I've got F'all qualifications, but I can read and remember which means I also know Ozone (O3) levels can trap heat[1], and heat is Infra-Red (IR), a large part of the electromagnetic light spectrum [2] and ozone happens to be considerably higher in built up in areas[3], also contributing to the Heat Island Effect seen in towns and cities.
So whilst I cant find a copy of the study, and I recognise your comment on the modelling and approach being simplistic, the above also demonstrates that other factors like increased number of vehicles on the road, can be a factor as they contribute to ground level ozone and many also come with an air conditioning unit built into the car as standard today.
On a hot sunny day, the blacktop beneath the traffic jam is radiating more heat than all the cars on top of it are creating.
And a car engine is producing far more direct heat than the increase in ground-level ozone from exhaust pollution is increasing heat (from that same car).
Also the fact that cars have air conditioners is a total non-sequitur. The air conditioner in the car requires negligible energy compared to the force required to move 4000 pounds and 1-5 people at 70mph.
This maybe true, but I'd argue the air con still takes about 5mpg off the range of the fuel, but their existence and heat isnt magically disappearing, it spreads out helping to raise temperatures.
This link [1] suggests traffic jams can increase temperatures by 7 degrees Celcius.
And a car engine is producing far more direct heat than the increase in ground-level ozone from exhaust pollution is increasing heat (from that same car).
Also the fact that cars have air conditioners is a total non-sequitur. The air conditioner in the car requires negligible energy compared to the force required to move 4000 pounds and 1-5 people at 70mph.