Talk:Fahrenheit

Ref 13

Currently reference 13 is given for reducing the number of negative signs included in averaging temperatures, as for weather data or whatnot. In the version available from Univ of CA library in PDF these pages and indeed the general segments of the book are discussing the failed conversion from aune to meters in the French textile industry of the 19th century. Furthermore, the presence of a large number of negative values is not a problem for computers or modern calculators and one rarely does such things by hand nowadays so I believe that this reference should not be applied to that sentence and that the sentence should be worded so as to suggest a historical reason rather than a valid modern reason the US hangs on the Fahrenheit scale. That paragraph in the Wiki article is indeed of poor quality. The suggestion that decimal values are needed in Celsius but integer Fahrenheit values are adequate for non-technical work is ridiculous. In international weather forecasts the temperatures are provided in integer Celsius values and given the unpredictable nature of weather, even these larger units are rarely correct when rounded to the nearest degree Celsius. The notion that one would need the granularity of Fahrenheit in weather is therefore baseless. 83.201.249.94 (talk) —Preceding undated comment added 23:06, 28 October 2011 (UTC).

Cmt

For Wiki articles, there's a handy template to display the same temperature in two units, e.g. {{convert|18|°C|°F|1}} yields 18 °C (64.4 °F). Also, Google provides a conversion tool -- Matthead ^discuß!     O       01:12, 30 September 2007 (UTC)

Talk

Hi! 0F it was originally the lowest temperature of mixture of ice, water, and ammonium chloride, a salt in Gdansk - Poland during winter 1708/1709. 100F it was temperature of his body. He had a fever this time so 100F is 37,8 Celsius. Source - Polish Wikipedia. — Preceding unsigned comment added by 195.1.54.189 (talk) 00:07, 12 October 2011 (UTC)

ok..... —Preceding unsigned comment added by 67.188.184.148 (talk) 23:40, 11 April 2010 (UTC)

Why is the temperature conversion table backwards from the Celsius and Kelvin pages. On those pages it has the To Find, and From columns in reverse. Would their be a standard way to format them?

Why does it stand 0F = extremly cold? That's not cold at all! Temperatures here where I live are in the winter often way below ~-30C, sometimes even -40 to -50C.

OH GOD! I hate that argument. Just because it gets colder where you are from, does not mean that 0 degrees Fahrenheit is not cold. If you really think that 0 degrees Fahrenheit is not cold, then why do you still wear winter clothes when it is 0 degrees Fahrenheit and not shorts and a tank top? —Preceding unsigned comment added by 72.37.244.68 (talk) 16:50, 9 August 2009 (UTC)

0F is actaully colder than 0C. 0C would be 32 degrees Fahrenheit. 0F = -17.8C. So when you say it gets -50C where you live, that would be -58F. —Preceding unsigned comment added by 67.185.42.86 (talk) 08:21, 20 September 2010 (UTC)

---

It Says: allowing him to mark degree lines on his instruments by simply bisecting the interval six times (since 64 is 2 to the sixth power).

What the heck does that mean? Phillybiggs 12:47, 7 March 2007 (UTC)

We have an article about that: Bisection. Shinobu (talk) 12:36, 3 June 2008 (UTC)

Disambiguation

Not sure how good an idea it is to have a disambiguation page here - have you looked at the multitude of pages that link here, all for the temperature scale meaning? Someone's going to have to fix all those links if this is to remain a disambiguation page. Mkweise 03:28 Mar 7, 2003 (UTC)

I agree and I'm moving it back. The graphics API is not at all famous enough to cause a reasonable ambiguity over the use of "Fahrenheit". --mav 03:51 Mar 7, 2003 (UTC)

Done. I gave the API a disambiguation block even though very few people will actually use it. --mav

while we're at it, there's Fahrenheit by Dior (kidding) -- Tarquin 10:44 Mar 7, 2003 (UTC)

Contentious historical details

I want to suggest that the selection of zero degrees was the temperature at which Fahrenheit found that salt water in the harbor would freeze. Saying it was determined by a "mixture of snow and salt" doesn't make sense, because the snow could be at 32 degrees and and the salt could be warmer still. I don't believe that mixing them will make the mixture get colder! —Preceding unsigned comment added by 198.92.66.172 (talk • contribs)

Combining snow and water at 0 C will cause them to melt (a fact well known in winter-afflicted areas). According to the relevant accounts, Fahrenheit took snow (being near-pure water) and mixed in as much salt as he could. That produced saturated salt water, which he cooled until it froze. He set that as zero. Ocean water has much less salt, and begins to freeze at lower temperatures. Michaelbusch 23:04, 27 February 2007 (UTC)

Other factors contributing to selection of reference points

Has anyone else noticed that by the current Fahrenheit scale, a freezing temperature of 0 degrees for pure water would mean a core temperature of 66.6 degrees for a human, an uncomfortable number for churches during his time. Think about it... Freezing and boiling separated by 180 degrees but neither at 0 or 180.

I removed this for now:

Other accounts assert that Fahrenheit's goal was to produce a scale where the coldest and warmest air temperature extremes in Europe would be zero and 100 degrees, respectively, because the scale was devised to measure air temperature moreso than for laboratory experiments. It follows that his choice of salt water's freezing/melting point and the healthy human body temperature were just convenient, stable, consistently measurable reference points that would always be near these values.

Some accounts go further and say that the scale was devised with each degree being the minimum change in air temperature that a human could perceive.

Checking three encyclopedias, the top Google hits and the Dictionary on Scientific Biography could not verify either claim. AxelBoldt 20:45 Mar 20, 2003 (UTC)

Both claims were in a middle school science textbook in the early 1980s. As punishment for talking in class and tipping my seat, I had to manually transcribe several pages from it, including one about the Fahrenheit scale. Of course, I don't have the textbook now, and am recalling it from memory. But before adding those paragraphs, I spent about an hour trudging through articles that I found through Google. It was surprising how little consensus there is among the stories of Mr. Fahrenheit. However, I did find a "verification" of the first claim (i.e, an article stating that the purpose of the scale is believed to have been for common air/water temperature measurement). I felt that it should still be phrased in a manner that clarifies that there's very little reference material to back up any of the claims. I'm not terribly attached to the phrases either way; I just thought they should be mentioned in a "some say, others disagree" kind of way before someone comes along and plops them in as indisputable fact.mjb 20:32 Mar 22, 2003 (UTC)

The claim that I heard

I heard that Mr. Farenheit decided to calibrate his scale with freezing water at the low point and the healthy human body at the high point. Unfortunately he was a bit light headed that day, and didn't think the process of taking the measurements though. He went outside on a Winter morning and took a reading of the temperature of the snow on the ground and called that 0. Then it took his own temperature, and unbenounced to him, he had a fever that day, explaining why he didn't think though his process for "freezing water." Like i said, i heard that story second hand, and i don't recall the source. take it however you want :) -- — Nate | Talk 05:46, Jun 14, 2005

(UTC)

It's inaccurate to say that Fahrenheit's goal in establishing his scale was to avoid the negative temperatures given by Romer's scale, since both scales have more or less the same zero! More accurately, he probably wanted to avoid the fractionnal temperatures which were common with Romer's scale ( plain water freezing at 7.5 degrees for instance).

Fahrenheit's name

When signing for Royal Society Fahrenheit wrote: Fahrenheit, Polonus. AM

Anyone care to comment on this? — mjb 07:21, 4 May 2005 (UTC)

Fahrenheit's Nationality

If Mr. Fahrenheit was born in Danzig now Gdańsk, and signs his name as abovementioned (Polonus: Pole in Latin), it leaves much doubt as to his actual (albeit perhaps adopted) nationality.

— Clarification needed. Luceus

No comments about his name, but the article does state that Fahrenheit was a physicist. you would be hard-pressed to find a Fahrenheit biographer that identified him primarily as a physicist by trade. Notably, the article about Daniel Fahrenheit on this same website does not mention that he was a physicist, nor that he ever studied physics explicitly. I've read that Fahrenheit invented his scale while working as a maker of glass instruments in the Netherlands. —Preceding unsigned comment added by 141.20.245.59 (talk) 09:15, 13 August 2008 (UTC)

Adoption and abandonment of Fahrenheit system

There is still very little info in the article about which countries adopted the Fahrenheit scale, when this occurred, and when the scale was officially abandoned. If anyone has any info, even for a single country, please add it to the history section. — mjb 07:21, 4 May 2005 (UTC)

Avoid implicit criticism of countries that use Fahrenheit

Yes, the USA, and Jamaica, apparently, are the last holdout for Fahrenheit for everyday, non-scientific temperature measurement, but Wikipedia editors should not parlay their annoyance at this situation into non-NPOV prose. As of today, I've toned down the text in this article and in the Celsius article so that it reads less like commentary. There is no need to mention that Europeans find it "puzzling" that the USA is one of a "declining number of countries" "still" using this system, phrases which together imply fault. - mjb 00:47, 10 Apr 2004 (UTC)

The article gives the impression that many European countries only switched to the Celsius scale in the 1960s. Is that correct? (I would have thought that only a few European countries ever used Fahrenheit, and that most of them adopted to Celsius (centigrade) much earlier, perhaps still in the 19th century. France in particular must have skipped straight from Réaumur to centigrade.)
Jorge Stolfi 07:12, 13 May 2004 (UTC)

I must add that Canada still uses (in part) Imperial measurements such as the Fahrenheit (see here: Metrication_in_Canada). Most of the conversion from Imperial to Metric was done in the 1970s and 1980s, but imperial units are still taught in elementary classes, highschools, and universities. cheater 16:14, 15 February 2007 (UTC)

Only old people use Imperial measurements in Canada. Elementary schools only mention Imperial when teaching how to convert to metric. Any high school or university worth anything has little to do with imperial. Honestly, Canada should outlaw the imperial system. —Preceding unsigned comment added by 68.144.177.83 (talk) 06:49, 13 November 2009 (UTC)

asians ARE puzzled by the Americans and their use of non-metric units in general. I grudgeingly accept to do the maths if I am in the US, but when US Tourists not only refuse to understand metric units when in Europe, but allow themselves to yell at you for refering to temperatures and distances in metric units, I get PUZZLED. Okay, let's put into the article that the US, with less than 5% of the world's population, now is the only country using the Fahrenheit system. Osopolar —The preceding signed but undated comment was added at 22:02, August 26, 2007 (UTC).

Only old people use Imperial measurements in Canada? Entirely laughable! As a 25 year old, I measure my height SOLEY in feet and inches, weight SOLELY in pounds, and cooking temperatures, etc, SOLELY in Fahrenheit. Carpenters, engineers, private signage, etc also typically favour Imperial. In fact, and apart from the United Kingdom, Canada is probably the most non-official (and if you REALLY want to get technical, Imperial units are still legal in Canada: http://laws-lois.justice.gc.ca/eng/W-6/page-2.html#anchorbo-ga:s_4) "Imperial" country on Earth: http://www.bwmaonline.com/Imperial%20Origins.htm 173.183.73.128 (talk) 06:23, 15 January 2011 (UTC)

Being an American currently living overseas, I have found it difficult to get used to Celcius, and overtime I have thought of some clear advantages to Fahrenheit when discussing the weather, possibly explaining why Americans have been so resistant to a change to Celcius. I have therefore added an "Advantages in weather readings" section, as I feel that this article should discuss advantages (as well as disadvantages) to the scale. I would welcome a disadvantages section as well.Ds9kicks (talk) 09:05, 19 March 2008 (UTC)

Hello... thanks for the contribution. Unfortunately, the text is primarily opinion, unsupported by any references, and has had to be removed. Please don't take this as a comment on the quality of your opinions, as that is not the issue at hand. The problem stems from the fact that it is your opinion, and as doesn't meet Wikipedia's policies and guidelines for inclusion. (If you can find a documented survey or some scientific research that draws such a conclusion, that would be more appropriate.) Please feel free to ask if you have any questions about this. --Ckatz^chat_spy 09:19, 19 March 2008 (UTC).

Imperial measurement is not taught in Canadian schools. I can't even imagine an elementary/secondary/university science program in Canada using anything other than metric. The reference on here that Canadians use F for water temperature is certainly odd and incorrect.

Imperial measures certainly are taught in Canadian schools. See Ontario's reinstatement of the Imperial system: http://en.wikipedia.org/wiki/Metrication_in_Canada#Reinstatement_of_the_Imperial_system 173.183.73.128 (talk) 06:26, 15 January 2011 (UTC)

Fahrenheit in the UK

Recently added by an anonymous contributor:

In the United Kingdom, Fahrenheit is used mainly during summer months, and Celcius during winter months.

Is this really true? If so, it's fascinating, and there's probably more to say about it. If not, maybe some kind Brit can remove it. Cdc 18:31, 30 Jan 2005 (UTC)

Yes, it's true.your dumb I live in Scotland and people refer to cold temperatures in Celcius and warm temperatures in Fahrenheit. I have trouble relating to temperatures like 39 ºF or 27 ºC, but I know what 4 ºC and 80 ºF feel like. I suppose we think in a scale of comfort where 0 is too cold, and 100 is too hot.

This is an anecdotal generalisation. 94.193.240.11 (talk) 14:23, 11 January 2011 (UTC)

Added by David Brinicombe:

Nobody has mentioned the BBC weather forecasts which have had to mediate between Celsius and Fahrenheit. There is certainly a resistance to metrication in previous generations, but schools have been teaching in metric for about two decades at least. The Meteorological Office, which supplies the UK weather forecast data, has been metricated like all scientific institutions since the War, but Britain officially adopted the Metric system universally in 1980.

Met Office forecasts at that stage gave Celsius temperatures in addition to Fahrenheit but some time in the 1980's (please check) decided to issue Celsius first and Fahrenheit second. The BBC weather forecasts followed this practice. The metric scale was still often called "Centigrade", but on official metrication, this was normally corrected. Wikipedia doesnl't seem to have a date for the introductio of "Celsius".

Current practice seems to be to give forecsats in Celsius and occasionally give a Fahrenheig equivalnet in parenthesis or as an observation.

One profession which has not gone over te Celsius is Medicine, where body temperture is still usually given in Fahrenheit. The British reluctance to change has resulted in a confusing situation.

Feb 2007 David Brinicombe 85.210.147.147 14:40, 22 February 2007 (UTC)

As this point seems to have become obscured in recent updates, I've just rearranged the last paragraph of the history section a bit to make note of Fahrenheit's continued use in parts of Great Britain. I also borrowed some phrasing from the metrication article, which mentions Canada as another partial holdout, and also included a phrase from the U.S. customary units article, which provides further explanation for the continued popularity of non-metric measurement, aside from the "temperate climate air temps range from 0–100 ºF" explanation already given. — mjb 07:12, 4 May 2005 (UTC)

Speaking as a Brit' I think this is sort of a half truth. Metrication was only made absolute standard in the last generation, subsequently younger people will refer to temperatures in Celcius - almost always, without fail - while older people use almost solely fahrenheit. Susbequently if you tried discussing temperatures with a mixed group of British you'd get the impression they use both. I havn't met many people how are well versed enough in both gauges to use them in that way, most are only adept at one gauge (Leading to much confusion) --80.242.32.51 00:18, 1 March 2006 (UTC) Ryuujin

I wouldn't agree that individuals don't mix the two systems. It's common to hear the same person use Celsius for cold temperatures and Fahrenheit for hot ones. Nearly everyone refers to freezing weather as 0 degrees (Celsius) but come summer the same people will say 'it's 80 degrees' meaning Fahrenheit. Crazy I know but a typical British 'compromise' Vauxhall1964 (talk) 22:28, 29 September 2008 (UTC)

Newspapers in Britain certainly use Fahrenheit for hot (weather) temperatures and centigrade for cold. I think it's so they can say 'temperatures approach 100 degrees!' or 'temperatures drop below zero!' as needs be. However, young people who are still in school tend to not encounter Fahrenheit much, and old people tend to stick to Fahrenheit alone. In between, where most people are, is this muddle. 86.139.237.132 15:15, 4 January 2007 (UTC)

Hi, I am from the United States. Just would like to tell you Brits that converting from Fahrenheit to Celsius is C=5/9(F-32) and Celsius to Fahrenheit is F=9/5C+32. There are 0 Celsius is 32 Fahrenheit (Freezing point), 100 Celsius is 212 Fahrenheit (Boiling point), 37 Celsius is 98.6 Fahrenheit (Normal body temperature). I have an aunt who lives in the United Kingdom. She talked to me on facebook and gave me that it was only -1 Celsius (which is 31 Fahrenheit) —Preceding unsigned comment added by 24.100.3.169 (talk) 04:40, 9 May 2010 (UTC)

And your point is...? 94.193.240.11 (talk) 14:23, 11 January 2011 (UTC)

Hi it's me again from the United States! Also Britain needs to revert to the Imperial system and use Fahrenheit for all weather forecasts. Who needs 1.27 metres when you got 50 inches? —Preceding unsigned comment added by 24.100.3.169 (talk) 04:41, 9 May 2010 (UTC)

I agree! who needs 1 metre when you got 39.3700787 inches? 139.143.5.160 (talk) 16:05, 28 July 2010 (UTC)

The UK will never abandon the our limited progress to metrication. The Daily Telegraph, perhaps the UK's most conservative newspaper, was one of the last papers to publish weather maps marked in Fahrenheit. However their website maps now show only Celsius. On the subject of metrication in general the Telegraph have been traditionally hostile. Sometimes this deeply-held and sincere passion resulted in hilarity. I remember reading an article about the Citroen 2CV whose original design specification was to transport 4 people and 50kg of farm produce to market at a speed of 60 km/h with a fuel consumption not exceeding 3 litres per 100 km. The "Torygraph", not normally a paper to dumb things down, "translated" the above into imperial, making it absolutely meaningless.

On another matter anyone old enough to remember "The Troubles" will recall that the IRA's bombs were often some multiple of 11 lb. Most probably, the Army estimated the power of bombs in kilograms of TNT and the media dumbed the figures down (or up, because a 44 lb bomb sounds bigger than a 20kg one). 87.112.242.245 (talk) 20:41, 31 July 2010 (UTC)

Speaking as a member of the 'younger generation', basically Brits nowadays use Celsius exclusively except when it is very hot. This is simply because the highest temperatures we get in Britain are around 100F, so it a good yardstick in heatwaves. In all other cases 99% of people use Celsius, and all weather forecasts use Celsius. — Preceding unsigned comment added by 122.183.253.38 (talk) 07:29, 18 April 2012 (UTC)

"Bands"

I edited the section about the "user friendliness" of Fahrenheit and reported that as a supporter's opinion. It seems to me quite parochial that people think their system is the only "natural" one: people using Celsius will develop similar scales, with the added benefit of ice formation made immediately evident by the minus sign.--Orzetto 11:52, 2 August 2005 (UTC)

Certainly. I also noticed this when my country switched from the guilder to the euro; after a few days it's like a mental switch flips and the euro seems normal. Shinobu (talk) 12:33, 3 June 2008 (UTC)

Danzig, Gdansk

I don't see where anybody voting on some other article's talk page was ever given the authority to decide this issue for this page. Gene Nygaard 23:31, 10 October 2005 (UTC)

Then please read the voting page and the associated talk pages. Anyway, to me it looks like a reasonable guideline, but if you feel a need to protest and make your voice heard, you can do it here: Talk:Gdansk/Vote/discussion. Shinobu (talk) 12:29, 3 June 2008 (UTC)

Common usage

"However, despite official attempts to displace it, Fahrenheit remains in use for everyday, non-scientific temperature measurement by the general population of many English-speaking countries out of habit."

I think the sentence makes the assumption that America is the only english speaking country and because they still use fahrenheit the rest of the english speaking world does.

I find this statement to be misleading. I live in New Zealand and Fahrenheit is never used here. I dont think there would be many people in the population who have any idea what temperatures in Fahrenheit mean. ie. very few people would know at what temperature water froze in degrees fahrenheit.

Other than american tv shows and movies i never here any reference to temperatures measured in fahrenheit, so would believe that the opposite of the statement is true.

Im fairly certain this state of affairs is common with Australia.

Common usage II

removed - "However, despite official attempts to displace it, Fahrenheit remains in use for everyday, non-scientific temperature measurement by the general population of many English-speaking countries out of habit."

As above. This does not hold true for much of the UK, and any of Australia or New Zealand. Additionally, virtually all non-english speaking countries use celcius. While I agree no critism is necessary/wanted or warrented of those countries which retain Fahrenheit, it's misleading to state the above.

Space?

This page seems to insist on putting a space between the number and the degree sign—32 °F as opposed to 32°F. I think the latter is what I tend to see in textbooks, though. For example, Fundamentals of Heat and Mass Transfer by Incropera and DeWitt (copyright 2002) and Fundamentals of Physics by Halliday, Resnick, and Walker (copyright 1997) both use the tightly-set version. Is there a rason to do otherwise?―BenFrantzDale 09:13, 26 January 2006 (UTC)

Yes. For one thing, to consistently follow a rule of putting spaces between numbers and symbols for units of measure. Second, to clarify that the temperature degree sign is associated with and butts up to the letter and not the number, and is inseparable from that letter. In other words, no 48° without a letter, no 37° to 53°C, and no 18° F with a space between the degree sign and the letter, another fairly commonly seen form especially in older works. Furthermore, the modern rules clarify that prefixes can be added to degrees Celsius, such as 13 m°C,[1] even though such formulations will rarely be encountered in practice (in part because this will almost always be a temperature difference and you can use mK instead with the very same number), it makes for consistent and easily understandable rules.

Yes, the closed up version was often recommended in the past. Less so now. For example, the NIST Guide for the Use of the International System of Units (SI), NIST Special Publication 811 (1995) says in section 7.2:[2]

• This rule means that:

• (a) The symbol °C for the degree Celsius is preceded by a space when one expresses the values of Celsius temperatures.

It often takes textbooks a few years to catch up with the new rules. In the 1970s, there were still many physics textbooks using "new" or "nt" as the symbol for newtons, even though "N" had been clearly established as the only symbol back in 1960. Actually, I think there are some 21st century textbooks still doing that; I know that there are still some websites of college science classes doing so. Gene Nygaard 13:37, 31 January 2006 (UTC)

Seems I'm five years late for this discussion, but I came in here wondering the same thing. Very interesting! – Kerαunoςcopia^◁_galaxies 22:39, 18 April 2011 (UTC)

Page name

Discussion moved to Talk:Units of measurement because it affects several units of measurement. bobblewik

Help

I am in need of help. I need information of Gabrial Fahrenheit

PLEASE HELP!!!

Though it's probably of no use to you by now, see Gabriel Fahrenheit Richard001 00:58, 10 September 2006 (UTC)

Graph to show relationship

A graph that shows the linear relationship between fahrenheit and celsius would be quite useful at the top, as readers could instantly visualize and understand the relationship between the two scales as soon as they reach the article. I don't have much skill at imaging myself, but maybe someone could make (or find) a suitable graph for these two articles? Richard001 00:58, 10 September 2006 (UTC)

Really simple, any graphing calculator can do it....two straight lines, crossing at the left with F rising more steeply. --Dan (talk) 18:47, 20 February 2008 (UTC)

   What do you mean "crossing at the left"? The lines cross at -40 degrees. Ted. 203.161.131.164 (talk) 04:17, 21 September 2009 (UTC)

Seventh Version

I was reading the History section and ran across this:

"A seventh version insists that Fahrenheit established the 100 °F point based on the temperature at which butter melts."

It was a good laugh, but unless someone provides a credible source, it should probably be removed. Bwhack 13:15, 13 September 2006 (UTC)

Formula wrong

I try to convert C into F using the formula "(C+32) * 1.8" (It's the formula on top of the page right.) However, it seems what you need to do is:

C * 1.8 + 32

Ex:

( 37 + 32 ) * 1.8 = 124F

37 * 1.8 + 32 = 98.6F

I didn't check on the other formulas, they may be wrong too. Correct me if I'm wrong though.

203.218.160.79 01:46, 25 September 2006 (UTC)

(Another user, on 11:08 HST 27 November 2006): The formula still appears to be wrong. Could someone fix this? I'm getting pretty absurd values out of it, but I don't trust myself to fix it.

All of the formulae are now correct. Michaelbusch 21:19, 27 November 2006 (UTC)

Estimating conversion from Celsius

If you are an American travelling abroad and want to understand the local weather reports in Fahrenheit, you can just double the Celsius temperature and add 30. This is easier than multiplying by 1.8 and adding 32 mentally. This formula gives an exact conversion if the temprature is 10°C (=50°F), and the further you go from 10°C, the less precise the estimate becomes. It probably should not be used for the melting temperature of iron or anything like that, but it's fine for outdoor temperatures. I derived this idea myself, so I guess it's original research. --Zachm 23:01, 10 October 2006 (UTC)

I think this approximate conversion is "common knowledge" as I've been aware of it for many years. Another somewhat useful conversion is 61 °F is approximately 16 °C (i.e. reverse the digits).Mspearpoint 10:41, 3 July 2007 (UTC)

It should be common knowledge, because it trivially follows from the formulas given in the article, just by replacing 5/9 by 1/2 which makes calculation simpler and choosing an origin for the scale that lies roughly in the center of the temperature range that one is likely to encounter. Most of the time you won't get anything below -10 or above 30 and usually the temperature lies between 0 and 20. Shinobu (talk) 12:12, 3 June 2008 (UTC)

The 16°C=61°F is interesting but not too useful as a "conversion" and not perfectly accurate either. I've been aware of the doubling of Celsius and adding 30 for some time. It’s an old pilot’s trick and pilots have to do that a lot in the US. I think my extension of this might be original but I'm not positive. And, it's not really "original", but my approach might be somewhat unique. . If you get comfortable remembering that double it and add 30 approximation, you can easily make the conversion exact. Merely adjust your result toward 50°F by 10% of the difference between your result and °50F. It might sound difficult but it’s not. So for example, if your preliminary approximation is 40°F, you would adjust it to 41°F. Or, if your preliminary result were 90°F, adjust it to 86°F. The formula is [°F]= ([°C]*2+30) + (50-([°C] * 2 +30)) * .1 which looks awful but it’s a lot easier to do in your head than [°F] = [°C] × 9⁄5 + 32. If one does the mathematics it’s easy to prove that the formulas are equivalent, so that’s why I say it’s not all that original.. just unique and easier. . It’s not too bad for converting from °F to °C either. The first step in adjusting away from °50F by 10% leads to some slight inaccuracies but it’s real close. To be accurate you’d have to adjust it away from 50°F by 11.111...% That’s not as easy to do in your head. 138.32.32.166 (talk) 23:36, 18 March 2009 (UTC) Paul Crawford (not a registered user)

I used the "x 2 + 30" conversion extensively while in the US. Another useful approximation is that F = C * 2 at around 200 C, useful for converting recipes. The cross-over point for that is 160 °C. —Preceding unsigned comment added by 80.63.33.30 (talk) 12:08, 2 July 2009 (UTC)

This question was placed on the main page and is moved here

Someone tell me what 20°C represents?? and 30? and 22, 25, 37. 40???

If you're serious (which I doubt), try Google:

for example: 20°C http://www.google.com/search?hl=en&q=20+C+in+F

20 °C represents the temperature one fifth of the way from melting ice to boiling water. :-) It turns out to be a comfortable temperature to live in, so most houses have there thermostates set somewhere between 18 and 22. Shinobu (talk) 12:02, 3 June 2008 (UTC)

NPOVing

I've been attempting to NPOV this article, but a couple of people have reverted. See the comments I made at User talk:Michaelbusch. Also, User:Ckatz claimed my version was "Americancentric," but an article on Fahrenheit is going to disproportionately focus on the US, since that's the main country where this system is used. At any rate, the important thing is that NPOV is maintained and both sides are given a fair hearing. FahrenheitUser 04:47, 27 October 2006 (UTC)

The unsubstantiated claims are not NPOVing. CMacMillan 04:51, 27 October 2006 (UTC)

Which claim is not substantiated? If anything stated as fact has not been cited, then please mark it with a "needs citation" claim and I will find citations. Additionally, what's been reverted is changes I've made to the tone of the article to make it more NPOV. Like I said, "the article before I got there had an anti-Fahrenheit POV and tone. Phrases like "Fahrenheit supporters claim" should be avoided. When you say that someone "claims" something, the implication is that they're claiming something dubious. Words like assert are better and more neutral." FahrenheitUser 05:05, 27 October 2006 (UTC)

To avoid cyclic reverts, I have not yet removed the material, which would be for about the fifth time. However, I agree with Ckatz that the version is Americancentric. Saying that this article must be Americancentric is false: an article can be about the USA without having a USA POV - that is implied in the definition of NPOV. Also, I believe the additions to be without basis in fact, as I have stated before, and also misleading. I recommend removal. Michaelbusch 05:01, 27 October 2006 (UTC)

I have reverted it. The text is (in addition to the other concerns) poorly written, uncited, and not particularly relevant. Fahrenheituser, you've been trying to insert this material for a while now, going against the wishes of several other editors. Why? --Ckatz^chat_spy 05:06, 27 October 2006 (UTC)

There... now it says "assert". --Ckatz^chat_spy 05:10, 27 October 2006 (UTC)

usa

who other than usa actually uses farenheit

Jamaica and Belize Use it as well.

-Just passing by :)

If anyone cares... I've seen the Jamaica/fahrenheit claim a few times now, but I haven't found any support for it. I searched Jamaican government websites and only found celsius. My wife just asked a co-worker from Jamaica, and he confirmed that Jamaica uses Celsius. Saraalan 13:18, 20 September 2007 (UTC)

I just deleted reference in the article to Jamaica using Fahrenheit. I'm not sure where to put this note to make it clear, but Jamaica officially has converted to celsius and teaches celsius. http://www.metservice.gov.jm/ Perhaps I should put a note in the article that "It's commonly thought that Jamaica uses Fahrenheit, but ..."? Saraalan 04:18, 30 September 2007 (UTC)

Proposed Terminology Change

Editors, please vote on the following:

---

john tedwards---

It's an interval scale and needs to be listed as such

I oppose this because this terminology is very infrequently used and will likely confuse most users. In occurdance with policy, I have reverted the additions until this matter is resolved. Michaelbusch 04:44, 19 November 2006 (UTC)

Unit of Scale

I would like to have all verbage removed that references Fahrenheit is 5/9 of a degree Celsius. This is incorrect and does not hold true at -40°F == -40°C Brammp 22:22, 29 January 2007 (UTC)

My understanding (Michael B. or other editors, please let me know if this isn't quite right) is that the units follow that ratio; however, the scales don't start from a common point. They cross over at -40, which is probably where the confusion arises. --Ckatz^chat_spy 22:44, 29 January 2007 (UTC)

Yes, (°C + 40) * 9/5 - 40 = °F and (°F + 40) * 5/9 - 40 = °C. Notice that 40 * 9/5 = 32 and 40 * 5/9 - 40 = -32 * 5/9. So the two units scale linearly in each other, it's just that the origin from which to scale isn't located at zero. Shinobu (talk) 11:53, 3 June 2008 (UTC)

Usage (Temperature bands)

Description of the 10deg bands are massively subjective. I can wear shorts and a T-shirt when it's in the 40s. I personally don't think breaking out every 10 degrees is necessary beyond mentioning it in what is now the lead-up. Maybe add mention that contour weather maps use 10deg increments. Marimvibe 00:28, 30 January 2007 (UTC)

I was just about to chime in with that. 0F is most certainly not "Extremely cold"; -40F, now /that's/ extremely cold. phrawzty 17:43, 4 February 2007 (UTC)

Site Correction

Hi,

Apparently someone rewrote part of the this page to stay childish things. Will someone fix it?

Thanks. —The preceding unsigned comment was added by 134.10.24.197 (talk) 08:10, 19 February 2007 (UTC).

Linkage of Farenheit scale to body temperatures

It is no suprise that there may be some ambiguity about which body temperature Farenheit may (or may not) have used. Resting healthy human temperatures vary with site of measurement, time of day, and activity. Axillary temperatures are about 1 C below rectal, and 0.5 C below sublingual. The normal quoted central range is 36.8-37.8 C. This falls with age. Otherwise healthy elderly people may have temperatures as low as 35.5. In short, there is nothing in the Farenheit scale which imports on whether he measured horses, cows, or humans, on whether he was well or sick or had just been out jogging when he stuck a thermometer in his mouth/armpit/ear or ......

Also, and suggestion that 1 F is the limit of sensitivity of a person is wrong. At around body temperature people are very sensitive to temperature changes, and further out less so. The capacity to sense a tempurature difference in a solid material depends strongly on the temperature of surrounding radiant surfaces (eg the walls of the room you are in: Under normal indoor conditions, with ambient temperatures ~20-25 C most heat transfer to an exposed human body is by radiation from solid bodies). I suggest that the article would be less confusing if the unknowable questions regarding what Farenheit (the man) may or may not have been thinking or measuring at the ~96-100 range were de-emphasised.

Of course, if there is some historical evidence that Farenheit actually measured horse blood, or tried to judge how small a temperature difference he himself could notice, that is historically interesting. Speculation in this doesn't add much though. BruceGramm 10:13, 4 March 2007 (UTC)

I was taught in school that the 100F point was defined as the temperature of Farenheit's pet dog. This is both reasonable and humourous, although of uncertain truth. 192.91.191.29 (talk) 08:32, 20 June 2008 (UTC)

100F is the temperature of a healthy horse's ass. Not kidding! Perhaps this was the true meaning of that miestone in Fahrenheit scale. It would have been very pragmatic in his time. — Preceding unsigned comment added by Jmcangas (talk • contribs) 02:06, 9 December 2011 (UTC)

Proposed WikiProject

Right now the content related to the various articles relating to measurement seems to be rather indifferently handled. This is not good, because at least 45 or so are of a great deal of importance to Wikipedia, and are even regarded as Vital articles. On that basis, I am proposing a new project at Wikipedia:WikiProject Council/Proposals#Measurement to work with these articles, and the others that relate to the concepts of measurement. Any and all input in the proposed project, including indications of willingness to contribute to its work, would be greatly appreciated. Thank you for your attention. John Carter 21:11, 2 May 2007 (UTC)

Exactness of definitions

This article is very imprecise when it comes to the definition of Fahrenheit. "Some time after his death, it was decided to recalibrate the scale with 32 °F and 212 °F as the exact melting and boiling points of plain water." - surely there must be a more precise definition than that: at what altitude? What barometric pressure? What does it mean by plain water? Is this an international standard? Is the scale now defined in relation to SI units (as some other imperial measurements now are)? And does anybody know who did this or when?

Also in the first section, it should make it clear whether absolute zero is exactly or approximately −459.67 F (or -459.67 to 2 decimal places, if you prefer to express it that way), in view of the fact that Celsius is defined by absolute zero being exactly 273.15 degrees below 0 C. If absolute zero in Fahrenheit is not an exact fraction, the article should clearly distinguish definitions from approximations. Unbendingtree 21:00, 11 September 2007 (UTC)

The statement "The zero point is determined by placing the thermometer in a mixture of ice, water, and ammonium chloride, a salt. This is a type of frigorific mixture. The mixture automatically stabilizes its temperature at 0 °F. " seems to be redundant to me. If not completely meaningless -- zero point was based on a mixture, which just happens to have a temperature of zero degrees fahrenheit? PirateAngel (talk) 19:54, 5 December 2008 (UTC)

Another exactness problem: The diagram showing the Fahrenheit scale in comparison the Celsius scale is incorrectly labelled centigrade (which has been obsolete since 1948). — Preceding unsigned comment added by 24.6.88.253 (talk) 03:52, 27 November 2011 (UTC)

Graffiti

Yea, some retard put Tara Rules there, and another "hi how r u doing i'm fine thanx". I think that we should cancel the editing if this happens again. I'll remove those two things right now. Ceil-Sama 10:04, 19 September 2007 (UTC)

The page history has an undo option now. It generally works quite well, and even when it doesn't the history can help you pinpoint the exact areas of text that are affected. Shinobu (talk) 11:38, 3 June 2008 (UTC)

Usage

I just deleted reference in the article to Jamaica using Fahrenheit. The statement referenced a tourism website aimed at U.S. travelers, so it proved nothing. I'm not sure where to put this note to make it clear, so I apologize for entering it twice. But Jamaica officially has converted to celsius and teaches celsius. http://www.metservice.gov.jm/ In addition to that link, I have found others supporting that point, and my wife has discussed this with someone from Jamaica. It's possible that there are people in Jamaica still using Fahrenheit, and statements to that effect are fine, but the idea that "Jamaica uses Fahrenheit" is not true. Should I put a note in the article that "It's commonly thought that Jamaica uses Fahrenheit, but ..."? Saraalan 04:17, 30 September 2007 (UTC)

Not unless it's notable and verifiable that it's commonly thought that Jamaica uses Fahrenheit. Anyway, thanks for the fix. Shinobu (talk) 11:36, 3 June 2008 (UTC)

Difficult to spell

http://www.celsius-to-fahrenheit.com/ has a list of misspellings of Fahrenheit that is quite impressive: farenheit, faernheight, fahenheit, fahernheight, fahranheit, fahreheight, fahreheit, fahrehnheit, fahreinheigt, fahreinheit, fahren, fahren heat, fahrenaites, fahreneheit, fahreneit, fahrengheit, fahrenghieght, fahrenhait, fahrenheid, fahrenheiet, fahrenheight, fahrenheite, fahrenheith, fahrenhet, fahrenhiet, fahrenhight, fahrenhite, fahriet, faireheit, fairenheit, fairenheite, fairenthigh, fairheight, fanrenhite, farahein, faranheat, faranhiet, faranhight, fareheint, fareheit, farehnait, fareienheit, fareigheight, fareighheight, fareignheit, fareingheit, fareinheight, fareinheigt, fareinheit, farengheit, farenhaid, farenhaight, farenhait, farenhaith, farenheat, farenheeight, farenheid, farenheidt, farenheight, farenheigt, farenheiht, farenheit, farenheite, farenheith, farenhieght, farenhiet, farenhight, farenhit, farenhute, farenight, farheight, farheneight, farheneit, farhenheit, farhenhiet, farhenit, farhienhiet, farhreheit, farhrenheit, fariegn, farienheight, farienheit, farienhieght, farienhiet, faringhight, farinhaert, farinhart, farinheight, farinhight, farinhit, farneheit, farnehight, farneit, farnheit, farnhiet, farren height, farrenheit, fehernheit, fehrenheit, fehrenhit, fehrenhite, feirenheirt, feirinheight, fenrnhight, fereheith, fereinheit, ferenheight, ferenheit, ferenheith, ferenhight, ferenhite, ferheinight, ferhienight, ferienhiet, ferihite, ferinheight, ferinheit, ferinhet, ferinhiet, ferinhight, ferinhite, fernheit, fernhit, fharenheit, foreignheit, forenghiet, forenhiet, franenheit, and frenihieght

A search for almost any of these misspellings comes up with no result. Is there any way to include this in the page in some kind of meta-info so that these misspellings of fahrenheit bring it up when people search for it? Or should we just use 80 redirect pages?Brinerustle 08:21, 1 October 2007 (UTC)

Usually we don't link from misspellings because the base for which misspellings to include and which not to include is completely arbitrary. However, sometimes a misspelling is so common that we link it for convenience, in which case the {{R from misspelling}} template can be used to signify this. That said, I don't think Fahrenheit is particularly hard to spell and I think most of the misspellings you listed look contrived and I cannot imagine that any of them are even remotely common. Shinobu (talk) 11:34, 3 June 2008 (UTC)

Usage Citation?

I find it interesting that someone feels it necessary to provide a published, verifable source for the statement that "Fahrenheit is still sometimes used by older generations in many English speaking countries, especially for measurement of higher temperatures and for cooking", whereas similar statements are made in the Celsius#Worldwide_adoption section without any such requirement. However, if the WikiMasses insist, I'll start throwing up ISBNs of cookbooks in current publication. 142.162.37.141 (talk) 04:21, 28 October 2008 (UTC)

Dangit; tried to 'watch this page' and found I wasn't signed in - the above is me *blush* Empath (talk) 04:25, 28 October 2008 (UTC)

big deal?

Temperatures and intervals

As with the Celsius scale, the same symbol, "°", is used to denote both a point on the temperature scale, with a letter (C, F) indicating which scale is being used (e.g. "Gallium melts at 85.5763 °F") and to denote a difference between temperatures or an uncertainty of temperature (e.g. "The output of the heat exchanger is hotter by 72 °C," and "Our standard uncertainty is ±5.4 °C").

... that's a characteristic of each and every "interval/cardinal scale". Just think of measures of distance, volume, weight, etc. Is there any reason to leave that information in the article? --Ibn Battuta (talk) 10:08, 30 November 2008 (UTC)

"the words are too complicated, i'm just a kid after all." —Preceding unsigned comment added by 68.37.230.187 (talk) 00:46, 10 January 2009 (UTC)

Ammonium or Sodium?

The References 2 and 3 and the article Frigorific mixture state the use of common salt i.e. sodium chloride (NaCl) as a part of zero reference. The article makes use of reference 6 which states ammonium chloride (NH4Cl). Can someone competent correct this? —Preceding unsigned comment added by 212.222.53.82 (talk) 14:46, 9 January 2009 (UTC)

more on history

i think i read once that Fahrenheit designed the scale so that 0 and 100 would be the lowest and highest temperatures likely to be encountered where he lived (Germany) and then later more precised it —Preceding unsigned comment added by 170.170.59.138 (talk) 20:46, 28 February 2010 (UTC)

The original scale Fahrenheit based his scale on was set so 0 was colder than it ever got in Denmark: Straight Dope on Fahrenheit].162.40.51.251 (talk) 02:33, 4 March 2010 (UTC)

Article contradicts itself with regard to representation

In the "Definition and conversions" section:

In science there are no degrees in the Fahrenheit scale and degrees only exist in the Celsius scale. Example, 32F (not 32°F) is 0°C.

In the "Representation" section:

The Fahrenheit symbol has its own Unicode character: "℉" (U+2109). This is a compatibility character encoded for roundtrip compatibility with legacy CJK encodings (which included it to conform to layout in square ideographic character cells) and vertical layout. Use of compatibility characters is discouraged by the Unicode Consortium. The ordinary degree sign (U+00B0) followed by the Latin letter F ("°F") is thus the preferred way of recording the symbol for degree Fahrenheit.

So which is it? It can't be both with and without the degree sign. HumphreyW (talk) 13:21, 20 September 2010 (UTC)

Three points?

"According to an article Fahrenheit wrote in 1724,[4] he based his scale on three reference points of temperature

• The zero point is determined by placing the thermometer in brine: he used a mixture of ice, water, and ammonium chloride, a salt. This is a frigorific mixture which automatically stabilizes its temperature at 0 °F.
• A mixture of ice and water also stabilizes, either freezing or melting at 32 °F,[5] though Fahrenheit did not use this point in defining his temperature scale.
• The third (???) point, 96 degrees, was the level of the liquid in the thermometer when held in the mouth or under the armpit of his wife."

If Fahrenheit didn't use the water and ice reference point, then I can see only two points here. Lampak (talk) 17:21, 1 October 2010 (UTC)

Because there are only two points, 0 [freezing brine] and 100 [human body temperature prior to revision]. Some edit in the past made a nonsense of the text in multiple ways. I have corrected it using the citation from Physics for future Presidents which explains it all clearly. --Red King (talk) 23:07, 3 October 2010 (UTC)

Revised Awkward Usage section

OK, it seems somebody created, and somebody else deleted sections called Advantages/Disadvantages. This is ridiculous. Of course such a section can exist. You just add citation needed links to the places where citations are needed.

"Various reasons are given for the resistance to the Celsius system in the U.S., including the larger size of each degree Celsius (resulting in the need for decimals where integer Fahrenheit degrees were adequate for much technical work). For example, 68 °F, 69 °F, and 70 °F correspond to 20 °C, 20.6 °C, and 21.1 °C, respectively. Another reason is the lower zero point in the Fahrenheit system which reduces the number of negative signs when measurements such as weather data were averaged.[10] On the other hand, most countries which formerly used the Fahrenheit system, such as New Zealand and Australia, have totally switched to the Celsius system.[11]"

belongs in the article, but does not belong under Usage. I will leave it in Usage for the time-being.

Also, rather than listening haphazardly countries that don't use Fahrenheit, it would be more concise to word it such: "Many countries that priorly used the Fahrenheit scale no longer do, in favor of the Celsius scale. These countries include ..."

"Most other countries have adopted Celsius as the primary scale in all use." is entirely irrelevant. These countries might not use Celsius, but this is not an article about Celsius. A list of countries that formerly used Fahrenheit is sufficient.

I have reworded these things, and generally made things more professional and concise. -Afisamule'al 04:17, 10 October 2010 (UTC)

Edit: I have also revised other parts of the article. Remember, this article is about Fahrenheit, and not about Celsius. In General, Fahrenheit should be mentioned first, and Celsius perhaps not mentioned at all. —Preceding unsigned comment added by Titan485 (talk • contribs) 04:28, 10 October 2010 (UTC)

American cookbooks in Canada problematic?

The article implies that Canadians have issues with American cookbooks because Americans use the Fahrenheit scale whereas Canadians tend to favour the Celsius scale. This is laughable and untrue. Virtually ALL ovens in Canada employ the Fahrenheit scale and Imperial measures continue to dominate in Canadian kitchens (teaspoons, tablespoons, ounces, cups, etc). In fact, the Imperial system is still legal in Canada and may be used wherever and whenever so long as a metric equivalent is given (though this isn't always enforced meaning some grocers show prices ONLY in Imperial units). Canada is unique in that BOTH systems are perfectly legal and acceptable: http://laws.justice.gc.ca/eng/W-6/page-2.html#anchorbo-ga:s_4 173.183.73.128 (talk) 06:22, 15 January 2011 (UTC)

32° Fahrenheit is not the freezing point of water

I am a meteorologist. I mention this because I'm going to have a tough time coming up with proper documentation at this moment except to say this is what I learned in class:

32° Fahrenheit is not the freezing temperature of water. It is the melting temperature for ice.

There are many conditions in which pure water remains liquid at temperatures below 32° Fahrenheit. It is commonly found as "super cooled water" in clouds. However, ice never exists when its temperature is above 32° Fahrenheit. This is a small distinction, but a distinction with a difference nonetheless.

I have refrained from changing the entry, because I'd like some feedback and to make sure I haven't missed something.

Geofffox (talk) 15:36, 23 January 2011 (UTC) Geoff Fox

That is a good call and I will change the article accordingly. The Celsius scale is even more precise: it defines 0°C as the triple point of H₂O, so that the problem you describe can't arise. --Red King (talk) 12:09, 25 January 2011 (UTC)

"Fahrenehit is a secondary scale in the UK".

I believe that this is false. Fahrenheit has no status whatever in the UK. Yes, there may be a few people who still use it, like they think in £sd, but that is not the same as an official secondary scale. Yes, the shops sell dual-scale thermometers, but they are made in China primarily for the North American market, but again, that is not evidence of any status. --Red King (talk) 12:29, 25 January 2011 (UTC)

Disagree- Ovens are all in fahrenheit unless their european models. Also newpapers still regularly quote temperatures (especially in summer) in fahrenheit --88.104.33.187 (talk) 22:14, 2 February 2011 (UTC)

I haven't seen an oven calibrated in Fahrenheit for sale on the UK market in at least 20 years. Also, it only the tabloids that go for the 'temperatures in the nineties' headlines (more impressive than 'in the thirties') – and then use Celsius in winter because -20 [C] is more impressive than -4 [F]. People watch american TV programs, they can handle it.--Red King (talk) 20:12, 20 February 2011 (UTC)

Despite years of weather reports using Celsius, in my experience the majority of older people in the UK still always think of weather temperatures in Fahrenheit.81.159.76.94 (talk) 13:30, 5 February 2011 (UTC)

Then, as Red King says, it is not an official scale. Xionbox (talk) 22:30, 20 February 2011 (UTC)

Cayman Islands

The Caymans still use the Fahrenheit scale:

http://www.cayman27.com.ky/news/weather

Added to the article. Xionbox^₪ 08:11, 10 March 2011 (UTC)

Degrees Fahrenheit???

I was always explicitly taught that there were no degrees in the Fahrenheit scale. The reference I will try and dig up in one of my old OU Degree science books. I discussed with a few of my colleagues and they all agree that the British classical taught sciences never had degree Fahrenheit, only the number followed by the F. Can anyone else confirm this whilst I look up my references? —Preceding unsigned comment added by 96.224.225.45 (talk) 20:49, 30 April 2011 (UTC)

The only scale not using degrees is Kelvin. I think you got confused because people tend to drop the "degree" in spoken language. 87.188.214.132 (talk) 13:14, 26 May 2011 (UTC)

Canada

"In Canada, Celsius is the sole official system[6] and is used in the news, weather forecasts, books, magazines and daily conversations. But, due to habit (especially in older generations, since Canada officially abandoned Fahrenheit for Celsius the first of April 1975) and because of close relationships with the United States (tourism, etc), personal outdoor and indoor thermometers, including both digital and analogue, may display temperatures in Celsius, Fahrenheit (if old or bought in the United States), or both."

---

I am revising this. Technically speaking, the "Celsius scale" has absolutely no legal status in Canada anymore than the "Fahrenheit scale." The Celsius scale is a component of the International System (Metric) just as the Fahrenheit scale is a component of the Imperial/Canadian/US Customary system. The International System is preferred by the Canadian government and thus usually takes precedence to the Imperial/Canadian system. That being said, it is factually incorrect to say "In Canada, Celsius is the sole official system." One, the Celsius scale is not a "system" in and of itself (but rather a component of a system -- as mentioned prior) and, two, as much as some frustratingly continue to argue or believe otherwise -- the Imperial/Canadian system of measurement is STILL legal and used in Canada. I don't know why we have to keep going over this ( http://laws-lois.justice.gc.ca/eng/acts/W-6/page-19.html#h-17 ). Due to Canada's unique reality, Environment Canada still has an Imperial/Fahrenheit option on its website ( http://www.weatheroffice.gc.ca/forecast/city_e.html?bc-74&unit=i ). This is in complete contrast to fully metricated countries like Australia and New Zealand (whose weather bureaus DO NOT offer an Imperial/Fahrenheit option).

---

"But, due to habit (especially in older generations, since Canada officially abandoned Fahrenheit for Celsius the first of April 1975) and because of close relationships with the United States (tourism, etc), personal outdoor and indoor thermometers, including both digital and analogue, may display temperatures in Celsius, Fahrenheit (if old or bought in the United States), or both."

---

This is hearsay at its finest and really attempts to "ram down the reader's throat" that Fahrenheit is NOT used in Canada and has been "abandoned." Absolutely ALL cooking ovens in Canada employ the Fahrenheit scale (as Imperial/Canadian measures still DOMINATE Canadian recipes), and some (even among my group of 26 year old friends -- certainly NOT of the "older generations") continue to give their body temperatures in Fahrenheit as well. Regardless of Canada's close relationship to the United States, the Fahrenheit scale is still technically legal for use within Canada (as per Imperial's legality). End point. Therefore, to say the Fahrenheit scale is used solely because of Canada's close relationship with the United States is pure speculation. Legally, one absolutely cannot speculate as to why Canadian thermometers are dual listed without ALSO taking into account the simplistic notion of Fahrenheit's continued legality in Canada. Also, the implication that thermometers displaying Fahrenheit in Canada are always bought in the United States is flat out incorrect. Virtually every single thermometer sold in Canada is listed in Fahrenheit as well as Celsius. This is in full compliance with Canadian law ( http://www.canadiantire.ca/AST/browse/2/OutdoorLiving/GardenDecor/ClocksThermometers/PRD~0429116P/12-in.%252BThermometer%25252C%252BWhite.jsp?locale=en, http://www.canadiantire.ca/AST/browse/2/OutdoorLiving/GardenDecor/ClocksThermometers/PRD~0429115P/Outdoor%252BThermometer.jsp?locale=en, http://www.canadiantire.ca/AST/browse/3/HouseHome/HomeDecor/Thermometers/PRD~0429929P/Deluxe%252BWeather%252BStation.jsp?locale=en ). 173.180.193.139 (talk) 08:29, 5 June 2011 (UTC)

Yes I completely agree with what's been said: the truth is that Fahrenheit is still seen in Canada, and legally is able to be used as long as metric equivalents are also displayed. However, since that's a secondary scale I'm going to see if there's a way to set up a separate section since writing that "Canada uses it as a secondary" etc gives it undue weight; the point is which countries use it as their main system for the header, and then perhaps a more thorough approach throughout the article.

--74.14.48.171 (talk) 23:13, 1 October 2011 (UTC)

Sincerest Apologies; not aware I was not logged in. --Cpt ricard (talk) 23:15, 1 October 2011 (UTC)

Thailand

There was a reference to Thailand using Fahrenheit in the first paragraph. However, the evidence suggests that Celsius is what is used. See: the Thai Meteorological Department and the the tourist weather forecast. I have therefore removed the reference to Thailand. Michael Glass (talk) 15:40, 12 June 2011 (UTC)

Usage ([dis]advantages)

It seems that some people here violently hate any mentioning of Celsius scale advantages. :-)

When I tried to add a brief reasoning why most people have switched to Celsius, one user removed it immediately as "Undo WP:POV and WP:OR" instead of tagging it with appropriate templates (in fact, returning the paragraph to its unbalanced POV). Then I found and added a supporting reference, and it survived for a while, until another user with a very amusing edit history deleted everything, including the reference, without any comments whatsoever...

I'm not putting it back right now, since the structure has somewhat changed, but would like to discuss the Fahrenheit/Celsius issue here. (Here was the original reasoning.)

As related to weather, it really makes more sense to have 0 °C at the water melting point: for "positive" temperatures you expect rain and puddles, for "negative" — snow and ice, and for temperatures near "zero" the weather is bad and dangerous (slush, road icing).

The "100 degrees" point is not that important here. The fact that 100 °F is close to the normal human body temperature is also of little importance, since different people (and in different psycho-physical conditions) have quite different comfort temperature ranges, generally lying below 100 °F anyway.

Other factors, such as wind and humidity have a substantial effect on the "apparent temperature" as well (see tables).

This also makes "1 °F is more accurate than 1 °C" claims irrelevant for current temperatures. As for forecasts, they actually have accuracy not better than 2 °C (3 °F) even for the next day (see here, also here). Another interesting thing to notice is that the forecast worded as "low seventies" (customary for Fahrenheit scale) has the same accuracy as the statement "same as today". ;-)

The reasons against the Celsius scale current given in the article are also questionable:

1. While switching from °F to °C might require more decimals is some cases, it might as well reduce the numbers, say, from 3 digits to 2 digits (or from 4 to 3) in other cases. Since there is no estimation of the relative frequency of these two possibilities, it doesn't tell which scale is "better". (In fact, returning to weather, any temperature requires at most 2 digits in Celsius, but often requires 3 digits in Fahrenheit.)

2. The mentioned "number of negative signs" argument was probably this: "The worst difficulty, however, is in the use of the centigrade scale below freezing. Any one who has had to study figures half of which have minus signs before them knows the amount of labor involved. To average a column of 30 figures half of which are minus takes nearly double time that figures all on one side would take, and the liability to error is more than twice as great." (taken from the cited reference, p. 165). It sounds quite ridiculous not only because nowadays nobody has to do these calculations mentally, but also because even in the old times there were tricks to sum "figures half of which are minus" efficiently (for example; and keep in mind that in a list of temperatures the "minuses" would be not randomly scattered, but pretty much grouped, so the addition takes just a little longer, not "nearly double time").

Would be interesting to collect more information on the question and write something better than what we have right now in the article.

Mikhail Ryazanov (talk) 07:54, 29 July 2011 (UTC)

Cayman Islands

The article implies that the Caymans only use the Fahrenheit scale because the islands receive large numbers of US visitors. The Cayman Islands uses the British imperial system (all distances are in miles, speeds in mph, fuel is sold by the "imperial gallon", etc). Fahrenheit is to the imperial system as Celsius is to the metric. Therefore, the notion that the Fahrenheit scale is used solely to accommodate US visitors is hearsay (considering the Caymans use the imperial system). The article should be amended accordingly. 173.180.193.139 (talk) 12:07, 14 August 2011 (UTC)

Yes, the suggestion that it does so for US visitors should be removed. However the fact remains that the Cayman Islands Goverment meteorological service gives reports in celsius first and fahrenheit second. --Red King (talk) 16:24, 16 August 2011 (UTC)

And your point is? Again, the Caymans are not metric. 173.180.193.139 (talk) 23:32, 17 August 2011 (UTC)

Actually, you are incorrect. The Cayman Meteorological Service gives the temperature in Fahrenheit FIRST. http://www.weather.gov.ky/portal/page?_pageid=1142,1481932&_dad=portal&_schema=PORTAL 173.180.193.139 (talk) 23:35, 17 August 2011 (UTC)

How odd. I'm certain that it was the other way round when I looked. Is someone there reading Wikipedia? --Red King (talk) 14:30, 19 August 2011 (UTC)

RE:"...somewhat inaccurately, that water boils at about 212 degrees..."

From the statement: "Fahrenheit observed, somewhat inaccurately, that water boils at about 212 degrees using this scale". I changed it to: "Fahrenheit observed that water boils at about 212 degrees using this scale"

My reasoning is that while it is true that °F rather than 212.0 °F is the temperature that water boils at, the term "somewhat inaccurately" is vague and redundant as later in the sentence the the lack of precision is inferred by using the term "at about".

Also the Fahrenheit scale is used by laypeople as a rough general estimate of the temperature for practical applications such as when operating imprecise consumer equipment where the technical difference between 212.000 and 211.971 — Preceding unsigned comment added by 99.207.184.132 (talk) 12:58, 20 January 2012 (UTC)

Conversion calculations appear non-standard

While there are no definitive sources for how a conversion calculation should be represented, I personally find the chosen formula to be counter intuitive and non-standard (based on all other internet sources). Since all unit of measure conversions (including Fahrenheit) can be thought of as linear equations, it makes sense to display them in a standard linear equation form (i.e. 'y = Mx + B'). While the current format has the benefit of a good 'precision to brevity' ratio, the multipliers (slopes) are also factored into the offset (intercepts) leading to the appearance that the formula is incorrect.