Mario José Molina is a Mexican-born American chemist who was jointly awarded the 1995 chemistry prize, along with F. Sherwood Rowland (US) and Paul J. Crutzen (Netherlands), “for their work in atmospheric chemistry, particularly concerning the formation and decomposition of ozone.” Most people are aware of the threat to the ozone layer, which shields the Earth from solar radiation, but it was as early as the 1970s that Molina and Rowland first highlighted the problem. Their work led to an international movement to cut the use of chlorofluorocarbon (CFC) gases.
Molina was born in Mexico City in 1943. His father was a lawyer and lecturer who later became an ambassador.
Mario attended school in Mexico City and Switzerland and developed an early interest in chemistry, helped by his aunt, who was a chemist. In 1960, he entered the Universidad Nacional Autonoma de Mexico, studying chemical engineering and gained a BSc in 1965 before going on to earn a postgraduate degree from the University of Freiburg, West Germany in 1967. After a time studying in Paris, he returned to Mexico as an assistant professor at UNAM and set up a graduate program in chemical engineering.
In 1968 he left for the US, gaining his PhD in physical chemistry at the University of California, Berkeley in 1972. He stayed on for a year at Berkeley before joining Rowland’s group at the UC Irvine as a post-doctorate fellow. Rowland was interested in ‘hot’ atoms (those with excess energy) and asked Molina to investigate what happened to CFCs. Within three months the pair had their answer – CFC gases rise into the stratosphere, where solar radiation breaks them into their component elements of chlorine, fl uorine, and carbon. Each chlorine atom is capable of destroying about 100,000 ozone molecules before becoming inactive. Their fi ndings were published in the scientific journal Nature in 1974, causing much debate until they were vindicated by the discovery of the hole in the ozone layer over Antarctica in the 1980s.
In 1975, Molina joined the faculty at Irvine, working with his wife Luisa (they married in 1973 and have a son, born in 1977). Molina felt restricted by his academic duties, however, and in 1982 he left the university to join the Jet Propulsion Laboratory at the California Institute of Technology, where he deduced that the Antarctic ozone hole was caused by ice crystals in the air amplifying the chlorine reaction. In 1989, he moved to MIT but returned to California in 2005, joining UC San Diego, and also to Mexico City, where he set up a centre for studies in energy and environment – the city’s air is much cleaner as a result. He and Luisa parted and in 2006 Molina wed Guadalupe Alvarez. He is a member of the US President’s Committee of Advisors in Science and Technology.
This text and the picture of the Nobel Laureate were taken from the book: "NOBELS. Nobel Laureates photographed by Peter Badge" (WILEY-VCH, 2008).
Picture: © Peter Badge/ Foundation Lindau Nobelprizewinners Meetings at Lake Constance |