Harold “Hal” Johnston, a UC Berkeley professor emeritus of chemistry, died of natural causes at his home in Kensington, Calif., on Oct. 20. He was 92.
Johnston first came to the Berkeley campus when he was made a professor of chemistry in 1957 and served as the dean of the campus’s College of Chemistry from 1966 to 1977. He continued to teach until his retirement in 1991.
“It’s sad to lose a good friend and colleague,” said Ronald Cohen, a campus professor of chemistry and director of the Berkeley Atmospheric Science Center. “He lived a fabulous life, and we honor his memory. It’s that kind of mix of feelings where you want someone to live forever but when their time comes, it comes.”
Born in Woodstock, Ga., on Oct. 11, 1920, Johnston was originally not expected to live past his twenties after contracting rheumatic fever when he was 13.
“I found out that the average survival time was about 15 years,” Johnston said in an oral history project of his life conducted in 1999 by UC Berkeley. “I’ve had a moving 10-year life expectancy; almost every decade, I have understood that I probably wouldn’t last till the next one.”
Johnston obtained a degree in chemistry from Emory University in 1941 and went to the California Institute of Technology for graduate studies, obtaining a doctorate in 1948.
The professor then worked at the chemistry departments for Stanford and Caltech before coming to Berkeley.
One of Johnston’s lasting legacies is an article he published in Science magazine showing that aircraft emissions in the stratosphere were depleting the Earth’s ozone layer, according to Cohen. Johnston’s original research found that nitrogen oxide emitted from supersonic flights contributed to the depletion.
“Lots of people weren’t prepared to believe what he showed,” said Dudley Herschbach, a professor emeritus of chemistry at Harvard University. “He was really one of the great pioneers in stratospheric chemistry and had a very major impact on everyone who went into the field.”
Herschbach, who won a Nobel Prize for chemistry in 1986, credits Johnston with having a huge influence on his academic life while the latter was working at Stanford University’s chemistry department in the 1950s.
“It was really him that inspired and intrigued me about trying to understand what happen at the molecular level in chemical reactions,” Herschbach said. “Hal was my adviser all the way through college, and he’s my most important mentor into becoming a scientist.”
While Johnston was seriously dedicated to his work, he was also highly regarded by his students and colleagues for his sense of humor and caring attitude. Herschbach said that Johnston once invited him on a hiking and camping trip after being called to a Naval research lab to do consulting work.
“To take a sophomore out to be his partner, visit a lab, go hiking and then talk about philosophy for four days – that’s pretty special,” he said. “How many undergraduates get a professor who personally is so much a wonderful friend and mentor?”
For his work in atmospheric chemistry, Johnston received a number of awards and prizes, including the National Medal of Science, the Tyler World Prize for Environmental Achievement and the National Academy of Sciences Award for Chemistry in the Service to Society.
Johnston is survived by his wife, Mary Ella Johnston, their four children, Shirley Johnston Anderson, Linda Banster, David Johnston and Barbara Schubert, and grandchildren and great-grandchildren.
“He was 92 and in good health almost to the very end,” Cohen said. “He did great work and had a family he really loved and cherished and got to spend time with them until the end.”
Contact Andy Nguyen at [email protected].