Talk:Ozone layer

Please somebody explain this to me.

The article doesn't give the "thickness" (that is, distance from bottom to top) of the ozone layer. This link from Caltech gives information that I would like to see explained in the article. http://coolcosmos.ipac.caltech.edu/cosmic_kids/AskKids/earthozone.shtml --70.131.51.64 09:09, 29 March 2007 (UTC)

Its not a very good answer. Thats the thickness it would have if it were just a layer of pure ozone (at SLP?). The thickness of the atmos layer that ozone occurs in in is ?30 km? William M. Connolley 09:21, 29 March 2007 (UTC)

The article currently just says that thickness varies; we could use something more specific. -- Beland (talk) 12:25, 1 February 2025 (UTC)

State of regulation on bromofluorocarbons

Bromofluorocarbons, which besides CFC's also have high ozone depletion value, have not been described, in regard to regulation (by industrial and developing countries). As besides CFC's this too has extremely high ozone depletion value it should be described. Besides this, there should be a list or reference in what products CFC's and bromofluorocarbons are present (as still sold in developing countries). KVDP 13:06, 30 Mar 2004 (UTC)

Bromofluorocarbon mentions these were banned by the Montreal Protocol. This article was linking to the wrong placed; I updated that to help clarify. There is more info on Ozone depletion. -- Beland (talk) 12:42, 1 February 2025 (UTC)

why is no one paying attention to the hole in the ozone layer anymore?

why is it not as much of an issue as global warming? AbsoluteZero255 18:48, 25 October 2007 (UTC)

The usual answer to "why" is "money". But the article needs sources which state why before the article can state why. (SEWilco 19:10, 25 October 2007 (UTC))

Because Gore wouldn't get a Nobel for that —Preceding unsigned comment added by 217.67.17.234 (talk) 15:17, 12 December 2007 (UTC) this means the ozone layer is tres inportant —Preceding unsigned comment added by 75.155.110.64 (talk) 18:21, 19 May 2008 (UTC) in our earth ozon layer is more edfdfected to people —Preceding unsigned comment added by 122.168.52.217 (talk) 17:08, 10 May 2010 (UTC)

Regulatory agencies do pay attention to ozone-depleting chemicals, preventing new ones from being used and getting rid of the last of the existing ones. It's probably not in the news as much because given the major sources of depletion have been banned, we're now just mostly waiting for them to be destroyed by natural processes and the problem to fix itself. -- Beland (talk) 12:25, 1 February 2025 (UTC)

Technology for replenishment

I am not very educated and some articles probably have already answered my question. Do we have the technology yet to replenish the ozone layer? If so, are we doing it or the price is too expensive to do so. —Preceding unsigned comment added by 59.37.8.105 (talk) 05:49, 27 September 2008 (UTC)

Theoretically, we could have planes or balloons fly around with ozone generators, but it would be massively expensive and difficult to manufacture at the needed scale compared to the relatively small benefit, and could create much bigger environmental problems with CO2 emissions or trash. Increasing the ozone concentration might mean that ozone-destroying chemicals just destroy ozone faster. So no, we're not doing that. We're just waiting for ozone-destroying chemicals we've already released to be destroyed. -- Beland (talk) 12:25, 1 February 2025 (UTC)

ozone layer in stratosphere

I was wondering, why is the ozone layer up in the stratosphere while ozone is heavier than normal air, I'd say the normal air should "float" on the ozone layer. of course, that wouldn't be healthy, but that's not an answer. — Preceding unsigned comment added by 84.87.38.168 (talk • contribs) 13:19, 12 January 2009 (UTC)

The ozone layer is in the homosphere, where wind-driven mixing is more important than gas weight, in contrast to the heterosphere (above about 90 km). -- Beland (talk) 12:32, 1 February 2025 (UTC)

I added a note to the article about this, since I think it's a question a lot of people are having. -- Beland (talk) 12:34, 1 February 2025 (UTC)

Question

I am puzzled about CFCs and HFCs causing ozone depletion and hope someone will response to my points. According to wikipedia, those chemicals' molecular weights are heavier than air, so how can they rise into the ozone layer and deplete it? As a heavy equipment mechanic who performs air conditioning work, I have found and have read that when using a "freon" leak detector, one must always place the meter underneath the suspected leak point to measure any "freon" escaping, and that placing the detector above the point will not trigger the meter, because the CFCs and HFCs are heavier than air. OK, if that is so, and the ozone layer allows only a small amount of UV light to strike earth's surface, I can understand that small amount of UV will break down those chemicals at ground level causing chlorine to be released. Now, according to wikipedia, the atomic weight of chlorine is heavier than air. So how can this chlorine rise eight miles into our atmosphere to deplete the ozone layer? An educated reply would be greatly appreciated.Chadjessup (talk) 18:41, 4 September 2010 (UTC)

those chemicals' molecular weights are heavier than air, so how can they rise into the ozone layer and deplete it - err, pause to think for just a moment. Are you also puzzled by the fact that the major constituents of the atmosphere - O2 and N2 - have different weights but don't separate out under gravity? If not... why not? Indeed, why aren't you puzzled that the minor consitiuents - which includes heavy noble gases - don't separate out. Pause to think about this for just a little while before reading Ozone depletion#Misconceptions about ozone depletion. William M. Connolley (talk) 19:16, 4 September 2010 (UTC)

Just because a gas molecule is heavier in atomic weight than ambient air doesn't mean that it cannot disperse due to diffusion, wind and natural air movement. It can't separate out because the effect that gravity has on gas molecules is negligible. Gas particles naturally diffuse through the air just like other fluids (gases and liquids are fluids). - M0rphzone (talk) 07:05, 27 April 2012 (UTC)

The answer is: the wind mixes things up and CFCs and HFCs end up at the same altitude as the ozone layer. You can certainly have a release of heavier-than-air gas sink in a wind-free indoor room, but if you turn on a fan or as people walk around the room and stir things up, the CFCs and HFCs will mix with the room air and soon will be filling the whole volume equally. There's lots of wind outside to mix things up. The homosphere, where atmospheric gases are well-mixed, goes up to about 90 km, well above the ozone layer. It's only in the heterosphere that atmospheric gases start to get sorted out by weight. -- Beland (talk) 12:01, 1 February 2025 (UTC)

HFCs are substitutes for CFCs and HCFCs; they do not cause ozone depletion. However they do cause global warming. HeyRobbie (talk)

Picture

you should add a nice picture like that:

Sources of Greenhouse gases and their reaction with the ozone-layer; NOx, SOx can arise from combustion processes

if you find errors, please contact me, I will improve it.--Smiles :( :\ :o :() (talk) 13:04, 8 April 2015 (UTC)

This has a lot of off-topic content; this pic is probably better used on a greenhouse gas article. (Currently not used by any.) -- Beland (talk) 12:44, 1 February 2025 (UTC)

Magic!

Chlorofluorocarbon molecules are 4-8 times heavier than air but we are told they rise into the upper atmosphere. How? Does helium ever sink towards the Earth?

The miniscule amount of Freon in the upper atmosphere is due to vulcanoes and escapes from aircraft.

I once wrote an article for a newspaper confessing that I had personally destroyed the entire Ozone Layer over Australia because I used a small aerosol can of Freon, as an electronics technician. The truth is that the Freon immediately fell downwards where soil bacteria digested it within a few weeks. — Preceding unsigned comment added by 1.144.111.240 (talk) 20:55, 6 January 2018 (UTC)

Actually, this question has been thoroughly and exhaustively answered. One only needs to conduct a quick google search to find the answers. For ease of access, here is the question answered in the World Meteorological Organization 'Scientific Assessment of Ozone Depletion: 1994', "Although the CFC molecules are indeed several times heavier than air, thousands of measurements have been made from balloons, aircraft and satellites demonstrating that the CFCs are actually present in the stratosphere. The atmosphere is not stagnant. Winds mix the atmosphere to altitudes far above the top of the stratosphere much faster than molecules can settle according to their weight. Gases such as CFCs that are insoluble in water and relatively unreactive in the lower atmosphere (below about 10 kilometers) are quickly mixed and therefore reach the stratosphere regardless of their weight.

Much can be learned about the atmospheric fate of compounds from the measured changes in concentration versus altitude. For example, the two gases carbon tetrafluoride (CF4, produced mainly as a by-product of the manufacture of aluminum) and CFC-11 (CCl3F, used in a variety of human activities) are both much heavier than air. Carbon tetrafluoride is completely unreactive in the lower 99.9 percent of the atmosphere, and measurements show it to be nearly uniformly distributed throughout the atmosphere as shown in the figure. There have also been measurements over the past two decades of several other completely unreactive gases, one lighter than air (neon) and some heavier than air (argon, krypton), which show that they also mix upward uniformly through the stratosphere regardless of their weight, just as observed with carbon tetrafluoride. CFC-11 is unreactive in the lower atmosphere (below about 15 kilometers) and is similarly uniformly mixed there, as shown. The abundance of CFC-11 decreases as the gas reaches higher altitudes, where it is broken down by high energy solar ultraviolet radiation. Chlorine released from this breakdown of CFC-11 and other CFCs remains in the stratosphere for several years, where it destroys many thousands of molecules of ozone."

The more you know... — Preceding unsigned comment added by Microscone (talk • contribs) 15:09, 22 January 2018 (UTC)

The idea that freon released from human activities goes into the ground and is destroyed is clearly wrong; not sure where that claim is coming from.

With regard to atmospheric mixing, we have great articles on the topic: the homosphere is the area where gases are well-mixed, and it goes up to about 90 km, well above the ozone layer. It's only in the heterosphere, above that, where gases start to sort out by weight. -- Beland (talk) 11:53, 1 February 2025 (UTC)

Wiki Education assignment: Introduction to Policy Analysis

This article was the subject of a Wiki Education Foundation-supported course assignment, between 28 March 2022 and 30 May 2022. Further details are available on the course page. Student editor(s): Sgamon (article contribs).

Update sources for Ozone introduction?

Hello, I'm pretty new to Wiki editing so I was perusing the sources when I saw the first source cited led me to a pretty old page on the Way Back Machine This is the source: https://web.archive.org/web/20171121051325/http://www.ozonelayer.noaa.gov/science/basics.htm since the ozone layer is part of the larger issue of CO2 output and atmospheric sciences, would it be wise to perhaps update the introductory citation to a newer and more frequently updated source? I found this source from the Environmental Protection Agency: https://www.epa.gov/ozone-pollution-and-your-patients-health/what-ozone which was last updated on June 16, 2021. Please tell me what you think and I can begin to edit the introductory paragraph. Thank you, --Sgamon (talk) 21:22, 24 April 2022 (UTC)

A few more critiques:

- "Venus also has a thin ozone layer at an altitude of 100 kilometers above the planet's surface." This sentence threw me off in the first paragraph, if anything, this sentence should be a part of a separate section talking about fellow planets with ozone layers and similarities amongst them.

- Information in Distribution in the Stratosphere section is biased towards Americans, reading "Research has found that the ozone levels in the United States are highest in the spring months of April and May and lowest in October. While the total amount of ozone increases moving from the tropics to higher latitudes, the concentrations are greater in high northern latitudes than in high southern latitudes, with spring ozone columns in high northern latitudes occasionally exceeding 600 DU and averaging 450 DU whereas 400 DU constituted a usual maximum in the Antarctic before anthropogenic ozone depletion." In order to maintain neutrality in the article and also to deliver best information, this section discussing the Distribution in the Stratosphere should take into account various countries and their ozone distribution.

finally,

- there are a few sources that do work but are however very very old, dating back over 20 years. Just because the Ozone layer was discovered long ago does not mean sources supporting the Wiki page need to be from then as well! It would be preferable to have updated and less hegemonies of info from solely American publications. Sgamon (talk) 07:25, 13 June 2022 (UTC)