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Spectral ultraviolet (UV) radiation measurements have been performed with a Brewer spectroradiometer at Sodankylä (67°N) since 1990. The site is located in the Arctic and affected by stratospheric ozone depletion during spring. The UV time series includes years of strong ozone depletion, which led to increased UV levels since the beginning of the 1990s. In this work, we have analyzed the time series of the time period 1990–2021. Spectral changes are analyzed in steps of 1 nm for wavelengths between 300 and 325 nm. We performed sensitivity tests by varying the start and end year of the analysis and found that results are strongly dependent on the chosen time period. Due to the high year-to-year variability in monthly means, no significant trend was found. Typical maximum values, UV index 5, occur during summer time, because the Sun is still low in the sky during the Arctic ozone depletion period, leading to UV index values lower than in the summer. However, at Marambio (64°S), Antarctica, measurements with a GUV multichannel radiometer show that UV levels can exceed those of summer time also during the ozone depletion period. The Finnish Meteorological Institute (FMI) has started Marambio's UV measurements in 2017 in collaboration with Servicio Meteorológico Nacional, Argentina. Here we show results for the first four years of measurements 2017-2021. The maximum UV index measured during that time period, UV index 13, was measured in November-December in 2020 as a consequence of the strong and long-lasting polar vortex of that year. [ABSTRACT FROM AUTHOR]