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Europees Commissaris
Geregistreerd: 25 juni 2006
Locatie: Vlaanderen/Jutland
Berichten: 7.098
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Citaat:
Oorspronkelijk geplaatst door Voltian
Euhm...
Rikbe, Willem, ontkennen jullie het bestaan van "het gat in de ozonlaag"?
(gewoon een vraag om uw standpunt hierover te begrijpen, ik ben niet zeker of ik de posts juist interpreteer)
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Absoluut niet. Maar wel de oorzaken ervan, en de hysterie indertijd.
Citaat:
My Adventures in the Ozone Layer
by S. Fred Singer
National Review, June 1989
The 123-nation Conference to Save the Ozone Layer, held in London in March 1989, 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 phase out completely the chlorofluorocarbons (CFCs) and other widely used chemicals. It seems they know better.
It is rumored that Mrs. Thatcher was converted into a global ozone fan by Sir Crispin Tickell, the diplomat turned eco-freak. Lord knows who the President Bush has been listening to, but he deserves better advice.
Now it's on to a European conference in the Hague to which Maggie and George have not been invited --tsk, tsk-- and then a follow- up to London in Helsinki in May. All this after the 1985 Vienna Convention, the Montreal Protocol (Sept 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 hardly spends time in Oslo anymore. My word! When do these people ever govern?
The hyperactivity this creates in the agencies, mainly in 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 for the fact that Congress and its staffs are just as involved. As the Hill folks try to outdo the Administration and the feds dream up new initiatives, things are building up to a fever pitch -- spurred on by lurid stories in the media about the imminent danger. "Arctic Ozone is Poised for a Fall " scream the headlines. "Skin Cancer is on the Rise!"
Is it all hype? Or is it a hoax? And is the hysteria for real? As we'll see later, the scientific basis for the much-touted ozone crisis may be evaporating-- leaving the new breed of geo- eco-politicians high and dry.
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How did we get here? It's a long way from the supersonic transport to the Antarctic "ozone hole". But 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 sonic boom and noise objections didn't bring down the program, the activists discovered the stratospheric ozone layer and the fact that a fleet of 500 planes might have some influence on the ozone content of the upper atmosphere. Most influential was the argument that a reduction in the ozone content would increase the rate of skin cancers. That did it. And the skin cancer scare has been with us ever since, inextricably intertwined with the stratospheric ozone issue.
Throughout these past two decades many truths were uncovered by outstanding and imaginative researchers, but many truths were not revealed to the public -- and quite a few things were propagated that departed from scientific truth. Scientists, by and large, behaved honorably, although egos and ambitions collided with the facts, tempting some to ignore facts. Politicians had no such problems or any hesitation to manipulate science and even scientists. And the media had a field day. Let me give you a personal account of this fascinating history.
SSTs and Ozone
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. Of course, I had some background in atmospheric physics, having been active in the earliest rocket experiments on the ozone layer, and even invented the instrument that later became 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 some time in 1970, as I recall; and then only in the context of the effects of the water vapor from the burning of the SST fuel. It was a year later before we came to realize that the main culprit would be the small component of nitrogen oxides (NOX) created in any combustion process.
The first estimates suggested that some 70% 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 cancelation of the SST project. Of course, the two prototypes --all that was authorized-- wouldn't have caused any noticeable effect; but the SST opponents managed to confuse the issue. England and France went on to build the Concorde -- with no environmental consequences.
Only later was it discovered that there were also natural sources of stratospheric NOX and the SST effect soon fell to 10%. But then laboratory measurements yielded better data for the theory, 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 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 with respect to theoretical predictions -- particularly of atmospheric phenomena.
It's a matter of some irony that current theory predicts that aircraft exhausts counteract the ozone-destroying effects of CFCs! But remember: it's theory, and it could change.
Science is supposed 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?
Methane and CFCs
Once Pandora's box had been opened, we all began to look for other ways to affect stratospheric ozone. During my SST tenure I became intrigued by the idea that human-produced (or at least, human-related) methane could affect the stratosphere. Methane is a long-lived gas in the atmosphere, very difficult to destroy. It was thought to be mainly due to natural sources, swamps and things like that. But after thinking about it I found that many important sources are related to human activities: rice paddies, cattle, 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, affecting the local chemistry, and eventually adding to the water vapor in the dry stratosphere. To my surprise I found that the methane contribution to water vapor is about as large as that from the hypothetical SST fleet. So never mind the SSTs; mankind is already messing up the stratosphere and has been doing it for a long time.
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 uphold my scientific reputation. It was finally published in 1971 in the British journal Nature. But no one got excited about it: stopping cows from belching and other gaseous exhalations didn't ignite the environmental community. Cows are so-- natural and low-tech. Not a great cause. And besides -- controlling their emissions could be messy.
CFCs are different. Brilliant scientific work by Britisher James Lovelock, who developed the methods to measure tiny amounts of CFCs in the atmosphere, and the calculations of 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 environmentalists' reaction was ecstatic. At last, an industrial chemical-- and produced by big bad DuPont and their ilk. What a cause! What a worthy successor to the SST, now that the 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 Western nations 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 -- and 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 any 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 a 18% ozone decrease, based on a certain standard CFC scenario. By 1982 the effect had decreased to 7%, by 1984 to 2-4%. 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".
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% 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 was a smashing success with the anti-CFC crowd and put new life into them. Dropping their earlier opposition the industry rolled over and played dead, and finally joined the environmental activists. It may have dawned on them 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. In the government, the strong push came from EPA and State, where mid-level bureaucrats fashioned a steamroller that pushed the White House to propose, as a compromise, a CFC production freeze, followed by a rollback to 50%. That was the upshot of the 1987 Montreal Protocol, carefully prepared by the Vienna Convention and many other international meetings.
But some things didn't quite fit. I was puzzled by the sudden onset of the AOH in 1975. It suggested some kind of a trigger, unlikely to come from the steady increase of CFC content of the atmosphere. What could it be? A climate fluctuation that cooled the stratosphere enough so that the ice crystals would form? But if a 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 Nov 1988, I finally published a short note in Eos , the house journal of the American Geophysical Union, the major professional society in this field.
The Skin Cancer Issue
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 the hole had grown, since 1975, malignant melanoma had increased nearly 100% -- 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 U.S.
In any case, melanomas have not been related directly to increased UV exposure.
And finally, melanoma rates have been increasing by about 800% 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 less today than in 1974. The causes of melanoma must include more than UV.
There does exist a correlation between UV-B intensity and benign 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 the northern U.S. and south Texas. But we should not assume that all the increase is just due to UV intensities. Life styles in warmer climates are conducive to greater and longer exposures and may therefore contribute as much or more to skin tumors than the UV values themselves.
One other fact they don't much talk about: Since ozone content decreases strongly in moving towards the equator, a 5% 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 60 miles south, the distance from New York to Trenton or from Palm Beach to Miami. An increase in altitude of 1000 feet would produce the same result.
Global Ozone Trends
The latest phase in the war against the CFCs came in March 1988 when the NASA Ozone Trends Panel announced its findings, after a massive re-analysis of data from ground stations and satellites. After subtracting all the natural variations they could think of -- some of them as large as 50% within a few months at a given station -- they extracted a statistical decrease of 0.2% 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 steady change.
Furthermore, there is the matter of choosing the time period of study, its beginning and end. When people ask me whether the climate is getting warmer or colder, I generally just answer "yes". It all depends 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 1« 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 their analysis. One thing stands out from their announcement: the trend found is greater than calculated from the theory. Now this could mean that the theory is wrong, or the trend they found, or both. But the Panel's conclusion was different: the trend is "worse than expected", and therefore CFCs must be phased out completely and more 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 with it?
The Politics of Ozone
It's not difficult to understand some of the motivations. For scientists: recognition for keeping dusty records or running complicated computer models that are rather dull; 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 treaty 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 to the last. There are well- intentioned individuals who are sincerely concerned about what they perceive as a critical danger to the health of future generations. Many of the professionals share the same incentives as government bureaucrats: status, salaries, perks and power. And then there are probably those with hidden agenda of their own -- not just to "save the environment" but to change our economic system. The telltale signs are the attack on free enterprise, the corporation, the profit motive, the new technologies. Some are socialists, some are Luddites.
Most of these "compulsive utopians" have a great desire to regulate -- on as large a scale as possible. To them global regulation is the " holy grail". That's what makes the CFC-ozone issue so attractive to them. And it showed tellingly at the Hague conference in March 1989 -- the one the U.S. was not invited to. You can see why. These world environmental leaders actually proposed a new U.N. agency, aptly named "Globe". Globe was supposed to invoke and enforce sanctions on nations that didn't buckle 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 ... carbon dioxide and a dozen other trace gases". So that's what they are headed for. Doniger fairly chortles when he recounts how "hardliners" and "antiregulatory elements" in the White House fought a losing battle against tough control of CFCs because they "seemed either to disbelieve the scientific evidence of ozone depletion or to belittle its consequences."
The CFC-Ozone Theory Revisited
As one of those hardliners I need to explain where I stand and why I am unrepentant in considering extreme controls on CFCs as 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 only "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 the NAS results have varied all over the place, predicting 18% ozone depletion in their 1979 report, 7% in 1982, and 2 to 4% in 1984. To make matters worse for Doniger's case, evidence is firming up that volcanoes, and perhaps salt spray from the oceans, contribute substantially to stratospheric pollution, and thus dilute the effects of CFCs.
New scientific results, from the laboratory and stratosphere, are pouring in constantly; the theory has been in a state of flux and is bound to change. A major advance, just during the past year, was the recognition that "heterogenous" reactions on stratospheric ice particles play a dominant role in the ozone destruction process; but we don't yet know the crucial reaction rates or even some of the basic scientific facts.
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 roll-back, he argues for a complete phase-out of CFCs -- without waiting for better scientific data.
The Antarctic Ozone Hole (AOH) Revisited
The standard CFC-ozone theory did not predict the ozone hole, the temporary thinning of the stratospheric ozone layer in the Antarctic; nor can it account for its future course. The prevailing view is that the AOH first arose, quite unexpectedly, in 1975 and grew rapidly thereafter, as a direct result of the increasing release of CFCs into the atmosphere. According to recent reports, the same phenomenon is just about to happen 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, 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. Furthermore, any reasonable changes in CFC concentration should not have much impact-- as long as there was some minimum level of stratospheric chlorine, derived from any of the many natural and manmade sources.
In reaction to my suggestion published in Eos, Professor Marcel Nicolet, a distinguished Belgian atmospheric physicist, has now 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%] 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 most interesting difference from other parts of the world."
This remarkable quote clearly indicates that meteorological factors influence, and may even control, what happens to ozone in tha Antarctic. The AOH may now wax and wane; it may even disappear and re-appear regardless of the actual level of CFCs in the atmosphere. The theory is not yet able to predict the future course of the AOH and interesting scientific questions remain.
The Global Ozone Decrease Revisited
As noted earlier, the Ozone Trends Panel (OTP) of NASA announced the existence of a declining global ozone trend in March 1988, accompanied by a press release and executive summary; the full report giving the underlying analysis has not yet been released for general review. Yet much political action has already been initiated on the basis of the announcement. For example, Western nations, principally the U.K., are pushing to tighten the Montreal Protocol by completely phasing out most CFCs, the alleged cause of the ozone decline, instead of just freezing and gradually rolling back CFC production to 50% as agreed to in the Protocol.
While the OTP Report itself is not available, a parallel report from the Center for Applied Mathematics of Allied-Signal, 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 1« solar cycles and includes two solar flux decreases vs. only one increase, i.e. two decreasing ozone trends and one period of 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 that are increasingly penetrating the lower stratosphere. But current theory does not envisage ozone destruction from this source.
Natural effects related to solar cycles may be responsible for an observed ozone decline. For example, the decline in strength of the solar cycle after 1958 could lead to an ozone decline.
This last observation leads to an interesting aside. Solar cycles have varied greatly. In recent times, sunspot numbers have been as low as 40 (in 1817) and as high as 190 (in 1958) at the peak of the cycle. 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.
What to Do?
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 is ephemeral; it comes and goes, and seems to be controlled by climatic factors outside of human control rather than by CFCs. The reported decline in global ozone may 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 melanoma has been going for at least 50 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 efforts, the negotiations, the Protocol, and all the international conferences is pretty shaky -- to say the least. How poignant! Now may be the time to reflect on the decisive words of immortal Comrade Lenin: "Shto dyelat'-- What to do?"
The regulatory regime for CFCs adopted in the Montreal Protocol is immensely complicated. Enforcing it on a worldwide basis will be a nightmare and involve the use of trade barriers and sanctions confined 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 large. Recent newspaper accounts have 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 shares and profits reflected in Doniger's choice of words. When DuPont was fighting the Protocol, they were said to be concerned about "price" [read: profits]; but once they decided to manufacture substitutes, Doniger had them concerned about the "right market incentives". An interesting and contentious question: should DuPont and other chemical manufacturers keep the profits that will be created as a result of governmental regulation?
And substituting 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 replacement. Nor is this all; about $135 billion of equipment use CFCs in the 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 100 million home refrigerators, the air-conditioners in 90 million cars, and the central air-conditioning plants in 100,000 large buildings. Good luck! The total costs haven't really been added up yet.
These are some of the costs we are now trying to impose on the developing countries who can ill afford them. Sanctions through a new U.N. 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. One can hear already the charge of environmental imperialism from third-world countries accusing the West of protecting its pocket books 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 the Asians might just go along. So it's environmental blackmail vs. environmental imperialism. Choosing up sides could prove difficult for some. I'll sit this one out and wait for better and more complete science.
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 societies 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 on the availability of safe substitutes. He should have added careful science as another condition.
http://www.sepp.org/key%20issues/ozone/advinozon.html
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Zonder O2, geen dierlijk leven. Zonder CO2, geen leven.
"The reason people use a crucifix against vampires is that vampires are allergic to bullshit." - Richard Pryor
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28 juni 2009, 13:21
