Ground map used for the model in a 100 km radius around the instrument (red cross). The emissions are shown in yellow (we can note the small patch of Skibotn just North–West from the instrument and the larger area covered by Tromsø further away). Superposed are the lines of constant altitudes at 200 m (yellow) and 500 m (orange) above sea level. These are the altitudes used for the albedo definition.