2nd Online Activity

1. History of Meteorology and Invention of Weather Instruments

2. Meteorology The word 'meteorology' was coined from a research book called 'Meteorologica' which was written by Aristotle, a Greek scientist and philosopher. This early work described the science of earth like its geology, elements, hydrology, seas, wind and weather. In the modern term, the term meteorology explains a complete science. It is for understanding the dynamics of atmosphere and forecasting weather phenomena like hurricanes and thunderstorms.

3. In Bible times the forecasting of weather conditions was based solely upon observations of the sky. This method of simple observation prevailed until 1643 when Italian physicist Evangelista Torricelli invented the barometer. This simple device was able to measure the pressure of the air. A device to measure temperature was invented by Galileo Galileiand the factor that atmospheric pressure was linked to altitude was discovered by Blaise Pascal. History of Meteorology

4. Atmospheric humidity was also able to be measured when the hygrometer was invented in 1644. Meteorology is a lot related with cycles and their analysis which was what Fernando II de Medici wanted to prove. He carried out a very determined program in 1654 for recording weather patterns in different European cities with a view to compile data and make their analysis. In 1714 German physicist Daniel Fahrenheit developed the mercury thermometer. It was now possible to accurately measure the weather. It was in 1765 that daily measurements of air pressure, moisture content, wind speed and direction began to be made. This was first done by French scientist Laurent Lavoisier who stated,“ With all of this information it is almost always possible to predict the weather one or two days ahead with reasonable accuracy."

5. In 1854 a French warship and 38 merchant vessels sank in a fierce storm off the Crimean port of Balaklava. In the mid 1800s there was still no quick way of transferring weather data from one location to the next. Often the weather that was being warned about would arrive before the data did. That was until Samuel Morse invented his electric telegraph to allow speedy transference of information. Morse's invention now made it possible for the Paris Observatory to begin publishing the first modern weather maps.

6. By 1872, Britain's Meteorological Office had followed suit. From then on the acquiring of weather data became more and more complex, as did the resulting meteorological maps. New graphic devices were developed to convey more information.Isobars, for example, were invented - lines drawn to link points that have the same barometric pressure. Isotherms connect locations that have the same temperature. Other graphic devices were also developed - symbols to show wind direction and force, as well as lines that depict the meeting of warm and cold air masses.

7. In the 20th century much sophisticated meteorological equipment has also been developed. Radiosondes these are instruments that can measure atmospheric conditions and then radio the information back to the station. In 1960 the world's first weather satellite, TIROS 1 was sent into space equipped with a TV camera. Today, weather satellites orbit the earth from pole to pole. Geostationary satellites stay in a fixed position above the earth and constantly monitor one part of the globe. The forecasting of the weather took a leap forward when, shortly after World War One, British meteorologist Lewis Richardson stated that since the atmosphere follows the laws of physics, it is possible to use mathematical calculations to predict future weather conditions.

8. The forecasting of the weather took a leap forward when, shortly after World War One, British meteorologist Lewis Richardson stated that since the atmosphere follows the laws of physics, it is possible to use mathematical calculations to predict future weather conditions. The atmosphere above each square is called a box and observations of atmospheric wind, air pressure, temperature and humidity are recorded at 20 different levels of altitude. A computer than analyzes the data received from the more than 3,500 observation stations around the world and produces a forecast of what the world's weather will be for the next 15 minutes. Then a forecast for the next 15 minutes is produced. Repeating this process a computer can produce a six day world forecast in just 15 minutes.

9. To achieve even greater accuracy the British Meteorological Office has what is called the Limited Area Model which covers just the North Atlantic and European sectors. It's grid points are spaced at intervals of just 50 kilometers. As an example, when air cooled by the North Sea moves over the European land mass, a thin cloud layer often forms. Whether this cloud layer means rain is on the way in continental Europe the next day or whether it simply evaporates in the sun's heat depends on a temperature difference of only a few tenths of a degree. It is up to the forecaster to predict which will be the case.

10. *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." Weather

11. Measuring the Weather 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. Invention of Weather Instrument

12. 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." Anemometer

13. Barometeris a scientific instrument used in meteorology to measure atmospheric pressure. It can measure the pressure exerted by the atmosphere by using water, air, or mercury. Pressure tendency can forecast short term changes in the weather. Numerous measurements of air pressure are used within surface weather analysis to help find surface troughs, high pressure systems, and frontal boundaries. Barometer

14. Thermometer(from the Greekθερμός (thermo) meaning "warm" and meter, "to measure") is a device that measures temperature or temperature gradient using a variety of different principles.[1] A thermometer has two important elements: the temperature sensor (e.g. the bulb on a mercury thermometer) in which some physical change occurs with temperature, plus some means of converting this physical change into a value (e.g. the scale on a mercury thermometer). Thermometers increasingly use electronic means to provide a digital display or input to a computer. Thermometer

15. A SLING PSYCHROMETER measures relative humidity, using the cooling effect of evaporation. Two thermometers are used in a sling psychrometer. Wet the cloth of one of the thermometers and swing the psychrometer around a few times. Water evaporates from the cloth, causing the temperatures on that thermometer to be lower the the other. Sling Psychrometer

16. A rain gauge (also known as a udometer or a pluviometer [Pluviograph ] or an ombrometer or a cup) is a type of instrument used by meteorologists and hydrologists to gather and measure the amount of liquid precipitation (solid precipitation is measured by a snow gauge) over a set period of time. Rain Gauge

17. A weather map displays various meteorological features across a particular area at a particular point in time. Maps using isotherms show temperature gradients,[2] which can help locate weather fronts. Isotach maps, analyzing lines of equal wind speed,[3] on a constant pressure surface of 300 mb or 250 mb show where the jet stream is located. Use of constant pressure charts at the 700 and 500 hPa level can indicate tropical cyclone motion. Two-dimensional streamlines based on wind speeds at various levels show areas of convergence and divergence in the wind field, which are helpful in determining the location of features within the wind pattern Weather Map

18. A Weather Vane is an instrument for showing the direction of the wind. They are typically used as an architectural ornament to the highest point of a building. Although partly functional, weather vanes are generally decorative, often featuring the traditional cockerel design with letters indicating the points of the compass. Other common motifs include ships, arrows and horses. Not all weather vanes have pointers. The word 'vane' comes from the Anglo-Saxon word 'fane' meaning 'flag'. Weather Vane

19. A compass is a navigational instrument for determining direction relative to the Earth's magnetic poles. It consists of a magnetized pointer (usually marked on the North end) free to align itself with Earth's magnetic field. Compass

20. The weather satellite is a type of satellite that is primarily used to monitor the weather and climate of the Earth. Satellites can be either polar orbiting, seeing the same swath of the Earth every 12 hours, or geostationary, hovering over the same spot on Earth by orbiting over the equator while moving at the speed of the Earth's rotation.[1] These meteorological satellites, however, see more than clouds and cloud systems. Weather Satellite

21. A Hygrometer is an instrument used for measuring the moisture content in the environmental air, or humidity. Humidity is difficult to measure accurately. Most measurement devices usually rely on measurements of some other quantity such as temperature, pressure, mass or a mechanical or electrical change in a substance as moisture is absorbed. From calculations based on physical principles, or especially by calibration with a reference standard, these measured quantities can lead to a measurement of humidity. Modern electronic devices use temperature of condensation, changes in electrical resistance, and changes in electrical capacitance to measure humidity changes. Hydrometer

22. A weather or sounding balloon is a balloon (specifically a type of high altitude balloon) which carries instruments aloft to send back information on atmospheric pressure, temperature, humidity and wind speed aloft by means of a small, expendable measuring device called a radiosonde Weatheror sounding balloon