In Situ Trace Gas and Particle Measurements in the Summer Lower Stratosphere During STREAM II: Implications for O sub(3) Production

Data on lower stratospheric concentrations of nitric acid, carbon monoxide, ozone, and particle number are presented, which were measured as part of the Stratosphere Troposphere Experiment by Aircraft Measurements (STREAM) II project. The summer mission included five flights from an airport in the Netherlands, at different altitudes up to 12.5 km. A chemistry trajectory model and a global three-dimensional chemistry-transport model were then used to assess the importance of HNO sub(3) and CO in O sub(3) production and the possible role of aircraft nitrogen oxides emissions. The extensive data are tabulated. Ozone was found to be strongly correlated with HNO sub(3), and the ratio of HNO sub(3)/O sub(3) remained fairly constant. Modeling results indicated that, under these chemically perturbed conditions, the O sub(3) production in molecules per added NO sub(x) molecule is smaller than previously assumed for subsonic commercial aircraft emissions at cruise altitude.