Satellite Navigation systems like TomTom, Google Maps and OpenStreetMap-based services are pervasively used in our cities to facilitate and speed up reaching the desired destination. They are typically optimized to minimize an individual driver's travel time without considering their impact on traffic, whether a street can absorb the traffic, or if some routes compromise drivers' safety.

When dealing with socio-technical systems, the aggregation of selfish optimal individual suggestions may negatively impact the collective level, worsening the wellness of society as a whole and leading to discomfort, particularly when individuals share a resource with a limited capacity, as in the case of road networks.

For instance, if the navigation system recommends all vehicles to travel on the same road to reach a destination, congestion may emerge on that road.

The adverse traffic effects unintentionally exacerbated by navigation systems can impact the environment. Indeed, vehicular traffic represents a critical hazard to urban sustainability, contributing to one of the most severe problems affecting conurbations, air pollution, which negatively impacts human health and the environment.

This study aims to assess and quantify the impact of navigation systems on traffic and the urban environment through realistic simulations and what-if analysis. In particular, we consider CO2 emissions to measure the effect of traffic on the environment. Furthermore, we will assess how much the percentage of vehicles that follow different types of indications impacts on the CO2 emissions and their concentration on the roads of the network.