3S技术在水利工程中的应用-遥感(1).ppt

RemoteSensing遥感,RemoteSensing遥感,LastLectureDefinitionsofRemoteSensingHistoryofremotesensingTypesofaerialphotographPhotogrammetryParallaxConclusions,RemotesensinginvolvescollectinginationabouttheEarthfromadistanceusingelectromagneticsensorsItevolvedfromaerialphotographyVerticalstereopairsofaerialphotographsareusedtotake3-Dmeasurementsbymeasuringparallax,RemoteSensing遥感,SourcesofEnergy,SensingSystems,Theremotesensingprocess,Transmissionthroughatmospheredownintensityinverselyproportionalto4thpowerofwavelengthbluelightscatteredc.fourtimesasmuchasredlightandUVlightc.16timesasmuchasredlightCausesthebluecolorofthesky,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,AtmosphericwindowsAtmosphericmodificationofEMRincludesScattering（散射）Refraction（折射）Absorption（吸收）MIESCATTERINGTakesplaceinloweratmosphere0-5kmCausedbyaerosolsdust,pollen,smokeandwaterdropletsParticleshaveadiameterroughlyequaltotheincidentwavelengthWavelengthdependent;affectsEMRmostlyinthevisible,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,AtmosphericwindowsAtmosphericmodificationofEMRincludesScattering（散射）Refraction（折射）Absorption（吸收）NON-SELECTIVESCATTERINGTakesplaceinloweratmosphereParticlesmuchlargerthanincidentradiationNotwavelengthdependentPrimarycauseofhaze,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,AtmosphericwindowsAtmosphericmodificationofEMRincludesScattering（散射）Refraction（折射）Absorption（吸收）GENERALEFFECTSOFSCATTERINGSatelliteimagesincludeatmosphericpathradianceinadditiontosurfaceradianceDecreasesspatialdetailfuzzyimagesReducescontrast,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,AtmosphericwindowsAtmosphericmodificationofEMRincludesScattering（散射）Refraction（折射）Absorption（吸收）REFRACTIONBendingoflightOccurswhenlightpassesthroughtwomediawithdifferentdensityatmosphericlayersCausesmiragesduringhotdaysDegradessatelliteimagesonhot,humiddays,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,AtmosphericwindowsAtmosphericmodificationofEMRincludesScattering（散射）Refraction（折射）Absorption（吸收）ABSORPTIONMostlycausedbythreeatmosphericgasesOZONEabsorbsUVCARBONDIOXIDELoweratmosphere,absorbs13-17.5micronsWATERVAPOURLoweratmosphere,absorbsbetween5.5and7micronsandabove27microns.,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,Atmosphericwindows（大气窗口）Thisallmeansthatwecan’tusethewholerangeoftheEMRspectrumforremotesensingTheatmosphereisonlytransparentenoughatcertainwavelengthsevenherewelosec.20,,,,,,,,,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,Atmosphericwindows,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,Atmosphericwindows,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,StructureTheelectromagneticspectrumVisibleradiationWavelengthsshorterthanvisibleblueWavelengthslongerthanvisibleredAtmosphericwindowsSourcesofradiationusedinremotesensingConclusions,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,SourcesofradiationusedinremotesensingNaturalradiationPassiveReflectedsolarradiationEmittedterrestrialradiationcheapandeasyArtificialradiationActivemorecontrollablebutrequiresalotofpower,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,Naturalradiation,Stefan-Boltzmann’sLawMTsT4s5.6703x10-8W/m2K4RelatesradiancetothefourthpoweroftemperatureinK,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,Naturalradiation,PlanckRadiationLaw,Givesshapeofspectralcurve,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,,NaturalradiationWein’sDisplacementLawAstemperatureincreases,thepeakoftheradiationcurvemovestoshorterwavelengths,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,Naturalradiation,Wein’sDisplacementLawλmT2898μmKWhereλmwavelengthofspectralpeakTtemperatureK,,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,NaturalradiationBecausetheSunisalothotterthantheEarth,thetwosourcesofradiationproducedifferentspectralcurves,definedbyStefan-Boltzmann’s,Planck’sandWein’sLawsSunVisibletoSWIREarthThermaltomicrowaveSmalloverlaparound3microns,,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,Naturalradiation,Solar,Terrestrial,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,ArtificialradiationArtificialradiationisincreasinglyusedinremotesensingLasersvisibleradiationRadarmicrowaveradiation,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,StructureTheelectromagneticspectrumVisibleradiationWavelengthsshorterthanvisibleblueWavelengthslongerthanvisibleredAtmosphericwindowsSourcesofradiationusedinremotesensingConclusions,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,ConclusionsRemotesensingmakesuseofvisible-SWIRreflectedsolarradiation,thermalemittedterrestrialradiationandmicrowaveseitheremittedorartificiallyproducedWavelengthslimitedtoatmosphericwindows,ElectromagneticRadiationandtheElectromagneticSpectrum（电磁波与电磁波谱）,Thedatatransferchain1,,,,,,Solarradiation,Reflectionoffullspectrum,Transmissionthroughatmospheredownup,Detection4bandsSPOT,空间信息采集（包括遥感平台和传感器）地面接收和预处理（包括辐射校正和几何校正）地面实况调查（如收集环境和气象数据）信息分析应用系统,Theremotesensingprocess,