BulletinofGlaciologicalResearch20（2003）65−72

郎⑥JapaneseSociety ofSnowandIce

AnoverviewoftheJapaneseglacio10gicalstudieson Mt．Logan，YukonTerritory，Canadain2002

Kumiko GOTO・AZUMAl，TakayukiSHIRAIWA2，Sumito MATOBAl，Takahiro SEGAWA3，Syosaku

KANAMORl2，YoshiyukiFUJlllandTetsuhideYAMASAKl4

1NationalInstituteofPolarResearch，1−9−10Kaga，Itabashi−ku，Tokyo1738515JAPAN2InstituteofLowTemperatureScience，HokkaidoUniversity，Kita19，Nishi8，Kita−ku，SapporoO60−0819JAPAN

3BiologicalLaboratory，FacultyofBioscienceandBiotechnology，TokyoInstituteofTechnology，2−12rlOokayama，Meguro−kTokyo152−8551JAPAN
4Avangnaq，723Nagasawa，Otokoyama，Yawata−Shi，Kyoto6148367JAPAN（ReceivedOctober3，2002；Revisedmanuscriptreceived November6，2002）

Abstract

During the spring of2002，We reCOVered a220．52mice core and made relevant glaciologicalObservationsonMt．Logan，YukonTerritory，Canada．Thispaperoutlinesthe2002fieldstudiesanddescribesthecoreanalysesthatareplanned．Meteorologicalmeasurementsandstratigraphyofthe

COreandapitatKingCol，thedrillsite，indicatedverylittlesummermeltingatKingCol．Theannual
SnOWaCCumulationrateatKingColbetweenMay2001andMay2002wasO．6mw．e．，Whichisonly

athirdtoahalfofthatforthepreviousyear．

1．lntroductionTheArcticisakeyregionbeingstudiedtogaina
betterunderstanding ofglobalchange．To definethe
Spatialandtemporalvariabilityofclimaticandenvi−

ronmentalchanges across the entire Arctic，theIce−
Core Circum−Arctic Paleoclimate Program（ICAPP）
wasinitiated under theInternationalArctic Commit−tee（IASC）andPastGlobalChanges（PAGES）oftheInternationalGeosphere・Biosphere Programme

backintime，andacorefrom anintermediateeleva−
tionneedstoberetrieved．In2001and2002，icecores
Weredrilledat Prospector−RussellCol（5340m a．s．1．）
OnMt．LoganbyaCanadianteam，atKingCol（4135m a．s．l．）on Mt．Logan by aJapanese team，and onEclipseIcefield（3017m a．s．1．）by anAmericanteam，Relevant glaciologicaland meteorologicalobserva−
tionswere also made duringthe2000r2002field seaNSOnS．

The objectives ofice−COre drilling and field（IGBP）．SincetheinceptionofICAPP，SeVeralnewice Studies at King Colare to understand（1）decadalcores have been retrieved from sites having littleice−COre data（e．g．Fisher et alリ1998；Grumet et alリ
2001；0 Dwyer et al．，2000；Watanabe et al．，2001；
Goto−Azuma et al．，2002；Yalcin and Wake，2001）．
However，mOSt paStice・COre Sites have beenin thevariations of climate in the North Atlantic sector oftheArctic，（2）historyofanthropogenic airpollution

andtransportationpathwaysoftheairTpOllutants，and（3）flow dynamics of a cold mountain glacier．Thispaper presents an overview of the field studies done

North Atlantic sector of the Arctic．Ice core records
On Mt．Loganby theJapanese teamin2002，andfrom North−West Colon Mt．Logan（Holdsworth et OngOinganalysesoftheKingCoIcore．
al．，1988；1992，Mooreetal．，2001）andEclipseIcefield（Yalcin and Wake，2001）in the Yukon Territory，
2．Fieldwork

Canadahavebeentheonlyicecoreproxydatafrom
thewesternNorthAmericanArctic．Duetothelargeelevationdifferencebetweenthetwosites（formerandご」．凡−∫（VJ・（、／〜肌、／′！イJん，JDuringthe2002field season，theJapanese teamlatterbeing5340and3017ma．s．1．，reSpeCtively），they
didthefollowingfieldstudiesonMt．Logan，Yukon
aredistinctrecordsdespitetheirproximity．
Territory，Canada（Fig．1）．
To better understand altitudinal and temporal（1）IcecoringatKingCol（KC）toadepthof220．52m

Variability ofclimatic andenvironmentalchangesin
the North Pacific sector of the Arctic，Whichis one

ICAPP goal，theice−COre reCOrds from North−West

ColandEclipseIcefieldneedto be extended further

with an electro・meChanicaldrill．

（2）BoreholetemperaturemeasurementatKCinthe
220．52m−deephole．
（3）On−Site stratigraphy observation and processing

66

BulletinofGlaciologicalResearchof the220．52m core．

（4）Icethicknessmeasurement atKCbyradarecho

SOunding．

（5）SurfacetopographysurveyatKC．
（6）Strainnetmeasurement atKC．
（7）Snowstakemeasurement atKC．
（8）MeteorologicalobservationsatKC．
（9）FreshsnowsamplingatKC．
（10）Snow pit studiesincluding pit−Wallsampling at
KCandQuintinoSella（QS）．

ingboreholes．

（12）Measurements of body temperature，pulse rate
andbloodoxygencontentatQS，KingTrench（KT），and KC．

Most of the fieldwork was done at KC because thefirstpriorityofthe2002fieldcampaignwastodrillan
ice core there．A photograph of KCis presented byShiraiwa et al．（2003，thisissue）．Dates of the major

fieldstudiesaresummarizedinTablel，anddetailsof（11）IcecoringatKCandQSwithahandcorerand （1），（2），and（4）−（7）are reported by Shiraiwa et al．
boreholetemperaturemeasurements ontheresult−

15km1

1側y5αW（2003，thisissue）．

14ぴ00 W

140030 W

Fig．1．Mapofthefieldstudysites．（a）LocationofMt．Logan．0））Studysites on Mt．Logan．QS：Quintino Sella（2800m）KT：King Trench（3300m）KC：KingCol（4135m）PRC：ProspeCtOr−Russe11Col（5340m）
NWC：North−West Col（5340m）

Azuma ggαJ．

Tablel．Datesoffieldstudiesandlogisticsin2002

67

BulletinofGlaciologicalResearch（廿2．2．〟g，刀占β作TheJapanesemembersofthe2002fieldcampaign

are as follows．

Kumiko GotoTAzuma（NationalInstitute of Polar
Research）：1eader andglaciologist

TakayukiShiraiwa（Institute of Low Temperature

Science，Hokkaido University）：Chief driller andglaciologist
Sumito Matoba（NationalInstitute of PolarResearch）：Chemist
Takahiro Segawa（TokyoInstitute of Technology）：biologist
Syosaku Kanamori（Institute of Low Temperature

Science，Hokkaido University）：glaciologist
TetsuhideYamasaki（Avangnaq）：driller

2．3．ム砂如b
Theeasiest accessto Mt．Loganisto flyto QS．

Wehavecharteredaturbo−ChargedSingleOtterplanefrom the Alaskan aircraft operator Ultima Thule
Outfitters，and flewin the personneland equipment

fromChitina，AlaskatoQS．Thepersonnelthenskiedfrom QS to KT for acclimatization，andmost of theequipmentwasflowntoKContheSingleOtterplane．
ThedatesofourlogisticoperationsonMt．Loganaresummarizedin Tablel．

We had orlglnally planned to use the Alaskan

and direction were measured with an anemometer

installedonatripod．Allmeteorologicalobservations
Were made bothin the morning andin the evening．
Results are shownin Table2．Air temperature andWindspeedareplottedinFig．2．

KC was frequently coveredwith clouds or fog，Whichdelayedouraircraftmission．WindspeedatKC

WaSuSuallybelow5msJl．Duringourone−mOnthstay
atKC，therewasonlyonemajorwindstorm．Itstarted

in the morning of May 20，1asted untilthe early

evening，andbentafewpolesofthedrilltent．Italso

SCOuredthe newsnowthat depositedduring May13−17；SnOW depths measured with snow stakes de−
CreaSed by about O．1m（Shiraiwa et al．，2003，thisissue）anditformedsastrugi0．10．2mhigh．Airtem−

peraturesinthemorningandeveningduringMaylト

Junel，2002at KC never reached the melting point．

Nosnowmeltingwasobservedthroughouttheobser−

Vation period，eVen during the day，althoughsnow
attached to plywood，tentS etC．SOmetimes melted

duringthemiddayduetothestrongsolarradiation．

Wedidpit−StudiesatKCandQS．AtKC，Wedug

Sixpitsandcollectedpit−Wallsamplesfromtwoofthe

pitsthatwerel．8and2．7mdeep．Thepit−Wallsamples
wi11be analyzed for stableisotopes，ion chemistry，trace metals，and microbiology．The rest ofthe pits
Werel−1．3m deep and used for density and snow

temperaturemeasurementsonly．ToinvestigateatQS

SingleOtterforourentireaircraftmission．However， the effects of snow melting on stableisotopes，ion
Chemistry andmicrobiology，We dug a pit and col−duetoacross−borderflyingproblemthataroseafter

Weflewouthalf oftheice cores and two persons toChitina，We COuld not use the Alaskan operator any
longertopulloutthecampandtoflyouttherestof

theicecoresandmembers．SowehadtouseCanadianaircraft operators to fly us to Kluane Lake，Yukon
TerritoryinsteadofChitina．WecharteredaBellJet
Ranger206helicopterfromTransNorthHelicoptersforflyingbetweenKCandQS，andaTwinOtterplanefrom AklakInc．for flying between QS and Kluane

1ected pit−Wallsamples before and during the major

melt−SeaSOn．

Figure3shows the visible stratigraphy of a2．7

m−deeppitdugat KConMay25−May26，2002．The

top O．585m of the pit consisted of new snow andCOmpaCted snow，Which werelikely deposited during

Winter2001／2002andspring2002．BetweenO．585andO．935m depths，We found a soft hoarlayer and soft
faceted−grainedlayers．This depth segmentlikelyLake．

COrreSpOnds to the snow depositioninlate summer／Cated ourlogistics substantially，allice cores safely
arrivedinJapan．TheicecoresflowntoChitinawere
ShippedtoAnchorage，Alaskabyafreezertruckandthen directly flown toJapan．The rest of the cores
flown to Kluane Lake were shipped to Vancouver，Canada viaWhitehorse，Yukon Territorybyfreezer
trucksandthensenttoJapanbyaboatequippedwith

found hard granular snowlayers，a relatively hard

Althoughthecross−borderflyingproblemcompli−

afreezercontainer．Whenwecheckedallofthecoresin a freezer facilityinJapan，We did not find any
evidence ofmeltingduringtransportation．
ユJ∴り（イ川ハ）／（梁■ん、（J／（両川・（J／／り〃＝川〔／川州・／）／／∫／／J（／ん〉ヾ

WemademeteorologicalobservationsfromMay

fal12001．Below this depth and down tol．09m，We
faceted−grainedlayer，and anicelayer2mm thick．
ThelayersbetweenO．935andl．09mareprobablythe
majorsummerlayersof2001．AlOmmthickicelayer，
locatedfurtherdownatl．21m，WaSlikelycausedby

refreezingofmeltwaterfromtheuppermajorsummer

layers．Adistinct，brownish，dirtlayerwasatl．54−1．

59m of the KC pit．Thislayerlikely contains dust
blown from the Gobi Desert by a dust storm andarrived on Mt．Loganinlate Apri12001（Zdanowicz，personalcommunication）．BelowtheGobidustlayer，
thestratigraphywasmainlyhard，Wind−paCkedsnow

that presumably depositedin winter2000／2001andearlyspring2001．
llthroughJunel，2002atKC．Weather，Cloudamount，This Gobidustlayer was also observedin May
Cloudtype，andvisibilitywererecorded．Airtempera−
turewasmeasuredwithathermister，andwindspeed
2001near the snow surface at KC．Therefore，SnOWAzuma et al．

（＃タTable2．ResultsofmeteorologicalobservationsatKingColin2002．
Airtemperature O Windspeed

Date＆time Weather Cloudamount Cloudtype5／1109：00

C

5／1121：00

S

10
10

5／1209：00

2

5／1221：00
5／1308：00

6

5／1320：00

10S

5／1408：00

8S10101010
105／1708：00

C

9

5／1720：00

g

5／1420：00

S

5／1508：15

S

5／1520：00

S

5／1608：00

cb

5／1620：00

5／1808：00
5／1820：00

5／1908：00

0

C

9fb

5／1920：00
5／2008：00
5／2020：10

（C）

Ac
Ac
AcIAsl
Ac
Ac
Ac
Ac
Ac
Ac
Ac
Ac
Ac
Ci

−20．3

5／2220：12

8
S

5／2320：00

3

5／2408：00
5／2419：50

3
C

9

−20．9
−15．2
−16．9

4

−19．1

5

−13．3
−12．8
−14．3

Ac
Ac
Ac
Ac
Ac

−14．6
−13．7
−11．2

−82

−13．7

2

−9．4
−11，6
−14．1
−13．1
−6．9

5／2808：00

S

5／2908：00

S

5／2920：00

S

10
105／3008：00

S

95／3021：00

45／3107：55
5／3121：00

6／108：10

8

CC：Cloudy
S：SnOWlng
f：fine（cloudamoutOp8）
b：blowingsnow
g：foggy

9AcAs
Ac As

−7．3
−5．2
−9．8

Ac

−12．6

54

2．5
3．8
2．1
1．3
0．9
2．8

−15．2

As
Ac
Ac
Ac
Ac
Ac：Altocumulus
Ci：Cirrus
As：Altostratus

−18．3
−16．8
−20．5

w14．1
−17．7

一tトWhd＄P00d（m／S）

76S

ESE
SW
NNE
NNE
NE
SE
ENE
ENE
SW
SSW
ENE
E

−11．48︵の︑∈︶
p￠
乳のPu
傭
き2

0．9
1，11．51．5
1．8
2．9
2．9

−8．5

−13．3

104

0．6

−9．1

0C

0．5

−11．7

Ac2Asl
Ac

NNE
SSW
NE
SE
SSW
SW
SSE
N
SW
WNW

0．7−7Ac

NE
W
ENE
NNW

0−10．25／2608：00

5／2720：14

0

4．9
6．7
7．1
2．7

−16．7

09E
ENE
ENE
ESE
ENE
SE

3．7
2．6

−18．6

0C

0−22．8

5／2520：00

5／2713：40

ENE
ESE
ESE
E

1．5

−16．7

5／2507：55

5／2620：00

0，8
2．2
2．6
4．1

−22．8

Ci

5／2308：10

0−22．15／2108：00
5／2208：00

（km）

E

−18．9

05／2120：00

Visibility

（m／s）

▲

−▲・・
Air temperature′▲●■こ・、▲ごリキ．い．

320︵0010 ︶空っ扇﹂
1巴5 ∈02こ苛50

1

0200釘5／9 2002／5／14 2002／5／19 2002／5／24 200釘5／29 2002／酎3Fig．2．WindspeedandairtemperatureatKingCol．

3

0．5
1050
50
0．5
50
3
5

0．5
5

0．5
50
0．5
50
50
50
50
50
50
50
50
50
0．150
50
50
50
50
50
50
50
0．5
100．05
50．3
50
50
0．5

BulletinofGlaciologicalResearch

7り＊ N8WSnOW● Compadodsnow
O Granularsnow

人 ughtlycompactedsnow
口 Facot8dcⅣぬ】s︵∈︶≦d①
凸・・−・・・Crust■llc01ayor△ Hoar− Dinlayerh HardS So允

Fig．3．VisiblestratigraphyofapitatKingCol．TheGPS
COOrdinatesofthepitwas60O35 20 N，140036 11A W．

Thevisiblestratigraphyofthepit，thelowsnow

accumulation between May2001and May2002wasaboutl．59m．AccordingtothedensityprofileinFig． temperaturesofthepit（Fig．4），andthelackofsurface
meltingduringthethreefieldseasons（July24−August4，thenetsnowaccumulationbetweenMay2001andMay2002wasaboutO．6mw．e．a▼1．Observationsinl，2000，May−June2001，andMay−June2002）confirms

May2001indicated that the net snow accumulationthat KC has verylittle summer melting．Verylittle

betweenspring2000andsprlng2001wasabout3．9m， melt effects areexpected onphysical，Chemical，and
whichsuggestsalargeyear−tO−yearVariationofsnow biologicalstratigraphyoftheKCcore．
accumulationrate at KC．

Density（kg／m3）
0500

1000 −20Temperature（Oc）
・100︵∈︶壬d￠
凸2

一●−Snow
tompor8tu「eFig．4．Density and temperature profiles of a pit at KingCol．

Azuma et al．

7ヱ

3．ProcessingandanalysesoftheKingColicecore
Weduga sciencetrench atKingColto processthecore．Inthetrench，WeuSedalight−tabletoobservethestratigraphyofthewhole220，52mcore．AIso，thetop30m ofthe core wascutinhalf alongthe coreaxis．Ahalfofthecore（crosssectionEinFig．5）wasthen（1）cutintoO．05−0．06mlongsegments，（2）melted
in either pre・Cleaned plastic bottles or WhirlPak

plastic bags after the sample surface was removed
with clean ceramic knives and disposable plastic

gloves，（3）decantedinto pre−Cleaned plastic bottles，and（4）refrozeninthesciencetrench．Samplesbottled
inthefieldwillbeanalyzedfor6180，6D，ionchemisT
try，andmicrobiology．

Fig．5．Corecuttingplan．

Planned analysesofthecross sectionregions ofsuch as detailed geochemical analyses of dust and
theKCcore（Fig．5）arelistedinTable3．Below30m， tephraparticles．

SeCtionDwillbearchivedforpotentialfuturestudies
Table3．PlannedanalysesoftheKingCoIcore．
Depth（m）
0−30

Cross−SeCtion
A
B＋C
B
C

D

30−70

Plannedanalyses
Tritium
Non−destructivedensitymeasurementwith
Ⅹ・rayS（Horietal．，1999）
Tracemetals
Verticalthin−SeCtionanalyses（crystalsizeetc．）

Insolubleparticles（sizeandnumber）

E

6180，6D，ions，SnOWalgae，bacteriaA

Tritium

B＋C

NonTdestructivedensitymeasurementwith
ⅩTrayS

BCD
E70−220．5AB

Tracemetals
Verticalthin−SeCtionanalyses（crystalsize

SamplingintervalContinuous，Samplelengthto
bedecided

Everyl−2m

Continuous，Samplelengthto
bedecided
Continuous，Samplelength0．05−0．06m
Continuous，Samplelengthto
bedecided

Everyト2metc．）

Archive
6180，6D，ions，insoluble particles，SnOW Continuous，Samplelength
algae，bacteria
0．05−0．06m
Tritium
Continuous，Samplelengthto
bedecided
Tracemetals
Everyl−2m

Horizontalthin−SeCtionanalyses（crystalSize，icefabricsetc．）

CDEDNA
Two samples in total
Verticalthin−SeCtionanalyses（crystalsize，icefabricsetc．）Archive
6180，6D，ions，insoluble particles，SnOW Continuous，Samplelengthto
algae，bacteria
bedecided

Z2

BulletinofGlaciologicalResearch

Acknowledgments

Goto−Azuma，K．，Koerner，R．M．andFisher，D．A．（2002）：Anice
COrereCOrdoverthelasttwocenturiesfromPennyIceCap，
BaffinIsland，Canada．Ann．Glaciol．，35，inpress．
We greatly appreciate ShuheiTakahashiand
Grumet，N．S．，Wake，C．PリMayewski，P．A．，Zielinsk
TakaoKameda（KitamiInstituteofTechnology），Who
Whitlow，S．Ⅰ．，Koerner，R．M．，Fisher，D．A．andWoollett，kindlyprovideduswiththeirdrillsystem．WethankJ．M．（2001）：Variabilityofsea−iceinBaffin Bayoverthe
lastmillennium．ClimaticChange，49，129145．
David Fisher，Roy Koerner，MichaelDemuth，Chris−Holdsworth，GリKrouse，H．R．andPeake，E．（1988）：Trace−aCidtian Zdanowicz（GeologicalSurvey of Canada）for
ioncontent ofsha1lowsnow andicecores from mountaintheirlogistic assistance，Which was essentialto ourSitesinwesternCanada．Ann．Glaciol．10，16．
field operation，and Cameron Wake（University of Holdsworth，G．，Krouse，H．R．and Nosal，M．（1992）：Ice core
New Hampshire）and Lonnie Thompson（Ohio State
ClimatesignalsfromMountLogan，Yukon，AD1700−1987．
In ClimateSinceA．D．1500，R．S．Bradley and P．D．JonesUniversity）for their helpinice core storage and（Eds．），Routledge，London，pp．483−504．
transportation．We also thank Okitsugu Watanabe
Hori，A．，Tayuki，Kリ Narita，H．，Hondoh，H．，Fujit（NationalInstitute of Polar Research）for his advice
Kameda，T．，Shoji，H．，Azuma，N．，Kamiyama，K．，Fujii
Onthefieldlogistics．Weexpressourgratitudetothe
Motoyama，H．andWatanabe，0．（1999）：Adetaileddensity
ArcticInstituteofNorthAmericaandParksCanada
profile of the Dome Fujiice core by X−ray tranSmission
method．Ann．Glaciolリ29，21ト214．
fortheirsupportonourfieldprogram．
Moore，G．W．K．，Holdsworth，G．andAIverson，K．（2001）：
Fieldworkin2002wassupportedbyGrant−in−AidExtra−trOpicalresponse to ENSO as expressedin anice
forScientificResearchonPriorityAreas（B）（Project
COrefromtheSaintEliasMountain Range．Geophys．Res．
No．11208202，Principalinvestigator：Kumiko GotoT
Lett．，28，34573460．
Azuma），fundedbytheMinistryofEducation，Culture，
0 Dwyer，）．and70thers．（2000）：Methanesulfonic acidin a

Svalbardice core as anindicator of ocean climate．Geo−Sports，Science and Technology．Transportation ofphys．Res．Lett．，27，1159−1162．
theicecorestoJapanwassupportedbyGrant−in−Aid
Shiraiwa，T．，Goto−Azuma，K．，Matoba，S．，Yamasaki
for Creative Scientific Research（Project No．
Segawa，T．，Kanamori，S．，Matsuoka，K．and Fujii，Y．
14GSO202；Principalinvestigator：Takeo Hondoh），（2003）：Icecore drilling at King Col，Mount Logan2002．
also funded by the Ministry of Education，Culture，Bull．Glaciol．Res．20，5763．
Watanabe，0．and70thers．（2001）：Studies on climatic andSports，ScienceandTechnology．

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