Body text
Why intensive VOC campaigns in Europe?
Many premature deaths in Europe are still attributable to exposure to major air pollutants like ozone, NO2 and particulate matter, despite reductions in emissions of their precursors over the last decades. High exposure is particularly important during heat waves, which are expected to become more frequent and intense in the future.
VOCs are major precursors of ozone and particulate matter (secondary organic aerosol or SOA). Because of their diversity in chemical identity and reactivity, and consequently in ozone and SOA formation potential, it is important to characterize the chemical VOC speciation and its spatiotemporal variation.
Such detailed information on VOCs and other pollutants, especially during extreme events, is needed to increase the accuracy of air quality forecasts in Europe.
Measurement campaigns and BIRA-IASB contributions
To address the lack of data, two Intensive Measurement Period campaigns have been organized as a collaboration between different European Research Infrastructures (EMEP, ACTRIS, RI-URBANS).
2022
The first campaign, taking place at 45 locations all over Europe from rural to industrial/urban, was held on 12-19 June 2022 and focused on air pollution during the 2022 European summer heatwave. At those locations air samples were taken for offline VOC analysis by three reference laboratories, providing concentrations of about 120 individual VOC species.
The offline measurements were complemented by online PTR-MS measurements at a number of sites, amongst which the ICOS/EMEP/ACTRIS mixed forest site at Vielsalm in the Belgian Ardennes, where BIRA-IASB deployed a PTR-ToF-MS VOC analyzer measuring VOCs in air sampled at the top of a 51 m high flux tower at one minute resolution (Fig. 1 top).
2024
The second campaign (named EUROVOC), with about 50 measurements locations, took place in September 2024. Because of the varying lifetime and evaporation potential of VOCs, this campaign focused on higher temporal resolution measurements over extensive spatial coverage, and over a full month period.
BIRA-IASB contributed to this campaign at two sites:
- the semi-urban Space Pole site at Uccle (Brussels) and
- the mixed forest Vielsalm site.
At Uccle, VOC measurements were performed with a PTR-Quad-MS analyzer, located in the MARTISLAB.be mobile ACTRIS national facility under development (Fig. 1 bottom). Data analysis is ongoing, but nice similarities and differences between the two Belgian sites could already be observed (Fig. 2).
