Remarkable Link between Projected Uncertainties of Arctic Sea-Ice Decline and Winter Eurasian Climate

(整期优先)网络出版时间:2018-01-11
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Weidentifythattheprojecteduncertaintyofthepan-Arcticsea-iceconcentration(SIC)isstronglycoupledwiththeEurasiancirculationintheborealwinter(December-March;DJFM),basedonasingularvaluedecomposition(SVD)analysisoftheforcedresponseof11CMIP5models.Inthemodelsshowingastrongersea-icedecline,thePolarcellbecomesweakerandthereisananomalousincreaseinthesealevelpressure(SLP)along60°N,includingtheUrals-SiberiaregionandtheIcelandlowregion.ThereisanaccompanyingweakeningofboththemidlatitudewesterlywindsandtheFerrellcell,wheretheSVDsignalsarealsorelatedtoanomalousseasurfacetemperaturewarminginthemidlatitudeNorthAtlantic.IntheMediterraneanregion,theanomalouscirculationresponseshowsadecreasingSLPandincreasingprecipitation.TheanomalousSLPresponsesovertheEuro-AtlanticregionprojectontothenegativeNorthAtlanticOscillation-likepattern.Altogether,pan-ArcticSICdeclinecouldstronglyimpactthewinterEurasianclimate,butweshouldbecautiousaboutthecausalityoftheirlinkage.