 Did
you know that from 1885 until 1938, prior to the advent of radar, the
U.S. Weather Bureau banned the use of the word 'tornado' in weather
forecasts? According to a story in the September 2013 edition of IEEE's
Spectrum magazine, the bureau thought the mere mention
of the word would strike fear in people and prevent them from settling
in tornado-prone Midwest and western plains regions. Believe it or not,
the decision was made in part because local business owners complained
that customers stayed home in shelters rather than shopping at their
establishments when a tornado warning was in effect. An early tornado
warning system was devised that was so hokey that it is no surprise
it never worked well enough to be adopted. A single wire with a series
current running through it was strung between all the houses and along
a stretch of land southwest of town (most probable approach direction
of tornados). The current energized a solenoid that held cocked the
hammer of a bell. If a tornado broke the wire anywhere, the bells in
all outfitted homes would strike to warn occupants of immediate danger.
I suppose it was better than nothing, but not very practical or effective,
especially if a stray cow or mischievous kid broke the wire.
In 1948, a rudimentary radio broadcast warning system based on a
network of observers and reporters debuted in parts of Kansas and Missouri
that did prove useful, albeit labor intensive. In 1946, the U.S. Army
Signal Corps, responsible for all forms of communications during wartime,
began converting some of their World War II era radar systems for
use in weather detection. The first official weather radar was commissioned
a year later. U.S. Air Force officers Capt. Robert Miller and Maj. Ernest
Fawbush, noticed that the atmospheric conditions surrounding Tinker
Air Force Base in Oklahoma visibly appeared similar to the way it did
during the onset of prior tornadoes in the area. They used radar to
monitor the approaching storm and were able to discern a telltale signature
in the signal that correlated with the spawning of a tornado. In 1953,
researchers identified a distinctive hook-shaped echo which was found
to be characteristic of a fully formed tornado. The era of severe weather
forecasting via radar had been born. In 1971, S-band pulse-compression
radar systems that could detect and measure the velocity of anything
that moves became operational. Software algorithms produced the kind
of color-coded weather radar images that we are accustomed to seeing
today. Satellite sensing is now combined with terrestrial data to provide
an up-to-the-minute status on everything from a list mist of rain to
a major downpour, ice storm, or blizzard-force snow storm. Phone apps
like
Dark Sky now exploit instant access to the National Weather Service's
publically available database to let you know based on your current
GPS-determined location whether or not to head for shelter. We've come
a long way, baby. 
Here is a related CNN story titled "Up
Until 1940s, Americans Didn't Even Get Tornado Forecasts."
Posted September
12, 2013 |
