The research, based on data collected between 2000 and 2019, indicates that all urban stations in the region show a growing trend of this pollutant. Atmospheric pollution remains a significant environmental and social challenge, especially in urban areas with high traffic density and intense industrial activity.
Average ozone concentrations in urban stations range between 38 and 56 micrograms per cubic meter (µg/m³). The lowest values have been recorded in areas with heavy traffic, such as the Pista de Silla station in Valencia, while areas like Gandia exceed 56 µg/m³. In contrast, rural stations located at higher altitudes show the highest levels, with averages exceeding 90 µg/m³, indicating that ozone accumulates far from the emission sources of its precursors.
“"The alert threshold has not been exceeded on any occasion at the measurement points in the Valencian Community. However, the upward trend is clear and consistent with studies conducted in other parts of the world."
Tropospheric ozone forms when nitrogen oxides and volatile organic compounds react under solar radiation. This pollutant is harmful to health and ecosystems at ground level, unlike ozone in the upper layers which protects against ultraviolet radiation. Levels are higher during the central hours of the day and in the afternoon, as well as during spring, influenced by factors such as temperature and air circulation.
The study also analyzes other pollutants such as nitrogen oxides and suspended particles, which are strongly influenced by traffic and industrial activity. A "weekend effect" has been observed, with higher ozone levels on Saturdays and Sundays in urban environments. According to the European Environment Agency, poor air quality contributes to nearly half a million premature deaths annually in Europe, highlighting the need to strengthen pollution monitoring and reduction policies. The study was conducted with data from the Valencian Air Pollution Monitoring and Control Network and was funded by the Generalitat Valenciana.
