Weather instruments offer precision reference
Galileo Galilee, one of the most well-known Italian mathematicians and philosophers, invented a simple thermometer in 1593. In his library Galileo kept a glass bulb, about the size of a chicken egg, filled with a clear liquid and with a thin tube sticking out of the top. He and his friends watched the liquid inside the tube rise and fall as the temperature changed. Galileo correctly calculated that the volume of the liquid would expand as it warmed and shrink as conditions cooled. Believe it or not, his invention wasn’t widely used.
It was more than 120 years later in 1714 that the first really precise thermometer was introduced by German physicist Gabriel Daniel Fahrenheit. He developed a scale where water boils at 212 degrees Fahrenheit and freezes at 32 degrees Fahrenheit.
A generation later in 1742, Swedish astronomer Anders Celsius devised a new scale of measuring temperatures that is widely used today, except in the U.S. The boiling point of water on the Celsius scale is 100 degrees and the freezing mark is 0 degrees.
To determine when and how severe each period of global warming or cooling occurred thousands of years ago, scientists have used lakebed “bathtub ring” readings, tree-ring data (dendrochronology), glacial ice core samples, ancient writings from the Chinese, various Indian tribes and others. No precise measurements can be provided, but we do have a good idea of the intensity of alternating warming and cooling cycles on Earth during the past 45 to 50 centuries.
Before the days of thermometers and barometers, history’s amateur weather-watchers could only describe the types of meteorological events they were enduring and the many weather-related hardships they faced daily.
The first meticulous, routine weather observations in Europe were established by church bishops in London in the early 1600s. They reported in 1609 that “the Thames River froze so solid that even elephants could cross it!”
The first precise weather diary kept on a daily basis in North America was by a Lutheran minister, the Rev. John Holm. His observations were taken near what is now Wilmington, Del.
George Washington kept a daily weather diary for more than 30 years. He frequently called the weather “very cold, very warm, very snowy or very wet.”
Thomas Jefferson reportedly took a break from writing the Declaration of Independence by going out and buying a thermometer. Soon thereafter, he purchased a barometer. For more than 50 years, Jefferson kept a daily weather diary so detailed that it was later praised by the U.S. Weather Bureau that was founded in 1870.
But, the most famous of all U.S. weather-watchers was undoubtedly Ben Franklin, who told his friends to “go fly a kite!” Franklin had five thermometers and a barometer in his library.
As far as our near-term weather is concerned, I still see additional afternoons with readings in the 90s and, perhaps, another day or two with triple-digit heat between now and early August.
Precipitation should be limited to widely-scattered afternoon or evening thunderstorms, especially near the mountains. The area received some much-needed rainfall from one of those thunderstorms last week, but precipitation overall, as measured at Spokane International Airport, is still slightly less than 70 percent of normal.
Shower activity should increase by mid- to late August and conditions should turn even wetter and cooler than normal beginning around mid-September. Early September may see one last gasp of summer as temperatures climb into the 90s.
Meteorologist Randy Mann can be seen weekends on KREM-2. If you have any questions or comments, you can contact him at randy@longrangeweather.com, or go to www.longrangeweather.com for additional information.