Airborne measurements during the European Arctic Stratospheric Ozone Experiment column amounts of HNO₃ and O₃ derived from FTIR emission sounding

During the EASOE (European Arctic Stratospheric Ozone Experiment) winter campaign 1991/92, first measurements were made from an aircraft with the new atmospheric sounder MIPAS‐FT (Michelson Interferometer for Passive Atmospheric Sounding ‐ Flugzeug Transall). The instrument measures infrared radiation emitted by atmospheric trace constituents in the spectral range between 750 and 1250 cm −1 . As first results, we present zenith column amounts of O 3 and HNO 3 retrieved from data recorded between January 30 and February 16, 1992 in the region from 45° west to 45° east and from 55° to 80° north. The column amounts vary considerably, from 1 to 3 × 10 16 molecules/cm² for HNO 3 and from 180 to 420 DU for O 3 , respectively. The strong linear correlation between these stratospheric gases indicates that the large variations during that period are mainly due to dynamic processes in the arctic atmosphere.