My adventures in the ozone layer.

And the Chicken Littles in Washington, Oslo, and the Hague

have all the answers, oblivious to the scientific evidence

that shifts month by month.

MRS. THATCHER'S 123-nation Conference to Save the Ozone Layer, held in London this March, ended with a whimper. The developing nations, principally China and India, were quite unconvinced by the evidence and unwilling to go along with the European Community and the United States in rushing to completely phase out chlorofluorocarbons (CFCs) and other widely used chemicals. The developing nations have a point.

The London conference has been followed in the last three months by gatherings in the Hague and in Helsinki. All this after the 1985 Vienna Convention, the Montreal Protocol (September 1987), Geneva, Toronto, and who knows how many other international gabfests in between. Who can keep track of them? Norway's Prime Minister, Mrs. Gro Harlem Brundtland, a devout environmentalist, hardly spends time in Oslo any more. When do these people ever govern?

The hyperactivity this creates in U.S. government agencies, mainly the State Department and EPA, has to be seen to be believed. The congressional Government Accounting Office would have done an investigation and totaled up the thousands of hours and the huge resources spent on this issue-except that Congress and its staffs are just as involved. Things are building up to a fever pitch-spurred on by lurid stories in the media. "Arctic Ozone Is Poised for a Fall," scream the headlines. "Skin Cancer Is on the Rise!" Is it all hype? Or are there real grounds for worry? As we'll see, the scientific basis for the much-touted ozone crisis may be evaporating-leaving the new breed of geoeco-politicians high and dry.

IT ALL STARTED with the SST, just twenty years ago. The emerging environmental movement scored its first great victory by convincing Congress to cancel the program to build two SST prototypes that would have been tested in the stratosphere. When objections concerning noise and sonic booms didn't bring down the program, the activists discovered the stratospheric ozone layer and the fact that a fleet of five hundred planes might have some effect on the ozone content of the upper atmosphere. Most influential was the argument that a reduction in ozone would allow more solar ultraviolet (UV) radiation to reach the earth's surface, and thus increase the rate of skin cancers. That did it: the skin-cancer scare has been with us ever since, inextricably intertwined with the stratosphericozone issue.

Throughout these past two decades many truths have been uncovered by imaginative researchers, but many of these have not been revealed to the public-and quite a few things have been propagated that departed from scientific truth. Scientists, by and large, behaved honorably, although egos and ambitions sometimes collided with facts, leading to a temptation to ignore the facts. Politicians had no hesitation in manipulating science. And the media had a field day. Let me give you a personal account of this convoluted history.

I FIRST GOT INVOLVED in the SST issue in 1970 while serving as a deputy assistant administrator of the EPA. I was asked to take on the additional task of chairing an interagency committee for the Department of Transportation on the environmental effects of the SST. (I had some background in atmospheric physics, having been active in the earliest rocket experiments on the ozone layer, and I even invented the instrument that later become the main ozone meter for satellites.) There were many false starts. We knew so little about the upper atmosphere. The ozone problem didn't come up until sometime in 1970, as I recall; and then only in the context of the effects of the water vapor from the burning of the SSTs' fuel. It was a year later before we came to realize that the main culprit would be, not H[sub.2]O, but the small amount of nitrogen oxides (NOX) created in any combustion process.

The first estimates suggested that some 70 per cent of the ozone would be destroyed by an SST fleet; without the ozone shield"lethal" ultraviolet radiation would stream down to sea level, and an epidemic of skin cancers would sweep the world. This scare campaign led to the cancellation of the SST project. Of course, the two prototypesall that was authorized-wouldn't have caused any noticeable effect; but the SST opponents had succeeded in confusing the issue. England and France went on to build the Concorde-with no apparent environmental consequences.

Only later was it discovered that there were also natural sources of stratospheric NOX, and the SST effect soon fell to 10 per cent. But then laboratory measurements yielded better data, and by 1978 the effect had actually turned positive: SSTs would add to the ozone! It became slightly negative again after 1980, but by then the SST had been forgotten and all attention was concentrated on the effects of CFCs.

Few outside my special field know about these wild gyrations in the theoretical predictions. But those of us who lived through them have developed a certain humility and affection toward the ozone layer. It's a matter of some irony that current theory predicts that aircraft exhaust counteracts the ozone-destroying effects of CFCs. But remember: it's only a theory, and it could change.

Science is supposed to be value-free. I learned differently when I conducted a modest survey among my colleagues during the SST controversy, I found that those who opposed SSTs for economic (or less valid) reasons also tended to believe that the environmental effects would be serious. Those who liked the idea of supersonic transportation tended to belittle the ozone effects; they turned out to be right a few years later, but how did they know?

ONCE PANDORA'S BOX had been opened, we all began to look for other ways to affect stratospheric ozone. During my EPA tenure I became intrigued by the idea that human-produced (or, at least, human-related) methane could affect the stratosphere. Methane is a longlived gas in the atmosphere, very difficult to destroy. It was thought to be mainly due to natural sources, swampsand things like that. But I soon realized that many important sources are related to human activities: rice paddies, cattle, and oil and gas wells, for example.

I reached two conclusions: that about half the methane input is anthropogenic and should therefore increase as population and GNP grow; and that methane can percolate up into the stratosphere, there to be attacked by solar UV radiation, eventually adding to the water vapor in the dry stratosphere. To my surprise I found that methane's contribution to water vapor is about as large as that feared to come from a hypothetical SST fleet.

Public interest in my methane theory was mild, to say the least. The American journal Science turned it down, based on the recommendation of the reviewer-a good friend, who then called to tell me he did it to protect my scientific reputation! It was finally publishcd in 1971 in the British journal Nature. But no one got excited about it: stopping cows from belching and emitting other gaseous exhalations didn't ignite the environmental community. Cows are sonatural and low-tech. Not a great cause. And besides, controlling their emissions could be messy.

CFCs are different. Brilliant work by a British scientist, James Lovelock, and the calculations of two Californians, Mario Molina and Sherwood Rowland, demonstrated in 1974 the possibility that long-lived and normally quite inactive CFCs would percolate up into the stratosphere, and there be decomposed and attack ozone.

The ecofreaks were ecstatic. At last, an industrial chemical-and produced by big bad Du Pont and others of that ilk. What a worthy successor to the SST, now that that issue was dead.

Regulation was not long in coming. By 1975, voluntary restraints were adopted on the use of CFCs in spray cans, an important but noncritical application. By 1978, the United States and some other Western nations had unilaterally banned CFC use in all aerosol applications.

But that was all for a while. The other applications of CFCs didn't have easy replacements. Substitutes hadn't been developed; and they might turn out to be hazardous, toxic, or expensive-perhaps all of the above. Besides, replacing refrigerators, air conditioners, plastic-foam blowers, and electronic cleaning equipment loomed as an expensive undertaking. Most Europeans and the Japanese were not interested in joining any global agreement, and further unilateral action by the U.S. wouldn't have been very effective globally.

On top of all this, the data from the labs and computers were reducing the threat. A National Academy of Sciences study in 1980 predicted an 18 per cent ozone decrease, based on a certain standard CFC scenario. By 1982 the effect had decreased to 7 per cent, and by 1984 to between 2 and 4 per cent. Ironically, much of the reduction was due to the discovery of the counteracting effects of other pollutants: methane, nitrogen oxides, and carbon dioxide. So-putting these polluting gases into the atmosphere hastens the arrival of global warming by the greenhouse effect while reducing the destruction of ozone.

Then along came the Antarctic "ozone hole" (AOH).

IN 1985, a British group operating an ozone observing station at Halley Bay, Antarctica, published a result that came out of the blue. Beginning around 1975, every October, they observed a short-lived decline in the amount of stratospheric ozone. The amplitude of the decrease had grown steadily, reaching nearly 50 per cent of the total ozone. The finding was quickly confirmed by satellite instruments, which also indicated that the phenomenon covered a large geographic region.

The "smoking gun" had been found-so it seemed. CFCs were immediately suspected; and indeed, chlorine compounds were observed in the region of ozone destruction.

The process itself was a new one and had not been studied before; it involved the presence of ice clouds that formed in the polar winter in the coldest region of the earth's atmosphere. The growth of the hole was "obviously" connected to the rise in the atmospheric CFC concentration; and it seemed only a matter of time before the hole would expand and "swallow us all"-or at least all the world's ozone.

The AOH put new life into the anti-CFC crowd. Dropping their earlier opposition, the industry rolled over and played dead, finally joining the environmental activists. It may have dawned on businessmen that with demand rising and supply limited or even declining, prices and profits could grow nicely. Those with safe substitutes might even gain market share and keep out competitors. Within the government, the strong push came from EPA and State, where midlevel bureaucrats fashioned a steamroller that pushed the White House to propose, as a compromise, a CFC production freeze, followed by a rollback to 50 per cent. That was the upshot of the 1987 Montreal Protocol.

But some things didn't quite fit. I was puzzled by the sudden onset of the AOH in 1975. It suggested some kind of trigger, unlikely to come ftom the steady increase of the atmospheric CFC content. What could it be? A climate fluctuation that cooled the stratosphere enough for the ice crystals to form? But if the cause was a cooling fluctuation, then the hole could disappear if the fluctuation went the other way. Or-the AOH might have existed before. I sent a letter to the editor of Science suggesting this-no luck. So, in November 1988, I finally published a short note in Eos, the house journal of the American Geophysical Union, the major professional society in this field.

MEANWHILE, the hype was deafening. I remember one congressional hearing in 1987-there were so many -where the witness was a noted dermatologist. He explained that since 1975, malignant melanoma had increased nearly 100 per cent-a frightening but true statistic. He simply did not explain three other facts to the Congress or to the media:

-An Antarctic hole should have no effect whatsoever on cancer rates in the United States.

-In any case, melanomas have not been related directly to increased UV exposure.

-And finally, melanoma rates have been increasing by about 800 per cent since statistics were first collected in 1935. There has been no corresponding change in the ozone layer or in the UV reaching sea level. To the contrary, measurements of UV-B (the biologically active component) have shown a pronounced and steady decline at every location; UV intensities in American cities are lower today than in 1974. The causes of melanoma must include more than UV exposure.

There does exist a correlation between UV-B intensity and benign, non-melanoma skin tumors. Their frequency clearly increases as one approaches the equator, where the sun and the UV are both stronger, with tumor incidence more than doubling between Minnesota and south Texas. But we should not assume that all the increase is due to higher UV intensities. Lifestyles in warmer climates are conducive to longer exposures and may therefore contribute at least as much to skin tumors as the UV values themselves.

One other fact they don't much talk about: a 5 per cent decrease in the ozone layer, as calculated by some of the more pessimistic scenarios, would increase UV exposure to the same extent as moving about sixty miles south, the distance from Palm Beach to Miami, or from Seattle to Tacoma. An increase in altitude of one thousand feet would produce the same result.

THE LATEST PHASE in the war against CFCs began in March 1988 when the NASA Ozone Trends Panel (OTP) announced its findings, after a massive reanalysis of data from ground stations and satellites. After subtracting all the natural variations they could think ofsome of them as large as 50 per cent within a few months, at a given station-they extracted a statistical decrease of 0.2 per cent per year over the last 17 years. Making these corrections is very difficult and very technical and very uncertain-especially when the natural variations are a hundred times larger than the alleged steady change.

Furthermore, there is the matter of choosing the time period of study. When people ask me whether the climate is getting warmer or colder, I generally just answer "yes." It all depends on over what time scale we average. If the time scale is a few months, then the answer in the spring would of course be "warmer" and in the fall "colder." Now, 17 years is only one and a half solar cycles; and solar cycles have a very strong influence on ozone content. Another letter to Science-not accepted.

The Panel announced its result with great fanfare, an "executive summary," and a press conference-but no publication (as yet) that would allow an independent check of its analysis. One item stands out from its announcement: the trend found is greater than calculated from the theory. Now this could mean that the theory is wrong, or the trend is spurious, or both. But the Panel's conclusion was different: the trend is "worse than expected," and therefore CFCs must be phased out completely and quickly. The logic of this conclusion escapes me; but this has now become the U.S. position. Can you blame the Chinese and Indians for not going along?

IT'S NOT DIFFICULT to understand some of the motivations behind the drive to regulate CFCs out of existence. For scientists: prestige, more grants for research, press conferences, and newspaper stories. Also the feeling that maybe they are saving the world for future generations. For bureaucrats the rewards are obvious. For diplomats there are negotiations, initialing of agreements, and-the ultimate-ratification of treaties. It doesn't really much matter what the treat is about, but it helps if it supports "good things." For all involved there is of course travel to pleasant places, good hotels, international fellowship, and more. It's certainly not a zero-sum game.

I have left environmental activists till last, There are well-intentioned individuals who are sincerely concerned about what they perceive as a critical danger to humanity. But many of the professionals share the same incentives as government bureaucrats: status, salaries, perks, and power. And then there are probably those with hidden agendas of their own-not just, to "save the environment" but to change our economic system. The telltale signs are the attack on the corporation, the profit motive, and the new technologies.

Some of these "coercive utopians" are socialists, some are technology-hating Luddites; most have a great desire to regulate-on as large a scale as possible. That's what makes the CFC/ozone issue so attractive to them. And it showed tellingly at the Hague conference this March-to which the U.S. was not invited. You can perhaps guess why. These geo-eco-politicians actually proposed a new UN agency, aptly named "Globe." Globe was supposed to invoke and enforce sanctions on nations that did not knuckle under to the environmental dictates of those who knew better. wow!

Globe didn't fly-this time round. Here is David Doniger, senior attorney for the activist Natural Resources Defense Council, writing in the National Academy's Issues in Science and Technology in 1988: "[The CFC protocol] serves as a precedent for . . . [protocols on] carbon dioxide and a dozen other trace gases." So that's what they are headed for. Doniger fairly chortles when he recounts how "hard-liners" and "anti-regulatory elements" in the White House fought a losing battle against tough control on CFCs because they "seemed either to disbelieve the scientific evidence of ozone depletion or to belittle its consequences."

As one of those hard-liners, I need to explain where I stand and why I am unrepentant in considering any extreme controls on CFCs to be premature. I tried to explain all this in a letter to the editor of Issues, but he turned it down. Twice, in fact. So much for open discussion of important scientific and public-policy issues.

I am not against CFC control at all; but look at the poor state of the scientific evidence. The case against CFCs is based on a theory of ozone depletion, plausible but quite incomplete-and certainly not reliable in its quantitative predictions. Doniger himself does a good job of undermining the credibility of the theory-his onl "witness for the prosecution." In his own words:

-"Current models for predicting ozone depletion are inadequate."

-"A National Academy of Sciences [NAS] report . . . quickly became outdated because of new scientific information."

He neglects to inform us that during the past decade the NAS results have varied all over the place. To make matters worse for Doniger's case, evidence is firming up that volcanoes, and perhaps salt spray and bio-chemical emissions from the oceans, contribute substantially to stratospheric chlorine, and thus dilute the effects of CFCs. And new scientific results, from the laboratory and the stratosphere, are pouring in constantly; the theory has been in a state of flux and is bound to change.

Having impugned the CFC/ozone theory-the only basis for making predictions-Doniger nevertheless insists on immediate draconian measures to control CFC production. Not content with a temporary freeze or a rollback, he argues for a complete phase-out of CFCs-without waiting for better scientific data.

THE STANDARD CFC/ozone theory did not predict the ozone hole, nor can it account for its future course. According to recent reports, an ozone hole is just about to open in the Arctic-and, by implication, all over the globe. That's a scary thought-and it has made a great impact on the public as well as on governments. It probably was the main impetus for the Montreal Protocol.

This sudden growth of the AOH may, however, as I mentioned before, simply signal the presence of a triggering mechanism that has nothing to do with the steady increase in CFC concentration. Under this hypothesis, the AOH would not continue to grow as CFCs build up, and could even be ephemeral.

In reaction to my suggestion published in Eos, Professor Marcel Nicolet, a distinguished Belgian atmospheric physicist, has reminded us in a note to the same journal of a long-forgotten publication by G. M. B. Dobson, the Oxford professor who started modern ozone observations. Dobson recounts that when the Halley Bay Antarctic station was first set up in 1956, the monthly telegrams showed that "the values in September and October 1956 were about 150 [Dobson] units [50 per cent] lower than expected. . . . In November the ozone values suddenly jumped up to those expected . . . It was not until a year later, when the same type of annual variation was repeated, that we realized that the early results were indeed correct and that Halley Bay showed a most interesting difference from other parts of the world."

AS NOTED EARLIER, the Ozone Trends Panel of NASA has not yet released its full report for general review. Yet much political action has already been initiated on the basis just of the announcement. For example, Western nations, principally the UK, are pushing to tighten the Montreal Protocol by completely phasing out most CFCs, instead of just freezing and gradually rolling back CFC production to 50 percent as agreed to in the protocol.

While the OTP report itself is not available, a parallel report from the Center for Applied Mathematics of AlliedSignal, Inc., was distributed at a UN Ozone Science Meeting at the Hague in October 1988. The Allied study deals with many of the corrections necessary to establish a believable trend. The estimated change in total ozone over the 17 years 1970-86 is somewhat less than the OTP result. But the change shows a surprisingly strong dependence on the choice of time period. A simple explanation may be that the 1970-86 period covers only one and a half solar cycles and includes two solar flux decreases versus only one increase, i.e., two periods of decreasing ozone trends and one increase. Thus the reported global ozone decline may just be an artifact of the analysis procedure.

On the other hand, if the ozone trend is real, then there are several possible explanations:

-CFCs are indeed lowering the average concentration.

-Human-related factors other than CFCs are decreasing ozone levels. One such factor could be methane, as mentioned earlier. Another could be commercial jet aircraft, which are increasingly penetrating the lower stratosphere. But current theory does not envision ozone destruction from this source.

-Natural effects related to solar-cycle variability may be responsible for an observed ozone decline. For example, the decline in strength of the solar cycle after 1958 could account for an ozone decline. This hypothesis leads to an interesting aside. Solar cycles have varied greatly. In recent times, sunspot numbers at the peak of the cycle have been as low as 40 (in 1817) and as high as 190 (in 1958). During the Maunder Minimum (1645-1715) sunspots were essentially absent. This suggests that there could have been substantial changes in average ozone levels in the past, approximating those feared to result from the release of CFCs. It would be interesting, therefore, to search the historical records for any biological consequences to humans, agricultural crops, or marine life caused by low ozone levels around 1700.

THE CURRENT SITUATION can fairly be summarized as follows: The CFC/ozone theory is quite incomplete and cannot as yet be relied on to make predictions.

The natural sources of stratospheric ozone have not yet been delineated, theoretically or experimentally. The Antarctic ozone hole may be ephemeral; it may be controlled by climatic factors rather than by CFCs. The reported decline in global ozone may just be an artifact of the analysis. Even if real, its cause may be related to the declining strength of solar activity rather than to CFCs. The steady increase in malignant melanomas has been going on for at least fifty years and has nothing to do with ozone or CFCs. And the incidence of ordinary skin tumors has been greatly overstated.

So-the basis for all of the control efforts, the negotiations, the protocol, and the international conferences is pretty shaky. Now may be the time to reflect on the decisive words of the immortal Comrade Lenin: "Shio dye/at'?-What to do?"

The regulatory regime for CFCs adopted in the Montreal Protocol is immensely complicated. Enforcing it will be a nightmare, involving the use of trade barriers and sanctions applied not only to CFCs but to products manufactured with CFCs-such items as foam plastics and electronic circuit boards that go into computers and TV sets. It will prove to be a contentious issue, particularly since special concessions were given to Third World nations and the USSR. The Common Market operates under a European production cap, which further complicates the situation.

The stakes involved are high. Recent newspaper accounts have the EPA predicting a six-fold increase in price, as growing demand for CFCs presses against a limited supply. You can see the struggle for market share and profits reflected in Doniger's choice of words. When Du Pont was fighting the protocol, it was said to be concerned about "price" (read: profits); but once it decided to manufacture substitutes, he talked only about the "right market incentives." An interesting and contentious question: Should Du Pont and other chemical manufacturers keep the profits that will be created as a result of government regulation?

And finding substitutes for CFCs is no simple matter. A New York Times report of March 7, 1989, talks about the disadvantages of the CFC substitutes. They may be toxic, flammable, and corrosive; and they certainly won't work as well. They'll reduce the energy efficiency of appliances such as refrigerators, and they'll deteriorate, requiring frequent replenishment. Nor is this all. About $135 billion worth of equipment uses CFCs in tbe U.S. alone, and much of this equipment will have to be replaced or modified to work well with the CFC substitutes. Eventually, that will involve one hundred million home refrigerators, the air conditioners in ninety million cars, and the central air-conditioning plants in 100,000 large buildings. Good luck!

These are some of the costs we are now trying to impose on developing countries, which can ill afford them. Sanctions through a new UN agency seem to be out-at least for the time being. But trade barriers can accomplish the same results and won't make us beloved. Third World countries are already heard accusing the West of protecting its pocketbooks as well as its fair skins. (Keep in mind that olive-skinned and dark-skinned people are not very susceptible to skin tumors caused by solar ultraviolet rays.)

Of course, if we in the West should be inclined to pay the bill for this major industrial perestroika, then others might just go along. So it's environmental blackmail versus environmental imperialism.

Governments have yet to address what I regard as the real policy issue: how to make decisions about controls on CFC production, and the timing of these controls, in the light of incomplete and often conflicting scientific information. What is needed, it seems to me, is a more complete analysis that weighs the risks to society stemming from a delay in instituting production controls against the possibility of substantially improving both observations and the theory so that predictions can be relied upon. At least, when George Bush decided to go along with born-again environmentalist Maggie Thatcher, he qualified his support for a complete CFC phase-out depending on the availability of safe substitutes. He should have added careful science as another condition.