摘要
Adiscrepancyremainsinthefirsttwoleadingempiricalorthogonalfunction(EOF)modesofthetropicalPacificseasurfacetemperatureanomaly(SSTA)basedonobservationssincethe1980s.TheEOF1mode,representingtheElNino-SouthernOscillation(ENSO),isarobustresult.However,theEOF2featureseitherElNinoModoki(EM)orENSOevolutionduringdifferentperiods,whichisprobablyassociatedwiththeimpactsofglobalwarming.TheunderlyingquestioniswhattheEOF2modeofthetropicalPacificwouldbewithoutglobalwarming.UsingtheCMIP5preindustrialscenariotoexcludetheinfluenceofglobalwarming,wefindthattheEOF1modeofthetropicalPacificSSTArepresentsENSOandthattheEOF2modeisnotEM.Accordingtothelead–lagcorrelationbetweentheENSOandEOF2modes,thelinkagebetweenthesetwomodesisasfollows:…ElNino→EOF2→LaNina→–EOF2→ElNino….Byanalyzingtheevolutionofseasurfacetemperature,surfacewind,andsubsurfaceoceantemperatureanomalies,wefindthemechanismlinkingtheENSOandEOF2modesistheair–seainteractionassociatedwiththeENSOcycle.ThisresultsuggeststhattheEOF2moderepresentsanaspectofENSOevolutionunderpreindustrialconditions.Therefore,thisstudyfurtherindicatesthattheEMisprobablyduetotheinfluenceofglobalwarming.
出版日期
2019年02月12日(中国期刊网平台首次上网日期,不代表论文的发表时间)