Ozone Day is observed globally on September 16. On this same day in 1987, the Montreal Protocol, an international agreement to protect the ozone layer, was signed. Mario José Molina Henriquez (1943–2020) was the first to acknowledge the impact of chlorofluorocarbons (CFCs) on ozone depletion. Frank Sherwood Rowland and Mario Molina became the voices warning the world about the dangers of CFCs and ozone depletion.
Atmospheric chemist Mario Molina has dedicated his life to fighting for an international environmental strategy. Before starting his quest to promote climate change awareness and policy, he conducted ground-breaking research on the ozone layer, resulting in an international agreement to outlaw the human-made chemicals that were destroying the Earth’s shield.
Mario Molina, the Chemist
Mario Molina, born on March 19, 1943, in Mexico City, has always aspired to be a chemist. When Molina was a child, he turned one of the family toilets into a personal chemistry lab since he was captivated by the subject. His aunt Esther Molina, a chemist, encouraged and supervised the boy by assisting him in conducting more difficult experiments that are typically feasible with a child’s chemical set. Molina’s parents sent him to a boarding school in Europe because they knew he had a passion for science and believed enrolling him there would help develop his ambition. He was instrumental in determining the existence of the Antarctic ozone hole and shared the 1995 Nobel Prize in Chemistry for discovering the risk posed by chlorofluorocarbon (CFC) emissions to the ozone layer on Earth. He was the first Mexican-born scientist to win a Nobel Prize in Chemistry and the third Mexican-born recipient of a Nobel Prize.
Academic Excellence
Molina returned to Mexico City for his graduate studies, earning a Master’s degree in chemical engineering from the National Autonomous University of Mexico. To fill in the gaps in his academic background, he later studied mathematics and science at universities in France and Germany. Molina joined the University of California, Berkeley, for graduate studies. After earning his doctorate, he moved to UC Irvine, where he worked as a postdoctoral researcher on Rowland’s team. Molina and Rowland then began contemplating what might happen to CFCs released into the sky.
Field of Work
Molina worked as a researcher and professor at the University of California, Irvine, the California Institute of Technology, the Massachusetts Institute of Technology, the University of California, San Diego, and the Centre for Atmospheric Sciences at the Scripps Institution of Oceanography. Additionally, Molina served as the director of the Mexico City-based Mario Molina Centre for Energy and Environment.
Personal Life
In July 1973, Molina married Luisa Y. Tan, a fellow chemist. They met at the University of California, Berkeley While doing his PhD. They have a son, Philip Jose Molina, and the couple divorced in 2005. Luisa Tan Molina serves as the centre’s principal scientist in La Jolla, California’s Molina Centre for Strategic Studies in Energy and the Environment. In February 2006, Molina married Guadalupe Alvarez. Molina passed away after a heart attack on October 7, 2020, at 77.
Study on Chlorofluorocarbons
Molina, a postdoctoral student at the University of California, Irvine, conducted a study on Chlorofluorocarbons in 1973. Molina’s work was purely hypothetical and based on computer simulations. His findings indicated that CFCs could destroy the oxygen compound of ozone at high atmospheric pressure. According to his analysis, if CFCs manage to deplete 7% of ozone after 60 years, the planet will be in trouble. His study states that photons from ultraviolet radiation, known to dissociate oxygen molecules, could break down CFCs and release many compounds, including chlorine atoms, into the stratosphere. Chlorine atoms (Cl) are radicals as they have an unpaired electron and are highly reactive. Ozone molecules (O3) and chlorine atoms easily react, with the removal of an oxygen atom leaving chlorine monoxide (ClO) and oxygen.
The study by Molina and Roland, published in the magazine ‘Nature’ in 1974, brought attention to the threat that CFCs represent to the stratospheric ozone layer. CFCs were widely used at the time as refrigerants and chemical propellants. This study garnered a lot of attention as it called for a complete ban on the release of further CFCs into the atmosphere, along with a news conference organised by the American Chemical Society.
Adoption Of the Montreal Protocol
Commercial manufacturers and chemical industry organisations disagreed with Rowland and Molina’s conclusions, and it took until 1976, when the National Academy of Sciences published an assessment of the science, for the public to start to agree that action was required. Evidence of the long-term drop in stratospheric ozone above Antarctica, which was published by Joseph C. Farman and his co-authors in ‘Nature’ in 1985, provided additional support for Rowland and Molina’s research. The adoption of the Montreal Protocol was the result of ongoing work.
By using, this procedure, the number of CFCs released into the atmosphere significantly decreased, which slowed climate change and controlled the rate of ozone depletion. Molina later shared the 1995 Nobel Prize in Chemistry with Paul J. Crutzen and F. Sherwood Rowland for this work.
According to climate estimates, the ozone layer will have recovered to its 1980 levels by 2040 (for the bulk of the earth) and 2066 (over Antarctica). The Montreal Protocol is praised as an example of successful international cooperation due to its widespread implementation.
A Research Team Under His Leadership
Following this, Mario Molina headed a study team to look into the causes of the rapid ozone depletion in Antarctica in 1985 after Joseph Farman found a hole in the ozone layer there. It has been discovered that Antarctica’s stratospheric conditions are perfect for chlorine activation, which ultimately results in ozone depletion.
Research on the Chemistry of Air Pollution
Mario Molina conducted interdisciplinary research on the chemistry of air pollution in the lower atmosphere and worked with experts to address the deteriorating air quality in metropolitan areas, making a significant contribution to Mexico’s understanding of the problem and potential solutions in the city’s Metropolitan areas.
Study On Face Masks
During the SARS-COV-2 pandemic in 2020, Mario Molina contributed to the body of knowledge addressing the value of using face masks. With the assistance of Renyi Zhang, Yixin Li, Annie L. Zhang, and Yuan Wang, a study titled “Identifying airborne transmission as the dominant route for the spread of Covid-19” was published in the Journal, ‘Proceedings of the National Academy of Sciences’.
Nobel Prize
In 1995, Molina shared the chemistry Nobel Prize with Paul J. Crutzen and F. Sherwood Rowland for their research into the connection between CFCs and ozone depletion. He was elected to the United States National Academy of Sciences in 1993, the United States Institute of Medicine in 1996 and The National College of Mexico in 2003. Molina was a member of the Mexican Academy of Sciences and was elected to the American Philosophical Society in 2007. Molina was a fellow of the American Association for the Advancement of Science and co-chaired the 2014 AAAS Climate Science Panel.
Recognitions
Molina received numerous honours, including the 1989 NASA Medal for Exceptional Scientific Advancement, the 1987 Esselen Award from the Northeast Division of the American Chemical Society, the 1988 Newcomb Cleveland Prize from the American Association for the Advancement of Science, and the 1989 United Nations Environmental Programme Global 500 Award.
He received a $150,000 scholarship in 1990 as part of The Pew Charitable Trusts Scholars Programme in Conservation and the Environment honouring him as one of ten environmental experts. Molina was given the American Academy of Achievement’s Golden Plate Award in 1996. He was given the 1998 Willard Gibbs Award and the 1998 American Chemical Society Prize for Creative Advances in Environment Technology and Science by the Chicago Chapter of the American Chemical Society, respectively. Molina won the 9th Annual Heinz Award in the Environment in 2003.
For his accomplishments, he was awarded the Presidential Medal of Freedom, the Tyler Prize for Environmental Achievement in 1983, the UNEP-Sasakawa Environment Prize in 1995, the United Nations Champion of the Earth Award, and more than 40 honorary degrees.
Professor Molina has dedicated most of his professional career to advancing global collaboration for rapid economic growth and sustainable development. In his later works, he put a lot of emphasis on concerns related to development and air quality. The air quality in Mexico City is a concern for his centre there, whereas his lab in San Diego focuses on the chemical properties of atmospheric particles.
Credits and Reference
https://sciencehistory.org/education/scientific-biographies/mario-molina/