Rate parameter uncertainty effects in assessing stratospheric ozone depletion by supersonic aviation

Box model sensitivity‐uncertainty calculations for O 3 depletion from supersonic aircraft emissions were performed at the most perturbed locale using localized outputs of the LLNL 2‐D diurnally averaged assessment model. Processes controlling N 2 O 5 , catalytic O 3 loss steps O+NO 2 and HO 2 +O 3 , HOx sink reactions OH+ HNO 3 /HNO 4 , and the O+O 2 recombination that forms O 3 are identified as the dominant photochemical uncertainty sources. Guided by local sensitivities, 2‐D model runs were repeated with 9 targeted input parameters altered to 1/3 of their l‐σ uncertainties to put error‐bounds on the predicted O 3 change. Results indicate these kinetic errors can cause the predicted local O 3 loss of 1.5% to be uncertain by up to 3% in regions of large aircraft NOx injection.