HARMONIE

A European initiative HARMONIE to advance digital twin technology that helps cities reduce pollution and protect public health

Press release from the Barcelona Supercomputing Center - Centro Nacional de Supercomputación

• The European project HARMONIE is coordinated by the Barcelona Supercomputing Center and brings together a consortium of 19 entities from eight countries.
• The initiative will develop advanced digital twin tools — including a Citizen-Centric Digital Twin and a Lung Digital Twin — to help reduce air and noise pollution and assess their impact on citizens’ health.
• Five pilot cities across Europe — Barcelona, Lausanne, Sarajevo, Gävle, and Barakaldo — will serve as testbeds for innovation and evidence-based policymaking.

Urban air and noise pollution are silent threats affecting millions of Europeans every day. To help cities address this challenge, the HARMONIE project (Health Assessment Refinement for Mitigating Noise and Air Quality Effects) brings together European experts in environmental science, public health and digital technologies to develop advanced tools that support cleaner, healthier and more equitable urban environments.The initiative is coordinated by the Barcelona Supercomputing Center – Centro Nacional de Supercomputación (BSC-CNS).

Funded under the Horizon Europe call “Zero-Pollution Cities,” which contributes to the EU Mission “Climate-Neutral and Smart Cities by 2030,” the project takes a holistic approach to support informed policymaking. It improves air pollution and noise monitoring and modelling, while also providing tools to evaluate the health impacts of urban actions in both the short and long term.

To achieve these goals, HARMONIE works across two interconnected environments: real-world pilot studies and advanced digital twin simulations. In its five pilot cities — Barcelona, Lausanne, Sarajevo, Gävle and Barakaldo — the project collects detailed data on air and noise pollution, including emerging indicators such as oxidative potential (OP), as well as citizen mobility patterns, exposure levels and health indicators, with a particular focus on vulnerable populations.

These real-world insights feed into two complementary digital twin systems. The first, the Lung Digital Twin (LDT), adds a unique physiological dimension by modelling how pollutants interact with the human respiratory system. Based on patient specific geometries and with the data provided by high resolution model of inhaled pollutants, it simulates airflow and the transport and deposition of inhaled particles inside the airways, enabling detailed assessments of inhaled dose, susceptibility and health impact pathways towards oxidative stress.

In parallel, the Citizen-Centric Digital Twin (CCDT) provides the urban-scale perspective by integrating detailed pollution mapping with mobility patterns, social dynamics and exposure modelling. It shows not only where people are exposed to pollution, but also the attributable health impacts. The CCDT also enables “What-If” simulations that allow policymakers to test potential urban measures in a safe, data-driven environment — helping them evaluate alternatives and design interventions that are both effective and equitable in terms of health benefits.

The HARMONIE consortium includes 19 partner institutions: the Barcelona Supercomputing Center, Universidad de Deusto, Bettair Cities SL, Agencia Estatal Consejo Superior de Investigaciones Científicas (CSIC), Fondazione Bruno Kessler (FBK), University of Bristol, Factual Consulting SL, Max Planck Institute for Chemistry (MPIC), Pompeu Fabra University (UPF), Swiss Tropical and Public Health Institute (Swiss TPH), Unisanté – University of Lausanne, Air Quality Consultants (AQC), the City of Sarajevo, University of Gävle, the Diputació de Barcelona, the Barakaldo Municipality, University of Nova Gorica, University of Basel, and the Lausanne Municipality.

“Health should be a priority in any urban planning and not be left exclusively to the medical profession", said Beatriz Eguzkitza, project coordinator and researcher at the Barcelona Supercomputing Center (BSC). “Many air pollutants that harm people’s health also play a role in climate warming. Putting health at the centre of urban decisions drives measures that reduce pollution, enhance well-being and contribute to more resilient, equitable and sustainable cities.”

The group around Dr. Thomas Berkemeier at MPIC leads the project area that uses computational modelling to link the underlying principles of air pollution's health effects—drawing from chemistry, physics, and biology—with their broader implications for public health in European cities. "We will utilize the detailed air pollution maps developed within the consortium to assess how inhaling air in various locations across the city affects lung chemistry. These findings will enable our partners to develop targeted strategies (or leave recommendations?) aimed at mitigating the health impacts of air pollution in urban areas.", Thomas Berkemeier explains.

HARMONIE’s holistic approach not only advances environmental monitoring and modeling but also puts citizen engagement and behavioral insights at the heart of zero-pollution strategies. The initiative provides open-source, scalable digital solutions for all cities and populations, supporting the EU’s broader ambitions for climate neutrality, health equity, and zero pollution in at least 100 European cities, with the potential to expand globally.

EU funding acknowledgment

The HARMONIE project has received funding from the European Union's Horizon Europe programme under grant agreement No 101238943.

Funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Climate, Infrastructure and Environment Executive Agency (CINEA). Neither the European Union nor the granting authority can be held responsible for them.