The use of radon as a tracer for air quality assessment: a case study in Bratislava, Slovakia

Air quality in urban areas is mainly controlled by emission sources and dispersion conditions. The mixing layer height (MLH) within which the pollutants are dispersed plays an important role in air pollution assessment. In this study, the MLH was determined based on the daily radon flux obtained from the European radon flux map and outdoor radon concentration measured in Bratislava, Slovakia. The radon-based MLH was compared with the boundary layer height obtained from the ERA-5 reanalysis dataset, showing good agreement. Using the Sturges grouping method and regression analysis, radon-based MLH showed significant correlations with the concentration of various atmospheric pollutants.