|Our Planet (UNEP, 1999, 36 p.)|
Dr. Joe Farman, the 'discoverer' of the Antarctic ozone hole, is a consultant to the European Ozone Research Co-ordinating Unit, Cambridge, United Kingdom.
Fifteen years ago, at just this time of the year, I was waiting to learn the results of ozone measurements being made at the British Antarctic Survey bases. The results confirmed that a dramatic change in Antarctic ozone climatology was taking place. Soon the world was to be talking about the 'ozone hole'.
Concern about man's impact on the ozone layer became an international issue in 1970. Fears were first expressed about the projected fleets of supersonic stratospheric transport aircraft; but only Concorde went into service. In 1974 attention shifted to the chlorofluorocarbon (CFC) industry. Production of CFCs had quadrupled since 1960, they had spread worldwide, and their concentrations in the atmosphere were steadily increasing. American scientists pointed out that they were so stable that they would eventually reach the stratosphere, that they would release chlorine there, and that an ozone-destroying chain reaction would ensue.
PROGRESS SLOW - BUT SURE
A vigorous debate followed, but there was no concerted action. The United States of America, Canada and Scandinavian countries banned the use of CFCs as aerosol propellants. Other European countries, on the other hand, decided that the capacity for producing the chemicals should not be expanded, but that no specific restrictions on their use were needed. In 1978 UNEP established a coordinating committee to try to get international action. Progress was very slow, but eventually 23 countries signed the Vienna Convention in March 1985. The Convention acknowledged that there-was a problem and agreed to collaborative studies, but the issue of controlling CFCs was deferred.
The discovery of the ozone hole helped bring about a breakthrough, in the agreement of the Montreal Protocol in September 1987. Its controls on CFCs were initially absurdly weak, but importantly it provided for frequent reviews - though these did not begin until 1990. Controls were successively tightened under these provisions in London, 1990, Copenhagen, 1992, Vienna, 1995 and Montreal, 1997 - and this winter the Parties are meeting again in Beijing.
The prospects for ozone recovery remain poor. Though chlorine reached its peak in the atmosphere in 1994 and has since decreased slowly, bromine (which also depletes ozone) is still increasing. There needs to be a fresh impetus to attempts to control its sources - halons and methyl bromide.
No halons have been made in developed countries since 1994, but large amounts are still used and stored in them, within the terms of the Montreal Protocol. Elsewhere production capacity has risen, especially in China. Freshly made halon is smuggled into developed countries falsely labelled as internally recycled material. Meanwhile, new evidence from Antarctic snow suggests that methyl bromide increased rapidly in the 1970s and 1980s, implying that some anthropogenic source has yet adequately to be quantified and controlled. Furthermore, increases in greenhouse gases exacerbate ozone depletion by making the stratosphere colder, even as they warm the Earth's surface.
CAPTURING MASS MARKETS
There is still a lack of commitment to prudent long-term goals. We need to break the cycle by assisting new halocarbon-free and energy-efficient technologies to capture mass markets against competition from the obsolescent established giants. We should try to protect the ozone layer, combat global warming and assist developing countries by one-off investment wherever possible.
Such is our industrial capacity that we can, in just a decade or two, affect the world so severely that it may take a century or more to recover. This is what happened over ozone depletion, where we performed what in retrospect will surely be seen as an unnecessary experiment. That the consequences have not been more severe must be attributed to luck rather than good judgement.
When will we learn?