Mario Molina

Molina at the 2011 Nobel Laurate Globalsymposium

Molina was born in Mexico City to Roberto Molina Pasquel, a lawyer and judge who went on to serve as ambassador to Ethiopia, Australia and the Philippines,[14] and Leonor Henríquez. As a child he converted a bathroom into his own little laboratory, using toy microscopes and chemistry sets. He looked up to his aunt Esther Molina, who was a chemist, and who helped him with his experiments.[15] Before deciding to become a research chemist, Mario Molina had considered the idea pursuing a musical career, in particular, becoming a violinist.[16]

After completing his basic studies in Mexico City and attending boarding school at the Institut auf dem Rosenberg in Switzerland,[14][17] he earned a bachelor's degree in chemical engineering at the National Autonomous University of Mexico (UNAM) in 1965. In 1967 he earned his postgraduate degree in polymerization kinetics at the Albert Ludwig University of Freiburg, West Germany, and in 1972 a Ph.D. in physical chemistry from the University of California, Berkeley, working with George C. Pimentel.[5][6]

Between 1974 and 2004, Molina variously held research and teaching posts at University of California, Irvine, the Jet Propulsion Laboratory at Caltech, and the Massachusetts Institute of Technology (MIT), where he held a joint appointment in the Department of Earth Atmospheric and Planetary Sciences and the Department of Chemistry.[5] On 1 July 2004, Molina joined the Department of Chemistry and Biochemistry at University of California, San Diego, and the Center for Atmospheric Sciences at the Scripps Institution of Oceanography.[18] In addition he established a non-profit organization, which opened the Mario Molina Center for Strategic Studies in Energy and the Environment (Spanish: Centro Mario Molina para Estudios Estratégicos sobre Energía y Medio Ambiente) in Mexico City in 2005. Molina served as its director.[19]

Molina served on the board of trustees for Science Service, now known as Society for Science & the Public, from 2000 to 2005.[20] He also served on the board of directors of the John D. and Catherine T. MacArthur Foundation (2004–2014),[21] and as a member of the MacArthur Foundation's Institutional Policy Committee and its Committee on Global Security and Sustainability.[22]

Molina was nominated to the Pontifical Academy of Sciences as of 24 July 2000.[23] He served as a co-chair of the Vatican workshop and co-author of the report Well Under 2 Degrees Celsius: Fast Action Policies to Protect People and the Planet from Extreme Climate Change (2017) with Veerabhadran Ramanathan and Durwood Zaelke. The report proposed 12 scalable and practical solutions which are part of a three-lever cooling strategy to mitigate climate change.[24][25]

Molina was named by U.S. President Barack Obama to form a transition team on environmental issues in 2008.[26] Under President Obama, he was a member of the United States President's Council of Advisors on Science and Technology.[27]

Molina sat on the board of directors for Xyleco.[28]

He contributed to the content of the papal encyclical Laudato Si'.[29][30][31][32]

In 2020, Mario Molina contributed to research regarding the importance of wearing face masks amid the SARS-COV-2 pandemic. The research article titled "Identifying airborne transmission as the dominant route for the spread of COVID-19" was published in the Proceedings of the National Academy of Sciences of the United States of America Journal in collaboration with Renyi Zhang, Yixin Li, Annie L. Zhang and Yuan Wang.[33]

In 1974, as a postdoctoral researcher at University of California, Irvine, Molina and F. Sherwood Rowland co-authored a paper in the journal Nature highlighting the threat of CFCs to the ozone layer in the stratosphere.[34] At the time, CFCs were widely used as chemical propellants and refrigerants. Molina and Rowland followed up the short Nature paper with a 150-page report for the United States Atomic Energy Commission (AEC), which they made available at the September 1974 meeting of the American Chemical Society in Atlantic City. This report and an ACS-organized press conference, in which they called for a complete ban on further releases of CFCs into the atmosphere, brought national attention.[35]

Rowland and Molina's findings were disputed by commercial manufacturers and chemical industry groups, and a public consensus on the need for action only began to emerge in 1976 with the publication of a review of the science by the National Academy of Sciences. Rowland and Molina's work was further supported by evidence of the long-term decrease in stratospheric ozone over Antarctica, published by Joseph C. Farman and his co-authors in Nature in 1985. Ongoing work led to the adoption of the Montreal Protocol (an agreement to cut CFC production and use) by 56 countries in 1987, and to further steps towards the worldwide elimination of CFCs from aerosol cans and refrigerators. It is for this work that Molina later shared the Nobel Prize in Chemistry in 1995 with Paul J. Crutzen and F. Sherwood Rowland.[36] The citation specifically recognized him and his co-awardees for "their work in atmospheric chemistry, particularly concerning the formation and decomposition of ozone."[37]

Molina joined the lab of Professor F. Sherwood Rowland in 1973 as a postdoctoral fellow. Here, Molina continued Rowland's pioneering research into "hot atom" chemistry, which is the study of chemical properties of atoms with excess translational energy owing to radioactive processes.[15][38]

This study soon led to research into chlorofluorocarbons (CFCs), apparently harmless gases that were used in refrigerants, aerosol sprays, and the making of plastic foams.[39] CFCs were being released by human activity and were known to be accumulating in the atmosphere. The basic scientific question Molina asked was "What is the consequence of society releasing something to the environment that wasn’t there before?"[38]

Rowland and Molina had investigated compounds similar to CFCs before. Together they developed the CFC ozone depletion theory, by combining basic scientific knowledge about the chemistry of ozone, CFCs and atmospheric conditions with computer modelling. First Molina tried to figure out how CFCs could be decomposed. At lower levels of the atmosphere, they were inert. Molina realized that if CFCs released into the atmosphere do not decay by other processes, they will continually rise to higher altitudes. Higher in the atmosphere, different conditions apply. The highest levels of the stratosphere are exposed to the sun's ultraviolet light. A thin layer of ozone floating high in the stratosphere protects lower levels of the atmosphere from that type of radiation.[39]

Molina theorized that photons from ultraviolet light, known to break down oxygen molecules, could also break down CFCs, releasing a number of products including chlorine atoms into the stratosphere. Chlorine atoms (Cl) are radicals: they have an unpaired electron and are very reactive. Chlorine atoms react easily with ozone molecules (O₃), removing one oxygen atom to leave O₂ and chlorine monoxide (ClO).[39][40]

Cl· + O
₃ → ClO· + O
₂

ClO is also a radical, which reacts with ozone to release a second O₂ molecule and a Cl atom.

ClO· + O· → Cl· + O
₂

The radical Cl atom is not consumed by this pair of reactions, so it remains in the system.[39][40]

Molina and Rowland predicted that chlorine atoms, produced by this decomposition of CFCs, would act as an ongoing catalyst for the destruction of ozone. When they calculated the amounts involved they realized that CFCs could start a seriously damaging chain reaction to the ozone layer in the stratosphere.[36][15][38]

Rowland and Molina published their findings in Nature on 28 June 1974, and also made an effort to announce their findings outside of the scientific community, informing policy makers and the news media of their work. As a result of their work, laws were established to protect the ozone layer by regulating the use of CFCs.[15][38]

Mario Molina (left) with his countryman Luis E. Miramontes, co-inventor of the first oral contraceptive, ca. 1995

Molina received numerous awards and honors,[5][6] including sharing the 1995 Nobel Prize in chemistry with Paul J. Crutzen and F. Sherwood Rowland for their discovery of the role of CFCs in ozone depletion.[1]

Molina was elected to the United States National Academy of Sciences in 1993.[41] He was elected to the United States Institute of Medicine in 1996,[42] and The National College of Mexico in 2003.[43] In 2007, he was elected to the American Philosophical Society.[44] He was also a member of the Mexican Academy of Sciences.[5] Molina was a fellow of the American Association for the Advancement of Science and co-chaired the 2014 AAAS Climate Science Panel, What We Know: The reality, risks and response to climate change.[45]

Molina won the 1987 Esselen Award of the Northeast section of the American Chemical Society, the 1988 Newcomb Cleveland Prize from the American Association for the Advancement of Science, the 1989 NASA Medal for Exceptional Scientific Advancement and the 1989 United Nations Environmental Programme Global 500 Award. In 1990, The Pew Charitable Trusts Scholars Program in Conservation and the Environment honored him as one of ten environmental scientists and awarded him a $150,000 grant.[5][46][47] In 1996, Molina received the Golden Plate Award of the American Academy of Achievement.[48] He received the 1998 Willard Gibbs Award from the Chicago Section of the American Chemical Society[49] and the 1998 American Chemical Society Prize for Creative Advances in Environment Technology and Science.[50] In 2003, Molina received the 9th Annual Heinz Award in the Environment.[51]

Asteroid 9680 Molina is named in his honor.[52]

On 8 August 2013, U.S. President Barack Obama announced Molina as a recipient of the Presidential Medal of Freedom,[53] saying in the press release:

"Mario Molina is a visionary chemist and environmental scientist. Born in Mexico, Dr. Molina came to [The United States] to pursue his graduate degree. He later earned the Nobel Prize in Chemistry for discovering how chlorofluorocarbons deplete the ozone layer. Dr. Molina is a professor at the University of California, San Diego; Director of the Mario Molina Center for Energy and Environment; and a member of the President’s Council of Advisors on Science and Technology."[4]

Molina was one of twenty-two Nobel Laureates who signed the third Humanist Manifesto in 2003.[54]

Mario Molina is the recipient of the Lifetime Achievement Award (Champions of the Earth) in 2014.[55]

Molina married fellow chemist Luisa Y. Tan in July 1973. They had met each other when Molina was pursuing his PhD at the University of California, Berkeley. They moved to Irvine, California in the fall of that year.[66] The couple divorced in 2005.[67] Luisa Tan Molina is now the lead scientist of the Molina Center for Strategic Studies in Energy and the Environment in La Jolla, California.[68] Their son, Felipe Jose Molina, was born in 1977.[14][69] Molina married his second wife, Guadalupe Álvarez, in February 2006.[14]

Molina died on 7 October 2020, aged 77, due to a heart attack.[13][67]

• Molina, Luisa T., Molina, Mario J. and Renyi Zhang. "Laboratory Investigation of Organic Aerosol Formation from Aromatic Hydrocarbons", Massachusetts Institute of Technology (MIT), United States Department of Energy, (August 2006).
• Molina, Luisa T., Molina, Mario J., et al. "Characterization of Fine Particulate Matter (PM) and Secondary PM Precursor Gases in the Mexico City Metropolitan Area", Massachusetts Institute of Technology (MIT), United States Department of Energy, (October 2008).

• Centro Mario Molina (in Spanish)
• Center for Oral History. "Mario J. Molina". Science History Institute.
• Caruso, David J.; Roberts, Jody A. (7 May 2013). Mario J. Molina, Transcript of an Interview Conducted by David J. Caruso and Jody A. Roberts at The Mario Molina Center, Mexico City, Mexico, on 6 and 7 May 2013 (PDF). Philadelphia, PA: Chemical Heritage Foundation.
• Mario Molina on Nobelprize.org including the Nobel Lecture on 8 December 1995 "Polar Ozone Depletion"
• Oral history interview with Mario J. Molina in Science History Institute Digital Collections