Talk:Fahrenheit/Archive 2

99% of countries usa Celsius
I have reworded the sentence that contained the sentence "99% of countries". The "99%" is an over-estimate. If we countries in terms of UN memebership, the artcile cites four countries that use Fahrenheit, making 98% a more realistic number. If we work in terms of population, abput 5% of the world's population lives in the US. Moreover the sentence stated that this number of people changed to the Celsius scale durign the last part fo teh 20th century - not true - in many parts of the world, the Celsius scale was in use in the 19th century.-User:Martinvl (talk) 06:58, 27 February 2013

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 &deg;C at the water melting point: for "positive" temperatures you expect rain and puddles, for "negative" &mdash; 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 &deg;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 &deg;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 &deg;F is more accurate than 1 &deg;C" claims irrelevant for current temperatures. As for forecasts, they actually have accuracy not better than 2 &deg;C (3 &deg;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 &deg;F to &deg;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)
 * The objection to the minus symbol is as real today as ever. This is why negative numbers on balance sheets are often either in red ink (black is used for positive numbers), or are in brackets.  It is very easy to overlook minus symbols - this is especially true in an age of photocopiers and scanners.--Toddy1 (talk) 09:21, 19 May 2013 (UTC)

Removal of original synthesis
I have reverted the addition of what I believe to be original synthesis in the Usage section. The contributing editor appears to have drawn a conclusion about UK usage based on three samples of data that they selected from British newspapers. As the conclusion that the editor presented was not published in either of the three samples that were provided as supporting references, I believe that it contravenes both WP:SYN and WP:V. The references provide samples but do not support the added content. Dissimilar name (talk) 10:30, 4 July 2013 (UTC)
 * I have removed the whole of the United Kingdom paragraph as nothing is reliably sourced. If you can find reliable sources, then use them, but do not cherry-pick samples. Martinvl (talk) 11:34, 4 July 2013 (UTC)
 * You are confirming then that the edit summary in this change of yours was simply untrue. Dissimilar name (talk) 11:46, 4 July 2013 (UTC)
 * No I am not. I have decided to play this one by the letter - every phrase in that paragraph will be examined.
 * Cooking instructions on packaged food use dual temperature scales. The degree should be quantified using a reliable source. I checked the packaged food that we have in our freezer.  Most of it had dual temperature scales - degrees Celsius and Gas Mark.  There was no mention anywhere of Fahrenheit.  While the sentence might technically be correct, it is totally misleading.  I therefore propose that this phrase has no place in the article and unless it can be justified and clarified which two scales are used, that it be removed.
 * ... dual-unit thermometers are readily available. Again, please quantify this - do you have any citations that show the relative availability of Fahrenheit-only, dual unit and Celsius-only thermometers.  I have seen large numbers of Celsius-only thermometers in garden centres, so unless there is a reliable citation, this statement is misleading.  Again, I propose that it be removed from the article.
 * We will look at the media later.
 * Martinvl (talk) 11:50, 4 July 2013 (UTC)
 * By answering "No I am not", you imply that you think your edit summary was correct and true. Is that the case? Dissimilar name (talk) 12:04, 4 July 2013 (UTC)
 * Continuing with the analysis:
 * with newspaper and online weather reports quoting temperatures in both Celsius and Fahrenheit (or having an option to enable this), . Again a gross exaggeration of the truth.  There is a fundamental difference between "weather reports" and "weather stories": reports appear day-in and day-out in the same format, stories are one-off news items.  The citation that followed this phrase belonged to a weather story, not a weather report.  The citations that were removed showed quite clearly that the Daily Telegraph uses Celsius only and the Times has a Celsius-to-Fahrenheit converter.  This is hardly "quoting temperatures in both Celsius and Fahrenheit".  I propose removing that sentence unless the degree to which Celsius and Fahrenheit are used can be quantified.
 * Martinvl (talk) 12:15, 4 July 2013 (UTC)
 * However, that is only your personal opinion based on your personal observations of 3 specific newspaper weather reports. To comply with WP:V, you need to provide a reliable reference for that, one which explicitly reports and supports the conclusion that you synthesised. If such a source can be found, then by all means add that conclusion, but attributed to the person or organisation that makes it. That is how encyclopaedias work. Dissimilar name (talk) 12:25, 4 July 2013 (UTC)

Generally speaking, both Celsius and Fahrenheit are in continued use in the UK - I don't think (correct me if I'm wrong) that is disputed. The questions are whether we want to attempt to quantify how much each is used, and if so, how we can do that without resorting to personal opinion and OR. Dissimilar name (talk) 12:17, 4 July 2013 (UTC)
 * There is no way we can do this without using WP:OR. The only question is how much of the unsourced stuff is so factually wrong that it should be stripped out. Martinvl (talk) 12:26, 4 July 2013 (UTC)
 * Do you agree that both Celsius and Fahrenheit are in use in the UK? Dissimilar name (talk) 12:39, 4 July 2013 (UTC)

Celsius-Fahrenheit image
I read your comments at File talk:Thermometer CF.svg.

Firstly, "degrees Centigrade" were renamed "degrees Celsius" is 1948 - see "" and this Wikipedia text. The renaming was to resolve the issue as to whether the name "Centigrade" referred to a temperature (in English) or to an angle (the French angular measure was 100 grades = one right angle and 100 centigrades = 1 grade).

The image itself does not state that tghe two points in question actually define the respective scales, merely that for practical purposes, those are the observed temperatures. I have reinstated the image. Martinvl (talk) 06:57, 9 August 2013 (UTC)

How to use fahrenheit, I use celsius
Hi,I want to know how to use fahrenheit,please let me know how. — Preceding unsigned comment added by Alhadialbuhumud (talk • contribs) 22:24, 16 September 2013 (UTC)
 * Fahrenheit is a much simpler and more intuitive scale than Centigrade. With Fahrenheit, seawater freezes at 0, and freshwater freezes at 32, and freshwater boils at 212 degrees.  These are very easy simple numbers to remember - you see there are 180 degrees between the freezing point and boiling point of fresh water.  You will find that many English language publications use Fahrenheit, and also feet and inches, and sometimes make mistakes when converting these simple measures into confusing metric scales.  So it is best to know Fahrenheit and feet and inches.--Toddy1 (talk) 05:51, 17 September 2013 (UTC)
 * You know, sarcasm, irony, and cynism don't work very well in written communication. You should try to avoid it or at least mark it somehow, otherwise people could take your text for serious. --89.204.154.55 (talk) 12:02, 8 October 2013 (UTC)

100 degrees Fahrenheit
I remember being told at school that 100 degrees Fahrenheit was defined as the normal blood temperature of the ox! Can't find any evidence for that though, I guess my teacher was ill-informed? — Preceding unsigned comment added by 2A03:9600:1:2:DCB8:87BC:AB54:2EF3 (talk) 16:28, 7 January 2014 (UTC)

Zero degrees fahrenheit - inaccurate origin
Cecil Adams of the Chicago Sun-Tribune has just written his usual blunt debunking of a topic, in this case the old story that Fahrenheit originally chose the zero degree point on his scale because it was the the freezing point of sea water. I won't regurgitate his column here, but his point is very clear: Although zero degrees is something approximating the melting point of sea ice, that's not why he chose it. In fact, 0 degrees Fahrenheit was chosen by measuring the distance between "body heat" mark and the mark indicating the freezing point of fresh water, measuring half that distance below the lower mark, and calling that zero. That it happened to be about the freezing point of sea water - a value that varies depending on the salinity and purity of the sea water, making it largely useless for calibration - was a coincidence, one that he describes only so that the zero point of his scale doesn't seem to be flapping around untethered. In reality, his purpose was to choose a number low enough that it wouldn't be encountered in everyday measurement, avoiding the awkward use of negative numbers.

Although Cecil Adams is, in my opinion, about as close to god on such topics as we are likely to find on earth, I haven't updated the article yet, pending other people weighing with potentially opposite views. Ivan Denisovitch (talk) 15:57, 31 January 2014 (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.

--- any british commonwealth country (as in all of uk, new zealand, aus, several small pacific islands and large chunks of south africa) have all moved to metric only systems. america is one of a minority of countires who still use farenheit and imperial but studies show a distinct move off it. 203.219.85.18 (talk) 00:30, 7 June 2014 (UTC)

Second Paragraph - US Territories
The parenthetical exception in the second paragraph states that Puerto Rico predominantly uses Celsius. I believe this is mistaken, the temperature scale commonly used is Fahrenheit. It is the scale used for legislation, newspapers, as well as everyday use. — Preceding unsigned comment added by 24.227.8.126 (talk) 23:57, 15 July 2014 (UTC)

UK media use
"When publishing news stories, much of the UK press adopted a convention of using degrees Celsius in headlines relating to low temperatures and Fahrenheit for high temperatures."

Is this still the case? I've not noticed it, and our citation (a 2006 story) may be discussing previous rather than current practice. Andrew Gray (talk) 11:04, 30 December 2014 (UTC)
 * It depends what newspaper you read. The Independent, The Guardian, and The Mirror in stories in 2013-14 used Centigrade for "heatwave"s.  The Express and The Telegraph 2014 used Centigrade with Fahrenheit in brackets.  The Mail used Fahrenheit in the story I found, but the story was not dated.--  Toddy1 (talk) 11:23, 30 December 2014 (UTC)

how to
The article states: "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.[33]"

OK, so:===>>>  How do you actually type that and have degrees F show up. I type those letters and I get those letters. Not helpful. Useless information from people who know how to do things. Here you go:  U+2109. Typed it. I get what I typed. It would be useful and helpful if the article actually told people how to do it. Typing those keys gets you nowhere. Thanks. — Preceding unsigned comment added by 192.214.192.58 (talk) 17:52, 15 February 2015 (UTC)

Canada
Suggest the sentence "Canada retains it as a supplementary scale that can be used alongside Celsius" be removed from the introduction. The introduction deals with legally defined temperature scales in various places; in Canada the Weights and Measures act defines Kelvin as the standard, and Celsius as a supplementary unit. Nowhere does it mention Fahrenheit (altho it does define some non-metric units, including two "foot" measures of different length). I think the casual use of Fahrenheit in Canada is adequately described in the Usage section, and thus does not need to be in the introduction. — Preceding unsigned comment added by 2601:3:4480:6E0:3C97:5B9B:18D5:F65F (talk) 13:10, 25 May 2015 (UTC)


 * I would agree, the references provided that link to the Weights and Measures Act do not list Fahrenheit. Further investigation of the entire Act shows that Fahrenheit is not defined or mentioned.  As the section seems to be reporting about the official use of Fahrenheit, the line in question does not fit with the theme of the paragraph. Simcoe (talk) 18:50, 28 May 2015 (UTC)


 * The problem with this line of thinking is that the United States does not declare Fahrenheit official either, so we cannot assume the opening section speaks only to regions that make official use of Fahrenheit. The National Institute of Standards and Technology (NIST) lists Kelvin, Celsius, and Fahrenheit as well as the convertibility equations among all three scales, but nowhere does NIST say Fahrenheit is official: http://www.nist.gov/pml/wmd/metric/temp.cfm Fahrenheit's use and status, like Celsius's, is nuanced and warrants critical thought. When Canadian imperial units were the sole measurement system in Canada, even then a comparative definition for Fahrenheit was not listed in any Department of Justice or Industry Canada publication. The reason for this is because the Fahrenheit scale is unofficially considered part of the imperial system (for which Canada, unlike other fully metricated countries, still maintains legal definitions that permit its contemporary use), just as Celsius is unofficially considered part of the metric system: http://laws-lois.justice.gc.ca/eng/acts/w-6/page-20.html#h-30 Therefore, saying Canada retains Fahrenheit as a supplementary scale—supported by official federal TSB publications, the ages of which are irrelevant provided they were published after April 1, 1975—that can be used alongside the more common Celsius is accurate and gives the reader a sense of Fahrenheit's legal permissibility. It is true many Canadians casually use imperial units, but such usage is allowed legally.


 * Canada will never be 100% metric until the government completely outlaws the use of imperial units (as Australia, New Zealand, and South Africa have done), Canadians start referring to their height and weight in metres and kilos, metric equivalents of 2x4s are sold, ovens are set using Celsius, recipes call for grams instead of ounces, and Canadian railways start measuring distances and speeds in kilometres and km/h. To imply or give the impression that Canada is 100% metric—like France and Germany—is simply incorrect and runs contrary to the principles of being encyclopedic. NorthernFactoid (talk) 04:51, 22 July 2015 (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, 03:55, 7 March 2003 (UTC)


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

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. — Preceding unsigned comment added by MidgleyDJ (talk • contribs) 22:45, 3 December 2005


 * It is becoming less common, but in the UK it is still common to think of summer temperatures in terms of 70s - comfortable, shirtsleeves; 80s - 'proper summer weather'; 90s - Scorchio! Stub Mandrel (talk) 10:47, 22 July 2016 (UTC)

Undone contribuion
I added: "The Fahrenheit scale is a little impractical insofar because one degree Fahrenheit is on the small side for day to day applications. Henece US weather forcasts typically use designations like "upper sixties", which is effectively a 5 degree range."

No I get the message that this addition has been removed. That makes me angry. I add to Wikipedia as a volunteer without any interest, and I find it simply rude that my work is removed. I can understand that changes are considere critical, but I only made an addition, and removing additions deprives users from potentially useful knowledge. Or is the problem that my addition lacks citations? Being trained both as a lawyer and a physicist, I note that the "deontological" rules on citations vary by discipline. Lawyers like to see footnotes for every word - still it is a rule of legal deontology that general knowledge needs no sources. Here we deal with general knowledge: everyone watching an American weather forecast can acknowledge the statement I added. I will think twice before I make the effort to make other additions to Wikipedia. Rbakels (talk) 21:48, 24 July 2016 (UTC)

European Washing Label
You realise that the 40 refers to 40 degrees Centigrade? Otherwise you're washing in really cold water. — Preceding unsigned comment added by Gomez2002 (talk • contribs) 15:14, 16 August 2016 (UTC)
 * I am shocked! It shows how inefficient washing machines are that a "cold" wash for them is really 104 degrees Fahrenheit.--  Toddy1 (talk) 21:39, 16 August 2016 (UTC)

Wikipedia wrong?
to quote "Many sources (including Wikipedia) will tell you that the Fahrenheit scale was defined by setting zero degrees equal to the temperature of an ice, salt, and water mixture, and 100 degrees is roughly equal to human body temperature. That makes sense, but as the latest episode of Veritasium explains, it's not actually true. The real story is a lot stranger, and a lot more scientific." the source is http://www.sciencealert.com/watch-why-people-still-use-this-crazily-arbitrary-temperature-scale it does make a compelling argument, but I'll leave here for more topic knowledgable editors to consider. Gnangarra 06:19, 4 December 2016 (UTC)
 * Neither that, nor the Youtube video it is based on, is a reliable source. Nor is there any indication where the information came from, so nothing to do here. SpinningSpark 09:59, 4 December 2016 (UTC)
 * I think the Wikipedia article does a reasonable job of covering the uncertain history of the Fahrenheit scale. I might add a bit of detail from Temperature Scales, Fancy and Plain: Roemer and Fahrenheit, "The Science of Measurement: A Historical Survey", Herbert Arthur Klein, 1974. Meters (talk) 18:06, 5 December 2016 (UTC)

External links modified
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Better thermo picture
This is perhaps a better pic, as you can see the C/F scale directly compared without the slight 3-D misalignment of the current picture (which shows inner scale that is slightly offset from the outer scale). http://img-aws.ehowcdn.com/877x500p/photos.demandstudios.com/getty/article/79/119/177089896.jpg — Preceding unsigned comment added by 146.198.113.10 (talk) 16:13, 11 August 2017 (UTC)

Request to incorporate/improve important utility urgently
Please incorporate a table (preferably) like https://www.infoplease.com/science-health/weights-measures/fahrenheit-and-celsius-centigrade-scales but from the wider range like absolute zero (-273 deg celsius~-459 deg fahrenheit) to preferably 200 deg C (~392 deg F), or else at least a more easy to visually compare the scales in an image format (but better than than 2 already used for the article) (like http://abyss.uoregon.edu/~js/glossary/temperature_scale.html) for the same wider scale requested above.

Readers will find it very useful to use it as a ready reference and will be indebted. Thanks. — Preceding unsigned comment added by 116.203.75.254 (talk) 09:37, 22 August 2017 (UTC)


 * Does Conversion of units of temperature have what you want? SpinningSpark 11:55, 22 August 2017 (UTC)

You are right - its already there in the url https://en.wikipedia.org/wiki/Conversion_of_units_of_temperature.

I wish, however, that this url link could be placed inside the section: https://en.wikipedia.org/wiki/Fahrenheit#Usage. Secondly, the url given in the section https://en.wikipedia.org/wiki/Fahrenheit#See_also could either include the urls: 1. https://en.wikipedia.org/wiki/Conversion_of_units_of_temperature#Comparison and 2. https://en.wikipedia.org/wiki/Conversion_of_units_of_temperature#Graphical_representation or else just keep that webpage url: https://en.wikipedia.org/wiki/Conversion_of_units_of_temperature. The reason that the above 2 urls have more complete info to what is being requested.

Thanks for the link. I guess I could have also found that link myself had I done more labour than just looking for what was upfront visible. — Preceding unsigned comment added by 116.203.76.159 (talk) 11:05, 24 August 2017 (UTC)

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From Rømer's scale to Fahrenheit
I made some quick calculation, and I found the history of the derivation of the Fahrenheit scale from the Rømer's one implausible. It a quadruplication of values is performed and then data is tweaked so that water freezes at 32 degrees instead of 30, water would boil at near 250 °F, not 212. Moreover 22.5 °Rø is too low a temperature for the human body: 27.5 °Rø is more acceptable.

I believe that if the story is true Fahrenheit came with 30 °F and 110 °F for freezing water and body temperature and then tweaked it to 32 °F and 96 °F respectively so that this interval was a power of 2. Do you know of any source which may confirm of deny it? --.mau. &#x2709; 21:02, 7 April 2018 (UTC)  — Preceding unsigned comment added by .mau. (talk • contribs)
 * Why would we look for sources to support your conjectures and WP:OR? The article has what appears to be a very solid source for the derivation as given (https://openlibrary.org/books/OL16843401M/The_mechanical_universe). Why don't you get a copy of it and verify it yourself? I don't have that book but I do have a history of metrology book somewhere and as I remember it largely agrees with the history as given. Meters (talk) 21:35, 7 April 2018 (UTC)


 * Ok. It's a fact that Fahrenheit started with a scale where 0 is the bottom, 7&frac12; degrees is the temperature at which water freezes and 22&frac12; degrees is the body temperature. But it is also a fact that this cannot possibly be the Rømer scale where water boiles at 60 degrees; when Fahrenheit multiplies 7&frac12; and 22&frac12; by four, getting 30 and 90 degrees, boiling water would boil at 240 degrees; tweaking the two values to 32 and 96 would put boiling water temperature at 256 degrees, and setting it at 212 is not "somewhat inaccurate". Besides, the article says that brine freezes at zero, water freezes and melts at 7.5 degrees, body temperature is 22.5, and water boils at 60 degrees. and this is plain wrong, unless Rømer scale is not linear. Just do the proportions and look out which is body temperature in Fahrenheit or Celsius.
 * I have an idea about what could have happened; but since conjectures are not welcome - and I agree with this, by the way - I won't state it. I however urge somebody with a better command of English than I have to reformulate that paragraph using the actual source and without making any conjecture about the body temperature in Rømer scale. --.mau. &#x2709; 20:10, 9 April 2018 (UTC)  — Preceding unsigned comment added by .mau. (talk • contribs)
 * I've verified the gist of the version in this article. I'll rewrite it with a better source.
 * Who ever said the Rømer scale was linear? Rømer and the others were inventing the science of making temperature measurements. The only way to make a linear scale with mone or more intermediate reference points is if you already know the exact relationships between the temperatures. In other words, you have to know the reference temperatures before you can make a linear scale. Rømer didn't know the correct body temperature, and so his scale is not linear. Meters (talk) 01:24, 24 July 2018 (UTC)
 * Or you can think of the scale as being linear but the reference points as being inaccurate by today's knowledge. Six of One, a half-a-dozen of the other. Meters (talk) 01:30, 24 July 2018 (UTC)

Fahrenheit Map?
Which of you snarky assholes decided to put the "map of countries with Fahrenheit??"

129.10.9.104 (talk) 00:02, 23 March 2017 (UTC)
 * I do not really see a problem with it. It says the same thing as "Only the United States and its territories use the Fahrenheit scale.", and possibly more effectively for readers that pick up information better from graphics than text. VQuakr (talk) 03:16, 23 March 2017 (UTC)
 * Tsk, americans...--200.120.12.97 (talk) 04:00, 12 July 2017 (UTC)

It's worth noting that the map is actually wrong. The UK, for instance, reports weather temperatures in Farenheit on one side of freezing and Celcius on the other. Silly, but there it is: At least two countries (one unmarked on the map) use Farenheit. IMHO F should be toast, but reality disagrees. Riventree (talk) 07:32, 8 March 2018 (UTC)

I propose the incorrect map be removed until a correct one is produced.

Riventree (talk) 10:15, 20 March 2018 (UTC)


 * Thats not really true about the UK. Offically we use the celsius scale with the temperatures in fahrenheit often given as a supplement - just look at any weather information for the UK. The reason for this is that many older people still have a better idea of what temperatures mean in fahrenheit. Sometimes newspapers will talk about high summer temperatures in fahrenheit because they delight in hyperbole and it sounds hotter that way, but this is getting less common. As the older generation disappears the use of farenheit will go altogether, along with pounds and ounces and feet and inches as younger people will have little use for, or understanding of these terms. Having said that I can't see much point in having a world map that shows farenheit being used in two countries - you can say that in one sentence. Richerman  (talk) 15:44, 20 March 2018 (UTC)
 * Yeah, no. Just because the someone or even some commercial publications still cite the °F scale, does not mean that it is in usage there. The text of the article has the additional nuance. VQuakr (talk) 00:14, 12 May 2018 (UTC)
 * UK Farenheit use has become almost nonexistent now that the generations who grew up using it have died off. The only place you see it is in ridiculous tabloid 'phew what a scorcher' type summer weather headlines, where it appears to be used purely because the numbers are bigger. Almost nobody will know what, say, 92° signifies other than 'hot'. --Ef80 (talk) 13:33, 25 July 2018 (UTC)

Contradictory Definition
It says: "On the Fahrenheit scale, the freezing point of water is 32 degrees Fahrenheit (°F) and the boiling point is 212 °F". Further below, the formula "for an exact conversion" between °C and °F ist given (°F = 9/5 °C + 32). Both statements used to be correct before 1954 when the freezing and boiling points of water were defined as 0 °C and 100 °C. Today, however 0 °C and 100 °C are only approximate values. So only either of these two statements can be exact, but not both. If the conversion formula is exact (is it?), then it must say: "On the Fahrenheit scale, the freezing point of water is approximately 32 degrees Fahrenheit (°F) and the boiling point is approximately 212 °F". -- Wassermaus (talk) 22:08, 5 August 2018 (UTC)
 * The conversion formula is exact indeed - see https://www.nist.gov/pml/weights-and-measures/si-units-temperature. -- 2001:16B8:2E6A:5D00:49B5:A3D1:8C2C:21C8 (talk) 10:54, 7 August 2018 (UTC)

Possible problem with the Fahrenheit Wikipedia page.
Several online sites have stated that the country of India still uses the Fahrenheit temperature scale. Are they all wrong and only Wikipedia right?2602:306:80C1:89E0:D556:5D9:AFE6:2EE7 (talk) 23:40, 1 September 2018 (UTC)
 * Do you have some reliable links/sources? India Meteorological Department uses officially Celsius and this suffices for Wikipedia scope.--Carnby (talk) 12:34, 16 September 2018 (UTC)

Liberia
I can't find reliable sources about the situation in Liberia. Can anyone say it's still officially using Fahrenheit?--Carnby (talk) 15:42, 16 September 2018 (UTC)

Bahamas
Google searches tell me Liberia, Myanmar, Belize and Bahamas still use Fahrenheit. Still true? What were the last few countries to change and when. And why not Bahamas... it’s not a big job (like in the US)? MBG02 (talk) 00:09, 15 September 2018 (UTC)
 * Myanmar/Burma appears to have switched to Celsius in recent times: take a look here; this is not surprising, given the political turmoil the country has suffered: they had more important things to do before telling the world "we use Celsius instead of Fahrenheit." Bahamas seem to use both, with a preference for Fahrenheit: here; I would be not surprised if it's going to change system and I think the choice of keeping Fahrenheit is only due to its proximity to the United States.--Carnby (talk) 12:31, 16 September 2018 (UTC)
 * (I think) it would be good to have some “history” (or stories); list the last few to change, why it took so long (conflict between government, science, industry?); and any kind of story (like a Mars probe failing because they didn’t all use metric). Still curious about Bahamas... considering their British heritage. MBG02 (talk) 21:31, 16 September 2018 (UTC)
 * The situation in the Caribbean is intriguing: I have googled a bit and I discovered not only the Bahamas and the Cayman Islands and are still using Fahrenheit but also other British West Indies (althought in most cases they use also Celsius) and possibly also some former British colonies such as Antigua and Barbuda and so on. The problem is that they are tiny islands that in some cases don't have a proper official meteorological service.--Carnby (talk) 17:02, 17 September 2018 (UTC)

"Salt" vs "ammonium chloride"
It says: "equal parts of ice, water and salt (ammonium chloride)." The article quotes the URL https://www.livescience.com/39916-fahrenheit.html which contains the same statement. However, normally "salt" refers to sodium chloride (NaCl) and not to ammonium chloride (NH₄Cl). Salt (as in sodium chloride) is known to lower the freezing point of water, even below the 0°F temperature, so the question arises whether the quoted author meant sodium or ammonium chloride, and, if sodium chloride, what salt concentration. The text needs to be corrected in any case. Wikiborg4711 (talk) 03:36, 10 November 2018 (UTC)
 * Both are salts — Preceding unsigned comment added by 64.112.182.194 (talk) 17:35, 3 April 2019 (UTC)

Definition via Kelvin
The sentence "The scale is now usually defined by two fixed points: the temperature at which water freezes into ice is defined as 32 °F, and the boiling point of water is defined to be 212 °F, a 180 °F separation, as defined at sea level and standard atmospheric pressure." is misleading. These so- called fixed points are very good approximations, but the exact definition is done via the conversion formulas with degree Celsius and Kelvin.  -- Wassermaus (talk) 07:10, 11 June 2019 (UTC)

But which definition of Fahrenheit is correct?
The article states that Fahrenheit is defined by the freezing and boiling points of water, but then also gives the conversion to/from Celsius. Both cannot be exact. 273.15K and 0°C are no longer exactly the freezing point of water, so either 32°F is defined to be exactly the freezing point of water, or 32°F is exactly 0°C. I have not found an modern authoritative reference defining Fahrenheit to resolve this discrepancy. — Preceding unsigned comment added by Shermanator3 (talk • contribs) 21:47, 4 December 2019 (UTC)
 * According to by NIST the conversion from degree Fahrenheit to degree Celsius and Kelvin has the exact parameters 1.8, 32 and 459.67 - so the freezing and boiling points of water are only approximations.
 * Fahrenheit determined that his zero point to be the freezing point of brine and 100 to be that of the Human body temperature at rest. Looks like his measurements or measuring equipment was off on both counts. So, just as the pound and foot have been redefined with respect to SI Units, the Fahrenheit scale has been redefined by reference to Celsius Kelvin, so that 32°F is precisely the same as 0°C 273 K and 212°F is precisely the same as 100°C 373K. That is how it is defined nowadays. (So it would seem that the article needs to be reviewed). --Red King (talk) 21:19, 25 February 2020 (UTC)
 * Well everybody knows that. Except that I can't find a citation that says so with any authority. (But I did find material to remind me that the SI unit is the degree Kelvin, not Celsius, so I have corrected my note above). The article will have to continue to say what it says until someone else succeeds. I guess it doesn't really matter, if anyone is working to any serious precision, they wouldn't be using Fahrenheit. --Red King (talk) 21:51, 25 February 2020 (UTC)
 * Hi Red King, a correction: the Celsius scale is shifted vs. Kelvin scale by 273.15 exactly (definition), not 273. So 32 °F is exactly 0 °C and exactly 273.15 K;  212 °F is exactly 100 °C  and exactly 373.15 K  (note that there must be a space between the number and °F/°C. Furthermore: both Kelvin (not "degree Kelvin") and degree Celsius are SI Units (see e.g.  table #1 and #2), but Kelvin is the more fundamental one (because it is used for the definition of all others scales and because it is the absolute thermodynamic temperature, i.e. linked to energy by the Boltzmann constant) -- Wassermaus (talk) 22:34, 25 February 2020 (UTC)
 * Yes, I knew that but decided the detail would just confuse the issue. Drawing attention to it does so even more, so clearly I made the wrong call. --Red King (talk) 13:35, 26 February 2020 (UTC)
 * The most authoritative source I could find is, which states that the definition is $t (^\circ C) = {{t(^\circ F) -32 }\over {1.8}}$ or $T (^\circ K) = {{t(^\circ F) + 459.67 }\over {1.8}}$ . AntiCompositeNumber (talk) 01:03, 26 February 2020 (UTC)
 * Yes, there are plenty of sources giving the algorithm for conversion but nowhere could I find any equivalent to the International yard and pound Agreement that formally defined these Imperial/USC measures as being precise fractions of the metre and kilogram. I suspect that no-one considered such a formal rule to be necessary since the IY&P conversions require six decimal places but °F to/from °C is a simple one as noted above. --Red King (talk) 13:35, 26 February 2020 (UTC)

Use in UK media
A recent edit added it is not used in the UK media in 2018. This is not the case. But the saying 'much' may be up for discussion, may some be better wording? --Voello (talk) 04:02, 15 January 2019 (UTC)
 * This has been discussed before. British tabloids have a bizarre practice of reporting high summer temperatures in farenheit because it makes the numbers seem more impressive. This is despite the fact that nobody under 60 has much idea of what farenheit numbers mean. More serious outlets like the BBC and the Guardian stopped quoting farenheit temperatures many years ago even as supplementary info for older people. Farenheit hasn't been used as a primary temperature scale since the 60s. --Ef80 (talk) 09:33, 28 June 2019 (UTC)
 * As of May 2020, the Daily Mail seems to deliberately convert temperatures to Fahrenheit and sometimes the conversions are inaccurate. Perhaps this is due to bloody-mindedness, as there are usually comments asking why the paper refuses to use units that can be understood by people under 65. The Daily Express also gives temperatures in Fahrenheit on a regular basis. More disappointingly I noticed the BBC World News channel (funded by UK licence payers but not officially broadcasted to the UK) giving supplementary Fahrenheit temperatures for the US a few weeks ago. 86.176.27.103 (talk) 23:45, 30 May 2020 (UTC)
 * To be fair to the Beeb, BBC World is an international service with a substantial American audience, so the use of Farenheit equivalents is understandable. --Ef80 (talk) 08:05, 31 March 2021 (UTC)

Nationality of Fahrenheit
I just reverted an edit in the lede which characterized Fahrenheit as German. It's sufficiently complex that I don't think it belongs. He was born to a German-speaking family, which in that day and age made him German, in Pomeria, which was at the time part of the Polish-Lithuanian Commonwealth. He lived his adult life in the Dutch Republic. So there are at least five different nationalities which modern-day sensibilities could ascribe to him. I notice traces of this in other wikis - the German wikipedia says simply German, the Spanish Wiki says Polish-born German, the French wiki in the infobox says Polish, ... My opinion is we should not specifically call out a nationality in the lede, its too complicated for a one-word summary. Tarl N. ( discuss ) 17:49, 16 May 2021 (UTC)

Use in UK
Quoting this article: "Fahrenheit is still commonly used in the United Kingdom in common conversation..."

So shouldn't the map have a different color for the UK? — Preceding unsigned comment added by Asherkobin (talk • contribs) 20:49, 25 March 2021 (UTC)
 * The statement isn't really true and is unreffed. Farenheit hasn't been taught in UK schools since the mid 1960s, and while some people may still think in Farenheit and use it to estimate weather temperatures, they are an elderly and diminishing minority. Farenheit isn't used at all in areas other than weather, for example in cooking. --Ef80 (talk) 08:21, 31 March 2021 (UTC)

This certainly isn't true. Celsius is used for the most part by a great majority of the population as is demonstrated by the medias overall use of celsius (I imagine in general 99% usage but have no statistic to back this up, only experience and knowledge of the country) and the fact that Fahrenheit is extremely rarely used. The usage of Fahrenheit in common conversation doesn't AT ALL ring true to me from young to older generations. This is potentially written by someone with a harkening back to the good old days (emotional reasons) but it's certainly not accurate for an encyclopaedia.

As this is a topic of general usage, it is hard to cite statistics to determine the use of Fahrenheit. However as a Brit, I can assure you Fahrenheit is still commonly used in daily conversation. Typically, in more urban and dense areas such as London or Birmingham, Celsius is used by the majority. However, in more rural areas Fahrenheit is still prominent, to the point where many local news sources still use it regularly alongside Celsius. For instance, a couple years back I was in Cornwall and Devon and the local papers and the news (including the BBC) used both Celsius and Fahrenheit. People under 40 tend to think in Celsius but are more familiar with Fahrenheit than you may expect, due to the consumption of US media as well as interaction with Americans on online platforms. Younger Brits may think of a hot day as 30 degrees C, but will also have rough idea of what weather in the 80s F feels like. Celsius is the temperature scale used by the majority of the population of the United Kingdom, however Fahrenheit is still used regularly.

Unofficialwikicorrector (talk) 20:59, 23 May 2021 (UTC)


 * Indeed. "While historically popular, Fahrenheit is not commonly used in the United Kingdom in daily conversation" is total and utter nonsense (as is the smug and patronising comment "they are an elderly and diminishing minority" above). We use Fahrenheit quite widely in this country.

100°F
Is 100°F related to the body temperature at which a human is considered to have a fever? 173.88.246.138 (talk) 02:55, 15 August 2021 (UTC)
 * Talk pages are for discussion about improvements to the article, not for discussion about the subject. However, if you read the "history" section of the article, you'll find the answer in the first paragraph (96˚F was based on human temperature). Tarl N. ( discuss ) 04:02, 15 August 2021 (UTC)

Temprature scale
How farenhite and celcius are differentiated How they are separated 2409:4072:6E88:C2D6:17F6:2B:4B7C:2052 (talk) 10:46, 9 January 2022 (UTC)
 * Talk pages are to be used for discussing improvements to the article, not generate questions. You might want to visit the Reference Desk to ask questions there for that kind of subject. Tarl N. ( discuss ) 13:21, 9 January 2022 (UTC)

Relation
The article apparently assumes a linear relation between for instance the Celsius and the Fahrenheit scale. Actually it should be discussed why this is the case, if it is anyhow. Madyno (talk) 12:23, 9 August 2022 (UTC)