The absorption cross-sections of both O2, from 200 to 220 nm, and O3 from 220 to 235 nm have been deduced from measurements of the atmospheric absorption performed at night aboard a stratospheric balloon launched from Aire sur l'Adour (France).

The ozone column content was previously determined using the absorption measured from 278 to 289 nm, assuming that the ozone absorption cross sections are well known in this wavelength interval. The O2 and O3 cross sections have been found to meet most of the laboratory measurements. From 200 to 210 nm the results concerning the O2 cross-sections do not confirm the low values measured recently in the stratosphere and in the laboratory.