We thought of measurement and its purpose the other day as we read that the tornado in Menasha, Wisconsin, was measured as an “EF-3” storm. It seems somehow a very tidy and comfortable designation for an event that caused such suffering and destruction; surely we should measure such an event on a more human scale. As it happens, however, that’s exactly what the EF scale does do.
As a scale for measuring tornadoes, the EF Scale runs from o to 5, and the designation means “Enhanced Fujita Scale.” The original Fujita Scale was developed by Tetsuya Theodore “Ted” Fujita, a University of Chicago meteorologist, precisely to designate tornadoes by the degree of damage they cause. His work in that and related areas were among the most important developments in the history of meteorology, the study and measurement of weather.
Fujita Tetsuya was born in Kitakyushu City, Japan, in 1920. He took his degree in mechanical engineering in 1943, and by the following year was an assistant professor of physics at the Meiji College of Technology. On August 9, 1945, an American plane was scheduled to drop the atomic bomb designated “Fat Man” on the Kokura railway, a few miles from Professor Fujita’s home, but because of cloudy weather it turned instead to Nagasaki. In the aftermath, the Japanese government asked Professor Fujita to investigate what had happened. By using the burn shadows on the insides of bamboo stakes used to place flowers in Nagasaki cemeteries, he was able to determine the location and height of the bomb at the moment of detonation.
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An F-3 tornado, for instance, is characterized in the original scale by “roofs and some walls torn off well-constructed houses; trains over-turned; most trees in forests uprooted; heavy cars lifted off ground and thrown.” While we may tend to think of storms in terms of wind speed, the Fujita Scale, and its update, the Enhanced Fujita Scale, is still an estimate, and not a measurement, of wind speed, based on the observable effects of the wind, and not the other way around. It is the accounting of the damage, and not the damager, that forms the basis of the scale.
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Professor Fujita’s work came at a time when great leaps in technology had become available for the observation and measurement of ordinary human life and the phenomena around us. Advances in satellite photography, radar observations, and airflight technology and instrumentation, had made the calculation of standardized measurements on a broad scale easier than had been previously imaginable. But consider this: It was not a radar map or super-anemometer that formed the idea of an EF-3. It was not the power of technological measurement and calculation alone that gave order and understanding to this aspect of our world, thereby sparing thousands of lives. It was the very human powers of a man’s well-trained mind and imagination.
As one of Professor Fujita’s colleagues explained after his death in 1998, “He had a way to beautifully organize observations that would speak the truth of the phenomenon he was studying.”
And that is perhaps the most human way of measuring things.