music Molina and Rowland made some very important points in their 1975 paper. The main one being that the lifetime of the chloroflurocarbons is extremely long-50 to 100 years. There’s no way to destroy these gases. Once you put them in, they’ve got nowhere to go except up to the ozone layer where they’re going to They’re gonna destroy it. The ozone is a protective layer that absorbs very energetic radiation and the CFCs won’t break up until they get above most of that and so it’s not accidental that the CFCs are tied in with the ozone layer. They are protected until they get up to an altitude of 9-10 miles before you start seeing effects of the reaction with solar, ultra-violet radiation…. Experts in the field, atmospheric scientists and atmosphereic chemists, in general, accepted it as something plausible, something that was likely to happen Our goal at some point became to actually communicate these findings to society with the hope that something could be done. It was hard to communicate to people that something that they couldn’t feel, couldn’t taste, couldn’t see, didn’t cause any obvious respiraotory problems, was in fact a serious threat in the form of long term exposure leading to increased risk of cancer…a problem that had it been allowed to languish and grow would have created more health problems in the form of long term exposure leading to increased risk of cancer. Soon after I arrived at NASA, I was asked to take over the management of a U.S.-lead assessment of ozone depletion. it was mandated by Congress that every two years, NASA had to write a state of the ozone layer. What seemed logical to me was that if we’re going to negotiate an international treaty on stratospheric ozone depletion then there needed to be one international assesment where the scientists around the world spoke with one voice. And so during that period, 1980-1985, I worked with the scientific community to get together a true international assesment that could be the basis for informed international negotiations. AsI look back at what we did in implementing the Montreal Protocol, I think it is one of the most successful cooperative efforts that I have ever seen between a regulatory agency, the EPA, and a regulatedagency, the department of defense. the NGOs, their suppliers, and their counterparts in other countries. And the fact of the matter is it worked. It was incredibly successful. Suddenly there was a paper by Joe Farman who had a Dobson instrument located in Antartica at Halley Bay that suggested in the Springtime-August, September, October period- there was a sudden depletion of ozone. A series of international experiments was done. The biggest one was in 1987 where there were some ground based observations, two very well-equipped aircraft, the DC-8 and the ER2, and some satellite observations, and it became very clear, very quickly, that we humans were having a direct effect that was unambiguous on the ozone layer. I have to say it was tremendously exciting to go to Antarctica. You realize when you’re there how incredible remote and beautiful and untouched the place is. And it’s so ironic to sit there and watch the Ozone layer dissappear. I think the key development in industry was when the Dupont company, which was the major U.S. manufacturer of CFCs, concluded that the scientists were right. The Montreal Protocol was signed in Sept. 1987. It was shortly after that that the results of the Antarctic aircraft expedition came out. And the decision was made on Friday afternoon that we would committ to a total phase out of CFCs. It was the first time i had ever seen companies come together on something that if they had withheld information and kept it proproetary it would give them a competitive advantage. I think the number one lesson is that you have to have really good science. It has to be done extremely carefully. It has to be verified by multiple sets of observations and multiple models. We need to have coordinated research globally and international assessments so that the scientific community talks with one voice to the international negotiators. Because of the spirit of cooperation with the govenrment setting standards that were challenging, yet flexible, allowed industry to innovate, industry came forward and everyone worked togetehr to make this happen. I think the intersection of science and public policy…there’s a lesson there. Science really drove that. Science is what made me confident that the public policy position I was advocating was sound, was important for the future. We had a substantial scientific establishment and they were right on this issue as it turns out. And when it was just a hypothesis, later it was confirmed. And i think it’s the same with climate change. Now we’re getting not just computer models but observations so there’s every reason to follow the same course and listen to the same scientific opinons.