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Surprise surprise, vegetation is way better than concrete when it comes to being comfortable in a city
Genuine question for people in the field. My understanding is that the cooling effect of trees is primarily driven by evaporative cooling. That is, the shade effect only really exists because the plant does not shrivel up and die due to storing water. How much more effective are trees vs. big swamp coolers? Even in this article, they admit that daytime cooling of half a degree requires 3 times more water.
Trees excel at harvesting water. When you water a tree, there is evaporative cooling like an artificial cooler but during the night, the dew falls back on the leaves and the ground where some of it finds its way back to the trees (possibly via an invertebrate first). Also the reflectiveness of leaves helps. Then there's the soil where layers of dead leaves, wood and others accumulate, sequester CO2 and create a sponge. Finally, by virtue of making the region cooler, rain is more likely to fall. Humans can probably engineer something better but the bar is high.
Some of it is converted to chemical energy used for the tree’s growth etc chatgpt says 30-40%
That captcha sure reduces the effectiveness of me reading that by 100%.
I've just been presented with a captcha thingie asking me to select all things that can be picked up by a pair of chopsticks described as "the tool in the image"

Fuck off.

Then that vanished and another even more vapid effort appeared.

Fuck off.

If you need to piss around with this sort of nonsense, you probably shouldn't be entrusted with a website.

Is it just me, or has anyone also noticed that trees in southern climates closer to the equator (not jungles) have very few leaves and shade as opposed to trees in climates away from the equator (not tundras)?

What happens if you import northern US trees, the ones that produce a lot of shade, into southern states? Has this been tried?

It is also why there is very little shade in, say, Florida. Only occasional parts of the Martin Grade “scenic” highway look like a regular scene in the north.

any group strategy to push back against the overuse of whole-page captchas ?

Do we all need to run an AI browser plugin now that auto-fills cloudflare captchas ?

I saw video last week in India there was similar experiment done in sun the temperature 45 degrees C and 30 step walk under the tree the temperature 36 degrees C. We need more trees as an easy solution
I hope there would be enforced regulation around this kind of thing in cities in India. In residential areas, it's common that your house takes up almost all of your available plot space, and on top of that mostly constructed from concrete.

Air temperature is already high (e.g. 36C at my location just now), and radiant heat from sun and concrete can make the felt temperature more like 60C.

It's sad that new real-estate layouts continue to be approved, which will only be good for this type of dense concrete hell.

I don’t think planting trees is only for cooling things down. Sometimes it’s just about helping people feel like they can go outside. In really hot places, even a bit of shade can change your mind about stepping out.
The best way to produce shade in the Nevada desert is with solar panels.

The sky is rarely cloudy and solar just blasts all day every day here.

I covered my backyard in Vegas with ground panels and now I charge my EV off of a 100% off grid solar system. The sun provides enough energy in my small yard for 2-3x my driving needs.

Solar panels can be engineered to also optimize cooling, by selectively increasing their reflectivity at wavelengths that are neither useful for electricity production nor for radiation of their waste thermal energy.

https://web.stanford.edu/group/fan/publication/Li_ACSPhotoni...

"[...] we design a photonic cooler made of one- dimensional photonic films that can strongly radiate heat through its thermal emission while also significantly reflecting the solar spectrum in the sub-band-gap and ultraviolet regimes. We show that applying this photonic cooler to a solar panel can lower the cell temperature by over 5.7 °C."

As a matter of local trivia, today (2025.07.01) we had a wind storm in vegas that downed many trees. :)
There is a place in So Cal now called The Aspens South Coast we lived in 30 years ago. It has (had?) an incredibly dense concentration of trees, something I’ve not seen since in that region, which is of course desert.

This time of year when you opened the gate that separated the treed interior from the parking lot you felt like the air conditioning had been turned on. We have very fond memories of the place. Its only disadvantage for me was that spring caused my allergies to go crazy.

Totally worth it.

I was in a heat wave in Andalusia region in Spain and was visiting Medieval Arabic monuments and gardens. They have very interesting designs in terms of shapes, plant and tree selections and wall placements that produced very noticeable temperature differences. To say nothing of the scent of the lemon trees.
This is a repeating study, seeing this again and again, so not sure about its novelty.

In Europe we even assigned our first "Chief Heat Officer", which makes total sense.

I recently bought some wooded land and unlike most people I know I've been extremely selective cutting down trees on it.

It's actually comfortable to be outside there. Even in the summer it's almost completely shaded. I was kind of surprised how extreme it is. I know trees make it harder to work and if you're hiring people they probably can't tolerate it but since I'm doing everything myself I don't have to clear everything and wait for it to grow back.

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This needing a study is like the discovery in Idiocracy that soil needs to be watered with water, not Brawndo's soft drink.

Plant trees, not ACs...

North America's greed for energy resources is just bonkers from an outside perspecive.

Why is Las Vegas, NV referred to as ‘Vegas’, but Los Angeles, CA is not referred to as ‘Angeles’?
I've only scanned the abstract but the conclusion seems too weak given the other stated findings. Sure given different metrics (air temp vs radiant heat) may give different stories for different trees, but that wouldn't lead me to conclude it needs to be evaluated on a "case by case basis" more so than the metric depends. That is not the same thing as "case by case basis."

They should be more proud of their findings. Why insult it out of the gate?

I think that's why Alabama despite all its flaws doesn't have quite as much projected warming as other southern states: lots of trees.
> The selected tree species is Bur Oak, given that it is included in the SNWA Regional Plant (SNWA 2021) list, it is marked as a street tree in the list...

Who the hell is planting oaks in Vegas? Oaks are non native and moderately water intensive trees. If this study is based on oaks, it calls into question the validity of the data since this is a tree that absolutely does not belong in the Mojave desert.