... because someone needs to do it.
Beginning in elementary school science class, most kids have heard that the use of the Fahrenheit temperature scale is barbaric, antiquated, impractical, and downright antisocial to the rest of the world. And yet our daily exposure to Celsius is for the most part limited to alternating time and temperature readings found on bank clocks on the side of the road. Why?
Go anywhere else in the world, and people will tell you that a 60 degree day can only happen in the Sahara. Even in Canada, so similar to us, a basic use of everyday language is mostly unintelligible. Talk to non-Americans and they are baffled at our continued use of a system where 32 means freezing and 212 means boiling.
32? 212? Who could remember that? Beyond centreing on the properties of water at sea level, there's nothing particularly rational about Celsius. In many ways, it's equal to Fahrenheit, though perhaps less elegant. Consider the following:
1. In scientific applications like thermodynamics, numbers must be expressed in absolutes. Even Celsius must be converted to Kelvins, whereby 0 is absolute zero, freezing is 273.15, and boiling is 373.15. There's nothing scientific or convenient about that. You could do the same thing with a Fahrenheit scale, or you could start over entirely.
2. In everyday usage, Fahrenheit allows the user to be far more precise about the temperature using whole numbers. The equivalent difference between 70 and 80 degrees Fahrenheit is expressed as 21 to 26 degrees Celsius; a roughly 2 to 1 ratio of discrete measurement points in favour of Fahrenheit.
3. For body temperature, right when you want precision, you don't get it. 98.6 degrees Fahrenheit, or 37 degrees Celsius is normal. No argument there. But when 100 degrees Fahrenheit indicates that something is wrong, the equivalent in Celsius is 37.8. Which is more convincing? What about the difference between a 100 and 105 Fahrenheit fever? 37.8 to 40.6 is the difference between life and death in the rest of the world?
4. Unlike the metric system, with its clear advantages over Imperial measures in both precision and ease of use, Celsius is not a base-10 system, nor does it grant its user any real advantage in expressing the subjective feelings brought on by the weather. Even if 20 Celsius is roughly room temperature, and 30 is roughly beach weather, 70 Fahrenheit is roughly room temperature, and 80 gets you in a pair of shorts. 90 Fahrenheit is a warm summer day, while 40 Celsius is blistering.
I accept that Fahrenheit is one of the most annoying examples of American exceptionalism. I certainly betray some embarrassment when I hear of Americans in other countries who can't understand the temperature. It's like not being able to read the time. We can and should do better. If people everywhere can learn 4, 5 or 6 languages, surely there is a place for both systems of temperature measurement here in monoglot America. We could handle a weather forecast that says that a high of 86 is also a high of 30.
But why America in particular? I don't know for sure, but there is a certain style and pragmatism in the everyday use of Fahrenheit that suits the American temperament like none other. We don't need 0 to mean freezing or 100 to mean boiling. We already know what they are as sure as the day is long.
We have an understanding of what a 90 degree day means that provides a silent national cohesion, a reminder that somehow, America is different.
