Analysis of stratospheric NO2 trends above Jungfraujoch using ground-based UV-visible, FTIR, and satellite nadir observations

The trend in stratospheric NO2 column at the NDACC (Network for the Detection of Atmospheric Com- position Change) station of Jungfraujoch (46.5 N, 8.0 E) is assessed using ground-based FTIR and zenith-scattered visible sunlight SAOZ measurements over the period 1990 to 2009 as well as a composite satellite nadir data set con- structed from ERS-2/GOME, ENVISAT/SCIAMACHY, and METOP-A/GOME-2 observations over the 1996-2009 pe- riod. To calculate the trends, a linear least squares regres- sion model including explanatory variables for a linear trend, the mean annual cycle, the quasi-biennial oscillation (QBO), solar activity, and stratospheric aerosol loading is used. For the 1990-2009 period, statistically indistinguishable trends of 3.7± 1.1 % decade 1 and 3.6± 0.9 % decade 1 are