Instead of saying, “I tripped up”, you have to use the words, “I had a fall.”

Having conversations with young people who you remember being born.

Not being able to fend for myself and being a burden to others.

One by one the more vigorous sports and exacting games fall away. Exceptional exertions are purchased only by a more pronounced and more prolonged fatigue. Muscles may relax, and feet and hands slow down; the nerve of youth and manhood may become less trusty. But painting is a friend who makes no undue demands, excites to no exhausting pursuits, keeps faithful pace even with feeble steps, and holds her canvas as a screen between us and the envious eyes of Time or the surly advance of Decrepitude. Happy are the painters, for they shall not be lonely.

The advice that I would give is try to find something that you like. Try to devote your energies to being very good at it. Try to achieve excellence. Don’t necessarily have as a goal success or getting prizes or whatever, but just doing very good work. And work hard. Keep working at it. Be patient. Realize that you don’t always see the benefits of what you’re doing, short-term. But in the end, the activities that I do, for example, scientific research, can be extremely rewarding. It’s really a very fascinating career.

Sherry offered me a list of research options: the one project that intrigued me the most consisted of finding out the environmental fate of certain very inert industrial chemicals – the chlorofluorocarbons (CFCs) – which had been accumulating in the atmosphere and which at that time were thought to have no significant effects on the environment. This project offered me the opportunity to learn a new field – atmospheric chemistry – about which I knew very little; trying to solve a challenging problem appeared to be an excellent way to plunge into a new research area.

At first the research did not seem to be particularly interesting – I carried out a systematic search for processes that might destroy the CFCs in the lower atmosphere, but nothing appeared to affect them. We knew, however, that they would eventually drift to sufficiently high altitudes to be destroyed by solar radiation. The question was not only what destroys them, but more importantly, what the consequences are.

Although my years at Irvine were very productive, I missed not doing experiments myself because of the many responsibilities associated with a faculty position: teaching courses, supervising graduate students, meetings, etc. After spending seven years at Irvine as Assistant and then Associate Professor, I decided to move to a non-academic position. I joined the Molecular Physics and Chemistry Section at the Jet Propulsion Laboratory in 1982. I had a smaller group – only a few postdoctoral fellows – but I also had the luxury of conducting experiments with my own hands, which I enjoyed very much.

I certainly want to continue trying to understand how the global environment functions. The earth as a system is a very complicated one. And to understand it, we need very many disciplines, very many different scientists working together. I want to continue working with my specialty, which is chemistry, with the atmosphere. There is still much to learn about chemical reactions that occur out there in the air, in the atmosphere. So one of my projects now is to really learn more about this pollution that occurs in cities and that is spreading more through the globe. To learn it in enough detail so we can better tackle it, we can better come up with new ways of using energy, for example, that are not so damaging to the environment.

I have also benefited from teaching; as I try to explain my views to students with critical and open minds, I find myself continually being challenged to go back and rethink ideas. I now see teaching and research as complementary, mutually reinforcing activities.