Atmospheric NO from space: the SCIAMACHY capabilities

The SCanning Imaging Absorption spectroMeter for Atmospheric ChartograpHY (SCIAMACHY) has been proposed in 1988 as a payload of the ESA earth observation satellite ENVISAT 1, which is scheduled for launch in 2001 for a four-year mission. SCIAMACHY operates in eight channels covering the UV, the visible and two infrared regions. Recent developments in the testing of the instrument now enable not only the full use of channel 1 (240 nm–314 nm) at a required high level of performance but in some special cases its extension to 220 nm. This instrumental improvement allows new objectives to be addressed in the upper stratoosphere, on top of the already proposed mesospheric and thermospheric investigations of nitric oxide. Simulations show the instrument capabilities for these studies. These NO observations will be performed in solar occultation, lunar occultation and nadir. Previous NO results are reviewed with an emphasis on results obtained by the infrared solar occultation technique as exemplified by the SPACELAB grille spectrometer and other instruments. The capabilities of SCIAMACHY for mapping the total column of upper atmospheric NO is investigated as well as possibilities to infer NO vertical distribution and transfer properties between the different atmospheric regions.