Meteorology

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METEOROLOGY

METEOROLOGY, the study of the atmosphere and, especially, of weather.

Colonial and Early America

Early settlers in the New World found the climate harsher and the storms more violent than in the Old World. Many colonial Americans kept weather journals but, compared to European standards, few had adequate instruments. The first prolonged instrumental meteorological observations, initiated by Dr. John Lining in Charleston in 1738, were related to his medical concerns.

In 1750 Benjamin Franklin hypothesized that grounded metal rods would protect buildings from lightning damage. Two years later he conducted his famous kite experiment. Franklin's investigations demonstrated that lightning is an electrical discharge and that most flashes originate in clouds. Franklin coined much of the vocabulary of modern electricity, including such terms as positive and negative charge. He was able to simulate many types of lightning damage and demonstrated that lightning rods would protect most structures from such effects. Franklin also suggested that the aurora borealis is of electrical origin and closely associated with terrestrial magnetism, that storms are progressive wind systems, and, on a practical note, that the government should set up an office to administer aid to citizens whose crops or property had been destroyed by hurricanes, tornadoes, blights, or pestilence. During several Atlantic crossings between 1746 and 1775, Franklin made observations of the warm current called the Gulf Stream and was able to chart its boundaries fairly accurately.

Thomas Jefferson and the Reverend James Madison made the first simultaneous meteorological measurements in America in 1778. Jefferson also exchanged observations regularly with his other numerous correspondents. He was a strong advocate for a national meteorological system, and encouraged the federal government to supply observers in each county of each state with accurate instruments. Although these plans did not materialize in his lifetime, within several decades voluntary observing systems were replaced by government-run meteorological services around the world.

The Nineteenth Century

Early in the nineteenth century the Army Medical Department, the General Land Office, and the academies of the State of New York established large-scale climatological observing programs. The information was used in a variety of ways: physicians studied the relationship between weather and health, farmers and settlers used the temperature and rainfall statistics, and educators brought meteorological observations into the classroom.

Between 1834 and 1859 the "American storm controversy" stimulated a meteorological crusade that transformed theory and practice. William Redfield, James Pollard Espy, and Robert Hare argued over the nature and causes of storms and the proper way to investigate them. Redfield focused on hurricanes as circular whirlwinds; Espy on the release of latent "caloric" in updrafts; and Hare on the role of electricity in storms. Espy also prepared the first long series of daily-analyzed weather charts and was the first official government meteorologist of the United States. While it came to no clear intellectual resolution, the controversy of the 1830s and 1840s stimulated the development of observational projects at the American Philosophical Society, Franklin Institute, and Smithsonian Institution. In the 1840s Matthew Fontaine Maury, superintendent of the U.S. Navy's Depot of Charts and Instruments prepared "pilot charts" of ocean winds and currents. The charts, compiled from navy logbooks and reports from ship captains, included sailing directions for mariners on all the world's oceans.

The Smithsonian meteorological project under the direction of Joseph Henry provided a uniform set of procedures and some standardized instruments to observers across the continent. Up to 600 volunteer observers filed reports monthly. In 1849 Henry began compiling weather reports collected from telegraph operators and displayed the results on a large map of the nation. In addition the Smithsonian established cooperative observing programs with the Navy Department, the states of New York and Massachusetts, the Canadian Government, the Coast Survey, the Army Engineers, the Patent Office, and the Department of Agriculture. The Smithsonian sponsored original research on storms, climatic change, and phenology (the study of recurring natural phenomena, especially in relation to climatic conditions); it also published and distributed meteorological reports, maps, and translations. James Coffin mapped the winds of the Northern Hemisphere and the winds of the globe using data collected through Smithsonian exchanges. William Ferrel used this information to develop his theory of the general circulation of the atmosphere. Elias Loomis improved weather-plotting methods and developed synoptic charts depicting winds, precipitation, isotherms, and lines of minimum pressure.

In 1870 Congress provided funds for a national weather service. Assigned to the Signal Service Corps within the War Department, the new service was called the Division of Telegrams and Reports for the Benefit of Commerce. General Albert J. Myer served as the first director of the service, which provided daily reports of current conditions and "probabilities" for the next day's weather. It employed civilian scientists Increase A. Lapham and Cleveland Abbe and more than 500 college-educated observer-sergeants. Its budget increased one hundredfold from 1869 to 1875. The Monthly Weather Review, begun in 1872, was still published in the early 2000s. Beginning in 1875, in cooperation with the weather services of other nations, the weather service issued a Bulletin of International Simultaneous Observations, which contained worldwide synoptic charts and weather observations. In 1891 the U.S. Weather Bureau moved to the Department of Agriculture.

The Twentieth Century

During World War I the bureau instituted the daily launching of upper-air sounding balloons, applied twoway radio communication to meteorological purposes, and developed marine and aviation weather services. The "disciplinary" period in meteorology began rather late compared with parallel developments in other sciences. University and graduate education, well-defined career paths, and specialized societies and journals began in the second decade of the twentieth century. The American Meteorological Society and the American Geophysical Union were both established in 1919.

In the 1930s a number of visiting scientists from Scandinavia, including Vilhelm Bjerknes, Jacob Bjerknes, C. G. Rossby, and Sverre Petterssen brought the new Bergen School methods of air-mass and frontal analysis to the United States. In 1940, to serve the growing needs of aviation, the Weather Bureau was transferred to the Department of Commerce. By this time the use of Bergen School methods and the acquisition of upper-air data by the use of balloon-borne radio-meteorographs had become routine.

During World War II meteorologists instituted crash education programs to train weather officers. Forecasters were needed for bombing raids, naval task forces, and other special operations. Many university departments of meteorology were established at this time. Testing and use of nuclear explosives also raised new issues for meteorologists. Scientists learned that radioactive fallout spreads in an ominous plume downwind and circles the globe at high altitudes in the jet stream. Atmospheric scientists played leading roles in promoting the Limited Test Ban Treaty of 1963, which banned atmospheric nuclear testing. That year, the original Clean Air Act was passed. It was substantially revised in 1970 and in 1990.

Following the war, surplus radar equipment and airplanes were employed in storm studies. At the Research Laboratory of the General Electric Company, Irving Langmuir, a Nobel Prize–winning chemist, and his associates Vincent Schaefer and Bernard Vonnegut experimented with weather modification using dry ice, silver iodide, and other cloud-seeding agents. Although these techniques did not result in their originally intended goal—large-scale weather control—they did provide impetus to the new field of cloud physics. Meanwhile, at the Institute for Advanced Study in Princeton, John von Neumann began experiments using digital computers to model and predict the weather. With the support of the weather bureau and the military weather services, operational numerical weather prediction became a reality by the mid-1950s. Viewing the earth from space had also become a reality. In 1947 cloud formations were photographed from high altitude using a V2 rocket. Explorer 6 took the first photograph of the earth from space in 1959, while in the same year Explorer 7 measured the radiation budget of the earth with a pair of infrared radiometers with spin-scan stabilization designed and built by Verner Suomi. Tiros 1 (Tele-vision Infra-Red Observation Satellite), the world's first all-weather satellite, was launched into polar orbit by NASA in 1960.

Radio weather forecasts date to 1923, when E. B. Rideout began broadcasting in Boston. Televised weathercasts were first aired on the Weather Bureau Dumont Network in 1947 by James M. "Jimmie" Fidler. In 1982 the Weather Channel started round-the-clock cable operations. In 1965 the Weather Bureau became part of the Environmental Science Services Administration (ESSA); it was renamed the National Weather Service in 1970 as part of the new National Oceanic and Atmospheric Administration (NOAA).

Conclusion

New interdisciplinary problems, approaches, and techniques characterize the modern subdisciplines of the atmospheric sciences. Specialties in cloud physics, atmospheric chemistry, satellite meteorology, and climate dynamics have developed along with more traditional programs in weather analysis and prediction. The U.S. National Center for Atmospheric Research and many new departments of atmospheric science date from the 1960s. Fundamental contributions have been made by Edward Lorenz on the chaotic behavior of the atmosphere, by F. Sherwood Rowland and Mario Molina on potential damage to stratospheric ozone by chlorofluorocarbon (CFC) compounds, and by Charles David Keeling on background measurements of carbon dioxide, to name but a few.

Meteorology has advanced through theoretical understanding and through new technologies such as aviation, computers, and satellites, which have enhanced data collection and observation of the weather. Economic and social aspects of meteorology now include practical fore-casting, severe weather warnings, and governmental and diplomatic initiatives regarding the health and future of the planet.