Ground-level ozone is an air pollutant that, despite reductions in precursor emission in Europe, still represents a risk to vegetation and human health. This study is based on observations of ozone concentrations ([O-3]) from 25 European monitoring stations, north of the Alps within the EMEP network, during the 26-year period from 1990-2015. We analyzed the maximum and minimum hourly [O-3] as well as the seasonal cycle in relation to latitude. In addition, temporal trends were studied. The maximum [O-3] increased towards the south of the study area, while the yearly minimum of daytime mean increased towards the north. There was a strong correlation between the day of year when the maximum [O-3] occurred and latitude: the maximum [O-3] occurred earlier in the north. The maximum daytime [O-3] decreased at all stations while the minimum daytime [O-3] increased at most stations during the studied time period.

A unique long-term (1983-2013) dataset of sulfur and nitrogen deposition has been compiled for Sweden as well as the Baltic Sea and surrounding countries, based on quality controlled measurements and modelled fields, fused though advanced methods capturing spatial and temporal variations. The data set can be used for describing trends in deposition to various relevant surface types.Our reanalysis compares well to observations, but we have identified differences in dry deposition to coniferous forest. This calls for more in-depth studies of the dry deposition and improvements to the respective methods.We recommend more advanced methods of describing spatial variation than averaging or spatial interpolation of observed deposition.We estimate a significant decrease from the 1980s until today for both sulfur and nitrogen deposition (by ca. 80% and 30% respectively).Critical loads for coniferous and deciduous forests, mountain vegetation and wetlands have been surpassed mainly in the southwest Sweden, but also in southeast Sweden and the southern parts of Scandes Mountains. The situation is improving, but exceedances do still occur also in larger regions.

Ett unikt långt dataset (1983-2013) för svavel- och kvävedeposition har skapats för Sverige samt Östersjön och omgivande länder. Det baseras på kvalitetsgranskade mätningar och modellfält, kombinerade genom avancerade metoder för att fånga spatiala och temporala variationer. Datasetet kan användas för att beskriva trender i deposition till olika relevanta marktyper.Återanalysen stämmer väl överens med mätningar, men vi har identifierat skillnader i torrdeposition till barrskog. Detta visar på behov av djupare studier och metodikförbättringar för bestämning av torrdeposition.Vi rekommenderar mer avancerade metoder för att beskriva spatial variation än genom medelvärdesbildning eller spatial interpolering av uppmätt deposition.Vi finner en markant minskning från 1980-talet fram till idag för både svavel- och kvävedeposition (med cirka 80 % respektive 30 %).Kritiska belastningar till både barr- och lövskog, fjällmarker och våtmarker har överskridits framförallt i sydvästra Sverige, men också i sydöstra Sverige och södra fjällen. Situationen förbättras men överskridanden sker fortfarande även över större områden.