NO2 is a problem in the largest towns
Target4.4 To ensure safe air quality. Current knowledge indicates that air is safe to breathe if concentrations of pollutants are below the following limits: – Annual mean concentration of PM10: 20 μg/m3 – Annual mean concentration of PM2.5: 8 μg/m3 – Annual mean concentration of NO2: 40 μg/m3
IndicatorTrends in annual mean concentration of NO2, focusing on places where levels exceed the levels considered to be safe
Are we moving in the right direction? Published by the Norwegian Environment Agency
The national air quality targets apply to the entire country, but pollution problems are greatest in towns. In Norway, particulate matter and nitrogen dioxide (NO2) are the most important components of local air pollution.
NO2 is a problem in several towns, but the national target is only exceeded in the largest towns in Norway.
Since 2014, the national target has only been exceeded in Oslo and Bergen. In the years around 2010 the levels were also exceeded in Trondheim, Stavanger and Drammen. It is too early to conclude whether the decline in NO2 in these towns will continue.
Increased traffic volumes and the transition from gasoline to diesel fuel in cars, are the main reasons why NO2 levels exceed the national target. Local meteorological variations also contribute to high NO2 levels in some years. For example, 2010 was an extreme year in Bergen. This was due to a combination of exhaust gases, particularly from diesel vehicles, and periods of cold, stagnant air.
Future NO2 levels
Unless extensive traffic regulation measures are introduced, the national target will be exceeded in the largest towns in the coming years. NO2 levels depend a lot on the size of the towns, and that is why particularly Oslo, the capital of Norway, will face challenges.
New requirements in EU regulations will reduce emissions from each vehicle, but the effect on the NO2 levels will take time and the reduction will be counteracted if the rise in traffic volume continues.