History annual mean ozone
The maps are based on the RIO-corine interpolation technique. The calculated concentrations are representative of areas with a surface area of 4x4 km2. The concentrations may locally be higher or lower. The modelled concentrations are subject to a certain degree of uncertainty. The uncertainty gains with the distance to the measuring station.
The annual mean ozone concentration is a measure of the background concentration in Belgium. It is clear that the ozone values will, in general, be higher in rural Wallonia than in Flanders and urban Brussels. The reason for this is that more ozone is broken down by NO because of the higher NOx emissions. By contrast, further downwind of the NOx emissions less ozone is broken down.