Axis 1 : Air pollution

Ljubljana, is widely perceived as a “green” and beautiful capital, and it has indeed invested in sustainable urban policies, such as pedestrianising its city centre, expanding green spaces, improving the Ljubljanica River corridor, and adopting a zero-waste strategy and circular-economy principles. At the same time, publicly available air-quality monitoring data show that the city still faces significant seasonal air-pollution challenges: in winter, Ljubljana frequently struggles with particulate pollution (PM10), linked to dust, traffic emissions, industry, and especially smoke from fires and domestic wood heating, while in summer ozone (O₃) levels rise. The above are aggravated by the city’s location in the Ljubljana basin, where air circulation can be low, allowing pollutants to accumulate. Alongside PM10 and ozone, other monitored pollutants include SO₂ (associated mainly with fossil-fuel burning and industrial activity) and NOx (largely produced by fuel combustion from mobile sources such as vehicles and stationary sources such as energy facilities). To make this situation visible and continuously present in public awareness, the partner MoTA has established Cyanometer, a tool that draws on measurements from the ARSO Ljubljana Bežigrad station and displays real-time air quality on a colour scale (red to green), highlighting the main pollutant when pollution peaks, serving as an ongoing reminder of the condition of the city’s most essential life-support system: the air we breathe.