Anisotropy of small-scale stratospheric irregularities retrieved from scintillations of a double star α-Cru observed by GOMOS/ENVISAT

V. Kan (1) , Viktoria F. Sofieva (2) , Francis Dalaudier (3)

1 IAP - A.M.Obukhov Institute of Atmospheric Physics
2 FMI - Finnish Meteorological Institute
3 STRATO - LATMOS

In this paper, we discuss estimating anisotropy of air density irregularities (ratio of characteristic horizontal and vertical scales) from satellite observations of bi-chromatic scintillations of a double star whose components are not resolved by the detector. The analysis is based on fitting experimental auto- and cross-spectra of scintillations by those computed using the 3-D spectral model of atmospheric irregularities consisting of anisotropic and isotropic components. Application of the developed method to the scintillation measurements of the double star α-Cru by GOMOS (Global Ozone Monitoring by Occultation of Stars) fast photometers results in estimates of anisotropy coefficient of ~15-20 at altitudes 30-38 km, as well as other parameters of atmospheric irregularities. The obtained estimates of the anisotropy coefficient correspond to small-scale irregularities, close to the buoyancy scale.

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]

V. Kan, Viktoria F. Sofieva, Francis Dalaudier. Anisotropy of small-scale stratospheric irregularities retrieved from scintillations of a double star α-Cru observed by GOMOS/ENVISAT. Atmospheric Measurement Techniques, 2012, 5 (11), pp.2713-2722. ⟨10.5194/amt-5-2713-2012⟩. ⟨hal-00719749⟩