It was 1999 when Smash Mouth dropped the smash hit All Star, stating “The ice we skate is getting pretty thin, the water’s getting warm so you might as well swim.” Since then, global temperatures have continued to rise, with no end in sight. Political will has been unable to make any grand changes, and the world remains on track to blow through the suggested hard limits set by scientists.
As a result, heatwaves have become more frequent, and of greater intensity, putting many vulnerable people at risk and causing thousands of deaths each year. This problem is worse in cities, where buildings and roads absorb more heat from the sun than natural landscapes do. This is referred to as the heat island effect, with cities often being several degrees warmer than surrounding natural areas. It’s significant enough that experts are worried some cities could become uninhabitable within decades. Obviously, that’s highly inconvenient for those currently living in said cities. How bad is the problem, and what can be done?
The Heat Has To Go Somewhere
Cities like Sydney, Australia are starting to face ambient summer temperatures of up to 50°C, which can be unbearable to exist outside in for more than a few minutes. Worse, surface temperatures can far exceed this level.
Bitumen roads and carparks can hit 80°C, which among other things, makes it very hard to walk back to your car at the beach. Playgrounds have seen even higher surface temperatures, potentially causing burns to unsuspecting children out on a hot day. With temperatures this high, simple solutions like fans fail to make much difference; powerful air conditioning is the key to surviving summer. Many elect to visit shopping centres for extended periods if their homes aren’t suitably equipped.
However, it’s not a problem that can simply be air-conditioned away. The power grid isn’t always up to the strain, particularly in developing countries, and the increased energy use only further drives carbon emissions into the atmosphere, potentially exacerbating the problem. Instead, cities must look to deal with the excess heat in other ways. There are two main ways to attack the problem — reducing the temperature level, and adapting the city to better deal with excessive heat.
Reducing Heat Through Building Materials and Green Spaces
Reducing the temperature level can be done with simple techniques, but achieving a large effect is difficult. Covering roofs with lighter colored or more heat-reflective materials can make a difference, by reducing the amount of heat absorbed by a building and thus re-radiated into the surrounding environment. California has already taken steps in this area, through its Title 24 code that mandates minimum requirements for new roofs and renovations. This has the added benefit of keeping the individual building itself cooler, reducing the load on air conditioning, too. Research is ongoing to develop coatings to reduce the heat absorbed by roads, too. Other mitigating measures involve increasing green space in cities. Trees and grasses can have a cooling effect on their surroundings, however, they must be properly irrigated to do so. With space at a premium in many modern cities, architects are experimenting with ‘green’ buildings covered in plants. Maintenance can be difficult, though, and the plant life can come with a risk of pests. These measures are all useful, but modelling suggests the gains are modest — only bringing down ambient temperatures by a couple of degrees. Surface treatments and greenery could be enough to stop you burning your feet when you run outside to get the mail, but it won’t solve the broader issue.
Designing for Hotter Conditions
Bringing out the bigger guns involves adapting cities to be more livable at higher temperatures. This can involve a broad spectrum of measures. It could be something as small as building shaded shelters at train stations to keep passengers out of the sun, or as extreme as building housing and commercial buildings underground to keep them cooler.
There’s precedent for this, in the Australian town of Coober Pedy. Founded as an opal mining town in 1916, it regularly faces temperatures over 45 °C (113 °F). As the opal boom subsided, many former underground mines were turned into homes, hotels and shops. Buildings underground can be 10-20 degrees cooler than the outside ambient temperature, a major gain with the tradeoff of little to no natural light and more complex construction. It’s unrealistic to expect to sink entire existing cities beneath the Earth, but there are simpler measures available too. Installing efficient air conditioning and good insulation can go some way to making existing buildings more livable, albeit at the expense of higher energy costs.
Regardless of the measures taken, none are cheap or a silver bullet. Some cities will rise to the challenge, while others will see population outflows as residents seek comfort in more liveable spaces. Humanity has abandoned cities to ruin before, and it will likely happen again — but for an altogether new reason this time.
Ahh swimming pools… I remember swimming at the motel at Stovepipe Wells back in the seventies.
All the chlorine was long gone, due to the heat, and most of the swimming pool was filled with long strands of green algae.
It was like swimming in a hot bath, or more accurately, a warm bowl of green stringy soup.
: (
Where’s the problem?
“It will start getting cooler, you just watch”.
Don’t fix what’s not broken, eh?
Thanks to everyone who tries to solve a real problem.
Alas, the energy won’t go away. We can delay the effects by using pools water, but that’s just a short term delay.
How about long term heat storages, how could that be possible?
Long term heat storage isn’t really practical – to store ‘heat’ for the really long term without things actually being hotter means phase change (which is pretty much impossible to do artificially at large scale usefully), medium term you can push heat into large thermal masses (or as one of the recent HAD articles showed phase change ‘fake’ thermal mass), but that only lasts till that mass has equalised with the source – its good for smoothing out changes, but on its own can’t deal with long periods of excess heat/cold..
And if you do something like dumping the heat in the deep ocean or Earths Crust (both terrible idea) it will take a while to make much temperature difference down there, but once you do it for a while the conductivity (and in the oceans case fluid flow) will carry all the heat back up to the surface anyway – so its more of a delay than real ‘storage’ all that energy will get back out, banking up even worse problems for the future…
Now perhaps phase change ‘battery’ could be efficiently shipped around, so all the roasting heat on the city in summertime is used to charge up some battery, to then ship it to the winter freezing cities… But I really doubt that would really work out, and would take designing the city such that its a good radiator to grab that heat/cold and push it around – a complete redesign that just isn’t practical… And super large scale phase change heat stores for your location won’t be either, the scale is just too vast…
Need to get ol’ Muskie to use his boring company to make huge heatpipes north to south.
He tried that called it the hyperloop
At first I thought you were referring to the late congresscritter from Maine; Edmund Muskie!
https://en.wikipedia.org/wiki/Edmund_Muskie
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Say you have a water table that’s 50F 100 feet down, you could drill two wells, or just bury a few 100 feet of pipe below the frost line. In either case you could pump heat into it when it’s hot, and pump heat out of it when it’s cold.
Or at a larger scale every hydro dam would pump water uphill when it’s windy or sunny, and then run the turbine when there’s an energy shortage.
The Swedes did try that.
Problem: the water is constantly flowing in the underground aquifers, so the heat is carried away. Of course you can use it for ground source heat pumps and AC, but trying to store heat there is like bailing water into a well.
Well if you get free cooling in the summer (when it’s above 54F) and free heating in the winter (when it’s below 50F) it’s still a huge win. Sure if you want it 70F in a house then you’ll need a heat pump, but that will be pretty efficient if you are using 50F water to extract the heat from. Much better than burning natural gas, coal, or even just electric resistance heaters.
Yes, but it’s also being done already. Geothermal heat/AC is a thing you can go out and buy already, although it comes at the cost of drilling a fairly deep hole on your property.
The depth of the hole depends on the location, and the amount of heat you want. A couple hundred feet is the usual, to have enough volume that the ground around the hole doesn’t start freezing. If more heat is needed, they drill multiple holes.
I think smarter way than “storing heat” is to “convert heat”. Basically, reverse the fuel process where chemical bonds are broken to generate heat. If someone could figure out a solution to convert the “heat energy” into a form of material that would be stable at ambient temperature we would be able to “store” heat. And potentially releasing it later when appropriate as you mentioned.
As you mentioned, there is a scale issue indeed.
A notable form of “heat conversion” is photosynthesis. The Wikipedia article below about endothermic reactions lists a few examples of endothermic reactions (reactions consuming heat instead of generating it).
https://en.wikipedia.org/wiki/Endothermic_process
That explains one part of cooling effect greenery has on its ambient. So, if it’s supplied water and light, it will sink CO2 and heat.
I have heard of more efficient (than usual) photosynthesis certain plants have. I wonder if it also sinks more heat, and if, and how much more, could biochemists and geneticists boost it?
Solar cells are a type of medium term heat storage. They absorb light energy and turn it into something that isn’t heat.
If you paint them white, they’re even more efficient at not turning light energy into heat.
At those kind of temperatures even they need to be cooled or their efficiency drops. The advertised sales figure for power output are given for solar panels at a temperature of 25°C (77°F).
Too much heat will reduce the output efficiency by a lot. As the temperature of the solar panel increases, its output current increases exponentially, while the voltage output is reduced linearly. The voltage reduction can accurately measure the temperature of the panel.
I thought the thermograph in the article was very interesting. Although the solar panels are black (and it’s pretty unlikely the roof is also black), they are significantly cooler than the surrounding roof.
Could be the conversion of IR into electrical energy is responsible. On a typical low-reflectivity surface, incident photons’ energy is converted to phonons, vibrational energy in the absorber—which we experience as heat.
70% of the visible light hitting a solar cell is down converted into heat (there is no way of getting around the physics of that), so they make the planet hotter and the only natural surface that is that low in albedo is the deep ocean.
That’s a pretty hard argument to make, yes they are low albedo, but compared to almost anything else humans do to a landscape they are no where near the worst… And not even worse than everything natural… So making the planet hotter, well hotter than what?
I’d not call them heat capture devices (unless you are talking the combine solar PV and Hot water systems) and certainly they are not a good method to ‘store’ heat..
You may want to fact check your claims before commenting about things like that, to put it as nicely as I can…
A surfaced road or a parking lot usually has an albedo between 0.25 – 0.15. A solar panel comes in at around 0.1 so it’s technically blacker than blacktop. The electricity is soon converted to heat somewhere nearby, so technically ALL that the panel absorbs turns up as heat.
The usual rebuttal is that the panel saves CO2, which cools down the planet more than the warming effect of the panels, but this is begging the question and missing the point. First, electricity could be produced by other means at far greater efficiency and less excess heat, and second, the solar panels contribute to the local heat island effect because they’re placed directly on the houses and living areas that we’re trying to keep cool.
100% of the light hitting a solar cell is converted into heat.
Someone somewhere nearby will use the electricity and make heat, which is then vented outside, which contributes to the heat island effect.
Oh really, you mean they are not magical entropy free devices? 🙄
There is 1 silver bullet and that’s radiant barrier. It should be mandatory in New houses and buildings where summer temps get high enough for AC. It really makes a difference, I installed insulation after school and when we had a house getting radiant barrier that went up first, it cooled the house by about 10 to 15° by itself! I put some in my car and with an adjustable low pressure cut off my car gets down to 55° 35° at the vent, can’t run AC on low or it will ice up.
Home improvement store use to have a piece of it where you could put your hand inside and it would reflect back your own heat to you.
The radiant barrier doesn’t do anything to reduce the heat of the roof itself, get a lighter color roof.
BTW, asphalt shingles suck (too heavy, they leak, pieces break off), go with a solid metal roof. It will last just about forever.
Make it a reflective metal roof!* to reflect those rays back to space!
*such as galvanized steel -with no dark pigments added.
You need a coating with high emisivity in the IR, like the titanium white paints used on telescope domes.
And I would think the hot ends of heat pumps used for cooling could have reflectors aimed up to space. The totality of heat pumps and AC systems should be an impressive total.
I had no idea that telescope domes were painted white for a reason, or that the paint needed to emit IR!
Thanks!
(I’ve learned something new today, so I can crawl back into my hole)
The really interesting thing is that it’s actually pretty common for telescope domes to over-radiate and cool below ambient. The reason you care is because you want the telescope mirror to be at ambient temperature overnight, otherwise the heating (or cooling) from the mirror itself drives convective currents inside the dome which degrade image quality. So we spend a lot of time figuring out exactly how to heat and cool mirrors (and make them as low mass as possible with high thermal conductivity but low heat capacity).
Black objects radiate heat better. In theory, a body that is able to reflect all incoming light perfectly would not emit any radiation of its own (so-called ideal white body).
This leads to the trick question: what is the blackest object in the solar system? Answer: the sun. It reflects almost no light.
This comment was posted by another [Ren]
Ok but how to solve this?
Like with a motorised shades over the house that follow the Sun.
Or pipes through the garden and circulate air over them.
Or wearable A/C.
Summer is coming, we don’t have much time.
Humanity as a whole doesn’t have much time!
The roofs used in Bermuda might be something to look into: https://m.youtube.com/watch?v=YF7wKayTq8o
Don’t look too long, you might go blind!
B^)
LOL, the sand along the beach is even more blinding.
And don’t look up … EVER … the big shinny fiery ball is up there !!
A lot of cities tends to be heat islands, and the fact that most “modern” houses tends to have large windows to let in tons of light and IR radiation, then houses are fairly good at trapping heat inside. A lot of people install AC units to pump the heat out from the house, but technically this just increases outdoor temps a bit.
One can look into more passive methods of cooling, like storing thermal energy in the building’s foundation, be it warmth for the winter, or cold from the winter to enjoy during summer. (This is somewhat common where I live, but I don’t know about elsewhere.)
Some semi deep wells can also act as a fairly good thermal reservoir. Since the ground temperature a few meters down is typically around -5 to 15 C, or one’s rough year round average temperature. (Though, if one has bellow freezing a few meters down, then maybe don’t poke at the permafrost…)
A lot of the issues with heat in buildings is though something that can be largely aided by wise architectural decisions in how one allows light to enter the building, and how one reflects away unwanted IR from the building. Or how one implements ventilation. Now, some buildings are easier to deal with than others.
Though, at times I think to myself. Considering how a white film/cloth reflects light, then would we see any cooling from covering a large area in more reflective materials?
There is the greenhouses in Almeria, Spain that reflects enough light currently to be a bit cooler than surrounding areas, this is due to the greenhouses having fairly reflective roofs that lets most of the incoming light bunch out into the atmosphere, were a lot finds its way out in space. But I guess that it wouldn’t be particularly practical to cover multiple square km for the sake of “it can get a bit cooler.”
All though, bitumen roofs should probably be replaced with something more reflective. Though, some places have experimented with roof gardens, something that seems a bit more interesting compared to a white painted roof. Since a garden can do more than just be a roof. But there is also solar panels. (They are both a bit reflective, and also convert a fair bit of the light into electricity that can be used elsewhere or just stored for later.)
In the end.
Even if each thing in itself makes a tiny difference, they can add up and over time create a larger difference than one might at first expect. Even if it might take a few years for the change to be noticed.
I agree with your comment(s).
Here in temperate latitudes having an eave (or awning) that extends far enough to block the Summer sun from entering the windows, but short enough to let the Winter sun come in, is also a practical idea (for southern exposed windows here in the Northern Hemisphere).
“Buildings underground can be 10-20 degrees cooler than the outside ambient temperature, a major gain with the tradeoff of little to no natural light and more complex construction.”
I imagine light-piping from surface to underground combined with efficient lighting and brighter interior design. More importantly building underground may conflict with rising sea levels. Maybe the things that need to go underground would be commercial and industrial. Less complaint about aesthetics.
Well, temperature (lower) does not make it enticing to live in.
I visited Coober Pedy and yes, those underground dwellings are a bit cooler … but the AIR INSIDE is a lot STUFFIER AND UNPLEASANT than the hot air outside.
Yes you’ll survive the intense heat but it is not the best solution.
By the way, planting LARGE trees and allowing them to GROW AND MATURE seems the obvious answer but it is clearly ignored … ’cause they blocks the $olar panel$ …
I had no idea where (or what) Coober Pedy is…
https://en.wikipedia.org/wiki/Coober_Pedy
Earth tube cooling and heating of air is a thing, one that has been around in one form or another for centuries.
Make the underground structures watertight and bottle-shaped, where bottleneck is a high-rise above ground, elevated enough to stand above high water level, and with emergency hatch for contingency in case of a surprise wave.
If Fukushima auxiliary generators’ buildings were built on that principle, the name of the place would be probably far less known today.
Interesting article after we have just had our coolest summer in x number of years.
It has often bewildered me with the trend and insistence by developers that you must have a dark colored roof.
I’ve made a point of all my sheds having light colored roofs to minimize heat absorption.
Cities are becoming uninhabitable more from a social aspect than any thing else. Centralization is a liability.
Agreed on all of your points.
And, “Where’s the hack?”
In India they painted some concrete roofs white as a test. 5 to 10 degree Celsius drop inside the building.
Won’t last long though. Someone will designate this roof.
Cities are a problem on so many levels one wonders why we don’t instead just stop living in them. For the most part it seems We started collecting in cities for job opportunities. In doing so we now have blacktop as far as the eye can see, veins of steel gridlocked upon them uselessly wasting fuel and have AC to cool it all down (hey lets add more computers, oh and even more AC). Crime is nasty. Solitude rare. Clean air a memory. Trash, medical waste and even feces in some cases littering the streets.
The list goes on, but I’m left to wonder why after figuring out much work can be done remotely do we continue to try to live in what seems more like a failed idea than something to be fixed. Why don’t we cover it in dirt, plant some trees and be done with it. Live within nature in small towns instead of this concrete nightmare we have made for ourselves.
>work can be done remotely
Cities were originally formed as places of commerce. That’s why the socialists harp about the “bourgeoisie” or the “town-dwellers” who technically don’t do anything for their own upkeep – they just act as middle men between producers and consumers.
Industrialization brought manufacturing into the cities, which created the working class who moved in for the job opportunities. Then de-industrialization removed those jobs and left a class of servants who again don’t technically do anything for their own upkeep – they simply consume resources brought in from the outside by rendering them into services for the purposes of the social elites.
We are no longer doing actual work, but meta-work, such as accounting, finances, design, planning, bureaucracy… which is supposed to help us produce all the real wealth that we need and desire, which is done by nobody. It’s all outsourced and imported. Even the raw materials come from somewhere else since nobody wants to mine or farm them, so there’s a persistent and growing trade imbalance and growing debt since the end of the 70’s. The last time the books were balanced for a few months was somewhere around 1990 and it’s been downhill for the past 30 years.
The reason why we don’t just stop living like this is the political deadlock, where the political left has found that they can remain in power by handing out welfare to the urban poor, so they would not have to seek other opportunities. In exchange, or rather, in the fear of losing these benefits that the depend on, the people keep voting for these politicians and policies that keep giving the society the same drug that’s slowly killing it.
Going against this slow death march is just an instant political suicide. It can’t be done, as the previous administration proved – the growing urban poor will rise up against it, riot, and vote otherwise.
You really can’t put the population of the Earth spread out over the land area the way you are asking for.. There just isn’t enough space (heck in the UK the distance between cities is usually walkable in a day, with lots of rest stop towns on the way…).
Cities are a great way to support a larger population, and reduce costs in production – that mill takes the raw material and refines it to something useful, then the factory next door takes that and makes another step towards the final product – you can get huge numbers of specialist producers near each other able to work very efficiently and with higher quality for it – you can get the previous specialist to adjust to your new parameters and have the parts in relatively no time.
Unfortunately the success of ship, road and rail transit means rather than using the local producer more raw materials are produced and processed vast distances from the consumer, as it can be made cheaper there..
Most of the ‘work’ that can be done remotely is relatively fictional work, in the same sense that money is a fiction we all go along with. It rarely will be work that actually really benefits society, its just the bookkeeping (which is important for a cohesive social structure, but doesn’t actually produce useful product). Also the quality of said work is likely to be lower for it all being remote – you don’t get that water cooler bouncing of ideas, or to wave over the expert in this type of paperwork to figure out what has gone wrong here.
Yes, except the mill and the factory no longer exist. They moved to Bangladesh.
There’s plenty of space out there for people to live. The countryside is practically empty with villages dying because young people are moving out to the cities to study, and then stay there because they find it easier to get unemployment than take some “lowly manual job in the sticks”.
Round here the countryside ain’t empty at all – at least in the evening, when all the commuters have returned… The average age in rural areas not doubt has been going up, but that doesn’t make it empty…
Really isn’t plenty of space, as it is the task of feeding everyone isn’t trivial, plonking millions of new ‘rural homes’ in the middle of the farm land just isn’t viable, nor is bulldozing what few forests remain if you want to have anything resembling an ecology…
Some nations have more space than others, but the population of the planet is in the billions… so lets say something around 4billion individual abodes required (families living together lower the total required, but lots of singles out there too, plus that ‘solitude’ argument above) vs something like 150million square KM of land on the globe.. that ends up cutting each ‘rural’ plot into such a small block you basically have a low rise city scape… And that’s not accounting for land required to actually feed the population, or land not fit for human habitation like the deserts, ice shelf, high mountains…
I’d also say if that is the entirety of your local area I feel sorry for you, yes more industry and material imports than there used to be, but a great deal. But stuff is still made and assembled here – all across Europe really.
The average population density of the earth is 51.8 inhabitants / km^2. Four people in an average household (two adults, two children) would result in each household having roughly 100,000 square meters at their disposal. A fifth to a quarter of that is needed for self-sustaining farming operations, and more than half of it can simply grow forest.
That’s a plot of roughly 316×316 meters for every family of four.
Of course there’s no rule why people couldn’t live in denser communities, and there are certain benefits to that. Still, there is technically enough space that nobody has to live two houses wall-to-wall. With modest sized communities of a few hundred to a few thousand people living in one place, most of the land around would remain empty.
It would mean emptying out places like the UK though. There’s more people than you can sustain by local means. For example, less than 60% of the food eaten in Britain is actually produced in Britain on a net basis. Of course if you WANT to live like sardines in expensive high-rise apartments in a 10 million people mega-city, where you can’t walk far enough in a day to find living nature, fighting for some menial service job at low pay, then by all means.
The point and the fundamental problem is: too many people in the city, not enough proper jobs for them to do, so the urban society has structured around a few large corporations that import all the goods, and the majority of the people take no part in any sort of productive activity, thus remaining as beggars with the power to vote for alms to themselves.
Actually cities are the most efficient places to live, as measured as energy consumed per person. So the question is more how can we make cities more efficient.
Imagine if we could ban cars, which are energy intensive to produce, used infrequently (often 5-10%), and require an amazing amount of space for roads, driveways, parking lots, etc. Use the money/energy saves to build a more efficient public transit system.
Seems a natural to put solar panels on roofs for the double win of producing energy and decreasing the solar load on the roof. Producing things, especially food locally is a big win energy wise as well, there’s been some significant improvements in vertical farms which can produce food efficiently and decrease transportation costs/energy.
>Imagine if we could ban cars,
I may, and none of your dreams would come true because we still need transportation and roads, and thereby some sort of vehicles that need parking lots…
I mean, where exactly would the public transit system go? Would the buses and taxis and whatnot just teleport?
Bikes, busses, and trains are radically more efficient in the use of roads than cars are. With 10x the per lane carrying capacity you could have 10x less roads. There’s a feedback loop, less parking lots and less roads means things can be closer, which makes it even more friendly to public transit. Without cars you don’t need parking lots, or at least radically smaller ones. Current car based cities often have 10 parking spaces for each car, which spend most of the time empty. So the public transit system would go between homes and the businesses, schools, restaurants, airports, etc that people want to go to. That way every tiny restaurant doesn’t require a 25 space parking lots, and ever apartment complex couldn’t have to have 2 parking spaces per unit. It really is shockingly expensive to have cars, it’s just hidden from most people through building codes and city planning. People complain about affordable housing without realizing that there’s a larger square foot requirement for a parking lots for an apartment building than there is for the apartment.
As far as I can see, a bus takes just as wide a road as a car. You’re counting “efficency” by some different metric. Buses, taxis, emergency vehicles, delivery vehicles, the police… you still need roads going just about everywhere, even for people just to walk on.
> So the public transit system would go between homes and the businesses, schools, restaurants, airports, etc that people want to go to.
Either you have to change where “people want to go to”, or you’re just swapping private cars for a massive fleet of public taxis – and where do you park those? When there’s twenty people going to a store, each coming from different directions and saying to the driver “Please wait here”, you still need a parking lot for 20 cars in front of the store. At the end of the day, where do you park the taxis?
Plus, if you assume the cars will be driving around constantly, picking up new customers, they are going to double up the miles per customer just to reach them, whereas each person having their own car only drives the necessary miles, so you’re trading efficiency in parking lots with inefficiency in energy use.
Oh, and don’t forget to change WHEN people want to go. You might get away with pooling everyone going to place X by putting them on the same bus, but then everyone has to go at 7:00 am and leave at 3:50 pm sharp or else they miss the bus.
There’s all sorts of neat optimizations you could do with the traffic if only the people would comply. Of course you can force them to comply, but then you get the effect where all property near your transit stops becomes highly priced and rents go up like a rocket – which also shows up as high commodity prices – while property values elsewhere collapse because people stop going there.
It worked in the Soviet Union because it was a planned economy, so they could say to everyone, “You live here, you work there, you eat your lunch at this restaurant.”, and that was that. Then everyone could ride the trolleybus wherever they needed to go.
The vast majority of road traffic in cities in a single person in a car which is a crazy inefficient way to design a city.
Say you have 1000 people in apartments/condos/whatever that need to get to the city center where most of the jobs are.
Those 1000 people could take a train, subway, or bus and not take much much space on the road, even bikes are crazy more efficient per lane than cars.
With cars you’d need much wider roads with many more lanes, and then you need parking as well. So much so that it starts to dominate the land area of a city and force urban sprawl.
As you might notice as you get closer to the center of a city the number of lanes increases, as does the fraction of building space used for parking lots, parking structures, etc.
Here’s some numbers, for a 10 foot lane cars can move 600-1600 people an hour. Mix in busses 1000-2800 an hour. A bike lane 7500 an hour. Dedicated bus lane 4000-8000 per hour. SIdewalk 9000 an hour. Transitway or rail 10,000-25,000.
Cars insidious, each one decreases the efficiency of all public transport (less riders), which results in less busses per hour, and increases average trip length … which creates more incentives for cars.
>Here’s some numbers, for a 10 foot lane cars can move 600-1600 people an hour. Mix in busses 1000-2800 an hour.
It’s rather irrelevant, since you still need the same amount of road. The bus gets people through faster when it’s full, but a city with a million people trying to move everyone around through the morning rush hours would need something like 20-50,000 buses and it would be a gridlock anyhow – especially since they would all be stopping every 100 yards to drop off and pick up someone. You don’t need many buses to lock up a city center, because they have to stop at designated points and they’re blocking the way for other buses coming in from behind.
Hence why cities with millions of people already can’t live without a metro and/or local rail.
The car drivers are those who come from the outside to the city, and you don’t want to stop or stall them because they’re the ones bringing all the money in…
Don’t forget large car parks full of black cars, all running their AC. Black cars look cool, but they are not…
The science quality of this article is very poor. The ambient temperature does not significantly raise the temperature of a mass if its primary influx is from solar radiation. What is critical is the mass of air flowing over it over time and the humidity, the same physics that impacts on the performance of your computer’s cooling system. Radiation, conduction and convection all play a part in heat transfer and they all operate at different temporal scales with thermal mass having the greatest impact on slowing heat impulses via conduction and radiation being the fastest. Kids in Australia actually do experiments for their STEM subjects around this issue of solar driven heating, it really is child’s play to get your head around it.
Most of Australia’s population live near the coast and the temperature is entirely dependant on the wind direction as it is the mass of the ocean that moderates temperatures which is why NSW and QLD are currently experiencing near constant temperatures day and night, in QLD in particular as there is little wind and the heavy cloud is blocking insolation so the temperature is sitting right at the annual average point. i.e. When it does get hot in Australia it gets very hot, and the records going back as far as white settlement indicate the same factors and levels in the temperature highs and lows as we see today (despite the lies being fed to you and inane arguments implying the manual thermometers are less accurate than digital ones).
The desert regions of Australia have a relatively high albedo compared to forest and are certainly far lighter than the vast swathes of solar panels some fools are proposing, so if the landscape was interfered with things would only get worse. Put the urban regions back to the colors they were originally and they would act as they once did, it is that simple. Just don’t expect the heatwaves and firestorms to go away as they are normal and have been for tens of thousands of years since the more savana like conditions in inland Australia dried up around the time of human’s first entry into the continent. The abundance of megafauna skeletons in the caves of the nullarbor plain are very strong evidence for this.
total layman here, so take me with a grain of salt, but wouldn’t the difference in accuracy have more to do with the ability of the individual to READ the thermometer accurately? ie: 32 F is 32 F is 32 F, whether it’s on a manual thermometer, a digital, or a digital temp sensor attached to a computer, but if the temp. falls between the pips on a regular thermometer, you have to try to guess whether it’s closer to 32 or 33 F.
Not trying to be antagonistic, btw, just spitballing.
Look into noise and accuracy in digital thermometers and their vulnerability to radiation and other effects. Manual reading of traditional meteorology thermometers (which have thermal inertia that makes them vulnerable to noise) is still more accurate. Sometimes “progress” is an illusion based in false assumptions.
ah, I see, so If I’m understanding you correctly, it would be better to have a camera record a trad thermometer than to have a remote sensor that could be effected by background issues? or would it be better to have both for redundancy’s sake?
It would be better to build digital sensors with thermal inertia and noise canceling via redundant modules, all coupled to 24 bit digital to analogue converters. It would also be better to not tell blatant lies about the current digital modules being more accurate than older technology as that destroys the credibility of the people telling the lies and raises a reasonable doubt over their competence and integrity, obviously.
Make dogs ride bicycle powered fans.
Can You Power A House With A Bicycle? https://www.youtube.com/watch?v=xbUxt2x4InE
Power everything like normal? Only a chance if you’re an extreme minimalist. Power up some essentials when the grid is down? Yes, it’s very easy to pedal enough power to run some LED lights and portable electronics.
Best comment.
Could I get a roofing material that changes color based on temperature? Above 70, it’s light colored. Below 40 it’s dark colored. That way it heats in the winter and keeps it cooler in the summer.
Yes. You Win. Who will make this for humanity?
back in the nineties, they used to make toys that would change color depending on different temperature water they were hit with. I actually used to put a toy car with this stuff on it in a glass of water in the fridge, and the color got really intense red (the car was red/white depending on the water temp).
Dunno if they still make toys with this effect, but the tech clearly exists, it’s just a matter of whether it’s practical to implement at a scale where it’s useful, which I have no idea