Though most know such things intuitively, hard numbers help transit designers make their case.
That will help to lower temperatures across a wide area.
https://www.nature.com/articles/s41598-021-01315-1/figures/2
Simple fact is, we’re much more exposed to uv than prior generations.
https://www.sciencedaily.com/releases/2010/03/100316142529.h...
Which corresponds with the ozone layer being about 5% thinner:
https://www.clo.nl/en/indicators/en021819-ozone-layer-1980-2...
Not good (or good for us) but also not a huge huge change, since we stopped the thinning of the ozone layer mostly in time.
The leading causes of death in the UK[1] are heart disease, lung cancer, influenza, dementia, vascular disease (stroke?) and lower respiratory disease. Skin cancer is 1% of cancer deaths, and for melanoma the peak of diagnosis is people 85-89 years old[2]. Considering average life expectancy, people are generally diagnosed with skin cancer a few years after they die.
The partial claim "refrain from going outside which in turn .. is way worse than potential UV induced cancer risks" could be right. Avoiding exercise and increasing your heart disease risk, in the hope that you'll avoid one of the more treatable and less fatal cancers in very late life, is probably the wrong tradeoff. Not to do with Vitamin D or covering up or suncream though. Still, why not do both - cover up and go out, lower heart disease risk and lower your chances of skin cancer diagnosis in late life.
[0] https://www.bhf.org.uk/informationsupport/heart-matters-maga...
[1] https://www.ons.gov.uk/peoplepopulationandcommunity/healthan...
[2] https://cks.nice.org.uk/topics/melanoma/background-informati...
Melanoma causes 1.5 % of total cancers related deaths according to CDC so you are much more likely to die from all the other types of cancer. https://gis.cdc.gov/Cancer/USCS/#/Trends/
However many people only go outside in the context of walking from their car to the door of wherever they are going, and some who work from home can go for weeks without going outside at all. This is a bad thing, you need exercise (though it could be inside), but realistically many people are not getting enough.
https://www.newscientist.com/article/2467926-most-europeans-...
https://www.biorxiv.org/content/10.1101/2025.01.29.635495v2....
"The peoples of Europe are fair-skinned and reddish, because they live in a cold climate and are not scorched by the sun."
Source: Hippocrates, On Airs, Waters, and Places, 5th century BC.
"The physical characteristics of the Germans are consistent: blue eyes, reddish hair, and large bodies."
(Tacitus, Germania, chapter 4)
Egyptian tomb paintings from the New Kingdom (c. 1550–1070 BC) visually represent foreign peoples with distinct skin tones - "Europeans", in the form of Sea Peoples or early Aegean peoples (e.g., Minoans or Mycenaeans), were sometimes shown with light red or pale skin tones.
I am open to this hypothesis (conjecture?), it just lacks supportive evidence. On the other hand, we have ample evidence that agricultural revolution did not "turn people white" in the other regions.
From a cursory study of Wikipedia my rough summary would be: Europe used to be roughly divided in the "Western Hunter Gatherers" (WHG) and "Eastern Hunter Gatherers" (EHG). The WHG typically had dark skin, dark hair and blue eyes, the EHG were typically light skinned with brown eyes. Blond hair may have originated from EHGs in North Eurasia and spread from there. Around 6000 BC farmers from Anatolia (~modern Turkey) started moving into Europe, the EEF (Early European Farmers). Those were typically smaller than European hunter-gatherers, light skinned and dark haired. They migrated North, partially replacing the EHG and WHG, partially mixing with them, and in some places the EHG and WHG simply took up farming. But Easter Europe is less amenable to farming, meaning the dark-skinned WHG diminished the most while the light-skinned EHG and EEF became the dominant groups in Europe's genetic diversity
1: https://en.wikipedia.org/wiki/Early_European_Farmers#/media/...
That all started in the seventies when skin cancer was invented.
heat and light are different factors, even though they mostly come hand in hand. outside, heat is definitely a bigger problem than it used to be, but also we don't spend as much time outside. if heat became a problem people used to take time off, rest during the hottest times of the day and work earlier/later.
(remind me, what was the California "bus shelter" design that was basically an expensive stick and got widely ridiculed on here?)
And, it's even worse than just not working. It's a shelter to provide shade _for women_ that provided almost none. Because apparently shade is now part of the gender wars.
I'm not sure what your point about "gender wars" is. Is this pole too effeminate for a man to be shaded by?
They were referring to this: >Its purpose was to assist female bus riders by offering shade during the hottest hours of the day and providing sidewalk lighting at night.
No gender war, just serving your customers.
TFA address this: "Its purpose was to assist female bus riders by offering shade during the hottest hours of the day and providing sidewalk lighting at night."
It's not about foliage, it's because we like to look as young as possible - or put another way, as undamaged as possible. Sunscreen adds to that a lot, because it mitigates sun damage. At a given age, people used to look much older than we do now, and that is partly because of less sun exposure.
Look up Miyawaki method.
The only downside of female trees is that they shed pods, fruits & seeds into urban environments. But even this might conceivably have some benefits to biodiversity.
https://www.theguardian.com/environment/2020/may/16/how-urba...
Not all trees have separate male and female trees as well. If you only have one type of tree you have no biodiversity and that is almost as bad as no trees.
> Growers’ breeding of purely male diodar trees had created, said Ogren, “something that doesn’t even exist in nature”.
roots destroy water pipes and heave sidewalks and pavement. They can interfere with power lines as well. :(
In so far as improving the comfort of passengers using mass transit the best way to attract more travelers and retain travelers is to run enough busses, trains, subway trains, during rush hour so that the passangers are not packed like sardines ass to dick for 30 mins or more twice a day.
Then cooling inside the inside the passaenger area is also key Sweating like a pig while playing a sardine makes the experience even worse.
Starting work drenched in sweat and the smell of other poeples perfume and cologn is not a good start.
I live in London, we have tons of public transport.
In the middle of the day, outside of rush hour, I use it a lot and it can be really pleasant, particularly suburban rail, you can stretch out a bit, there is often air conditioning, a nice view from the window, etc.
When it's busy I will drive even if it takes longer because my car is guaranteed to have personal space and is clean.
You are wrong about rush hour. You need to provide good service all day, not just during rust hour. People who have good rush hour service and then a "family emergency" pops up mid day when they discover service is bad will go back to driving just in case that happens again. Plus running all day service at the same rates ends up breaking even - between staff willing to take less per hour, and good service enticing people to ride you can generally break even on your costs.
Wikipedia says De Lijn (the company that provides public transport for Flanders) has 2200 busses total. Service could be better but it's not awful either, and that's for a whole region of 6 million inhabitants, so I think your numbers are quite off. A tiny city only requires a handful of busses, a medium one use 50 busses or so.
Dublin has a metro population of about 1.5 million, and has about 1,400 buses (excluding intercity and private services); however its rail and tram systems are, er, inadequate. Berlin has about 1,600 buses for a metro area of 6 million, but of course has a far better rail and tram system.
That's kinda a problem with big capex transit projects: you're spending all this cash to 24/7 fix a problem that only exists for 5-10 hours/week.
Before WFH became a thing here, I just moved my office hours one hour earlier. I went from being sardine-packed to ample seating space. Bonus points for the buses and trains running faster, so my commute was not only orders of magnitude more comfortable, it was also much shorter !
Yes, I understand not everyone can do this, but the point is for people to be spread over a wider time range. Many people don’t have children to get to school and whatnot, a sizable chunk of them could probably move their hours a bit earlier or later.
Providing good service at non-rush-hour is comparatively easy, though; it just has to be relatively frequent. Particularly for buses, the trouble at rush hour is that you can effectively hit capacity for a line; you get buses waiting for other buses to leave stops, and so on.
I am, in fact amenable to this.
How do you establish fairness though?
Best case scenario, say in the US ex-NYC, you will always have 20-40% of people needing to ride their cars because the tails of the distribution are prohibitively expensive.
Nor are these people necessarily wealthy - the economically wealthiest class of people are urban dinks.
So how to do you establish fairness to this 20-40% of people subsidizing the others?
Well, for a start, they're not, necessarily. That thing they're driving on, it didn't magically appear, you realise. Road maintenance and construction is a _huge_ part of total transport spending.
So many problems would go away if we drastically lowered vehicle speeds. For starters we could drive lighter built cars.
We're back to square one - it doesn't cover the $100/hr that a cleaner has to subsidize. Give me a proposal, or an explanation, that makes this fair and Ill agree.
In very dense areas you should have both roads and trains. However only the most dense cities in the world can support that, and then only in their most dense which is often small. For everyone else buses save money over trains.
With buses, you don't include the cost of road maintenance because buses share the roads with millions of other vehicles so the allocable cost is neglible.
And btw neither buses nor trucks nor cars have some constitutional right of way.
Thus the urban infrastructure dilemma.
But fixed transportation infrastructure like trams, metro and other trains have a tendency to define and connect a city in a way that bus routes don’t.
The stops along Tokyos Yamanote line grew into major cities in their own right.
Copenhagens first metro was planned to be financed by building stops in in or underdeveloped areas and selling the land (it failed as the financial crisis of the naughts coincided with the selloff)
Bus routes have never invigorated or defined a city like fixed infrastructure. a part of a city does not become desirable just because you set up a bus stop, but a tram or metro station?
The point about needing good service all day, not just during rush hours, is more interesting. If your hypothesis is that people just want the experience to not be terrible while they're in the bus, more trips during rush hours definitely suffices. You do need a minimum level of service in the middle of the day for the idea to be practical for some people. Surely 15-30min routes are fine though?
Mid day you need better service than rush hour. People going to work generally have a schedule and they have input into it - they can plan their day around when the bus goes. People doing errands in the mid day do not know when they will be done, if there happens to be a line when you go to the checkout you miss your bus. When you are at work you have more control over when you leave and so will always make your bus.
When people see your bus system as a way to get to work and a car is for everything else you can do worse service than when you want people to get rid of the car.
Without looking up the data, off the top of my head.
The bus driver needs a commercial license with air brakes, is a public employee and has benefits.
He has to be making 75k/year + overhead. Let's say overhead is 50%
$56.25 / hr.
Then there's the diesel cost. A large bus must get ~ 10 mpg highway, but a city bus is all stop and go - disastrous for a vehicle as massive as a bus. Let's say it gets 4 mpg.
$4/gal diesel * 30 mph average speed / 4 mpg = $30 / hr on diesel.
We're at $86.26/hr.
You could argue my driver makes too much, and my mpg is too low, but I havent included:
- routine maintenance
- fixing broken vehicles
- cleaning
- amortization
So, play with the numbers if you will; but $100/hr has to be a good, round estimate, for running costs.
Increasingly, most buses would be either electric, or heavy hybrid (ie electric with a diesel generator).
But also, consider the money they take in. My local bus system's buses take up to 100 people. The charge is 2 euro for a journey where the last leg starts within 90 minutes of the first leg, on any mode of transport. However in practice the average journey would be in the 30 min range. So if the buses are constantly full, that's 400 euro per hour takings!
Of course, it's not really that high; the buses are not always full, some people are using monthly or annual tickets, which are cheaper, some people are kids or over 65 or otherwise get cheap or free travel, the trains and trams also have to be paid for, and so on. But it's sufficient that they were actually able to cut the price (it used to be up to 3.50 for a single bus journey); the increased use from the cheaper simpler system offset the reduction in revenue per journey.
This also significantly i creases their overall passenger mile GHG emissions.
Hybrid buses and CNG probably make sense. But I doubt, fully electric buses make sense: as long as dispatch-able power (ie your marginal producer) is a thermal plant you get 60ish% thermal efficiency at best minus transformer and transmission losses.
A bus engine for use in a hybrid can be made more than 40% efficient (miller cycle, high compression, high octane CNG, full throttle PWM operation, etc).
Huh. That doesn't resemble my experience, except for rural/small-town services, which are very much provided as a form of subsidy, not a viable business.
> But I doubt, fully electric buses make sense: as long as dispatch-able power (ie your marginal producer) is a thermal plant you get 60ish% thermal efficiency at best minus transformer and transmission losses.
That's still quite a bit better than diesel engines, where for realistic engines you're talking about 40% _in ideal conditions_, but much worse in stop-start conditions (you will do better with hybrids, granted). Gas also have considerably lower CO2 intensity per thermal watt than diesel does (your fossil fuel electricity production is probably mostly gas in most countries).
But, also, in countries with a lot of unreliable renewables, buses charging overnight can be used as a power sink. For instance, in Ireland, our wind generation can be anything from almost nothing to greater than total system demand; reasonably often, wind turbines actually have to be stopped to reduce output, especially at night. At that point, charging the bus is for practical purposes free, or may even have a modest negative cost (the network will sometimes pay for power consumption).
Which is where hybrid drive trains and PWM comes in. Run the engine at its ideal and only at its ideal with no care for the actual load requested.
Furthermore I mentioned CNG - ie methane. Methane has more energy per CO2 gram than any hydrocarbon and has an insanely high octane number -> it can run an Otto cycle at diesel compression ratios.
Run it as a miller cycle and the thermal efficiency starts to go up even highed.
Really my 40% is a low ball of what is possible in ICEs to not offend anyone's preconceptions. F1 claims to have achieved >50% thermal efficiency in a race engine but Im usually loath to mention that because of their secrecy and therefore lack of indee verification.
And no one talks that lines and transmission is lossy. No one talks that dispach-able power is often coal or oil. No one talks about the environmental and social cost of batteries.
Hybrids ameliorate (the most, btw) just about every aspect of this while minimizing external costs
... Because they're generally not, nearly anywhere. Oil power plants are, in general, rare today nearly everywhere in the world; natural gas really did a number on them. And dispatchable power plants are almost _never_ coal; the startup lead-time is too high (hours at least). Ignoring weird stuff like grid batteries and pumped storage plants, they're nearly always gas turbines.
But the electrical industry makes very careful predictions of the next day's power consumption; that is within a time frame that coal can easily respond to.
Since coal is expensive and dirty, they end up supplying the marginal production. Ie the buses run on coal.
But why keep coal at all though? One advantage coal over has is that you can store massive amounts of energy in a pile just outside the plant. Only nuclear plants can store such massive amount of energy locally.
This storage ability is heavily used in the North East to toughen the grid in the winter where gas pipeline pressure drops due to heating demand.
As to oil, it is actually still used, albeit intermittently and then rarely [1] It is usually used in plants that are primarily non-oil burning. Again, the advantage is that oil is far easier to store than nat gas.
Note that, since oil has a lot more carbon than methane and since oil extraction, at least in the USA, is very energy intensive, oil contribution to GHG is far greater than it's 1% of the energy mix would suggest.
And its all in the margins where the EV bus gets charged.
We've already got decent electric bus options implemented in a number of cities, and they're only going to get better. That's before you consider hooking them up to wires like a sensible transit network.
Municipal fleets often make it a point to use alternative energy with buses, like CNG before batteries were a practical option. They do it for public image, because of the urban air quality issues with old-school diesel exhaust, and for cost reasons.
A more interesting point is pavement. Public buses, garbage trucks, and schoolbuses are some of the most significant non-weather-related causes of road wear, and this is only going to get worse the heavier the axle weight if you try to run long-range battery banks. Road wear scales with axle weight raised to the fourth power. Arguably there is a case to be made for the articulated or even bi-articulated designs if it allowed you to drop axle weight, with significant benefit to the Packed Like Sardines problem. Articulated EVs have a lot more freedom to redistribute the weight and to power individual axles more intelligently.
Hybrid and CNG make a lot of sense though.
[1] Run the math and hybrids come ahead of EVs in personal vehicles for GHG emissions. For buses it would be more skewed in favor of hybrids.
The goal should be more to cover peoples normal transit needs. So plenty of routes with stops very near most people's homes and destinations, and a high enough frequency at most hours of the day and night to not cause too much waiting frustration.
You say that as if it's an unthinkable impossibility. As of 2017 London had 8,600 busses carrying 6.5M passengers every day. Yes a big city needs a lot of buses, so they have a lot of buses. No problem. What would it cost if there were no buses and 6.5M more car journeys every day? And the roads and parking spaces for - what - 1M+ more cars to account for that?
What financial cost to the city for roads and infrastructure and traffic lights and signs and maintenance, what financial cost to the people needing cars, what time cost of humans stuck in traffic, what health cost of less exercise, what health cost of pollution, what accident cost?
Your first half talks about how high the hourly rate to run a bus is. Then in the second half you recommend the same service level for busy versus non-busy times? Seems sub-optimal.
however no matter what it is expensive and you need years of service before people change habbits. Often the expense is so high that 'you cannot get there from here'
However, all of the maintenance around allowing private transport is also a cost. That includes all of the private costs for car ownership. If public transport is a valid option, then car ownership becomes a choice.
A tiny city might need 100 busses, but how many cars does that replace? What is the full cost of those cars? If everyone made a monthly "bus payment" instead of a "car payment" (actually payments when you add insurance, maintenance, ...), I think we'd find the bus system much less expensive.
> It costs $100/hour to run a bus
Googling suggests you can get 40 people on the average bus, but let's say that's 20! Let's be super rough to get guesstimates. California has an average gas price of $4.83/gal[0] and average car is like 24mpg. We'll take that at 60mph and assume you're driving that (mpg is usually worse in cities). So let's say ($4.8/g) * (1/24 g/m) * (60 m/h) = 12. So at half capacity the bus is more than half the price. That's even before we include things like insurance, maintenance, and anything else (like parking fees). Sure, we're super rough, but given how big the difference is I'd be surprised if refining switched the conclusion.
Of course, there's extra convenience of cars, but a lot of time we don't need that extra convenience. A lot of times we're going the same way everyone else is and our convenience becomes inconvenient. There's also lots of extra conveniences of public transportation too. If you've experienced good public transit you probably prefer it in most situations.
I agree, things need to run all day but I disagree that it costs a lot of money. I think the bigger issue is the negative feedback loop. Public transportation sucks, so no one uses it. -> Public transportation can't get more funding because no one uses it. -> No one uses public transportation because it sucks. Unfortunately this is one of those things where "build it and they will come". It won't happen right away, momentum is a bitch, but it can't ever happen without making the investment. And clearly it is actually cheap.
I don't know why so many people seem to think it's one mode of transportation or another? For regular commutes, take public transportation. For emergencies or when time is of the essence, use a car?
Citation needed. Over here, municipalities are trying to find further ways of reducing the cost of public transport. Spending money on comfort is simply not going to happen. Belgium's 2nd largest city's transit system has famously malfunctioning escalators (some of which have been broken for half a decade). The offering is reduced year after year, while prices go up.
I wish things were different.
But I'm sure we'll keep subsidising company cars.
Watering and maintenance are a big cost. Iirc it's about $1000 to plant a tree. $100 for the tree and $900 for the irrigation and labor to plant it. In the first 10 years of the program 2/3 of the 106,000 planted trees were removed due to accidents, storms, not enough water/aging. [1]
[1] https://www.phoenix.gov/content/dam/phoenix/heatsite/documen...
Expecting something like that work without questionable degree of investment to make some tree work survive of its element is contradictory to all the adaptations that make plant life suitable for arid climates (i.e not providing a ton of area to the sun relative to their mass).
The Phoenix report is valuable because it provides lessons that should be avoided going forward: change the laws so property owners are not liable if a tree outside their business hurts someone, don't plant a tree if you can't irrigate it, work with local residents to plant and water trees to save on labor and increase success, etc.
If there's other municipal shade reports I'd love to read them. Helping people find shade is what I do for a living. [1]
[1] shademap.app
ThunderF00t Busted! videos on scammy startups keeping on raising money for this fundamentally unworkable idea:
- https://www.youtube.com/watch?v=vc7WqVMCABg - Zero Mass Water
- https://www.youtube.com/watch?v=Vss1ke5tTvI - Fontus self-filling water bottle
- https://www.youtube.com/watch?v=Vss1ke5tTvI - self-filling water bottle lab experiment what would be reasonably possible
- https://www.youtube.com/watch?v=OfmQcY_sEt0 - WaterSeer part 1
- https://www.youtube.com/watch?v=_gPSyU564Io - WaterSeer part 2
Drinking game: drink every time he says "it's a. de. humidifier."
thanks, I guess. I didn't need a study telling me something I already know and agree with
Look at photos of Tel Aviv. Lush green trees everywhere. Compare it with any other city in the desert. Completely changes the quality of life.
mykowebhn•9mo ago
I would also love to see attempts at providing heat stress mitigation FOR trees.
rightbyte•9mo ago
It has annoyed me alot that buss shelters seem to be built like sun ovens only protecting versus rain and wind.
nottorp•9mo ago
On the other hand, most trees won't protect you from rain.
Maybe it's best to have a shelter under trees.
metalman•9mo ago