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.”
Banning Ban spray deodorant must have worked!
Alejandro Rodriguez says:
April 16, 2014 at 9:12 am
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?
_____________________________________________________________________________
Actually Ozone is one of the gasses in car exhaust, so it makes sense that there is more ozone where people live. And if you say that never makes it to the upper atmosphere I’m going to scream.
Ozone production over Antarctica is limited due to the fact that very little ultraviolet light reaches the atmosphere there (because UV has to pass through the atmosphere closer to the equator and is blocked by the ozone present there). Therefore, I believe that diffusion is required to maintain ozone levels above Antarctica. The problem is that a circular wind blows during the month of October and prevents diffusion resulting in ozone-destroying dust or chemicals (all natural) depleting the concentration of ozone. When the wind stops blowing, diffusion brings fresh ozone in from Australia and other areas.
“””””…..Tom K says:
April 16, 2014 at 10:13 am
Ozone production over Antarctica is limited due to the fact that very little ultraviolet light reaches the atmosphere there (because UV has to pass through the atmosphere closer to the equator and is blocked by the ozone present there). …..”””””
Well Tom, the hand is a good bit quicker tan the eye, only in trickery.
Let’s suppose the sun is five degrees above the Antarctic horizon. Tan (5) = 0.0875
We’ll call it 1/12. So if the ozone is 50 miles high, then that long air path starts 600 miles from the Antarctic; or where the ozone hole edge is.
So nyet on anything like tropical ozone levels.
But your point is valid, the low altitude of the sun, makes for a long air mass path to the Antarctic.
My Infra-red Hndbook, gives calculated earth spectra from outer space, and has plots for various sun angles out to 80 degrees (10 deg altitude). While the CO2 absorption bands don’t show a huge angle dependence, the 9.6 micron ozone hole in fact shows great angle sensitivity.
Very simple, the actual ozone layer is very thin, so an oblique path through it, can be much longer than in the case of a very thick layer going all the way to the surface, as in CO2.
So I agree with you, Antarctica does not get to make a lot of ozone anyway.
“””””…..elmer says:
April 16, 2014 at 9:57 am
Alejandro Rodriguez says:
April 16, 2014 at 9:12 am …..”””””
Start screaming then, because the lower atmosphere contains a whole lot of ozone poisons, like pool chlorine, and ozone itself can get broken down by just blue-green radiation from the sun.
So low level ozone gets destroyed long before it could make it up there.
“””””…..Phil. says:
April 16, 2014 at 9:23 am
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. …..”””””
But Phil, while that may be the case, it is also true that ozone is quite absorptive in the blue green region, and the big clip off the top of the air mass zero solar spectrum to give the surface (even air mass one) spectrum, is largely due to ozone.
So yes; in the spring when the sun rises, the sun angle is low, so the solar UV is strongly attenuated, but the blue green less so (but still attenuated) ;so I believe the sun at that time can destroy, what it cannot yet re-create, till it gets higher and the UV increases.
“””””…..archonix says:
April 16, 2014 at 12:55 am
Everyone seems to forget that the southern ozone hole was completely unexpected when it was found……”””””
Well No ! The ozone hole was only “unexpected” by those incapable of expecting one.
If you don’t expect something, you usually don’t go searching for it; well hell you don’t even know what it is that you are not expecting, so how would you know how and where to search.
The known variable color Temperature of surface solar spectrum radiation, that has a seasonal variation as well as erratic longer term variations, could only be the consequence of earth effects not solar effects (the seasonal part).
So early Air Force researchers, were already looking for some earth source of solar shortwave spectral changes with the seasons.
I don’t know if they thought ozone might be a cause or not, let alone a reason for seasonal changes.
Just The Facts says:
April 15, 2014 at 6:25 pm
Imagery of the Arctic and Antarctic Ozone Holes can be found in NOAA’s Ozone Mixing Archives;
http://www.cpc.ncep.noaa.gov/products/stratosphere/sbuv2to/archive/
JTF,
Thanks for the link!
I’ll have a look this evening.
Readers need to find and look closely at good modern plots, of both the extra terrestrial (air mass zero) and tropical surface (air mass one) solar spectra. They clearly explain how TSI at 1362-6 W/m^2 becomes around 1,000 W/m^2 at the surface, and the biggest chunk of that 25% or so chop, is a big clip of the peak of the curve (wavelength scale) in the 400-600 nm region.
Your curves should state that atmospheric O2 and O3 are a big cause of that loss. But also take note that the ordinary Raleigh scattering that gives us a blue sky, is clearly attenuating (by scatter) in the blue region around 450-70 nm, near the solar peak.
But Oxygen and Ozone both absorb significantly near the solar spectrum peak.
Ozone is quite unstable, which is why even radiation in the 500 -600 nm (blue to yellow) can break it down to oxygen.
So Ozone DOES NOT need chemicals to break it down; the sun can do it just fine.
But at least in the tropics, the solar EUV also breaks up O2 to give extremely reactive O, which immediately gloms on to another O2 to form ozone.
I once read a rather informative essay, by a then quite well known chemist essay writer, who explained how it is oxygen getting broken down by solar UV to make ozone, that is the real protector from high energy photons. Is it lost on some people, that the UV bands that ozone is credited with protecting us from (UV-A-B C-whatever) are the very destroyers of the ozone.
So the sun itself destroys the ozone, but in the tropics, with small sun angles (from zenith), the EUV can make it fast enough to keep some there.
Also look at “justthefacts” atmospheric graph that shows the principal ozone layer being around 20-25 km high.
Of note; at least to this observer, is that the ozone layer is quite considerably higher in altitude than those exotic chemistry clouds, that infrequent visitor Eli Rabbett asserts are what is doing a number on the ozone in the Antarctic, but don’t form in the arctic.
Well in sunny California, I perpetually have to wear my Foster Grants in the daytime, because my eyes are quite sensitive to the solar peak rays, even at air mass 1.5, which is about what I get here.
So I’m not a believer in Eli’s chemistry; well the chemistry might be correct (I don’t know), but it clearly isn’t in the right place to do any harm to the ozone layer. Well one man’s opinion, anyway.
By the way, I use false color plots all the time to reveal subtle changes in patterns.
So that great blue hole over Antarctica looks quite ominous; but it is a horrific exaggeration of reality.
george e. smith says:
April 16, 2014 at 12:50 pm
Readers need to find and look closely at good modern plots, of both the extra terrestrial (air mass zero) and tropical surface (air mass one) solar spectra. They clearly explain how TSI at 1362-6 W/m^2 becomes around 1,000 W/m^2 at the surface, and the biggest chunk of that 25% or so chop, is a big clip of the peak of the curve (wavelength scale) in the 400-600 nm region.
Your curves should state that atmospheric O2 and O3 are a big cause of that loss. But also take note that the ordinary Raleigh scattering that gives us a blue sky, is clearly attenuating (by scatter) in the blue region around 450-70 nm, near the solar peak.
But Oxygen and Ozone both absorb significantly near the solar spectrum peak.
Ozone is quite unstable, which is why even radiation in the 500 -600 nm (blue to yellow) can break it down to oxygen.
George, the data I’ve seen for Ozone photolysis says that UV below 325nm is required to break the bonds, see any ref on the Chapman mechanism.
Also look at “justthefacts” atmospheric graph that shows the principal ozone layer being around 20-25 km high.
Of note; at least to this observer, is that the ozone layer is quite considerably higher in altitude than those exotic chemistry clouds, that infrequent visitor Eli Rabbett asserts are what is doing a number on the ozone in the Antarctic, but don’t form in the arctic.
The PSCs form between 15 and 25 km which is exactly where the ozone is depleted:
http://www.esrl.noaa.gov/gmd/images/spo_ozone_web.jpg
This disproportionate madness has advanced to a point where ozone depleting substance use is questioned for laboratory testing of medicines. Similarly to cAGW, this is also based on unsubstantiated hypothesis. They are both rooted from either cold and calculated cruelty or stupidity of elephantine proportions. Either way, those speeding up the natural selection by poverty, starvation, hypothermia and/or illness of the weakest should be ashamed.
Alan McIntire says:
April 16, 2014 at 7:30 am
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.
Thank you for that. However I must admit I am not 100% sure about this, but I think we were talking about two different things here. A while back, I looked at radon concentrations in the air and they were very close high up as well as near the ground. I do not believe that what you say contradicts what I said. My interpretation of what you are saying is that if our atmosphere was 100% Freon, then it would have a certain very low height on Earth. But that does not mean that in our present atmosphere Freon cannot be very well mixed to great heights. At 0.04%, CO2 certainly does not decrease as fast as your number would indicate.
Just The Facts says:
April 16, 2014 at 6:52 am
Gary Pearse says: April 16, 2014 at 6:33 am
“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?”
None. I was hoping Nasa might have measured it. Perhaps a proper measure would be the combined O2 and O3 since the latter would have been created from O2. Now an additional fact: the colder the temperature, the more magnetic is oxygen. Here is an experiment on Youtube at Harvard showing the difference between N2 and O2
““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”
Interestingly, I just came across another paper by Susan Solomon, “The mystery of the Antarctic Ozone ‘Hole'”, from 1988:
http://onlinelibrary.wiley.com/doi/10.1029/RG026i001p00131/abstract
“Total ozone levels over Antarctica have declined by about 50% over the past decade, principally during the spring seasons. This unprecedented and unanticipated change in the total ozone column has precipitated a great deal of research into the dynamics and chemistry of the Antarctic, and their contributions to the observed behavior of ozone there. Observations of the total ozone column and its vertical profile over Antarctica are reviewed. Theoretical models to explain the mysterious change in ozone abundances are described, along with observations of Antarctic temperatures. Both chemical and dynamical processes occurring in Antarctic spring may be related to polar stratospheric clouds. The radiative and chemical properties of these clouds are summarized. Available observations of other chemical species besides ozone (e.g., nitrogen dioxide, chlorine monoxide) are also discussed. The current status of the evidence supporting various theories of the behavior of ozone in the Antarctic is summarized.”
It reads like propaganda versus sober science and reminds me of this recent paper from the University of East Anglia, “Mysterious new man-made gases pose threat to ozone layer”;
http://wattsupwiththat.com/2014/03/09/mysterious-new-man-made-gases-pose-threat-to-ozone-layer/
and this old article from, Time – Feb 17, 1992:
“What does it mean to redefine one’s relationship to the sky? What will it do to our children’s outlook on life we have to teach them to be afraid to look up?
–Senator Al Gore, Earth in the Balance
The world now knows that danger is shining through the sky. The evidence is overwhelming that the earth’s stratospheric ozone layer–our shield against the sun’s hazardous ultraviolet rays–is being eaten away by man-made chemicals far faster than any scientist had predicted. No longer is the threat just to our future; the threat is here and now. Ground zero is not just the South Pole anymore; ozone zone holes could soon open over heavily populated regions in the northern hemisphere as well as the southern. This unprecedented assault on the planet’s life-support system could have horrendous long-term effects on human health, animal life, the plants that support the food chain and just about every other strand that makes up the delicate web of nature. And it is too late to prevent the damage, which will worsen for years to come. The best the world can hope for is to stabilize ozone loss soon after the turn of the century.
If any doubters remain, their ranks dwindled last week. The National Aeronautics and Space Administration, along with scientists from several institutions, announced startling findings from atmospheric studies done by a modified spy-plane and an orbiting satellite. As the two craft crossed the northern skies last month, they discovered record-high concentrations of chlorine monoxide (CIO), a chemical by-product of the chlorofluoro-carbons (CFCs) known to be the chief agents of ozone destruction.
Although the results were preliminary, they were so disturbing that NASA went public a month earlier than planned, well before the investigation could be completed. Previous studies had already shown that ozone levels have declined 4% to 8% over the northern hemisphere in the past decade. But the latest data imply that the ozone layer over some regions, including the northernmost parts of the U.S., Canada, Europe and Russia, could be temporarily depleted in the late winter and early spring by as much as 40%. That would be almost as bad as the 50% ozone loss recorded over Antarctica. If a huge northern ozone hole does not in fact open up in 1992, it could easily do so a year or two later. Says Michael Kurylo, NASA’s manager of upper-atmosphere research: “Everybody should be alarmed about this. It’s far worse than we thought.” http://faculty.washington.edu/djaffe/GEI/w3a.pdf
Gary Pearse says: April 16, 2014 at 4:51 pm
None. I was hoping Nasa might have measured it. Perhaps a proper measure would be the combined O2 and O3 since the latter would have been created from O2.
I haven’t seen any measurements “at the height of the O3 hole”, however much higher up, i.e. “above the mesopause” there does appear to be “low, perhaps exceedingly low, [O]”:
“Abundances of atomic oxygen and ozone have been measured by various techniques over northern Scandinavia during the MAP/WINE campaign in the winter 1983–1984. On 10 February at Kiruna, Sweden, rocket experiments used resonance fluorescence and twin path absorption at 130 nm to measure [O]between 70 and 178 km. Rocket-borne measurements of nightglow at 557.7, 761.9 and 551.1 nm and at 1.27 μm have also been obtained and [O]values derived from the atmospheric band intensities. Ozone abundances between 50 and 90 km have been determined from rocket-borne measurements of the ν3 9.6 μm nightglow intensity from Andøya, Norway, and Kiruna. These have been compared with [O3] measured on the same day from the Solar Mesospheric Explorer satellite, using measurements of dayglow at 1.27 μm, and with results from other rocket launchings in MAP/WINE. The results show evidence of low, perhaps exceedingly low, [O] and below normal [O3] above the mesopause. Below 75 km at night [O3] exceeded earlier and subsequent observations in the campaign. The measurements were made during a minor stratospheric warming, characterised by an offset polar vortex centred near the measurement zone.”
http://www.sciencedirect.com/science/article/pii/0021916987900237
I will keep my eyes out for measurements of oxygen within the stratospheric polar vortex.
Now an additional fact: the colder the temperature, the more magnetic is oxygen. Here is an experiment on Youtube at Harvard showing the difference between N2 and O2.
That experiment really isn’t representative of atmospheric physics. Firstly, they are using liquid oxygen, “Gaseous oxygen is paramagnetic also but is moving too fast to be affected by the magnets.”
http://www.physlink.com/education/askexperts/ae493.cfm
Secondly, the magnet they use in the experiment is “a large magnet”, the “magnetron magnet is big and heavy, with conical pole pieces” and a “strong field”. Even then, “the poles are extended with washers to leave about a one centimeter gap”, in order to achieve the desired effect:
http://sciencedemonstrations.fas.harvard.edu/icb/icb.do?keyword=k16940&panel=icb.pagecontent217390%3Ar%241%3Fname%3Dindepth.html%2Cicb.pagecontent216756%3Ar%241%3Fname%3Dindepth.html&pageid=icb.page91943&pageContentId=icb.pagecontent217390&state=maximize
In comparison the “coil gap of a typical loudspeaker magnet” is “10 kG to 24 kG”, whereas “strength of Earth’s magnetic field at 50° latitude” is “580 mG”, i.e. more than 4 orders of magnitude less:
http://en.wikipedia.org/wiki/Orders_of_magnitude_%28magnetic_field%29
As such, the influence of Earth’s magnetic field on chemical constituents within the Polar Vortex are likely de minimis in comparison to the centrifugal force of the Polar Vortex, i.e.:
“Antarctic vortex: The combination of drastic temperature and corresponding pressure drop along with the rotation of the Earth on its axis produces a spinning/rotating volume of air. The rotational speed of the winds commonly reaches as high as 180 mph. The motion of these winds form an impenetrable barrier such that the trapped air inside is unmixed, as it is separated from the air outside, and remains quite cold (temperatures drop below 80 Celsius). Inside the whirling volume of freezing air, the cold temperatures facilitate the condensation of gases into particles that eventually for polar stratospheric clouds.”
http://books.google.com/books?id=LflaqbSX1xAC&pg=PA30&lpg=PA30&dq=polar+vortex+speed+rotation+stratosphere+mph&source=bl&ots=2vU3tmZCAC&sig=b1tM3_FwjKlrp-0vIKwYxRtLrwU&hl=en&sa=X&ei=yYcuU7e4KcTI0AGZoYDoCg&ved=0CHYQ6AEwCQ#v=onepage&q=polar%20vortex%20speed%20rotation%20stratosphere%20mph&f=false
“The peak August wind value is 84 m/s (190 mph) at 5 hPa (about 37 km). This peak tends to occur at latitudes around 60°S.”
“As the amount of sunlight decreases and temperatures drop in southern polar region, the night jet winds increase. So too does the degree of isolation. At higher altitudes, the polar vortex begins to develop in the March-April (early fall) period and is fully developed by May, corresponding to the onset of the period of complete polar night darkness. At lower altitudes, the vortex develops more slowly, not becoming fully developed until the June-July (early to midwinter) period. This vortex development is also illustrated in Figure 11.15 in a latitude-versus-time plot showing the evolution of the winds on the 50 hPa (approximately 20 km) surface. Both figures are based on data from 1979-1995.”
“The polar night jet reaches its maximum wind speed in the August-September (mid- to late winter) period. It breaks up in the November-December (mid- to late spring) period. Figure 11.13 shows us that the polar night jet is almost always centered at 60°S. In contrast to this southern polar night jet, the northern hemisphere polar jet is weaker in mid-winter, and has decreased in strength by late winter (February-March). The Antarctic polar night jet breaks up in mid-to-late spring (October-December), nearly 2 months later in the southern seasonal cycle than the breakup of the Arctic polar night jet in the northern seasonal cycle. This is due to the faster winds of the southern polar jet and the colder temperatures and greater degree of isolation of air inside the Antarctic polar vortex than their northern counterparts.”
http://www.ccpo.odu.edu/~lizsmith/SEES/ozone/class/Chap_11/11_3.htm
“Patrick says:
April 16, 2014 at 2:57 am
“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!”
Patrick
What Nick said is beyond stupid, We know through testing not theory the strength of steel concrete and through math the forces place on a bridge can be calculated, modern are built on long time tested know quantities, there is no speculation. When a bridge fails we generally can determine the cause when a certain bridge failed
In Minnesota a few year ago all speculation an guess ended when it was determined that the gusset plates were made of 1/2 inch steel instead of 3/4 as originally specified, we also know the bridge stood there for over fifty years before the flaw was revealed when the state and the construction company overloaded its “build”, not it design although one could speculate maybe it not wise to stress a fifty year old structure like that but the design was not the problem.
Comparing the ozone hole and why it occurs to bridge design is infantile and show a small mind. How a bridge is built and test is understood science. where what and how the the ozone hole is created is basically speculation. We do not have good measurement as to what the gases are and how they interact up there. since there are no chart quantifying the lack of sunlight temperature and the gas mix they yes we have some measurements but it like having a blind man sampling water he may be able to tell if it fresh or salty but he would have no idea if he was on the pacific ot the atlantic or the great lakes or the Mississippi, on top of the the bulk of chlorine and fluorine in the atmosphere comes from the oceans, these facts of course need to be hidden since they do not help the anti CFC crowd.
All I know for sure is I am pissed every new air conditioner i buy. I am told how more efficient the new one is, as oppose to the old one, yet to run it takes more energy to run it and end up costing me more money. Funny their efficiency number on replacing CFC don’t pencil out in the real world also.
“Werner Brozek says:
April 16, 2014 at 4:14 pm
… A while back, I looked at radon concentrations in the air and they were very close high up as well as near the ground. …”
The higher the lapse rate, the higher the greenhouse effect. If different gases follow a “scale height’ distribution, there’s little convection, a large greenhouse effect.
If gases are evenly distribued over a larger range than that “scale height” factor, that’s an indication that there’s a very strong negative feedback due to convection, when due to heating, large parcels of air are lifted higher in the atmosphere.
Obviously there are a lot of misconceptions here. Let Eli start with this one
“But Oxygen and Ozone both absorb significantly near the solar spectrum peak.”
The peak of the solar spectrum is in the green, not the UV (btw evolution would say that that is where people would see best, and you know what that is where people see best), right about where the Stefan Boltzmann law says that a light source like the Sun would peak.
To continue, if you look at the absorption spectrum of ozone, it is a continuum between ~300 – 200 nm, very much like a bell curve. Thus ozone absorbs all of the solar radiation between 300 and 200 nm. What happens at shorter wavelengths, well, oxygen, O2 starts absorbing strongly, so higher up, above the ozone layer, the oxygen absorbs all the sun light in the < 200 nm region.
Further, if you look at the solar spectrum, you see that the intensity falls off strongly below say 350 nm (There is an exception to this Lyman alpha 124 nm radiation from hydrogen, but that too gets absorbed very high in the atmosphere).
Alan McIntire says:
April 17, 2014 at 9:18 am
Thank you! This may be a good point to bring up on the next article on man-made CO2 where Ferdinand Engelbeen gets involved.
“””””…..Eli Rabett says:
April 17, 2014 at 10:52 am
Obviously there are a lot of misconceptions here. Let Eli start with this one
“But Oxygen and Ozone both absorb significantly near the solar spectrum peak.”
The peak of the solar spectrum is in the green, not the UV (btw evolution would say that that is where people would see best, and you know what that is where people see best), right about where the Stefan Boltzmann law says that a light source like the Sun would peak……”””””
Given that Phil elaborated on Eli’s statement, that some fancy chemicals form clouds right where ozone depletion occurs, and rereading the ozone altitude chart that was supplied here by justthe facts, which seems to show the peak of ozone concentration lies somewhat above Eli’s clouds, I will retract my assertion, that the ozone layer is well above Eli’s clouds; only some of it is above those clouds.
However, no misconception here Eli; the solar spectrum, as you well should know, does not follow the Planck Black Body radiation law, and especially near the peak wavelength which is actually shorter, than the Planck Law predicts; but has a significant anomalous higher peak, shorter wavelength than the Planck law predicts.
I’m not sure exactly how the Stefan Boltzmann law got involved in this.
But MY standard reference text on such matters is “The Infra-Red Handbook”, which I’m sure is well known to both Eli, and Phil. (The handbook, not that it is my standard reference.)
Anyhow, I am not going to bother to give the details of that text, since I have done so, in gory detail at least 20 times, here on WUWT.
And the solar spectrum curves in that text show overlapping air mass zero and air mass one spectral curves, including significant absorption near the sun spectral peak, which the text book claims is due to O2 and O3.
If it was possible to cut and paste to this site, I could post those very curves, and also the standard solar spectral table values for air mass zero, and air mass 1.5 (maybe it’s 2.0); and I can also reference the original peer reviewed papers that are the source of that data.
So if my data is good enough for the United States Navy, who commissioned this text, and also for the United States Air Force, who did much of the studies, then it is good enough for me.
But If Eli, has more up to date peer reviewed data, that he would like to share with us, I’m sure Anthony would allow him to post it here.
I must admit, that I don’t quite understand, why it is that Ozone, would exhibit a “Continuum spectrum”, since such spectra are usually seen with plasmas, that involve transitions from an ionized state, or else due to thermal energy collisions between molecules, that are a function of Temperature and density.
Given that climatologist assert that the main atmospheric gases do not emit thermal continuum (Planckian) radiation spectra; an assertion I reject, it is difficult to see how ozone, in earth’s atmosphere would have detectable spectra of that nature, in addition to its molecular spectrum due to the molecular structure and energy levels.
But I’m willing to learn, and would enjoy knowing more about ozone continuum spectra.
I must admit, that I have never ever read, any definitive statement of the wavelength(s) necessary for dissociation of O2, nor the precise wavelengths that break down O3 to O2 + O.
It is frustrating to have no access to basic information that any and every worker in the weather/climate field ought to have at their fingertips at all times.
I know I keep ALL of the pertinent information in my fields in my head at all times; so I don’t have to giggle or Wikipedia anything to do my job.
But my apologies to Eli Rabbett, for doubting his assertion of weird clouds at ozone levels. But if we can have ice clouds, at noctilucent altitudes, why not other clouds at ozone altitudes.
Do we have any photographs of such clouds, or are they just too visible spectrum transparent to show up in photos ??
I must read up on ozone continuum spectra in the UV.
For a Black Body radiation spectrum, the Planck spectral radiant emittance versus wavelength spectrum, contains almost exactly 25% of the total energy at wavelengths below the peak wavelength. I have never actually performed that integration myself, to find out if that fraction is exact, but every reference have ever seen says it is 25%, and all the plotted curves show it as that.
They also show that just 1% of the total radiant energy lies at wavelengths shorter than one half of the peak wavelength, which would be 250 nm for a BB spectrum peaking at 500 nm. And 99% of the total radiant energy lies below 8.0 times the spectral peak wavelength, which would be at 4.0 microns, so less than 1% of the radiant energy from such a source (and the sun) lies beyond 4.0 microns, so the CO2 asymmetrical stretch mode, has little effect on incoming solar energy, and also the 10.1 micron peaked, near BB emission, from a 288 K mean earth surface, would also have less than 1% of its radiant energy below 5.05 microns, which also leaves that CO2 band out in the cold.
Now in the hottest tropical deserts that do most of the earth’s radiant cooling, the asymmetrical stretch CO2 band would start to have some absorption of outgoing energy.
Just The Facts says:
April 16, 2014 at 8:04 pm
Gary Pearse says: April 16, 2014 at 4:51 pm
GP: “Now an additional fact: the colder the temperature, the more magnetic is oxygen. Here is an experiment on Youtube at Harvard showing the difference between N2 and O2.”
JTF, I realize the experiment is not one that reflects the physics of the atmosphere – it was just a neat demonstration that the unique magnetic susceptibility of oxygen is real- but you don’t have to go to as far as liquid oxygen to see a substantial increase in the magnetic susceptibility of oxygen (and other substances) with declining temperature. I haven’t found a good link to show this and I’m not a capable electronic manipulator of illustrations for this medium, but within the temperatures that can be experienced above the poles, the mag suscept. can double and triple. Yes, the force isn’t strong, but when the entire medium acted upon is the very fluid atmosphere and there are two mutually supportive effects added together: pushing away all the gases except oxygen would by itself suck oxygen into the voided area by the pressure difference. When you have the oxygen actually attracted into this region the effect is reinforced. Your vortex mechanism may totally overwhelm mine when it is active. I still would like to see as good a job measuring distribution of the standard gases in the atmosphere. Here is one for CO2 (just located), of interest, particularly, the South Polar region – the pattern even looks like lines of magnetic force although this might be an artifact of data points.
http://commons.wikimedia.org/wiki/File:Nasa_AIRS_CO2_July03.jpg
Grammar question:
” 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 reaction between chlorine and what? What is the sound of one hand clapping?
A post of mine did not post; that happens some times. It was a response to Eli’s response to my response to his response.
I’m not going to reproduce it all; I’m tired of stupid machines that fail to do what they are told to do.
But for the record, In view of Phil’s post, I would retract my comment about Elis weird chemistry clouds. The rest of my earlier post I stand by, based on my standard References on solar radiation physics; mainly The Infra-red Handbook, which I’m sure Eli and Phil are well aware of; and probably have their own copies of.
My apologies to Eli, re the cloud chemistry .(which is NOT in my references.)
Do we have any photographs of such clouds, or are they just too visible spectrum transparent to show up in photos ??
Anything to oblige George.
http://upload.wikimedia.org/wikipedia/commons/7/77/Polar_stratospheric_cloud_type_2.jpg
I must read up on ozone continuum spectra in the UV.
As I recall it’s because the transition is to energy levels in the excited state of ozone, a pre-dissociated state which has no energy minimum. In those states there are no discrete vibrational energy levels and therefore you get a continuum spectrum.
Excited state B in this diagram: http://www.pci.tu-bs.de/aggericke/PC4e/Kap_III/Praed_1.gif
See:
Hollas, J. Michael (2003). Modern spectroscopy (4th ed.). Wiley. p. 253. ISBN 978-0-470-84416-8