Listen: Why Does America Use Fahrenheit Instead of Celsius?
"Today's episode is brought to you by the podcast food three sixty host mark murphy celebrity chef and run tour with help from his friends. The restaurant industry takes a three sixty. Look at the world food food history science and culture tuned into food three sixty with new episodes every friday could listen and subscribe on apple podcasts iheartradio app or wherever you get your podcasts look to brain stuff production of iheartradio brain stuff lauren boban here. If you're an american you've ever ever had a conversation with someone from another country about the weather. You've probably been a little confused when he or she said the afternoon. Temperature is a nice twenty one degrees to to you that might sound like a chilly winter day but to them. It's a pleasantly warm springtime temperature. That's because virtually every other country throughout the world uses the celsius temperature scale part of the metric system which denotes the temperature at which water freezes as zero degrees and the temperature at which boils as one hundred degrees but the u._s. u._s. And a few other holdouts the cayman islands the bahamas believes in palo clinging to the fahrenheit scale in which water freezes at thirty two degrees and boils at two hundred and twelve twelve that means that the twenty one degrees celsius temperature that we previously mentioned is the equivalent of a balmy seventy degrees fahrenheit in the united states. The persistence of fahrenheit is one of those puzzling american idiosyncrasies like how the u._s. uses the word soccer to describe what the rest of the planet calls football so why is it that the u._s. Us uses a different temperature scale and why doesn't it switch to be consistent with the rest of the world. There doesn't seem to be a logical answer except perhaps inertia americans generally. I don't really seem to distrust the metric system. A twenty fifteen poll found that just twenty one percent of the public favoured converting to metric measures while sixty four percent were opposed it might make more sense of fahrenheit was old school in celsius with some modern upstart a sort of the new coq of temperature but in reality they were created only about two decades apart part fahrenheit was created by its namesake. A german scientist named daniel gabriel fahrenheit who in the early seventeen hundreds was the first known person design alcohol and mercury thermometers that we're both precise and consistent so that any of his instruments would register the same temperature reading in a given place at a given moment thanks to his working skill in managing glass when fahrenheit started out the key thing he was interested in was coming up with the same temperature reading all the time not comparing temperatures of different things or different times of day but when he presented a paper on his system for measuring temperature to the royal society of london in seventeen twenty four he apparently realized that he had come up with the standard temperature scale as well. We spoke with don hilfiger a research meteorologist to colorado state university's cooperative institute for research in the atmosphere and and also president of the u._s. Metric association a group that advocates conversion to the metric system he explained basically the fahrenheit scale was devised a zero as the coldest oldest temperature for a mix of ice and salt water and the upper end was thought to be body temperature approximately ninety six degrees fahrenheit making a scale that could be progressively divided by two do this resulted in the freezing melting temperature being thirty two degrees fahrenheit not very useful number. The boiling temperature for water was then set at two twelve again not not a very useful number the temperature's one hundred and eighty degrees apart again a multiple of two nevertheless the system apparently sounded pretty good to officials officials of the british empire who adopted fahrenheit as their standard temperature scale which is how eventually became established in the american colonies. Well meanwhile though in seventeen forty forty two a swedish astronomer named anders celsius came up with a less unwieldy system based on multiples of ten in which there was precisely a one hundred degree difference between the freezing and boiling temperatures of water at sea level the neat one hundred degrees symmetry of the celsius scale made it a natural fit for the metric system which was formerly developed by the french in the late seventeen eighteen hundreds but the english speaking world nevertheless clung stubbornly to its preference for awkward units such as the pound in the inch and fahrenheit went along for the ride but finally in nineteen sixty one the u._k. Met office then called the u._k. Meteorological office switched teasing celsius to describe temperatures in weather forecasts in order to be consistent with other european countries. Most of the rest of the world soon followed suit with the notable exception of the u._s. Or the national weather service still publishes temperature data atta in fahrenheit. Even though its own staff long ago switched celsius hilter explained the n._w._s. Catering to the public by reporting in degrees fahrenheit whereas whereas much of their operations such as forecast models used degrees celsius and automated weather observations the temperatures recorded in celsius as well should we choose to metric chicken weather reports the fahrenheit layer. That's now added for the u._s. Public could be removed. We also spoke via email with jay hendrix who heads the u._s. National institute standards and technologies thermodynamic meteorology group he points out that the fahrenheit scale does have one significant advantage quote. It has more degrees over the range range of ambient temperatures that are typical for most people. This means that there's a finer grain temperature difference between seventy degrees fahrenheit and seventy one degrees fahrenheit then there is between twenty one degrees celsius twenty two degrees celsius since a human can tell the difference of one degree fahrenheit. This scale is more precise for the human experience on the other hand though the advantage goes away. If a fractional temperature in celsius used hendrix explained for example the equivalent celsius temperature for seventy and seventy ninety one fahrenheit are equivalent to twenty one point one and twenty one point seven degrees celsius. Today's episode was written by patrick j tiger and produced by tyler clang brainstorms production of iheartradio's. How stuff works for more on this and lots of other topics that humans are sensitive to visit our home planet. How stuff works dot com and from our podcast iheartradio visit the iheartradio app apple podcasts or wherever you listen to your favorite shows they i would much rather story that you tell off. My daughter was beaten to death. I'm katherine townsend host of the true crime podcast helen one gone and i'm heading back to arkansas on a new case to find out what happened to janey ward on september ninth nineteen eighty nine when there's no justice done it hurts. A lot of people floors listened to hell and gone. That's h. E. l. l. and gone on apple podcasts or on the iheartradio app or wherever you get your podcasts."