Electrical and computing technologies have greatly enhanced the ability to warn of impending natural disasters. Before electrical communications, a severe storm simply traveled faster than observers could warn of its formation.
The invention of the telegraph stimulated the formation of networks of weather observers. In 1848, James Pollard Espy of the Franklin Institute, in Philadelphia, helped establish a network of observation stations to report weather conditions. The following year, the Smithsonian Institution, in Washington, D.C., supplied weather instruments to telegraph companies so they could transmit information over an extensive observation network. In 1868, Cleveland Abbe, director of the Cincinnati Astronomical Observatory, suggested that warnings should be issued three days in advance for storm systems and six hours for hurricanes.
In 1883, astronomer Edward Holden, director of the Washburn Observatory at the University of Wisconsin, in Madison, proposed an electrical warning system for tornado-prone areas. It would have depended on an arc of telegraph wire to the south and west of a town (tornadoes in the Northern Hemisphere typically travel from the southwest to the northeast) at a radius of 3 to 4 kilometers.
Grounded at each end, the wire was to be connected to the local telegraph office and have drop-offs at houses along the way. Each house would have been outfitted with an apparatus containing a bell that used a coiled spring (similar to one in an alarm clock) and an electromagnet that would have prevented the bell from ringing as long as current flowed through the wire. A battery at the telegraph office would have kept a constant current passing through the line. But if an approaching tornado snapped the wire, the current would have stopped and the bell would have rung, warning residents to take shelter.
Not only was the system never built, but also use of the word tornado in weather forecasts was banned by the U.S. Weather Bureau from 1885 to 1938. The bureau feared it would panic people or discourage them from settling in tornado-prone areas. What’s more, business owners complained of the financial losses caused by tornado warnings when customers and employees stayed home and took shelter. Despite such misgivings, an experimental tornado-warning program began using radio in 1943 to alert listeners in St. Louis and Kansas City, Mo., and in Wichita, Kan. In 1948, a radio broadcast warned of a tornado that touched down near a residential area of Wichita. The tornado caused a lot of destruction but no fatalities.
Even though lives were undoubtedly saved, businesses complained. H.M. Van Auken, general manager of the Wichita Chamber of Commerce, denounced the broadcast. He criticized the Weather Bureau for creating “unfavorable publicity” and jeopardizing the community’s industrial development by using the word tornado. Even after the Weather Bureau lifted its restriction on using that word in a weather report, the Federal Communications Commission continued for another 16 years—until 1954—to ban television and radio from broadcasting tornado warnings.
But technology marched on. Developments in radar and in computer modeling led to the next major advances in the detection and warning of severe weather.
ON TO RADAR
In 1946, the U.S. Army Signal Corps began modifying surplus World War II gun-laying radars for use in weather detection. The Weather Bureau commissioned its first weather radar in 1947. The following year, two Air Force officers, Capt. Robert Miller and Maj. Ernest Fawbush, observed that weather conditions around Tinker Air Force Base, in Norman, Okla., were similar to conditions that had spawned a tornado in the area. They then tracked an approaching storm on radar and were able to issue a warning before the tornado touched down.
As radar technology improved, so did severe-weather predictions. In 1953, Glenn Stout and other engineers at the Illinois State Water Survey, in Champaign, noticed a distinctive hook-shape echo on their radar screens and were able to correlate it with a tornado.
Japan’s Mount Fuji Weather Radar System is an example of a sophisticated detection and warning apparatus. Almost immediately after it began operation in 1964, it detected an approaching typhoon more than 800 km away. The radar system, which was planned by the Japan Meteorological Agency and built by Mitsubishi Electric Corp., was named an IEEE Milestone in 2000.
In 1971, 10-centimeter pulsed Doppler radars became operational. Such radars were designed to detect anything that moves and measure its velocity. Because the radars can measure relative wind velocities, they are able to detect tornadoes even when the hook signature itself is not visible. They cannot show whether the vortex is aloft or touching the ground, however. At about that time, seismographs—long used for detecting earthquakes—were being developed to detect the characteristic vibrations produced by a tornado funnel when it touches the ground.
Satellite-based remote-sensing systems, which became more advanced in the 1980s, have also been used for the detection and warning of disasters, including floods and tsunamis.
The IEEE History Center, which contributed this article, is funded by donations from institutions and individuals.