This data set is the main result of an ESA-funded study entitled 'Measurement of H2O Absorption Cross-Sections for the Exploitation of GOME'. The GOME instruments are downward-viewing satellite-borne spectrometers. Vertical profiles of atmospheric chemical species (in particular ozone) can be determined from the observations. Water vapour is of particular significance because it dominates the energy balance of the atmosphere. Also the spectrum of water vapour must be adequately understood and accounted for when deriving the concentration or distribution of trace atmospheric species. This dataset is public.