Meteorological instruments are the equipment used to sample the state of the atmosphere at a given time. Each science has its own unique sets of laboratory equipment. Meteorology, however, is a science which does not use much lab equipment but relies more on on-site observation and remote sensing equipment. In science, an observation, or observable, is an abstract idea that can be measured and for which data can be taken. Rain was one of the first quantities to be measured historically. Two other measured weather-related variables are wind and humidity. Many attempts had been made prior to the 15th century to construct adequate equipment to measure atmospheric variables. Devices used to measure these three sprang up in the mid-15th century and were the rain gauge, the anemometer, the hygrometer; the 17th century saw the development of the barometer and the Galileo thermometer while the 18th century saw the development of the thermometer with the Fahrenheit and Celsius scales. The 20th century developed new remote sensing tools, such as weather radars, weather satellites and wind profilers, which provide better sampling both regionally and globally.
Remote sensing instruments collect data from weather events some distance from the instrument and stores the data where the instrument is located and transmits the data at defined intervals to central data centers. In 1441, king Sejong's 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, is known as the first anemometer. In 1607, Galileo Galilei constructs a thermoscope. In 1643, Evangelista Torricelli invents the mercury barometer. In 1662, Sir Christopher Wren invented the self-emptying, tipping bucket rain gauge. In 1714, Gabriel Fahrenheit creates a reliable scale for measuring temperature with a mercury-type thermometer. In 1742, Anders Celsius, a Swedish astronomer, proposed the'centigrade' temperature scale, the predecessor of the current Celsius scale. In 1783, the first hair hygrometer is demonstrated by Horace-Bénédict de Saussure.
In 1806, Francis Beaufort introduced his system for classifying wind speeds. The April 1960 launch of the first successful weather satellite, TIROS-1, marked the beginning of the age where weather information became available globally; this was used to measure the temperature of the surrounding air. A thermometer measures the kinetic energy of the molecules within air. A barometer measures atmospheric pressure, or the pressure exerted by the weight of the Earth's atmosphere above a particular location. An anemometer measures the wind speed and the direction the wind is blowing from at the site where it is mounted. A hygrometer measures the relative humidity at a location, which can be used to compute the dew point. Radiosondes directly measure most of these quantities, except for wind, determined by tracking the radiosonde signal with an antenna or theodolite. Supplementing the radiosondes a network of aircraft collection is organized by the World Meteorological Organization, which use these instruments to report weather conditions at their respective locations.
A sounding rocket or rocketsonde, sometimes called a research rocket, is an instrument-carrying rocket designed to take measurements and perform scientific experiments during its suborbital flight. A pyranometer is a type of actinometer used to measure broadband solar irradiance on a planar surface and is a sensor, designed to measure the solar radiation flux density from a field of view of 180 degrees. A ceilometer is a device that uses a laser or other light source to determine the height of a cloud base. Ceilometers can be used to measure the aerosol concentration within the atmosphere. A ceiling balloon is used by meteorologists to determine the height of the base of clouds above ground level during daylight hours; the principle behind the ceiling balloon is a balloon with a known ascent rate and determining how long the balloon rises until it disappears into the cloud. Ascent rate times ascent time yields the ceiling height. A disdrometer is an instrument used to measure the drop size distribution and velocity of falling hydrometeors.
Rain gauges are used to measure the precipitation. Remote sensing, as used in meteorology, is the concept of collecting data from remote weather events and subsequently producing weather information; each remote sensing instrument collects data about the atmosphere from a remote location and stores the data where the instrument is located. The most common types of remote sensing are radar and satellites; the main uses of radar are to collect information concerning the coverage and characteristics of precipitation and wind. Satellites are chiefly used to determine cloud cover, as well as wind. SODAR is a meteorological instrument as one form of wind profiler, which measures the scattering of sound waves by atmospheric turbulence. Sodar systems are used to measure wind speed at various heights above the ground, the thermodynamic structure of the lower layer of the atmosphere. Radar and lidar are not passive because both use electromagnetic radiation to illuminate a specific portion of the atmosphere.
Weather satellites along with more general-purpose Earth-observing satellites circling the earth at various altitudes have become an indispensable tool for studying a wide range of phenomena from forest fires to El Niño. A weather station is a facility with instruments and equipment to make observations of atmo
A thermometer is a device that measures temperature or a temperature gradient. A thermometer has two important elements: a temperature sensor in which some change occurs with a change in temperature. Thermometers are used in technology and industry to monitor processes, in meteorology, in medicine, in scientific research; some of the principles of the thermometer were known to Greek philosophers of two thousand years ago. The modern thermometer evolved from the thermoscope with the addition of a scale in the early 17th century and standardisation through the 17th and 18th centuries. While an individual thermometer is able to measure degrees of hotness, the readings on two thermometers cannot be compared unless they conform to an agreed scale. Today there is an absolute thermodynamic temperature scale. Internationally agreed temperature scales are designed to approximate this based on fixed points and interpolating thermometers; the most recent official temperature scale is the International Temperature Scale of 1990.
It extends from 0.65 K to 1,358 K. Various authors have credited the invention of the thermometer to Hero of Alexandria; the thermometer was not a single invention, but a development. Hero of Alexandria knew of the principle that certain substances, notably air and contract and described a demonstration in which a closed tube filled with air had its end in a container of water; the expansion and contraction of the air caused the position of the water/air interface to move along the tube. Such a mechanism was used to show the hotness and coldness of the air with a tube in which the water level is controlled by the expansion and contraction of the gas; these devices were developed by several European scientists in the 16th and 17th centuries, notably Galileo Galilei. As a result, devices were shown to produce this effect reliably, the term thermoscope was adopted because it reflected the changes in sensible heat; the difference between a thermoscope and a thermometer is. Though Galileo is said to be the inventor of the thermometer, what he produced were thermoscopes.
The first clear diagram of a thermoscope was published in 1617 by Giuseppe Biancani: the first showing a scale and thus constituting a thermometer was by Robert Fludd in 1638. This was a vertical tube, closed by a bulb of air at the top, with the lower end opening into a vessel of water; the water level in the tube is controlled by the expansion and contraction of the air, so it is what we would now call an air thermometer. The first person to put a scale on a thermoscope is variously said to be Francesco Sagredo or Santorio Santorio in about 1611 to 1613; the word thermometer first appeared in 1624 in La Récréation Mathématique by J. Leurechon, who describes one with a scale of 8 degrees; the word comes from the Greek words θερμός, meaning "hot" and μέτρον, meaning "measure". The above instruments suffered from the disadvantage that they were barometers, i.e. sensitive to air pressure. In 1629, Joseph Solomon Delmedigo, a student of Galileo, published what is the first description and illustration of a sealed liquid-in-glass thermometer.
It is described as having a bulb at the bottom of a sealed tube filled with brandy. The tube has a numbered scale. Delmedigo does not claim to have invented this instrument, nor does he name anyone else as its inventor. In about 1654 Ferdinando II de' Medici, Grand Duke of Tuscany produced such an instrument, the first modern-style thermometer, dependent on the expansion of a liquid, independent of air pressure. Many other scientists experimented with various designs of thermometer. However, each inventor and each thermometer was unique—there was no standard scale. In 1665 Christiaan Huygens suggested using the melting and boiling points of water as standards, in 1694 Carlo Renaldini proposed using them as fixed points on a universal scale. In 1701, Isaac Newton proposed a scale of 12 degrees between the melting point of ice and body temperature. In 1714 Dutch scientist and inventor Daniel Gabriel Fahrenheit invented the first reliable thermometer, using mercury instead of alcohol and water mixtures.
In 1724 he proposed a temperature scale. He could do this because he manufactured thermometers, using mercury for the first time and the quality of his production could provide a finer scale and greater reproducibility, leading to its general adoption. In 1742, Anders Celsius proposed a scale with zero at the boiling point and 100 degrees at the freezing point of water, though the scale which now bears his name has them the other way around. French entomologist René Antoine Ferchault de Réaumur invented an alcohol thermometer and temperature scale in 1730 that proved to be less reliable than Fahrenheit's mercury thermometer; the first physician that put thermometer measurements to clinical practice was Herman Boerhaave. In 1866, Sir Thomas Clifford Allbutt invented a clinical thermometer that produced a body temperature reading in five minutes as opposed to twenty. In 1999, Dr. Francesco Pompei of the Exergen Corporation introduced the world's first temporal artery thermometer, a non-
A ceiling balloon called a pilot balloon or pibal, is used by meteorologists to determine the height of the base of clouds above ground level during daylight hours. In the past, sometimes today, a theodolite was used to track the balloon in order to determine the speed and direction of winds aloft; the principle behind the ceiling balloon is that timing of a balloon with a known ascent rate from its release until it disappears into the clouds can be used to calculate the height of the bottom of the clouds. A ceiling balloon is a small red, rubber balloon measuring 76 mm across prior to inflation, inflated to ~40 cm diameter. After inflation the balloon is released. By timing the balloon from release until it enters the cloud a ceiling height can be obtained; when inflated the balloon will rise at rate of 140 m/min. The bases of clouds are rarely flat and solid, so the ceiling height is not when the balloon disappears but when the colour begins to fade; the balloon can be used to measure the vertical visibility into a layer of fog or blowing snow.
In this case the balloon will begin to fade as soon as it is released, so the vertical visibility is when the balloon disappears. If the balloon is visible for a considerable distance into the cloud layer the observer should make note of it as it is of importance to aircraft; the ceiling balloon is a reliable and simple way to get an indication of the height of clouds. However, it does suffer from some disadvantages. Rain and wet snow may slow the ascent of the balloon, giving a falsely high ceiling and high winds and poor visibility may cause the balloon to appear to enter the cloud before it does; as the balloon rises at a rate of 140 m/min it will take over five minutes for the balloon to reach 700 m. Beyond this height the ability to follow the balloon with binoculars, is poor, as the slightest movement of the eye off the balloon will certainly ensure that it vanishes. At night when it is not practical to use a balloon the ceiling projector is used. However, during twilight it may be impossible to use the ceiling projector and a pibal light may be used.
This is a simple flashlight bulb attached to a battery. To charge the battery it is immersed in water for three minutes and tied to the balloon prior to inflation; these are used today. The balloons and associated equipment are stored in a cabinet mounted on a wall close to the gas cylinders; the cabinet has three doors one of which opens down and to it the filler stand is attached. At the top of the filler stand is a "L" shaped pipe with two rings, a small one on the bottom and a larger one on the top called the inflation nozzle; the rings stop the tube from dropping through the stand or rising too far when the balloon is inflated. The top ring has several grooves cut into it, to help grip the balloon, fitted to it. At the bottom of the pipe is a weight that, when the precise amount of gas has been added, will lift to indicate the balloon is full. A rubber hose passes through the filler stand twice; the first hole is larger than the tube to permit movement, while the second is used to hold the tubing in place.
From there the tube runs to a needle valve. A second tube will run from the valve to a regulator valve, attached to the gas cylinder; this valve has two pressure gauges attached. One showing the total pressure remaining in the gas cylinder and the second showing the amount of gas flowing through the tubing; the cylinder, made of steel and weighs about 140 lb. It contains the equivalent of about 200 ft³ of gas at standard pressure, stored at a pressure of 2000 psi and will inflate 120 balloons. On the opposite side of the cabinet is space to store balloons and pibal lights; the gas used to fill the balloon is hydrogen. Because of its low cost ceiling balloons are filled with hydrogen gas, but sometimes helium is used; the balloon is attached to the inflation nozzle and a piece of string is wound around the neck. After donning safety glasses and hearing protection a check is made to ensure the needle valve is closed; the main valve on the cylinder is opened, followed by the regulator valve. Next, the needle valve is opened and the balloon begins to inflate.
As the balloon reaches the correct size the inflation nozzle will begin to lift. At this point the needle valve is closed along with the regulator cylinder vale; the string is used to tie off the balloon neck to ensure that no gas can escape. Caution must be used during inflation due to its failure. If the person inflating the balloon is not wearing goggles or hearing protectors eye or ear damage can result. Weather balloon Observation balloon Timeline of hydrogen technologies Theodolite#Pibal Environment Canada - Atmospheric Environment Services, Technical Manual Ceiling Balloon Equipment 76 mm
The ceiling projector or cloud searchlight is used to measure the height of the base of clouds above the ground. It is used in conjunction with an alidade positioned 1000 ft away and wherever possible set at the same level; the projector is set at 90°, although 71° 31' may be used, in relation to the terrain. The projector consists of a 430 W incandescent bulb set in a weatherproof housing. Inside the housing are two mirrors. Both mirrors are focused to produce a high intensity beam of light that renders a visible spot on the base of the cloud; the alidade is mounted on a post at a height of 5 ft from the ground. It consists of an arm with a open sight at one end and a rubber eyepiece at the other; the arm is mounted onto a curved scale, marked both in meters and the coded cloud height. The observer looks through the eyepiece and sets the sight onto the spot projected on the cloud and reads the height from the attached scale; when the cloud is thin the beam of light may penetrate into the cloud.
The observer should read the scale. However, a remark may be made as to how far into the cloud the light was able to penetrate as this may be useful. In the case of fog or blizzard conditions the observer should read the scale where the beam disappears. Ceilometer Trigonometric function Triangle Department of Transport - Meteorological Branch - Ceiling Projectors and Associated Equipment - Manual 70
Climatology or climate science is the scientific study of climate, scientifically defined as weather conditions averaged over a period of time. This modern field of study is regarded as a branch of the atmospheric sciences and a subfield of physical geography, one of the Earth sciences. Climatology now includes aspects of biogeochemistry. Basic knowledge of climate can be used within shorter term weather forecasting using analog techniques such as the El Niño–Southern Oscillation, the Madden–Julian oscillation, the North Atlantic oscillation, the Northern Annular Mode, known as the Arctic oscillation, the Northern Pacific Index, the Pacific decadal oscillation, the Interdecadal Pacific Oscillation. Climate models are used for a variety of purposes from study of the dynamics of the weather and climate system to projections of future climate. Weather is known as the condition of the atmosphere over a period of time, while climate has to do with the atmospheric condition over an extended to indefinite period of time.
Chinese scientist Shen Kuo inferred that climates shifted over an enormous span of time, after observing petrified bamboos found underground near Yanzhou, a dry-climate area unsuitable for the growth of bamboo. Early climate researchers include Edmund Halley, who published a map of the trade winds in 1686 after a voyage to the southern hemisphere. Benjamin Franklin first mapped the course of the Gulf Stream for use in sending mail from the United States to Europe. Francis Galton invented the term anticyclone. Helmut Landsberg fostered the use of statistical analysis in climatology, which led to its evolution into a physical science; the Greeks began the formal study of climate. The first distinct climate treaties were the works of Hippocrates, who wrote Airs and Places in 400 B. C. E. Climatology is approached in various ways such as Paleoclimatology, which seeks to reconstruct past climates by examining records such as ice cores and tree rings. Paleotempestology uses these same records to help determine hurricane frequency over millennia.
The study of contemporary climates incorporates meteorological data accumulated over many years, such as records of rainfall and atmospheric composition. Knowledge of the atmosphere and its dynamics is embodied in models, either statistical or mathematical, which help by integrating different observations and testing how they fit together. Modeling is used for understanding past and potential future climates. Historical climatology is the study of climate as related to human history and thus focuses only on the last few thousand years. Climate research is made difficult by the large scale, long time periods, complex processes which govern climate. Climate is governed by physical laws; these equations are coupled and nonlinear, so that approximate solutions are obtained by using numerical methods to create global climate models. Climate is sometimes modeled as a stochastic process but this is accepted as an approximation to processes that are otherwise too complicated to analyze. Scientists use climate indices based on several climate patterns in their attempt to characterize and understand the various climate mechanisms that culminate in our daily weather.
Much in the way the Dow Jones Industrial Average, based on the stock prices of 30 companies, is used to represent the fluctuations in the stock market as a whole, climate indices are used to represent the essential elements of climate. Climate indices are devised with the twin objectives of simplicity and completeness, each index represents the status and timing of the climate factor it represents. By their nature, indices are simple, combine many details into a generalized, overall description of the atmosphere or ocean which can be used to characterize the factors which impact the global climate system. El Niño–Southern Oscillation is a global coupled ocean-atmosphere phenomenon; the Pacific Ocean signatures, El Niño and La Niña are important temperature fluctuations in surface waters of the tropical Eastern Pacific Ocean. The name El Niño, from the Spanish for "the little boy", refers to the Christ child, because the phenomenon is noticed around Christmas time in the Pacific Ocean off the west coast of South America.
La Niña means "the little girl". Their effect on climate in the subtropics and the tropics are profound; the atmospheric signature, the Southern Oscillation reflects the monthly or seasonal fluctuations in the air pressure difference between Tahiti and Darwin. The most recent occurrence of El Niño started in September 2006 and lasted until early 2007. ENSO is a set of interacting parts of a single global system of coupled ocean-atmosphere climate fluctuations that come about as a consequence of oceanic and atmospheric circulation. ENSO is the most prominent known source of inter-annual variability in weather and climate around the world; the cycle occurs every two to seven years, with El Niño lasting nine months to two years within the longer term cycle, though not all areas globally are affected. ENSO has signatures in the Pacific and Indian Oceans. In the Pacific, during major warm events, El Niño warming extends over much of the tropical Pacific and becomes linked to the SO intensity. While ENSO events are in phase between the Pacific and Indian Ocean
A radiometer or roentgenometer is a device for measuring the radiant flux of electromagnetic radiation. A radiometer is an infrared radiation detector or an ultraviolet detector. Microwave radiometers operate in the microwave wavelengths. While the term radiometer can refer to any device that measures electromagnetic radiation, the term is used to refer to a Crookes radiometer, a device invented in 1873 in which a rotor in a partial vacuum spins when exposed to light. A common belief is that the momentum of the absorbed light on the black faces makes the radiometer operate. If this were true however, the radiometer would spin away from the non-black faces, since the photons bouncing off those faces impart more momentum than the photons absorbed on the black faces. Photons do exert radiation pressure on the faces; the accepted explanation depends on having just the right degree of vacuum, relates to the transfer of heat rather than the direct effect of photons. A Nichols radiometer does demonstrate photon pressure.
It is much more sensitive than the Crookes radiometer and it operates in a complete vacuum, whereas operation of the Crookes radiometer requires an imperfect vacuum. The MEMS radiometer, invented by Patrick Jankowiak, can operate on the principles of Nichols or Crookes and can operate over a wide spectrum of wavelength and particle energy levels. Radiation pressure Net radiometer Bolometer Pyranometer Radiometry Spectroradiometer Copernicus Solar sail Photon rocket Active cavity radiometer https://www.youtube.com/watch?v=teEhoUB-FQE&list=UUXrJjdDeqLgGjJbP1sMnH8A Short video pertinent to the topic
A weather vane, wind vane, or weathercock is an instrument for showing the direction of the wind. It is used as an architectural ornament to the highest point of a building; the word vane comes from the Old English word fana meaning "flag". Although functional, weather vanes are decorative featuring the traditional cockerel design with letters indicating the points of the compass. Other common motifs include ships and horses. Not all weather vanes have pointers; when the wind is sufficiently strong, the head of the arrow or cockerel will indicate the direction from which the wind is blowing. The weather vane was independently invented in ancient China and Greece around the same time during the 2nd century BCE; the earliest written reference to a weather vane appears in the Huainanzi, a weather vane was fitted on top of the Tower of the Winds in Athens. The oldest textual reference to a weather vane comes from the Chinese Huainanzi dating from around 139 BC, which describes a "wind-observing fan".
The Tower of the Winds on the ancient Greek agora in Athens once bore on its roof a wind vane in the form of a bronze Triton holding a rod in his outstretched hand, rotating as the wind changed direction. Below this was a frieze adorned with the eight Greek wind deities; the eight-metre-high structure featured sundials, a water clock inside. It dates from around 50 BC. Military documents from the Three Kingdoms period of China refer to the weather vane as "five ounces", named after the weight of its materials. By the 3rd century, Chinese weather vanes were shaped like birds and took the name of "wind-indicating bird"; the Sanfu huangtu, a 3rd-century book written by Miao Changyan about the palaces at Chang'an, describes a bird-shaped wind vane situated on a tower roof, also an anemometer: The Han'Ling Tai' was eight li north-west of Chang'an. It was called'Ling Tai' because it was intended for observations of the Yin and the Yang and the changes occurring in the celestial bodies, but in the Han it began to be called Qing Tai.
Guo Yuansheng, in his Shu Zheng Ji, says that south of the palaces there was a Ling Tai, fifteen ren high, upon the top of, the armillary sphere made by Zhang Heng. There was a wind-indicating bronze bird, moved by the wind. There was a bronze gnomon 8 feet high, with a 13 feet long and 1 foot 2 inches broad. According to an inscription, this was set up in the 4th year of the Taichu reign-period; the oldest surviving weather vane with the shape of a rooster is the Gallo di Ramperto, made in 820 AD and now preserved in the Museo di Santa Giulia in Brescia, Lombardy. Pope Leo IV had a cock placed on the Old St. Peter's old Constantinian basilica. Pope Gregory I said that the cock "was the most suitable emblem of Christianity", being "the emblem of St Peter", a reference to Luke 22:34 in which Jesus predicts that Peter will deny him three times before the rooster crows; as a result of this, the cock began to be used as a weather vane on church steeples, in the 9th century Pope Nicholas I ordered the figure to be placed on every church steeple.
The Bayeux Tapestry of the 1070s depicts a man installing a cock on Westminster Abbey. One alternative theory about the origin of weathercocks on church steeples is that it was an emblem of the vigilance of the clergy calling the people to prayer. Another theory says that the cock was not a Christian symbol but an emblem of the sun derived from the Goths. A few churches used weather vanes in the shape of the emblems of their patron saints; the City of London has two surviving examples. The weather vane of St Peter upon Cornhill is not a key. Early weather vanes had ornamental pointers, but modern wind vanes are simple arrows that dispense with the directionals because the instrument is connected to a remote reading station. An early example of this was installed in the Royal Navy's Admiralty building in London – the vane on the roof was mechanically linked to a large dial in the boardroom so senior officers were always aware of the wind direction when they met. Modern aerovanes combine the directional vane with an anemometer.
Co-locating both instruments provides a coordinated readout. According to the Guinness World Records, the world's largest weather vane is a Tío Pepe sherry advertisement located in Jerez, Spain; the city of Montague, Michigan claims to have the largest standard-design weather vane, being a ship and arrow which measures 48 feet tall, with an arrow 26 feet long. A challenger for the title of world's largest weather vane is located in Yukon; the weather vane is a retired Douglas DC-3 CF-CPY atop a swiveling support. Located at the Yukon Transportation Museum beside Whitehorse International Airport, the weather vane is used by pilots to determine wind direction, used as a landmark by tourists and enjoyed by locals; the weather vane only requires a 5 knot wind to rotate. A challenger for the worlds tallest weather vane is located in Alberta; the classic weather vane that reaches to 50 feet is topped by a 1942 Case Model D Tractor. This landmark is located at the Canadian Tractor Museum; the term "weathervane" is a slang word for a politician who has frequent changes of opinion.
The National Assembly of Quebec has banned use of this slang term as a sl