A new numerical model of the middle atmosphere 2. Ozone and related species

A new two-dimensional model with detailed photochemistry is presented. The model includes a detailed description of photochemical processes in the stratosphere and mesosphere. The downward transport of H₂, H₂O, and NO_y from the mesosphere to the stratosphere is examined, and it is shown that mesospheric processes can influence the distributions of these chemical species in polar regions. For HNO₃ we also find that small concentrations of liquid aerosols above 30 km could play a major role in determining the abundance in polar winter at high latitudes. -from Authors