Traffic NO2 Overlay
What is the Traffic NO2 overlay?
The Traffic NO2 overlay is an Overlay which displays the impact of traffic air polution (in μg/m³ nitrogen dioxide) in different colors for the project area. These colors indicate traffic air polution of a location based on traffic flow and distance.
Traffic NO2 air polution overlay colors
File:Traffic NO2-Overlay Legend.jpg
Traffic NO2 overlay colors
Calculations
The calculations follow the standard rekenmethode 1 (SRM 1), as described on [1]:
Cjm = Ca,jm + Cb,jm
where:
- Cjm = annual average concentration [μg/m3]
- Ca,jm = annual average background-concentration (default = 0 [μg/m3], can be adjusted via the overlay attributes)
- Cb,jm = annual average traffic contribution to NO2 concentration [μg/m3]
Cb,jm= fNO2 * Cb,jm[NOx] + (B*Ca,jm[O3]*Cb,jm[NOx]*(1-fNO2))/(Cb,jm[NOx]*(1-Fno2)+K)
where:
- Cb,jm[NOX] = annual average traffic contribution to NOx concentration [μg/m3]
- Cb,jm[O3] = annual average concentration ozon [μg/m3]
- fNO2 = weighted fraction direct emitted NO2 [-]
- B = parameter (default 0.6)
- K = parameter for conversion NO to NO2 (default = 100 μg/m3)
References
The overlay calculations are based on Standard Calculation Method 1 (SRM1) as defined by the dutch government: wetten.overheid.nl