Professor Jennifer Murphy

Professor Jennifer Murphy
Department of Chemistry
University of Toronto

Living in the age of ammonia

Many of us are familiar with the Haber-Bosch process as part of the general chemistry canon, and looking forward, ammonia is being promoted as a key energy carrier in decarbonization strategies. Beyond supporting food production for half the world’s population, more than a century of synthetic ammonia production has profoundly changed the way nitrogen cycles among the environmental compartments on Earth. As a water-soluble alkaline molecule, atmospheric concentrations of ammonia exhibit dramatic variability in space and time, challenging the accuracy of many conventional approaches in analytical chemistry. Ammonia now constitutes the dominant multiphase buffer in the atmosphere, thus regulating the acidity of aerosol and cloud water, with consequences for the solubility and reactivity of metals, organics, and halogens. While typically considered unreactive in the gas phase, the oxidation of ammonia leads to secondary production of nitrous oxide, with consequences for climate and ozone depletion. In this talk, I will share examples from our research into the sources, impacts and fate of ammonia in the atmosphere.

Jennifer Murphy

Jennifer Murphy is a Professor in the Department of Chemistry at the University of Toronto, where she teaches and mentors a team of researchers who focus mainly on understanding the sources and fates of atmospheric pollutants and greenhouse gases. Her team has performed fieldwork across Ontario and in California, Utah, Colorado, northern Michigan, the Alberta oil sands region, and the Canadian Arctic. They deploy scientific instruments at ground sites, on tall towers, stratospheric balloons, aircraft and ships to measure chemicals in the atmosphere. In addition, they leverage government monitoring datasets to characterize spatial and temporal trends in air pollution and the roles of emissions and meteorology. She served as a member of the Scientific Steering Committee of International Global Atmospheric Chemistry (IGAC) project from 2016 to 2020, and as an Associate Editor at Journal of Geophysical Research - Atmospheres since 2020. In 2019, she was the recipient of an American Geophysical Union Ascent Award for mid-career excellence in atmospheric science. In 2020, she was a member of the team that won the Brockhouse Canada Prize for Interdisciplinary Research in Science and Engineering, and in 2024 she received the Canadian Society of Chemistry’s Clara Benson Award. Jennifer completed her BSc at McGill University (2000) in Chemistry and a minor in Environmental Studies. During her PhD in Chemistry at the University of California Berkeley (2005), she tracked the sources of air pollution influencing the deposition of nutrients to Lake Tahoe and studied smog in central California. As a postdoctoral fellow at the University of East Anglia (2006), she operated a mass spectrometer aboard a research aircraft flying over West Africa to measure volatile organic compounds emitted from tropical forests.

Hosted by Professor Hannah Kenagy