Seminar

Abstract

Uncertainties in NH₃ emissions pose challenges to air quality modeling, development of pollution control strategies, and understanding the global transport pathways of reactive nitrogen. This talk will present results of inverse modeling of NH₃ emissions using new remote sensing observations from TES. First, collaborative work is presented which assess the ability of remote sensing to capture spatial trends and absolute concentrations of surface level NH₃. Capabilities and limitations for constraining NH₃ emissions with this data are assessed via inverse modeling tests using pseudo observations (generated by the model). An adjoint-based inverse model is then applied over North America using real observations from the year 2008. The resulting constraints on NH₃ inventories are evaluated through cross validation with independent data sets and qualified with calculation of uncertainty reductions. Benefits of accomplishing these goals are to further our overall knowledge of the environmental impacts of NH₃ emissions by affording better estimates of incidents of excessively harmful PM2.5 levels using air quality models as well as reducing uncertainty in quantifying the sources and fate of ecologically disruptive levels of reactive nitrogen.