Assessing effects of rate parameter changes on ozone models using sensitivity analysis

Effects of recommended rate parameter changes in the NASA JPL-2000 evaluati on from JPL-94 values on local ozone concentrations in a 2-D model are pred icted using local sensitivity analysis results from the LLNL 2-D diurnally averaged model. Ozone decreases of 5% in the middle stratosphere and 10% in creases near the tropopause and upper troposphere are indicated. Altered NO , kinetics are largely responsible for these changes, and increased model N O, levels and ozone depletion from stratospheric aircraft are also expected according to sensitivity analysis. Effects of specific changes, such as th e nitric acid formation rate, are examined. New error bars on rate paramete rs in the evaluation are propagated by the sensitivity coefficients to deri ve revised kinetics uncertainties for the model ozone calculations at sever al altitudes, latitudes, and seasons. Middle-upper stratospheric ozone unce rtainties of 12% from the catalytic photochemistry are indicated, increasin g in the lower stratosphere.