Brent Riffel is currently a Masters student in the Hydrogen Pathways program and his research interests include the study of criteria pollutant and greenhouse gas emissions associated with energy consumption and transportation.  He is interested in studying the energy and emissions-related issues of a hydrogen based US economy as compared to the current fossil fuel economy.  Currently he is investigating the climate forcing implications for changes in NO_x emissions (see description under Environmental Analysis Research Track).   Brent has a B.A. in Chemistry from Pomona College and has a background in atmospheric chemistry.  He spent one year at the NASA Ames Research Center investigating nitric acid/NO_x cycling via aerosol chemistry.