Spatial variability of VOCs, ozone, and carbonaceous aerosols during the 2022 European summer heatwave

The data presented here originate from the EMEP/ACTRIS Intensive Measurement Period (IMP2022), which focused on one week of coordinated measurements of volatile organic compounds (VOCs), ozone, and organic aerosol tracers at selected European monitoring sites from 12–19 July 2022. The campaign was conducted during the European heatwave of July 2022, characterized by persistent high-pressure conditions, record-breaking temperatures, widespread ozone exceedances, and concurrent atmospheric new particle formation and growth events. A total of 31 sites participated in the campaign. Of these, 14 sites measured the main VOC species across all major compound categories, including non-methane hydrocarbons (NMHCs), isoprene, oxygenated VOCs (O-VOCs), aromatics, and monoterpenes, while 23 sites analysed organic tracers in particulate matter. In total, more than 120 VOC species and 47 particulate organic tracers and related compounds were measured during the campaign. For VOCs, organic tracers, and particulate matter (PM), data were aggregated to daytime averages between 12:00 and 16:00 UTC, corresponding to the sampling period of the manual measurements. Sampling durations varied between 1 and 4 hours within this time window. For ozone, the daily maximum 1-hour concentration was used instead of the daytime mean. The measurements were designed to improve understanding of the interactions between meteorology, anthropogenic and biogenic emissions, ozone formation, secondary organic aerosol (SOA) production, and nanoparticle growth during extreme pollution episodes. The dataset supports investigations of precursor contributions to ozone and SOA formation and provides observational constraints for atmospheric chemistry and transport model simulations.