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Comment by a_square_peg | Hacker News Reader

I really hope people don't take this result at its face value - the model used and the approach is extremely simplistic, which is essentially a pseudo 2-D simplification of urban canyon geometry, a street with buildings on either sides. I worked with the referenced model as part of my master's thesis.

The bulk of urban heat island effect is driven by the radiative absorption of non-porous materials of the built-environment. Other heat waste put into the area accounts for less than something like 5% of the additional heat added when compared to rural areas.

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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.

[1] https://uk-air.defra.gov.uk/research/ozone-uv/moreinfo?view=...

[2] https://en.wikipedia.org/wiki/Light#/media/File:EM_spectrum....

[3] https://www.gov.uk/government/statistics/air-quality-statist....

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.

[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9678727/

> the model used and the approach is extremely simplistic

Seems like a constant in doomsday "science": making a model that bear ressemblance to reality as much as SimCity does, run it to get the expected conclusion, then extrapolate and conclude with newsworthy title that X or Y is true in reality.

>then extrapolate and conclude with newsworthy title that X or Y is true in reality.

It's worth noting that this portion is generally done by science reporters rather than the scientists. It's quite often the case that alarmist articles refer to research with much more measured and less sweeping claims.

extremely relevant

https://phdcomics.com/comics/archive.php?comicid=1174

Simplification and abstraction are, in fact, basic tenets of all scientific and philosophical disciplines.

https://plato.stanford.edu/entries/simplicity/

https://iep.utm.edu/simplici/

Of course, you are more than welcome to voice concrete concerns about this specific study, if you have any (beyond what the GP already said).

No they aren’t in this sense. I’m really not sure what you are attempting to convey here, maybe you’re being defensive for reasons unrelated to this topic, but your links aren’t talking about doing ultrasimplistic studies that don’t properly model the problem and treating results as fact. They mean simplicity in the Occams Razor meaning. Occams Razor is about the simplest solution being the most likely (e.g. don’t invent a ton of conclusions) and in fact is a philosophical argument for the existence of god.

Please don’t condescend people and definitely don’t go around arguing that science holds unrealistic simplicity as a core tenant.

I should have been more clear.

The comment I replied to seemed to make the following reasoning: "a lot of junk science uses oversimplified models; this work also uses an oversimplified model; therefore, this work is also junk science".

And my intention was to point out that this kind of reasoning is invalid, because simplification is an important aspect of the scientific process.

There's simplification, and there's "Spherical cow on a frictionless plane in a vacuum".

Yup, the only word a physics professor likes more than “negligible” is “trivial”.

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