Weather Whys; Fahrenheit and Celsius

Weather-wise, in the United States, surface air temperature is most often reported in degrees Fahrenheit, but the rest of the world generally uses the Celsius scale. These days it's common to see bank thermometers displaying the temperature in both Fahrenheit and Celsius. That's why you might see the bank sign flashing 40 degrees on an oppressively hot day. As it works out, 40 degrees on the Celsius scale is about 104 degrees Fahrenheit. The Fahrenheit scale was developed in the early 18th century by Daniel Fahrenheit, who combined ice, salt, and water to achieve the coldest temperature he could. The ice cooled the water, but the salt allowed the mixture to remain liquid at a much lower temperature than water alone could. He placed a thermometer in the mixture and marked the lowest point reached by the liquid in the tube. He called that point zero. He chose some arbitrary units of length to measure how high the liquid in the thermometer rose in its tube.

Those were called degrees Fahrenheit. Working up from zero, he found the freezing temperature of water was 32 units. The boiling point of water was at 212. That's why we can say water boils at 212 degrees and freezes at 32 degrees Fahrenheit. But later in the century, another scale was introduced. It assigned the temperature zero to the freezing point of water and 100 to its boiling point. It also includes 100 equal units between the freezing and boiling marks. That scale was called centigrade, meaning a scale of 100. But it was later renamed Celsius after its inventor. Celsius is now the preferred scale for scientific work, even though most Americans still use the Fahrenheit scale for everyday purposes. Water wise was created by William Beasley, with original music by Barry Stram. For weather wise, I'm Drew Barlow.