The Ozone Backlash-Doomsday Predictions

Dr. Sarfaraz K Niazi (e-mail: niazi@niazi.com)

Nature has its ruthless ways of conducting the business of life. A system infinitely intricate yet delicately balanced makes life possible on planet Earth. The ozone layer in the stratosphere (15-30 kilometer above the earth's surface, the distance to which passenger balloons can manage to reach) is a classic example. The fury of sun creates, among many other things, intense outburst of ultraviolet radiation, the type of radiation extremely harmful to human life. The ozone layer conveniently filters out the ultraviolet spectrum of the radiation; letting illumination in but deflecting back the ultraviolet spectrum. Ozone, a form of oxygen, also keeps us warm by blocking the heat from deflecting back to atmosphere. (Ozone is made up of two atoms of oxygen; oxygen gas in atmosphere is made up of two atoms of oxygen).

Man, in his current posture, dating back to only about 10,000 years, appears ardently and infinitely capable of interfering with the plans of Nature. (Philosophic argument: Did Nature plan man to be able to interfere and to bring his own destruction?). One such interference came from man's ability to cook up new chemicals. Chemicals like chlorofluorocarbons (CFCs) used in the refrigeration and more commonly in aerosol spray cans. CFCs are small synthetic molecules (containing carbon, chlorine and fluorine) which are quite inert and vaporize intensely making them ideal compounds for refrigeration and air conditioning where they are repeatedly compressed and decompressed to produce cooling effect. In aerosol spray cans, when the release button is actuated, CFCs present in the liquid form vaporize instantly and burst out carrying with them the contents such as hair setters, perfumes, mosquito repellents, anesthetic drugs, deodorants, etc. The discovery of these CFCs had given a great boost to the refrigeration and aerosol industry.

Like many other serendipitous discoveries, a connection was reported in 1973 between the use of CFCs and the integrity of the ozone layer. It was postulated by the University of California chemists Sherwood Rowland and Mario Molina that these apparently inert molecules somehow float their way into stratosphere where they break down into chlorine which chemically reacts with the ozone. The net effect being a gradual thinning out of the ultraviolet cover on the globe. The theory held very well with the discovery that indeed the ozone hole that appears in the Antarctic is widening. Ecologists worldwide took notice of it and thus began one of the most successful environmental battle--to ban CFCs. The Montreal Protocol signed by the industrialized nations mandated removal of all CFCs in use. So strong had been reaction to this threat to mankind that the United States abandoned development of supersonic transporters (the SSTs) for reasons which included the possibility of these planes spewing out chemicals that might react with the ozone layer. Concords when flying in the US territory must fly subsonic and at lower altitude.

So far this reads like a classic story of man's success in reclaiming environment; but wait, there is yet a melodramatic ending to this story. After the CFC hazard was established, the task of monitoring the extent of damage to environment was relegated to several agencies in the United States including the NASA (National Aeronautics and Space Administration). Like many other government agencies, NASA funding has continuously been under the axe of the US Congress. And like many other agencies and government programs that strive first to perpetuate themselves at any cost, NASA continued the publicity above ozone alive. And that caused a tumultuous uproar in the scientific and lay press to discard the ozone depletion theory. The crisis began on February 3, 1992 when NASA called a hasty press conference to declare its preliminary research findings that the early estimates of yearly losses of ozone layer were grossly underestimated and that the loss of ozone cover is not limited to the remote Antarctic but it is now over the very populated regions. Al Gore, the then Senator made his memorable speech in the Congress and the White House pushed for speedier removal of CFCs from environment. In April 1992 NASA reported their final research findings but now it turned out that the preliminary conclusions did not pan out because of sudden warming in the Arctic reducing ozone depletion. Another study revealed that despite claimed depletion of the ozone layer, the ultraviolet levels on land at different locations have barely changed. This caused many scientists and the public press to start questioning the intentions of NASA since the earlier press conference could have waited till the final results were in. But then the NASA was supposed to get a renewal of their funding in February and the press conference conveniently coincided with its funding renewal, which NASA got. As if a tiger has been wagged by its tail, the press leashed out its most vicious attack on NASA and the theory of ozone depletion. Books titled The Holes in the Ozone Scare, Trashing the Planet and Rush Limbaugh's The Way Things Ought to Be were released. Rush Limbaugh, a radio critic, made the best out of it and almost became an over night celebrity lambasting and knocking down the dangers from ozone layer depletion. Limbaugh called NASA scientists, "dunderhead alarmists and prophets of doom."

Suddenly, springing from nowhere, were scientists proposing arguments to discredit the great ozone scare. Those opposing the ozone danger theory concluded that there is enough natural production of chlorine in the atmosphere which dwarfs the contributions made by CFCs. The seawater contributes 600 million tons of chlorine, 36 million come from volcanos, 8.4 million from biomass burning and 5 million from ocean biota. The CFCs contribute less then one million tons of chlorine per year. Since the ozone layer has survived this natural production of chlorine for ages, what is the problem now with just one seventh of a percent additional contribution through CFCs. The controversy became so fierce that a petition was circulated among the scientific community to renege the ozone theory. Among those who have signed this petition include such revered names as Nobel-laureate Derek Barton.

Where does that leave us? Actually perplexed and resolved, both; what came out of the aftermath of this battle was a clearer understanding of the phenomenon. The arguments as they pan out today are as follows. The chlorine generated by the natural sources including evaporation from oceans produces an inorganic, water soluble form of chlorine, as sodium chloride and hydrochloric acid; both of which get washed down in the lower atmosphere and can not reach the upper atmosphere. The CFCs are light, insoluble and almost indestructible; they can not get washed down and therefore easily find their way to upper atmosphere. Upon reaching the higher levels of atmosphere they break down into hydrochloric and hydrofluoric acids; chlorine gas is formed which reacts with the ozone molecules. The proof of this theory finally came from the determination of the relative proportion of hydrofluoric and hydrochloric acid in the upper atmosphere sampled by high altitude spy planes; it could only come from CFCs--in that proportion. The study which failed to observe increase in the intensity of ultraviolet radiation was faulted on the basis of wrong instrumentation used and we are now back to the original assertion that ozone depletion is for real. Whereas the real hole opening is taking place in the Antarctic, it is spreading all over and unless checked soon, it will expose us all to the extreme furies of sun; the doomsday scenario seems quite real with the depletion of ozone over our heads.

How does it affect us and what can we do about it? First, we must reaffirm the belief that there is only one atmosphere; that's the only cover we got-whether you live in Timbaktu, St. Louis or Thatta. Fortunately, the lack of affordability of cosmetics by the masses keeps us the least contributor to the world menace of CFCs; but if you are one of those fortunate consumer that uses aerosol sprays, insist on using only non-CFC products. Secondly, countries who have signed the Montreal Protocol are fast meeting their commitments. The most serious threat comes from using CFCs in refrigeration and air conditioning. Just now we have begun seeing refrigerators and air conditioners that do not use CFCs. They are still more expensive than the CFC units but it is hoped that soon they will entirely switchover to the non-CFC system.

What needs to be learned from this unfolding saga of ozone story is the spirit of salvaging environment by the worldwide community. It is refreshing to see what the human race, despite the Nature's inculcated design to destroy, maintains and respects the rights of the future generations. We should critically examine the importance placed on caring for our environment and then evaluate how we contribute to the cause. It is only a matter of life.

[15 December 1993 The Daily Dawn]