METEOROLOGY<br />Meteorology is the interdisciplinary scientific study of the atmosphere that focuses on weather processes and short term forecasting (in contrast with climatology). Studies in the field stretch back millennia, though significant progress in meteorology did not occur until the eighteenth century. The nineteenth century saw breakthroughs occur after observing networks developed across several countries. Breakthroughs in weather forecasting were achieved in the latter half of the twentieth century, after the development of the computer.<br />
The word "meteorology" is from Greek μετέωρος, metéōros, "high in the sky"; and-λογία, -logia<br />
Research of visual atmospheric phenomena<br />In 1021, Ibn al-Haytham (Alhazen) wrote on the atmospheric refraction of light. He showed that the twilight is due to atmospheric refraction and only begins when the Sun is 19 degrees below the horizon, and uses a complex geometric demonstration to measure the height of the Earth's atmosphere as 52,000 passuum (49 miles (79 km)),which is very close to the modern measurement of 50 miles (80 km). He also realized that the atmosphere also reflects light, from his observations of the sky brightening even before the Sun rises.<br />
Instruments and classification scales<br />In 1441, King Sejongs son, Prince Munjong, invented the first standardized rain gauge. These were sent throughout the Joseon Dynasty of Korea as an official tool to assess land taxes based upon a farmer's potential harvest. In 1450, Leone Battista Alberti developed a swinging-plate anemometer, and is known as the first anemometer. In 1607, Galileo Galilei constructs a thermoscope. In 1611, Johannes Kepler writes the first scientific treatise on snow crystals: "StrenaSeu de NiveSexangula (A New Year's Gift of Hexagonal Snow)".<br />
Atmospheric composition research<br />In 1648, Blaise Pascal rediscovers that atmospheric pressure decreases with height, and deduces that there is a vacuum above the atmosphere.In 1738, Daniel Bernoulli publishes Hydrodynamics, initiating the kinetic theory of gases and established the basic laws for the theory of gases. In 1761, Joseph Black discovers that ice absorbs heat without changing its temperature when melting. In 1772, Black's student Daniel Rutherford discovers nitrogen, which he calls phlogisticated air, and together they developed the phlogiston theory. In 1777, Antoine Lavoisier discovers oxygen and develops an explanation for combustion.<br />
Research into cyclones and air flow<br />In 1494, Christopher Columbus experiences a tropical cyclone, leads to the first written European account of a hurricane. In 1686, Edmund Halley presents a systematic study of the trade winds and monsoons and identifies solar heating as the cause of atmospheric motions. In 1735, an ideal explanation of global circulation through study of the Trade winds was written by George Hadley.<br />
Observation networks and weather forecasting<br />In 1654, Ferdinando II de Medici establishes the first weather observing network, that consisted of meteorological stations in Florence, Cutigliano, Vallombrosa, Bologna, Parma, Milan, Innsbruck, Osnabrück, Paris and Warsaw. Collected data was centrally sent to Florence at regular time intervals. In 1832, an electromagnetic telegraph was created by Baron Schilling. The arrival of the electrical telegraph in 1837 afforded, for the first time, a practical method for quickly gathering surface weather observations from a wide area.<br />
Numerical weather prediction<br />In 1904, Norwegian scientist VilhelmBjerknes first argued in his paper Weather Forecasting as a Problem in Mechanics and Physics that it should be possible to forecast weather from calculations based upon natural laws.<br />It was not until later in the 20th century that advances in the understanding of atmospheric physics led to the foundation of modern numerical weather prediction. In 1922, Lewis Fry Richardson published "Weather Prediction By Numerical Process", after finding notes and derivations he worked on as an ambulance driver in World War I. <br />
METEOROLOGIST<br />Meteorologists are scientists who study meteorology. Meteorologists work in government agencies, private consulting and research services, industrial enterprises, utilities, radio and television stations, and in education. In the United States, meteorologists held about 9,400 jobs in 2009.<br />Meteorologists are best-known for forecasting the weather. Many radio and television weather forecasters are professional meteorologists, while others are merely reporters with no formal meteorological training. The American Meteorological Society and National Weather Association issue "Seals of Approval" to weather broadcasters who meet certain requirements.<br />
Measuring the Weather<br />In the early days of the Weather Bureau numerous clever mechanical devices were invented to measure and record any and every meteorological (weather) parameter conceivable: ombroscope or rainfall recorder, mechanical anemometer or wind speed indicator, remote readout wind vane, pole star recorder.<br />
Anemometer<br />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."<br />
Hygrometer<br />A hygrometer is an instrument<br />used to measure the moisture<br />content or the humidity of air or<br />any gas.<br />
Rain Gauge<br />A rain gauge measures how much rain has fallen.<br />
Thermometer<br />Thermometers measure temperature by using materials that change 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 SantorioSantorio was the first inventor to put a numerical scale on the instrument. In 1724, Gabriel Fahrenheit invented the first mercury thermometer.<br />
A particular slide catching your eye?
Clipping is a handy way to collect important slides you want to go back to later.