NO2 in Munich 2016: high traffic => high NO2
This plot shows NO2 levels over the day in Munich in June and December 2016.
München-Landshuter-Allee on the left has about the highest NO2 levels
in all Germany,
and a lot of traffic — 120,000 to 150,000 cars and light trucks per day.
Surprise: high traffic => high NO2.