Scientific objective 2: Stratospheric and mesospheric chemistry and transport

The tests and improvements for models of stratospheric and mesospheric chemistry and transport are discussed. The structure of the stratosphere and mesosphere, in terms of chemistry and dynamics, is reviewed. Current satellite experiments for long duration observation, focused on the measurement of aerosols and gases involved in the ozone-nitrogen chemistry of the stratosphere, are discussed. Future satellite experiments and Shuttle lidar contributions are proposed.