Twilight rocket measurements of high-latitude atomic oxygen density during the DYANA campaign

Abstract

Listen

Translate article

During the DYANA ( DYnamics Adapted Network for the Atmosphere) campaign, a rocket containing a resonance fluorescence experiment for measurement of atomic oxygen concentrations was launched at twilight-dawn from ESRANGE, Kiruna, Sweden in March 1990. The measured atomic oxygen concentration rose very sharply near 80 km to about 10 11 atoms cm −3, achieved a peak value of 3 × 10 11 atoms cm −3 between 90 to 105 km, and decreased with increasing rocket altitude to about 155 km where the instrument's noise level was reached. In addition, ground-based, near-infrared radiometric and spectral measurements of the mesospheric and lower thermospheric hydroxyl (OH) airglow emissions were also obtained during the night up to the time of rocket launch. We have used least-squares spectral fitting procedures to obtain the OH Meinel (3-1) band intensities and accurate ( ± 2.5K) rotational temperatures from individual scans. The band intensities show considerable structure throughout the night, dropping sharply by about a factor of 3 during sunrise when the rocket was launched. The rotational temperatures were consistently around 225 K throughout the night and during the rocket flight. During the MAP/WINE campaign in February 1984, similar measurements using identical rocket-borne and ground-based techniques were made at night from ESRANGE. In this paper, the DYANA and MAP/WINE measurements are inter-compared and discussed and further compared with model calculations.