First published as two posts to the Moderated Discussion of the Objectivist Philosophy electronic mail list postings of May 7, 1994. Some names in the text refer to individuals who posted comments online in this discussion.
Is our stratospheric ozone layer under attack by chlorine coming from man-made CFCs?
Paul Robinson's posting of March 24 on the subject of ozone depletion and CFCs is correct in its skeptical answer, but very wrong in how he arrives at that answer. I am concerned that, in a hasty effort to repudiate radical environmentalists, too many of "us" (following the lead of the late Dixy Lee Ray, Rush Limbaugh and others) are becoming susceptible to junk science and half- baked theories. The ozone controversy is a prime example.
I'd like to comment at length, because this issue shows that some of us -- relying too much upon a rationalistic, deductive method -- tend not to do our empirical homework on serious issues. We apparently think that it's enough to extend our philosophical principles deductively into various specialized controversies, and -- with only a smattering of facts at our disposal -- logically infer the "right" answers. This case vividly illustrates the pitfalls of that approach. So consider this posting not a side trip into the environmentalist controversy, but instead a case study focusing on the perils of poor methodology.
I was commissioned by Reader's Digest to investigate the "ozone depletion" controversy. Though the magazine did not publish the resulting article, my six-month investigation was a very thorough and eye-opening one. I spent considerable time, for example, visiting installations of the National Center for Atmospheric Research (NCAR), the National Oceanic and Atmospheric Administration (NOAA), and also NASA. I compiled a great deal of scientific literature on the subject, and interviewed dozens of the top scientists representing all sides of the controversy. I spoke not just with the political flunkies who run the research projects, but with many of the good, non-ideological, apolitical research scientists who are actually doing the field and lab work.
Almost at once, I was shocked to find that virtually none of the well-known scientific "skeptics" had done their homework. I was dismayed to discover, again and again, that I was providing these "experts" with relevant scientific papers and data, and not vice- versa. Though a non-scientist, I quickly realized that I knew more than they did. (Their ignorance, unlike mine, had not stopped them from publishing on the subject, however.)
I had begun my research holding opinions very similar to those expressed by Robinson, based upon a smattering of reading and my strong philosophical predisposition against environmentalism. However, my job as a journalist is to go wherever the facts, not my inclinations, lead me. I had expected to find that the ozone depletion "threat" was largely a scam. And in fact, that's what I found...but not in quite the way that Robinson and others claim.
It is absolutely true that "ozone depletion" is an absurd environmentalist bogey-man. There is no evidence that long-term global ozone levels are declining; there is no evidence that ultraviolet radiation levels reaching ground level are increasing; and even the declines in ozone projected by alarmists for the next thirty years would not result in ultraviolet exposure levels equivalent to one's moving about 100 miles south! Moreover, the so-called "ozone hole" cannot expand outside of Antarctica, because it is confined to that region by unique meteorological conditions. And one of NASA's own studies, conducted by Dr. Linwood Callis, found that the impact of CFCs on the ozone layer during the 1980s had been negligible.
So no, we aren't going to see any "cancer epidemic" in populated regions due to CFCs destroying our stratospheric ozone layer. It won't happen. (A summary of the facts appears in my booklet, The Green Machine. The ozone depletion controversy is just one of several major environmentalist scams I refute in the booklet, which is heavily documented.)
However, this said, there are several common skeptical arguments -- echoed by Robinson -- which are simply not true.
The presence of atomic chlorine in the upper atmosphere (stratosphere) has been established beyond doubt, through high- altitude balloon flights and satellite measurements. Moreover, atomic chlorine can and does react with ozone under the proper atmospheric conditions, breaking it down. There is also no doubt that, each September-November, chlorine collects in the region over Antarctica in very high concentrations. Again, there have been very thorough instrumental measurements of this phenomenon. The chlorine, in combination with weather conditions unique to the Antarctic atmosphere, does in fact temporarily destroy over half of the atmospheric ozone there each year. The scientific literature on all of this is empirically grounded and utterly convincing; I have a small mountain of it here in my office.
The next question is: Where does most of this chlorine come from -- natural sources or man-made chemicals? To Robinson, this is the main issue. His answer is that man-made chemicals, such as CFCs, are negligible in their impact compared with natural sources of chlorine. But he is again wrong.
This question has been scientifically settled. As early as 1985, instruments aboard the Space Shuttle determined beyond any doubt that very significant levels of chlorinated compounds were present in the stratosphere, and that the chemical signatures of these compounds could only be of man-made, not natural, sources. We are not talking about small percentages, either: a very large part of the stratospheric chlorine budget -- half or more -- was coming from man-made sources, not from volcanoes or oceanic evaporation.
The chemical signatures of these compounds were in fact those of CFCs. The spectrographic instruments aboard the Shuttle showed that actual CFCs -- not derivative compounds, but the CFCs themselves -- were present in the lower stratosphere in large amounts; that as altitude increased, the CFCs broke down into their unique constituent elements under the impact of solar ultraviolet (UV) radiation; and that, in turn, the amounts of these elements -- such as atomic chlorine and fluorine -- built up rapidly with altitude.
I have seen the altitude-based graphs of these signature chemicals; they are totally convincing. Other skeptics to whom I provided this data -- such as Dr. Fred Singer of the Science and Environmental Policy Project in Washington -- have been persuaded by this evidence, too, and have now abandoned the whole "natural vs. man-made" argument as a result.
Other evidence also fingers CFCs as a major source of stratospheric chlorine. Balloon measurements for years have been recording steady increases in the amounts of chlorine and fluorine in the atmosphere, and also in the stratosphere. To declare that "natural sources" are responsible for this, one would have to explain how and why natural sources would suddenly be spewing more of these elements into the air -- and in a stable-enough form that they could reach the stratosphere without first breaking down or precipitating out.
For example, given that oceanic evaporation is relatively constant, there would have to be an ever-increasing number of explosive, chlorinated volcanic eruptions to account for ever- growing amounts of stratospheric chlorine. Yet that hasn't been happening.
On the other hand, CFCs have been increasingly produced and released into the atmosphere; they are uniquely inert and stable, and thus have much longer "lives" in the atmosphere than do the naturally-produced chlorinated compounds, which tend to be more soluble and short-lived. The only thing in nature that can efficiently break down CFCs is the powerful level of UV radiation in the upper atmosphere; and when it does, the result is an increasing supply of its constituent elements, such as atomic chlorine and fluorine -- just as the satellite and balloon measurements show has been occurring.
Skeptics are simply barking up the wrong tree when they insist that "natural sources" are the cause of stratospheric chlorine, and are revealing their failure to do their homework. For example, it is true that volcanoes can pump chlorinated compounds directly into the stratosphere -- but only if the eruptions are explosive enough to propel the gases to extremely high altitudes, and even then, only if those volcanoes contain and expel chlorine. However, most volcanoes are neither explosive nor highly chlorinated: one that is both, is a rare geological event. Most, such as Hawaii's Mauna Loa, just steadily emit gases that are washed out in the lower atmosphere long before they ever reach the stratosphere.
The 1982 El Chicon eruption in Mexico was a rare volcano that was both explosive and highly chlorinated. By contrast, the St. Helens and Mount Pinatubo volcanoes of a few years back were not: the amount of chlorine expelled by both (contrary to inaccurate claims by Ray and Limbaugh) was relatively small. And even when such chlorine reaches the stratosphere, it steadily declines over time and, within five or six years, is "washed out." El Chicon had a temporary and measurable impact on global ozone levels; by 1986, the effect had disappeared.
In short, contrary to Robinson's claims, the "35,000 tons" of annual chlorine estimated to be expelled by volcanoes seldom reaches the stratosphere. Nor does the "600,000,000 tons" coming from the oceans. These natural chlorinated compounds are highly soluble, and almost all of them (except for some that might be propelled into the stratosphere from hurricanes) precipitate out long before reaching high altitudes where they can destroy ozone. Even if some of them enter the stratosphere, the chlorine they release remains at a constant "background" level. It certainly doesn't increase annually, as has been happening in recent years.
Thus, while Robinson and other skeptics are wrong when they suggest that vast amounts of these unstable natural chlorinated compounds are getting up into the stratosphere, a great portion of our CFCs does get there -- as the balloon and satellite measurements prove.
So where did the skeptical argument about "natural sources" originate?
In my research, I found out early on that the source of these claims was a very nice, sincere fellow named Rogelio Maduro. Roger is not an atmospheric physicist or chemist; but he is, regrettably, a follower of Lyndon LaRouche, and a regular contributor to LaRouchie publications such as 21st Century Science and Technology and the Executive Intelligence Review. Alas, his co-authored book, The Holes in the Ozone Scare, published by the LaRouchie press, was the first and, to my knowledge, the only skeptical book on the ozone controversy to have appeared. It was unfortunately the main source of many of the claims later made by Dixy Lee Ray in her book, Trashing the Planet; and the claims were further exaggerated and warped by Rush Limbaugh in his own books and broadcasts.
For example, loosely interpreting a geologist's paper on volcanoes, Maduro suggested that volcanoes typically propel vast amounts of chlorine into the stratosphere, in amounts that dwarf anything man could produce. The paper, in fact, had pointed to the example of a cataclysmic eruption which occurred thousands of years ago; but Maduro cited the example as if modern eruptions were typically of a similar scale.
Of course, modern volcanoes have not been nearly as explosive, nor have they expelled similar amounts of chlorine. Nonetheless, Ray, citing Maduro, misread his footnote and declared that the volcano in question was Mount St. Augustine in Alaska in 1976! That eruption, she mistakenly claimed, released "570 times the total world production of chlorine and fluorocarbon compounds in the year 1975" (Trashing the Planet, p. 45). Limbaugh, in turn citing (and further misreading) Ray's erroneous claim, screwed matters up even more, by identifying the volcano in question as Mt. Pinatubo -- and claiming that this eruption had spewed 570 times more chlorine than our annual production of CFCs!
Thus, an extraordinary cataclysmic event of thousands of years past suddenly becomes a recent eruption -- all to make a totally false point that volcanoes typically expel into the stratosphere amounts of chlorine that dwarf those released by CFCs. It isn't so. Yet Robinson's own argument about the impact of volcanoes appears to be gleaned directly from such unreliable sources.
Sloppy research, relying on secondary, tertiary and dubious sources, only undermines the credibility of the skeptic's case. The above volcano example has already been cited repeatedly and gleefully by "establishment" environmentalists in magazine and newspaper articles counterattacking the skeptics, and portraying them as scientific ignoramuses. In this case, the "establishment" is right.
No, CFCs aren't going to destroy our ozone layer and create any cancer epidemic. But that determination does not rest on the "natural vs. man-made chlorine" argument. That argument is a side show, utterly irrelevant to more basic facts. Yet it is continually advanced by ill-informed skeptics as if it were the most important and convincing "refutation."
There is a related problem here. Robinson and others focus on the economic costs of banning freon and other CFCs, as if these higher costs alone constituted sufficient refutation of the need for such a ban. But if the alternative were indeed a global health crisis, most rational people would rightly conclude that the higher economic costs of replacement chemicals were worth it. Just because CFCs are useful and economic in some contexts doesn't mean that their harm might not outweigh their good.
Clearly, the economic argument rests solely upon the more basic argument over whether CFCs are in fact destroying our ozone layer. If we can convincingly refute the latter claim, then the economic argument acquires force. If not, though, it is irrelevant.
We do not, however, answer that more basic question by making empirically shoddy cases. We cannot assume, by mere deduction, that because man's mind produces goods, that anything he produces is "good." We cannot answer empirical questions by simply deducing or making assumptions from our philosophical and free-market premises.
As Objectivists, we must remember that our first loyalty must be to facts. I, for one, would appeal to those involved in specialized controversies first to do their homework. LOTS of homework -- not just an afternoon or two of reading. That goes for all specialized controversies, by the way -- from ozone, to whether Kant was truly "evil." These are largely empirical questions, and not matters that can be decided solely from an armchair, and primarily by logical inference.
That's the lazy man's way of "thinking." But when thinking, it helps to know some facts, so that we have something to think about. By knowing what we're talking about, we won't embarrass ourselves and, by extension, the public reputation of our shared philosophy.
Marsha Enright raised some very good questions, and Will Wilkinson is on the right course in his answers. I don't want to get into a long and involved series of explanations or debates over scientific questions (I'm no scientist), but since I largely initiated this discussion, I guess I'm obligated to clarify at least the basics.
1. Will is correct in his understanding of how and why "natural" chlorinated compounds get washed out in the lower atmosphere: they are far less stable, and far more soluble, than CFCs. CFCs -- chlorofluorocarbons -- are entirely synthetic, man-made chemicals. Their very advantages (they are very stable -- virtually inert -- and thus do not easily react with other chemicals) cause them to remain intact for many years, mix with the atmosphere very thoroughly, and eventually seep into the stratosphere (the upper atmosphere), where there is an ozone concentration, or "ozone layer." At those altitudes, solar ultraviolet light (UV) is much more potent -- powerful enough to break down even CFCs into their constituent elements (including chlorine).
That, in short, is why CFCs can reach the stratospheric ozone layer in significant quantities, while most naturally occurring chlorine compounds normally can't. And that's why a disproportionate and growing percentage of stratospheric chlorine comes from CFCs, not natural sources.
2. Yes, CFC production has been pretty well quantified, and I've seen papers showing a pretty close linkage between quantities of CFCs produced over the years, and the amounts eventually found in the atmosphere.
CFCs are used not only as spray propellants (they've been banned in the U.S. as propellants for some years, in fact), but also in industrial solvents, in auto headlights (halogen), in refrigerators and in air conditioners (Freon and similar compounds). Their uses had been escalating very rapidly over the past several decades, until recent treaties limited their production.
The problem with CFCs in the stratosphere is that even though the concentrations may be small, one chlorine molecule can destroy thousands of ozone molecules. Once released to roam in the stratosphere, a chlorine monoxide molecule drifts around, reacting over and over with all ozone molecules it contacts, via a complicated series of chemical reactions. (I'm not a chemist, but the equations have been published in major scientific journals I've read.) That's why even relatively small concentrations of CFCs in the atmosphere can have a disproportionately destructive effect on ozone -- if meteorological conditions are right. That brings us to...
3. Marsha is on the right track in her understanding as to why ozone depletion can't and won't become a global threat. The reason: meteorology.
First: why worry about the amount of atmospheric ozone? Because atmospheric ozone blocks out a great deal of damaging solar ultraviolet radiation from reaching the ground. In the absence of ozone, UV would reach us in much greater amounts, possibly causing much more skin cancer, and possibly even damaging crops and wildlife.
Is it possible for ozone levels to steadily decline over time? Probably not.
Ozone (O3) is always being destroyed and created by natural processes. O3 that is broken down by solar UV is also constantly replenished by UV's action in breaking down oxygen. In other words, O3 simply isn't going to steadily decline and vanish. As long as there is oxygen and UV to act on it, Mother Nature will always make more ozone. Other things equal, there's a "natural balance" of ozone creation and destruction. Levels fluctuate wildly over the years, seasons, even days; but like a choppy ocean surface, there's always a natural "sea level" of ozone in the atmosphere.
But some scientists worry that the addition of man-made CFCs into the so-called natural "balance" will throw things out of kilter, causing overall O3 levels to decline. The discovery of the Antarctic "ozone hole" in 1985 fueled that fear. And if CFCs cause eventual ozone depletion over populated areas, an environmental and health nightmare could ensue.
This is theory only, and in my view, pure hokum. Global ozone levels have not been responding in the way the CFC "depletion" theory suggests. To make their case, environmentalists and government scientists have been shamelessly distorting the data -- for example, measuring "declining trends" in ozone by arbitrarily picking out years with unusually high ozone levels, and using those as the "base years" for comparisons. But ozone levels constantly, naturally fluctuate, especially during the 11- year "solar cycle." Not surprisingly, even an average ozone year looks like "depletion" when measured against a peak year in the ozone cycle.
Dr. Linwood Callis of NASA led an agency investigation of the causes of ozone fluctuations during the 1980s. As he told me: "The overwhelming portion of the ozone depletion in the 1980s was due to natural causes," and the effect of CFCs "was really quite small -- less than one-half of one percent." (His paper "Ozone Depletion in the High Latitude Lower Stratosphere: 1979-1990" appeared in the Journal of Geophysical Research, Vol. 96, No. D2, Feb. 20, 1991, pp. 2921-2937.) Callis went on to say that he thought that scientists blaming CFCs for ozone depletion were being "less than honest."
Even so, the bottom line is not CFCs, chlorine, or even ozone levels. From a health and environmental standpoint, the only worry is UV levels. And guess what? The only actual measurements of UV penetrating to the ground show that UV levels have been going DOWN, not up. Scientists link the decline of UV to increasing cloud cover in recent years. Obviously, you can't have a cancer epidemic if UV is declining, rather than increasing. At any rate, reality hasn't exactly been conforming to the theories of the alarmists. (See Joseph Scotto, et al., "Biologically Effective Ultraviolet Radiation: Surface Measurements in the United States, 1974 to 1985," in Science, Vol 239, p. 762.)
Well, what about that Antarctic "ozone hole?" First of all, it isn't a "hole." The "ozone hole" is a temporary, chlorine- enhanced thinning of the O3 layer over Antarctica 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 chlorinated compounds, unmolested by UV, in the (c) "polar 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 chlorine monoxide -- not the CFCs themselves -- then reacts 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, because mountains there break it up. Nor do the stratospheric 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 announce "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 skeptic'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 stratosphere, 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 austral spring (our autumn).
By the way, lest anyone worry about Antarctic penguins: 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 summer. For the same reason that you can't get a suntan at dawn, you get less UV in the spring than the summer. Any animal that can survive the sun during the polar summer, can survive it during the spring "ozone hole."
Given the media's excruciatingly poor and always alarmist coverage of the ozone issue, Marsha and Will are to be commended for grasping the basics so well. I hope this answers at least the basic remaining questions for anyone interested, so that I may now return to earning a living for myself, my family and all my friends at the IRS.