Physical Sciences and Mathematics Commons^™

Sources And Chemistry Of Noₓ In The Upper Troposphere Over The United States, Lyatt Jaegle, Daniel J. Jacob, Yuhua Wang, Andrew J. Weinheimer, Brian A. Ridley, Teresa L. Campos, Glen W. Sachse, Donald E. Hagen

Physics Faculty Research & Creative Works

The origin of NO_x in the upper troposphere over the central United States is examined using aircraft observations obtained during the SUCCESS campaign in April–May of 1996. Correlations between NO_y (sum of NO_x and its oxidation products) and CO at 8–12 km altitude indicate that NO_x originates primarily from convective transport of polluted boundary layer air. Lightning and aircraft emissions appear to be only minor sources of NO_x. Chemical steady state model calculations constrained by local observations of NO underestimate the measured NO_x/NO_y concentration ratio at 8–12 km altitude by a …