简介:Calibrationsbetweensodium(Na+)concentrationsfromaMt.Loganicecoreandsealevelpressure(SLP)seriesshowthatNa+concentrationsarecloselycorrelatedwiththeautumn-time(SeptemberOctober-November)Aleutianlow(AleuLow).AdeepeningoftheAleuLowstrengthensthetransportofsea-saltaerosolsfromtheNorthPacifictotheMt.Loganregion.TheMt.LoganNa+recordisusedtodevelopa292a(1688~1979)reconstructionoftheAleuLowrevealingadramaticintensificationofatmosphericcirculationovertheNorthPacificregionsincethe20thcentury.MeanSLPoftheAleuLowwasabout1hPalowerduringthe20thcenturythanduringpriorperiods.ThestrongestdeepeningoftheAleuLowappearedinthe1950s.SignificantcorrelationsarealsofoundbetweentheMt.LoganAleuLowproxyseriesandthePacificdecadaloscillation(PDO)andPacificcirculation(PC)indexduringthe20thcentury.Evolutionaryspectralanalysisoftheproxyrecordshowssignificantperiodicitiesfrom15to30aconsistentwithPDOfluctuationsandthebidecadaloscillationofNorthPacificatmosphere-oceancirculation.Aperiodof11aintheAleuLowrecordmaybeassociatedwiththeSchwabe11-acycleofsunspotactivity.AdditionallongericecorerecordsfromthisregionwillaidintheeffortstofurtherunderstandtheclimaticchangeovertheNorthPacificregion.