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Countering climate change with cool pavements

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Re: Countering climate change with cool pavements

#11

Post by ClumsyPilot »

godelski wrote: post #9
frosted-flakes wrote: post #7

Earlier quoted context omitted.

Why would they cost a fortune to maintain? Apart from leaf collection and end-of-life removal, what costs are associated with street trees?

They require water, which requires irrigation (may not already be in place and of course has logistical problems), trees also root systems can lift and crack sidewalks/pipes/other things, you now have biological contaminants, there's bugs and fungus and things that can spread, and so much more. I'm not saying we shouldn't do this. I really like seeing plant life in cities and I think it really makes a psychological d…

"now have biological contaminants, there's bugs and fungus"

Dude, we have rats running around, pigeons nesting and pooping, what biological contaminants?

Re: Countering climate change with cool pavements

#12

Post by godelski »

ClumsyPilot wrote: post #11
godelski wrote: post #9

Earlier quoted context omitted.

They require water, which requires irrigation (may not already be in place and of course has logistical problems), trees also root systems can lift and crack sidewalks/pipes/other things, you now have biological contaminants, there's bugs and fungus and things that can spread, and so much more. I'm not saying we shouldn't do this. I really like seeing plant life in cities and I think it really makes a psychological d…

"now have biological contaminants, there's bugs and fungus" Dude, we have rats running around, pigeons nesting and pooping, what biological contaminants?

Just because biological contaminants exist doesn't mean adding more creates more issues. More trees also means more rats and pigeons. What's your argument? That just because we already have a bad thing doesn't mean that a similar bad thing isn't bad? That doesn't make much sense and is a pretty lazy argument.

Re: Countering climate change with cool pavements

#13

Post by harmmonica »

clairity wrote: post #3

> “Conversely, by reflecting light — called incident radiation — onto nearby buildings, cool pavements can warm structures up, which can increase AC usage in the summer and lower heating demand in the winter.” this is one of the reasons why i'm an advocate for street trees, and urban foliage in general (cuts down both incident and reflective radiation), and why i'm maddened when i see urban trees cut down or cut back…

from one LA resident to another, amen to that. we were just walking down our street this morning and discussing, for the umpteenth time, whether our neighbors would actually be willing to take care of trees if we went out and bought them and planted them. the problem, as other commenters have pointed out, is that they do require upkeep, but since they're living/breathing things the more hardy ones can really be abused and still survive. The question is how do you incentivize the people who benefit from the trees--the residents, businesses, other local stakeholders--to actually maintain them?

on our street there are countless trees that were likely planted decades ago, but a lack of care by the residents makes them mere shadows of their potential.

and for anyone interested, LA's a great example of how trees provide a return on investment (actual dollar return outside the tremendous ecological benefits). go onto google maps and look at the satellite view. people who have never been here can point out the expensive neighborhoods because they are the greener ones.

Re: Countering climate change with cool pavements

#15

Post by aaaaaaaaaaab »

_ofdw wrote: post #6

This totally nerd-sniped[0] me, and now I'm going down the rabbit hole wondering if there's a business opportunity for generating electricity via the thermoelectric effect[1] and thus literally cooling the pavement by pulling some energy out and putting it to good use. [0] https://xkcd.com/356/ [1] https://en.m.wikipedia.org/wiki/Thermoelectric_generator

I’ll save you some time: absolutely not.

Re: Countering climate change with cool pavements

#16

Post by puffyvolvo »

clairity wrote: post #3

> “Conversely, by reflecting light — called incident radiation — onto nearby buildings, cool pavements can warm structures up, which can increase AC usage in the summer and lower heating demand in the winter.” this is one of the reasons why i'm an advocate for street trees, and urban foliage in general (cuts down both incident and reflective radiation), and why i'm maddened when i see urban trees cut down or cut back…

While I initially would prefer the idea of more street trees the nagging voice in the back of my head continues to worry about unintended consequences.

A big one regarding more trees is more maintenance, you've already pointed out how terrible maintenance can be, and lawns alone are an incredible example of just how inefficient we handle plants in the name of some arbitrary aesthetic, tons of water wasted, many hours spent trimming things to some ideal size that turns out to be terrible for the plant itself, etc.

Of course my paranoia doesn't ignore cool pavements either; the reflectivity does bring some mild worries: some skyscrapers are known to cause large amounts of concentrated reflective heat, but those are due to the more mirror-like reflective properties of glass rather than the diffusive matte grey/whites of these pavements. I also worry about visibility, could we end up having a "snow blindness" effect? Would driving be affected as the harsh unnatural dark contrast of a typical road is very easy to spot compared to...everything else. I'm ofcourse aware not all roads are this black but you can't deny bright yellows and whites of road markers on a deep black road would be easier to pick up on than on a greyish road.

Re: Countering climate change with cool pavements

#18

Post by MichaelGroves »

frosted-flakes wrote: post #7
pharmakom wrote: post #5

Earlier quoted context omitted.

I also like urban trees but remember they cost a fortune to maintain! For example, urban trees have to be expertly managed for disease along transit lines.

Why would they cost a fortune to maintain? Apart from leaf collection and end-of-life removal, what costs are associated with street trees?

Tree limbs die all the time. Normally when disease or damage kill a tree branch, it isn't a big deal because the tree is in a forest and probably won't fall on anybody or damage any property under it. In a city, you can't ignore a widowmaker. The risk of it damaging property or flat out killing somebody is too high, you have to pay to get it safely removed. Often this becomes "end-of-life removal" because it's deemed safer or cheaper in the long run to remove the tree entirely. So now you have a green mostly alive tree being chopped down because one of the limbs died, and everybody in the neighborhood thinks you're a tree butcher but nobody else wants to chip in to have it maintained.

Re: Countering climate change with cool pavements

#19

Post by llukas »

aaaaaaaaaaab wrote: post #15
_ofdw wrote: post #6

This totally nerd-sniped[0] me, and now I'm going down the rabbit hole wondering if there's a business opportunity for generating electricity via the thermoelectric effect[1] and thus literally cooling the pavement by pulling some energy out and putting it to good use. [0] https://xkcd.com/356/ [1] https://en.m.wikipedia.org/wiki/Thermoelectric_generator

I’ll save you some time: absolutely not.

https://www.ucdavis.edu/news/anti-solar-cells-photovoltaic-c...

Not pavement but still

Re: Countering climate change with cool pavements

#20

Post by NumberWangMan »

puffyvolvo wrote: post #16
clairity wrote: post #3

> “Conversely, by reflecting light — called incident radiation — onto nearby buildings, cool pavements can warm structures up, which can increase AC usage in the summer and lower heating demand in the winter.” this is one of the reasons why i'm an advocate for street trees, and urban foliage in general (cuts down both incident and reflective radiation), and why i'm maddened when i see urban trees cut down or cut back…

While I initially would prefer the idea of more street trees the nagging voice in the back of my head continues to worry about unintended consequences. A big one regarding more trees is more maintenance, you've already pointed out how terrible maintenance can be, and lawns alone are an incredible example of just how inefficient we handle plants in the name of some arbitrary aesthetic, tons of water wasted, many hours…

I agree with you on the matter of lawns, but not on street trees. Yes, they require maintenance, but they make a massive difference in the comfort of people walking, which is a big factor in people deciding to walk rather than drive, as well as increasing the general attractiveness of the area to potential residents who might otherwise live in a car dependent suburb of something. When you add up all the benefits, I'd consider street trees to be analogous to brushing your teeth-takes a bit of effort but the cost of not doing it is far greater.

This of course applies mostly to areas that are hot for a good portion of the year.

And I have the same concerns as you about the reflective pavement.

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