F. Sherwood Rowland

1927 - 2012

F. Sherwood Rowland: The Sentinel of the Stratosphere

F. Sherwood Rowland (1927–2012), known to friends and colleagues as "Sherry," was a towering figure in 20th-century science. His work transformed chemistry from a discipline often associated with industrial production into a vital tool for planetary stewardship. By identifying the chemical mechanism by which man-made compounds destroy the Earth’s ozone layer, Rowland bridged the gap between laboratory research and global environmental policy.

1. Biography: From the Midwest to the Stratosphere

Frank Sherwood Rowland was born on June 28, 1927, in Delaware, Ohio. A child prodigy, he graduated from high school at age 15 and enrolled at Ohio Wesleyan University. His education was briefly interrupted by a stint in the U.S. Navy as a radar operator (1945–1946), after which he returned to complete his undergraduate degree in chemistry, physics, and mathematics.

Rowland pursued his graduate studies at the University of Chicago, then a hotbed of nuclear chemistry. He earned his Ph.D. in 1952 under the mentorship of Willard Libby, the Nobel laureate who developed carbon-14 dating. This training in radiochemistry—tracking how trace amounts of atoms move through systems—would become the foundation of his later atmospheric work.

Academic Trajectory:

Princeton University (1952–1956): Instructor in the Chemistry Department.
University of Kansas (1956–1964): Professor, where he specialized in "hot atom" chemistry (the study of atoms with high kinetic energy from nuclear processes).
University of California, Irvine (1964–2012): Founding Chair of the Chemistry Department. Rowland spent the remainder of his career at UCI, building it into a world-class research institution.

2. Major Contributions: The CFC-Ozone Hypothesis

In 1973, Rowland attended a lecture on the presence of chlorofluorocarbons (CFCs)—chemicals used in aerosol sprays and refrigeration—in the atmosphere. While other scientists noted that CFCs were chemically inert and harmless at ground level, Rowland asked a pivotal question: What eventually happens to them?

In collaboration with his postdoctoral fellow, Mario Molina, Rowland developed the Rowland-Molina Hypothesis (1974). Their research revealed a terrifying chain reaction:

Transport: Because CFCs are chemically stable, they do not dissolve in rain or react with other chemicals in the lower atmosphere. Instead, they drift upward into the stratosphere.
Photolysis: Once they reach the upper atmosphere, intense ultraviolet (UV) radiation breaks them apart, releasing free chlorine atoms.
Catalytic Destruction: A single chlorine atom acts as a catalyst, breaking apart ozone (O₃) molecules into oxygen (O₂). Crucially, the chlorine atom is not consumed in the process; one chlorine atom can destroy upwards of 100,000 ozone molecules before being removed from the atmosphere.

This discovery was alarming because the ozone layer shields the Earth from DNA-damaging UV radiation, which causes skin cancer, cataracts, and damage to marine ecosystems.

3. Notable Publications

Rowland authored over 400 scientific articles, but his most influential work remains the paper that alerted the world to the ozone crisis.

"Stratospheric sink for chlorofluoromethanes: chlorine atom-catalysed destruction of ozone" (Nature, 1974): Co-authored with Mario Molina, this is considered one of the most consequential scientific papers of the 20th century. It provided the theoretical framework for ozone depletion.
"Photochemistry of stratospheric ozone" (1991): A comprehensive review that consolidated nearly two decades of research following the initial discovery.
"Methane in the Global Atmosphere" (1982): Beyond CFCs, Rowland was an early researcher into the rising concentrations of methane and its role as a potent greenhouse gas.

4. Awards & Recognition

Rowland’s work eventually earned him the highest honors in science, though recognition was delayed by years of industry opposition.

Nobel Prize in Chemistry (1995): Shared with Mario Molina and Paul Crutzen "for their work in atmospheric chemistry, particularly concerning the formation and decomposition of ozone."
Tyler Prize for Environmental Achievement (1983): Often called the "Nobel of the Environment."
Japan Prize (1989): For his contributions to environmental science and technology.
President of the American Association for the Advancement of Science (AAAS): Served in 1992.
Albert Einstein World Award of Science (1994).

5. Impact & Legacy: The Montreal Protocol

Rowland’s legacy is unique because it resulted in tangible, global legislative change. Initially, his findings were met with fierce resistance from the chemical industry. DuPont and other manufacturers launched PR campaigns to discredit him, and for a decade, Rowland was largely blacklisted from industry-funded speaking engagements.

However, the discovery of the "Ozone Hole" over Antarctica by British researchers in 1985 provided the empirical "smoking gun" that Rowland’s theory was correct. This led to the Montreal Protocol (1987), an international treaty to phase out the production of CFCs. It remains the most successful environmental treaty in history; the ozone layer is currently on a path to full recovery by the mid-21st century.

Rowland also paved the way for modern climate science by demonstrating that human activity, even in trace amounts, could alter the chemistry of the entire planet.

6. Collaborations

Mario Molina: His most famous collaborator. Molina was the postdoc who performed many of the initial calculations in Rowland's lab. Their partnership is a classic example of mentor-mentee synergy.
Donald Blake: A long-time collaborator at UC Irvine. Together, they conducted global air sampling, traveling to remote locations to measure the rising concentrations of gases like methane and methyl chloroform.
Paul Crutzen: Though they worked independently, Crutzen’s work on nitrogen oxides and their effect on ozone complemented Rowland’s research on chlorine.

7. Lesser-Known Facts

A Talented Athlete: Standing 6'5", Rowland was an accomplished athlete. During his graduate years at Chicago, he played semi-professional baseball and was a standout on the university's basketball team. He often said the discipline of sports helped him handle the rigors of scientific research.
The "End of the World" Conversation: When Rowland first realized the implications of his research in 1973, his wife, Joan, asked how the work was going. He reportedly replied:
"It’s going very well. It just looks like it might be the end of the world."
Scientific Activism: Unlike many scientists of his era who believed researchers should remain neutral, Rowland was a vocal advocate for policy change. He famously stated:
"What's the use of having developed a science well enough to make predictions if, in the end, all we're willing to do is stand around and wait for them to come true?"
The "Sherry" Moniker: Despite his imposing height and Nobel status, he insisted on being called "Sherry" by students and colleagues alike, maintaining a famously approachable and humble demeanor throughout his life.