简介:IntermsofERBEandISCCPdata.andmeasured/calculatedsurfacenetradiation,computationisperformedoftheclimaticcharacteristicsofANR(atmosphericnetradiation)acrossChinaalongsidewiththediscussionandrelationstoothertwokindsofradiationandcontributingfactors.EvidencesuggestsahighlinearcorrelationofANRwithatmosphere-absorbedshortwaveradiation.wherebycanbeestablishedageneralexpressionforANR,whichdecreasesmoresharplyasafunctionofaltitudeandincreasesslightlywithlatitudeinsummer,andchangesuniformlyinwinter.Eventually,acomparisonismadeofthefindingspresentedinthispaperandliteraturesregardingtheANRpatternandmagnitudes,indicatingtheirgreatdifference.
简介:Thispaperdescribesandteststwomodelsforestimatingnetradiation(ortheradiationbalance)onslopingsurfacesofalpineenvironments.Theyareanempiricalmethodbasedonthelinearrelationshipbetweennetradiationandglobalsolarradiationandaflux-by-fluxmethodinvolvingtheestimationofalltheindividualcomponentsofradiationbudgetindependently.Theresultsshowthattheempiricalmethodiscapableofpredictinghourlynetradiationonslopingsur-facestowithinabout±53Wm-2underallskyconditions.Duringclearskyconditions,itcouldpredictnetradiationonslopestowithin±58Wm-2or16%ofthemeasuredvalues.Theflux-by-fluxmethod,althoughitdidnotperformaswellastheempiricalmethod,performedadequatelyandcouldgiveestimatesofnetradiationonslopeswithrootmeansquareerroroflessthan74Wm-2(20%)andameanbiaserrorof27Wm-2(7%).
简介:Weplantoestimateglobalnetprimaryproduction(NPP)ofvegetationusingtheAdvancedEarthObservingSatellite-Ⅱ(ADEOS-Ⅱ)GlobalImager(GLI)multi-spectraldata.WederiveanNPPestimationalgorithmfromgroundmeasurementdataontemperateplantsinJapan.Bythealgorithm,weestimateNPPusingavegetationindexbasedonpatterndecomposition(VIPD)fortheMongolianPlateau.TheVIPDisderivedfromLandsatETM+multi-spectraldata,andtheresultingNPPestimationiscomparedwithgrounddatameasuredinasemi-aridareaofMongolia.TheNPPestimationderivedfromsatelliteremotesensingdataagreeswiththegroundmeasurementdatawithintheerrorrangeof15%whenallabove-groundvegetationNPPiscalculatedfordifferentvegetationclassifications.