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UNITE! Info #166en: 7/8 The "ozone hole" terror hoax [Posted: 20.03.02] [Continued from part 6/8] 17. THE ANTARCTIC "OZONE HOLE", A FAKE "THREAT" As said under point 08 above, over the higher latitudes (more precisely, over what the WMO calls "the midlatitudes", bet- ween 25º and 60º or so), the annual mean level of ozone is somewhat higher than over the tropics, 300 DU over the USA and some 330 DU over Sweden, for instance, compared to 220- 250 DU close to the equator, and seasonal variations there are quite large, in contrast to over the tropics, where the ozone layer thickness always remains at those 220-250 DU. The ozone layer over Sweden is at its thickest in the spring (March-May in the northern hemisphere), between 350 and 450 DU then, says the SMHI (see point 06 above), and in late au- tumn often thins out to below 300 DU. Day-to-day variations are even larger, with for instance that all-time high of 574 DU over mid-Sweden (58º N) on 23 February 2001, the recent reading of 557 DU on 2 March 2002 too, both considerably above the former all-time high of 536 DU in April 1961, and also the all-time low over Sweden at only 194 DU on 30 Novem- ber 1999. It's mainly transport of ozone with the winds from the tro- pics that accounts for these large variations. Equally large, and sometimes even larger, variations in the thickness of the ozone layer there are over the Arctic and the Antarctic regions (at latitudes higher than some 70º N respectively 70ºS). In these regions close to the respective Poles, there are particular meteorlogical vortices, approxi- mately circular or elliptical currents which at some points in the seasons may more or less prevent the influx of ozone- rich air from the lower latitudes. The vortex over the Ant- arctic is much stronger than that over the Arctic, which is impeded by chains of mountains. Over the Arctic, the ozone layer varies between some 480 DU in the (northern) spring and some 260 DU in the autumn, as already measured by Dobson back in the 1950s. The correspon- ding seasonal dip in the level of ozone over the Antarctic, which occurs in the southern spring, in September-October each year, is much deeper than the Arctic one. A table by Parson (whose data I shall complement a little in the below) shows approximately how deep it was in the years 1956-1997: [QUOTE:] 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 Data from J. D. Shanklin, British Antarctic Survey, personal communications, 1993-95. [END OF QUOTE] As is seen, from approximately the late 1970s on and up to the early 1990s, there was a tendency for the September-October dip to get deeper year by year, and up until 1997 at least, it stayed at a level considerably lower than the mean one of pre- vious years. The difference between that level and the earlier mean one is what the "ozone depletion" propagandists are cal- ling "the Antarctic ozone hole". Parson writes too that "There is no question that the ozone layer over antarctica has thin- ned dramatically over the past 15 years" and that: "The antarctic ozone hole, discussed in detail in Part III [of the 1997 'FAQ'], falls far outside this range of natural variation [the one of seasonal such else- where - RM]. Mean October ozone at Halley Bay on the Antarctic coast was 117 DU in 1993, down from 321 DU in 1956." On whether an Antarctic October ozone level mean of 117 DU (or 111 DU - see table) actually does "fall far outside the range of" earlier natural variation or not, see further below. The term "ozone hole", for this greater depth of the Septem- ber-October level dip, of course is a propagandistic one. More precisely, the WMO defines as an Antarctic "ozone hole" a region over which there, during a certain seasonal period, is less than 50% of the ozone which there there was on the average over the same region, during the same seasonal period, in a number of years which the WMO takes as "the norm", those between 1964 and 1976. Parson on his part says: "Let us de- fine the 'hole' to be the region where the total ozone column is less than 200 DU, i.e. where total ozone has fallen to less than 2/3 of normal springtime antarctic values", meaning by "normal springtime values" the average ones before 1980, which he thus estimates to have been some 300 DU. If the thickness of the hull of a ship, for instance, or of the fabric of an umbrella or a raincoat, at some point is less than 50% or 2/3 of that of the hull respectively the fabric elsewhere, nobody calls that "a hole". Such similes are not quite perfect of course, since the ozone layer "umbrella" at no point in its area is "watertight" anyway but everywhere lets *some* ultraviolet radiation through. But anyway, the Antarctic ozone "hole" is something quite different from what you normally mean by "a hole". Is this "hole" caused by chlorine then, in that case largely by such from CFCs, the releases of which undoubtely have in- creased the concentration of chlorine in the global strato- sphere as a whole? Parson says yes, that this "has been proved", and recounts how, by a complicated process, largescale depletion of ozone takes place over the Antarctic each September-October, pur- portedly with chlorine as a decisive agent. As the "most important proof" of this, Parson cites: "The 'smoking gun' is usually considered to be the simultaneous in-situ measurements of a variety of trace gases from an ER-2 stratospheric aircraft (a converted U2 spy plane) in August-October 1987. [Tuck et al.] These measurements demonstrated a striking 'anticorrelation' between local ozone concentrations and ClO concentrations. Upon entering the ozone hole, ClO concentrations sud- denly jump by a factor of 20 or more, while ozone concentrations drop by more than 50%. Even local fluctuations in the concentrations of the two species are tightly correlated. [Anderson et al.] The correlation is quantitatively accurate: from the measured local ClO concentrations together with reac- tion rate constants measured in the laboratory, one can calculate ozone destruction rates which agree well with the measured ozone concentrations." Bidinotti (writing in 1994) agrees with the chlorine theory concerning that particular region, the Antarctic, but argues that significant ozone depletion due to that substance can- not take place elsewhere, describing briefly how, according to his understanding of it, the particular Antarctic process works: "The [Antarctic] 'ozone hole' is a temporary, chlo- rine-enhanced thinning of the O3 layer over Antarcti- ca during our (northern) autumn months. It requires the following meteorological ingredients: (a) a lengthy polar 'night' -- i. e., a prolonged absence of UV radiation. This allows (b) the buildup of chlo- rinated compounds, unmolested by UV, in the (c) "po- lar vortex" -- a vast, self-contained whirlpool of air over the Antarctic region. The vortex largely isolates polar air from mixing with air outside the region, thus diluting the chlorine concentrations. Now add (d) super-cold, high-altitude temperatures, which causes ice clouds to form in the stratosphere. The ice crystals provide surfaces upon which chemical reactions between chlorine and ozone can take place much more rapidly and efficiently than by mere mixing in the air. Finally, add (e) the sudden appearance of the sun after the long polar night. This adds high levels of UV to the chemical soup, which breaks down chlorine compounds into their constituent elements -- such as highly reactive chlorine monoxide. The chlo- rine monoxide -- not the CFCs themselves -- then re- acts on the surfaces of the ice crystals with ozone molecules, breaking them down. A few weeks later, as the polar weather changes, the vortex breaks up, allowing the infusion of outside air into this chemical 'soup' -- and soon, all the reactions stop. Ozone is then rapidly and naturally replenished by solar UV action on oxygen, and the 'ozone hole' quickly refills. If ANY of these ingredients are absent, you won't have ozone depletion. And the ONLY place that has them all is Antarctica. Even the Arctic region does not have as well-defined and isolated a vortex, be- cause mountains there break it up. Nor do the strato- spheric temperatures there get as cold...which means you don't get an abundance of ice crystals to act as a catalyst for accelerating the chemical reactions. In February 1992, NASA held a news conference to an- nounce 'record levels of chlorine monoxide' over the Arctic, and to predict 'very significant ozone loss, 30 to 40 percent' within weeks. Capt. Planet (alias Al Gore) started moaning about the 'ozone hole over Kennebunkport' (George Bush's home), and got a law passed to accelerate bans on CFCs. But the 'hole' didn't exist then, and never occurred. The weak Arctic vortex broke up, the temperatures weren't cold enough...and there was no significant depletion. This lends empirical support to the skep- tic's case that ozone depletion can't occur to any significant degree outside of Antarctica, no matter *how* much chlorine monoxide gets up into the strato- sphere, from *whatever* source, natural or human. Bottom line: don't worry about a cancer epidemic from ozone depletion. It apparently takes more than just chlorine monoxide to destroy ozone: it also takes the right meteorological conditions...conditions that exist ONLY in the Antarctic, and ONLY during the au- stral spring (our autumn). By the way, lest anyone worry about Antarctic peng- uins: Don't. The amount of solar UV there at the height of the 'ozone hole' is even *less* than the amount during the Antarctic summer! Reason: the angle of the sun is much lower in the austral spring, when the 'hole' appears, than it is in the Antarctic sum- mer. For the same reason that you can't get a suntan at dawn, you get less UV in the spring than the sum- mer. Any animal that can survive the sun during the polar summer, can survive it during the spring 'ozone hole'." There are good reasons too to doubt that chlorine *is* the decisive factor *even* over that region, the Antarctic. Firstly, there is an argument by Hugh Ellsaesser (from 1990) saying that the Antarctic "ozone hole" is unlikely to become any more important than in it was in 1987. The fact that An- tartic October mean ozone levels during some later years *were* somewhat lower than that in 1987 (see table above) doesn't importantly contradict this, I hold; this may have been due to some factors such as the Mt. Pinatubo volcanic eruption in 1991. Secondly, there was such an "ozone hole" back in 1958 too, long before any important increase in stratospheric chlorine. (Parson - of course - makes no mention of this.) And thirdly, the "depletion" propgandists, in a manner simi- lar to their abovementioned tell-tale silence on all "global ozone depletion trend" "data" after 1998, in recent years "strangely" have refused to report what are the Antarctic Oc- tober mean ozone levels *now*, measured in Dobson Units (DU), among other things now, in recent years, employing other ways to characterize that "hole", such as "its" total area in km² or the "loss of ozone" "caused by" "it", measured in mega- tons. This smacks of confusion-mongering, intended probably to cover up actual results showing that this "ozone hole" is not "deepening" at all any more, or perhaps is even receding. I shall go into these matters in turn. Concerning the first, Maduro and Scauerhammer wrote in 1992 (pp. 142-143): "The final pillar of the dimer theory [the one on the Antarctic 'ozone hole' shown in brief above - RM] is knocked down by atmospheric scientists Hugh Ell- saesser, who points out in a recent speech (Ellsaes- ser 1990): 'The ozone hole...reflects a process which can occur only in those portions of the atmosphere which are maintained at temperatures below about -80º C (-122º F) for two to three months, during at least the lat- ter half of which, the must also be exposed to sun- light. Such temperatures occur only in restricted vertical layers, roughly 12 to 20 km, within the po- lar vortices which develop due to radiative cooling when sunlight is absent over the pole in winter, and at the tropical tropopause [the upper region of the troposphere, directly below the stratosphere - RM]. In 1987 the level of ozone within this cold layer over Antarctica fell essentially to zero - less than 5 percent of normal. In other words, the *maximum possible ozone hole occurred in 1987*. [As to October mean ozone levels, these were actually even somewhat lower, in some following years, than that of 1987 - see table above. But this may have been due to some part to the 1991 Mt. Pinatubo eruption, and/or to the 'ozone hole' in 1987 occurring not mainly in October; the later levels weren't much lower anyway and the 'hole' seems to have stabilized in 1994-1997. - RM] The phenomenon does not occur to any appreciable ex- tent over the North Pole beacuse the north polar vor- tex breaks up and rewarms about the same time as the Sun comes up there. Also, ozone loss is unlikely to ever be detected at the tropical tropopause both be- cause there is little ozone there to be destroyed and because the air there is constantly being flushed out by a slow updraft through the tropical tropopause. Thus, unless there are changes other than the simple addition of more chlorine to the stratosphere, the ozone hole does not appear likely to become any more important than it was in 1987. It should also be noted that the ozone hole merely causes ultraviolet fluxes at the surface over Antarc- tica in spring, comparable to what is experienced there every summer.' In other words, the so-called ozone hole is a self- limiting process, which had already reached its maxi- mum possible size and intensity in 1987 [see note above - RM] without producing harm to anyone or any- thing. Despite all the doomsday scenarios of a mons- ter ozone hole, adding additional chlorine to the stratosphere will not change anything except possibly to make the hole appear a little more rapidly every [southern] spring." 18. THE ANTARCTIC OZONE "HOLE'S" FORGOTTEN PAST, AND DOES IT HAVE A FUTURE? Why the Antarctic September-October ozone level dip (appa- rently) did deepen from the late 1970s on and then stayed at a rather low level as long as up to 1997 at least (see table under point 17 above) does remain a mystery to me. This can- not be explained by the 11-year sunspot cycle of course, nor by the meteorological 26-month air transport one, the QBO. The "CFCs ozone depletion" "theory" does not explain this be- haviour which that ozone "hole" showed in those years either. And I cannot see how certain other theories mentioned by Ma- duro and Schauerhammer in 1992, for instance two having to do with particular effects at the poles of the so-called solar wind, could do it. A relatively recent (17.09.2001) NASA report, while not gi- ving any figures on Antarctic ozone "hole" levels then, does present air transport over the globe, the so-called planetary waves, as a key factor in the formation and the depth of that "hole" in different years (comparing for instance the 1984 shallower dip to the 1997 deeper one), and treats the pheno- menon as a constant one over the years. Anyway, the Antarctic "ozone hole" clearly by no means poses a threat to human life, and it apparently would have been quite nice for practically everybody if it could be moved to the Arctic, giving countries in the rather far North a some- what better climate, as far as UV radiation was concerned, as pointed out by the 1989 Norwegian study cited under point 02 above. And an Antarctic September-October ozone level dip just as deep as those of some later years, that is, an "ozone hole" there, was observed as early as in 1958 too. Parson writes that "the antarctic ozone hole... falls far outside" the range of natural variation, "supporting" this by: "Mean October ozone at Halley Bay on the Antarctic coast was 117 DU in 1993 [or 111 DU, as his above table shows], down from 321 DU in 1956", and further that this "hole" was "first discovered in 1980-1984". He mentions "a myth" that "Dobson saw an ozone hole in 1956-58" and (easily) refutes this proposition. But that writer of the detailed 1997 "FAQ" blatantly lies about this matter. What Maduro and Schauerhammer (for in- stance) had said in 1992 was not that Dobson had made such a discovery in 1958 but that some French scientists had done that, at another measuring station than Halley Bay. They wrote at length on this in their 1992 book, which Parson must have known in 1997 but, revealingly, "forgets all about" in his 1997 "FAQ". Maduro and Schauerhammer, 1992, pp. 121-123: "...Dobson did not detect the steep September-October did we now identify as the ozone hole. But, as noted below, the French, at their Antarctic station at Du- mont d'Urville in 1958, did detect a steep September- October dip, down to values as low as 110 dobson units. The polar vortex - an enormous vortical structure - does not stay in one spot. It may move several times a month and moves many times in the course of a year. An atmospheric station near the edge of Antarctica may be within the vortex one year and outside the next year, and ozone concentrations will vary drama- tically. Inside the vortex, the values measured may be as low as 110 dobson units, while outside the vor- tex, just a few miles away, the values may be as high as 450 dobson units. These facts answer the main ar- gument of the ozone depletion theorists that man-made CFCs are responsible for the increase in the southern anomaly, the so-called ozone hole. Two French scientists, P. Rigaud and B. Leroy, re- cently republished the 1958 data from the French Ant- arctic station, Dumont D'Urville, located on the op- posite side of the South Pole, a few hundred miles from Halley Bay. These measurements show that the ozone hole was deeper in 1958 than at any time in the 1980s, but that it disappeared immediately after the breakdown of the 1958 polar vortex. [Continued in part 8/8] --------------------------- ANTI-NATO INFORMATION LIST ==^================================================================ This email was sent to: archive@jab.org EASY UNSUBSCRIBE click here: http://topica.com/u/?a84x2u.a9617B Or send an email to: [EMAIL PROTECTED] T O P I C A -- Register now to manage your mail! http://www.topica.com/partner/tag02/register ==^================================================================