In1820,GermanH.W.Brandesfilledthemapwiththeobservationrecordsofairpressureandwindatthesametimefromvariousplacesinthepast,anddrewtheworld'sfirstweathermap.In1851,BritishJ.GlescherexhibitedthefirstgroundweathermapdrawnbytelegraphtocollectmeteorologicaldatafromvariousplacesattheRoyalExposition.Hewasthepioneerofmoderngroundweathermaps.Inthe1930s,high-altitudeweathermapswereonlyavailableaftertheestablishmentofhigh-altitudeobservationnetworksintheworld.
InNovember1854,thefamousCrimeanWarinhistorywasgoingonfiercely.TheBritishandFrenchforcessurroundedSevastopol,andtheMarineswerepreparingtolandatBalaklavaPortintheBlackSea.Atthistime,theBlackSeasuddenlyhadastrongwindandhugewaves.TheAnglo-Frenchalliedforcescollapsedwithoutafight,andalmosttheentirearmywaswipedout.
AfterNapoleonIIIreceivedthemessage,heimmediatelyorderedtheParisObservatorytoinvestigatethecauseofthestorm,andthedirectoroftheParisObservatory,LeFryer,tookoverthisimportanttask.Hecollectedweatherreportsbeforeandafterthestormfrommeteorologistsfromallovertheworld.Afterthereportwascollected,hefilledouttheweatherconditionsinvariousplacesatthesametimeinsequence.Aftercarefulanalysis,hefoundthatthestormwasmovingfromnorthwesttosoutheast,whenitreachedtheBlackSea1to2daysbefore.,SpainandFrancehavebeenaffectedbyitfirst.
Afteranalysis,LeVrierbelievedthatiftherewereweatherstationsalongtheAtlanticOceaninEuropeatthattime,thestorminformationcouldbereportedtotheBritishandFrenchfleetsintime,andtheBritishandFrenchfleetswouldbeprotectedfromthestorm.LeVrière'sproposalhasreceivedresponsesfrommanycountries.In1856,Franceestablishedthefirstformalweatherservicesystem.SomeothercountriesinEurope,theUnitedStates,andJapanhavealsosuccessivelyorganizedtheconstructionofobservationnetworks,begantopublishtheweatherobservationresultsoftheday,drawweathermaps,andprovideservicesforobservingandforecastingweather.Theweathermapisthebeginningofmodernweatherforecasting.Itexpandstheweatherforecastfrompointtoareaandgraduallymatures.
Classification
Weathermapscanbesimplydividedintotwocategories:"ground"and"highaltitude"."Ground"actuallyreferstothesurfaceoftheearthingeneral.Differentlocations,suchasoceansorridges,canrepresentextremelydifferentheights.Therefore,whenreadinggroundweather,temperature,winddirectionandwindspeedgraphs,payattentiontothealtituderepresented.Ontheotherhand,inordertofacilitatethecomparisonofdifferentatmosphericpressuresystems,theatmosphericpressuremapusesthemeansealevelasthereferencealtitude.
Asfor"highaltitude",sinceconventionalhigh-altitudeobservationsandatmosphericanalysisareperformedonastandardisobaricsurface,high-altitudeweathermapsarealsousedtodrawonaconstantpressuresurface.Restrictedbythegravityoftheearth,thedensityandpressureoftheatmospherewilldecreaseasthealtitudeincreases.Therefore,inthestandardatmosphere,airpressureunitscanbeusedtoexpressaltitude.Thefollowingtablelistsfourcommonlyusedstandardisobarsandtheiraltitudes:
Airpressure | Approximatealtitude |
200hPa | 12,000meters |
500hPa | 5,600meters |
700hPa | 3,000meters |
850hPa | 1,500meters |
925hPa | 1,000meters |
Groundweathermap
Alsocalledgroundmap.Amapusedtoanalyzethegroundweathersystemandatmosphericconditionsatacertaintimeinalargearea.Atthecorrespondinglocationofaweatherstationinthisfigure,fillinthemeteorologicalelementobservationrecordsofthestationatacertaintimewithvaluesorsymbols.Themeteorologicalelementsfilledinare:temperature,dewpoint,winddirectionandwindspeed,sealevelpressureand3-hourpressuretendency,visibility,totalcloudcoverandlowcloudcover,cloudshapeofhighcloud,mediumcloudandlowcloud,lowcloudhigh,Currentweatherandweatherinthepast6hours,precipitationinthepast6hours,specialweatherphenomena(suchasthunderstorms,strongwinds,hail),etc.Drawisobarsbasedonthepressurevaluesofeachstation,analyzethedistributionofhighandlowpressuresystems;analyzeanddeterminethepositionsofvariousfrontsbasedontemperature,dewpoint,andweatherdistribution.Thiskindofweathermapcomprehensivelyshowsthelocationofweathersystemssuchasgroundfronts,cyclones,anticyclones,andweathersuchasthunderstorms,precipitation,fog,gales,andhailatacertaintimeandthescopeoftheirinfluence.
High-altitudeweathermap
Alsocalledhigh-altitudeisobaricmaporhigh-altitudemap.Diagramsusedtoanalyzehigh-altitudeweathersystemsandatmosphericconditions.Thealtitudemapofacertainpressuresurfaceisfilledwiththeobservationrecordsofgeopotentialheight,temperature,temperaturedewpointdifference,winddirectionandwindspeedofeachradiosondeorwindmeasuringstationonthepressuresurface.Analyzecontoursandisothermsbasedonthenumericalvaluesofrelevantelementsandlabelvariousweathersystems.Thecontourlinesontheisobargraphrepresentthespatialdistributionoftheisobaratacertainmoment,reflectingthelocationandrangeofinfluenceofweathersystemssuchashigh-altitudelow-pressuretroughs,high-pressureridges,cut-offlows,andblockedhighs.Low-pressuretroughisabbreviatedastrough.Itistheareawheretheairpressureislowerthantheadjacentthreesidesbuthigherthantheothersideatthesameheight.Thecontourlines(orisobars)ontheisobaricsurface(orcontour)areapproximatelyparallel.TheV-shaped,Λ-shapedlow-pressuregrooveisalsocalledaninvertedgroove.Inthelow-pressuretank,thelineofthepointswiththelargestcycloniccurvatureoftheisobarorcontourlineisthegroovelineofthetank.Thetroughlinedividesthelow-pressuretroughintotwoparts,onesideofthelow-pressuretrough'sadvancingdirectionis"beforethetrough",andtheothersideis"behindthetrough".Generally,thereisanupdraftinfrontofthetrough,whichiscloudyandrainy;thereisasinkingairbehindthetrough,whichismoresunnyandgood.High-pressureridgeisabbreviatedasridge.Itistheareawheretheairpressureishigherthantheadjacentthreesidesbutlowerthantheotherontheplanewiththesamealtitude.Thecontourlines(orisobars)ontheisobaricsurface(orcontoursurface)mapareapproximatelyparallel.The∩shape.Inthehigh-pressureridge,thejointlineofthepointswiththelargestanticycloniccurvatureoftheisobarorcontouristheridge.Isothermsrepresentthedistributionofwarmandcoldairontheisobaricsurface,andtheyareequaltothehighlinetocharacterizethedynamicandthermalpropertiesoftheweathersystem.Sometimesthereareconstantwindspeedlines,constanthumiditylines,constanttemperaturedewpointdifferencelines,etc.,whichreflectthespatialdistributionofrapidsandhumidity.Commonlyusedare850hPa,700hPa,500hPa,300hPa,200hPaand100hPaisobaricmaps.Theiraveragealtitudesareabout1500meters,3000meters,5500meters,and9000metersrespectively.,12,000metersand16,000meters.Thereisalsoahigh-altitudemapcalledathicknessmap,whichisusedtoanalyzethethicknessofthegaslayerbetweentwoisobaricsurfaces.Thisthicknessreflectstheaveragetemperatureofthegaslayer,wheretheatmosphereiswarmerinareaswiththickgaslayers,andviceversa.Athicknesschartof1000hPato500hPaiscommonlyused.Thisthicknessmapisoftensuperimposedonthe500hPaor700hPaisobaricmaptoshowthetemperaturedistributiononthe500hPaor700hPachart.
Auxiliarydiagrams
Therearethermodynamicdiagrams,profilediagrams,variablediagrams,etc.Thermodynamicchartisachartmadeaccordingtotheadiabaticequationofdryairandtheadiabaticequationofmoistair,alsocalledadiabaticchart.Thiskindofmapisgenerallyprintedwithisobars(ordinate),isotherms(abscissa),dryadiabaticlines(isopotentialtemperaturelines),wetadiabaticlines(equivalenttemperaturelines)andconstantsaturationratiohumiditylines.Fillinthepressure,temperature,andhumidityrecordsofacertainstationatvariousaltitudesonthemaptoanalyzetheatmosphericstabilityovertheweatherstationorcalculatevariousphysicalquantitiesthatcharacterizetheatmospherictemperatureandhumidity.
Theprofilediagramisadiagramusedtoanalyzetheverticaldistributionofmeteorologicalelementsandthedynamicandthermalstructureoftheatmosphere.Thechartisfilledwithrecordsoftemperature,humidity,andwinddirectionandwindspeedofvariousstandardisobaricsurfacesandcharacteristiclayers,andisobstructedwithisowindlines,isotherms,isothermallines,upperandlowerboundariesofthefrontalzone,etc.Itisdividedintotwotypes:spaceprofileandtimeprofile.Theformerusessimultaneoussoundingdatafrommultiplestationstoindicatethephysicalcharacteristicsoftheatmosphereonaverticalprofilealongacertaindirectionatacertaintime;thelatterusesmultipleconsecutivesoundingdatafromasinglestationtoindicatethattheatmosphericconditionsoverthestationwithinacertainperiodoftimevary.Theevolutionoftime.
Variablegraphsarealsocalledtrendgraphs,whichcanreflectthedistributionofchangesinameteorologicalelementinthepast12hoursor24hours.Commonlyusedarevariablepressure(high)graphandvariabletemperaturegraph.Thestrongandlarge-scalemeteorologicalelementvariableareahasacertainpredictivenessforthefuturetrendoftheelement.④Thesinglestationdiagramisasinglestationhigh-altitudewinddiagramdrawnwithpolarcoordinates,whichcanindicatethedynamicconditionsoftheverticalshearstrengthofthehigh-altitudewindnearthestationandthethermalconditionsofthecoldandwarmadvectionofeachlayer;therearealsogroundorhigh-altitudewinddiagrams.Agraphshowingchangesinelementsovertimeanddeviationsfromnormalconditions,etc.
Thebirthofweatherforecast
Thebirthofweatherforecastisrelatedtoawar.
InNovember1854,thefamousCrimeanWarinhistorywasgoingonfiercely.TheBritishandFrenchforcessurroundedSevastopol,andtheMarineswerepreparingtolandatBalaklavaPortintheBlackSea.Atthistime,theBlackSeasuddenlyhadastrongwindandhugewaves.TheAnglo-Frenchalliedforcescollapsedwithoutafight,andalmosttheentirearmywasdestroyed.
Accordingtotherequestofthemilitary,LeFryer,directoroftheParisObservatory,studiedthestorm.Hesentletterstometeorologistsfromvariouscountriestocollectweatherreportsbeforeandafterthestorm.Aftercollectingtheweatherreport,hefilledouttheweatherconditionsofvariousplacesatthesametimeonamapinturn.Linkingandanalyzingthemapsatdifferenttimes,hefoundthatthestormmovedfromwesttoeast,andithadalreadyaffectedSpainandFrance1to2daysbeforereachingtheBlackSea.
Afteranalysis,LevrierbelievedthatiftherewereweatherstationsinEuropeatthattime,thestormsituationcouldbereportedtotheBritishandFrenchfleetsintime,sothattheBritishandFrenchfleetscouldavoidthestorm.InMarch1855,hesuggestedtotheFrenchAcademyofSciencestoorganizeanobservationnetworktoquicklygatherobservationaldatainoneplace,analyzeanddrawweathermaps,anditispossibletoinferthecourseoffuturestorms.In1856,Franceestablishedtheworld'sfirstformalweatherforecastservicesystem.