More Cities Address ‘Shade Deserts’ as Extreme Heat Triggers Health Issues
More Cities Address ‘Shade Deserts’ as Extreme Heat Triggers Health Issues
Where trees are growing — and who has access to their shade — affects health and well-being, especially in one of the hottest states in the country.
Neighborhoods with more trees and green space stay cooler, while those coated with layers of asphalt swelter. Lower-income neighborhoods tend to be hottest, a city report found, and they have the least tree canopy.
The same is true in cities across the country, where poor and minority neighborhoods disproportionately suffer the consequences of rising temperatures. Research shows the temperatures in a single city, from Portland, Oregon, to Baltimore, can vary by up to 20 degrees. For a resident in a leafy suburb, a steamy summer day may feel uncomfortable. But for their friend a few neighborhoods over, it’s more than uncomfortable — it’s dangerous.
Trees are a good thing? Who knew?
49Here’s a study from 2019 quantifying the superiority of trees over artificial shade structures: https://www.sciencedirect.com/science/article/abs/pii/S1618866718304291
Tl;dr is that tree shade is 2-5° C cooler than artificial shade. Time to start lobbying city councils to plant trees all over and ideally include fruit trees for some urban edible forest action.
12Wouldn't it depend on the artificial structure and how much water you are adding?
Like a piece of foam painted with pure white IR-emissive CaCO2 is going to be >10 degrees cooler than a black panel with an air gap and glass.
There are likely tradeoffs (water and cost for the tree being the main downside).
Personally I think both is good https://www.pv-magazine.com/2023/08/25/sunagri-reveals-agrivoltaics-performance-in-heat-waves/
Less water, more elecricity and cooler temps than either alone.
3
Not like they've been part of the ecosystem for
billionshundreds of millions of years or anything.8More like 375 million years, about the middle Devonian period.
Tangentally: for millions of years after plants started using lignin as a structural material the decomposers couldn't break it down very effectively, so for like 60 million years lots of that tough plant material stacked up into deep layers and eventually turned into coal.
10
But car drivers crash into them and hurt themselves sometimes or birds perch and poop on cars. Not worth having trees /s
5If you live some place in a drought, water is an issue when planting new trees.
1
Build covers with solar panels on their roofs. Provide shade and generate money in the long run. Most brick-and-mortar shoppers would be more attracted to covered parking, too.
It blows my mind that an article about shade deserts doesn't mention covering with solar collection systems. We all should expect anything intended to take sunlight should be a photovoltaic surface.
31An increase in the number of solar cells in an area can be useful, but shade cover from trees would have a greater cooling effect on most areas. Trees both shade and provide transpiration cooling. The water evaporating from leaves cools the surrounding air as the water goes from a liquid to gas phase.
42And just like solar panels, trees harvest a part of the energy in sunlight, giving additional cooling to just a shade. And trees are cheaper to set up, even if they may not provide a return on electricity.
Ideally you would have trees on the ground and solar panels on the roofs, to further increase cooling.
12
I really hope Biden pushes something next term that allows promotes solar like the current ev push.
Even better, ban HoAs from banning solar. Fuck that noise.
8Trees should be the first priority, with solar cell shade a distant second. Trees only need water and minor maintenance, are far cooler to be under than a simple shade barrier, provide a lot of benefits like wind breaking and homes for nature to live in that are better for people than artificial structures.
6Solar panels are significant infrastructure investments. Because you don't just need the panels. You need wiring (possibly cooling) to connect them up and, generally, some form of a bigass battery to store the excess power (or the considerably more complex infrastructure to feed that back into the grid).
We SHOULD be working toward this with basically any decent sized office building having panels and storage. But, short term, we need awnings and trees. Trees especially as they do a LOT more than just provide shade.
As for residential homes? Solar panels are expensive and the batteries are too. But, if people can afford it, it is something to consider.
5Pv is now around $30/m^2 wholesale and $60/m^2 retail.
Not much more expensive than a sheet metal roof (far cheaper than a mature tree after all the water and tending), but a sheet metal roof doesn't produce $100/yr worth of electricity.
Tree good. If can't afford tree, then pv obvious choice.
2
Not a bad idea per se but it’s a very expensive solution. We probably won’t be able build enough panels for all of the shade we’ll need for future heat.
Trees are usually the best and easiest solution in most areas, but many municipalities including Tampa don’t take them very seriously. They need space for roots if they’re to provide adequate shade in urban areas.
5Most brick-and-mortar shoppers
This whole article is about residential areas, not commercial / retail ones.
We all should expect anything intended to take sunlight should be a photovoltaic surface.
How do you manage that in neighborhood with preexisting homes?
2My wording was hasty. I only envision that new structures should be expected to come with solar tiles or panels. Like, you spent half a mil on a new house, do an extra 10-20k to have a useful roof instead of a ridiculous summer passive heater.
And yes, you're right, trees should be #1, and the main point of the article was really the disappearance of green spaces and coverage. This brief spot is what was on my mind in my take on it:
Quicker actions could include erecting better shade structures at bus stops or implementing rules for construction to encourage the use of materials that generate less heat in the sun. For example, some cities in the Northeast — including Philadelphia and New York — provide financial incentives for “green roofs,” in which the top of a building is covered with plants.
So I guess I had an "old man yells at clouds" moment.
1
solar panels are usually not that efficient when they're too warm though
1
I live in a nice, heavily treed neighborhood. I always dress wrong, cause it gets so much hotter once I get into the city and open areas.
30One of the biggest shocks moving from the midwest to Los Angeles wasn't the palm trees, it was that there were so few shade trees.
Sure, there were some shady neighborhoods, and there was the very shady Griffith park, but overall, almost no shade. It was nuts.
16Gotta make life tough on those homeless.people. /s
6
I don't understand why city planners love barren plains of asphalt. Throw some greenery in there. Parking lots are so depressing.
22I was rock climbing yesterday on a rockface getting pounded by the sun on a 90° day the entire day I felt sick, tired, and drank a shitton of water and it was not enough. People should value the shade.
21Gotta keep your electrolytes up too. I learned that one the hard way. You don't need to do that in an office, you do when its 110 degrees in the shade and doing physical activities.
5