“Standard” atmosphere used in the to model calculation (see text): upper left: the pressure profile, upper right: the temperature profile, lower left, from the right to left, the N₂ (blue), O₂ (green) and O₃ (pink) mixing ratios as a function of altitude (km), lower right, from bottom to top, the O₂ (green) molecular bands and Rayleigh, N₂ (blue) Rayleigh, and O₃ (pink) cross sections as a function of wavelength (in nm).