Figure 2.

Ambient air pollution modeling. Spatial variation in the three air pollution levels considered by the Danish DEHM-UBM-AirGIS system (left). The direct street contributions (red on the left) from traffic hotspots were estimated at the exact address level with the OSPM (right). The urban background concentration (green on the left) is calculated by the UBM and the regional background by the DEHM (blue on the left). AirGIS = A geographical information systems-based air pollution and human exposure modeling system; DEHM = Danish Eulerian Hemispheric Model; OSPM = Operational Street Pollution Model; UBM = urban background model.