RETROSPECTIVE

F. Sherwood Rowland: A man of science, vision, integrity, and kindness

Barbara J. Finlayson-Pitts1 Department of Chemistry, University of California, Irvine, CA 92697-2025

A man does what he must—in spite of per- sonal consequences, in spite of obstacles and dangers and pressures—and that is the basis of all human morality.

—Sir Winston Churchill, British politician (1874–1965)

. Sherwood (Sherry) Rowland was best known for his ground- Fbreaking work on the impact of chlorofluorocarbons (CFCs) on stratospheric ozone. Although this topic was controversial at the time, Sherry courageously persevered in the face of “obstacles, dangers and pressures.” His research was ultimately proven correct and was recognized by sharing the 1995 Nobel Prize in Chemistry. Sherry was also a giant in the broader chemical community, with studies running from hot atom reactions to atmospheric concentrations of trace Joan Rowland and F. Sherwood (Sherry) Rowland. gases, including greenhouse gases, and more recently the use of breath analysis as I first met Sherry when I was a young role of the OH radical was recognized. fi a marker of disease and drug ef cacy. graduate student in the early 1970s. There This finding sparked an explosion of Sherry served as Foreign Secretary of the was a very active group of researchers in research activity on the chemistry of the National Academy of Sciences from 1994 physical and photo-chemistry in Southern plethora of reactive gas-phase organics in to 2002 and President of the American California and the field that became tropospheric air. Association for the Advancement of atmospheric chemistry was just emerging. There had been relatively little work Science in 1992. However, in addition to There were a number of photochemistry on stratospheric chemistry since the sem- his science, Sherry was well known for conferences held during that time, at which inal studies of Sydney Chapman, who his vision, integrity, and kindness, attrib- “beginners” such as I had unique oppor- elucidated the natural odd oxygen cycles utes that encompassed his entire life tunities to interact with the leaders in the that form and destroy ozone in the upper and career. field: this included Sherry. My fond atmosphere. In 1970–1971, Paul Crutzen Sherry passed away peacefully at home memories of those interactions are of (1, 2) elucidated important additional on March 10, 2012 at age 84 from com- a patient, interested, and supportive senior cycles involving oxides of nitrogen in the plications associated with Parkinson’s scientist who went out of his way to stratosphere that could lead to ozone disease. He is survived by his wife Joan, encourage us youngsters in the field. destruction, and the impact of direct daughter Ingrid, son Jeff, daughter-in-law This perception was borne out over many emissions of NOx into the stratosphere Christie, and two grandchildren, Taylor subsequent decades of interactions with was discussed by Harold Johnston in 1971 and Lindsay. Sherry, including over recent years at UCI, (3). In 1974, Richard Stolarksi and Ralph Sherry was born in Delaware, OH in where I was most fortunate to count my- Cicerone (4) proposed new ozone-de- 1927 and entered Ohio Wesleyan as an self as his friend and colleague. stroying cycles involving chlorine that undergraduate at the age of 15, from which The 1970s were an exciting time in could be important if there were sufficient he graduated (after time out in the Navy chemistry and especially in Southern sources of chlorine into the stratosphere. during the war) with majors in chemistry, California, which was then known as the James Lovelock, inventor of the electron physics, and mathematics. He completed smog capital of the world. Coming out of capture detector, which is widely used in his PhD at the University of Chicago under the 1960s, environmental issues had risen gas chromatography, had applied this Willard Libby and then joined Princeton to the forefront of public concern, and technique to measure CFCs in air part- University as an instructor for 4 y. He the role that chemistry played in both the per-trillion concentrations. At that time, moved to the University of Kansas in causes and the cures of many environ- Sherry’s research on hot atom chemistry 1956 as an assistant professor, where he mental problems was becoming apparent. was funded by the Atomic Energy earned tenure after only 2 y. In 1964 Arie Haagen-Smit’s research at the Commission (AEC) who, thankfully, he accepted the challenge of becoming California Institute of Technology, begin- the founding chair of the department of ning in the 1950s, had set the stage for chemistry at the University of California understanding the importance of chemis- Author contributions: B.J.F.-P. wrote the paper. at Irvine (UCI), which opened its doors try in the lower atmosphere (troposphere), The author declares no conflict of interest. to students in 1965. but it was not until 1970 that the central 1E-mail: bjfi[email protected].

www.pnas.org/cgi/doi/10.1073/pnas.1212354109 PNAS Early Edition | 1of2 Downloaded by guest on September 23, 2021 understood and encouraged curiosity- scientific truth and translating the im- basketball, and tennis, were often dem- driven research by their grantees. On plications for public health and welfare. onstrated during spontaneous games of a train from Salzburg, Austria after a con- It was certainly not an easy time, with various sorts at conferences. ference, an AEC program manager invited many attacks on his science and personal Sherry had tremendous vision that was Sherry to attend a meeting in Florida at integrity coming from many different apparent not just in his science, but in which the Lovelock work was discussed. In quarters. However, with the first reports the leadership he brought to everything in these early days, the idea that nonreactive of the Antarctic “ozone hole” in 1985 and his life. He came to Irvine in 1964 when organics, such as CFCs released into the the subsequent inescapable conclusion it was not much more than a series of troposphere at the earth’s surface, could after some intense field and laboratory ranches. He played a major role in the impact the stratosphere and ultimately studies that this ozone hole was caused development not only of the Department have global impacts would have been re- by CFCs, the work was completely vindi- of Chemistry, but also the campus as garded as absurd, at best. However, Sherry cated. In 1987, the first international a whole. Institutions and departments can was not one to gloss over “accepted wis- agreement on CFCs took shape in the either be propelled forward or held back dom” (or lack thereof), and with the AEC’s form of the Montreal Protocol, which for a long time by the initial leadership and blessing and support, decided to trace the continues to serve today as a model for vision; Sherry’s impact, particularly for the atmospheric fate of CFCs in his character- international collaboration to address Department of Chemistry, was most cer- istic quantitative scientific approach. a global problem. tainly in the former category. Sherry also In 1973, Mario Molina joined Sherry’s Although much of the recognition of led in the founding of the Earth System group as a postdoctoral fellow and began Sherry’s research has focused on the CFC Science Department at UCI, which within working on the CFC issue. Sherry and work that led to the Nobel Prize, there a few short years became internationally Molina quite rapidly came to the conclu- were many other important contributions recognized. sion that, given the lack of reactivity in the over his scientific career. These con- Sherry was a man of enormous integrity. troposphere (which had been regarded as tributions include his early work on hot Not many could have withstood the a plus), CFCs would be transported into atom chemistry and, after the CFC dis- onslaught of both scientific and personal the stratosphere. At sufficiently high alti- covery, his measurements of trace atmo- attacks to which he was subjected over tudes, CFCs would be exposed to UV that spheric gases and their trends with time, a decade before the Rowland/Molina hy- was energetic enough to dissociate and which began in the mid-1970s when Don pothesis on CFCs was accepted. However, form chlorine atoms. Based on the known Blake joined his group as a PhD student. Sherry continued to speak his truth quietly chemistry at the time, this exposure would The research carried out during their very and clearly, without demonizing his critics, set off chain reactions leading to increased productive collaboration over many years but remaining steadfast in his science. loss processes for ozone, and hence lower since continues at UCI, where Don is a full A characteristic of Sherry that is not as steady-state ozone concentrations in the professor. This research includes meas- often acknowledged is his kindness. I saw stratosphere. Given the key role of ozone urements of the CFCs, which showed a this first as the young graduate student in filtering UV before it reaches the turnover in their previous rates of with whom he generously shared his time troposphere, the global impacts were likely increase as the Montreal Protocol and and knowledge, remarkably making me to be significant. This work was published subsequent agreements came into play, feel as if I were his equal (which could in Nature (5) in 1974, forming the basis of which must have given Sherry great satis- not have been further from the truth!). the joint award of the Nobel Prize in faction. These measurements also include However, Sherry treated everyone with the Chemistry to Sherry, Mario Molina, and a number of important species, such as same respect and interest, from under- Paul Crutzen in 1995. methane, an important greenhouse gas, graduates to fellow scientists to politicians Sir Winston Churchill is quoted as and reactive impurities in propane that are to the Pope. He was the epitome of the saying, “Man will occasionally stumble important in generating air pollution in lines in Rudyard Kipling’s poem “If”: over the truth, but usually manages to pick Mexico City. Sherry was also very excited “If you can talk with crowds and keep your himself up, walk over or around it, and over recent years by a new direction in virtue, or walk with Kings—nor lose the carry on.” Fortunately for the world and which his atmospheric measurement common touch...” science in general, Sherry and Mario, techniques were applied to breath analysis Finally, a retrospective on Sherry would having discovered the truth, along with as markers of disease and the efficacy of not be complete without recognizing the others, such as Ralph Cicerone, dedicated various medications. key role played by Joan, his wife and life themselves to not only furthering the However, there was much more to partner in all things. Sherry simply would science but also to making the public Sherry than superb science. He loved not have been Sherry without her support, aware of its implications. This dedication both opera and athletics (an interesting advice, and full partnership in all their lead to regulatory action on CFCs in combination). When he was a graduate endeavors. In a US Senate hearing in aerosol cans by the US Congress in 1978 student at Chicago, Sherry was on a semi- 1986, Sherry was asked what he would do which, in retrospect, was an incredibly fast professional baseball team in Oshawa, “if he were king.” His response? “I would response. Such action would never have ON, Canada, and was managing this team ask the queen.” Their 60th wedding been the case were it not for Sherry’s when it won the championship in 1950. anniversary would have been on June 28 courage and steadfastness in speaking the His athletic abilities, honed in baseball, of this year.

1. Crutzen PJ (1970) The influence of nitrogen oxides on 3. Johnston H (1971) Reduction of stratospheric ozone by 5. Molina MJ, Rowland FS (1974) Stratospheric sink for the atmospheric ozone content. Q J R Meteorol Soc 96: nitrogen oxide catalysts from supersonic transport ex- chlorofluoromethanes: chlorine atom-catalyzed de- 320–325. haust. Science 173:517–522. struction of ozone. Nature 249:810–812. 2. Crutzen PJ (1971) Ozone production rates in an oxygen- 4. Stolarksi RS, Cicerone RJ (1974) Stratospheric chlo- hydrogen-nitrogen oxide atmosphere. J Geophys Res rine: a possible sink for ozone. Can J Chem 52:1610– 76:7311–7327. 1615.

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