Supercooled: Water doesn't have to freeze until -55 F

Nov 23, 2011
The box here is full of liquid water, which is not shown (white). Supercooled liquid water starts to become “intermediate ice” (green) on the way to freezing into ice (red) well below the 32 degrees F that people normally consider water’s freezing point. University of Utah chemists calculated that supercold water finally must freeze at minus 55 F. Credit: University of Utah

(PhysOrg.com) -- We drink water, bathe in it and we are made mostly of water, yet the common substance poses major mysteries. Now, University of Utah chemists may have solved one enigma by showing how cold water can get before it absolutely must freeze: 55 degrees below zero Fahrenheit (-48 C).

That's 87 degrees colder than what most people consider the freezing point of , namely, 32 F (0 C).

Supercooled liquid water must become ice at minus 55 F not just because of the extreme cold, but because the molecular structure of water changes physically to form tetrahedron shapes, with each water molecule loosely bonded to four others, according to the new study by Valeria Molinero and Emily Moore.

The findings suggest this structural change from liquid to "intermediate ice" explains the mystery of "what determines the temperature at which water is going to freeze," says Molinero, an assistant professor at the University of Utah and senior author of the study, published in the Thursday, Nov. 24 issue of the journal Nature.

"This intermediate ice has a structure between the full structure of ice and the structure of the liquid," she adds. "We're solving a very old puzzle of what is going on in deeply supercooled water."

However, in the strange and wacky world of water, tiny amounts of liquid water theoretically still might be present even as temperatures plunge below minus 55 F and almost all the water has turned solid – either into crystalline ice or amorphous water "glass," Molinero says. But any remaining liquid water can survive only an incredibly short time – too short for the liquid's properties to be detected or measured.

How and at what temperature water must freeze has more than just "gee-whiz" appeal. Atmospheric scientists studying global warming want to know at what temperatures and rates water freezes and crystallizes into ice.

"You need that to predict how much water in the atmosphere is in the liquid state or crystal state," which relates to how much solar radiation is absorbed by atmospheric water and ice, Molinero says. "This is important for predictions of global climate."

A Strange Substance

Liquid water is a network of water molecules (each with two hydrogen atoms and one oxygen atom) held loosely together by what is called hydrogen bonding, which is somewhat like static cling. Molinero says that depending on its temperature and pressure, water ice has 16 different crystalline forms in which water molecules cling to each other with hydrogen bonds.

As ice forms from supercooled water (white), some crystalline ice (red) is present but there is much more “intermediate ice” (green) crisscrossing the liquid. Water molecules form tetrahedron shapes in deeply supercooled water, facilitating the ice-formation process, University of Utah chemists found. Credit: University of Utah

Molinero says that "what makes water so strange is that the way liquid water behaves is completely different from other liquids. For example, ice floats on water while most solids sink into their liquid forms because they are denser than the liquids."

Water's density changes with temperature, and it is most dense at 39 F (3.9 C). That's why fish survive under ice covering a pond by swimming in the warmer, denser water at the bottom of the pond.

But the property of water that "is most fascinating is that you can cool it down well below 32 degrees Fahrenheit and it still remains a liquid," says Molinero.

Liquid water as cold as minus 40 F has been found in clouds. Scientists have done experiments showing liquid water can exist at least down to minus 42 F (-41 C).

Why doesn't water necessarily freeze at 32 F (0 C) like we were taught in school?

"If you have liquid water and you want to form ice, then you have to first form a small nucleus or seed of ice from the liquid. The liquid has to give birth to ice," says Molinero. "For rain, you have to make liquid from vapor. Here, you have to make crystal [ice] from liquid."

Yet in very pure water, "the only way you can form a nucleus is by spontaneously changing the structure of the liquid," she adds.

Molinero says key questions include, "under which conditions do the nuclei form and are large enough to grow?" and "what is the size of this critical nucleus?"

Computing What Cannot Be Measured

Molinero says that "when you cool down water, its structure becomes closer to the structure of ice, which is why the density goes down, and this should be reflected in an increased crystallization rate."

Supercooled water has been measured down to about minus 42 F (-41 C), which is its "homogenous nucleation temperature" – the lowest temperature at which the ice crystallization rate can be measured as water is freezing. Below this temperature, ice is crystallizing too fast for any property of the remaining liquid to be measured.

Regular ice crystals (red) are mixed with “intermediate ice” (green) near the end of the process of crystallizing from supercooled water. University of Utah chemists used computers to determine that water, which doesn’t necessarily become solid at its 32 degrees Fahrenheit freezing point, actually can get as cold as minus 55 F before it must freeze. Credit: University of Utah

To get around the problem, Molinero and chemistry doctoral student Moore used computers at the University of Utah's Center for High Performance Computing. The behavior of supercooled water was simulated and also modeled using real data.

Computers provide "a microscopic view through simulation that experiments cannot yet provide," Molinero says.

Previous computer simulations and modeling were too slow and had to last long enough for the freezing process to occur. And it was necessary to simulate thousands of nucleation events to make valid conclusions.

Molinero and Moore devised a new computer model that is 200 times faster than its predecessors. The model simplified the number crunching by considering each three-atom water molecule to be a single particle similar to a silicon atom and capable of sticking together with hydrogen bonding.

Even so, it took thousands of hours of computer time to simulate the behavior of 32,768 water molecules (much smaller than a tiny drop of water) to determine how the heat capacity, density and compressibility of water changes as it is supercooled, and to simulate how fast ice crystallized within a batch of 4,000 water molecules.

The Birth of Ice

The computers helped Molinero and Moore determine how can get before it reaches its theoretical maximum crystallization rate and must freeze. The answer: minus 55 F (or minus 48 degrees Celsius).

The computers also showed that as water approaches minus 55 F, there is a sharp increase in the proportion of water molecules attached to four others to form tetrahedrons.

"The water is transforming to something else, and this something else is very close to ice," says Molinero. She calls it intermediate ice.


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If a microscopic droplet of water is cooled very fast, it forms what is called a glass – low-density amorphous ice – in which all the tetrahedrons of are not lined up to form perfect crystals. Instead, low-density ice is amorphous like window glass. The study found that as many as one-quarter of the molecules in the amorphous "water glass" are organized either as intermediate ice or as tiny ice crystals.

When water approaches minus 55 F, there is an unusual decrease in density and unusual increases in heat capacity (which goes up instead of down) and compressibility (water gets easier to compress as it gets colder, unlike most liquids). These unusual thermodynamics coincide with liquid water changing to the tetrahedral structure.

"The change in structure of water controls the rate at which ice forms," Molinero says. "We show both the thermodynamics of water and the crystallization rate are controlled by the change in structure of that approaches the structure of ."

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User comments : 53

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rawa1
1 / 5 (7) Nov 23, 2011
Computing What Cannot Be Measured
This temperature can be measured. It's actually the temperature, bellow which the ice stops to behave like slippery and wet substance and the regelation of ice stops.

http://en.wikiped...gelation
http://www.youtub...RKhQHDqw
http://lptms.u-ps.../Ice.pdf
Peteri
3.7 / 5 (26) Nov 23, 2011
-55 Fahrenheit?

What?

Gosh, I was obviously under the mistaken impression that this was supposed to be a science news web site!

Why on earth are non-SI units cropping up in such articles?

Is this merely to appease an American audience that are still living in a 19th century time-warp whilst the rest of the world has moved on?
Gdal
2.9 / 5 (17) Nov 23, 2011
The Celsius system is now obviously just as silly as the Fahrenheit system if water doesn't even freeze at 0 degrees C
yosifcuervo
3.6 / 5 (17) Nov 23, 2011
I agree with Peteri, I really wanted to read this article but I couldn't get through it, I find the units offensive
nononoplease
1.8 / 5 (21) Nov 23, 2011
Peteri: Which crap hole country are you from, and how much has the US done to prevent you from murdering yourself?

yosifcuervo: Perhaps you missed the degrees C that was placed next to every Fahrenheit temperature value given?

You can't fix stupid, but you can improve reading comprehension (theoretically).

Signed,
An American (from a land where we can use weird units and still excel far beyond any of you from the mediocre parts of the globe)
Neophile
4.3 / 5 (18) Nov 23, 2011
@nononoplease - American Scientist generally don't use non-SI units either. Peteri and yosifcuervo criticisms of our continued use of outdated units are justified.
Neophile
1 / 5 (1) Nov 23, 2011
*scientists
roboferret
3.3 / 5 (4) Nov 23, 2011
Cool,

(wait for it)

Super cool.
RayW
5 / 5 (3) Nov 23, 2011
They are tracking the distribution of thermal energy remaining in a volume of water, with possible distributions gaussian. As long as the volume contains a total thermal energy capable of 1 liquid phase water molecule existing, the possibility of a liquid phase water molecule is non-zero.
Deesky
4.3 / 5 (19) Nov 23, 2011
What?
Gosh, I was obviously under the mistaken impression that this was supposed to be a science news web site!

Why on earth are non-SI units cropping up in such articles?

Totally agree - this article's a mess, which is a shame because the actual research is interesting.

Not only are they using non-SI units as a preferred unit, but they sometimes decide to give the SI equivalent and other times not. Worse still is the abysmal lack of consistency of notation. We have things like:

55 F
-48 C
55 degrees Fahrenheit
minus 48 degrees Celsius
and no use of the degree symbol °

Grizzled
4 / 5 (12) Nov 24, 2011
Have to agree with Peteri - most of the world will have NO idea what -55F equates to. I had to use a calculator to come up with a number that makes sense.

Isn't it high time our American brethren caught up with tne rest of the world?

Or - are they waiting to lose yet one more Mars probe due to the confusion?
Grizzled
4.4 / 5 (7) Nov 24, 2011
It is actually ironic that, what they use, is imperial system that UK (for one) had abandoned long ago. Yet, those anti-imperial freedom fighters still stubbornly cling to it....Despite the fact that it had already cost them dearly and very likely to cost more...
DarkHorse66
4.5 / 5 (6) Nov 24, 2011
The Celsius system is now obviously just as silly as the Fahrenheit system if water doesn't even freeze at 0 degrees C

What would you prefer; getting your weather report in units of Kelvin...? That system is the only one deemed to have an 'absolute' benchmark, based on the laws of thermodynamics. Water may not freeze at EXACTLY 0 degrees & the Celsius scale may have been arbitrarily defined, but defining the freezing point at 0C & the boiling point at 100C is more intuitive & more straightforward for most people to handle. The funny numbers defining freezing & boiling in the F system are harder to work with.Also: 1 degree Celsius=1 degree Kelvin EXACTLY. No messy calculations required. Here are some quite informative sites. Note the several OTHER units.
http://en.wikiped...ki/Joule
http://en.wikiped...erature)
http://en.wikiped...perature
http://en.wikiped...ute_zero
Enjoy, DH66
88HUX88
4.2 / 5 (5) Nov 24, 2011
Another farenheit vs celsius complaint; the thing I like about Celsius is that I can imagine a line between 0 and 100 at either end of which something significant happens, I can see ice and I can see steam, I can relate to this scale and extrapolate from it. Farenheit is just a number and I have to convert from it, I can convert to Kelvin by simple addition without having to multiply or divide as well. The increments line up with Kelvin too!

On the plus side it generates advertising revenue for farenheittocelsius.com and all such similar sites and stimulates debate (is that the word?) on this site. Please don't change for me, I'm thick, live in the UK and can't think in Farenheit.
Twin
2.5 / 5 (6) Nov 24, 2011
Please, can't we find something more trivial to be upset about?
It's like reading arguments about the ideal fingernail length. Come on! get a life.
djr
4.7 / 5 (6) Nov 24, 2011
"An American (from a land where we can use weird units and still excel far beyond any of you from the mediocre parts of the globe)" Wow nononoplease - way to reinforce stereotypes about loud obnoxious Americans. I am from Uk, and live in U.S. Research (an my experience) would suggest we are not doing such a great job in terms of educational level here - http://www.nytime...nts.html I have a certificate in precision machining - and it amazes me that we still use the old systems of measurement. I can't imagine the cost to U.S. manufacturing to be so out of step with the rest of the world. I think the declining position of the U.S. in terms of science, engineering, economics, business etc. is probably related at least some - to the obnoxious attitude you project in your post.
Bonkers
5 / 5 (4) Nov 24, 2011
My favourite bonkers US unit is for thermal conductivity:
THERMAL CONDUCTIVITY in BTU·IN/FT2·HR·°F
please forgive me if I fall off my chair laughing, and then spend a hour on wikipedia straightening it out into Wm/K
lpeuler
5 / 5 (1) Nov 24, 2011
How does this minimum freezing point depend on pressure? Since liquid water is denser than ice, on would expect the freezing point to decrease (below -48° C) with increasing pressure.
Moonrunner
4.8 / 5 (5) Nov 24, 2011
Aaargh. I know, wasting my breath (or in this case, a handful of electrons) but: Red and Green? Roughly 8% of the population has at least a mild form of color blindness, with red-green being the most common form. For most of these people (anomalous trichromats) these graphs are useless. I realize 8% doesn't seem like much, but in the US that's still over 24 million people. There are web guidelines for creating graphics that anyone can read and understand. In this case the green could have been a dark green and the graphs would have been OK.
antialias_physorg
4 / 5 (4) Nov 24, 2011
You are aware that scientists make these graphs/figures for their own use durinmg the course of the research? It is only after the research reaches a certain stage that these graphs (or screenshots in this case) are then put into a paper (from which physorg then pulls them).

Having a wider public able to view them comfortably comes INCREDIBLY low on the list of considerations when conducting research.

Do you consider to use artificial sweeteners instead of sugar when trying out a new recipe because at some point in the future you might publish a cook book and some of your readers might be diabetic?
toothtrap
5 / 5 (3) Nov 24, 2011
Degrees Fahrenheit are still used in US industry. I work for a chemical manufacturing company in the US. Most of the Plants work in Celsius units, but there are still some that have all of the formulations in degrees Fahrenheit. I prefer °C, but have to be able to think in both formats.
Glyndwr
not rated yet Nov 24, 2011
Dont be one of the arrogant american types criticising the rest of the world as if you are holier than thou. Its a particular anglo-norman strain of culture of thinking you are superior to everyone lol
FrankHerbert
2.6 / 5 (99) Nov 24, 2011
Heh, I'm amazed at the vitriol with regards to units. Of all the things one could rant about over the United States, our choice of units ranks pretty low on the list to me.

I can understand not liking it. I can understand pointing it out.

I agree with Peteri, I really wanted to read this article but I couldn't get through it, I find the units offensive


This I don't understand. Couldn't finish the article? Offensive? What?

On behalf of all Americans, I apologize for our "offensive" units. Get a grip.
nicknirm
3.3 / 5 (6) Nov 24, 2011
Here you go. I came to look at the comments to see what any knowledgeable chemists and physicists among the readers might have to say about the new findings and instead I get anti-American rants from primitive morons. If someone is well trained in the sciences or engineering they would not be confused by the unit system. A simple conversion chart (Google will do) is all you need. If you are so confused and bothered by the unit system that you want to rant, you are scientifically illiterate or it is time to go back to high school science.
pres68y
not rated yet Nov 24, 2011
"lpeuler" asked a good question about freezing.
Anybody care to discuss it, rather than units?
FrankHerbert
2.3 / 5 (83) Nov 25, 2011
It's ironic just how "American" the anti-American sentiment in this discussion is. Just how there is the stereotype of the American offended at having a foreign language detected by any sense, evidentially there seems to be a similar stereotype of the offended metric system user.

After thinking about this for a bit I'm assuming societies which use only the metric system don't require their children to do unit conversions in school. (Why would they?) This hadn't occurred to me. Maybe these people are actually at a total loss as to the meaning of measurements, i.e. what they are even measuring. In a chatroom I was in recently a Brit with a nasty case of nationalism got quite flustered at the term "gallon". I guess you can't convert something when you don't even know what it is measuring.

Being "bilingual" in these systems from years of exercise in math and science classes, it really never occurred to me that someone might actually not be able to use imperial units, not just too lazy.
antialias_physorg
4 / 5 (4) Nov 25, 2011
[q9I guess you can't convert something when you don't even know what it is measuring.
Yes. Why would we start to learn about every backwater unit of measurement? Might as well learn about what a stone, a reaumur, a cup, a Siemens, a candela, ... is.

SI units are there for a reason (note the "I" in SI). If you want to publish internationally then you'd better use them.
Isaacsname
not rated yet Nov 25, 2011
Interesting article and research, I was kind of under the assumption these things were known, or predictable with phase diagrams ?
rawa1
1 / 5 (1) Nov 25, 2011
Interesting article and research, I was kind of under the assumption these things were known, or predictable with phase diagrams ?

Phase diagrams are constructed from experimental data, this is ab-initio calculation study. For example, no phase diagram explains, why just the water can be superheated/supercooled so much...
FrankHerbert
2.3 / 5 (82) Nov 25, 2011
[q9I guess you can't convert something when you don't even know what it is measuring.

Yes. Why would we start to learn about every backwater unit of measurement? Might as well learn about what a stone, a reaumur, a cup, a Siemens, a candela, ... is.

SI units are there for a reason (note the "I" in SI). If you want to publish internationally then you'd better use them.


For one, I thought it was obvious in my post that I thought they *shouldn't* have to learn imperial units. It just hadn't occurred to me that they hadn't.

This is an "international publication" and not a website on an American domain, right. Also, "backwater" is part of the vitriol I'm talking about. Just like an American that gets flustered at a foreign language, you get flustered at imperial units because they make you feel dumb. You then project that dumbness on other people by calling them backwater. The behavior you are demonstrating is ugly and very "American". Have fun with that.
antialias_physorg
3.7 / 5 (3) Nov 25, 2011
Just like an American that gets flustered at a foreign language, you get flustered at imperial units because they make you feel dumb.

I dunno. I learned all these units at some point in my life (yes, I know what a mile, gallon, ounce, Reaumur, Siemens or even a 'barn' is and how they are defined - go figure). It doesn't make me feel dumb not to know about some other units.

It's just a matter of bad style to publish something internationally and not put it in international units. The author is only hurting himself (his paper is basically unciteable).

It's sort of funny how something as anti-monarchy as the US still uses 'imperial' units, while the monarchy that actually originated them has dropped their use.

As for the term 'backwater': Liberia and Burma certainly are backwater countries. The US being the only other country that still uses these units.
ZZMike
1 / 5 (1) Nov 25, 2011
yosifcuervo and Peteri and Deesky: This is nit-picking to an extreme degree.

Evidently you'd be happier reading the Belgian Journal of Scientific Research.

Antialias: "It's just a matter of bad style to publish something internationally and not put it in international units." Try reading the article again. Celsius units are there.

And why not Kelvin?!?!

"Backwater unit... a stone, a reaumur, a cup, a Siemens"? That's the most flagrant case of "ad absurdum" argument I've heard all year.

The mark of an educated man is how much he knows about the world. (More than half the world cooks using cup measurements.)

There's probably one or two comments on the physics involved, but the wailing and foot-stamping from the Society to Stamp out English Units is overwhelming.

To quote Shakespeare (another Englishman) "Get thee an Life".

antialias_physorg
3 / 5 (2) Nov 25, 2011
(More than half the world cooks using cup measurements.)
But most cup sizes in different countries are not interchangeable (then again: for recipes it isn't as important to have an eye on the international audience as it is for science)
FrankHerbert
2.4 / 5 (81) Nov 25, 2011
Antialias, this is a site for laypeople, predominately visited by Americans, not a scientific journal. Please find me a journal article by a well respected American scientist that uses imperial units and I will concede your point, otherwise you have none and are using this as an excuse to make cheap nationalist shots at Americans.

Nationalism is ugly even when practiced against a nation known for its nationalism. When you use insults you cross the line into nationalism. You can make your points without resorting to nationalist insults. Try it.
antialias_physorg
3 / 5 (2) Nov 25, 2011
Hmmm..I just checked to be sure: but I can't really find any argument by me that was aimed at any one particular nation. Nor can I find any insults (I did make a comment about something I find funny - but I don't know how that can be construed to be taken as an insult)

There's plenty to criticize about the US, never fear, but in this thread I didn't.

So what's your gripe?
Callippo
1 / 5 (1) Nov 25, 2011
Why is it so big problem? How do we want to understand the contemporary theories full of math, when the simple unit conversion makes so big trouble for us?

http://lmgtfy.com/?q=-55 F in Celsius
Deesky
5 / 5 (3) Nov 25, 2011
yosifcuervo and Peteri and Deesky: This is nit-picking to an extreme degree.

I didn't think I was nitpicking, it's a genuine grievance.

Evidently you'd be happier reading the Belgian Journal of Scientific Research.

I don't follow, why would that be?

And why not Kelvin?!?!

Kelvin is commonly used too, but its use is preferred when dealing with very low or very high temperatures. But even then, Kelvin units have the same meaning as do Celsius degrees.

The mark of an educated man is how much he knows about the world.

And an educated man would know to use a system of units which are an actual International Standard - he would not persist with cubits!

There's probably one or two comments on the physics involved, but the wailing and foot-stamping from the Society to Stamp out English Units is overwhelming.

That's because it's so arcane and in this piece, it's a mish-mash of permutations.
jsa09
5 / 5 (2) Nov 25, 2011
You guys discussing units need to consider a few alternates.

I weigh 12.5 stone and used to fill my car with fuel measured in gallons but now use litres. The gallons used in the past were imperial gallons which were bigger than American gallons.

I don't know why there was two different sized gallons in use have to ask the Americans that one.

The roads outside my fathers farm were generally fenced on both sides whereas the fences were a chain apart.

These days we don't use chains, fathoms, furlongs (although a few racetracks are still furlongs long), or rods. So I guess farenheit, miles and gallons can all get lost too.
FrankHerbert
2.3 / 5 (81) Nov 25, 2011
There's plenty to criticize about the US, never fear, but in this thread I didn't.


As for the term 'backwater': Liberia and Burma certainly are backwater countries. The US being the only other country that still uses these units.


I didn't call A backwater. I just said B and C are and A happens to be just like B and C on the subject at hand. I'm not insinuating anything at all. Please excuse the shit protruding through my grin.
antialias_physorg
not rated yet Nov 26, 2011
Would you actually argue that being the last to use an outdated modus operandi does NOT qualify as 'backwater' (for that particular issue)? I thought that was what the whole definition of what backwater was.

ugosugo
not rated yet Nov 26, 2011
I see that God-feared universities still consider the metric system an option!
and7barton
not rated yet Nov 26, 2011
Listen - if Peppercorns, Ells and bloody Groats were good enough for my great-great-great-great grandfather, then they're good enough for ME.
FrankHerbert
2.4 / 5 (85) Nov 26, 2011
It's just as intellectually dishonest to call the United States a backwater country over its system of measurements (the metric system has been the official system of measurement in the US since 1895 believe it or not) as it is to claim the United States is the only country practicing anything worthwhile since we went to the Moon or any other number of scientific achievements that if I were to list them in this context would be nothing more than dickwaving, so I won't. The United States is very obviously not a backwater country, despite its vulgar units.

I would prefer to see the metric system universally adopted. Using imperial units doesn't bother me either.

Nationalism bothers me.
Sonhouse
5 / 5 (1) Nov 27, 2011
-55 Fahrenheit?

What?

Gosh, I was obviously under the mistaken impression that this was supposed to be a science news web site!

Why on earth are non-SI units cropping up in such articles?

Is this merely to appease an American audience that are still living in a 19th century time-warp whilst the rest of the world has moved on?

They did say -55F (-48C).
rawa1
1 / 5 (1) Nov 28, 2011
Why on earth are non-SI units cropping up in such articles?
The SI units are Kelvins, not degrees of Celsius. IMO most people here would be confused with Kelvins in the same way, like with Fahrenheit degrees.

My point is rather different: the only insightful post dedicated to physics (the first one) was downvoted, which the rest of thread is filled with silly remarks about unit conversion. I don't know, who you actually are, but the intelligence of comments isn't very high right here. I hope, it's a product of silly educational system oriented to formal memorizing and units conversions rather than the result of intelligence of posters, but I can be wrong.

Try to work on it systematically, because the level of PO discussion can be only as high, as the level of its posters is.
guptm
5 / 5 (1) Nov 28, 2011
Original paper published is in Kelvin unit of temperature. There is no mention of Fahrenheit at all in the paper.

So, why did the writer of this article introduce Fahrenheit in the first place? Do people understand Fahrenheit better than Kelvin and Celsius?

225 K = -54.67 degree F = -48.15 degree C

K is SI unit, others are not. Degree is used with F and C but not with K.
DarkHorse66
5 / 5 (1) Nov 28, 2011
It's just as intellectually dishonest to call the United States a backwater country over its system of measurements (the metric system has been the official system of measurement in the US since 1895 believe it or not) as it is to claim the United States is the only country practicing anything worthwhile ...The United States is very obviously not a backwater country, despite its vulgar units.
I would prefer to see the metric system universally adopted. Using imperial units doesn't bother me either.
Nationalism bothers me.

I'm glad to hear a moderate voice in this argument.But, this then does beg the BIG question...If the metric system is official in the US, then why are they having such issues making its norm a reality??No other country which has introduced metrics has had this problem. No disrespect intended, but perhaps this is where backwater insinuations might have at least some validity.My understanding is that even Canada has gone dual, to ease this.(Road signs,etc)DH66
FrankHerbert
2.4 / 5 (79) Nov 28, 2011
The metric system was legally adopted by Congress in 1895, but admittedly it never caught on in common use.

I'm sure it's a number of factors. The main factor probably being the federal style government of the United States. In a country with a unitary government, or less layers of government, something like changing every road sign would be a much less daunting *political* task. In the US with it's 10's of thousands of individual governments, getting everyone on the same page is virtually impossible.

It's a shame and the metric system is obviously preferable, but I don't think this issue would be worth scrapping our form of government over (not saying it shouldn't be done though). It doesn't affect anyone in their daily lives in a meaningful fashion. I would not be angry if the temperature was presented to me in Celsius, or some strange unit I'd never heard of. I'd simply deal with it.

The lost Mars probe is a shame, but other than that I don't see how this has affected science.
bluehigh
1.2 / 5 (34) Nov 28, 2011
It's like reading arguments about the ideal fingernail length.
- Twin

Would that be length in 'inches' or 'centimetres'?

DarkHorse66
not rated yet Nov 29, 2011
I'm sure it's a number of factors. The main factor probably being the federal style government of the United States. In a country with a unitary government, or less layers of government, something like changing every road sign would be a much less daunting *political* task. In the US with it's 10's of thousands of individual governments, getting everyone on the same page is virtually impossible.


That could be legislated for at a federal level(as long as it is worded right), or does it actually need an act of Congress to enact what is already official?... On the bright side, many sleepy towns in the middle of wherever might actually benefit from being forced to replace worn out ancient road signs ;)
The lost Mars probe is a shame, but other than that I don't see how this has affected science.

This is going back a few years, but I actually recall that there was once a joint mission between Europe and US, where the Americans provided the wrong sized parts....cont
DarkHorse66
not rated yet Nov 29, 2011
cont....for a space project because they failed to notice that the units for sizing weren't in imperial. It became a case of 'what colour is red' on an international scale, as well as causing additional costs. Perhaps one of you guys remembers more about this. As far as the Mars probe being a shame; those things don't exactly come cheap and with the NASA budget squeeze, is more likely to get entire projects canned for lack of money, rather than having more money thrown around. The US is now dependent on hitch-hiking with the Russians in order to merely get to the space station. That says a lot. Unfortunately (in this sense) the generosity of the Kennedy and Reagan eras is long over :(
I'm sure though, that there are (have been) other incidents where the disparity in conventions has caused 'issues'. Needlessly. Cheers to all, DH66
FrankHerbert
2.4 / 5 (79) Nov 29, 2011

That could be legislated for at a federal level


States' rights is a problem here. I'm assuming the national government could legislate a change of signage on national highways, but not local roads. Those are maintained by the state, and if okay by the state, the local municipality. So the problem you would run into if a change was legislated would be different signage. Some states would probably adopt the metric system. Other more jingoistic ones would keep the imperial system out of some combination of tradition and spite.

If you think it's a problem among nations, imagine how many manufacturing errors would plague the US internally.

There just isn't any political capital to get it done. The people who don't oppose it don't care (I'm probably a good example). The people who would oppose it would flip their shit. It'd be denigrated as unamerican, European, communist, probably even homosexual. It would be political suicide for whoever proposed it. The right would crush them.
DarkHorse66
not rated yet Nov 29, 2011
On a more serious note, Anders Celcius didn't choose to calibrate his scale against water entirely arbitrarily.
http://en.wikiped.../Celsius For the ones getting their knickers in a knot about 'inexact' boiling points; note the following extract; "an altitude change of only 28 cm (11 in) causes the boiling point to change by one millikelvin." (A Q. for you: is seelevel measured from high tide or low tide land? Tide level changes are mostly greater than 28cm)NOTHING CAN be that exact.There is ALWAYS a level of uncertainty.Water happens to be a key standard of conversion for a number of properties because of its unique properties http://www.engine...290.html
10cm cubed = 1 litre = 1kg = density of '1'
A more in-depth article: http://en.wikiped...of_water
Even more(the COOLEST :)phase diagram chart in there): http://en.wikiped...ta_page)
Everything you(n)ever did want to know about H20 :)DH