The production and use of biofuels or fossil fuels release differing amounts of air pollutants in different geographic locations at different times with associated ecological and human health effects that impose costs on society. Professor Julian D. Marshall (Civil Engineering, Institute on the Environment) and his group are using MSI to study the emissions tradeoffs between using biofuels and fossil fuels. His group uses the supercomputers to run state-of-the-science meteorological, emissions, and air-quality models. This research appears in the 2011 Annual Research Highlights. This image shows a map of annual average gridded emissions of oxides of nitrogen for the production and use of ethanol from a mix of corn and corn stover; temporal profiles are included to show variation by month of year, day of week, and hour of day.