更新世晚期以来热带太平洋与印度洋

更新世晚期以來熱帶太平洋與印度洋之海洋初級生產力記錄OceanicPrimaryProductionintheTropicalPacificandIndianOceansDuringtheLatePleistocene言婉婷Wan-TingYEN國立台灣海洋大學應用地球科學研究所IntroductionReconstructingpastvariationsofprimaryproductionduringPleistoceneclimaticcyclesisanimportantrequirementforestimatingtheeffectsoftheocean’sbiologicalpumpontheatmosphericCO2concentrationthroughtime.Paleoproductivityreconstructionsshouldalsoprovideinformationaboutclimatedynamics.DiscussionENSOMaterial30°E60°E90°E120°E150°E180°150°W120°W90°W20°S20°N0°Analyzedthecoccolithophorecommunitypreservedinelevendeep-seacorestakenfromthetropicalIndianandPacificoceans.BytuningoxygenisotoperecordsfromforaminiferainmostofthecorestotheSPECMAPstackedrecord,samplingachievesatemporalresolutionof910000years.MethodsThecoccolithophoreFlorisphaeraprofundalivesinthedeep-photiczone.Asproductivityincreases,therelativeabundanceofF.profundadecreases.MethodsUsingtheleastsquaresmethodtesteddifferenttypesofequationstodeterminethebestfitforthedistributionofFpversusPP.PP=617-[279xlog(Fp+3)]Fpishighlycorrelatedwithprimaryproductionestimatedfromsatelliteinformation.MethodsCoretop的F.profundaBeaufortetal,(1997)衛星估計的ppMethodsPaleoproductivityestimatedfromindependentindicatorsisinverygoodagreementwiththeproductivitydeducedfromtheabundanceofF.profunda.Beaufortetal,(1997)MethodsBeaufortetal,(2001)TheePPrecordsshowlargeamplitudevariabilitywithregionalsimilaritiesandcontraststhatareexploredusingempiricalorthogonalfunctions(EOFs).010050128150Age(kyr)primaryproduction(gCm-2yr-1)Methods010050128150Age(kyr)Beaufortetal,(2001)TwosignificantEOFseries(EOF-1andEOF-2)havebeenextractedforthelast180kyfromtheeightcores.ResultsItgivesamuchclearerpictureoftheoppositionindynamicbetweenthewesternandeasternPacificePPs.Thiscyclicoppositioncanalsobeseenwhencomparingbasinaverageregionalrecords.Beaufortetal,(2001)30°E60°E90°E120°E150°E180°150°W120°W90°W20°S20°N0°ResultsBeaufortetal,(2001)冰期冰期間冰期間冰期ResultsBeaufortetal,(2001)ResultsA30-kyperiodhasbeenfoundinseriesfromthetropicalandtropicalIndianoceans.the30-kycomponentthatoccursinEOF-1aswellasinmostoftheePPseriescorrespondstoacyclicphaseshiftoftheprecessionparameter.Beaufortetal,(2001)30kyr30kyr30kyr30kyr30kyr30kyrDiscussionVariationsinequatorialproductivityareprimarilycausedbyglacial-interglacialvariabilityandbyprecession-controlledchangesintheeast-westthermoclineslopeoftheIndo-Pacific.Theprecession-controlledvariationsinproductivityarelinkedtoprocessessimilartotheSouthernOscillationphenomenon,andtheyprecedechangesintheoxygenisotopicratio,whichindicatesthattheyarenottheresultoficesheetfluctuations.Discussion(purple)：Thethreefilteredserieswerethenaddedtogether.Atthebottompositivepartof30-kyGaussianfilters(centeredon0.034ky21withabandwidthof0.004withcuttingatperiodof26.6and34.3ky)ofEOF.(green)：23-kysine-wavefrequencymodulatedby100-and40-kycyclefromSPECMAP.(orange)：–CO2fromVostok.Beaufortetal,(2001)ConclusionsThe30,000-yearspectralpeakinthetropicalIndo-PacificOceanproductivityrecordsisalsopresentintheAntarcticaatmosphericCO2record,suggestinganimportantroleforequatorialbiologicalproductivityinmodifyingatmosphericCO2.The23-kyENSO-likecycleislikelytohaveplayedasignificantroleinglobalclimatedynamics.ConclusionsTwoindependentforcingsresponsibleforthelong-termequatorialIndo-Pacificproductivitydynamics.1.Thedepthoftheequatorialthermoclinetoglobalclimaticvariations.2.Equatorialeast-westthermoclinetiltandislinkedtothe23-kyperiodofEarth’sprecession.嘗試利用衛星遙測所得之生產力資料與現有的岩心頂樣資料推估出一浮游有孔蟲之初級生產力經驗方程。所利用衛星資料：SeaWiFS區域：30°N~65°S，20°E~180°EMonthlyNetPrimaryProduction:February,2005未來工作參考文獻LucBeaufort,YvesLancelotPierreCamberlin,OliviaCayre,EdithVincent,FranckBassinot,LayrentLabeyrie,Science278,1451-1454(1997),InsolationCyclesasaMajorControlofEquatorialIndianOceanPrimaryProduction.LucBeaufort,ThibaultdeGaridel-Thoron,AlanC.Mix,NicklasG.Pisias,Science293,2440-2444(2001),ENSO-likeForcingonOceanicPrimaryProductionDuringtheLatePleistocene.LucBeaufort,T.deGaridel-Thoron,B.Linsley,D.Oppo,N.buchet,Science201,53-65(2003),BiomassburningandoceanicprimaryproductionestimatesintheSuluSeaareaoverthelast380kyrandtheEastAsianmonsoondynamics.