this post was submitted on 09 Sep 2024
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I don't really have a horse in this race but this logic doesn't seem legit to me.
How is -17°C really cold weather AND 37°C really hot weather?
One is actively trying to kill you if weren't already dead by the time the weather got that bad. The other just makes your nuts stick to your thighs -- if you're in a humid place.
I'd agree with the logic if 100F was equal to something like 65°C. 🤷♂️
It makes no sense because that's not what the 0 of the Fahrenheit scale is. The 0 point is the coldest an ammonium chloride brine mixture can be cooled to. The 90 point was an estimated average for human body temperature (it was adjusted up over time). These were chosen because the goal of the scale was to provide a way for people to have a defined temperature scale with a range and degree size that could be reliably reproduced without passing around standardized tools. 100 is really hot because human bodies were used as a reference for the high end, but the low end has nothing to do with the human body.
Geometric construction plays a role in there as well: the 180 degrees between the boiling point and the freezing point of water was not accidental.
but like isn't that the whole point of celsius? all you need to calibrate a C thermometer is some water: when it starts freezing it's 0°C and when it's boiling it's 100°C, super simple and accessible.
It's not like "the estimated average human body temperature" is particularly accurate, and surely no matter what you mix into water it won't magically boil at the same temperature regardless of air pressure?
You're totally correct that Celsius is the more sensible scale with easier to replicate reference points (when using water). It was also invented almost 30 years after the Fahrenheit scale and with all the insights gained from that period of technological advancement. In fact in the modern day the Celsius degree size is defined in reference to the Boltzmann constant since Celsius is essentially the Kelvin scale with the numbers moved around.
It also used 100 as the freezing point of water and 0 as the boiling point when originally proposed, which changed after Anders Celsius died because everyone knew that was a weird way to do it.
At what molar concentration? Was it just as much NH4Cl as he could dissolve at ambient temperature and pressure?
As I understand it, yes it was a saturated solution.
0f is pretty fucking cold outside, your nose hairs start to freeze in this weather. It's genuinely uncomfortable and you can die pretty easily if you aren't prepared for it. 100f is similar, anything over 100f and you start to get into straight heat exhaustion and potential heat stroke region of danger. it's really not that bad? Sure if you're like, standing outside doing nothing in the shade, you'll be fine, but do some labor and you might meet the fabled heat exhaustion fairy.
Obviously, when you convert it to celsius, it seems really fucking weird, That's pretty normal for conversions though. Like just to be clear, if you round these numbers, they make more sense. -20 c and "damn it's really cold out" you round up to 40c and "damn it's really hot out"
also im not really sure what you're trying to say, but 0f isn't like, going to kill you kill you, it's not pleasant, but in the right attire you'll be fine. -20 f and you start getting closer, -40f and you really start having to think about it. Are you aussie or something? This scale seems really shifted up to me. "nuts sticking weather" is like 80f and humid here.
I'm saying that 0F is waaaaaaay more dangerous than 100F so the logic of those particular temperatures being the 0-100 ends of the scale can't be explained by how dangerous they each are.
Almost everyone would be fine staying outside for 30 minutes at 100F without no external help (shade, cool drinks etc). Almost nobody would be fine after staying outside at 0F without external help (parka, thermals etc).
To me, with absolutely no data, it feels lie:
So calling 0F and 100F both "really dangerous" and using that to justify them being the respective points of 0 and 100 disingenuous. Like, use Fahrenheit if that's what you're used to - I use it too because that's what I'm used to. But I don't explain the insane system with "it's because the two ends are reallllly dangerous."
idk about that though, i mean maybe if you go outside completely naked, sure. But idk who would be doing that. I've regularly been outside in close to 0f temperature in lighter clothing, it's not pleasant, but im not going to freeze to death within twenty minutes. Plus you can also do physical activity, and as long as you regulate sweat, you'll be fine. Although sweat can be particularly dangerous in colder weather.
i think that's unreasonable though, you just wouldn't be going outside at all in those clothes, in the same way that you wouldn't go outside in 100f weather in a full winter get up. You would literally die.
140f as a relative measure is wild to me, in 140f if you're outside without an air conditioned vehicle (death valley) and you don't have water you will die within about a day. 100-130f is considered "extreme heat" in death valley, which has a website that you can pull up for some relevant information. Once your body is over about 110f internal temperature, you're fucking dead. Unless you have a way to either redirect sunlight from hitting you, and water to replenish that lost from sweat, you die really quickly.
0f isn't considered "extreme cold" that would be something like -40c (or f, they're the same) where basically everything starts to freeze, and i've seen people do overnight camping in that weather. It's perfectly doable, obviously not without gear, but who isn't bringing gear? Hell you can bring a space blanket with you, with the right gear you can easily exist in 0f weather for a prolonged period.
I'm not sure where you're quoting the "really dangerous" from because i just said both of them are "really hot/cold"
did i say this anywhere??? I feel like i'm schizophrenic.
Thank you. That argument bugs the heck out of me.
maybe it's a climate thing? Where do you live, here in ameica it's quite literally the best way to describe it. We see swings below 0f at the coldest parts of the year, and upwards of 100+ in the hottest parts of the year.
So why not make the temperature go to the hottest? Let me guess, 0 isn't the coldest either in America, right? It's just so arbitrary, and pure cope to say it's the best way to describe temperature.
The records are -80°F and 134°F
That's quite an error in a "whole human experience in zero to one hundred" system
All of them are. The decision to use water at all is completely arbitrary. Even Kelvin and Rankine are completely arbitrary: the "width" of the degrees is not defined by a physical factor, but relative to an entirely arbitrary concept.
Technically all arbitrary, but Fahrenheit is definitely on a whole different level of arbitrary.
Celsius - 0 = precise freezing point of water and 100 = precise boiling point
Kelvin - same as C, but shifted so 0 is the precise lowest possible temperature
Fahrenheit - 0 is the imprecise freezing point of some random brine mixture, 100 is the imprecise average body temperature of the developer
That's a myth. It's no more true than the myth that it was the body temperature of horses, or that the scale was designed to reflect how humans experience the weather. (It happens to reflect how humans experience the weather, but this was an incidental characteristic and not the purpose for which the scale was designed.)
The Fahrenheit scale starts to make sense when you realize he was a geometrist. It turns out that a base-10 system of angular measurement objectively sucks ass, so the developer wasn't particularly interested geometrically irrelevant numbers like "100", but in geometrically interesting numbers like "180". He put 180 degrees between the freezing and boiling points of water. (212F - 32F = 180F)
After settling on the "width" of his degree, he measured down to a repeatable origin point, which happened to be 32 of his degrees below the freezing point of water. He wanted a dial thermometer to point straight down in ice water, straight up in boiling water, and to use the same angular degrees as a protractor.
The calibration point he chose wasn't the "freezing point" of the "random brine mixture". The brine was water, ice, and ammonium chloride, which together form a frigorific mixture due to the phase change of the water. As the mixture is cooled, it resists getting colder than 0F due to the phase change of the water to ice. As it is warmed, it resists getting warmer than 0F due to the phase change of ice to water. (Obviously, it can't maintain this relationship indefinitely. But so long as there is ice and liquid brine, the brine will maintain this temperature.) This makes it repeatable, in labs around the world.
And it wasn't a "random" brine mixture: it was the coldest and most stable frigorific mixture known to the scientific community.
This criticism of Fahrenheit is borne of simple ignorance: people don't understand how or why it was developed, and assume he was an idiot. He wasn't. He had very good reasons for his choices.
That was a long way of saying what I said, you just don't see faranheit as ludicrously out of date, while I (and most of the world) do. Live your life as you wish friend. It's a random brine mixture. Maybe it was less random back then, but now it's an arbitrary mixture of water and salts in arbitrary ratios. Deal with it. Fahrenheit sucks.
Every measurement system has had its formal definition changed several times. The kilogram, for example, was once formally defined as the mass of a specific block of metal in France, which was later determined to be losing mass, and thus made a pretty terrible standard. Now, the kilogram is formally defined in terms of the meter and the Planck Constant.
Celsius was once defined by the freezing and boiling points of water, but those aren't actually constant: Fahrenheit's brine mixture is actually significantly more consistent. Kelvin's degree spacing comes from that definition of Celsius, but it it was eventually redefined to be more precise by using the triple point of water: pure water at a specific pressure and temperature where it can simultaneously exist as solid, liquid, and gas. Significantly more accurate, but not enough: Kelvin was redefined in 2019 in terms of joules, which are in turn defined by kg, m, s, which are ultimately defined in terms of the Planck constant.
Celsius is now formally defined in terms of Kelvin. Fahrenheit is also formally defined in terms of Kelvin. Fahrenheit's brine story is just a piece of trivia.
We live on a water planet. The weather we care about is water.
If you look at the overnight low you probably want to know if frost was likely. Guess what Celcius temperature frost happens at.
That factoid makes celsius relevant for about 4 out of the 12 months, and humans lack the capacity to distinguish between 60-100 on the Celsius scale. Anything at those temperatures just feels like blisters.
The high end of 0 to 100 is nice for boiling, when I'm making beer at the boiling stage the number on the scale goes from somewhere below 25 to 100 and so the end point is obvious
We boil water quite a lot, though we often aren't tracking the temperature
Most of the time the temperature scale that's best is the one you know. I don't know of any case where Fahrenheit is objectively best (like Celcius is when water is involved) but I think the best argument for Celcius is it is used in science, so American scientists start a step behind all the others by having to learn a new system. Given neither have any great advantage I reckon it's worth America changing to make things better for American scientists
why not make it more arbitrary? Why not leave metric rules and use something like twelve that has fractions? Because it's nice. It's pleasing having it be 0f and 100f, it's a clean range, and it's also pretty comprehensive in terms of the temperature variance.
It just happens to work out pretty nicely.
You're literally just applying the anti-thesis of the metric system to the question, and asking me why we don't do it that way, idk what you're expecting me to say here.
do celsius users not consider something like -20c to be "pretty cold" and 40c to be "pretty hot" That's equally as arbitrary.
Every time a heat wave brings 100F, the news starts reporting about old people dying. Every time the temperatures reach zero, same thing.
Personally, I can handle the cold much easier than the heat. I get stupid-brain working more than 30 minutes at 95F. Another 15 minutes and I can't catch my breath, lose fine motor control, and start feeling faint. Drenching myself in water - the colder the better - every 20 minutes or so is the only way I've found to be productive above 100F. I feel like 100F is actively trying to kill me.
0F is where it starts getting difficult for me to stay warm without an additional heat source.
Lmao are you a penguin or something? Please tell me that you're exaggerating to make a point and aren't seriously saying that you're capable of staying warm at -10°C (14°F) "without an additional heat source."
I mean, I have clothes. Long underwear? Layers? Coats, gloves, hats, scarves?
They say you can always put on more clothes if you're cold, but that's not really true. Insulation adds bulk, and bulk reduces mobility. Around 0F is where I start to have real trouble wearing enough clothing to stay warm while still being able to perform the activity that has me outside in that weather. Somewhere around 0F, clothing doesn't really cut it, and I need shelter or additional heat.
That's a lot of moved goalposts to justify the weird temperature scale logic but okay.
You've essentially justified that 0F and 100F are what they are because some old people died when it was 100F (most people, including the old are perfectly fine at this temperature all around the world) and because you can manage at 0F while wearing a ton of layers and not need a heat source (do all old people manage to survive just fine at 10F or 20F by just putting on some layers?).
Either way, this pointless conversation had gone on for way too long. Have a good day! :)