Space-Based Constraints on North American Emissions of Nitrogen Oxides

Abstract

Global emission inventories of nitrogen oxides (NOx) remain uncertain to a factor of 2 with substantial implications for understanding of surface air quality, atmospheric oxidation, and climate. We will discuss recent progress in improving NOx emission inventories by combining traditional bottom-up inventories with top-down constraints from the GOME and SCIAMACHY satellite instruments. This integration results in an optimized surface NOx emission inventory with lower uncertainties. Additionally, comparisons with in-situ NO2 profile measurements during the ICARTT campaign (summer 2004) will be shown to establish the validity and quantify the accuracy of the SCIAMACHY tropospheric NO2 column abundances.