简介：Oftheworld'soceans,thePacifichasthemostabundantdistributionofseamounttrails,oceanicplateausandhotspots,andhasthelongestfracturezones.However,littleisknownoftheirthermalstructuresduetodifficultiesofheatflowmeasurementandinterpretation,andininferringthermalanomaliesfromlow-resolutionseismicvelocities.Usingrecentlypublishedglobalmagneticmodels,wepresentthefirstindependentconstraintonPacificgeothermalstateandmantledynamics,byapplyingafractalmagnetizationinversionmodeltomagneticanomalydata.Warmthermalanomaliesareinferredforallknownactivehotspots,mostseamounttrails,somemajorfracturezones,andoceaniclithospherebetween~100and~140Mainage.WhilemostCuriepointsareamongtheshallowestinthezoneroughlyboundedbythe20Maisochrons,abnormallydeepCuriepointsarefoundalongnearlyallridgecrestsinthePacific,relatedtopatchy,long-wavelengthandlarge-amplitudemagneticanomaliesthataremostlikelycausedbyprevailingmagmaticorhydrothermalprocesses.ManylargecontrastsinthethermalevolutionbetweenthePacificandNorthAtlanticsupportmuchstrongerhydrothermalcirculationoccurringinPacificlithospheresyoungerthan~60Ma,whichmayhavedisguisedfromsurfaceheatflowanydeepthermalsignaturesofvolcanicstructures.Yet,atdepthsoftheCuriepoints,ourmodelarguesforwarmerPacificlithosphereforcrustalagesolderthan~15Ma,givenaslightlyhigherspatialcorrelationofmagnetizationinthePacificthanintheNorthAtlantic.

简介：有由于季风系统的复杂性在中国预言植被回答到东方亚洲季风(电动会计记帐机)可变性的简单方法的缺乏。在这研究，我们发现了变化西方的和平的副热带的高度(WPSH)是EAM的主要部件之一，在中国在植被生长上有深刻影响。当WPSH更被定位到它的气候一般水准的西方时，东方、西北的部分分别地由0.3%-2.2%，和0.2%-2.2%经历增加的每年一般水准的规范的差别植被索引(NDVI)和粗野主要生产率(GPP)。相反，当WPSH更被定位到它的气候的东方时，平均，上述区域分别地在0.4%～1.6%，和1.3%～4.5%经历减少的每年一般水准的NDVI和GPP。WPSH用作一个主要发行量索引预言植被的反应到季风。

简介：Background:Volumeandtaperequationsareessentialforobtainingestimatesoftotalandmerchantablestemvolume.Taperfunctionsprovideadvantagestomerchantablevolumeequationsbecausetheyestimatediameterinsideoroutsidebarkatspecificheightsonthestem,enablingtheestimationoftotalandmerchantablestemvolume,volumeofindividuallogs,andaheightatagivendiameter.Methods:Usingdatacollectedfrom1218trees(1093Douglas-fir(Pseudotsugamenziesii(Mirbel)Franco)and125westernhemlock(Tsugaheterophylla)),weevaluatedtheperformanceofonesimplepolynomialfunctionandfourvariable-exponenttaperfunctionsinpredictingupperstemdiameter.SampletreeswerecollectedfromdifferentpartsofthestatesofOregon,Washington,andCalifornia.Wecomparedinside-barkvolumeestimatesobtainedfromtheselectedtaperequationwithestimatesobtainedfromasimplelogarithmicvolumeequationforthedataobtainedinthisstudyandtheequationsusedbytheForestInventoryandAnalysisprograminthePacificNorthwest(FIA-PNW)inthestateofCaliforniaandwesternhalfofthestatesofOregonandWashington.Results:Variableexponenttaperequationsweregenerallybetterthanthesimplepolynomialtaperequations.TheFIA-PNWvolumeequationsperformedfairlywellbutvolumeequationswithfewerparametersfittedinthisstudyprovidedcomparableresults.TheRMSEobtainedfromtaper-basedvolumeestimateswerealsocomparablewiththeRMSEoftheFIA-PNWvolumeequationsforDouglas-firandwesternhemlocktreesrespectively.Conclusions:ThetaperequationsfittedinthisstudyprovideaddedbenefittotheusersovertheFIA-PNWvolumeequationsbyenablingtheuserstopredictdiameteratanyheight,heighttoagivendiameter,andmerchantablevolumeinadditiontocubicvolumeincludingtopandstump(CVTS)ofDouglas-firandwesternhemlocktreesinthePacificNorthwest.ThefindingsofthisstudyalsogivemoreconfidencetotheusersofFIA-PNWvolumeequations.

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简介：Eoliandustpreservedindeep-seasedimentsoftheNorthPacificOcean(NPO)isanimportantrecorderofpaleoclimaticandpaleoenvironmentalchangesintheAsianinland.Tobetterunderstandchangesinthedustprovenances,inthisstudydiffusereflectancespectroscopy(DRS)wasusedtoextracttheeoliansignalrecordedinsedimentsofODPHole885ArecoveredfromtheNPO.First,wesystematicallyinvestigatedsievingeffectsontheDRSdata;thenbandpositionsofhematite(obtainedfromthesecondorderderivativecurvesoftheK-MremissionfunctionspectrumderivedfromtheDRS)wereusedtodistinguishdifferentprovenancesoftheeoliandustpreservedinthepelagicsedimentsofthishole.Ourresultsshowthatthesieving(38μm)processcansuppresseffectivelytheexperimentalerrors.EoliansignaturesfromChineseLoessPlateau(CLP)sourcesandnon-CLP-sourceshavebeenidentifiedinthepelagicsedimentsofODPHole885AfromthelatePliocenetotheearlyPleistocene.TheprovenancedifferencesaccountforthediscrepanciesintheeolianrecordsrecoveredfromthepelagicsedimentsintheNPOandprofilesintheCLP.Temporalchangesindustprovenancesarecausedbythelatitudinalmovementofthewesterlyjetmainstream.ThehematiteDRSbandpositionisausefultooltodistinguishtheprovenanceofeoliancomponentspreservedinpelagicsediments.

简介：TheregularvariationsinmagmaticactivitiesalongtheNorthwestPacificplatehavebeenlittlestudiedinspiteoftheirimportance.Inthiscontribution,systematicanalyseswereconductedontholeiiticbasaltsfromthreeOceanDrillingProgramsites（Sites304,1149,and801）,includingthepetrographicfeatures,majorandtraceelements,Ndisotopiccompositions,andmineralstructureandcompositionsofwholerocks.VolcanicrocksfromSites304,1149,and801belongtotholeiitesandexhibitdepletedlightrareearthelements（LREE）,largeionlithophileelementalcontents（LILE）,andrelativelydepletedNdisotopicratios（143Nd/144Nd=0.513139-0.513211）,similartothoseofnormalmid-oceanridgebasalts（N-MORB）.Comprehensivedataonmineralcompositions,whole-rockgeochemistry,andgeochronologydemonstratethataregularvariationtrendexistsinthenorth-southdirectionalongtheNorthwestPacificplate.The143Nd/144Ndvalues（0.513139-0.513211）andtrace-elementratiosforwholerocks（Sm/Th=15.35-30.00;Zr/Hf=28.53-35.76;Zr/Y=2.58-3.67;Th/La=0.04-0.06;Th/Y=0.33-0.70）,aswellasthetrace-elementratios（Zr/Hf,La/Yb,Ti/Zr）ofclinopyroxenesfromSites1149and801tholeiitesshowlargervariationscomparedtothosefromSite304tholeiites（143Nd/144Nd=0.513185-0.513195;Sm/Th=18.19-20.58;Zr/Hf=31.07-33.26;Zr/Y=2.62-3.03;Th/La=0.05-0.06;Th/Y=0.48-0.57）.MineralzoningtextureswereobviousintholeiitesfromSites1149and801butwererarelyobservedinSite304.Theseregularfeatureswerelikelyattributedtothedifferencesintheheterogeneityofthemagmasource,theprocessofmagmatieevolution,theplate-spreadingrate,andtheeffectiveandineffectivemixing.

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简介：IncontrasttopreviousstudiesthathavetendedtofocusontheinfluenceofthetotalArcticsea-icecoverontheEastAsiansummertripolerainfallpattern,thepresentstudyidentifiestheBarentsSeaasthekeyregionwheretheJunesea-icevariabilityexertsthemostsignificantimpactsontheEastAsianAugusttripolerainfallpattern,andexplorestheteleconnectionmechanismsinvolved.TheresultsrevealthatareductioninJuneseaiceexcitesanomalousupwardairmotionduetostrongnear-surfacethermalforcing,whichfurthertriggersameridionalAnomalousdownwardmotionthereforeformsovertheCaspianoverturningwave-likepatternextendingtomidlatitudes.Sea,whichinturninduceszonallyorientedoverturningcirculationalongthesubtropicaljetstream,exhibitingtheeast-westRossbywavetrainknownastheSilkRoadpattern.ItissuggestedthattheBoninhigh,asubtropicalanticyclonepredominantnearSouthKorea,showsasignificantanomalyduetotheeastwardextensionoftheSilkRoadpatterntoEastAsia.AsapossibledescendingbranchoftheHadleycell,theBoninhighanomalyultimatelytriggersameridionaloverturning,establishingthePacific-Japanpattern.ThisinturninducesananomalousanticycloneandcyclonepairoverEastAsia,andatripoleverticalconvectionanomalymeridionallyorientedoverEastAsia.Consequently,atripolerainfallanomalypatternisobservedoverEastAsia.Resultsfromnumericalexperimentsusingversion5oftheCommunityAtmosphereModelsupporttheinterpretationofthischainofevents.

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