Intercomparison of Ground- and Satellite-Based Total Ozone Data Products at Marambio Base, Antarctic Peninsula Region

This study aims to compare the ground-based Brewer spectrophotometer total ozone column measurements with the Dobson spectrophotometer and various satellite overpass data available at Marambio Base during the period 2011-2013. This station provides a unique opportunity to study ozone variability near the edge of the southern polar vortex; therefore, many institutions, such as the National Meteorological Service of Argentina, the Finnish Meteorological Institute and the Czech Hydrometeorological Institute, have been carrying out various scientific activities there. The intercomparison was performed using total ozone column data sets retrieved from the ground-based instruments and from Ozone Monitoring Instrument (OMI)-Total Ozone Mapping Spectrometer (TOMS), OMI-Differential Optical Absorption Spectroscopy (DOAS), Global Ozone Monitoring Experiment 2 (GOME2), and Scanning Imaging Absorption Spectrophotometer for Atmospheric Cartography (SCIAMACHY) satellite observations. To assess the quality of the selected data products, comparisons with reference to the Brewer spectrophotometer single observations were made. The performance of the satellite observational techniques was assessed against the solar zenith angle and effective temperature, as well as against the actual shape of the vertical ozone profiles, which represent an important input parameter for the satellite ozone retrievals. The ground-based Dobson observations showed the best agreement with the Brewer data set (R-2 = 1.00, RMSE = 1.5%); however, significant solar zenith angle (SZA) dependency was found. The satellite overpass data confirmed good agreement with the Brewer observations but were, however, overestimated in all cases except for the OMI(TOMS), when the mean bias differed from -0.7 DU in the case of the OMI(TOMS) to 6.4 DU for the SCIAMACHY. The differences in satellite observational techniques were further evaluated using statistical analyses adapted for depleted and non-depleted conditions over the ozone hole period.