Talk:Ozone depletion

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Talk:Ozone depletion/archive 1 (lots of disputes about POV)

Merge proposal

There's considerable overlap between ozone depletion and ozone hole, and somebody already deleted ozone depletion theory. So I think a merge is needed.

Let's try to cover the following ideas:

ozone's protective role - keeps too much UV from reaching the surface
destruction of ozone - by CFC (mostly) but also sunlight, et al.
connection of ozone depletion to increased UV at surface and harmful consequences of it

We may or may not choose to keep ozone hole as a separate article, but anything about the three points above should go primarily in another article.

I think we need at least articles, something like:

ozone depletion -- research on theory and actual observations of how stratospheric ozone has been going down each year -- no controversy, no politics: just the facts (heavy on peer-reviewed articls)
ozone depletion theory -- argument or "theory" relating CFC to ozone loss to UV increase to cancer increase + extent to which this theory has been (a) accepted and/or (b) actually proven (good place for Singer's objections) -- good place to mention Montreal Protocol

Care to have a go, William? --Uncle Ed 15:47, 16 Aug 2004 (UTC)

Sorry Kids already done! :o) Though much work needs to be done cleaning things up and organizing them. I merely moved the "fred singer sections" from both articles together at the bottom of the new merged page. I feel that things still seem to wander randomly in this article....I will let you and William hash the rest of this out. I must say I remain entirely unconvinced that yet another ozone depletion theory page should exist. Any information on the theory of ozone depletion belongs right here, if this necessitates an "non-mainstream theories" section or some such then that can go at the end of this article as well. We're merging these pages for a reason! Consolidation of information about the ozone layer and issues surrounding its reduction/destruction etc. --Deglr6328 02:38, 17 Aug 2004 (UTC)

Light relief

(William M. Connolley 10:25, 16 Sep 2004 (UTC)) And if all this is too serious, try:

http://community.oceana.org/story/2004/7/1/185446/7154

whats up?

Cleanup

I've just restored the cleanup tag to the page (which I deleted inadvertently this morning!). I agree with W.C. that I may have taken out a bit too much, but the page was in the cleanup list because it has "lots of redundant text / restatement" (see Cleanup list, September 2004). Do we have to have the Montreal Protocol mentioned three times, the biological effects of UV in several paragraphs, and the statement that "chlorine breaks up ozone catalytically" every four or five sentences? I believe the page can be reduced to half its size without loss of content. BTW there's already an ozone-oxygen cycle page. A shorter explanation and maybe a graphical diagram could be more useful. --Pablo D. Flores 21:40, 7 Jan 2005 (UTC)

(William M. Connolley 23:14, 7 Jan 2005 (UTC)) Hmmm... I'm not really sure the cleanup tag is needed, its more of a relic of the merge of ozone hole and ozone depletion I think. Lots of repetition has already been removed.

There *is* an ozone-oxygen cycle page but that page itself is marked for cleanup and is very sparse. You could make a case for moving text from the ozone cycle overview section over to there, but is there any point?

There is probably room for further improvement, though I don't find the repetition as jarring as you do, and I don't believe the page could be half the size.

OK, maybe that was an exaggeration. But I do think that the ozone-oxygen cycle should be moved (and then the main article could have, as it says, just an overview).

The text still has a lot of repetition (I can't imagine what it was before!) and the table of contents should be clearer. Also, I'm not sure if the POV disputes above were solved to everyone's satisfaction.

I don't want to step on your toes, but let me try this weekend or next week, and then you tell me what you think. --Pablo D. Flores 14:28, 8 Jan 2005 (UTC)

(William M. Connolley 15:09, 9 Jan 2005 (UTC)) OK. The POV disputes were mostly resolved I think. On a practical level, Ed Poor doesn't edit the climate pages so much anyway. I've archived the old stuff, so newcomers don't feel intimidated by its weight.

Is Ozone Depletion Real?

Latest comment: 19 years ago2 comments2 people in discussion

Do not turn away! This is not a rediculous theory.

The science of ozone (as understood by me):

Ozone is created on a regular, consistent basis. UV light hitting oxygen (O²) in the upper atmosphere causes it to become unstable, forming ozone (O³). However, ozone only exists in its unstable state for anywhere between .5 - 10 seconds before breaking down to form the more stable 0²! Then the whole process repeats over again.

Also, I have learned that the reason that ozone is thin at the poles is because less sunlight reaches that part of the earth. (Seen the science of it, definately plausible.)

I'm not sure about ozone quantity fluctuations, though.

Thoughts?

(William M. Connolley 19:16, 5 Mar 2005 (UTC)) Yes, ozone depletion is real. No, ozone does not break down in .5-10 seconds. Try the ozone FAQ (linked from the bottom of the page), in particular http://www.faqs.org/faqs/ozone-depletion/intro/ section 2.4. If you were correct about the lifetimes, there would be *no* ozone in the polar winter.

This could very well be true. He is saying that O3 is turned into O2. The O2 is then turned into O3. This is not ridiculous at all. — Preceding unsigned comment added by Gharkib (talk • contribs) 04:42, 19 February 2006 (UTC)Reply

The problem with the comment is not that it says there is a cycling between O2 and O3 but the timescale this requires. This whole idea is a red herrig. The science of this is very well understood and entirely consistent with the observed ozone depletion.--NHSavage 08:45, 19 February 2006 (UTC)Reply

Rm graph: why

(William M. Connolley 22:10, 17 Mar 2005 (UTC)) I removed thumb|Ozone CFC decline because it doesn't look right. The caption "Ozone CFC decline" is odd. Its not quite clear what its a graph of... is it measured CFC levels (unlikely, since it appears to be inconsistent with Image:Major greenhouse gas trends.png) or is it measured stratospheric chlorine levels or what?

Having said that, I'll thank SEW for his good work in adding various graphs to these articles.

More recent graphs inserted. Image page has details. CFC gases are not "major greenhouse gases" so there are more gases involved than in other image...and bromine. (SEWilco 06:46, 18 Mar 2005 (UTC))

Hole size?

Latest comment: 19 years ago1 comment1 person in discussion

"As the ozone hole over Antarctica has in some instances grown so large as to reach southern parts of Australia and New Zealand, environmentalists have been concerned that the increase in surface UV could be significant."

Is the above actually referring to low-ozone areas due to the hole breaking up? The "Largest Hole" image on the article doesn't seem to show much variation as far north as Australia. (SEWilco 03:18, 6 Apr 2005 (UTC))

The ozone hole for the 2005 season, peaked at 28,000,000 square miles, as measured by the NASA TOMS Satalite. You can view the past ozone pictures at the NASA TOMS satalite page.

[[1]]

The peak data is at [[2]]

The concern is also extended to doctors now that higher rates of UV-A and UV-B from the effected parts of South America, has been shown to cause higher rates of skin cancer.

Artoftransformation 11:53, 6 November 2005 (UTC)Reply

Interest in ozone hole

This remark reads rather oddly: "The sudden and, at that time explained, disappearance of over 50% of the ozone layer in a localized area of Antarctica created quite a stir". But what does "at that time" mean? I can quite believe the suddenness was fully expected and explained by the time there was a fuss. But was it? Or was the suddenness explained at the time the hole was first detected? Going from the rest of the article, would it be true to say that the overall effect was explained (or understood) but the suddenness was unexpected? In any case it would be helpful to put in a word about why an explained event caused a stir. Thincat 15:20, 11 Apr 2005 (UTC)

(William M. Connolley 15:35, 11 Apr 2005 (UTC)) As I understand it, the original Farman et al paper included not just the measurements showing ozone depletion but also the explanation: solid-phase reactions. The sentence is a bit odd because someone originally wrote "The sudden and, at that time unexplained, disappearance..." which makes sense as a sentence but is factually wrong; I simply inverted the original sense. It could perhaps be more elegantly put. In fact "sudden" more reasonably applies to the discovery and its publication, rather than the ozone hole, which as the graph shows ramped up over about 10-15 years.

(William M. Connolley 17:07, 13 Apr 2005 (UTC)) Reword looks OK - thanks. I think that the bit about the satellite data being dismissed as a measurement error is probably a bit more subtle than the wording indicates, but I can't lay to hand the "truth" if there is any.

I expect so! ... and I am not quite happy with the phrase "measurement error". I'm really going on what is says elsewhere in the article (History) and my fading memory of what was in New Scientist and Horizon at the time. Whatever the cause, there certainly was "a great deal of interest". Thincat 09:10, 14 Apr 2005 (UTC)

I've found this at [3] which pretty much the same as this article with a bit more detail.

"When was the ozone hole discovered?

Ozone depletion by human-produced CFCs was first hypothesized in 1974 (Molina and Rowland, 1974). The first evidence of ozone depletion was detected by ground-based instruments operated by the British Antarctic Survey at Halley Bay on the Antarctic coast in 1982. The results seemed so improbable that researchers collected data for three more years before finally publishing the first paper documenting the emergence of an ozone hole over Antarctica (Farman, 1985). Subsequent analysis of the data revealed that the hole began to appear in 1977. After the 1985 publication of Farman's paper, the question arose as to why satellite measurements of Antarctic ozone from the Nimbus-7 spacecraft had not found the hole. The satellite data was re-examined, and it was discovered that the computers analyzing the data were programmed to throw at any ozone holes below 180 Dobson Units as impossible. Once this problem was corrected, the satellite data clearly confirmed the existence of the hole." Thincat 10:14, 14 Apr 2005 (UTC)

The importance of being Bromine...

(William M. Connolley 22:01, 7 Jun 2005 (UTC)) Which, it would seem, doesn't apply to SEW. Sigh. But anyway:

On a per atom basis, bromine is even more efficient than chlorine at destroying ozone, but there is much less bromine in the atmosphere at present so it is less important overall (although still significant.)

SEW removed the bolded bit, apparently under the misaprehension that it was a judgement. It isn't. It means that effect times quantity is less.

Somehow bromine being less important overall than chlorine doesn't seem right: "…Cl compounds to destroy over 17% of the ozone, while bromine compounds deplete another 33%." Should the relative ozone effects Br:Cl ratio be mentioned? 21:1, it think it is, but I'd have to look it up. (SEWilco 00:29, 8 Jun 2005 (UTC))

I believe that the sentence quoted above is incorrect. The AAOE mission concluded that 70 percent of the _observed_ depletion during the antarctic ozone hole was due to the ClO dimer cycle, while another 20 percent was due to the ClO/BrO cycle. That was a long time ago [Anderson, Toohey and Brune 1991], but I don't believe that things have changed qualitatively since. (Note that you can't break it down into chlorine vs. bromine anyway, since the principal cycle containing Br also contains Cl.) My recollection, from the days when I was following the primary research pretty carefully, was that it wasn't clear whether Cl or Br was more important at middle latitudes, but that their effects were believed to be comparable. (AFAIK, there is still no complete accounting for the mid-latitude trends.) So I thought it fair to say that chlorine was more important than bromine overall, since it's definitely more important in the antarctic and roughly comparable at mid latitudes. However, I'll put in a more neutral statement in its place. I also noticed that some of the reference links are dead and others are duplicated - I'll clean that up.--Rparson 17:39, 9 Jun 2005 (UTC)

The 33% number had gotten separated from source, so I added a link. And for the "effect times quantity" calculation, the Br:Cl effect ratio is 45:1.doi:10.1029/2003GL017745 Bromine seems somewhat important: "The observed decrease is driven by a large and rapid decline in methyl bromide, a brominated gas …" [4] (SEWilco 21:00, 9 Jun 2005 (UTC))

(William M. Connolley 21:10, 9 Jun 2005 (UTC)) I think SEW is misreading his source. It says:

4. Spring brings an increase of ultraviolet light to the lower antarctic stratosphere, providing the energy needed needed for the rapid catalytic break-down of ozone by ClO and its dimer ClOOCl. Another mechanism involving Bromine adds another 33% to the depletion total.

It doesn't provide the 17% value. I think SEW is calculating 50-33=17. But I think this is wrong: [5] is saying that Bromine increases the depletion by 1/3, not that Br depletes 33% of the total ozone.

William, your interpretation is almost certainly correct, because Brian Sparling used my FAQ as one of his principal sources ! In the corresponding section of the FAQ, which was based primarily upon the 1991 WMO/UNEP report and Anderson et al.'s 1991 review article, I said that the ClO dimer cycle accounted for about 70 percent of the observed depletion and that BrO/ClO accounted for "~20 percent". Presumably Brian came across a later estimate that upped BrO/ClO to 33 percent. I think it's extremely unlikely that BrO/ClO actually contributes more than ClO/ClO, since that would have caused a major stir in the community.

I did read "depletion total" as meaning "amount depleted from maximum" (x+33>50%). So is that meaning intended, or the meaning "total amount of depletion" (x+33=100%)? Anonymous author of preceding paragraph, is there any information more recent than 1991 that you can contribute to the chemistry article? Whatever the relative contribution, Br apparently is significant enough to have wagged the total effect downward. (SEWilco 18:22, 10 Jun 2005 (UTC))

(William M. Connolley 19:03, 10 Jun 2005 (UTC)) He is Rparson, who wrote the ozone FAQ, as the text and edit history would tell you

--Rparson 16:02, 14 Jun 2005 (UTC) I've now looked over the relevant sections in the 1994, 1998 and 2002 WMO/UNEP reports. For the antarctic, the estimates have not changed significantly since 1991. For the arctic, the BrO/ClO cycle is estimated to account for between 30 and 60 percent of the total depletion. It makes sense that BrO/ClO would be relatively more important in the arctic, since the free ClO concentrations are lower there (much less release of ClO from reservoir compounds since the clouds are less prevalent, etc. etc.) Note, however, that you cannot translate the relative effectiveness of the two cycles into the relative importance of Cl vs. Br, because both cycles involve Cl. Its a nonlinear, synergistic effect. In any event, these technical points are IMO well beyond the level of the wikipedia article. It's best to leave the article as it is now, with both Cl and Br stated to be "significant" but without trying to quantify their importance.

Std nonsense

Latest comment: 19 years ago8 comments3 people in discussion

An anon [147.240.236.9], who may well be User:Barwick, has been adding fairly standard skeptic nonsense to the page, & I've been reverting it as such. All his stuff seems to be based on Haroun Tazieff. His main point:

He was surprised to discover an article in the 1950 Annals of Geophysics reporting the existence of ozone holes above Norway in 1926 - years before CFC's were even dreamt of - and was astounded to find that the hole above the Antarctic was not the recent phenomenon ecologists claimed it to be. It was actually discovered as far back as 1957, he says, by the English scientist, Gordon Dobson, but it was only in the mid-eighties that satellite photos began to highlight it in a rather spectacular way.

is a std FAQ:

Subject: 6.) But I heard that Dobson saw an ozone hole in 1956-58... This is a myth, arising from a misinterpretation of an out-of-context quotation from a review article by Dobson. In his historical account [Dobson 1968b], Dobson mentioned that when springtime ozone levels over Halley Bay were first measured, he was surprised to find that they were about 150 DU below corresponding levels (displaced by six months) in the Arctic. Springtime arctic ozone levels are very high, ~450 DU; in the Antarctic spring, however, Dobson's coworkers found ~320 DU, close to winter levels. This was the first observation of the _normal_, pre-1980 behavior of the Antarctic ozone layer: because of the tight polar vortex (see below) ozone levels remain low until late spring. In the Antarctic ozone hole, on the other hand, ozone levels _decrease_ from these already low values. What Dobson describes is essentially the _baseline_ from which the ozone hole is measured. [Dobson 1968b] [WMO 1989]

Its item 6 at http://www.faqs.org/faqs/ozone-depletion/antarctic/

Barwick 21:13, 4 November 2005 (UTC)Reply

I hadn't registered until just now, that's why the IP address showed instead of the user name originally.

The posting that William M Connolley keeps vandalizing by completely deleting uses Haroun Tazieff only as one small part of the text. Whether or not Mr Connolley and his referenced page's claim that it is a misinterpretation is true or not is inconsequential (not to mention untrue). Dobson observed that the ozone varied from the expected 450 DU to 320 DU even back in 1956, and today (when the surface climate average happens to be warmer due to the natural variance of water vapor and other greenhouse factors, thereby cooling the stratosphere) we see variations even less than 320 DU. Mr. Connolley just proved my point, that the Ozone "Hole" was discovered before CFC's were introduced into the atmosphere in any quantity besides trace amounts. I contend (along with other scientists) that the insulating factors of water vapor and other natural greenhouse factors cause the surface temperature to remain warmer, while the stratospheric temperature to remain colder, allowing more formation of Polar Stratospheric Clouds which greatly promote ozone breakdown by natural and manmade Chrlorine and Bromine, AND that the natural causes of Chrlorine and Bromine are so much larger than the manmade causes, that regulation of manmade causes will have about as much impact as telling one guy in a fishing boat in the middle of the Mediterranean Sea that he can't spit over the side or he'll pollute the water.

Nevertheless, Mr Connolley CLEARLY violated the rules by completely reverting the entire page, deleting the numerous other parts of the text in his multiple revisions, in addition to text that I just defended in part here.

Sigh. This is all the same old stuff... ah well. Firstly, who is this Mr Connolley of whom you speak. Use my username or use WMC or use my correct title if you really insist on using a title. Secondly, you are completely mistaken about wiki's rules (and if you were right, you'd have broken them yourself by your revert).

Your point (that the Ozone "Hole" was discovered before CFC's were introduced into the atmosphere) is rubbish. Did you even read the text I pasted above? The 320 DU that Dobson observed is not a hole at all: it was the pre industrial baseline state. As the quote clearly states. From the same source, here is a table of ozone values:

 Halley Bay Antarctic Ozone Data

  Mean October ozone column thickness, Dobson Units,
  as measured at the British Antarctic Survey station
  at Halley Bay (Latitude 76 south, Longitude 26 west)

   1956      321          1971      299 	  1986      248 
   1957      330          1972      304          1987      163   
   1958      314          1973      289          1988      232   
   1959      311          1974      274          1989      164   
   1960      301          1975      308          1990      179   
   1961      317          1976      283          1991      155   
   1962      332          1977      251          1992      142   
   1963      309          1978      284          1993      111   
   1964      318          1979      261          1994      124   
   1965      281          1980      227          1995	    129
   1966      316          1981      237          1996	    139 
   1967      323          1982      234          1997      139
   1968      301          1983      210           
   1969      282 	   1984      201 
   1970      282 	   1985      196

See how they atart at 320, pre-hole; and decline now to little more than 100.

Also that the natural causes of Chrlorine and Bromine are so much larger than the manmade causes is also nonsense. You've been reading too much Fred Singer, though even he doesn't believe that any more.

Singer? "The earth is not warming - Singer?"

This Singer? List_of_scientists_opposing_global_warming_consensus Artoftransformation 12:00, 6 November 2005 (UTC)Reply

Oh yes, same old nutty Singer. But even he doesn't believe the natural causes stuff (and didn't in 1995 either: http://www.sepp.org/ozone/ozonefranklin.html. Note that you have to read that pap carefully: its written to be full of quibbles to decieve the unwary) William M. Connolley 12:50, 6 November 2005 (UTC).Reply

I've removed your gross vandalism; someone else please revert the rest of his changes.

William M. Connolley 21:55, 4 November 2005 (UTC)Reply

Barwick 22:50, 4 November 2005 (UTC) Oh ok, so expecting a value of 450 and getting a value of 320 isn't a hole (or a thinning, like the present day "hole" is)...Reply

Sigh. Read it more closely: Springtime arctic ozone levels are very high, ~450 DU; in the Antarctic spring, however, Dobson's coworkers found ~320 DU, close to winter levels. No one has ever measured 450 spring in the antarctic. Dobson, initially, assumed that antarctic values would look like arctic ones. He quickly found that the assumption was wrong, based on his measurements. Values remained stable above 300 for decades, *then* started to decline to ozone-hole values in the mid-1980's, reaching 150-ish values. The data is there in the table: can you not read it?

All this is a misunderstanding, based on a misreading of an old paper. William M. Connolley 22:59, 4 November 2005 (UTC).Reply

Barwick 00:26, 5 November 2005 (UTC) WMC - You have a basic understanding of Discrete Mathematics, do you not? Here, let me show you: An event "A" happens. 9 months later, event "B" happens. Did "A" cause "B"? Maybe, maybe not. Let's examine:Reply

- If event "A" is, say "the dirty deed", and event "B" is "a baby is born", then based on 6,000 years and billions upon billions of similar events, we can reliably say that yes, indeed, "A" did cause "B".

- Now, if event "A" is the winding of a clock, and event "B" is the clock stopping ticking, then did "A" cause "B", kind of, but not necessarily, it could have reasonably happened by other means (perhaps the clock broke, or someone's hand hit the pendulum and stopped its motion).

- Now, if event "A" is a baseball going through the window of an old run-down abandoned barn that's falling apart, and event "B" is the discovery of a family of raccoons living in the barn, did "A" cause "B"? It's extremely difficult to tell. Perhaps the family of raccoons entered the barn by the broken window. Or perhaps they entered it in one of the other thirty-six holes all throughout the barn, how do you tell?

There's many more explanations, and saying that you know for sure that the raccoons living in the barn were caused by the kid playing baseball in the field, would be utterly ridiculous, when there are plenty of other valid reasons to explain why they are there. It is MUCH the same way with your assertion that manmade CFC's are causing the hole in the ozone. You look at a correlation and assume that it implies causation. If you were walking down Main street on Tuesday at 8:27 and someone was murdered at 8:29 on that same day on Main street, does that mean that you caused his murder? No, it simply means that the two events happened at the same time.

OK, we are (it seems) making some progress. Faced with the data, you are now abandoning your assertion that the ozone hole was found by Dobson. Thats good. You're now retreating to "yes the ozone hole occurred when cfc were emitted, but thats pure coincidence". This is a very weak position, which you'll have to abandon too. The chemistry etc is pretty well known and explained on the page and in the FAQ. I suggest you read it, and abandon your vandalism. William M. Connolley 10:06, 5 November 2005 (UTC).Reply

Barwick's insertions

Latest comment: 19 years ago11 comments6 people in discussion

You said that your material was well-referenced, but you failed to provide a ref (only a link to geocities). Please provide an appropriate link to the literature here. In addition, your edits do not conform to the MoS, which requires an introductory paragraph. Guettarda 02:09, 5 November 2005 (UTC)Reply

Folks, can I point out that Barwick is spamming the same nonsense into ozone layer [6] - please rv there William M. Connolley 10:07, 5 November 2005 (UTC).Reply

It's perhaps not as relevant, but he's also been making sweeping POV changes to Creationism, suggesting, without citing sources, that since there are a large number of comets in orbit around the sun, these must have been recently placed there. [7]. And I notice he's been using the 'vandal'-template at the top of pages here too, apparently under the impression that he is reporting vandalism. -- Ec5618 12:14, 5 November 2005 (UTC)Reply

Ah well, on the plus side she won't last long at this rate... William M. Connolley 14:09, 5 November 2005 (UTC)Reply

Despite all this, perhaps it raises a decent point. Perhaps a paragraph or so should be written succintly debunking the argument. [8] - Roy Boy ⁸⁰⁰ 04:23, 6 November 2005 (UTC)Reply

Unless its already there. (yeah I haven't read the article yet :D) - Roy Boy ⁸⁰⁰ 04:27, 6 November 2005 (UTC)Reply

Barwick 04:34, 6 November 2005 (UTC) Guettarda: where do you see that I'm not providing any references? The references already existed at the bottom of the article (http://www.sepp.org/ozone/ozonefranklin.html), one portion of the reference says:Reply

It is generally agreed that natural sources of tropospheric chlorine (volcanoes, ocean spray, etc.) are four to five orders of magnitude (1,000 to 10,000 times) larger than man-made sources - Maduro, R. A.; Schauerhammer, R. The holes in the ozone scare. Washington, DC: 21st Century Science Associates; 1992.

Sorry for not explicitly stating "read the link at the bottom", I'll do that next time.

In an attempt to keep this focussed, I've deleted the comets discussion - anyone interested should go over the the creationism article. But thanks to Ec5618 for alerting us.

Meanwhile, following Royboys idea, I've added a couple of "myths". William M. Connolley 10:31, 6 November 2005 (UTC).Reply

I helped! :D - Roy Boy ⁸⁰⁰ 22:30, 6 November 2005 (UTC)Reply

With regards to Barwick's comment to me - I am baffled. How can you claim something is "referenced" when you make no attempt to connect an assertion with a reputable source? You did cite a web page entitled "Greenhouse Bullcrap" for all your comments; although the name of the webpage probably does a good enough job of undermining its credibility, the fact that it's the personal webpage of a "Professional Audiovisual Operator, Driver, Handyman, Theatre Manager and Set Builder" pretty much confirms its scientific credibility. Where is Tazieff's work published? You are citing material you have read and evaluated yourself, right? Everything you added is unsourced - and claiming that it's supported by source you didn't even refer to seems less than honest. In addition, the Singer document does not mention mention Tazieff either - so how could that be your reference? Guettarda 06:11, 7 November 2005 (UTC)Reply

Don't worry too much Guettarda. Check Special:Contributions/Barwick. You'll see Barwick has a history of attacking articles such as Abortion, Creationism, etc., etc. Its best to just move along as he doesn't seem to editing in good faith, but rather using wikipedia for advocacy. --Quasipalm 16:11, 9 November 2005 (UTC)Reply

History of the Research

Latest comment: 19 years ago1 comment1 person in discussion

After expanding the "history" section, I decided that my additions had created a lot of redundancy with the succeeding "Ozone-oxygen cycle" section. Rather than edit the latter, I moved the "history" section way back - after "Consequences" and before "Controversy", so as to keep all the straight Science sections together. If anyone can think of a better place to put it, go ahead and move it. I will probably expand it a little bit more - add more about the experimental verification of the early Molina-Rowland work, and more about the history of the ozone hole. --Rparson 23:57, 29 November 2005 (UTC)Reply

UVA Major cause of cancer

Latest comment: 19 years ago1 comment1 person in discussion

I've put in a reference to the paper, which as far as I can see hasn't generated much in the way of controversy amongst the scientific community. You can find a discussion of the man and his work here. [9]

I have expanded the discussion and added additional references. It is important to distinguish among the various forms of skin cancer. The most common forms, basal and squamous cell carcinomas have been pretty conclusively linked to UV-B. These cancers are relatively easy to treat (although squamous cell carcinoma often requires the removal of a lot of skin, resulting in extensive reconstructive surgery.) The case is much less clear when it comes to malignant melanoma, which is much less common but far more dangerous. Most likely both UV-B and UV-A are involved, but their relative importance is not clear. I have added a reference to a review by Frank de Gruijl which summarizes the various lines of evidence. Note that Setlow was one of the peer reviewers of this article.Rparson 02:58, 2 February 2006 (UTC)Reply

Controversial Article?

Latest comment: 19 years ago2 comments2 people in discussion

Should someone add the Controversial Article bit? I think that if there is this much discussion, then it should be present.— Preceding unsigned comment added by Gharkib (talk • contribs) 04:45, 19 February 2006 (UTC)Reply

Why should this be tagged controversial? The article is stable (and reflects reality), the talk is thin. William M. Connolley 11:44, 19 February 2006 (UTC).Reply

Rework?

Latest comment: 19 years ago3 comments2 people in discussion

This article is a disaster, mixing together ozone depletion (mid-latitude weakining of the ozone layer by ~15%) with the polar ozone hole phenominon. They are different mechanisms and must be differentiated. I am going to start reworking the article tonight unless someone can give me a good reason not to, and that is going to be very, very hard to find.

Josh Halpern

Probably a fair point. It might be agood idea to do the re-work in a temporary space, like this: Ozone depletion/tmp if its going to take a while (ps: sign your talk edits with ~~~~. William M. Connolley 16:43, 23 February 2006 (UTC).Reply

From the history, I see that there were originally two separate articles on ozone depletion and ozone hole, but that they were merged at some point. It might be a good idea to separate them again - let the present article (with most of the more detailed Ozone Hole information removed) be the framework for an Ozone Depletion article that only describes the Ozone Hole briefly, and spawn a separate article for Ozone Hole. I also have always thought it odd that Ozone-Oxygen Cycle gets a separate article but I don't object to keeping it thus (it has actually matured into a pretty good article, brief as it is.) --Rparson 21:06, 23 February 2006 (UTC)Reply

I think I may have been guilty :-( But that doesn't mean I won't reconsider my sins :-) William M. Connolley 19:59, 24 February 2006 (UTC)Reply

It probably made sense at the time. The article has grown a lot longer since then, and it may be time for a split. That would help to make the overall level of the article more uniform, too. I'll wait until Josh is done with the main article, then put together a draft of an Ozone Hole article. It might be a good idea to have a separate article on Consequences of Ozone Depletion too.

Ozone Hole Repair and Ozone Seeding

Latest comment: 19 years ago2 comments2 people in discussion

It doesn't appear as if this article has any information on the viability of "repairing" the ozone hole or in the very least undoing human induced reductions in the ozone layer. To what extent is this possible and/or viable? I simply don't know enough about it and couldn't find much info from a brief search. [10], [11]

Having made the above caveat, I'm wondering if you could someday repair the hole or preempt the damge from ozone depleting chemicals that have yet to be released or work their way into the upper atmosphere. I'm thinking of some kind of massive project that would involve (possibly nuclear powered aircraft) releasing large quantities of chemicals to stimulate ozone production in sunlight or the brute force approach: Anywhere from dozens to thousands of robotic or remotely controlled nuclear powered aircraft would continually circle the south pole generating large amounts of ozone from atmospheric O2 and keep it up until the hole was repaired to the state it was before human induced reductions, or for good measure even thicker. Even if that is viable when will the global economy be able to afford it and is the benefit compelling enough? How might nanotechnology be able to repair it? Could we somehow induce lightning in the upper Antarctic atmosphere to do the trick? Maybe I watched too much Star Trek, but I'd like to think it possible for us to "fix" what we "broke".

...Hmmm... Maybe my search was a little too brief. A more thorough search turned up a few interesting articles about repair and I've linked some of them in the main article under external links. Maybe there should be a section in the main article about repair and other solutions and their viability? Most "repairs" don't really repair, just stop or slow the destruction of the ozone and thereby speed up the natural return.

I *was* going to reply that repair just can't be done. In fact I still think thats true, in any practical way, but maybe some people have pondered how it might be done, in theory William M. Connolley 10:17, 5 March 2006 (UTC)Reply

About 15 years ago, Ralph Cicerone published a speculative proposal for reducing the concentrations of Cl radicals in the stratosphere. The basic idea was to release several planeloads of propane or butane into the stratosphere. These would convert the active, ozone-destroying Cl radicals into inactive HCl (basically reversing the process that causes the polar ozone holes). The procedure would have to be repeated each year, though, since the Cl would not be removed, but only sequestered. Cicerone made it clear that he wasn't putting this out as an action item but rather trying to get people thinking about the problem, in the event that ozone depletion should turn out to be much worse than was thought at the time. There's a brief summary with references in the FAQ (Part III).--Rparson 22:43, 6 March 2006 (UTC)Reply

Less politics, more science

Latest comment: 19 years ago6 comments3 people in discussion

A brief glance at this article did not show me how much ozone there was in the atmosphere, much less how much has been "depleted" in the last 50 years. I did see a lot of verbiage about how the "observed" depletion of ozone justifies the Montreal Protocol's curbs of CFC usage.

Would the article please address observations of ozone concentrations in various places and at various altitudes?

Secondly, if ozone blocks Ultraviolet light in the "B" range (UVB), and since UVB causes certain kinds of cancer, could we please also have some measurements of UVB reaching the surface? Or at least UVB detected by instruments flown, aloft or in orbit?

In fact, the majority of so-called "stratospheric ozone measurements" are really UVB measurements of some sort. The ground-based Dobson and Brewer spectrophotometers measure the intensity of UV-B at several wavelengths, relative to intensity at several UVA wavelengths, and use this to calculate the ozone column. The satellite-based instruments (TOMS, et al.) measure UV scattered back from the ozone layer. Of course these are not direct measurments of total surface UVB - those are very difficult (as I'm sure Halpern can tell you at great length, absolute light intensity measurements are very tough to do even in a controlled lab environment, let alone in the field). But I think the case could be made that the connection between TOMS or Dobson-Brewer data and surface UV-B is at least as secure as the connection between the MSU data and tropospheric temperatures.

I do have some references to direct surface UV-B measurements in Part IV of the Ozone FAQ, and it would probably be useful to put some of it in the article. The problem is, the article is already getting unwieldy and it would probably be better to wait until we've decided about whether to break it up into several articles. --Rparson 20:22, 10 March 2006 (UTC)Reply

Its been suggested and no one has objected. I think you should Just Do It William M. Connolley 20:34, 10 March 2006 (UTC)Reply

Published claims (in Science, 262:1032, 1993) that UV-B is increasing at 35% per year were later shown to be false (Science, 264:1341, 1994) [12]

I wonder if the current article takes into account the 1994 correction (in Science) to the highly-publicized but erroneous 1993 paper. --Uncle Ed 20:50, 8 March 2006 (UTC)Reply

I wouldn't trust a word that Singer writes. But Rparson will know better. I'll look up the Science papers tomorrow at work, and if forced to eat my words, well... chomp chomp William M. Connolley 00:22, 9 March 2006 (UTC)Reply

Ah, predictably enough my words are safe and Singers are... well, distinctly dodgy is being kind.

Evidence for large upward trends of ultraviolet-B radiation linked to ozone depletion by J B Kerr and C T McElroy, Science 262:1032 is the original article

Analysing ultraviolet-B radiation: is there a trend? by P J Michaels, S F Singer and P C Knappenberger, Science 264:1342 is a comment

Kerr and McElroy then reply, affirming their original findings and pointing out problems with the comment. Odd that Singer didn't find time to mention that, eh?

In my opinion, there was some underlying substance to the criticism of Michaels et al., which unfoturnately was obscured because they tried to push it way too far. Kerr and McElroy should not have used the word "trend" in their title, because to most people that implies some sort of long term observation which is not at all what K&M did. What they did observe could more properly be described as a "response". The background here is that during the spring of 1993, ozone levels over high northern latitudes underwent a dramatic decline, which has been convincingly attributed to heterogeneous chemistry on the sulfate aerosols from the Pinatubo Eruption. K&M observed that when the ozone-depleted air arrived over their station (following the breakup of the arctic vortex), their surface UV measurements went sharply upwards, exactly as expected. Similar observations were made from stations in Greece and in Germany (references in the FAQ). This is actually more useful than a mere trend observation, since it provides information that can be used in calibrating the quantitative relationship between total surface UV and stratospheric ozone. If Michaels et al. had focussed on the difference between "trend" and "response" they could have made a valuable clarification since the title and abstract of the K&M paper don't spell this out at all clearly. Unfortunately they jumped to conclusions and tried to attribute the whole observation to a statistical fluke. And once again, they pick out a single paper from a large and mutually reinforcing body of literature. I've never seen Singer mention the Greek or German papers, or the Reply to their comment, or Weatherhead's extensive reanalysis of the US Robertson-Berger meter measurements. --Rparson 20:22, 10 March 2006 (UTC)Reply

So shown to be false is junk. Correction is technically the wrong term William M. Connolley 11:41, 10 March 2006 (UTC)Reply

New fact in intro

Latest comment: 19 years ago3 comments3 people in discussion

I am not convinced that it is an approriate use of the WMO report to use as the second sentance of this article the least worrying of all the many statistics in the executive summary. I would rather use several of them. I think the whole lead section is now a mess with too much detail. I also think we need to decide whether the intro needs references for things which are properly referenced in the main body.

Oh and the key responsibility for the report is WMO and UNEP not NOAA (although they are co-authors and have the report on their website). I have now fixed this. A new WMO/UNEP report is currently in preparation.--NHSavage 22:54, 9 March 2006 (UTC)Reply

Well, I just wanted to make it clear that there hasn't been a 50% loss of depletion over 50 years - just 3% or (whatever tiny fraction it is). I put the first fact I could google into the intro. The article itself didn't provide any numbers I could see. --Uncle Ed 23:51, 9 March 2006 (UTC)Reply

I think the figure showing composite Nimbus-7 and Earth Probe TOMS measurements of global ozone answers most of Ed's questions, since it illustrates the long term trend together with the seasonal oscillation. I've copied it up to the top - it's a more appropriate figure to go with the introduction than the ozone hole image, which I've moved back down. The intro still needs a rewrite - I will take this up this weekend unless someone else gets to it first. In general the article is getting pretty long and should probably be broken up into three - Ozone Depletion, Ozone Hole and Impacts of Ozone Depletion.

Don't forget to take a quick glance at Ultraviolet light and cancer William M. Connolley 19:47, 10 March 2006 (UTC)Reply

Qs from Isabelle Hakala

Latest comment: 19 years ago2 comments1 person in discussion

This from mine and her talk page:

Hi, I am a total nubie, so please forgive me if I didn't put this in the correct place. my user is: ismirth, in case you need it. I was reading the ozone pages (many of them) and I was wondering if there is some other phenominon that might be being overlooked? I guess I just couldn't tell if there was really less ozone /everywhere/, not just at the hole. If the entire global ozone content has gone down, then I would like to see those stats (or maybe they are there but I need them dumbed down:)). Because it seems that maybe the air currents have changed in a way that makes there be less ozone of the hole, but more ozone someplace else on the planet.

Since we have a fairly good understanding of what is going on, its not clear why you should be looking for anything else to explain it... William M. Connolley 18:08, 3 May 2006 (UTC)Reply

Interestingly, I am actually totally a believer in the hole in the ozone, but I like to debate and that was the only (opposite) view that I haven't found an clear (to me) answer to.

Also, and this might be naive, but why can't we just dump a bunch of ozone into the stratosphere to help it out, in the mean time, until we can get our greenhouse gases lower? Is it possible, but cost prohibitive? Or is there some other reason?

Ozone is created and destroyed. Adding more would not help unless done continuously which would be absurdly difficult. William M. Connolley 18:08, 3 May 2006 (UTC)Reply

And I know you said to check back here for your answer, or to put a request here to go my talk pages, (which is what I wanted to do), but I can't figure out how to create the talk page. It gives a link for creation of new pages, but talkpages weren't listed there. It seems really unclear and convoluted to me (so does adding comments to the discussion pages, which is why I came here to do it instead, where I hope that you are more forgiving if I mess something up:)) Anyways, if you can look at my talk page, and if by some miracle I got it working, do you think you could leave a copy of your response there? thanks:) -Isabelle aka ismirth

There are always new ways to see things... Isabelle Hakala

Latest comment: 19 years ago2 comments2 people in discussion

Hi William,

I know I didn't say it before, but I am a scientist (Biologist), and I believe that if there is dissent on a topic, then one should thoroughly peruse both sides of said topic. This is what makes for good (non-hostile) debates, and makes people far more persuasive in their opinions. I also know, that many of the scientists of the past have felt they had a "a fairly good understanding of what is going on, [so] why ... look for anything else to explain it..." (the world is flat, sickness is caused by humors, there is no such thing as invisble bugs that can make us sick... etc) and well, that just doesn't fly as a life choice for me:) I don't want to make assumptions based on other peoples beliefs. I don't want to just take someone else's word for it. I want to be shown the evidence, perhaps have it explained to me, and work it out for myself. That is what makes a responsible scientist and human. A sense of curiosity, innovation, and open-mindedness, often creates profound growth and movement forward in any field.

I understand that you have been having a wiki-war with someone about this topic, and that isn't what I am looking for. So I apologize if made you feel that you need to defend the majority's viewpoint, it wasn't my intention. I was just hoping for a distilled answer that would help me have a conversation about the ozone layer with others (especially people who think it is a sham). Having the answers to those questions would show that I had taken the time to think through their side of the topic, and that often defuses hostilities. As we explore possibilities, and discard them for ourselves, it instills in others a faith and trust in our process.

With that in mind, I wanted to say that just because I said I was a newbie at wiki, and naive on /this/ topic, doesn't mean that I am not smart in other areas, nor that my questions wouldn't be good ones. It might calm your wiki-war down a bit if you collated the information that I was asking about and used it to,perhaps, convince the other person. That is basically why I wanted it for myself. Shifted air-currents is the only explanation I could come up with that someone might be able to use to delude themselves of our situation and so I wanted to be informed *enough* to perhaps sway someone in the general direction of helping to clean up the damage we have wreaked upon our atmosphere (instead of continuing to add to it).

If you are confident and comfortable with your understanding of the topic, they why not explore it with others? I don't mind being shot down by being given a clear (or clearer) view of the facts, and I had hoped to find someone to enlighten me in this topic.

Sincerely, Isabelle Hakala 08:17, 4 May 2006 (UTC)Reply

There is no (credible) dissent on the physics of this. I'm really not sure what you are referring to. And... what wiki-war? William M. Connolley 08:35, 4 May 2006 (UTC)Reply

Ozone depletion question

Latest comment: 19 years ago1 comment1 person in discussion

Hi, I was reading the ozone pages (many of them) and I was wondering if there is some other phenominon that might be being overlooked? I guess I just couldn't tell if there was really less ozone /everywhere/, not just at the hole. If the entire global ozone content has gone down, then I would like to see those stats (or maybe they are there but I need them dumbed down:)). Because it seems that maybe the air currents have changed in a way that makes there be less ozone of the hole, but more ozone someplace else on the planet.

Interestingly, I am actually totally a believer in the hole in the ozone, and global warming, but I like to debate and that was the only (opposite) view that I haven't found an clear (to me) answer to.

Also, and this might be naive, but why can't we just dump a bunch of ozone into the stratosphere to help it out, in the mean time, until we can get our greenhouse gases lower? Is it possible, but cost prohibitive? Or is there some other reason?

I have also left this question on my talk page, but I wasn't sure how to link to back to it. Can you put a link on my talk page pointing at your response? thanks:) --Isabelle Hakala 09:02, 3 May 2006 (UTC)Reply

Ozone hole

i am doing a school project and looked up ozone hole and it gave me ozone deepletion, please make a seperate article for ozone holes

      Thanks,
         Travis

Sane or Insane Formula?

Latest comment: 19 years ago1 comment1 person in discussion

I have made a slightly odd formula in TeX. Could someone prove it right or wrong, because I have included the gamma wave factor of ozone destruction only. I am new to formula writing - take it easy on me!PSv255 22:39, 5 June 2006 (UTC)Reply