Atmospheric Measurement Techniques

Abstract. Satellite observations of nitrogen dioxide (NO2) provide valuable information on both stratospheric and tro-pospheric composition. Nadir measurements from GOME, SCIAMACHY, OMI, and GOME-2 have been used in many studies on tropospheric NO2 burdens, the importance of dif-ferent NOx emissions sources and their change over time. The observations made by the three GOME-2 instruments will extend the existing data set by more than a decade, and a high quality of the data as well as their good consistency with existing time series is of particular importance. In this paper, an improved GOME-2 NO2 retrieval is de-scribed which reduces the scatter of the individual NO2 columns globally but in particular in the region of the South-ern Atlantic Anomaly. This is achieved by using a larger fitting window including more spectral points, and by ap