Multiple Airglow Chemistry approach for atomic oxygen retrievals on the basis of in situ nightglow emissions

Electronically excited states of molecular and atomic oxygen (O(2 )and O) are coupled with each other as well as with the ground states of O-2 and O in the Multiple Airglow Chemistry (MAC) model representing the oxygen airglow and the oxygen photochemistry in the upper Mesosphere and Lower Thermosphere region. The MAC model couples seven O-2 and three O states and was developed on the basis of in situ measurements from the ETON (Energy Transfer in the Oxygen Nightglow) campaign employed to tune rate values of unknown or poorly constrained processes. The same rate values are applied in the MAC model verified and validated on the basis of the in situ measurements obtained during the WADIS-2 (WAve propagation and DISsipation in the middle atmosphere), the WAVE2000 (WAVes in airglow structures Experiment, 2000) and WAVE2004 campaigns. Data sets measured using devices aboard the WADIS-2 rocket are considered to be self-consistent because the MAC retrievals of a concentration profile of O in the ground state ([O(P-3)]) can be based on these data sets only. The measuring sites of the in situ data sets from the WAVE2000 and WAVE2004 campaigns are collocated with those of remotely obtained data sets, and these data sets are combined for the MAC retrievals. O-2 precursors responsible for the oxygen green line emission, emissions in the Atmospheric band and the Infrared Atmospheric band are identified and confirmed by calculations with the validated MAC model.