Frank Sherwood Rowland
Rowland, Frank Sherwood (1927-) is an American chemist. He shared the 1995 Nobel Prize in chemistry for his pioneering contributions explaining how the earth's protective layer of ozone (a form of oxygen most often found in the upper atmosphere) is formed and broken down through chemical processes in the atmosphere.
Rowland shared the prize with his research partner, the Mexican-born American chemist Mario Jose Molina, and with the Dutch chemist Paul Josef Crutzen, who worked independendy on related research. Rowland's work led to worldwide restrictions on the production of chlorofluorocarbons (CFC's), industrially produced chemical compounds that were breaking down the protective ozone layer.
Rowland was born on June 28, 1927, in Delaware, Ohio. His father, Sidney Rowland, was a professor and chair of the mathematics department at Ohio Wesleyan University in Delaware. His mother, Margaret (Drake) Rowland, taught Latin at a local school. He had two brothers.
As a child, Rowland attended public schools in Delaware. An excellent student, he skipped fourth grade. Rowland was especially good at mathematics. In high school, he studied mathematics, science, history, English, and Latin in preparation for college. For several summers during the early 1940's, Rowland worked at the local volunteer weather station collecting data on daily high and low temperatures and levels of precipitation.
In 1943, Rowland graduated from high school a few weeks before his 16th birthday. Most of the young men in his class joined the military to fight in World War II (1939-1945), but Rowland was too young to enlist. He instead entered Ohio Wesleyan University, where he took science courses and played on the university basketball and baseball teams. After he turned 18 in 1945, Rowland joined the U.S. Navy and began training to become a radar operator. World War II ended later that year, and Rowland was discharged in 1946 after 14 months of service. He returned to his studies at Ohio Wesleyan. In 1948, he received a B.A. degree with majors in chemistry, mathematics, and physics.
Rowland went to Illinois in the fall of 1948 to attend the University of Chicago, the school where both of his parents had earned their Ph.D. degrees. He studied the chemistry of radioactive atoms with his faculty adviser, the American chemist Willard Frank Libby. In 1947, Libby had discovered radiocarbon, or carbon 14, and found a way to use it to determine the age of prehistoric plant and animal remains—a discovery for which he would receive the 1960 Nobel Prize in chemistry. The path of radiocarbon atoms could be traced through a chemical reaction in an organism, thus enabling scientists to better understand that reaction. Rowland wrote his doctoral thesis on the chemical state of radioactive bromine atoms produced through a cyclotron, a device that spins tiny bits of matter in a circular path at high speed. He received a Ph.D. degree in chemistry from the University of Chicago in 1952.
In September 1952, Rowland became an instructor in the chemistry department at Princeton University in New Jersey. During the summers from 1953 to 1955, he conducted research in tracer chemistry at the Brookhaven National Laboratory on Long Island in New York.
Rowland became assistant professor of chemistry at the University of Kansas in 1956. From 1956 to 1970, his research was supported by the U.S. government's Atomic Energy Commission. At Kansas, Rowland led a group of radiochemists (scientists who study radioactive elements) researching the chemical reactions of tritium atoms. He rose through the academic ranks to become a full professor in 1963.
In August 1964, Rowland became professor of chemistry and chairman of the chemistry department at the new Irvine campus of the University of California. He retired as department chairman in 1970 but retained his position as professor.
In 1972, Rowland heard a lecture by the British scientist James Lovelock that mentioned the movement of CFC's in the atmosphere. CFC's do not readily undergo chemical reactions. Scientists at that time therefore believed that CFC's caused no harmful effects. After CFC's are released into the atmosphere, they rise slowly. Lovelock suggested tracking the CFC's to learn more about the atmosphere. He had developed a scientific instrument to measure CFC levels. Rowland knew that when CFC's reached the upper atmosphere, the sun's ultraviolet radiation would break them apart. He decided to study them to determine what would eventually happen to them in the atmosphere.
Rowland began to study CFC's in 1973. Mario Molina, who had just completed his Ph.D. work as a laser chemist, joined Rowland in this research. Within three months, they realized that some of the molecular fragments resulting from the breakdown of CFC's reacted with ozone, decreasing the amount of it. The ozone layer in the upper atmosphere shields the earth from 95 to 99 percent of the sun's ultraviolet rays. Over-exposure to these rays is a cause of skin cancer. Thus, a decrease in the amount of ozone poses a danger to human life.
Rowland and Molina calculated that if CFC production were to continue at the same levels, the ozone layer would be depleted (decreased) by 7 to 13 percent. In June 1974, Rowland and Molina published their findings in the journal Nature. Later that year, they began to discuss their research at scientific meetings and recommend that production of CFC's be stopped. At that time, CFC's were widely used as propellants in aerosol spray cans, as coolants in refrigerators and air conditioners, and in insulation. In 1978, the U.S. government banned the use of CFC's in aerosol cans. However, the ban did not affect the use of CFC's as refrigerants or in insulation.
Since the late 1970's, scientists have observed a seasonal depletion (thinning) of ozone over Antarctica. They found that in the spring the amount of ozone decreases by up to 50 percent for about two months, creating an ozone hole. Satellite surveys by the National Aeronautics and Space Administration (NASA) in 1985 confirmed the existence of a continent-sized hole in the ozone layer over Antarctica. In 1992, another potential ozone hole was discovered, this one over the Arctic. Scientists have attributed the extreme depletion of the ozone layer over the poles to weather patterns and season sun that promote an unusually rapid cycle of chlorine-ozone chain reactions.
In a treaty called the Montreal Protocol on Substances That Deplete the Ozone Layer, which took effect in 1989, the major CFC-producing nations agreed to gradually stop producing the chemicals. By 1996, most industrialized countries, including the United States, had ended production of CFC's. Rowland's efforts in alerting the scientific community of the threat that CFC's posed to the ozone layer were rewarded with the Nobel Prize in 1995.
Rowland has received many other awards and honors throughout his career. The American Chemical Society gave him the Tolman Medal in 1976 and the Peter Debye Award in 1983. Rowland received the Charles A. Dana Award for Pioneering Achievement in Health in 1987, the Japan Prize in Environmental Science and Technology in 1989, the Tyler Prize in Ecology and Energy (now called the Tyler World Prize in Environmental Achievement) in 1993, and the Roger Revelle Medal of the American Geophysical Union in 1994. Rowland became a member of the American Academy of Arts and Sciences in 1977, the National Academy of Science in 1978, and the National Philosophical Society in 1995. He has published more than 300 articles in scientific journals.