On the inversion of O sup + ( sup 2 D minus sup 2 P) 7320 Angstrom twilight airglow observations: A method for recovering both the ionization frequency and the thermospheric oxygen atom densities

Journal Article · Tue Jan 01 04:00:00 EST 1991 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/90JA01995· OSTI ID:5312987

McDade, I C; Sharp, W E ^[1]; Richards, P G; Torr, D G ^[2]

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1. Univ. of Michigan, Ann Arbor (USA)
2. Univ. of Alabama, Huntsville (USA)

In this paper, the authors demonstrate that it is possible to invert twilight observations of the O{sup +}({sup 2}D{minus}{sup 2}P){minus}7320 {Angstrom} airglow emission to obtain information about both the thermospheric atomic oxygen densities and the unattenuated O{sup +}({sup 2}P) ionization frequency. The efficacy of the proposed approach, which relies upon making twilight observations in more than one viewing direction, is illustrated using a synthetic data set and an inversion algorithm based on a simple photochemical model. The results of this study show that day-to-day variations in the thermospheric oxygen atom densities may be monitored from the ground without requiring complementary measurements of the solar EUV flux. The study also shows that twilight observations may be used to monitor variations in the solar flux components that are responsible for O{sup +}({sup 2}P) production and EUV heating of the upper thermosphere.

• OSTI ID: 5312987
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 96:A1; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640200 -- Atmospheric Physics
640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AIRGLOW
ALGORITHMS
ATMOSPHERIC CHEMISTRY
CHEMICAL COMPOSITION
CHEMISTRY
DENSITY
EARTH ATMOSPHERE
ELEMENTS
EMISSION SPECTRA
IONIZATION
MATHEMATICAL LOGIC
MATHEMATICAL MODELS
NONMETALS
OXYGEN
PHOTOCHEMISTRY
PHYSICAL PROPERTIES
RADIATIONS
SOLAR RADIATION
SPECTRA
STELLAR RADIATION
THERMOSPHERE
VARIATIONS