| Summary: | From January 2016 until August 2018, an automated Long-Path Differential Optical Absorption Spectroscopy (LP-DOAS) instrument was operated at the German research station Neumayer III (NMIII) in coastal Antarctica to measure trace gas mixing ratios in the boundary layer close to the ground (average altitude above the snow surface: 4m). Two different atmospheric light paths with total lengths of 3100 m and 5900m were used depending on visibility. The DOAS evaluation of I2 was performed between 532.5 and 549 nm. Fits with residual optical density RMS (root mean square) values larger than 4.0e-4 were discarded. The resulting mean residual RMS is 2.3e-4. The mean detection limit is 78 pmol/mol. The data sets include the observations below the respective detection limit scattered around 0, which due to the spectral analysis with the DOAS approach can include negative values. I2 was not detected above a 3-sigma detection limit. Since total errors and hence detection limits are determined from spectral information, the detection limit of I2 can serve as an upper limit for an atmospheric presence. The mixing ratios provided here were calculated using meteorological data from Neumayer III station already published on PANGAEA. A list of data sets is included in the "Related to" section of the bibliography this data set is part of. The spectral raw data of the measurements is stored on the measurement data server of the Institute of Environmental Physics, University of Heidelberg.
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