User:WeatherWriter/Tornadic research

First tornadic case study

The first case study on a tornado took place following the violent 1764 Woldegk tornado, which struck around Woldegk, Duchy of Mecklenburg-Strelitz, Holy Roman Empire (modern-day Germany).^[10] Between 1764 and 1765, German scientist Gottlob Burchard Genzmer published a detailed survey of the damage path from the tornado. It covers the entire, 33 km (18.6 mi) long track and also includes eyewitness reports as well as an analysis of the debris and hail fallout areas. Genzmer calls the event an "Orcan" and only compares it to waterspouts or dust devils.^[11][12] Based on the damage survey, modern day meteorologists from the ESSL were able to assign a rating of F5, on the Fujita scale, and T11 on the TORRO scale, making it the earliest known F5 tornado worldwide.^[10] The T11 rating on the TORRO scale also places this event among the most violent tornadoes ever documented worldwide.^[10]

First studies by country

In May 1820, Józef Karol Skrodzki, Professor at the University of Warsaw, read a paper describing a tornado that occurred in Mazew, Łęczyca County in Poland on August 10, 1819. It was described that the tornado had the appearance of a funnel whose color seemed different depending on the lighting, and that it damaged several buildings by tearing off roofs, damaging the structure, and lifting a hay wagon into the air. The paper was published in a collection of works by the Warsaw Society of Friends of Learning in 1821.^[13][14]

In 1838, the earliest recorded Asian tornado struck near the city of Calcutta in present-day West Bengal, India. It was described as moving remarkably slow across its 16-mile (26 km) path southeast over the span of 2 to 3 hours. It was recorded to cause significant damage to the area, including 3.5-pound (1.6 kg) hail being observed at the Dum Dum weather observatory.^[15]

Between 1839 and 1841, a detailed survey of damage path of significant tornado that struck New Brunswick, New Jersey, on June 19, 1835, which was the deadliest tornado in New Jersey history, occurred. The path was surveyed by many scientists on account of its location between New York City and Philadelphia, including early tornado theorists James Pollard Espy and William Charles Redfield. Scientists disagreed whether there was whirling, convergent, or rotational motion. A conclusion that remains accurate today is that the most intense damage tends to be on right side of a tornado (with respect to direction of forward movement), which was found to be generally easterly).^[16][17]

In 1840, the earliest known intensive study of a tornadic event published in Europe, by French scientist Athanase Peltier.^[18] In 1865, the first in India and earliest known scientific survey of a tornado that analyzed structure and dynamics was published by Indian scientist Chunder Sikur Chatterjee. The path damage survey of a tornado that occurred at Pundooah (now Pandua), Hugli district, West Bengal, India, was documented on maps and revealed multiple vortices, the tornadocyclone, and direction of rotation,^[19] predating work by John Park Finley, Alfred Wegener, Johannes Letzmann, and Ted Fujita.

Tornadogenesis

Tornadogenesis is the process through which a tornado forms. Since the late 1890s, theories regarding how tornadoes formed have been published, but the complexity and dangers of tornadoes mean the intricacies of how tornadoes form is difficult to research and prove.

In December 1898, Dr. B. F. Duke, along with Dr. Cleveland Abbe, published a paper regarding the United States's Weather Bureau's first official theory on how tornadoes form after Duke observed the formation of a tornado near Pascagoula, Mississippi, in April 1894. This theory included that winds have to be moving in two different directions ("northerly and southerly") and that when those winds meet, they form a rapid updraft, which forms a very buoyant cloud. The buoyant cloud then will "suck up the air beneath it with such violence as to form a waterspout over the ocean or a tornado over the land and the winds immediately below it are suddenly and greatly increased". Dr. Abe then theorized that "it is possible that we may have violent whirls with horizontal axes", for the first theory of horizontal vortices within tornadoes.^[20]

In March 1913, M. E. Durand-Gréville, a European meteorologist, published a paper about squall lines and tornadoes and presented it before the International Conference of Directors of Meteorological Observatories. The research presented by Durand-Gréville regarding how tornadoes can form in any "squall-zones" of squall lines, which can be detected through barometers. Durand-Gréville's research led to the creation of the "law of squalls" as well as the creation of the International Commission on Clouds, a new international organization of the International Meteorological Organization, the predecessor of the World Meteorological Organization.^[21]

Definitions

In January 1918, Alfred J. Henry, a meteorologists at the U.S. Weather Bureau, published the Bureau's official definition of a tornado as "a violent windstorm accompanied by rain, hail, thunder, and lightning, in which the air masses whirl with great velocity about a central core while the whole storm travels across the country in a narrow path at a considerable speed".^[22]

Characteristics of tornadoes

In April 1899, Dr. Cleveland Abbe, along with Professor A. W. Baker and E. L. Dinniston, published an article regarding the characteristics of tornadoes. In the study and analysis, Abbe discovered that tornadoes in the United States rotate counterclockwise, just the same as a large low-pressure system. Abbe also stated that this rotation rule for tornadoes "is almost invariable".^[23]

In January 1918, meteorologist Alfred J. Henry, described the U.S. Weather Bureau official position on the characteristics of tornadoes, saying, they "have a destructive diameter of from a few hundred feet to half a mile and sometimes more. When seen from a distance the tornado has the appearance of a dense cloud mass with one or more pendant funnel-shaped clouds which may or may not reach to the earth. In the larger tornado clouds east of the Mississippi the funnel cloud may not be noticeable unless the observer be situated in a favorable position for observing it, but the whirling motion of the air is the same whether the funnel is visible or not".^[22]

Tornado watches and warnings

In April 1899, the Chicago Tribune wrote to the United States Weather Bureau via a news article posing the question on why tornado warnings are not sent out via telegraphs or even the telephone to warn the local population in the path. Cleveland Abbe responded by saying "it is certain that if any such arrangement were possible, the Weather Bureau would have done this many years ago" along with "we must remember that the destructive areas of tornadoes, and even of thunderstorms, are so small that the chance of being injured is exceedingly slight" and that "we do not attempt to prevent that which is inevitable". They also wrote that the change of being injured by a tornado is "one in ten thousand years".^[24]

In June 1899, U.S. Weather Bureau Oklahoma section director J. I. Widmeyer published that long-range forecasters in Oklahoma were sounding "unnecessary tornado alarms" due to "ignorant predictions" to residents in Oklahoma and that they were causing "frightened men, women, and children" to take shelter, despite no tornadoes occurring. Cleveland Abbe added on to the publication by Widmeyer saying, "it is unnecessary to resort to the caves and cellars, or to stop our ordinary avocations for fear of a tornado, until we see the cloud in the distance, or are positively certain that one is about to pass near us".^[25]

In April 1908, the U.S. Weather Bureau published several replies regarding a question posed to the Weather Bureau on: How can we protect against tornadoes?.^[26]

• Lieutenant John Park Finley responded with "the best we can do is to watch the distant tornado, and if it seems to approach us then move away toward the left; so far as we have learned, this still continues to be the best rule".^[26]
• The Chief of the Weather Bureau responded with the idea to establish a warning system by surrounding a city at a distance of 4 mi (6.4 km) with wires hooked up with alarms. That way, a warning can be given to the city for an impending tornado. The wire system would detect sudden pressure differences, if wires were twisted, or if wires were short circuited. It was also stated that at a distance of four miles from the city, the tornado "would be unable to reach the city from any direction without giving us an alarm".^[26]
• Cleveland Abbe responded by saying the idea of a wire-based system around a city is not practical as well as how tornadoes are very infrequent. Abbe ended by saying that "the mere forewarning of a tornado is no protection against its coming" and that it would be wiser to "spend your money to protect yourself against diseases, accidents, lightning, ect…".^[26]

In March 1913, M. E. Durand-Gréville, a European meteorologist, published a new tornadogenesis method, and pushed the International Meteorological Organization, the predecessor of the modern World Meteorological Organization, to develop tornado warnings for tornado-producing "squall-zones" in squall lines, with detection "at least several houses in advance" being possible in the United States and France.^[21]

Pressure and velocity

In 1896, H. C. Frankenfield, an employee at the United States Weather Bureau's office in St. Louis, conducted a case study on the 1896 St. Louis–East St. Louis tornado, which included a damage survey and meteorological analysis of the tornado and associated storm.^[27] Following the study by Frankenfield, a special case study was conducted by Julius Baier, a civil engineer in St. Louis to address an estimation made by Frankenfield. In his study, Baier stated that the tornado's center crossed directly over a barometer, which recorded a reading of 671 millimetres of mercury (895 mb). In the study, it was also documented that Baier, along with professor F. E. Nipher, tested the barometer and saw no apparent ways of an inaccurate reading, marking the first accurate pressure reading inside a tornado.^[28]

Following an analysis and survey of the July 1899 New Richmond tornado, B. F. Groat and Peter Christianson, mechanical engineering professors at the University of Minnesota, published a formula to show the relation between a tornado's pressure and a tornado's wind speed velocity: ${\displaystyle P}$ = 0.005${\displaystyle V}$². Using this formula, they determined the tornado had a minimum wind speed of 134 miles per hour (216 km/h), marking the first time a tornado's wind speed was able to be estimated using forensic engineering methods.^[29]

English Wikisource has original text related to this article:

"Wind Force in Tornadoes" by Frank H. Bigelow

In 1901 and later again in 1906, Frank H. Bigelow, chief of the United States Weather Bureau, calculated and published formulas to find the rotational speed of a tornado based on the height above sea level. In his study, Bigelow studied a waterspout off the coast of Cottage City, Massachusetts.^[30][31] Bigelow's formula went on to help Alfred Wegener, a leading geophysicist, atmospheric scientist, and an Arctic explorer, develop the hypothesis that tornadoes can form off of a gust front.^[32]

In January 1906, Dr. J. P. Gibson, an employee at the United States Weather Bureau's office in Salisbury, North Carolina, published an analysis of the damage caused by a tornado on June 12, 1905, in the town of Mooresville, North Carolina. The tornado destroyed a large 8,000 square feet (740 m²) auditorium. Dr. Gibson concluded the extreme low air pressure from the tornado destroyed the auditorium, not the actual force of winds produced by the tornado, but "but mainly the expansion of the confined air", marking the first theory regarding a tornado's low pressure being the root cause of damage caused by tornadoes.^[33]

Frequency and locations

In June 1897, Cleveland Abbe, a PhD meteorologist and professor at Columbian University, published one of the first tornadic frequency tables for each state in the United States, which included the annual average per state as well as the average per 10,000 square miles (26,000 km²). In the table, it was noted that Kansas was the leading state for tornadoes, with an annual average of 6.38 tornadoes, followed by Illinois with an annual average of 4.94 tornadoes. The only states documented with an annual average of 0 tornadoes was Alaska, Delaware, Idaho, Oregon, Rhode Island, Utah, and Washington.^[34]

In April 1899, Abbe published an article along with the Iowa State Register and Iowa Weather and Crop Service, stated the number of tornadoes across the United States was not truly increasing and that any numeric increase in tornado count was strictly due to the increase of newspaper and telegraph coverage in the United States. It was also stated that tornadoes are now documented almost entirely within 24-hours, so no meteorological phenomenon is causing an increase in tornado counts. Abbe also stated anything to the contrary was a "popular mistake".^[35]

Sound

In February 1898, J. J. O'Donnell, an observer for the United States Weather Bureau, published a detailed meteorological case study and damage analysis on a violent tornado which struck Fort Smith, Arkansas, on January 11–12, 1898. Prior to being struck by the tornado, O'Donnell observed a barometer which read a pressure of 28.846 inches of mercury (976.8 mb). O'Donnell also recorded the order-of-sequence of what an approaching tornado sounds like: "a gurgling noise...like water rushing rushing out of a bottle, followed immediately by a rumbling, such as that made by a number of heavy carriages rolling rapidly over a cobblestone pavement, and finally like a railroad train." O'Donnell later stated these three sounds, in sequence is the "tornado roar".^[36] This sequence of sounds documented by O'Donnell, particularly the sound of a train, is the described sound of a tornado by people, even in the 21st century.^[37]

Temperature