Tropical tropospheric ozone columns from nadir satellite retrievals using the Convective Cloud Differential technique on GOME, SCIAMACHY and GOME-2 data

Tropospheric ozone (O3) is one of the most important atmospheric pollutants close to surface. Remote sensing from satellites can provide consistent information of total ozone concentrations over large areas. By removing the stratospheric contributions using the Convective differential technique (CCD) on GOME/ERS-2 (1995- 2003), SCIAMACHY/Envisat (2002-2012), and GOME-2/MetOpA (2007-today) total O3 and cloud data it is feasible to estimate monthly mean tropospheric ozone columns over the tropics. The focus of this thesis was to create an improved CCD-IUP algorithm and to study variability and trends of the unique long-term record (1996-2015) on a regional and tropical scale. A detailed uncertainty analysis of the CCD-IUP algorithm has been performed along with a study upon the trend uncertainties from merging the datasets. Finally, the influence of ENSO on tropospheric ozone and the origin of its anomalies due to dynamics or emissions was investigated.