Series: NILU OR 62/2011
NILU OR 62/2011 (pdf)
Summary: The Air Quality in Oslo in 2025 will be worse than previously expected. If the present trend of a high percentage of sold diesel passenger cars will continue it will make the NO2 levels from light vehicles higher in 2025 compared with 2010.This is due to higher emissions of diesel cars in real driving cycles compared to the emissions standards. The calculation of NO2 concentrations in 2025 shows levels that will violate the directives¿ limit values in a large area of Oslo. Calculations are done for 2010 and 2025 and results from totally 9 dispersion calculations are shown. Firstly 4 reference calculations are considered looking at the effect of the difference of real emissions factors taken from measurement under typically urban driving-cycle compared with the emission standards. There have also been done 3 mitigation calculations with incentives for lower diesel cars sales numbers and two short-time measures limiting the use of cars. None of these measures are sufficient for keeping the limit values in Oslo and Bærum in 2025 and hence more measures are needed.