Connecting urban data, pollution exposure, and health effects

Our digital twins

Two scales for greater impact

Our Digital Twins at the service of urban health

At HARMONIE, we develop two complementary digital twins — the Citizen-Centric Digital Twin (CCDT) and the Lung Digital Twin (LDT) — that operate at different scales. Together, they provide a full picture of how pollution affects people and how cities can design more effective policies.

Pilot data from the five cities feeds the digital twins, ensuring that simulations and insights reflect real conditions, real behaviours and real health risks.

Citizen-Centric Digital Twin (CCDT)

The CCDT reveals how pollution, mobility and behaviour interact across the city. This gives policymakers a powerful decision support tool to design smarter but healthier urban strategies.

What CCDT provides:

  • It brings together pollution maps, mobility patterns and social dynamics that reveal how people actually move, live and become exposed to pollution in the city.
  • It shows not just where pollution is, but who it affects — and the health impacts linked to that exposure.
  • Let cities explore “What-If” scenarios to see how different urban interventions could change pollution and health outcomes.
  • It helps policymakers compare options and design effective urban interventions.

Lung Digital Twin:

The Lung Digital Twin introduces a unique physiological dimension to HARMONIE. It models how pollutants interact with the human respiratory system using patient-specific airway geometries and high-resolution pollutant input from the project.

What the LDT provides:

  • Simulation of airflow and particle deposition throughout the airways.
  • Estimation of inhaled dose.
  • Assessment of vulnerability and susceptibility in different population groups.
  • Modelling of oxidative stress pathways and early biological damage.
  • A mechanistic link between environmental exposure and individual health effects.

Why it Matters

A full picture of pollution and health

Together, the two digital twins connect urban exposure with its real health impacts.

Better, fairer decisions

Cities can test measures in advance and choose those that most effectively reduce pollution and protect public health.

Citizen-focused

Involves communities in evaluating and shaping strategies.

Built to last

A scalable digital framework that cities can maintain and expand beyond the project.