Meteorology

Meteorology isstudy ofatmosphere that focuses on weather processesforecasting. Meteorological phenomenaobservable weather events which illuminate andexplained bysciencemeteorology. Those eventsbound byvariables that existEarth's atmosphere. Theytemperature, pressure, water vapor, andgradientsinteractionseach variable,howchangetime. The majorityEarth's observed weatherlocated introposphere.

Meteorology, climatology,atmospheric physicssubsets ofatmospheric sciences.

Tablecontents

1 Historymeteorology
2 Meteorologyclimatology: Some challengesthis century

2.1 Possibilitiesfuture improvements

3 Meteorological topicsphenomena
4 Meteorological InstrumentationEquipment
5 InstitutionsMeteorology/Atmospheric Science
6 Weather Related Links

Historymeteorology

Also refer totimelinemeteorology

The term meteorology goes back tobook Meteorologica (about 340 BC) by Aristotle, who combined observationsspeculation as toorigincelestial phenomena. The Greek word meteoron refersthings "high insky", thatbetween Earth andrealm ofstars, while logos means "study". A similar work, called "BookSigns", was published by Theophrastus,pupilAristotle. It was centered more on predictingweather by interpreting established celestial phenomena, such ashalo aroundmoon, without askingexplanations.

Further progress inmeteorological field hadwait until accurate instruments were available. Galileo constructedthermometer in1500s, followed by Torricelli's invention ofbarometer 1643. The dependenceatmospheric pressure on height was first shown by Blaise Pascal René Descartes. The anemometermeasuring wind speed was constructed1667 by Robert Hooke, while Horace de Saussure completed this list ofmost important meteorological instruments1780 withhair hygrometer, which measures humidity.

Other advances thatusually thoughtas part ofprogressionphysics were Robert Boyle's investigation ofdependencegas volume on pressure which leadthermodynamics Benjamin Franklin's kite experimentslightning.

The first essentially correct explanationglobal circulation was1735 study by George Hadley ofTrade Winds, which gave risecallingtropical cellzonal mean atmospheric circulation "Hadley cell". In 1835, Gaspard de Coriolis recognized thatrotationEarth causesvelocity-dependent force on bodies inreference frame ofnonrotating Earth.

Synoptic weather observations were still hindered bydifficultyestablishing certain weather characteristics such as clouds or wind. These were solved when Luke HowardFrancis Beaufort introduced their systemsclassifying clouds (1803)wind speeds (1806), respectively. The real turning point however wasinvention oftelegraph 1843 that allowed exchangeweather informationunprecedented speed.

Early in20th century, theoretical studiesatmospheric phenomena usually were performed analytically, thatby takingfluid-dynamical equations that govern atmospheric flow, simplifying them by neglecting lesser terms,lookingsolutionsthese equations. For example, Vilhelm Bjerknes developedmodel that explainsgeneration, intensificationultimate decay (the lifecycle)midlatitude cyclones, introducingideafronts, that is, sharply defined boundaries between air masses.

Starting in1950s, numerical experimentscomputers became feasible. The first weather forecasts derived this way used barotropic (that means, single-vertical-level) models,could successfully predictlarge-scale movementmidlatitude Rossby waves, that is,patternatmospheric lowshighs.

In1960s,chaotic nature ofatmosphere was first understood by Edward Lorenz, foundingfieldchaos theory. The mathematical advances achieved here later filtered backmeteorologymadepossibledescribelimitspredictability inherentatmospheric modelling. Thisknown as butterfly effect, becausegrowthdisturbances over time means that even one as minute asflapping ofbutterfly's wings could much later causelarge disturbanceform somewhere else.

In 1960,launchTiros 1,first weather satellite markedbeginning ofage where weather informationavailabe globally. Weather satellites alongmore general-purpose Earth-observing satellites circlingearth at various altitudes have become an indispensable toolstudyingwide rangephenomena from forest firesEl Niño.

In recent years, climate models have been developed that featureresolution comparableolder weather prediction models. These climate modelsusedinvestigate long-term climate shifts, such as what effects might be caused by human emissiongreenhouse gases.

Meteorologyclimatology: Some challengesthis century

Withdevelopmentpowerful new supercomputers likeEarth Simulator Japan, numerical modeling ofatmosphere can reach unprecedented accuracy. Thisnot only due toenhanced spatialtemporal resolution ofgrids employed, but also because these more powerful machines can modelEarth as an integrated climate system, where atmosphere, ocean, vegetation,man-made influences depend on each other realistically. The goalglobal meteorological modeling can thus currently be termed Earth System Modeling, withgrowing numbermodelsvarious processes coupledeach other. Predictionsglobal effects like Global Warming El Niñoexpectedbenefit substantially from these advancements.

Regional modelsalso becoming more interesting asresolutionglobal models increaseswithobserved increaseregional weather disasters such asElbe flooding2002 andEuropean heat wave2003. Decision makers expect from these models accurate assessments aboutpossible increasethese natural hazardsspecific regionscountermeasures (such as dikes or areas thatintentionally floodeddecreaseflooding somewhere else) that might be effectivepreventing or at least attenuating them.

For models at all scales, increased model resolution means less reliance on parameterizations , whichempirically derived expressionsprocesses that cannot be resolved onmodel grid. For example,mesoscale models individual clouds can now be resolved, removingneedformulations that average overgrid box. In global modeling, atmospheric waves such as gravity wavesshort temporalspatial scales can be represented without resortingoften overly simplified parameterizations.

Possibilitiesfuture improvements

With model output approaching observational data (e.g. from satellite soundings)resolution,sheer size ofdatasets means that data miningdata management will become equally important considerationsmeteorological computing. In light ofdecreasedensitysurfacerawinsonde observations, new algorithms havebe developedextract similarly accurate information from satellite data,example about cloud typedistribution. Data management will become more globalnature,some central archives storinglarge numbernumerical experiments from various institutions. This data needshavesufficient amountmetadata attachedcan then be conveniently retrieved byWWW interface from anywhere. These new archives will alleviateimportant taskcomparing experiments conducteddifferent models, whichinstrumentaltheir further improvement. Also, grid computing may be an interesting wayharnesspowermeteorological supercomputers more effectively. Of course international cooperationnothing unusualmodeling, but grid computing might automateprocessrunningmodel whereright amountcomputing resourcescurrently availableleave scientists more timeanalyzingresults.

Meteorological instrumentation thatused atsurface orairplanes also has roomimprovement. radarlidar show precipitation clouds by their effects on emitted monospectral electromagnetic waves. If radar measurements can be usedaccurately determineamountprecipitation (which asnowonly possiblerain gauges), this would be beneficialnumerical weather prediction. Lidar can be usedstudy clouds thatso thin thatcannot be seen bynaked eye such as certain typescirrus filaments. Researchers continuefind new atmospheric details such as high-altitude clouds that can form from contrails, which suggest that air travel may affect regional weather.

Aside from weatherclimate prediction, weather modification has been (often covertly) attempted since1950s---often bymilitary, but also at airports. But even without considerationanecdotal evidencetryinguse weather modification as"weapon" (such assupposed cloud seeding by US troops duringVietnam conflict), itclear that unilateral weather modification may leadpolitical tensions. Especially inMiddle East,possibilitywars about water supply loomsthis century (Hussein's Iraq used surface engineeringblock water from enteringland ofMarsh Arabs[1]). While many ofproposed systemsmodification ofwater cycle belong more todomainengineering thanmeteorology, itclear that meteorology has taken on additional political dimensions such asIPCC climate change mitigation proposals, andUNFCCC pollution control limitsclimate support payments from industrialized countriesdeveloping countries.

Finally, meteorologists must educatepublic more about weatherclimategeneral. Scientifically accurateunderstandable information about topics likeozone layer, climate change,effectsdeforestation, or sea level rise must be disseminatedmisinformation by special-interest groups be countered. ParticularlyEurope, which may see an increaseextreme weather events asalready has in1990s,population must be educatedpay closer attentionsevere weather warnings or information about other detrimental health factors such as high tropospheric ozone concentration or high levelsUV radiation. Similarly,better infrastructuredealnatural disasters must be developed akinsimilar services inUS. Political decision makers should rely on scientific assessmentproperly prepareweather eventsclimate effects.