MEASUREMENTS OF STRATOSPHERIC NO2 BY THE IMPROVED STRATOSPHERIC AND MESOSPHERIC SOUNDER

Limb sounding measurements of infra-red emission at 6.2 mum from the E arth's atmosphere have been made by the Improved Stratospheric and Mes ospheric Sounder (ISAMS). This provides a pressure modulated gas-corre lation signal and a wideband signal from which NO2 and aerosol extinct ion at 6.2 mum are jointly retrieved between 100 mb and 0.3 mb. The re trieval scheme is discussed with reference to NO2 and a qualitative co mparison made with LIMS data. The ISAMS Northern hemisphere NO2 data f or January 9th 1992 are then examined and the importance of dynamical factors highlighted.