Preliminary control of model background properties: aerosol optical cross-sections and atmosphere temperature profiles Left: extinction (upper curves) and scattering (lower curves) cross-sections for an aggregate of 3000 monomers of radius 50 nm with a fractal dimension D_f = 2, computed with the mean field approximation model (Botet et al. 1997; Rannou et al. 1997) and with the model used by Tomasko et al. (2008). Right: temperature profile as a function of pressure observed with HASI (Fulchignoni et al. 2005) and profiles based on HASI with a temperature shift ±∆T (red dots). We also plotted the temperature profiles after CIRS observations (Vinatier et al. 2015; Mathé et al. 2020) that best correspond to the dates and the latitudes of the occul-tations treated in this work (Table 1). The thick black dashed line shows the temperature profile retrieved by Schinder et al. (2020) with radio-occultation measurements during the flyby T52E (4 April 2009 at lat = 12°S).