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月a tlo n a11n s tlt u t e o f P01a r R eさe ar C h
M弧NadI皿舐.PohrR朗.,Spec.Issue,57,2=7,2003 ◎ユ0〔B N奴io血hsdtⅥle of Polar Researcb
∫dg′l聯e卿r
DatingortbeDome一両i,AntarctkadeeplCeCOre
OkitsuguWataJlabel,HitoshiSh房i2,KazuhideSatow3,HideakiMotoyamal, YoshiyukiFLtiiiI,HidekiNarita4andShttjiAnki5
1肋血戚血ばぬ漉ゲルねr属~∬d和布助卵ノィ加,血如∫掛れわ砂けノ乃-β∫ノ5
三助刑f肋gす旅ビ加〃ねg》Jお肋n-dp,肋刑f脚¢一郎β7
加聯血潮血血℃勅勘卵掴加地川棚純血姐御朝潮聯血欄-おj2 ●血!府政オ血w乃叩㈹血柁先王朗亡g,肋肋助かg叫
ぶぬ-ノ乳肋砧邑都ね-た埠軸押β和酬βJ9
5cビル鹿r♪rA加〃岬如rk〃舶伽gα戚亡餌如ね加h∽lルg柑i砂,
A和〝∽揖一昭1(l〃上峰Al)由一よ孔∫跳ねf9β仇β5乃
JWsbwL:TheAntarcticicesheetpreservespale8・Clim如in血mdiozlinthe鮎rnofphys-
k山弧dcbemic山s血dg叫y.Ade印icecαeW85COn血uou叫血山d血wnbad甲也of 2503m舶DomeFqjiStdion,E鮎IDzmningM机山Ⅰ』nd,Antazt:也ca.血鵬n$dle1993-97
JAREhl山do匹托dons.Oxyg孤is鵬叩e血蝕Su澤mbwe陀COnduckdon7to50cmlo喝
iceco托Saロplesselectd仕om也een血℃CO托d甲山.A血蛤SC山efbr血eDoⅡ蛤f叫ico托i5
Calc山虹d伽mpastacmmuladon融S弧d皿ice且owmo血1・Pastaccu血1濾on鹿W8Ⅳ COnVe血d蝕omoxyg蝕i50tOpeV血sbyusi喝皿e皿p最c山叫u也on虚血btkDome
F噌ia肥L Aste叫-S払蛤負owmddwas騨㌍iouslyd銅lopd触■a由比SCdecak山血n
or也モS血ticeco托,Gf恍血姐d.Ushg托飴珪Ⅸモd甲山p血b鮭omvd血si辞出血d
皿nu孔=叩α也ic血essY血esm胱don血emⅦ旭F咄eo托劇珊S伽仙血喝Or血ecal- CuhteddJneSCale.Adepth-agePm丘1ewasobtaiJICdhrthepast320kyr.
1馳e止血dp山eかt即呼出血此pfO山e血ows也ec血血dcsof也モp鮎l血托e匝i山
肌din吋g血i山pedo血.mepowe=匹C血mof即Oc血騨0Verani血eⅣ山of3加桓 代Ⅴ朗血山Ⅳedomh山l甲Cles.恥ep山eか愴m卿pm丘1ec血cidesqⅦitewe皿wi血【鵬
Vosbkiceco柁d血h騨nα山h止nolhde也山,S喝geS血g他山肋血dies鮎en恍dd
b鵬b鮎rchonol喝ic山hv朗d富鉱ions弧dam山d一触ctⅣ,CmSS棚Iadon叫Sisbetwe8m
d∝pio巳CO柁S鮎rcli皿慮dqgk山Ⅶn血路b皿dhg・
k町YOrds:d血g,DotneFqico陀.OXygenisotoperado,aAZru乱‖ayerthicb蛤SS,C山以止ic
dla皿ge
1∴血血・dⅦ鵬om
JapaLle$eAntaJt:ticResearchExpedidon(JARE)has由annedaJldexecl)tedtheDome FqjiProgranl,aCOm匹ehensiveglaciologicalresearchprogranfoctBmgOndeepICeCOn喝 andanalysisforretrievlngPaStenVironmentalinformationrecordedintheAntatcticice Sheet.Acon血uousd呵ICeCOredowntOadepthof2503mwaszecoveredatDomeFtdi Stadon(Fig.1),DmnmingMadLand,Antarcdca(77019t)l”S,39C42’12r℃:eleva血n,3810m
a.s.1.;icethi血ess,3028m;皿蛤anSu血eteppem山re,J7.3CC;Fqjitaetal.,1998)by usl喝aJAREmechaJlicaldrininahqtdd-filledholedmingthe1993⊥97fieldppcmtl皿S (Dome-FD∝pCoring伽up,1998).TYkCO托qualityisexce11entevenindleSlighdyb山一
25
Na tIon且1In s tlt u t e o f P01ar R e se ar c h
26 0.Wal弧ak gI‘止
月g・J・紬m椚〃伽吼如刑砂州軋馳血晰臥加仙丹瀕Ⅷ加加
tkzone一皿ghg如m550to糾Omdep血.
0ⅩygenisotopemeastJrementShavetmncomimouslymadebyMa(DdtaEom250r
50cm-longsampks(soc山kdbdfor血Ⅱbags弧1pks)細血at血ev血此肋血tev訂y50 yeaTSCOuldbeacquiredfromthewholeco托depth(Dorrk-FIceCoreReseaJ℃hGroup, 1998).TheI80/160radodbtainedbmeachsampleisconvertedto6J&0,therdativedevia-
tion打omthatinstandardmeanoceaJIWaW.Conseqth3ndy,theoxygendatavalueof6158 PleCeSWaSaCquired丘omthe2503mdeepcore.
ユ.M血帥・ghcb10癖職1ton心血耶訂○Ⅶ鵬Dome一再i
TheJapaJleSeAntamticReseardhExpedidonpartieshavecamiedoutalargenⅦ血of inlandtraversesontheAntaⅣticiceshectincludingtheSyowaTSouthPblero皿d叫)tra- VerSein1968-1969,aJldcollectedvaluableⅡ妃komlogicalandglaciolqgicaldata.Analyses Ofthescdata.suchasthet亡mPemturedistTibt)tionondleiceshect,LhcdistTibuLionofLhc
孔m旧ⅦntOfsnow誠Cmlation,姐dof血e血emis町Of弧OW,baveo鮎nproviddm¢W knowledge血ttheenvimnmentalconditionsofthesnowstHfhceinthisaJ%.The2ndE担t
㊥IeenMaudLandp亘iectstartedin1989・Gbdologicaldatahavebecncollectedalongthe
mversermtefromSyowaStationtoDomeF再iStadoninEastDmn血gMaudLandbya JAREfieldsuⅣey(Fig.1).System8丘csurfacetraverseresea血hasrevealedachBLraCteris-
ticrelationdlipoflOm-dqpthsnowtep(T;QC),and6J80value(denotedby6,per
H a tlon al In s tlt u t e o f p01a r R e s e a r c h
27 Dadng or血eDoⅡ蛤F鴫iice core
m址)(Bg.2)鮎托血由toelev鵬on加veseakvd(g;m)・ney肌d血da5払no耶
(SabWgJdJ.,1999)
∂=・■.01188(β-3810ト56.30, (1)
∂=0.852(7157.3)-56.74. (2)
TheO80valueisafunctionofthecondensadonte叩rattmOfvaporinthe拍nOSPhcre,
l
‾十
n
劇 棚 欄 馴
(○辞)虐葛■青書貞 ○ 洲 l伽■ 1剥仲 兄川○ 御○ 讃■● 到○ 朋O
E肋血) 鞄2.肋血即り血加¢肌m呵鮎川馴叫加d昭血机血血如何如助仙川血」押.乃~∫加な如
上f肘rlp相加g曾.〃ノ.
u
l - □ 一一--¶・一一・一1■-「ロー・-・
功 一 棚 馴
(○監虐】己暑昏貞
.1沖 .80 ■○ ■■ d● -10
M由m血削血t嘲叩畑山代(OC)
苅&j.肋劇即0囲血gげ眠〃ト∫〟ゆα∫柳クぬ伽d曙dお一椚gd乃〟m批山ゆgJ御中g相加柁(ノβ肝勾,助
∫乃のりお叩和加℃J(殖r血わWgIれJ卿ノ.恥∫細な加~如f∫が相打如g留.(2J・孤職サ血仙川血
C〃α∫I仙l血dわ甲gルe如ね川柁朗ご血由一♪り刑血聯∫∫わ乃g中畑Jわ鳳
N a tloIlalI爪S tlt u tを O f I〉01ar R8S¢ar C h
28 0.Watanah gIαJ.
弧d血e郡emge∂1800f血esnowpltOr血smowc耶Canbexp陀S虻dh也msof血e annualmeanairte叫阿a加代Whidhis叩FOXinwebTequaltodle10m-dq)thsnowte叫匹ra- Lure(Fig.3).Anempiricalequauonwasob血IedfbrtJlere]ationshipbeLweenaccumulaLi00 rak(Ao;CmOfioeequivalenVyear)aJld6180vahein血eareawith6≦-51%oqig.4):
A。=3.876e叩(0.1462(∂+55)). (3)
Equations(l),(2)and(3)dharacterimawiderangeamundtheDomeF両iregion,Wi血- OutaJlyfixedpointsfbrdataregressiom.Hence,nOneOftheseequ血sexacdy丘tpresent dayvahesobservedatDomeFqjiStadon.
(甲戸曾与貞呂。8。弓電卓∃
● ●
● ●
i l
J
l
ll
」
劇 .亜 屈 j4 j各 ・郎 劇
恥如叫血(%○)
鞠.イ.m憫加血坤庖佃朗肌肋血細川帆通知肌即の血町伊那明知…酬欄卸Ⅷ助川 血,一夕99J.乃g∫J和なぉJf即ねgん・例わIg¢(み
3.Da血g01仙eDomモF可id叩ke00托
The6J$ovaluemeasuredontheshallowcorefromDoⅡ妃Fdiis血【T55%00nan Ⅳer喝e(W紙皿血gJ正,1997a).叫鵬on(3)由vesam乱∝Ⅶ血donm随Ⅴ血eof3・876cm Oficeequivalen吟earatDomeFdiSta丘on,Whichis血out25%higherth皿themngeof2・8
to3.3cmoficeequivalen吋earobtaiJled蝕)mtheshauowc∝℃Study・恥fo1lowingequar 血nisassunedforthepastaccⅦm血donrateatDomeFqji・
Ao=βe叩(0.1462∂), (4)
whenBisaconstanttobedeterminedlater.
AtimescaleoftheDoⅡ蛤Fqjideqicecorecanbecalcula血byusingeq・(4)aJlda modifiedDansgaard-Jdlmsenmdel(Dam喝a訂detal.,1993)withflowmielparazELetqSaS ShowninFig.5;dleicethichess,H,ht血i虹eshearlayerthi血ess,h,Slidingl叩併 thichessatbedruk,S,andratioh:tWeCnthes血mratesatthebpoftheslidinglayeK(silqf ice)andatthesurface,ふTwo血ncedq)dlPOintsaresekctedfromvoIcanicsignalsat truedepthsof97.80m(2.338kyrBP;Watanabeetat・,1997b)and1849・55m(141kyrBP; F両道(Ⅵnpub鮎bd);F可最gJd.,1999).
Itwasdiscoveredthatthenu血de鮎ityofairhydra随Pardckss∝miJlglyvariessea-
Ⅳa tloIIalIn s tlt u t e of f101a r R e$¢a r C h
Da血g of血e DomeF両iic8C耶
鞠.5.耶l如汀如gβ亡わrカrd肋抽J
ゆ〝血血舶用血血適
わ,伽伽叩α撼・J〃ね那〃柁
〝l〃(おエ
● u u u ■■ 1
-Fi≒伽■■
(白)竜野白
● u ■▲ ■● ■轟 l
叫伽血■
乃&丘 乃血〃f喝βcわ「クrqβJg
の如〃f乃gdノb=如β〃椚g
瑚i亡〃柁・
Zla tIo rlal[TIS tlt ul:B O f Polar R e s e a r ch
30 0.鴨Ianak gJαJ.
sonallybetweenthedepthsof1100and2500mofdleDomeFdicore即aritaetal・,2003)・ Theanmallay訂thicknesscanbeestimakd如mthewidthofddsseasonalvariadom
Theicethicknessmeasuredbyradarechosoundingis3028土15m(WatanabeetaL▲, 1999),andairamtneaEthesurfhceisahout33.4natDomeFttji.¶leair鮎nOuI止WaS calculatedasfo1lows.Densityasafuncti皿OfdqpthwasdbtainedfromthedensiqTPrOfi1eof sllぬcelayers(Watanabeetal.,1997c).¶ledqdlWhenfirnbecomesicewassctto147・5 maJldthethi血essoftheicefromthesurfhcetothed印thwascalcdated,andthus血ethick- nessofairamMtWaSObtaiJd.
1m廟腱300OmisassⅥmd鮎rs坤C吋h血e喝e血Ⅲ1血(m・ne血owlaw paJlaLmeterSh,Sand.h,andBineq.(4),Were血teTminedsoastohaveealeul8tediceagesat
tworeferenαdepthsfitthevokamiceventages,andcalculatedammallayerthicknessvalues fitdIeaboveestimatedval1JeSdbtainedbyairhydratx:COⅦming.Icethidkne$Sisassumdto beconstantfbr血iscalcdadon.ThisⅡ蛤anSthatverticalstrAnrateischangingwith血Mさ thaticethicknessiskeptconstant,alth叫ghaccumiationratechanges・Thebestfitwithvol- caniceventagesandmlniberdensityofairhydrab=reSultedinh尋86叫Sgm,脚,aJld u=8975emoficeequivalcntJyca,・WiththisRvalue・2・89cmoficeequivalenUyciLris obtaincdfortkprcsentdayvaJueofaecumulationraleatDomeFLtji,WhiehagreesquiLewcll withthemeasⅧ陀dvahcwidhabout10%.neresultoftheddnningfactorfbr弧mal1ayer Cal血血misshowni皿F短.6.
4.TheJbturcsor&∝tLmtLbti仰&爪d8proJi]e
T71eaCCumulationrateand6profi1ewithdletimescaledbtAmedareshowninFig・7 (upper負gtlreS)・Theaccumlationratecorrelateswellwith血e8profi1e,beiJlgSmal1ina
glacialperiod,andlargeinaJlinterglacialperid・Tne6proRleclearlyshowsthreeglacial-
interglacialcyclesinaquitesimilarWaytO血eVostok6Dpro6le(JouzeletaZL,1996)(bd-
tom丘gureiJIFig,7).Al1m如OrLbaturesoJ)thetwopmfilescanbeeasilycompared・rrhe threeglacial-interglacialchamgesstronglyresembleeachothcrinlOOto120血ousand-year cycleswi血叩prOXimatelylO-thousand-yearOVerlap・Signi鮎aJltnlJCtuationscanbeseen
bothintheDomeFttiiadVostbkpro丘IesevenindleHolo∝nePeriod・TYledurationsof MarineIsoぬpeStages(MIS)l,6,70nthetwoprofilesmatehalmostexactly・However・MIS 6through9isabout7kyrshorter;eSpeCial1y,MIS6血r00gh7seemsmuchshorterinthe DomeF両icoreascomparedwiththeVostokcoTe・
Equadon(2)wasmdi負edtocalculatethetemperatLWedi鮎renceATbetwecnthepre- sentdayvalue(6=-55%oat7u7・3OC)andthepast【e叩ra山re,aSfollows・
dr=(∂+55)/0.852. (5)
Thepaleo-temperaturePrO丘Ieobtained(Fig・8)showsavariationofapproximately lOOCbetweenglacialandintぽglacialpe正ods,Whichseemstobeclosetobuta鮎wdegleeS largerthandleT-VariadonatVostok・Thedi飴renceintemperarureOflOOCbetweenglacial
andinterglacialperiodsissimi1artothete叩aturedi鮎rencedbtainedfrom血esumitice
coreofGreenlanditltheArcdcregion(e.g.,Grootesetal・,1993)■ Also,inalongglacialperiod,thebigchangeof4to6OCil)thetempera山redi脆陀nCe
isalsosecrL.Mo托OVef,thetendencytowhichthesinJationofthete叩reCharLgeWaS verysimi1arisshownamongtheglacialperiods,eSpeCial1yin血eWisconsinageperiodand
H a tlon alIn s tlt u t0 0f ア01a r ll¢S e a r C h
31 D血gof血e Do血合F両iiceco托
一-一欄一一
(●さ) ▲r鴫
● ● 】■● 1●■ ■■ 篇● ]■● 1■
■■巾■■叫
鞠け何針巾叫掛血ぬ血I加桝ゼ∫ゆ.ノke銘仙血血乃和鍵,ん如止血血脚肌叫㈹=小町叩卿 〃加〃f舶dα侮ねた(鍵rJ〃昭gJgI慮,J99¢タd舟gI正.ノ99乳〟搭搾油Ⅳ〃相即肋∽陀d血血w推
加如励仲山納材鋸
Do血鎗駒埴
(p) ↑■
● 一 一 一一
O t■ 1卿 15■ 】■○ 蜘 】■● 蜘
Ⅵ■b■
●
p ヽ′ .さ l■
■ ▲
■
J
.加
○ 馴 1■0 1寧● 】■● 蜘 ■■● 脚
■■伽■椚
F隠β.血ゆcg岬和知柁V〃ガ〃血旧劇加配∫頑f劇d侮此血詑叩〝油化d脾傭αArdJ加旬fお
“J仁政おdノわ桝g留・(斗ArdIlわ∫わた払鍵rJ〃昭gJdI‘りJ99卵αdJセ由gId・(J9卵J・
Na tlo n al In s tlt u t e o f P ola r R e s e a r c h
32 0.Watama鮎~J〃J.
thenlinoisageperiod.N戊eWOrthyisthefhctthat血8highestte叫匹ratureOftheHol∝ene
is2to30Clowerthanthoseoftheinterglacialperiods.馳chglacialperiod血ishe$Wi血a Suddenrisehte叩mttm.Althoughthemimimtem阿a山花StartSjustbefbretheendof aglacialperiodintheWisconsinage,thisisnotthecaBCin血eothcrtwoglacialpedods・
5.S阿山a丑山y由
Inordertodetectprevai1iqperiodicitiesof6180variadonoftheDomeFqjicorecov- erizlgaPeriodof血t320kyr,SPCtralanalysisbythemime腑Opyndod(MEM)
WaSaPPlied・Theuppe,丘gureofFig・9showsthespectral匹WCrVerSuSthe鮎quency,and theloweqfigtmthe平C血powervemtutheperiod.TYmdominaJ)tperiodicides打eSeCn
atlO2桓ー,40桓ー,弧d21桓ー.m彷e匹並s打℃おS∝i血wi血血恍巧Cks止血¢猥仕Ot nomk山血e明yOfM鮎血vitch,f.g.,血ecyckofeccen血叫ば血ee血’so血址(1(旧k叩),
thecycleofobliquityoftheearth’saxis(41kyr),andtheprecessioncycleoftheearth’saxis
(23kyrad19kyr),reSPatively.The6D(wisotopictempqatu托)variadoninthe420kyr Vostokic¢COreShowsprominentcyclesatlOOkyrad41kyr(PedteEal.,1999;Mdlerand MacDon血d,2αX)).
榊 柳 川
量】巴臣9h
● 2 4 ● 8 10
匝甲(1♂呼嘲
馴 刑 期 畑
星塾巨9丸
1 1● 封檜 1帥
仙帥
苅g.9.タ〃Wgr岬gC細別げ即0亡如呼♪r〟Ig∫20砂rエI〃刑gFゆわ‘C〃柁・乃gJ印加柁
血剃摘削坪頭叫押仰m椚射血ゆ叩脚(顎dJ山鹿お批明、鹿〟柁∫血相∫Jお坤α血J
卵仰川刑肌血卵油d乃…朗通一朗おM通Ⅷ用沌血Ⅷサ
封a tlo n al ln s tlt tlt e O f P01a r R e s e a r cIl
33 D血gof血eDomeF両iice co托
Rbsultsofthes匹Ctmmana吋siscoverizlgthepast血托egl紅ialperiodsamshownin Fig.10.Prominentcycleswendbtainedat135kyr,42桓and24kyrintheWisconsin glacialperiod,atl鵬kyr,34kyrand21kyrintheIlliJ)Oianglacialperiod,andatl16kyr,51 kyr,and27kyrintheKansanglacialperiod.ItisthoughtthattheiSeremarkablecyclesof ea血gl虹i血匹虚血co汀eSpOndtoMil血扇t血cycles・
脚 朋 卿
畳h筐rOh
l0 100 1OOO
旭d陶巾
脚 鵬 劇 畑 。
自己ち山邑¢■山岳rクー
10 100 1伽
れ訂hd O甲巾
脚 帥 棚 洲 。
星hむ岳・£h
1 10 11XI l嘲
れ当良■(b巾
鞠.ル 伽wgr甲gαⅦ♪rgα烏g由仁由一♪g沌適加納g加〝好瑚ほぞ亡〝柁・馳〝〃Wgr即■朗抽叫加
J鮎恥亡の那加gbdd匹「わd如h珊乃加助g叩pα彪“陀仏い♪r如皿加∂ね叩gd〃d加仇e
所以k伽柁仲JJ♪r助g助Jび胡g由仁ねJクgrわd加血J仰gr彪〟柁(q・乃ゼVのサわd一血∫
血Iれ卯抽ね叩
H a tl011al In s tlt u t0 0f tIola r R e s e a r c h
34 0.Watan血gId.
‘.A血m吐血1ayert出血怯S
Tbinvestlgatethedi脆rencebetweenDozrLeFttjiazldVostbkcoredataindetai1,dle annual1ayerthickness(cmoficeequivalent)withdepth,agOOdmeasurefbriceflowcondi- don弘光$Sment,WaS既血.ne托S山bob血da托SIlOWnh抗g.11fbrDoⅡ蛤F両ia血 Vostokdab,reSPeCdvely.Amual1ayerthidknessgeneral1yd∝托aS¢SWithdq)th鮎rdle DomeFttjicore,withsm姐in耶aSeSdminglnterglacialaJldintemtadialpedods・Howevq, itisalmostconstantduringglacialperiods(WiscomsinandIllinoian)fbrtheVostbkcore・ ThisⅡ好8皿尽dlattheiceflowcondidonatDoⅡ妃Fttiiisquitesimpleascomp乱陀dtoVosbk,
Whe陀“tunl喝”andbr“m∝l姐cadon”with0thqdataisn従dedtodbtmitheicechmnology・
OnecanexpectthatforDomeFdi,Onlyaminor“md述cation”wi11berequiredbraⅡ灯e 托h血1eicecorechonologyin血e細山re.
ぴ ‡ 日掛.一代 l 貼 ○
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仰打払(c加叫♪r上)〃〝ば瑚り坤伽呵助d〃桝掴J旬姥「めわた榔ク叩坪gcd加ゎ〟dカrlわ肋た伽ト
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35 Dad【唱Of血e Dome F噛iiee亡0Ⅰ℃
7.AnestimateoE6180variationbebw2500m
ThedeeperPartOfthecontimousVostokcorehasbeenextracted,andprelirmnary resultsrqported(PetitetaL.,1999).Mqior鈷aturesseemtocoincidequitewellbetween6■80 and8Dvaria也onsequencesrepresemingthehemisphericalclimatevariation澤COrd・
OneoftheprincipaladvantagesoftheDomeFdicoreisthesimphcityoftheflowcon- ditionaroundDomeF両idownto2500mdepth,aldlOughdleflowindeeperPartSShouldbe
fur血erex鮎rlined.Anestimatewasmadeofthenurnberofglacial-in[erglacialcycles,血ich
mighexistbelow2500mdq)thattheDomeFttjiconngsite・Thefo皿0wingcalcula[ion methodwasfirststlggeStedbySigfusJbhnsen,Denm血生(unpublished)・AssumingthatMIS 2through7ewi山berepeatedbelow2500mdqpth,the6J&ovariadonwascalculatedas ShowninFig.12,Whid=血owssixrmcyclesdowntoadepthof血out2820matapprox- ima工elyonemillioJlye訂Sbeforethepresent.
¶1equeSdonarisesastowhetherifⅡ氾1eculardiffusionsm00thsoutthe61$ovariations・
Ⅵleice血icknessfor血eoldestcycleisabout20m,Whidhiscomparabletothedepthinter- ValforWisconsiniceobservedinRenlandicecap,Greenland(JohnsenetaZ.,1992)・
However,thedi蝕siondistanceforH2180moleculeshouldtxtentimeslongerforahtlndred timeslongerperid,Whichmaysmoothoutthe6180variation・Quiteencotlragingisthatthe
6I80profilesobtained丘omDevonIslmdicecap(Patersonetal.,1977)revealclimatic Changeinfbrmationduring血eWisconsinageperiodfromadepthintervalofafbwmeters Only.TY)edepthcouldbeshallowerandthedqth-inkrvalcouldbeevenshorterfbrthelast CyCle,ifMIS8and9havesh∝tertimeperidsasshownintheVostokicecore■Insucha case,muCholdericemightbedbserveda[2820mdepth,farbeyondtheageofthebo江Omice a[Vostok,althoughthere扇evalofdetai1edinformatiot)COuldbedi爪cultforsometypesof COreanalysis,SuChasgasamalysis.
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臥CoれClⅥSbms
AtimescalefbrthebmeFqjiiceeoreiscalculated血ompastacctmladonratesand anice且owmodel.Them毎OrfbatufeSOfdleDomeF頑iicecoredbtainedwiththissin甲Ie
Ha tlon alIn s tlt11t e O f P01a r Re$e arC h
36 0.Watanah gIdJ.
丘owmodelcalculationa陀SunHnarizedasfollows:
1)A皿m再α飴amresofM鵬neIso叩St喝eS(MIS)No・1血n川由No・9a托托00g血d Widlin血tlO%unCertaintyintimescale.
2)¶le6Hoprofi1ewiththecalculatBddmescaleshowsthattiudtmdonofMISl,6,7 matchesalmostexactlytothatoftheVostbkpmfile,butMIS6血ro叫gh7is血dercom・ paredwiththeVostokcore・
3)nem血mtepperattmdi飴rencetxtweenglacialandinteqglacialperiodsis血t lOqC,aJ)dat叩atLmraAgeOf4to60Cwasdbservedintheglacialpedods・
4)Thehighestte叩rattmOftheHoloceneis2-30ClowerthanthatofthepastthreciJ)ter- gladd画ds.
5)血ge血,血e肋叫血℃Vada点onp批汀n餅肌idemdcdto血虹Of血eVosbkco托 data,butdleamPlittxIeseemsafewdegree$1argerthaJldlatintheVostbkdata・
6)¶leSPeCtrtmanalysisofthe6J80dhaJlgebrthepast320kyr血owsdtreedominaJlt 匹aks:102ky,40ky姐d21kyr・
7)¶leice且owco加地onatDoⅡ妃F頑k托kdvelysimpkasco叩訂edb血eVosbkloca- tion,andpossiblysixmo托glacialcydesndghtbedbsαVedforgldbalchaJlgei血・ don.
Th粥妃f加dhgss江Omgly叫脚鵬血ep血∞-C鮎na随肋m瓜b皿血t血dh血eVostok coredataingeneral,ands叩PdthehypodleSisofasinpleflowconditionatDoI批Fdi・ ChronolqgicalacmyforthistinescalecalcuhtioncouldbeestimabdtobeabmtlO%点灯 long-temVadadons.FurdlerStudiesarerqdiredforthecorechronolqgyoftheDomeFqji Sta血ndeepco托.Cross-COrreladonanalysisof6I80valueswithotherdatabyPhysicaland chemicalstudyontheDomeFQjiicccorewinrevealwdeta濾edinfomi皿皿Paleo- CliⅡ迫dcdhaJlgeSin血合south併nhemisphere・
AchowIdgmen也
ThiswoLkisacontributionoftheDomeFtdiPbgmWethankJAREparty加血krs aJldcouabcmtwsfortheircopperadveefEbrts.We血ankDr・SigfusJdhn錐n,Universityof Cppenhagen,DenmaTkform弧ySuggeSdonsanddiscussions・nisworkissuppor随dbya GraJlt-in-AidforSciemificResearch(No.10204101)蝕)ntheMinistryofEdllCadon, CulmⅡ℃,Spo正S,Scknce弧dTbdmdogy,Japam■
R曲ー也l亡eS
DansgaAd,W・,J血sen,S・,Clausen,H・.Dahl-J孤Sen,D■,G皿destruP,N・,HanJner・C・・Hvidbeg,C・・Ste蝕nsen・J・,
Sv血叫omdot也A.,JoⅦel,J.皿dBo血,G.(199ユ):E扇血nceぬ【騨nemlhぬb揖ⅣOrp鮎t亡1血紆om
礼250㊥ric¢-C耶耽0血Na加e,3吼2i81犯 Dome-FDeepCoringGroup(1998):tkepicc-COZCddJJihga(DomEF咄andglaci01喝icaIstudiesineBLStDfOnning
M孤山血d,A皿t鋸℃lk乱Ann.01拡id.,27,333一っ37.
Dome>FIceCoreRescarchGroup(1998):Prdi血鮎yinvesdgdionofpdamcLimdesigndsrecordedintheice eαe伽mDoⅡ迫p咄Stad叩.8鮎tDm皿hgM孤山Lmd,Ant幻℃血礼Am■Glaciol■,ヱ1338」42・
叫ii,Y.,Ⅹ0血0.M.,Motoyana.H・,Mab吼S・,Watan血,0・,Fqjita,S・,Aztn礼N・.鮎血chi,T・.Fbmiwa,TaAd
Suzuki.T▲(1999):TephrahyersintheDoneFqji(A.ntax血4)deepicecore・Ann・Gl拡iol・,29,126-130・
Fqjit&.,S.,馳meda,T.adF両ii,Y.(1998):Glaciologicd血hco11ectedbythe37thJapaAeSCAntarcticExpeditions
d血喝19!略一1997.〟lREDぬR印.,2封(Glacidogy訂),∠帖p.
Grootes,P.M.,Smiv曙.M.,White,J.W.C.,JQhsen,S.andJ仇l訟1,).(1993):Comparisonofoxygenisotope托COrds
N a tloIlalIn s tlt u t e o f P olar R e s e a r c h
37 D孔血gor血eDomeF噌iic8CO托
蝕om血80ISP2andORIPG托e山andiceco托S.N鵬31拓,552-j54.
Johns印,S.J.,Chusen,H・B・,DaLnSgaaZd,W・,Gundes血p-N・S・,H&nSSOn・M・・J皿SSOn,P■,Ste飴nscn,J・P・笹d
Sv8h叫Omdo血,A.E.(1992):A“de印’’i¢8eO托仕om払stG托e山皿血Mdd・伽弧1・,0∞SCi・,2鶏
1」乙2.
Jou㌍l,J.,W脈1bm∝kC.,M血,8.,Bmder,M.,比丘り.k,Sd餅肌a吼M.,且虹kov,N.Ⅰ.,B鉱nOhJ・M・,鮎ng, T.,Kotlyakov,V3d.,Lipenkov.V.,Lerius.C■,RqTnad,D・,Ritz,C・血Sow耶,T・(1996):Cli血c h叫托はdonon血e代Ce叫鉄也nd由Vost慮ic亡児CαdC止mDyn・,12,513-j21・
MuILer,R.A.旭dMaJCDon山d,G.J.(2000):IceA辞SandAstmnomicalG仙SeS:Data.SpectralAnalysisand M∝h弧ism.C出血cst吼318p.(S騨hgeト取乱isbobine血山sdmc¢S)・
Narita,H.,Azttna,N.,Hondoh,T.,Hod,A..HiraDntSu,T..瑚ii-Miyamdo,M.,Satow,K,Sh鴎H・aAdWatiLn止e O.(2003):Es血n舶onor皿Ⅱuall叩訂鮎血8SSfぬms旭i騨申出cal皿81ysisof加meF両i血印ic8eO陀・
MemN血Ih乱Po血Res.,S匹C.Issw,5138一博・ Pal耶On,W.S月.,Ⅹoe∬,R.M.,Fi血ー,D.,J血s叫.SJ.,Cl皿S8n,H.B,D油島g乱打札W.,Bu血α,P.狐dOeschger,
H,(1977):A皿OX輝n-iso嘩Clim如k耽α止血m也eDcⅦnIs血dice叩,a血cGm血・N細山毘,劫妬, 50日11.
Petit,J.R・,J00比1,J,Rayn揖d,D・,B札止ovIN・Ⅰ・,B鎚Wla,J・M■IBiLSiIe,l・,Bendcr・M・・Chappeuaz・J・・DBLVis・J・・ Dehygue.G・,D¢血otle,M・,Ⅹotly血v,V・M・,Legrnd・M■・LipeAbv・V・Y・,Lerius・C・・Peph・L・・Ri吼
C..Saltz;maZL.E.andStievenard,M.(1999):CJidand釦InOSPherichistorybfthepas(420,00yews 鉦om血eVost【血ieeeαちA皿taⅣdc乱.N細,3!抄,429一斗3‘.
S鉱OW,鼠,W血mbe,0.,S血頑,H.血M戊叩叫H.(1999):’me托1alio叫皿ga仁山m山血m融,封鼠bkisか 叫emlio皿dte叩皿血eplぬmofE鮎tDm皿i喝M混dl劇d,Anta通日L n∝・NⅣRSymp・ Pol訂Me也Oml.81a亡id..13,43-j2.
Wab皿abe,0.,Ⅹ血y孔m孔.R.,M¢by孔叫H..Ig血i,M・,M瓜虚礼S・,S鮎ー扇w礼Tt,Ya血且(k,T・,Sbqji,H・,
馳m封n血S.,馳姐Ⅱ旭丘,N.,N血Ⅵ〉,M..A紳Y.,Ⅹ○醇,S.弧dS釦OW,鼠(1卵7可:P托血血叫叩甲鵬
onzLndysesofmel(6dDomeFtdicoreob血din1993・Phc・NⅣRSymp・PoIarMetcoml・Gl∝iol・,11, 1Jト23.
W水仙血兜,0.,叫軋Y.,Md叩am礼m,旭W礼T・,S叫いL払omぬ,H・,蜘T・,N鵬吼H■,N肌Se,鼠・ Hondoh,T,,FLdi也,S.,Mae,S.,A凱叫N・,Kobayashi,S・,Nakawo,M・andAgeta.Y・(1997b):Aprelixnr
h町yS叫ばieeco托dlmnOIp訂鉱DoⅡ泣叫iS餌i皿.Ant廻℃也孔触・潤Symp■P血Met∝肌止・ Ghcbl..11,㌢・13.
Wa(an血,0.,ShinuLda.W.,Narita.H.,Miyanoto,A.,Tayuki,K・,Hon血h,T・,KzLWaJqT・,Ⅰ叫ita.S・,S叫i.H・,
EnomdqH.,馳山地血,T.,K乱WぬK.血Y血y叫鼠(1997c):P陀1血血Ⅳ曲蝕S血norp吋Sk山 p画朗ば血eDo皿ef叫i血畑owic¢CO托im19汎A皿血℃血乱Pmc・NⅦ円iSymp・ね18rM触∝d・ 01aciol.,11,1-8.
W加皿ak,0.,馳山yⅢnも鼠,Moby払m且,IL鱒iii,Y.,S血(払Ⅱ.沌dSatow,Ⅹ・(1999):me画眈1血且蛤爪光0河
山t鮎iceco爬atDomeF噌St鵬on,E鮎【A地肌tic乱A皿・Gl肛id・,乳17ト178・
仲加地”招血酢=伽打払如山肌蛸ゆ摘明卿膵肋w車り弧