Welcome to brain Stuff production of iHeart Radio. Hey brain Stuff, Lauren bog Obam Here. If you're an American and you've 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 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 it boils as a hundred degrees, but the US and a few other holdouts the Cayman Islands, the Bahamas, Belize, and Palau, cling to the fahrenheit scale, in which water freezes at thirty two degrees and boils
at two hundred and twelve. That means that the twenty one degrees Celsie's 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 US uses the word soccer to describe what the rest of the planet calls football. So why is it that the 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 seemed to distrust the metric system. A fifteen pole found that just one of the public favored converting to metric measures, while sixty four percent were opposed. It might make more sense if Fahrenheit was old school and Celsius was some modern upstart, sort of the new Coke of temperature, but in reality
they were created only about two decades apart. Fahrenheit was created by its namesake, a German scientist named Daniel Gabriel Fahrenheit, who in the early seventeen hundreds was the first known person to design alcohol and mercury thermometers that were both precise and consistent, so that any two 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 to come up with a standard temperature
scale as well. But we spoke with Don Hilger, a research meteorologist at Colorado State University's Cooperative Institute for Research in the Atmosphere 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 was zero as the coldest temperature for a mix of ice and salt water, and the upper end was thought to be body temperature approximately nine degrees fahrenheit, making a scale that
could be progressively divided by two. This resulted in the freezing melting temperature being thirty two degrees fahrenheit, not a very useful number. The boiling temperature for water was then set at two twelve, again not a very useful number. The two temperatures are a hundred and eighty degrees apart
again a multiple of two. Nevertheless, the system apparently sounded pretty good to officials of the British Empire, who adopted fahrenheit as their standard temperature scale, which is how eventually
became established in the American colonies as well. Meanwhile, though, in seventeen 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 formally developed by the French in the late seventeen hundreds, but the English speaking world nevertheless clung stubbornly to its preference for awkward units such as the pound and the inch, and fahrenheit went along for
the ride. But finally, in nineteen sixty one, the UK met Office then called the UK Meteorological Office, switched to using 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 US, where the National Weather Service still publishes temperature data in fahrenheit, even though its own staff
long ago switched to celsius. Hilder explained the NWS as catering to the public by reporting in degrees fahrenheit, whereas much of their operations, such as forecast models, use degrees celsius, and for most automated weather observations the temperatures are recorded in celsius as well. Should we choose to go metric and weather reports, the fahrenheit layer that's now added for the u S public could be removed. We also spoke via email with j Hendrix, who heads the u S
National Institute of Standards and Technologies Thermodynamic Meteorology Group. He points out that the fahrenheit scale does have one significant advantage a quote. It has more degrees over the 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 than there is between twenty one degree celsius and twenty two degree 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 is used. Hendricks explained. For example, the equivalent celsius temperature for seventy and seventy one fahrenheit are equivalent to twenty one point one and twenty one point seven degrees celsius. Today's episode was written by Patrick Jake Tiger and produced by Tyler Clang. Brain Stuff is
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