atmosphere in the temperate zone to the equatorial zone AND O2 is somewhat depleted there, this would be support for a magnetic effect and its magnitude would be qualitatively measured by the degree of fractionation of these gases between these geographies. Fair enough?
What evidence do you have that “O2 is more abundant than average atmosphere” “at the height of the O3 hole” within the polar region, during the polar night, i.e. within the Polar Vortex?
This is one of my favorite threads! What a delightful and educational discussion about the actual science of a topic that is so poorly understood by so many ever since the Montreal Protocol. Many thanks to all who have contributed. This site is terrific.
That’s…just…wrong.
The ozone destroying properties of CFCs were never “discovered”. They were theorized based on computer models.
“wbrozek says:
April 15, 2014 at 3:36 pm
george e. conant says:
April 15, 2014 at 3:22 pm
CFC’s way to heavy to get above troposphere
Buoyancy does not apply to gases or liquids dissolved in gases. If it did, you would never see clouds above the ground since liquid water is much denser than air.”
For a gas distribution , check “scale height’
http://en.wikipedia.org/wiki/Scale_height
The formula is H = kT/Mg. for air, M is about 29. For Freon-11, the molar mass is
137.37 , so the scale height for freon-11 is about 29/137.37 the scale height of air.
Of course there’s no ozone hole in the arctic, because ozone levels are correlated to stratospheric temperatures, they only get depleted when it’s too cold. It just means that stratospheric temperatures in the arctic are not as low as in antarctic. It’s good that there is still some honnest research out there. I’ve always wondered about that CFC scam, because since CFCs are heavy gases, their molecular weight is such that they should be concentrated in the lower troposhpere, and couldn’t reach the altitude of stratosphere in the first place. Well, we’re off for another highlander 2 remake with CO2 anyway, since the theory mostly comes from the same scientists.
http://en.wikipedia.org/wiki/Scale_height
Interesting stuff there:
“For planetary atmospheres, scale height is the vertical distance over which the pressure of the atmosphere changes by a factor of e (decreasing upward). The scale height remains constant for a particular temperature”
From which it follows that if the temperature changes then the height of the atmosphere changes.
Then, since density also reduces, there is a cooling effect to offset the initial temperature change.
So, if GHGs absorb energy from the ground they will become warmer but they and the other molecules to which they conduct that warmth will rise higher to offset any potential effect on surface temperature.
That brings us to issues of the adiabatic lapse rate and the effective emission height.
Note that “Density is related to pressure by the ideal gas laws” which is what I have been saying here and elsewhere for some time.
Note too, the links to the scale heights for other Solar System bodies.
Where does radiative theory deal with the thermal effect of changes in density via variations in the scale height ?
Notably, the ozone “hole” is bigger in the hemisphere with less human population. Would that not mean that it has nothing to do with human activity?
Alan McIntire says:
April 15, 2014 at 3:28 pm
When there’s sunlight, ultra-violet rays create Ozone. Ozone is unstable, and quickly breaks down. Those long Arctic and Antarctic winters give the Ozone plenty of time to break down naturally, without being replenished by more sunlight created Ozone.
Unfortunately for your theory this isn’t what happens! During the winter the ozone concentration doesn’t decline, this occurs in the spring after the sun rises there.
http://www.esrl.noaa.gov/gmd/dv/spo_oz/1220plot.html