A team from the ITACA Institute at the Universitat Politècnica de València (UPV), in collaboration with the Institute of Corpuscular Physics (IFIC)—a joint centre of the CSIC and the University of Valencia (UV)—has developed a methodology that allows for the calculation of pollutant gas emissions produced by traffic in each street of the city of València, hour by hour. The system combines data collected from traffic sensors already installed in the city with standardised and internationally recognised emission models.

Thanks to this work, it has been possible to identify the areas most affected by traffic-related pollution. The most polluted areas are the northern (Avinguda de Catalunya, Avinguda dels Germans Machado) and western (Avinguda del Cid, entrance via Tres Forques) access points to the city. Other roads with high traffic density, such as Avinguda de Pérez Galdós and Avinguda de Giorgeta, also stand out for their high levels of emissions.

According to the study, in 2021, road traffic in València generated more than 600,000 tonnes of greenhouse gases, as well as pollutants such as nitrogen oxides, carbon monoxide, volatile organic compounds, and particulate matter.

The Impact of Cycle Lanes

The method developed by the team from the ITACA Institute at UPV and the IFIC (CSIC-UV) allows the evaluation of the impact of new sustainable urban mobility measures. As an example, the ITACA team analysed the effect of transforming a traffic lane into a cycle lane on Avinguda del Regne de València. After the intervention, emissions in that section were reduced by over 45% during rush hours.

“The model allows for the direct estimation of the impact of specific measures, with a level of detail that was previously unattainable. This makes it possible to simulate which measures would have the greatest impact on emission reduction and thus allocate resources as efficiently as possible,” says Edgar Lorenzo Sáez, researcher at the ITACA Institute.

Emissions Reduction Between 2016 and 201

Furthermore, the study by the UPV and IFIC team shows a progressive reduction in emissions in València between 2016 and 2021. During this period, pollutants such as carbon monoxide and volatile organic compounds decreased by more than 30%. According to the study, this decline is linked to a reduced presence of diesel vehicles and an increase—still limited but growing—in hybrid and electric vehicles.

A More Precise System

Until now, air quality monitoring in València has relied on data from nine fixed stations distributed throughout the city.

“These stations do not provide a complete view of the city. Our system allows for full coverage, even in streets and neighbourhoods where there are no direct monitoring stations,” says Jose Vicente Oliver, professor at UPV and researcher at the ITACA Institute.

“This detailed analysis capability is especially useful for planning low-emission zones, prioritising interventions in sensitive areas (such as around schools or healthcare centres), and determining whether certain measures shift pollution to other areas or times. This ensures that a measure does not merely relocate emissions from one part of the city to another, causing environmental injustice,” adds Javier Urchueguía, professor at UPV and researcher at the ITACA Institute.

The IFIC contributed to processing the data collected by over 3,500 electromagnetic loops distributed across the city, which measure the passage of cars, bicycles, and scooters.

“Modern data analysis techniques have been key to cleaning, validating, and structuring the vast amount of information generated by the traffic management system,” explains Miguel García Folgado, CSIC researcher at the Institute of Corpuscular Physics. “Thanks to this, it has been possible to study the impact of traffic on urban pollution with unprecedented spatial and temporal resolution, allowing us to precisely identify emission hotspots.”

To carry out this study, the UPV and IFIC team collaborated with València City Council, which provided access to the traffic management system data, and received funding from the Agència Valenciana de la Innovació (AVI) as part of the AVI AirLuisa project.

References:
Edgar Lorenzo-Sáez, Javier F. Urchueguía, Miguel García Folgado, Jose-Vicente Oliver-Villanueva, Methodology development for high-resolution monitoring of emissions in urban road traffic systems, Atmospheric Pollution Research, Volume 16, Issue 9, 2025, DOI: https://doi.org/10.1016/j.apr.2025.102600