H₂O telluric absorption lines affecting absorption lines associated with the z = 2.42743 DLA in the UVES spectrum of GRB080310. The telluric lines – modelled by molecfit – are shaded in yellow; the models for the different components (a,b,c,d) of the absorption system are represented with different colours (blue, cyan, green, orange), while the combined model is in red. See De Cia et al. (2012) for details.