AGS-PRF: Constraining Ammonia Emission Sources in Urban Areas Utilizing Nitrogen Stable Isotopes

Walters Wendell W, Lafayette IN

Investigators

Abstract

Ammonia emissions that produce and neutralize aerosols are increasing in the US . While the agricultural ammonia sources from fertilizer use dominate and are well studied, field studies show that ammonia produced from fossil fuel use in urban areas is underrepresented in current models. This may be a result of the use of various catalytic NOx scrubber technologies in vehicles and power-plants to reduce air pollution that can increase ammonia production, particularly in urban areas. The proposal will use isotope specific ammonia measurements to quantify the fossil fuel related sources in Rhode Island, Indianapolis and Philadelphia. The results will help determine how fossil energy use and and pollution abatement technologies are affecting urban ammonia sources and human health. The research will use isotopic (15N/14N) studies to develop fingerprinting tools for fossil ammonia sources from automobile engines, power plants, and catalytic NOx scrubbers, agricultural and oceanic sources. Field studies in Providence, Indianapolis, and Rhode Island will be performed to quantitatively attribute the ammonia sources using the 15N/14N observations of ammonia. State of the art instrumentation will be used for the measurements and the results will resolve the outstanding debate on how much fossil combustion is contributing to the ammonia budget and how catalytic NOx scrubber technologies are affecting them.