History of Meteorology

and wind instruments

Prepared by: Julie ann andayaBsed i-b

Meteorology - the study of the atmosphere and it's phenomena

First discussed by Aristotle, 340 B.C.

wrote a book entitled Meteorologica - summarized meteorological knowledge to date

•17th-18th centuries - meteorology came into being with the advent of met instrumentation such as thermometers and barometers•19th century - met observations were being made routinely - transmitted with the telegraph

•  1920's - Concept of airmasses and fronts was formulated in by Norwegian meteorologists

They developed a theory for the evolution of mid-latitude cyclones - still used today!!

•After WWII - meteorological radars were implemented•1950's - computers ran first models of the atmsophere•1960's - first meteorological satellites were launched (Tiros I )•1990's - National Weather Service was modernized

Weather instruments By definition the weather is "the state of the atmosphere at a given time and place, with respect to variables such as temperature, moisture, wind velocity, and barometric pressure

anemometerWind velocity or speed is measured by a cup anemometer, an instrument with three or four small hollow metal hemispheres set so that they catch the wind and revolve about a vertical rod. An electrical device records the revolutions of the cups and calculates the wind velocity. The word anemometer comes from the Greek word for wind, "anemos

hemispherical cup anemometer

The hemispherical cup anemometer (still used today) was invented in 1846 by Irish researcher, John Thomas Romney Robinson and consisted of four hemispherical cups. The cups rotated horizontally with the wind and a combination of wheels recorded the number of revolutions in a given time. Want to build your own hemispherical cup anemometer

A sonic anemometer

A sonic anemometer determines instantaneous wind speed and direction (turbulence) by measuring how much sound waves traveling between a pair of transducers are sped up or slowed down by the effect of the wind. The sonic anemometer was invented by geologist Dr. Andreas Pflitsch in 1994.

Mechanical Anemometer

In 1450, the Italian art architect Leon Battista Alberti invented the first mechanical anemometer. This instrument consisted of a disk placed perpendicular to the wind. It would rotate by the force of the wind, and by the angle of inclination of the disk the wind force momentary showed itself. The same type of anemometer was later re-invented by Englishman Robert Hooke who is often mistakenly considered the inventor of the first anemometer. The Mayans were also building wind towers (anemometers) at the same time as Hooke. Another reference credits Wolfius as re-inventing the anemometer in 1709.

Wind velocity or speed is measured by a cup anemometer, an instrument with three or four small hollow metal hemispheres set so that they catch the wind and revolve about a vertical rod. An electrical device records the revolutions of the cups and calculates the wind velocity. The word anemometer comes from the Greek word for wind, "anemos."

barometerBarometer - Pronunciation: [b u rom´ u t u r] - a barometer is an instrument for measuring atmospheric pressure. Two common types are the aneroid barometer and the mercurial barometer (invented first). Evangelista Torricelli invented the first barometer, known as the "Torricelli's tube".

Evangelista Torricelli was born October 15, 1608, in Faenza, Italy and died October 22, 1647 in Florence, Italy. He was a physicist and mathematician. In 1641, Evangelista Torricelli moved to Florence to assist the astronomer Galileo.

Lucien Vidie - Aneroid Barometer

In 1843, the French scientist Lucien Vidie invented the aneroid barometer. A aneroid barometer "registers the change in the shape of an evacuated metal cell to measure variations on the atmospheric pressure." Aneriod means fluidless, no liquids are used, the metal cell is usually made of phosphor bronze or beryllium copper.

The BarometerIt was Galileo that suggested Evangelista Torricelli use mercury in his vacuum experiments. Torricelli filled a four-foot long glass tube with mercury and inverted the tube into a dish. Some of the mercury did not escape from the tube and Torricelli observed the vacuum that was created. Evangelista Torricelli became the first scientist to create a sustained vacuum and to discover the principle of a barometer. Torricelli realized that the variation of the height of the mercury from day to day was caused by changes in the atmospheric pressure. Torricelli built the first mercury barometer around 1644

hygrometerA hygrometer is an instrument used to measure the moisture content or the humidity of air or any gas.

A hygrometer is an instrument used to measure the moisture content or the humidity of air or any gas. The best known type of hygrometer is the "dry and wet-bulb psychrometer", best described as two mercury thermometers, one with a wetted base, one with a dry base. The water from the wet base evaporates and absorbs heat causing the thermometer reading to drop. Using a calculation table, the reading from the dry thermometer and the reading drop from the wet thermometer are used to determine the relative humidity.

Other kinds of hygrometers use human hair (blond) to determine moisture content. These are called mechanical hygrometers, based on the principle that organic substances ( human hair) contract and expand in response to the relative humidity. The contraction and expansion moves a needle guage. In 1783, Swiss physicist and geologist, Horace Bénédict de Saussure built the first hygrometer using a human hair to measure humidity.

Some hygrometers use the measurements of changes in electrical resistance, using a thin piece of lithium chloride or other semiconductor devices and measuring the resistance which is affected by humidity.Leonardo da Vinci built the first crude hygrometer in the 1400s. Francesco Folli invented a more practical hygrometer in 1664.

Robert Hooke invented the universal joint, the iris diaphragm, and an early prototype of the respirator; invented the anchor escapement and the balance spring, which made more accurate clocks possible, invented or improved meteorological instruments such as the barometer, anemometer, and hygrometer; and so on.

John Frederic DaniellIn 1820, British chemist and meteorologist, John Frederic invented a dew-point hygrometer, which came into widespread use. Daniel is best known for inventing the Daniell cell, an improvement over the voltaic cell used in the early history of battery development.

rain gaugeA rain gauge measures how much rain has fallen

One source has is that the son of King Sejong the Great, who reigned the Choson Dynasty from 1418 to 145, invented the first rain gauge. King Sejong sought ways to improve agricultural technology to provide his subjects with adequate food and clothing.

In improving agricultural technology, Sejong contributed to the sciences of astronomy and meteorology (weather). He invented a calendar for the Korean people and ordered the development of accurate clocks. Droughts plagued the kingdom and King Sejong directed every village to measure the amount of rainfall.

RainmakersBorn in Fort Scott, Kansas, in 1875, Hatfield claimed to have been "a student of meteorology" for 7 years, during which time he discovered that by sending a secret combination of chemicals into the air clouds could be produced in large enough quantities that rain was sure to follow. On March 15, 1950, New York City hired Dr Wallace E Howell as the city's official "rainmaker".

Thermometersthermometers measure temperature by using materials that hange in some way when they are heated or cooled. The first thermometers were called thermoscopes, and while several inventors invented a version of the thermoscope at the same time, Italian inventor Santorio Santorio was the first inventor to put a numerical scale on the instrument. In 1724, Gabriel Fahrenheit invented the first mercury thermometer.

The first thermometers were called thermoscopes and while several inventors invented a version of the thermoscope at the same time, Italian inventor Santorio Santorio was the first inventor to put a numerical scale on the instrument. Galileo Galilei invented a rudimentary water thermometer in 1593 which, for the first time, allowed temperature variations to be measured. In 1714, Gabriel Fahrenheit invented the first mercury thermometer, the modern thermometer.

Santorio invented several instruments, a wind gauge, a water current meter, the "pulsilogium," and a thermoscope, a precursor to the thermometer. Santorio was the first to apply a numerical scale to his thermoscope, which later evolved into the thermometer.