The College of Science and the Flatley Center for Undergraduate Scholarly Engagement are pleased to invite you to a keynote lecture by Dr. Joseph Francisco, President's Distinguished Professor and Professor of Chemistry at the University of Pennsylvania, who will present his talk, A Fresh Look at the Chemistry Behind Acid Rain. 

The two major components of acid rain are sulfuric acid (H2SO4) and nitric acid (HNO3). Sulfur dioxide (SO2) is the main precursor of H2SO4. Atmospheric sulfur dioxide is oxidized homogeneously by reaction of SO2 with OH and O2 leading to SO3, which then reacts with water to form sulfuric acid. This is the now accepted acid rain mechanism for generation of atmospheric sulfuric acid. In this talk we will review the traditional acid rain mechanism and we will introduce a new acid rain mechanism that relies on the photochemistry of SO2 and show how this new chemistry can be an important new ingredient in fully understanding how acid rain is formed, but not yet considered by current atmospheric models. Why is this important? Sulfur dioxide has been proposed in solar geoengineering as a precursor of H2SO4 aerosol, a cooling agent active in the stratosphere to contrast climate change dur to the anthropogenic emissions of greenhouse carbon dioxide. Considering the introduction of SO2 in the stratosphere, the photochemistry of this new chemistry is critical to assessing whether strategies to mitigate climate change is feasible by injection of SO2.

Dr. Francisco is focused on bringing new tools from experimental physical and theoretical chemistry to atmospheric chemical problems to enhance our understanding of chemistry in the atmosphere at the molecular level. This work has led to important discoveries of new chemistries occurring on the interfaces of cloud surfaces as well as fundamental new chemical bonding controlling these processes. His current work is investigating how solar radiation impacts chemistry on clouds interfaces. He also has research collaborations that are investigating the detail atmospheric chemistry of acid rain. He received his Ph.D. from Massachusetts Institute of Technology, and was a Research Fellow at University of Cambridge in England, and a Visiting Associate in Planetary Science at the California Institute of Technology. He currently serves as Executive and Associate Editor of the the Journal of the American Chemical Society and on the Editorial Board of the Proceedings on the National Academy of Sciences. He is a past-president of the American Chemical Society.

This event is part of FURF, the College of Science's Fall Undergraduate Research Fair. All are welcome to attend. Admission is free.

 

 

Originally published at science.nd.edu.