Impact of the 2021 La Palma volcanic eruption on air quality: Insights from a multidisciplinary approach.

The La Palma 2021 volcanic eruption was the first subaerial eruption in a 50-year period in the Canary Islands (Spain), emitting ~1.8 Tg of sulphur dioxide (SO) into the troposphere over nearly 3 months (19 September-13 December 2021), exceeding the total anthropogenic SO emitted from the 27 European Union countries in 2019. We conducted a comprehensive evaluation of the impact of the 2021 volcanic eruption on air quality (SO, PM and PM concentrations) utilising a multidisciplinary approach, combining ground and satellite-based measurements with height-resolved aerosol and meteorological information.