Resonant lidar detection of Ca and Ca⁺ in the upper atmosphere

Claire Granier (1) , Jean-Pierre Jégou (1) , Gérard Mégie (1)

1 SA - Service d'aéronomie

Resonant lidar detection of neutral (Ca-423 nm) and ionized ( Ca⁺ - 393 nm) calcium altitude distributions has been performed during nighttime at the Observatoire de Haute-Provence. The emitter is composed of two Nd-Yag pumped dye lasers, the 393 nm emission being obtained by three waves mixing in a non-linear crystal. The first detection of Ca has been carried out in December, 1982 and has shown that the integrated abundance of the atomic form is low, with a value of about 1.5 × 10⁷ cm-2, further confirmed by measurement performed in July, 1983. During this same month, the detection of Ca+ has been achieved, proving the lidar ability to follow rapid evolutions of Ca+ layers, which appear between 85 and 115 km altitudes.

Keywords: Atmospheric Composition; Calcium; Optical Radar; Radar Detection; Upper Atmosphere; Crystal Optics; Dye Lasers; Nonlinear Optics; Positive Ions; Vertical Distribution; Geophysics; Atmospheric Composition and Structure: General or miscellaneous

Domains: Atmospheric and Oceanic Physics [physics.ao-ph]; Ocean, Atmosphere

Claire Granier, Jean-Pierre Jégou, Gérard Mégie. Resonant lidar detection of Ca and Ca⁺ in the upper atmosphere. Geophysical Research Letters, 1985, 12 (10), pp.655-658. ⟨10.1029/GL012i010p00655⟩. ⟨insu-03590493⟩