But the air above some streets is quite polluted in terms of NOx and particulate matter, and the air above the open road is very clean. In the cities, the stree

But the air above some streets is quite polluted in terms of NOx and particulate matter, and the air above the open road is very clean. In the cities, the street pollution levels vary a lot based on time (peak, off-peak) and day (weekday, weekend, holiday, public event day). I wonder if there would be any useful signal left in the noise.