Satellite detection and model verification of NO x emissions from power plants in Northern China

We evaluate the recently increasing tropospheric NO 2 columns in Northern China measured by the Ozone Monitoring Instrument (OMI) with an advanced power-plant NO x emission inventory and the NASA INTEX-B emission inventory, using a global chemical transport model (GEOS-Chem). In areas with newly built power plants the modeled and OMI-retrieved summertime average tropospheric NO 2 columns increased by 55% and 47%, respectively, between 2005 and 2007. A monthly average increase of 1.79 Gg NO x emissions is calculated to lead to an increase of 1.0 × 10 15 molecules cm − 2 in the modeled NO 2 columns in the study areas. Good consistency ( R 2 = 0.61, slope = 1.18, n = 14) between the increased modeled and OMI-retrieved summertime average NO 2 columns is found. These results suggest that NO x emissions from large power plants in Northern China can be identified and quantified using OMI retrievals with confidence. The NASA INTEX-B emission inventory appears to underestimate the NO x emissions from the industry and transportation sectors, making it more difficult to quantify power-plant emissions when they are co-located with large cities.