Total column ozone measurements by the Dobson spectrophotometer at Belsk (Poland) for the period 1963–2019: homogenization and adjustment to the Brewer spectrophotometer

Abstract. The total column ozone (TCO3) measurements by the Dobson spectrophotometer (serial no. 84) have been carried out at Belsk station (51∘50′ N, 20∘47′ E), Poland, since 23 March 1963. In total, ∼115 000 intraday manual observations were made 31 December 2019. These performed for different combinations of double wavelength pairs in ultraviolet range and observation types, i.e., direct sun (DS), zenith blue (ZB), cloudy (ZC) depending on weather conditions. long-term stability instrument was supported frequent (almost every 4 years) intercomparisons with world standard spectrophotometer. Trend analyses, based monthly yearly averaged TCO3, can be without any additional corrections to values. To adjust these data Brewer observations, which also Belsk, a procedure is proposed account less accurate under low solar elevation, presence clouds, temperature dependence absorption. adjusted time series shows that Brewer–Dobson differences are about ±0.5 %. TCO3 database, divided into three periods (1963–1979, 1980–1999, 2000–2019), freely available https://doi.org/10.1594/PANGAEA.919378 (Rajewska-Więch et al., 2020).